Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/08/15
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1248 PM CDT MON APR 6 2015
.AVIATION...
A WARM FRONT LIES ACROSS CENTRAL ARKANSAS THIS AFTERNOON. FOG HAS
BEEN SLOW TO DISSIPATE THROUGH THE DAY. CEILINGS SHOULD LIFT A BIT
THIS AFTERNOON. THE FRONT SHOULD LIFT NORTH OF THE STATE THIS
EVENING. SOME FOG AND LOW CLOUDS WILL RETURN TONIGHT AND AN UPPER
DISTURBANCE WILL BRING A CHANCE FOR SHOWERS FOR LATE TONIGHT INTO
EARLY TUESDAY MORNING. MAINLY VFR AND MVFR CONDITIONS ARE EXPECTED
THROUGH THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1015 AM CDT MON APR 6 2015/
DISCUSSION...
EARLY UPDATE LOWERED POP OVER CENTRAL TO WESTERN AR TO
SLIGHT...WHILE KEEPING A CHANCE OVER EASTERN TO SOUTHERN AR.
ATMOSPHERE REMAIN QUITE MOIST AND WITH LOW LEVEL MOISTURE
ELEVATED...FOG HAS HELD ON MOST OF THIS MORNING. 12Z KLZK SOUNDING
HAD A PRECIP WATER VALUE OF 1.37 INCHES...WITH AN ELEVATED SW FLOW
FROM GRADIENT LEVEL TO 10K FEET. MAIN MORNING CONVECTION HAS PUSHED
TO FAR NE AR AND OVER SE AR...WHILE NONE AT THIS TIME CENTRAL TO
WESTERN AREAS. DO SEE A SHORT WAVE IN THE MEAN UPPER FLOW OVER NE TX
TO SE AR...AND THIS WILL MOVE INTO AR LATE MORNING TO AFTERNOON.
SOME FORM OF A WARM FRONT IS SEEN OVER NORTHERN LA TO NE TX TO
CENTRAL OK. CURRENT FLOW SHOULD MOVE THIS NORTHWARD TODAY...BUT HOW
FAR STILL IS IN QUESTION. DO HAVE A BIT MORE POP EXPECTED THIS
AFTERNOON...BUT AT THIS TIME CAN ONLY GO 30-50% DUE TO A BIT OF
UNCERTAINTY. SHORT RANGE MODELS INDICATED SOME CONVECTION POTENTIAL
BUT MORE OF AN ISOLATED TREND. SOME INSTABILITY AND SURFACE BASED
CAPE IS SEEN ALONG WITH THE WEAK SHORT WAVE. WILL ADJUST FORECAST TO
SHOWERS WITH ISOLATED THUNDER. LATE MORNING WILL FINE TUNE
CONVECTION CHANCES AS WELL AS TEMPS. TEMPS WILL BE LOWERED A BIT DUE
TO FOG AND LOW CLOUDS HOLDING MUCH LONGER...ESPECIALLY IF THE WARM
FRONT DOES NOT LIFT MUCH NORTHWARD INTO AR. (59)
PREV DISCUSSION... /ISSUED 622 AM CDT MON APR 6 2015/
AVIATION...
OVER THE NEXT 24 HOURS...CONDITIONS WILL LARGELY VARY BETWEEN IFR
AND MVFR...WITH PATCHY FOG AND LIGHT RAIN OR DRIZZLE THIS MORNING.
CONDITIONS SHOULD GRADUALLY IMPROVE THIS AFTERNOON...WITH MAYBE A
BRIEF VFR PERIOD THIS EVENING. MVFR CONDITIONS WILL BECOME
PREVALENT BEFORE DAWN ON TUESDAY...AS MORE LOW LEVEL MOISTURE
MOVES INTO THE REGION.
PREV DISCUSSION... /ISSUED 427 AM CDT MON APR 6 2015/
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
HAVE ALREADY SEEN DEWPOINTS AROUND THE STATE INCREASE CLOSE TO 20
DEGREES IN THE PAST TWENTY FOUR HOURS. MOISTURE CONTINUED TO
INCREASE THROUGH THE OVERNIGHT HOURS WITH SOME SCATTERED SHOWERS AND
PATCHY FOG DEVELOPING. CONDITIONS WILL CONTINUE TO IMPROVE THROUGH
THE MORNING WITH SHOWERS AND PATCHY FOG DISSIPATING.
WARM FRONT WILL CONTINUE TO LIFT NORTH THROUGH THE STATE TODAY.
FRONT SHOULD BE THROUGH THE STATE BY 00Z. A GENERALLY CAPPED
ATMOSPHERE WILL BE IN PLACE AROUND THE STATE ON MONDAY...LIMITING
ANY THUNDERSTORM DEVELOPMENT. HOWEVER...NAM/ARW/NMM/HRRR MODEL
SOUNDINGS ACROSS SOUTHERN AND SOUTHEAST ARKANSAS DO SUGGEST THE CAP
WOULD ERODE ENOUGH TO ALLOW FOR THUNDERSTORM DEVELOPMENT...WITH THE
NAM BEING THE MOST AGGRESSIVE IN THIS SOLUTION. CONVERSELY...THE GFS
IS A BIT COOLER AND DRIER AT THE SURFACE AND SUGGESTS THE CAP WILL
HOLD TOUGH. CURRENT FORECAST HAS SURFACE TEMPS/DEWPOINTS A BIT
CLOSER TO THE NAM SOLUTION...THEREFORE WILL INCREASE POPS ACROSS THE
SOUTHERN PORTION OF THE STATE. 05Z HRRR ALSO BEGINS TO SUGGEST SOME
THUNDERSTORM DEVELOPMENT WILL OCCUR IN SOUTHERN ARKANSAS WITH THE
06Z CONTINUING THIS TREND. IF THUNDERSTORMS CAN DEVELOP IN SOUTHERN
ARKANSAS THEY WILL HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE
WITH LARGE HAIL THE MAIN THREAT. PORTIONS OF SW ARKANSAS WILL BE
MOST LIKELY TO SEE SE WINDS...INCREASING HELICITY. LCL HEIGHTS ARE A
BIT ON THE HIGH SIDE...BUT STILL LOW ENOUGH TO SUPPORT A TORNADO TO
FORM. STRONG TO SEVERE STORMS ARE EXPECTED TO BE QUITE ISOLATED IN
COVERAGE...AND THERE EXISTS QUITE A BIT OF UNCERTAINTY WITH THIS.
TUESDAY WILL ALSO SEE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS AROUND THE STATE WITH YET ANOTHER CAPPED ENVIRONMENT
IN PLACE. SURFACE WINDS WILL BE A BIT STRONGER ON TUESDAY...BUT AT
THIS POINT ARE JUST BELOW LAKE WIND ADVISORY THRESHOLD...BUT WILL
NEED TO BE MONITORED IN FUTURE FORECASTS.
WEDNESDAY...THE RIDGE OVER ARKANSAS WILL BEGIN TO WEAKEN...ALLOWING
TEMPERATURES TO COOL ALOFT RESULTING IN THE CAP BEGINNING TO WEAKEN.
SURFACE LOW PRESSURE AND ASSOCIATED COLD FRONT WILL STILL REMAIN
WELL TO THE WEST OF THE STATE...KEEPING BEST PRECIPITATION CHANCES
ACROSS WESTERN AND NORTHWESTERN ARKANSAS. A FEW STORMS COULD HAVE
THE POTENTIAL TO BECOME SEVERE...BUT THIS WOULD GENERALLY BE ACROSS
EXTREME WESTERN ARKANSAS.
LONG TERM...THURSDAY THROUGH SUNDAY
LITTLE CHANGE IN THE GOING FORECAST. WHILE THE SMALL DETAILS MAY
VARY A BIT...THE OVERALL PICTURE REMAINS THE SAME. AT THE BEGINNING
OF THE PERIOD...SHOWERS AND THUNDERSTORMS WILL BE LIKELY...AS A COLD
FRONT APPROACHES THE REGION FROM THE WEST.
WITH THE FRONT...SOME THUNDERSTORMS ON THURSDAY AND THURSDAY NIGHT
COULD BE SEVERE. AT THIS POINT...ALL MODES LOOK POSSIBLE...WITH THE
HIGHEST THREAT DURING THE AFTERNOON AND EVENING HOURS. THE EXTENT OF
THE THREAT WILL ALL DEPEND ON HOW MUCH THINGS DESTABILIZE OUT AHEAD
OF THE FRONT. ALSO...ANY STRONGER STORMS WOULD BE CAPABLE OF
PRODUCING HEAVY RAINFALL...GIVEN PRECIPITABLE WATER VALUES
APPROACHING TWO INCHES.
FRONT WILL PUSH SOUTHEAST OF THE REGION AROUND FRIDAY MORNING.
RETAINED SMALL RAIN CHANCES BEHIND THE FRONT...AS THE MODELS TEND TO
PUSH SYSTEMS OUT OF THE REGION A BIT FAST THIS TIME OF YEAR. THE
FRONT WILL STALL OUT TO THE SOUTH OF THE REGION...BEFORE BACKING TO
THE NORTH AS A WARM FRONT AROUND SUNDAY...WITH THE CHANCE OF SHOWERS
AND THUNDERSTORMS INCREASING. IT IS LOOKING LIKE STRONG
THUNDERSTORMS COULD BE A POSSIBILITY WITH THIS SYSTEM AS WELL...AND
FORECAST TRENDS WILL CONTINUE TO BE MONITORED.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 62 78 64 81 / 20 20 20 20
CAMDEN AR 63 80 65 82 / 20 10 10 10
HARRISON AR 60 78 62 78 / 20 10 30 30
HOT SPRINGS AR 63 79 65 80 / 20 10 10 20
LITTLE ROCK AR 63 80 65 81 / 20 10 10 20
MONTICELLO AR 65 82 66 83 / 20 20 10 10
MOUNT IDA AR 64 78 65 79 / 20 10 10 20
MOUNTAIN HOME AR 60 80 62 82 / 20 20 30 30
NEWPORT AR 64 79 64 81 / 20 20 20 20
PINE BLUFF AR 64 80 64 83 / 20 10 10 20
RUSSELLVILLE AR 61 79 63 81 / 20 10 20 20
SEARCY AR 61 79 61 81 / 20 20 10 20
STUTTGART AR 63 81 64 82 / 20 20 10 20
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...51
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
1015 AM CDT MON APR 6 2015
.DISCUSSION...
EARLY UPDATE LOWERED POP OVER CENTRAL TO WESTERN AR TO
SLIGHT...WHILE KEEPING A CHANCE OVER EASTERN TO SOUTHERN AR.
ATMOSPHERE REMAIN QUITE MOIST AND WITH LOW LEVEL MOISTURE
ELEVATED...FOG HAS HELD ON MOST OF THIS MORNING. 12Z KLZK SOUNDING
HAD A PRECIP WATER VALUE OF 1.37 INCHES...WITH AN ELEVATED SW FLOW
FROM GRADIENT LEVEL TO 10K FEET. MAIN MORNING CONVECTION HAS PUSHED
TO FAR NE AR AND OVER SE AR...WHILE NONE AT THIS TIME CENTRAL TO
WESTERN AREAS. DO SEE A SHORT WAVE IN THE MEAN UPPER FLOW OVER NE TX
TO SE AR...AND THIS WILL MOVE INTO AR LATE MORNING TO AFTERNOON.
SOME FORM OF A WARM FRONT IS SEEN OVER NORTHERN LA TO NE TX TO
CENTRAL OK. CURRENT FLOW SHOULD MOVE THIS NORTHWARD TODAY...BUT HOW
FAR STILL IS IN QUESTION. DO HAVE A BIT MORE POP EXPECTED THIS
AFTERNOON...BUT AT THIS TIME CAN ONLY GO 30-50% DUE TO A BIT OF
UNCERTAINTY. SHORT RANGE MODELS INDICATED SOME CONVECTION POTENTIAL
BUT MORE OF AN ISOLATED TREND. SOME INSTABILITY AND SURFACE BASED
CAPE IS SEEN ALONG WITH THE WEAK SHORT WAVE. WILL ADJUST FORECAST TO
SHOWERS WITH ISOLATED THUNDER. LATE MORNING WILL FINE TUNE
CONVECTION CHANCES AS WELL AS TEMPS. TEMPS WILL BE LOWERED A BIT DUE
TO FOG AND LOW CLOUDS HOLDING MUCH LONGER...ESPECIALLY IF THE WARM
FRONT DOES NOT LIFT MUCH NORTHWARD INTO AR. (59)
&&
.PREV DISCUSSION... /ISSUED 622 AM CDT MON APR 6 2015/
.AVIATION...
OVER THE NEXT 24 HOURS...CONDITIONS WILL LARGELY VARY BETWEEN IFR
AND MVFR...WITH PATCHY FOG AND LIGHT RAIN OR DRIZZLE THIS MORNING.
CONDITIONS SHOULD GRADUALLY IMPROVE THIS AFTERNOON...WITH MAYBE A
BRIEF VFR PERIOD THIS EVENING. MVFR CONDITIONS WILL BECOME
PREVALENT BEFORE DAWN ON TUESDAY...AS MORE LOW LEVEL MOISTURE
MOVES INTO THE REGION.
&&
.PREV DISCUSSION... /ISSUED 427 AM CDT MON APR 6 2015/
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
HAVE ALREADY SEEN DEWPOINTS AROUND THE STATE INCREASE CLOSE TO 20
DEGREES IN THE PAST TWENTY FOUR HOURS. MOISTURE CONTINUED TO
INCREASE THROUGH THE OVERNIGHT HOURS WITH SOME SCATTERED SHOWERS AND
PATCHY FOG DEVELOPING. CONDITIONS WILL CONTINUE TO IMPROVE THROUGH
THE MORNING WITH SHOWERS AND PATCHY FOG DISSIPATING.
WARM FRONT WILL CONTINUE TO LIFT NORTH THROUGH THE STATE TODAY.
FRONT SHOULD BE THROUGH THE STATE BY 00Z. A GENERALLY CAPPED
ATMOSPHERE WILL BE IN PLACE AROUND THE STATE ON MONDAY...LIMITING
ANY THUNDERSTORM DEVELOPMENT. HOWEVER...NAM/ARW/NMM/HRRR MODEL
SOUNDINGS ACROSS SOUTHERN AND SOUTHEAST ARKANSAS DO SUGGEST THE CAP
WOULD ERODE ENOUGH TO ALLOW FOR THUNDERSTORM DEVELOPMENT...WITH THE
NAM BEING THE MOST AGGRESSIVE IN THIS SOLUTION. CONVERSELY...THE GFS
IS A BIT COOLER AND DRIER AT THE SURFACE AND SUGGESTS THE CAP WILL
HOLD TOUGH. CURRENT FORECAST HAS SURFACE TEMPS/DEWPOINTS A BIT
CLOSER TO THE NAM SOLUTION...THEREFORE WILL INCREASE POPS ACROSS THE
SOUTHERN PORTION OF THE STATE. 05Z HRRR ALSO BEGINS TO SUGGEST SOME
THUNDERSTORM DEVELOPMENT WILL OCCUR IN SOUTHERN ARKANSAS WITH THE
06Z CONTINUING THIS TREND. IF THUNDERSTORMS CAN DEVELOP IN SOUTHERN
ARKANSAS THEY WILL HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE
WITH LARGE HAIL THE MAIN THREAT. PORTIONS OF SW ARKANSAS WILL BE
MOST LIKELY TO SEE SE WINDS...INCREASING HELICITY. LCL HEIGHTS ARE A
BIT ON THE HIGH SIDE...BUT STILL LOW ENOUGH TO SUPPORT A TORNADO TO
FORM. STRONG TO SEVERE STORMS ARE EXPECTED TO BE QUITE ISOLATED IN
COVERAGE...AND THERE EXISTS QUITE A BIT OF UNCERTAINTY WITH THIS.
TUESDAY WILL ALSO SEE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS AROUND THE STATE WITH YET ANOTHER CAPPED ENVIRONMENT
IN PLACE. SURFACE WINDS WILL BE A BIT STRONGER ON TUESDAY...BUT AT
THIS POINT ARE JUST BELOW LAKE WIND ADVISORY THRESHOLD...BUT WILL
NEED TO BE MONITORED IN FUTURE FORECASTS.
WEDNESDAY...THE RIDGE OVER ARKANSAS WILL BEGIN TO WEAKEN...ALLOWING
TEMPERATURES TO COOL ALOFT RESULTING IN THE CAP BEGINNING TO WEAKEN.
SURFACE LOW PRESSURE AND ASSOCIATED COLD FRONT WILL STILL REMAIN
WELL TO THE WEST OF THE STATE...KEEPING BEST PRECIPITATION CHANCES
ACROSS WESTERN AND NORTHWESTERN ARKANSAS. A FEW STORMS COULD HAVE
THE POTENTIAL TO BECOME SEVERE...BUT THIS WOULD GENERALLY BE ACROSS
EXTREME WESTERN ARKANSAS.
LONG TERM...THURSDAY THROUGH SUNDAY
LITTLE CHANGE IN THE GOING FORECAST. WHILE THE SMALL DETAILS MAY
VARY A BIT...THE OVERALL PICTURE REMAINS THE SAME. AT THE BEGINNING
OF THE PERIOD...SHOWERS AND THUNDERSTORMS WILL BE LIKELY...AS A COLD
FRONT APPROACHES THE REGION FROM THE WEST.
WITH THE FRONT...SOME THUNDERSTORMS ON THURSDAY AND THURSDAY NIGHT
COULD BE SEVERE. AT THIS POINT...ALL MODES LOOK POSSIBLE...WITH THE
HIGHEST THREAT DURING THE AFTERNOON AND EVENING HOURS. THE EXTENT OF
THE THREAT WILL ALL DEPEND ON HOW MUCH THINGS DESTABILIZE OUT AHEAD
OF THE FRONT. ALSO...ANY STRONGER STORMS WOULD BE CAPABLE OF
PRODUCING HEAVY RAINFALL...GIVEN PRECIPITABLE WATER VALUES
APPROACHING TWO INCHES.
FRONT WILL PUSH SOUTHEAST OF THE REGION AROUND FRIDAY MORNING.
RETAINED SMALL RAIN CHANCES BEHIND THE FRONT...AS THE MODELS TEND TO
PUSH SYSTEMS OUT OF THE REGION A BIT FAST THIS TIME OF YEAR. THE
FRONT WILL STALL OUT TO THE SOUTH OF THE REGION...BEFORE BACKING TO
THE NORTH AS A WARM FRONT AROUND SUNDAY...WITH THE CHANCE OF SHOWERS
AND THUNDERSTORMS INCREASING. IT IS LOOKING LIKE STRONG
THUNDERSTORMS COULD BE A POSSIBILITY WITH THIS SYSTEM AS WELL...AND
FORECAST TRENDS WILL CONTINUE TO BE MONITORED.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...57
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
622 AM CDT MON APR 6 2015
.AVIATION...
OVER THE NEXT 24 HOURS...CONDITIONS WILL LARGELY VARY BETWEEN IFR
AND MVFR...WITH PATCHY FOG AND LIGHT RAIN OR DRIZZLE THIS MORNING.
CONDITIONS SHOULD GRADUALLY IMPROVE THIS AFTERNOON...WITH MAYBE A
BRIEF VFR PERIOD THIS EVENING. MVFR CONDITIONS WILL BECOME
PREVALENT BEFORE DAWN ON TUESDAY...AS MORE LOW LEVEL MOISTURE
MOVES INTO THE REGION.
&&
.PREV DISCUSSION... /ISSUED 427 AM CDT MON APR 6 2015/
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
HAVE ALREADY SEEN DEWPOINTS AROUND THE STATE INCREASE CLOSE TO 20
DEGREES IN THE PAST TWENTY FOUR HOURS. MOISTURE CONTINUED TO
INCREASE THROUGH THE OVERNIGHT HOURS WITH SOME SCATTERED SHOWERS AND
PATCHY FOG DEVELOPING. CONDITIONS WILL CONTINUE TO IMPROVE THROUGH
THE MORNING WITH SHOWERS AND PATCHY FOG DISSIPATING.
WARM FRONT WILL CONTINUE TO LIFT NORTH THROUGH THE STATE TODAY.
FRONT SHOULD BE THROUGH THE STATE BY 00Z. A GENERALLY CAPPED
ATMOSPHERE WILL BE IN PLACE AROUND THE STATE ON MONDAY...LIMITING
ANY THUNDERSTORM DEVELOPMENT. HOWEVER...NAM/ARW/NMM/HRRR MODEL
SOUNDINGS ACROSS SOUTHERN AND SOUTHEAST ARKANSAS DO SUGGEST THE CAP
WOULD ERODE ENOUGH TO ALLOW FOR THUNDERSTORM DEVELOPMENT...WITH
THE NAM BEING THE MOST AGGRESSIVE IN THIS SOLUTION. CONVERSELY...THE GFS
IS A BIT COOLER AND DRIER AT THE SURFACE AND SUGGESTS THE CAP WILL
HOLD TOUGH. CURRENT FORECAST HAS SURFACE TEMPS/DEWPOINTS A BIT
CLOSER TO THE NAM SOLUTION...THEREFORE WILL INCREASE POPS ACROSS THE
SOUTHERN PORTION OF THE STATE. 05Z HRRR ALSO BEGINS TO SUGGEST
SOME THUNDERSTORM DEVELOPMENT WILL OCCUR IN SOUTHERN ARKANSAS WITH
THE 06Z CONTINUING THIS TREND. IF THUNDERSTORMS CAN DEVELOP IN
SOUTHERN ARKANSAS THEY WILL HAVE THE POTENTIAL TO BECOME STRONG TO
SEVERE WITH LARGE HAIL THE MAIN THREAT. PORTIONS OF SW ARKANSAS
WILL BE MOST LIKELY TO SEE SE WINDS...INCREASING HELICITY. LCL
HEIGHTS ARE A BIT ON THE HIGH SIDE...BUT STILL LOW ENOUGH TO
SUPPORT A TORNADO TO FORM. STRONG TO SEVERE STORMS ARE EXPECTED TO
BE QUITE ISOLATED IN COVERAGE...AND THERE EXISTS QUITE A BIT OF
UNCERTAINTY WITH THIS.
TUESDAY WILL ALSO SEE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS AROUND THE STATE WITH YET ANOTHER CAPPED ENVIRONMENT
IN PLACE. SURFACE WINDS WILL BE A BIT STRONGER ON TUESDAY...BUT AT
THIS POINT ARE JUST BELOW LAKE WIND ADVISORY THRESHOLD...BUT WILL
NEED TO BE MONITORED IN FUTURE FORECASTS.
WEDNESDAY...THE RIDGE OVER ARKANSAS WILL BEGIN TO WEAKEN...ALLOWING
TEMPERATURES TO COOL ALOFT RESULTING IN THE CAP BEGINNING TO WEAKEN.
SURFACE LOW PRESSURE AND ASSOCIATED COLD FRONT WILL STILL REMAIN
WELL TO THE WEST OF THE STATE...KEEPING BEST PRECIPITATION CHANCES
ACROSS WESTERN AND NORTHWESTERN ARKANSAS. A FEW STORMS COULD HAVE
THE POTENTIAL TO BECOME SEVERE...BUT THIS WOULD GENERALLY BE ACROSS
EXTREME WESTERN ARKANSAS.
LONG TERM...THURSDAY THROUGH SUNDAY
LITTLE CHANGE IN THE GOING FORECAST. WHILE THE SMALL DETAILS MAY
VARY A BIT...THE OVERALL PICTURE REMAINS THE SAME. AT THE BEGINNING
OF THE PERIOD...SHOWERS AND THUNDERSTORMS WILL BE LIKELY...AS A COLD
FRONT APPROACHES THE REGION FROM THE WEST.
WITH THE FRONT...SOME THUNDERSTORMS ON THURSDAY AND THURSDAY NIGHT
COULD BE SEVERE. AT THIS POINT...ALL MODES LOOK POSSIBLE...WITH THE
HIGHEST THREAT DURING THE AFTERNOON AND EVENING HOURS. THE EXTENT OF
THE THREAT WILL ALL DEPEND ON HOW MUCH THINGS DESTABILIZE OUT AHEAD
OF THE FRONT. ALSO...ANY STRONGER STORMS WOULD BE CAPABLE OF
PRODUCING HEAVY RAINFALL...GIVEN PRECIPITABLE WATER VALUES
APPROACHING TWO INCHES.
FRONT WILL PUSH SOUTHEAST OF THE REGION AROUND FRIDAY MORNING.
RETAINED SMALL RAIN CHANCES BEHIND THE FRONT...AS THE MODELS TEND TO
PUSH SYSTEMS OUT OF THE REGION A BIT FAST THIS TIME OF YEAR. THE
FRONT WILL STALL OUT TO THE SOUTH OF THE REGION...BEFORE BACKING TO
THE NORTH AS A WARM FRONT AROUND SUNDAY...WITH THE CHANCE OF SHOWERS
AND THUNDERSTORMS INCREASING. IT IS LOOKING LIKE STRONG
THUNDERSTORMS COULD BE A POSSIBILITY WITH THIS SYSTEM AS WELL...AND
FORECAST TRENDS WILL CONTINUE TO BE MONITORED.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...57
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
427 AM CDT MON APR 6 2015
.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
HAVE ALREADY SEEN DEWPOINTS AROUND THE STATE INCREASE CLOSE TO 20
DEGREES IN THE PAST TWENTY FOUR HOURS. MOISTURE CONTINUED TO
INCREASE THROUGH THE OVERNIGHT HOURS WITH SOME SCATTERED SHOWERS AND
PATCHY FOG DEVELOPING. CONDITIONS WILL CONTINUE TO IMPROVE THROUGH
THE MORNING WITH SHOWERS AND PATCHY FOG DISSIPATING.
WARM FRONT WILL CONTINUE TO LIFT NORTH THROUGH THE STATE TODAY.
FRONT SHOULD BE THROUGH THE STATE BY 00Z. A GENERALLY CAPPED
ATMOSPHERE WILL BE IN PLACE AROUND THE STATE ON MONDAY...LIMITING
ANY THUNDERSTORM DEVELOPMENT. HOWEVER...NAM/ARW/NMM/HRRR MODEL
SOUNDINGS ACROSS SOUTHERN AND SOUTHEAST ARKANSAS DO SUGGEST THE CAP
WOULD ERODE ENOUGH TO ALLOW FOR THUNDERSTORM DEVELOPMENT...WITH
THE NAM BEING THE MOST AGGRESSIVE IN THIS SOLUTION. CONVERSELY...THE GFS
IS A BIT COOLER AND DRIER AT THE SURFACE AND SUGGESTS THE CAP WILL
HOLD TOUGH. CURRENT FORECAST HAS SURFACE TEMPS/DEWPOINTS A BIT
CLOSER TO THE NAM SOLUTION...THEREFORE WILL INCREASE POPS ACROSS THE
SOUTHERN PORTION OF THE STATE. 05Z HRRR ALSO BEGINS TO SUGGEST
SOME THUNDERSTORM DEVELOPMENT WILL OCCUR IN SOUTHERN ARKANSAS WITH
THE 06Z CONTINUING THIS TREND. IF THUNDERSTORMS CAN DEVELOP IN
SOUTHERN ARKANSAS THEY WILL HAVE THE POTENTIAL TO BECOME STRONG TO
SEVERE WITH LARGE HAIL THE MAIN THREAT. PORTIONS OF SW ARKANSAS
WILL BE MOST LIKELY TO SEE SE WINDS...INCREASING HELICITY. LCL
HEIGHTS ARE A BIT ON THE HIGH SIDE...BUT STILL LOW ENOUGH TO
SUPPORT A TORNADO TO FORM. STRONG TO SEVERE STORMS ARE EXPECTED TO
BE QUITE ISOLATED IN COVERAGE...AND THERE EXISTS QUITE A BIT OF
UNCERTAINTY WITH THIS.
TUESDAY WILL ALSO SEE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS AROUND THE STATE WITH YET ANOTHER CAPPED ENVIRONMENT
IN PLACE. SURFACE WINDS WILL BE A BIT STRONGER ON TUESDAY...BUT AT
THIS POINT ARE JUST BELOW LAKE WIND ADVISORY THRESHOLD...BUT WILL
NEED TO BE MONITORED IN FUTURE FORECASTS.
WEDNESDAY...THE RIDGE OVER ARKANSAS WILL BEGIN TO WEAKEN...ALLOWING
TEMPERATURES TO COOL ALOFT RESULTING IN THE CAP BEGINNING TO WEAKEN.
SURFACE LOW PRESSURE AND ASSOCIATED COLD FRONT WILL STILL REMAIN
WELL TO THE WEST OF THE STATE...KEEPING BEST PRECIPITATION CHANCES
ACROSS WESTERN AND NORTHWESTERN ARKANSAS. A FEW STORMS COULD HAVE
THE POTENTIAL TO BECOME SEVERE...BUT THIS WOULD GENERALLY BE ACROSS
EXTREME WESTERN ARKANSAS.
&&
.LONG TERM...THURSDAY THROUGH SUNDAY
LITTLE CHANGE IN THE GOING FORECAST. WHILE THE SMALL DETAILS MAY
VARY A BIT...THE OVERALL PICTURE REMAINS THE SAME. AT THE BEGINNING
OF THE PERIOD...SHOWERS AND THUNDERSTORMS WILL BE LIKELY...AS A COLD
FRONT APPROACHES THE REGION FROM THE WEST.
WITH THE FRONT...SOME THUNDERSTORMS ON THURSDAY AND THURSDAY NIGHT
COULD BE SEVERE. AT THIS POINT...ALL MODES LOOK POSSIBLE...WITH THE
HIGHEST THREAT DURING THE AFTERNOON AND EVENING HOURS. THE EXTENT OF
THE THREAT WILL ALL DEPEND ON HOW MUCH THINGS DESTABILIZE OUT AHEAD
OF THE FRONT. ALSO...ANY STRONGER STORMS WOULD BE CAPABLE OF
PRODUCING HEAVY RAINFALL...GIVEN PRECIPITABLE WATER VALUES
APPROACHING TWO INCHES.
FRONT WILL PUSH SOUTHEAST OF THE REGION AROUND FRIDAY MORNING.
RETAINED SMALL RAIN CHANCES BEHIND THE FRONT...AS THE MODELS TEND TO
PUSH SYSTEMS OUT OF THE REGION A BIT FAST THIS TIME OF YEAR. THE
FRONT WILL STALL OUT TO THE SOUTH OF THE REGION...BEFORE BACKING TO
THE NORTH AS A WARM FRONT AROUND SUNDAY...WITH THE CHANCE OF SHOWERS
AND THUNDERSTORMS INCREASING. IT IS LOOKING LIKE STRONG
THUNDERSTORMS COULD BE A POSSIBILITY WITH THIS SYSTEM AS WELL...AND
FORECAST TRENDS WILL CONTINUE TO BE MONITORED.
&&
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 69 62 78 64 / 30 20 20 20
CAMDEN AR 78 63 80 65 / 40 10 10 10
HARRISON AR 72 60 78 62 / 20 20 10 30
HOT SPRINGS AR 75 63 79 65 / 30 10 10 10
LITTLE ROCK AR 74 63 80 65 / 30 20 10 10
MONTICELLO AR 76 65 82 66 / 40 20 20 10
MOUNT IDA AR 75 64 78 65 / 20 10 10 10
MOUNTAIN HOME AR 69 60 80 62 / 20 20 20 30
NEWPORT AR 69 64 79 64 / 30 20 20 20
PINE BLUFF AR 77 64 80 64 / 40 20 10 10
RUSSELLVILLE AR 73 61 79 63 / 30 10 10 20
SEARCY AR 72 61 79 61 / 30 20 20 10
STUTTGART AR 74 63 81 64 / 30 20 20 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...65 / LONG TERM...57
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
1231 AM CDT MON APR 6 2015
.AVIATION...
CONDITIONS WILL VARY BETWEEN MVFR AND IFR THIS MORNING...AS AN
UPPER SYSTEM MOVES AWAY FROM THE REGION. LIGHT RAIN OR DRIZZLE
WILL BE POSSIBLE EARLY. SOUTHERLY WINDS WILL INCREASE LATER THIS
MORNING...WITH CONDITIONS IMPROVING BY THE AFTERNOON HOURS. ALL
AREAS SHOULD BE VFR BY 00Z. TAFS ALREADY OUT.
&&
.PREV DISCUSSION... /ISSUED 919 PM CDT SUN APR 5 2015/
UPDATE...
UPPER LEVEL WAVE CONTINUES TO EXIT THE REGION TAKING THE BULK OF
THE PRECIPITATION WITH IT. ATTENTION WILL THEN TURN TO A WARM
FRONT EXPECTED TO ENTER THE STATE FROM THE SOUTHWEST DURING THE
OVERNIGHT HOURS. HAVE LOWERED POPS FOR THE OVERNIGHT HOURS BUT
STILL EXPECTING A FEW SHOWERS TO CONTINUE THROUGH THE NIGHT BASED
ON THE HRRR OUTPUT.
TEMPERATURES ALREADY CLOSE TO FORECASTED LOWS IN SOME AREAS AND
ADJUSTED ACCORDINGLY. DO NOT BELIEVE THERE WILL BE MUCH OF A DROP
OFF TONIGHT AS SOUTHERLY WINDS AND CLOUD COVER CONTINUE.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...57
AREA FORECAST DISCUSSION
NWS PUEBLO CO
325 PM MDT MON APR 6 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 245 PM MDT MON APR 6 2015
...SHORT TERM CONCERN REMAINS CRITICAL FIRE WEATHER CONDITIONS...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING A DEEP
SOUTHWESTERLY FLOW PATTERN ACROSS THE REGION WITH AN UPPER LOW AND
BROAD TROUGH JUST OFFSHORE THE PAC NORTHWEST COAST THROUGH THE WEST
COAST AND GREAT BASIN REGION. WATER VAPOR IMAGERY ALSO INDICATING AN
EMBEDDED SHORT WAVE TRANSLATING ACROSS THE GREAT BASIN AT THIS TIME.
LATEST SFC OBSERVATIONS INDICATING A WELL MIXED ATMOSPHERE ACROSS
THE AREA WITH BREEZY TO WINDY SOUTHWEST WINDS...WARM TEMPERATURES IN
THE 70S TO LOWER 80S LOWER ELEVATIONS...50S AND 60S ACROSS THE
HIGHER TERRAIN...DEW PTS MAINLY IN THE SINGLE DIGITS ABOVE AND BELOW
ZERO...ALL LEADING TO DANGEROUS FIRE WEATHER CONDITIONS BEING
EXPERIENCED ACROSS ALL OF THE NON SNOW COVERED AREAS OF SOUTH CENTRAL
AND SOUTHEAST COLORADO.
HOWEVER...LOW LEVEL MOISTURE IS NOT TOO FAR AWAY WITH REGIONAL
RADARS INDICATING A FINE LINE FROM NEAR DIA TO BURLINGTON AND INTO
WEST CENTRAL KANSAS...WITH DEW PTS IN THE 20S...30S AND 40S NORTH
AND EAST OF THE BOUNDARY INTO NORTHEASTERN COLORADO AND NORTHWESTERN
KANSAS.
TONIGHT AND TOMORROW...MODERATE TO STRONG SW FLOW ALOFT PROGGED TO
CONTINUE ACROSS THE AREA THROUGH THE PERIOD WITH GREAT BASIN
EMBEDDED WAVE CONTINUING TO TRANSLATE NORTH AND EAST ACROSS THE
NORTHERN ROCKIES TONIGHT AND ANOTHER SHORT WAVE PROGGED TO MOVE INTO
THE GREAT BASIN REGION THROUGH THE DAY TOMORROW. FIRST WAVE LOOKS TO
HELP PUSH LOW LEVEL MOISTURE GRADIENT/FRONT SOUTH AND WEST ACROSS
PORTIONS OF THE PALMER DVD AND NORTHERN PORTIONS OF THE SE PLAINS
TONIGHT WITH THE HRRR THE MOST AGGRESSIVE PUSHING MID 40 DEW PTS AND
STRATUS WELL INTO KIOWA AND PROWERS COUNTIES OVERNIGHT...WHICH MAY
BE A TAD OVERDONE. FURTHER WEST...WILL LIKELY SEE POOR RH RECOVERY
WITH LOWS SIMILAR TO LAST NIGHTS.
THIS BOUNDARY LOOKS TO MIX OUT THROUGH THE LATE MORNING AND EARLY
AFTERNOON TOMORROW AS LEE TROUGH STRENGTHENS ACROSS THE EASTERN
PLAINS AHEAD OF THE NEXT EMBEDDED SHORT WAVE. THIS ALL POINTS TO
ANOTHER DAY OF HIGH FIRE DANGER...ESPECIALLY FOR AREAS ALONG THE I-
25 CORRIDOR AND BACK WEST ACROSS THE REST OF THE EASTERN MTS TO THE
CONTDVD. WITH THAT SAID...HAVE UPGRADED AND EXPANDED A RED FLAG
WARNING FOR TOMORROW FROM NOON TO 8 PM FOR ALL OF THE NON SNOW
COVERED MTS...THE HIGH MT VALLEY AND THROUGH THE I-25 CORRIDOR. I
DID NOT INCLUDE THE FAR SE PLAINS WITH MARGINAL WINDS...THOUGH IF
DEEP ENOUGH MIXING CAN OCCUR...COULD SEE RED FLAG CONDITIONS THERE
AS WELL.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 245 PM MDT MON APR 6 2015
...DRY AND WINDY WEATHER CONTINUES...
A SERIES OF PROGRESSIVE TROUGHS WILL IMPACT OUR AREA OVER THE NEXT
SIX TO TEN DAYS...UNFORTUNATELY NONE OF THEM LOOK VERY ORGANIZED AND
IT LOOKS LIKE THERE WILL BE MORE WIND THAN PRECIPITATION FROM THIS
PATTERN. THE ONLY OPTIMISTIC THING THAT CAN BE SAID IS THAT THE
MODELS ARE STRUGGLING WITH THE PATTERN...SO THERE IS TIME FOR IT TO
CHANGE.
WEDNESDAY STILL LOOKS LIKE A DAY OF POTENTIALLY EXTREME FIRE
WEATHER. WITH INCREASING WRLY FLOW ALOFT...WILL SEE VERY LOW RH OVER
MOST OF THE AREA...AND ANOTHER ROUND OF STRONG-GUSTY WINDS IN THE
AFTERNOON AND EARLY EVE. HAVE HOISTED A FIRE WX WATCH FOR MOST OF
THE CWA. ONLY AREAS THAT MIGHT ESCAPE ARE THE PIKES PEAK REGION AND
THE CENTRAL MTS. TEMPS ALOFT WILL BE FALLING...SO DEPENDING ON THE
SPEED OF THE COLD FRONT THE RH VALUES FOR THE NRN AND CENTRAL MTN
AREAS MAY BE HIGH ENOUGH TO PRECLUDE RED FLAG. BUT IT WILL BE
ANOTHER DAY OF HIGH FIRE DANGER FOR THE PLAINS. EXTREME NERN
CORNER...BASICALLY KIOWA COUNTY...WILL BE A BIT SLOWER TO MIX OUT
DUE TO SOME MORNING LOW CLOUDS...BUT BY MID TO LATE AFTERNOON MOST
OF THE PLAINS SHOULD BE ON THE BREEZY-WINDY SIDE.
MODELS ARE NOW ALL ON BOARD WITH A MORE NORTHERLY TRACK FOR THE LATE
WED-THU SYSTEM. AS EXPECTED...THE OUTLIER ECMWF HAS FALLEN INTO LINE
WITH THE GFS...AND THE NAM-GFS SOLUTION HAS COME TOGETHER WITH A LOW
THAT TRACKS THROUGH WY. SO...PRECIP CHANCES NOT LOOKING VERY GOOD
FOR US RIGHT NOW. STILL LOOKS LIKE THE PIKES PEAK REGION AND CENTRAL
MTS N OF HGWY 50 WILL GET SOME SNOW...PERHAPS A COUPLE INCHES. BUT
ELSEWHERE...HAVE TRIMMED BACK THE LOW POPS AND WILL KEEP THEM SILENT
FOR NOW. TEMPS OVER THE PLAINS ON THU SHOULD BE MAINLY IN THE UPPER
50S-LOWER 60S.
RIDGING ON FRIDAY SHOULD MITIGATE FIRE WX CONCERNS...AS WINDS DIE
DOWN FOR A DAY OR SO. BUT IT STILL LOOKS DRY...AS DOES SATURDAY WHEN
SWRLY FLOW PICKS UP ONCE AGAIN AND LEADS TO MORE FIRE WX CONCERNS.
NEXT SYSTEM IS STILL BEING HANDLED QUITE DIFFERENTLY BY THE GLOBAL
MODELS. MODELS ARE ALL SHOWING A SPLIT SYSTEM...BUT THE GFS HAS A
WEAKER CUTOFF...AND BROAD DISORGANIZED CUTOFF LOW OVER NRN CO AND WY
BY MONDAY. THE ECMWF HAS A MORE ZONAL PATTERN TO OUR NORTH...BUT
KEEPS THE SRN CUTOFF SYSTEM TOO FAR SOUTH TO IMPACT OUR AREA.
NEITHER 12Z SOLUTION WOULD BRING US MUCH PRECIPITATION...WE JUST CAN
NOT GET A BREAK FROM THIS DISORGANIZED PATTERN! STILL...IT LOOKS
LIKE A CONTINUED PERIOD OF UNSETTLED WEATHER WITH SHOWERS PROBABLE
FOR AT LEAST THE MTN AREAS. ROSE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 245 PM MDT MON APR 6 2015
VFR CONDITIONS TO PREVAIL AT COS...PUB AND ALS OVER THE NEXT 24
HOURS. GUSTY SOUTHWEST WINDS 15-30KT EXPECTED THROUGH AT LEAST 02Z
TUE WITH SFC WINDS DIMINISHING THEREAFTER WITH LOSS OF SUN AND
MIXING. ALS TO SEE GUSTY SW WINDS AGAIN AFT 16Z TUE WITH A WEAK
FRONTAL BOUNDARY SLIDING ACROSS PORTIONS OF THE SE PLAINS POSSIBLY
DELAYING THE DEVELOPMENT OF GUSTY SW WINDS AT COS AND PUB UNTIL
18Z-21Z TUE.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ220>237.
FIRE WEATHER WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY
EVENING FOR COZ222-224>237.
RED FLAG WARNING FROM NOON TO 8 PM MDT TUESDAY FOR COZ220>230-
233.
&&
$$
SHORT TERM...MW
LONG TERM...ROSE
AVIATION...MW
AREA FORECAST DISCUSSION
NWS ALBANY NY
122 PM EDT MON APR 6 2015
.SYNOPSIS...UNSETTLED WEATHER IS EXPECTED MUCH OF THIS WEEK. AN
EAST WEST FRONTAL BOUNDARY WILL SPEND THIS AFTERNOON JUST NORTH
OF THE MOHAWK VALLEY. TO ITS SOUTH TODAY WILL BE MILD AND PARTLY
SUNNY...WHILE CLOUDS...SPOTTY SHOWERS AND COOLER WEATHER WILL BE
THE RULE TO ITS NORTH. TONIGHT AND TUESDAY IT WILL SAG SOUTH...STALLING
FROM OHIO TO DELMARVA...BEFORE SURGING BACK NORTH THURSDAY NIGHT.
IT WILL PROVIDE THE FOCUS FOR COOL AND DREARY WEATHER WITH PERIODS
OF MOSTLY LIGHT RAIN FOR MUCH OF THE WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 645 AM EDT...EVEN THOUGH CURRENT RADAR DISPLAYS SHOW LOTS OF
ECHOES TO THE NORTH OF I-90...BASED ON SURFACE REPORTS IT APPEARS
LITTLE IF ANY OF THIS PCPN IS REACHING THE GROUND. WILL CONTINUE
WITH ONLY SLIGHT TO LOW CHANCE POPS FOR THIS REGION FOR TODAY.
THE LATEST HRRR INDICATED THIS ACTIVITY MOVING NORTH AND
DISSIPATING. OTHERWISE MOST AREAS WILL HAVE A DRY DAY WITH PLENTY
OF SUNSHINE FROM I-90 SOUTHWARD BY THIS AFTERNOON.
HIGHS TODAY IN MOST AREAS WILL BE IN THE MID OR UPPER 50S.
FURTHER NORTH...WITH MORE CLOUDS AND BETTER CHANCES FOR LIGHT
SHOWERS...WE HELD HIGH TEMPERATURES FROM THE MID 40S TO LOWER 50S.
THE WIND WILL TURN SOUTHERLY IN MOST AREAS TODAY...5-15 MPH HELPING
TO BRING IN THOSE MILDER TEMPERATURES.
NOT A BAD START TO THE WORKWEEK WEATHERWISE...BUT THE WEATHER LOOKS
UNSETTLED FOR THE REMAINDER OF THE SHORT TERM PERIOD.
A DISTURBANCE OVER IOWA WILL HEAD EAST. AT THE SAME TIME...HIGH
PRESSURE OVER WHICH WILL ACTUALLY BEGIN TUGGING THE FRONT SLIGHTLY
SOUTHWARD AS HIGH PRESSURE SOUTHWEST OF SAMES BAY WILL SLIP A BIT
SOUTHWARD...PUSHING THE FRONT BACK TO THE SOUTH OF OUR REGION BY
TUESDAY MORNING. BY THIS TIME...THE AFOREMENTIONED DISTURBANCE WILL
BE IN THE EASTERN OHIO VALLEY. THIS DISTURBANCE WILL INDUCE
ISENTROPIC LIFT INCREASE THE THREAT OF RAIN OR SHOWERS TONIGHT AND
ESPECIALLY ON TUESDAY.
AS COLD SHALLOW AIR FILTERS IN FIRST TO OUR NORTH TONIGHT...THERE IS
A CHANCE OF A LITTLE FREEZING RAIN OVER THE ADIRONDACKS EASTWARD TO
ABOUT LAKE GEORGE. WE WILL MONITOR THIS POSSIBILITY AND ISSUE ANY
HEADLINES IF NECESSARY. LOWS WILL BE FREEZING OR A LITTLE LOWER
NORTHERN AREAS...MID TO UPPER 30S JUST TO THE NORTH OF THE CAPITAL
REGION INCLUDING SOUTHERN VERMONT...40-45 ALBANY SOUTH.
TUESDAY WILL SEE THE BEST CHANCE OF RAIN SLIP SOUTH OF THE CAPITAL
REGION...BUT CHANCES NORTH. IT LOOKS TO BE AN OVERCAST DAY...RAW
NORTH OF ALBANY WITH HIGHS IN THE 40S...TO AROUND 50 IN AND AROUND
ALBANY...LOWER 50S SOUTH.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
AT 500HPA HEIGHTS BUILD...AND RIDGING DEVELOPS OVER THE EASTERN
USA TO START THIS PERIOD. MEANWHILE AT SFC AND LLVLS COOL SFC
HIGH PRESSURE WILL BE ACROSS S ONT AND QB WITH APPALACHIAN
DAMMING BCMG ESTABLISHED ACROSS THE EASTERN SEABOARD S TO VA.
WITH CDFNT JUST S OF I70 TUES NT. AT FIRST DRIER COOLER AIR MAY
FILTER INTO N TIER OF FCA WITH HIGH TO OUR N...WHILE CLOUDS AND
SCT -SHRA PERSIST ACROSS S AREASNEAR FRONTAL BOUNDARY. WED MODEST
SFC CLYCGEN ENSUES OFFSHORE BUT THE MAIN FORCING FOR PCPN WILL BE
COOL AIR DAMMED ALONG E SEABOARD AND ITS ASSOC COASTAL FRONTS TO
THE S & E...AND THE MAIN FRONT SHIFTING BACK N WED AND WED NT TO
OUR SW. FOR THE MOST PART THIS PERIOD WILL BE CLOUDY WITH SOME
PERIODS OF LIGHT PCPN...MAINLY RAIN BUT CANT RULE OUT SOME -SN
OVER HIGH TRRN AT NIGHT.
BY THU WITH A RIDGE BUILDING AT 500HPA...A SHORT WV RIDING OVER
THE TOP OF THE 500HPA RIDGE...A DEEPENING 500HPA TROF OVER GRT
PLAINS WITH STRONG CYCLOGENISUS...THE WMFNT WILL SURGE N THRU THE
REGION THU AND THU NT WITH A DISTINCT PERIOD OF RAIN.
QPF AMNTS ARE ON THE ORDER OF AN INCH IN THE DETERMINISTIC MODELS
AND MOST OF THE SREF/GEFS ENSEMBLE MEMBERS FOR THIS PERIOD WITH
THE OPERATIONAL GFS PUSHES THE TOTAL TO CLOSE TO 2 INCHES. ITS
CLEARLY AN OUTLIER ON THIS RUN...AND HAS BEEN OVER DOING THE QPF
ON THIS SYSTEM FOR DAYS.
OVERALL A DREARY COOL BUT NOT TOO COOL PERIOD...LOTS OF
CLOUDS...PERIODS OF MAINLY -RN...BEST CHC FOR A WIDESPREAD RN
APPEARS TO BE LATE THU. TEMPS WILL RUN 5 TO 10 DE3G BLO NORMAL
WITH HIGHS IN THE 40S...SOME 50S SOUTH. LOWS WILL BE IN THE
30S...SOME 20S NORTH.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
PER THE GLOBAL MODEL CONSENSUS...THIS STRONG WAVE MOVES OUT ONTO
THE PLAINS WITH A STRONG LOW LEVEL JET RESPONSE AND GULF OF MEXICO
MOISTURE RETURN FOR MORE CLOUDS AND WET CONDITIONS FOR THE REGION
LATER THURSDAY AND CONTINUING INTO FRIDAY. WE WILL KEEP LIKELY
POPS AT THIS TIME ACROSS THE ENTIRE CWFA. WHILE MOST OF THE
PRECIPITATION WILL FALL AS A LIQUID...WE CONTINUE TO WATCH TRENDS
OF THE SURFACE HIGH TRACKING ACROSS SOUTHEAST CANADA THROUGH
EXTREME NORTHERN NEW ENGLAND. THIS MAY RESULT IN A PERIOD OF
WINTRY MIXTURE WELL TO THE NORTH AND EAST OF I90.
FRIDAY NIGHT THE TRENDS FAVOR A DRY SLOT AS MAIN SURFACE LOW TRACKS
WELL TO OUR WEST AND NORTH AS MAIN UPPER TROUGH AXIS REMAINS
UPSTREAM. SO WE WILL LOWER POPS ACCORDINGLY WITH PORTIONS OF THE
DACKS REMAINING UNDER CHC-SCT POPS. THIS UPPER TROUGH AXIS SLOWLY
TRANSVERSES THE REGION THROUGH THE WEEKEND WITH MAINLY DIURNALLY
DRIVEN SHOWERS WITH THE BEST POTENTIAL ACROSS THE HIGHER TERRAIN.
AS FOR TEMPERATURES THROUGH THE PERIOD...WE HAVE FOLLOWED THE
BLENDED APPROACH OFFERED BY WPC WITH A SLIGHT WARMER TREND DURING
THE OVERNIGHT PERIODS THROUGH THE WEEK DUE TO CLOUD COVER AND WARM
ADVECTION REGIME.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
SKIES CLEARED OUT IN THE MID HUDSON VALLEY WHICH ALLOWED FOR IFR
CONDITIONS TO EVOLVE RATHER QUICKLY AT KPOU. ELSEWHERE IT APPEARS
VFR CONDITIONS HAVE PREVAILED DUE TO THE CLOUD COVERAGE. AS THE
WARM FRONT CONTINUES TO LIFT SLOWLY NORTH...FOG AT KPOU WILL QUICKLY
DISSIPATE WITH VFR CONDITIONS EXPECTED AT ALL TAF SITES FROM MID
MORNING ON.
CLOUDS WILL INCREASE LATER THIS AFTERNOON AND ESPECIALLY BY SUNSET.
THE CHANCE FOR SHOWERS WILL INCREASE FROM WEST TO EAST THIS EVENING
AND THROUGH THE OVERNIGHT PERIOD AS A WEAK WAVE OF LOW PRESSURE
MOVES ALONG THE FRONTAL BOUNDARY. THIS WILL BRING A PERIOD OF MVFR
CIGS AND VIS TO ALL TAF SITES EARLY TONIGHT...THEN IFR LATE TONIGHT.
LIGHT AND VARIABLE WINDS THIS EARLY MONDAY MORNING...BECOMING
SOUTHERLY THROUGH DAYLIGHT HOURS AT SPEEDS 10KTS OR LESS. TONIGHT
THE WINDS SUBSIDE TO LIGHT AND VARIABLE ONCE AGAIN.
OUTLOOK...
TUESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA.
WEDNESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. LIKELY SHRA.
FRIDAY: MODERATE OPERATIONAL IMPACT. LIKELY SHRA.
FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
&&
.FIRE WEATHER...
TODAY LOOKS MAINLY DRY...EXCEPT NORTHERN AREAS WILL MIGHT SEE A
LITTLE RAINFALL. PARTIAL SUNSHINE AND MINIMUM RH VALUES 35-40
PERCENT CAN BE EXPECTED SOUTH OF I-90...LESS SUNSHINE AND 40-50
PERCENT VALUES NEAR I-90. NORTH OF THE CAPITAL REGION WILL FEATURE
MORE CLOUDS AND THE THREAT OF LIGHT SHOWERS NORTH OF A FRONTAL
BOUNDARY. RH VALUES WILL BE MORE ELEVATED ONLY DROPPING TO THE 50-60
PERCENT RANGE THIS AFTERNOON.
A SOUTH WIND WILL AVERAGE 5-15 MPH FROM I-90 SOUTH...LIGHT AND
VARIABLE FURTHER NORTH NEAR THE FRONT.
THIS FRONT WILL DRIVE OUR WEATHER FOR THE REMAINDER OF THE WEEK. IT
LOOKS MORE UNSETTLED TONIGHT THROUGH THURSDAY WITH PERIODS OF RAIN
EXPECTED AND DAMP CONDITIONS. BY FRIDAY...MOST IF NOT ALL PLACES
SHOULD HAVE SEEN OVER A QUARTER INCH OF RAINFALL. IT LOOKS TO TURN
DRIER BY NEXT WEEKEND.
&&
.HYDROLOGY...
THE FLOOD WARNING FOR THE MOHAWK RIVER AT THE UTICA HARBOR FOR MINOR
FLOODING REMAINS IN EFFECT...BUT COULD BE DROPPED LATER THIS MORNING.
IT NOW LOOKS MAINLY DRY FROM I-90 SOUTH TODAY...WITH SOME LIGHT RAIN
OR SHOWERS NORTH OF I-90 WITH QPF AMOUNTS GENERALLY UNDER A TENTH OF
AN INCH. THIS RAIN WILL HAVE NO ADDED IMPACT ON ALREADY SWOLLEN
STREAMS AND RIVERS.
A STALLED OUT FRONT WILL BECOME MORE ACTIVE AND MOISTURE INCREASES
NEAR IT...AND SEVERAL DISTURBANCES MOVE ALONG IT TONIGHT THROUGH
LATE THURSDAY. MOST OF THE PRECIPITATION WILL FALL AS LIQUID
RAIN...BUT THERE COULD BE SOME SLEET...FREEZING RAIN OR EVEN SNOW IN
OUR NORTHERN AREAS AT NIGHT.
THERE WILL CONTINUE TO BE DIURNAL MELTING OF THE SNOWPACK WITH
TEMPERATURES MOST NIGHTS GETTING COLD ENOUGH SLOW AND EVEN STOP THE
MELT.
THE PRECIPITATION WILL BE LIGHT THROUGH MONDAY NIGHT WITH QPF
AMOUNTS OF A QUARTER INCH OF LESS EXPECTED. HOWEVER MORE SIGNIFICANT
QPF IS EXPECTED TUESDAY AND TUESDAY NIGHT WITH UP TO AN ONE INCH
POSSIBLE. MORE RAINFALL IS EXPECTED WEDNESDAY. THIS RAINFALL COMBINED
WITH RUNOFF FROM SNOWMELT WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. THE METEOROLOGICAL MODEL ENSEMBLE ROVER FORECASTS (MMEFS)
INDICATES THERE IS THE POSSIBILITY OF SOME RIVER POINTS REACHING
ACTION OR PERHAPS EVEN MINOR FLOOD FLOOD STAGE. CONFIDENCE IS NOT
HIGH FOR QPF AMOUNTS AND IS EVEN LOWER FOR THE EXPECTED RUNOFF FROM
SNOWMELT. HAVE ADDED MENTION TO OUR HAZARDOUS WEATHER OUTLOOK.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...HWJIV/GJM
SHORT TERM...SNYDER
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...IAA/HWJIV
HYDROLOGY...IAA/HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
1021 AM EDT MON APR 6 2015
.SYNOPSIS...
.SYNOPSIS...HIGH PRESSURE WILL BRIEFLY BUILD IN TODAY...ESPECIALLY
SOUTH OF INTERSTATE 90 WHERE IT WILL BE PARTLY TO MOSTLY SUNNY...
MILD AND DRY. NORTH OF INTERSTATE 90...THERE IS A STALLED FRONT...
WHICH WILL RESULT IN MORE CLOUDS AND AN INCREASING CHANCE OF SHOWERS
THE FURTHER NORTH ONE GOES. TONIGHT...AS THE FRONT BEGINS TO SAG
SOUTHWARD...SHOWERS ARE POSSIBLE EVERYWHERE AND THERE COULD EVEN BE
A LITTLE FREEZING RAIN ACROSS THE ADIRONDACKS. UNSETTLED WEATHER
WILL BE WITH US TUESDAY THROUGH FRIDAY AS A SERIES OF DISTURBANCES
MOVE ALONG THE NEARLY STATIONARY FRONT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 645 AM EDT...EVEN THOUGH CURRENT RADAR DISPLAYS SHOW LOTS OF
ECHOES TO THE NORTH OF I-90...BASED ON SURFACE REPORTS IT APPEARS
LITTLE IF ANY OF THIS PCPN IS REACHING THE GROUND. WILL CONTINUE
WITH ONLY SLIGHT TO LOW CHANCE POPS FOR THIS REGION FOR TODAY.
THE LATEST HRRR INDICATED THIS ACTIVITY MOVING NORTH AND
DISSIPATING. OTHERWISE MOST AREAS WILL HAVE A DRY DAY WITH PLENTY
OF SUNSHINE FROM I-90 SOUTHWARD BY THIS AFTERNOON.
HIGHS TODAY IN MOST AREAS WILL BE IN THE MID OR UPPER 50S.
FURTHER NORTH...WITH MORE CLOUDS AND BETTER CHANCES FOR LIGHT
SHOWERS...WE HELD HIGH TEMPERATURES FROM THE MID 40S TO LOWER 50S.
THE WIND WILL TURN SOUTHERLY IN MOST AREAS TODAY...5-15 MPH HELPING
TO BRING IN THOSE MILDER TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
NOT A BAD START TO THE WORKWEEK WEATHERWISE...BUT THE WEATHER LOOKS
UNSETTLED FOR THE REMAINDER OF THE SHORT TERM PERIOD.
A DISTURBANCE OVER IOWA WILL HEAD EAST. AT THE SAME TIME...HIGH
PRESSURE OVER WHICH WILL ACTUALLY BEGIN TUGGING THE FRONT SLIGHTLY
SOUTHWARD AS HIGH PRESSURE SOUTHWEST OF SAMES BAY WILL SLIP A BIT
SOUTHWARD...PUSHING THE FRONT BACK TO THE SOUTH OF OUR REGION BY
TUESDAY MORNING. BY THIS TIME...THE AFOREMENTIONED DISTURBANCE WILL
BE IN THE EASTERN OHIO VALLEY. THIS DISTURBANCE WILL INDUCE
ISENTROPIC LIFT INCREASE THE THREAT OF RAIN OR SHOWERS TONIGHT AND
ESPECIALLY ON TUESDAY.
AS COLD SHALLOW AIR FILTERS IN FIRST TO OUR NORTH TONIGHT...THERE IS
A CHANCE OF A LITTLE FREEZING RAIN OVER THE ADIRONDACKS EASTWARD TO
ABOUT LAKE GEORGE. WE WILL MONITOR THIS POSSIBILITY AND ISSUE ANY
HEADLINES IF NECESSARY. LOWS WILL BE FREEZING OR A LITTLE LOWER
NORTHERN AREAS...MID TO UPPER 30S JUST TO THE NORTH OF THE CAPITAL
REGION INCLUDING SOUTHERN VERMONT...40-45 ALBANY SOUTH.
TUESDAY WILL SEE THE BEST CHANCE OF RAIN SLIP SOUTH OF THE CAPITAL
REGION...BUT CHANCES NORTH. IT LOOKS TO BE AN OVERCAST DAY...RAW
NORTH OF ALBANY WITH HIGHS IN THE 40S...TO AROUND 50 IN AND AROUND
ALBANY...LOWER 50S SOUTH.
TUESDAY NIGHT HIGH PRESSURE TO OUR NORTH WILL WEDGE SHALLOW COLD AIR
INTO MUCH OF THE REGION...WITH STILL PLENTY OF LOW LEVEL MOISTURE. WE
KEPT CHANCES FOR PRECIPITATION ACROSS THE ENTIRE AREA. ANY
PRECIPITATION THAT FALLS SHOULD BE IN THE FORM FOR SNOW NORTH OF
ALBANY...RAIN FURTHER SOUTH. HOWEVER...PRECIPITATION ON TUESDAY
NIGHT LOOKS LIGHT. LOWS 25-32 NORTH OF ALBANY...33 TO ABOUT 38
ALBANY SOUTH.
ANOTHER DISTURBANCE LOOKS TO PRODUCE MORE RAIN ON WEDNESDAY. THIS
ONE LOOKS STRONGER...AND WILL PRODUCE STRONGER ISENTROPIC LIFT AS
THE SURFACE BOUNDARY LOOKS TO REMAIN SOUTH OF I84. THERE IS A GOOD
CHANCE OF MORE RAIN THAT DAY. HIGHS WILL ONLY BE IN THE 40S...MAYBE
SOME LOWER 50S NEAR INTERSTATE 84. AS LOW PRESSURE PUSH TO OUR EAST
LATE WEDNESDAY NIGHT...PRECIPITATION MIGHT END AS SOME SNOW SHOWERS
ACROSS ALL AREAS AS LOWS DIP DOWN FROM THE UPPER 20S NORTH TO MID
30S SOUTH.
THE QPF TUESDAY AND TUESDAY NIGHT AND AGAIN WEDNESDAY WILL BE MORE
SIGNIFICANT AND AT THIS TIME IT APPEARS THAT QPF AMOUNTS UP TO AN
ONE INCH ARE POSSIBLE. THIS WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. REFER TO HYDROLOGY SECTION FOR MORE DETAILS. WE WILL
CONTINUE TO MENTION IN OUR HAZARDOUS WEATHER OUTLOOK (HWO).
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN ACTIVE PERIOD OF WEATHER REMAINS IN THE FORECAST AS THE SYNOPTIC
FLOW AMPLIFIES ACROSS THE WESTERN CONUS AS A STRONGER WAVE COMES
ASHORE ACROSS PACIFIC COAST.
PER THE GLOBAL MODEL CONSENSUS...THIS STRONG WAVE MOVES OUT ONTO THE
PLAINS WITH A STRONG LOW LEVEL JET RESPONSE AND GULF OF MEXICO
MOISTURE RETURN FOR MORE CLOUDS AND WET CONDITIONS FOR THE REGION
LATER THURSDAY AND CONTINUING INTO FRIDAY. WE WILL KEEP LIKELY POPS
AT THIS TIME ACROSS THE ENTIRE CWFA. WHILE MOST OF THE
PRECIPITATION WILL FALL AS A LIQUID...WE CONTINUE TO WATCH TRENDS OF
THE SURFACE HIGH TRACKING ACROSS SOUTHEAST CANADA THROUGH EXTREME
NORTHERN NEW ENGLAND. THIS MAY RESULT IN A PERIOD OF WINTRY MIXTURE
WELL TO THE NORTH AND EAST OF I90.
FRIDAY NIGHT THE TRENDS FAVOR A DRY SLOT AS MAIN SURFACE LOW TRACKS
WELL TO OUR WEST AND NORTH AS MAIN UPPER TROUGH AXIS REMAINS
UPSTREAM. SO WE WILL LOWER POPS ACCORDINGLY WITH PORTIONS OF THE
DACKS REMAINING UNDER CHC-SCT POPS. THIS UPPER TROUGH AXIS SLOWLY
TRANSVERSES THE REGION THROUGH THE WEEKEND WITH MAINLY DIURNALLY
DRIVEN SHOWERS WITH THE BEST POTENTIAL ACROSS THE HIGHER TERRAIN.
AS FOR TEMPERATURES THROUGH THE PERIOD...WE HAVE FOLLOWED THE
BLENDED APPROACH OFFERED BY WPC WITH A SLIGHT WARMER TREND DURING
THE OVERNIGHT PERIODS THROUGH THE WEEK DUE TO CLOUD COVER AND WARM
ADVECTION REGIME.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
SKIES CLEARED OUT IN THE MID HUDSON VALLEY WHICH ALLOWED FOR IFR
CONDITIONS TO EVOLVE RATHER QUICKLY AT KPOU. ELSEWHERE IT APPEARS
VFR CONDITIONS HAVE PREVAILED DUE TO THE CLOUD COVERAGE. AS THE
WARM FRONT CONTINUES TO LIFT SLOWLY NORTH...FOG AT KPOU WILL QUICKLY
DISSIPATE WITH VFR CONDITIONS EXPECTED AT ALL TAF SITES FROM MID
MORNING ON.
CLOUDS WILL INCREASE LATER THIS AFTERNOON AND ESPECIALLY BY SUNSET.
THE CHANCE FOR SHOWERS WILL INCREASE FROM WEST TO EAST THIS EVENING
AND THROUGH THE OVERNIGHT PERIOD AS A WEAK WAVE OF LOW PRESSURE
MOVES ALONG THE FRONTAL BOUNDARY. THIS WILL BRING A PERIOD OF MVFR
CIGS AND VIS TO ALL TAF SITES EARLY TONIGHT...THEN IFR LATE TONIGHT.
LIGHT AND VARIABLE WINDS THIS EARLY MONDAY MORNING...BECOMING
SOUTHERLY THROUGH DAYLIGHT HOURS AT SPEEDS 10KTS OR LESS. TONIGHT
THE WINDS SUBSIDE TO LIGHT AND VARIABLE ONCE AGAIN.
OUTLOOK...
TUESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA.
WEDNESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. LIKELY SHRA.
FRIDAY: MODERATE OPERATIONAL IMPACT. LIKELY SHRA.
FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
&&
.FIRE WEATHER...
TODAY LOOKS MAINLY DRY...EXCEPT NORTHERN AREAS WILL MIGHT SEE A
LITTLE RAINFALL. PARTIAL SUNSHINE AND MINIMUM RH VALUES 35-40
PERCENT CAN BE EXPECTED SOUTH OF I-90...LESS SUNSHINE AND 40-50
PERCENT VALUES NEAR I-90. NORTH OF THE CAPITAL REGION WILL FEATURE
MORE CLOUDS AND THE THREAT OF LIGHT SHOWERS NORTH OF A FRONTAL
BOUNDARY. RH VALUES WILL BE MORE ELEVATED ONLY DROPPING TO THE 50-60
PERCENT RANGE THIS AFTERNOON.
A SOUTH WIND WILL AVERAGE 5-15 MPH FROM I-90 SOUTH...LIGHT AND
VARIABLE FURTHER NORTH NEAR THE FRONT.
THIS FRONT WILL DRIVE OUR WEATHER FOR THE REMAINDER OF THE WEEK. IT
LOOKS MORE UNSETTLED TONIGHT THROUGH THURSDAY WITH PERIODS OF RAIN
EXPECTED AND DAMP CONDITIONS. BY FRIDAY...MOST IF NOT ALL PLACES
SHOULD HAVE SEEN OVER A QUARTER INCH OF RAINFALL. IT LOOKS TO TURN
DRIER BY NEXT WEEKEND.
&&
.HYDROLOGY...
THE FLOOD WARNING FOR THE MOHAWK RIVER AT THE UTICA HARBOR FOR MINOR
FLOODING REMAINS IN EFFECT...BUT COULD BE DROPPED LATER THIS MORNING.
IT NOW LOOKS MAINLY DRY FROM I-90 SOUTH TODAY...WITH SOME LIGHT RAIN
OR SHOWERS NORTH OF I-90 WITH QPF AMOUNTS GENERALLY UNDER A TENTH OF
AN INCH. THIS RAIN WILL HAVE NO ADDED IMPACT ON ALREADY SWOLLEN
STREAMS AND RIVERS.
A STALLED OUT FRONT WILL BECOME MORE ACTIVE AND MOISTURE INCREASES
NEAR IT...AND SEVERAL DISTURBANCES MOVE ALONG IT TONIGHT THROUGH
LATE THURSDAY. MOST OF THE PRECIPITATION WILL FALL AS LIQUID
RAIN...BUT THERE COULD BE SOME SLEET...FREEZING RAIN OR EVEN SNOW IN
OUR NORTHERN AREAS AT NIGHT.
THERE WILL CONTINUE TO BE DIURNAL MELTING OF THE SNOWPACK WITH
TEMPERATURES MOST NIGHTS GETTING COLD ENOUGH SLOW AND EVEN STOP THE
MELT.
THE PRECIPITATION WILL BE LIGHT THROUGH MONDAY NIGHT WITH QPF
AMOUNTS OF A QUARTER INCH OF LESS EXPECTED. HOWEVER MORE SIGNIFICANT
QPF IS EXPECTED TUESDAY AND TUESDAY NIGHT WITH UP TO AN ONE INCH
POSSIBLE. MORE RAINFALL IS EXPECTED WEDNESDAY. THIS RAINFALL COMBINED
WITH RUNOFF FROM SNOWMELT WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. THE METEOROLOGICAL MODEL ENSEMBLE ROVER FORECASTS (MMEFS)
INDICATES THERE IS THE POSSIBILITY OF SOME RIVER POINTS REACHING
ACTION OR PERHAPS EVEN MINOR FLOOD FLOOD STAGE. CONFIDENCE IS NOT
HIGH FOR QPF AMOUNTS AND IS EVEN LOWER FOR THE EXPECTED RUNOFF FROM
SNOWMELT. HAVE ADDED MENTION TO OUR HAZARDOUS WEATHER OUTLOOK.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV/GJM
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...IAA/HWJIV
HYDROLOGY...IAA/HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
737 AM EDT MON APR 6 2015
.SYNOPSIS...
HIGH PRESSURE FROM THE SOUTH WILL ATTEMPT TO BRIEFLY
BUILD IN TODAY... SOUTH OF INTERSTATE 90 WHERE IT LOOKS TO BE PARTLY
SUNNY MILD AND DRY. FROM ALBANY NORTHWARD...WHERE A FRONT WILL BE
STALLED...THERE WILL BE MORE IN THE WAY OF CLOUDS AND AN INCREASING
CHANCE OF SHOWERS THE FURTHER NORTH ONE GOES. TONIGHT AS THE FRONT
BEGINS TO SAG SOUTHWARD SHOWERS ARE POSSIBLE EVERYWHERE AND THERE
COULD EVEN BE A LITTLE FREEZING RAIN ACROSS THE ADIRONDACKS.
UNSETTLED WEATHER WILL BE WITH US TUESDAY THROUGH FRIDAY AS A SERIES
OF DISTURBANCES WORK ALONG THE NEARLY STATIONARY FRONT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 645 AM EDT...JUST A FEW WIDELY SCATTERED LIGHT RAIN OR SNOW
SHOWERS OVER OUR NORTHERN AREAS PRODUCING LITTLE IF ANY MEASURABLE
PRECIPITATION. TEMPERATURES RANGED FROM THE MID 20S NORTH TO THE MID
30S SOUTH.
THE LATEST HRRR INDICATED THIS ACTIVITY MOVING NORTH AND
DISSIPATING. OTHERWISE MANY AREAS MIGHT SEE A DRY DRY WITH SOME
SUNSHINE FROM I-90 SOUTHWARD. THEREFORE OUR FORECAST TODAY IS MORE
OPTIMISTIC THAN THE PREVIOUS ONE AS A BOUNDARY LIFTS JUST NORTH OF I-
90 AND INITIALLY WEAKENS.
WE STILL HAVE SLIGHT POPS ACROSS THE CAPITAL REGION...LOW POPS NORTH
MUCH OF THE DAY. THEREFORE...WE HAVE RAISED TEMPERATURES A LITTLE IN
SOME PLACES COMPARED TO YESTERDAY AS WELL. AREAS WELL SOUTH OF I-90
LOOK TO CRACK 60 OR A LITTLE BETTER. EVEN IN THE CAPITAL
REGION...TEMPERATURES SHOULD GET A NICE BUMP TODAY COMPARED TO
SUNDAY...WITH HIGHS IN THE MID OR UPPER 50S. FURTHER NORTH...WITH
MORE CLOUDS AND BETTER CHANCES FOR LIGHT SHOWERS...WE HELD HIGH
TEMPERATURES FROM THE MID 40S TO LOWER 50S.
THE WIND WILL TURN SOUTHERLY IN MOST AREAS TODAY...5-15 MPH HELPING
TO BRING IN THOSE MILDER TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
NOT A BAD START TO THE WORKWEEK WEATHERWISE...BUT THE WEATHER LOOKS
UNSETTLED FOR THE REMAINDER OF THE SHORT TERM PERIOD.
A DISTURBANCE OVER IOWA WILL HEAD EAST. AT THE SAME TIME...HIGH
PRESSURE OVER WHICH WILL ACTUALLY BEGIN TUGGING THE FRONT SLIGHTLY
SOUTHWARD AS HIGH PRESSURE SOUTHWEST OF SAMES BAY WILL SLIP A BIT
SOUTHWARD...PUSHING THE FRONT BACK TO THE SOUTH OF OUR REGION BY
TUESDAY MORNING. BY THIS TIME...THE AFOREMENTIONED DISTURBANCE WILL
BE IN THE EASTERN OHIO VALLEY. THIS DISTURBANCE WILL INDUCE
ISENTROPIC LIFT INCREASE THE THREAT OF RAIN OR SHOWERS TONIGHT AND
ESPECIALLY ON TUESDAY.
AS COLD SHALLOW AIR FILTERS IN FIRST TO OUR NORTH TONIGHT...THERE IS
A CHANCE OF A LITTLE FREEZING RAIN OVER THE ADIRONDACKS EASTWARD TO
ABOUT LAKE GEORGE. WE WILL MONITOR THIS POSSIBILITY AND ISSUE ANY
HEADLINES IF NECESSARY. LOWS WILL BE FREEZING OR A LITTLE LOWER
NORTHERN AREAS...MID TO UPPER 30S JUST TO THE NORTH OF THE CAPITAL
REGION INCLUDING SOUTHERN VERMONT...40-45 ALBANY SOUTH.
TUESDAY WILL SEE THE BEST CHANCE OF RAIN SLIP SOUTH OF THE CAPITAL
REGION...BUT CHANCES NORTH. IT LOOKS TO BE AN OVERCAST DAY...RAW
NORTH OF ALBANY WITH HIGHS IN THE 40S...TO AROUND 50 IN AND AROUND
ALBANY...LOWER 50S SOUTH.
TUESDAY NIGHT HIGH PRESSURE TO OUR NORTH WILL WEDGE SHALLOW COLD AIR
INTO MUCH OF THE REGION...WITH STILL PLENTY OF LOW LEVEL MOISTURE. WE
KEPT CHANCES FOR PRECIPITATION ACROSS THE ENTIRE AREA. ANY
PRECIPITATION THAT FALLS SHOULD BE IN THE FORM FOR SNOW NORTH OF
ALBANY...RAIN FURTHER SOUTH. HOWEVER...PRECIPITATION ON TUESDAY
NIGHT LOOKS LIGHT. LOWS 25-32 NORTH OF ALBANY...33 TO ABOUT 38
ALBANY SOUTH.
ANOTHER DISTURBANCE LOOKS TO PRODUCE MORE RAIN ON WEDNESDAY. THIS
ONE LOOKS STRONGER...AND WILL PRODUCE STRONGER ISENTROPIC LIFT AS
THE SURFACE BOUNDARY LOOKS TO REMAIN SOUTH OF I84. THERE IS A GOOD
CHANCE OF MORE RAIN THAT DAY. HIGHS WILL ONLY BE IN THE 40S...MAYBE
SOME LOWER 50S NEAR INTERSTATE 84. AS LOW PRESSURE PUSH TO OUR EAST
LATE WEDNESDAY NIGHT...PRECIPITATION MIGHT END AS SOME SNOW SHOWERS
ACROSS ALL AREAS AS LOWS DIP DOWN FROM THE UPPER 20S NORTH TO MID
30S SOUTH.
THE QPF TUESDAY AND TUESDAY NIGHT AND AGAIN WEDNESDAY WILL BE MORE
SIGNIFICANT AND AT THIS TIME IT APPEARS THAT QPF AMOUNTS UP TO AN
ONE INCH ARE POSSIBLE. THIS WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. REFER TO HYDROLOGY SECTION FOR MORE DETAILS. WE WILL
CONTINUE TO MENTION IN OUR HAZARDOUS WEATHER OUTLOOK (HWO).
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN ACTIVE PERIOD OF WEATHER REMAINS IN THE FORECAST AS THE SYNOPTIC
FLOW AMPLIFIES ACROSS THE WESTERN CONUS AS A STRONGER WAVE COMES
ASHORE ACROSS PACIFIC COAST.
PER THE GLOBAL MODEL CONSENSUS...THIS STRONG WAVE MOVES OUT ONTO THE
PLAINS WITH A STRONG LOW LEVEL JET RESPONSE AND GULF OF MEXICO
MOISTURE RETURN FOR MORE CLOUDS AND WET CONDITIONS FOR THE REGION
LATER THURSDAY AND CONTINUING INTO FRIDAY. WE WILL KEEP LIKELY POPS
AT THIS TIME ACROSS THE ENTIRE CWFA. WHILE MOST OF THE
PRECIPITATION WILL FALL AS A LIQUID...WE CONTINUE TO WATCH TRENDS OF
THE SURFACE HIGH TRACKING ACROSS SOUTHEAST CANADA THROUGH EXTREME
NORTHERN NEW ENGLAND. THIS MAY RESULT IN A PERIOD OF WINTRY MIXTURE
WELL TO THE NORTH AND EAST OF I90.
FRIDAY NIGHT THE TRENDS FAVOR A DRY SLOT AS MAIN SURFACE LOW TRACKS
WELL TO OUR WEST AND NORTH AS MAIN UPPER TROUGH AXIS REMAINS
UPSTREAM. SO WE WILL LOWER POPS ACCORDINGLY WITH PORTIONS OF THE
DACKS REMAINING UNDER CHC-SCT POPS. THIS UPPER TROUGH AXIS SLOWLY
TRANSVERSES THE REGION THROUGH THE WEEKEND WITH MAINLY DIURNALLY
DRIVEN SHOWERS WITH THE BEST POTENTIAL ACROSS THE HIGHER TERRAIN.
AS FOR TEMPERATURES THROUGH THE PERIOD...WE HAVE FOLLOWED THE
BLENDED APPROACH OFFERED BY WPC WITH A SLIGHT WARMER TREND DURING
THE OVERNIGHT PERIODS THROUGH THE WEEK DUE TO CLOUD COVER AND WARM
ADVECTION REGIME.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SKIES CLEARED OUT IN THE MID HUDSON VALLEY WHICH ALLOWED FOR IFR
CONDITIONS TO EVOLVE RATHER QUICKLY AT KPOU. ELSEWHERE IT APPEARS
VFR CONDITIONS HAVE PREVAILED DUE TO THE CLOUD COVERAGE. AS THE
WARM FRONT CONTINUES TO LIFT SLOWLY NORTH...FOG AT KPOU WILL QUICKLY
DISSIPATE WITH VFR CONDITIONS EXPECTED AT ALL TAF SITES FROM MID
MORNING ON.
CLOUDS WILL INCREASE LATER THIS AFTERNOON AND ESPECIALLY BY SUNSET.
THE CHANCE FOR SHOWERS WILL INCREASE FROM WEST TO EAST THIS EVENING
AND THROUGH THE OVERNIGHT PERIOD AS A WEAK WAVE OF LOW PRESSURE
MOVES ALONG THE FRONTAL BOUNDARY. THIS WILL BRING A PERIOD OF MVFR
CIGS AND VIS TO ALL TAF SITES EARLY TONIGHT...THEN IFR LATE TONIGHT.
LIGHT AND VARIABLE WINDS THIS EARLY MONDAY MORNING...BECOMING
SOUTHERLY THROUGH DAYLIGHT HOURS AT SPEEDS 10KTS OR LESS. TONIGHT
THE WINDS SUBSIDE TO LIGHT AND VARIABLE ONCE AGAIN.
OUTLOOK...
TUESDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA.
WEDNESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. LIKELY SHRA.
FRIDAY: MODERATE OPERATIONAL IMPACT. LIKELY SHRA.
FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
&&
.FIRE WEATHER...
TODAY LOOKS MAINLY DRY...EXCEPT NORTHERN AREAS WILL MIGHT SEE A
LITTLE RAINFALL. PARTIAL SUNSHINE AND MINIMUM RH VALUES 35-40
PERCENT CAN BE EXPECTED SOUTH OF I-90...LESS SUNSHINE AND 40-50
PERCENT VALUES NEAR I-90. NORTH OF THE CAPITAL REGION WILL FEATURE
MORE CLOUDS AND THE THREAT OF LIGHT SHOWERS NORTH OF A FRONTAL
BOUNDARY. RH VALUES WILL BE MORE ELEVATED ONLY DROPPING TO THE 50-60
PERCENT RANGE THIS AFTERNOON.
A SOUTH WIND WILL AVERAGE 5-15 MPH FROM I-90 SOUTH...LIGHT AND
VARIABLE FURTHER NORTH NEAR THE FRONT.
THIS FRONT WILL DRIVE OUR WEATHER FOR THE REMAINDER OF THE WEEK. IT
LOOKS MORE UNSETTLED TONIGHT THROUGH THURSDAY WITH PERIODS OF RAIN
EXPECTED AND DAMP CONDITIONS. BY FRIDAY...MOST IF NOT ALL PLACES
SHOULD HAVE SEEN OVER A QUARTER INCH OF RAINFALL. IT LOOKS TO TURN
DRIER BY NEXT WEEKEND.
&&
.HYDROLOGY...
THE FLOOD WARNING FOR THE MOHAWK RIVER AT THE UTICA HARBOR FOR MINOR
FLOODING REMAINS IN EFFECT...BUT COULD BE DROPPED LATER THIS MORNING.
IT NOW LOOKS MAINLY DRY FROM I-90 SOUTH TODAY...WITH SOME LIGHT RAIN
OR SHOWERS NORTH OF I-90 WITH QPF AMOUNTS GENERALLY UNDER A TENTH OF
AN INCH. THIS RAIN WILL HAVE NO ADDED IMPACT ON ALREADY SWOLLEN
STREAMS AND RIVERS.
A STALLED OUT FRONT WILL BECOME MORE ACTIVE AND MOISTURE INCREASES
NEAR IT...AND SEVERAL DISTURBANCES MOVE ALONG IT TONIGHT THROUGH
LATE THURSDAY. MOST OF THE PRECIPITATION WILL FALL AS LIQUID
RAIN...BUT THERE COULD BE SOME SLEET...FREEZING RAIN OR EVEN SNOW IN
OUR NORTHERN AREAS AT NIGHT.
THERE WILL CONTINUE TO BE DIURNAL MELTING OF THE SNOWPACK WITH
TEMPERATURES MOST NIGHTS GETTING COLD ENOUGH SLOW AND EVEN STOP THE
MELT.
THE PRECIPITATION WILL BE LIGHT THROUGH MONDAY NIGHT WITH QPF
AMOUNTS OF A QUARTER INCH OF LESS EXPECTED. HOWEVER MORE SIGNIFICANT
QPF IS EXPECTED TUESDAY AND TUESDAY NIGHT WITH UP TO AN ONE INCH
POSSIBLE. MORE RAINFALL IS EXPECTED WEDNESDAY. THIS RAINFALL COMBINED
WITH RUNOFF FROM SNOWMELT WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. THE METEOROLOGICAL MODEL ENSEMBLE ROVER FORECASTS (MMEFS)
INDICATES THERE IS THE POSSIBILITY OF SOME RIVER POINTS REACHING
ACTION OR PERHAPS EVEN MINOR FLOOD FLOOD STAGE. CONFIDENCE IS NOT
HIGH FOR QPF AMOUNTS AND IS EVEN LOWER FOR THE EXPECTED RUNOFF FROM
SNOWMELT. HAVE ADDED MENTION TO OUR HAZARDOUS WEATHER OUTLOOK.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...IAA/HWJIV
HYDROLOGY...IAA/HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
645 AM EDT MON APR 6 2015
.SYNOPSIS...
HIGH PRESSURE FROM THE SOUTH WILL ATTEMPT TO BRIEFLY
BUILD IN TODAY... SOUTH OF INTERSTATE 90 WHERE IT LOOKS TO BE PARTLY
SUNNY MILD AND DRY. FROM ALBANY NORTHWARD...WHERE A FRONT WILL BE
STALLED...THERE WILL BE MORE IN THE WAY OF CLOUDS AND AN INCREASING
CHANCE OF SHOWERS THE FURTHER NORTH ONE GOES. TONIGHT AS THE FRONT
BEGINS TO SAG SOUTHWARD SHOWERS ARE POSSIBLE EVERYWHERE AND THERE
COULD EVEN BE A LITTLE FREEZING RAIN ACROSS THE ADIRONDACKS.
UNSETTLED WEATHER WILL BE WITH US TUESDAY THROUGH FRIDAY AS A SERIES
OF DISTURBANCES WORK ALONG THE NEARLY STATIONARY FRONT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 645 AM EDT...JUST A FEW WIDELY SCATTERED LIGHT RAIN OR SNOW
SHOWERS OVER OUR NORTHERN AREAS PRODUCING LITTLE IF ANY MEASURABLE
PRECIPITATION. TEMPERATURES RANGED FROM THE MID 20S NORTH TO THE MID
30S SOUTH.
THE LATEST HRRR INDICATED THIS ACTIVITY MOVING NORTH AND
DISSIPATING. OTHERWISE MANY AREAS MIGHT SEE A DRY DRY WITH SOME
SUNSHINE FROM I-90 SOUTHWARD. THEREFORE OUR FORECAST TODAY IS MORE
OPTIMISTIC THAN THE PREVIOUS ONE AS A BOUNDARY LIFTS JUST NORTH OF I-
90 AND INITIALLY WEAKENS.
WE STILL HAVE SLIGHT POPS ACROSS THE CAPITAL REGION...LOW POPS NORTH
MUCH OF THE DAY. THEREFORE...WE HAVE RAISED TEMPERATURES A LITTLE IN
SOME PLACES COMPARED TO YESTERDAY AS WELL. AREAS WELL SOUTH OF I-90
LOOK TO CRACK 60 OR A LITTLE BETTER. EVEN IN THE CAPITAL
REGION...TEMPERATURES SHOULD GET A NICE BUMP TODAY COMPARED TO
SUNDAY...WITH HIGHS IN THE MID OR UPPER 50S. FURTHER NORTH...WITH
MORE CLOUDS AND BETTER CHANCES FOR LIGHT SHOWERS...WE HELD HIGH
TEMPERATURES FROM THE MID 40S TO LOWER 50S.
THE WIND WILL TURN SOUTHERLY IN MOST AREAS TODAY...5-15 MPH HELPING
TO BRING IN THOSE MILDER TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
NOT A BAD START TO THE WORKWEEK WEATHERWISE...BUT THE WEATHER LOOKS
UNSETTLED FOR THE REMAINDER OF THE SHORT TERM PERIOD.
A DISTURBANCE OVER IOWA WILL HEAD EAST. AT THE SAME TIME...HIGH
PRESSURE OVER WHICH WILL ACTUALLY BEGIN TUGGING THE FRONT SLIGHTLY
SOUTHWARD AS HIGH PRESSURE SOUTHWEST OF SAMES BAY WILL SLIP A BIT
SOUTHWARD...PUSHING THE FRONT BACK TO THE SOUTH OF OUR REGION BY
TUESDAY MORNING. BY THIS TIME...THE AFOREMENTIONED DISTURBANCE WILL
BE IN THE EASTERN OHIO VALLEY. THIS DISTURBANCE WILL INDUCE
ISENTROPIC LIFT INCREASE THE THREAT OF RAIN OR SHOWERS TONIGHT AND
ESPECIALLY ON TUESDAY.
AS COLD SHALLOW AIR FILTERS IN FIRST TO OUR NORTH TONIGHT...THERE IS
A CHANCE OF A LITTLE FREEZING RAIN OVER THE ADIRONDACKS EASTWARD TO
ABOUT LAKE GEORGE. WE WILL MONITOR THIS POSSIBILITY AND ISSUE ANY
HEADLINES IF NECESSARY. LOWS WILL BE FREEZING OR A LITTLE LOWER
NORTHERN AREAS...MID TO UPPER 30S JUST TO THE NORTH OF THE CAPITAL
REGION INCLUDING SOUTHERN VERMONT...40-45 ALBANY SOUTH.
TUESDAY WILL SEE THE BEST CHANCE OF RAIN SLIP SOUTH OF THE CAPITAL
REGION...BUT CHANCES NORTH. IT LOOKS TO BE AN OVERCAST DAY...RAW
NORTH OF ALBANY WITH HIGHS IN THE 40S...TO AROUND 50 IN AND AROUND
ALBANY...LOWER 50S SOUTH.
TUESDAY NIGHT HIGH PRESSURE TO OUR NORTH WILL WEDGE SHALLOW COLD AIR
INTO MUCH OF THE REGION...WITH STILL PLENTY OF LOW LEVEL MOISTURE. WE
KEPT CHANCES FOR PRECIPITATION ACROSS THE ENTIRE AREA. ANY
PRECIPITATION THAT FALLS SHOULD BE IN THE FORM FOR SNOW NORTH OF
ALBANY...RAIN FURTHER SOUTH. HOWEVER...PRECIPITATION ON TUESDAY
NIGHT LOOKS LIGHT. LOWS 25-32 NORTH OF ALBANY...33 TO ABOUT 38
ALBANY SOUTH.
ANOTHER DISTURBANCE LOOKS TO PRODUCE MORE RAIN ON WEDNESDAY. THIS
ONE LOOKS STRONGER...AND WILL PRODUCE STRONGER ISENTROPIC LIFT AS
THE SURFACE BOUNDARY LOOKS TO REMAIN SOUTH OF I84. THERE IS A GOOD
CHANCE OF MORE RAIN THAT DAY. HIGHS WILL ONLY BE IN THE 40S...MAYBE
SOME LOWER 50S NEAR INTERSTATE 84. AS LOW PRESSURE PUSH TO OUR EAST
LATE WEDNESDAY NIGHT...PRECIPITATION MIGHT END AS SOME SNOW SHOWERS
ACROSS ALL AREAS AS LOWS DIP DOWN FROM THE UPPER 20S NORTH TO MID
30S SOUTH.
THE QPF TUESDAY AND TUESDAY NIGHT AND AGAIN WEDNESDAY WILL BE MORE
SIGNIFICANT AND AT THIS TIME IT APPEARS THAT QPF AMOUNTS UP TO AN
ONE INCH ARE POSSIBLE. THIS WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. REFER TO HYDROLOGY SECTION FOR MORE DETAILS. WE WILL
CONTINUE TO MENTION IN OUR HAZARDOUS WEATHER OUTLOOK (HWO).
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN ACTIVE PERIOD OF WEATHER REMAINS IN THE FORECAST AS THE SYNOPTIC
FLOW AMPLIFIES ACROSS THE WESTERN CONUS AS A STRONGER WAVE COMES
ASHORE ACROSS PACIFIC COAST.
PER THE GLOBAL MODEL CONSENSUS...THIS STRONG WAVE MOVES OUT ONTO THE
PLAINS WITH A STRONG LOW LEVEL JET RESPONSE AND GULF OF MEXICO
MOISTURE RETURN FOR MORE CLOUDS AND WET CONDITIONS FOR THE REGION
LATER THURSDAY AND CONTINUING INTO FRIDAY. WE WILL KEEP LIKELY POPS
AT THIS TIME ACROSS THE ENTIRE CWFA. WHILE MOST OF THE
PRECIPITATION WILL FALL AS A LIQUID...WE CONTINUE TO WATCH TRENDS OF
THE SURFACE HIGH TRACKING ACROSS SOUTHEAST CANADA THROUGH EXTREME
NORTHERN NEW ENGLAND. THIS MAY RESULT IN A PERIOD OF WINTRY MIXTURE
WELL TO THE NORTH AND EAST OF I90.
FRIDAY NIGHT THE TRENDS FAVOR A DRY SLOT AS MAIN SURFACE LOW TRACKS
WELL TO OUR WEST AND NORTH AS MAIN UPPER TROUGH AXIS REMAINS
UPSTREAM. SO WE WILL LOWER POPS ACCORDINGLY WITH PORTIONS OF THE
DACKS REMAINING UNDER CHC-SCT POPS. THIS UPPER TROUGH AXIS SLOWLY
TRANSVERSES THE REGION THROUGH THE WEEKEND WITH MAINLY DIURNALLY
DRIVEN SHOWERS WITH THE BEST POTENTIAL ACROSS THE HIGHER TERRAIN.
AS FOR TEMPERATURES THROUGH THE PERIOD...WE HAVE FOLLOWED THE
BLENDED APPROACH OFFERED BY WPC WITH A SLIGHT WARMER TREND DURING
THE OVERNIGHT PERIODS THROUGH THE WEEK DUE TO CLOUD COVER AND WARM
ADVECTION REGIME.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS AT THE PRESENT TIME...HOWEVER...WARM FRONT AND THE
INCREASE IN LOW LEVEL MOISTURE SHOULD RESULT IN A PERIOD OF MVFR
CONDITIONS /MAINLY DUE TO CIGS/ OVERNIGHT AND THROUGH SUNRISE
MONDAY. THERE COULD BE A PERIOD OF MIXED PRECIP /MAINLY SNOW FOR
KGFL/ AS THIS WARM FRONT AND ASSOCIATED NARROW REGION OF PRECIP
LIFTS NORTHWARD. AS THE PASSAGE OF THIS FRONT OCCURS MONDAY
MORNING...MAINLY VFR CONDITIONS WILL OCCUR ONCE AGAIN.
LIGHT AND VARIABLE WINDS OVERNIGHT...BECOMING SOUTHERLY THROUGH
MONDAY AT SPEEDS 10KTS OR LESS.
OUTLOOK...
MON NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA.
TUE-TUE NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
WED: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
WED NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
THU: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
THU NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
FRI: HIGH OPERATIONAL IMPACT. LIKELY SHRA.
&&
.FIRE WEATHER...
TODAY LOOKS MAINLY DRY...EXCEPT NORTHERN AREAS WILL MIGHT SEE A
LITTLE RAINFALL. PARTIAL SUNSHINE AND MINIMUM RH VALUES 35-40
PERCENT CAN BE EXPECTED SOUTH OF I-90...LESS SUNSHINE AND 40-50
PERCENT VALUES NEAR I-90. NORTH OF THE CAPITAL REGION WILL FEATURE
MORE CLOUDS AND THE THREAT OF LIGHT SHOWERS NORTH OF A FRONTAL
BOUNDARY. RH VALUES WILL BE MORE ELEVATED ONLY DROPPING TO THE 50-60
PERCENT RANGE THIS AFTERNOON.
A SOUTH WIND WILL AVERAGE 5-15 MPH FROM I-90 SOUTH...LIGHT AND
VARIABLE FURTHER NORTH NEAR THE FRONT.
THIS FRONT WILL DRIVE OUR WEATHER FOR THE REMAINDER OF THE WEEK. IT
LOOKS MORE UNSETTLED TONIGHT THROUGH THURSDAY WITH PERIODS OF RAIN
EXPECTED AND DAMP CONDITIONS. BY FRIDAY...MOST IF NOT ALL PLACES
SHOULD HAVE SEEN OVER A QUARTER INCH OF RAINFALL. IT LOOKS TO TURN
DRIER BY NEXT WEEKEND.
&&
.HYDROLOGY...
THE FLOOD WARNING FOR THE MOHAWK RIVER AT THE UTICA HARBOR FOR MINOR
FLOODING REMAINS IN EFFECT...BUT COULD BE DROPPED LATER THIS MORNING.
IT NOW LOOKS MAINLY DRY FROM I-90 SOUTH TODAY...WITH SOME LIGHT RAIN
OR SHOWERS NORTH OF I-90 WITH QPF AMOUNTS GENERALLY UNDER A TENTH OF
AN INCH. THIS RAIN WILL HAVE NO ADDED IMPACT ON ALREADY SWOLLEN
STREAMS AND RIVERS.
A STALLED OUT FRONT WILL BECOME MORE ACTIVE AND MOISTURE INCREASES
NEAR IT...AND SEVERAL DISTURBANCES MOVE ALONG IT TONIGHT THROUGH
LATE THURSDAY. MOST OF THE PRECIPITATION WILL FALL AS LIQUID
RAIN...BUT THERE COULD BE SOME SLEET...FREEZING RAIN OR EVEN SNOW IN
OUR NORTHERN AREAS AT NIGHT.
THERE WILL CONTINUE TO BE DIURNAL MELTING OF THE SNOWPACK WITH
TEMPERATURES MOST NIGHTS GETTING COLD ENOUGH SLOW AND EVEN STOP THE
MELT.
THE PRECIPITATION WILL BE LIGHT THROUGH MONDAY NIGHT WITH QPF
AMOUNTS OF A QUARTER INCH OF LESS EXPECTED. HOWEVER MORE SIGNIFICANT
QPF IS EXPECTED TUESDAY AND TUESDAY NIGHT WITH UP TO AN ONE INCH
POSSIBLE. MORE RAINFALL IS EXPECTED WEDNESDAY. THIS RAINFALL COMBINED
WITH RUNOFF FROM SNOWMELT WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. THE METEOROLOGICAL MODEL ENSEMBLE ROVER FORECASTS (MMEFS)
INDICATES THERE IS THE POSSIBILITY OF SOME RIVER POINTS REACHING
ACTION OR PERHAPS EVEN MINOR FLOOD FLOOD STAGE. CONFIDENCE IS NOT
HIGH FOR QPF AMOUNTS AND IS EVEN LOWER FOR THE EXPECTED RUNOFF FROM
SNOWMELT. HAVE ADDED MENTION TO OUR HAZARDOUS WEATHER OUTLOOK.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...IAA/HWJIV
HYDROLOGY...IAA/HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
640 AM EDT MON APR 6 2015
.SYNOPSIS...
HIGH PRESSURE FROM THE SOUTH WILL ATTEMPT TO BRIEFLY
BUILD IN TODAY... SOUTH OF INTERSTATE 90 WHERE IT LOOKS TO BE PARTLY
SUNNY MILD AND DRY. FROM ALBANY NORTHWARD...WHERE A FRONT WILL BE
STALLED...THERE WILL BE MORE IN THE WAY OF CLOUDS AND AN INCREASING
CHANCE OF SHOWERS THE FURTHER NORTH ONE GOES. TONIGHT AS THE FRONT
BEGINS TO SAG SOUTHWARD SHOWERS ARE POSSIBLE EVERYWHERE AND THERE
COULD EVEN BE A LITTLE FREEZING RAIN ACROSS THE ADIRONDACKS.
UNSETTLED WEATHER WILL BE WITH US TUESDAY THROUGH FRIDAY AS A SERIES
OF DISTURBANCES WORK ALONG THE NEARLY STATIONARY FRONT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 500 AM EDT...RADARS CONTINUE TO INDICATE JUST SPOTTY LIGHT
SHOWERS OF SNOW AND RAIN LIFTING NORTH OF THE MOHAWK VALLEY.
TEMPERATURES WERE IN THE LOWER TO MID 30S ALBANY SOUTH...25 TO 30
WELL NORTH OF ALBANY. THESE VALUES MIGHT DROP A POINT OR TWO AT MOST
THROUGH SUNRISE...THEN WILL RISE FAIRLY QUICKLY AFTER SUNRISE.
THE LATEST HRRR INDICATED THIS ACTIVITY MOVING NORTH AND
DISSIPATING. OTHERWISE MANY AREAS MIGHT SEE A DRY DRY WITH SOME
SUNSHINE FROM I-90 SOUTHWARD. THEREFORE OUR FORECAST TODAY IS MORE
OPTIMISTIC THAN THE PREVIOUS ONE AS A BOUNDARY LIFTS JUST NORTH OF I-
90 AND INITIALLY WEAKENS.
WE STILL HAVE SLIGHT POPS ACROSS THE CAPITAL REGION...LOW POPS NORTH
MUCH OF THE DAY. THEREFORE...WE HAVE RAISED TEMPERATURES A LITTLE IN
SOME PLACES COMPARED TO YESTERDAY AS WELL. AREAS WELL SOUTH OF I-90
LOOK TO CRACK 60 OR A LITTLE BETTER. EVEN IN THE CAPITAL
REGION...TEMPERATURES SHOULD GET A NICE BUMP TODAY COMPARED TO
SUNDAY...WITH HIGHS IN THE MID OR UPPER 50S. FURTHER NORTH...WITH
MORE CLOUDS AND BETTER CHANCES FOR LIGHT SHOWERS...WE HELD HIGH
TEMPERATURES FROM THE MID 40S TO LOWER 50S.
THE WIND WILL TURN SOUTHERLY IN MOST AREAS TODAY...5-15 MPH HELPING
TO BRING IN THOSE MILDER TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
NOT A BAD START TO THE WORKWEEK WEATHERWISE...BUT THE WEATHER LOOKS
UNSETTLED FOR THE REMAINDER OF THE SHORT TERM PERIOD.
A DISTURBANCE OVER IOWA WILL HEAD EAST. AT THE SAME TIME...HIGH
PRESSURE OVER WHICH WILL ACTUALLY BEGIN TUGGING THE FRONT SLIGHTLY
SOUTHWARD AS HIGH PRESSURE SOUTHWEST OF JAMES BAY WILL SLIP A BIT
SOUTHWARD...PUSHING THE FRONT BACK TO THE SOUTH OF OUR REGION BY
TUESDAY MORNING. BY THIS TIME...THE AFOREMENTIONED DISTURBANCE WILL
BE IN THE EASTERN OHIO VALLEY. THIS DISTURBANCE WILL INDUCE
ISENTROPIC LIFT INCREASE THE THREAT OF RAIN OR SHOWERS TONIGHT AND
ESPECIALLY ON TUESDAY.
AS COLD SHALLOW AIR FILTERS IN FIRST TO OUR NORTH TONIGHT...THERE IS
A CHANCE OF A LITTLE FREEZING RAIN OVER THE ADIRONDACKS EASTWARD TO
ABOUT LAKE GEORGE. WE WILL MONITOR THIS POSSIBILITY AND ISSUE ANY
HEADLINES IF NECESSARY. LOWS WILL BE FREEZING OR A LITTLE LOWER
NORTHERN AREAS...MID TO UPPER 30S JUST TO THE NORTH OF THE CAPITAL
REGION INCLUDING SOUTHERN VERMONT...40-45 ALBANY SOUTH.
TUESDAY WILL SEE THE BEST CHANCE OF RAIN SLIP SOUTH OF THE CAPITAL
REGION...BUT CHANCES NORTH. IT LOOKS TO BE AN OVERCAST DAY...RAW
NORTH OF ALBANY WITH HIGHS IN THE 40S...TO AROUND 50 IN AND AROUND
ALBANY...LOWER 50S SOUTH.
TUESDAY NIGHT HIGH PRESSURE TO OUR NORTH WILL WEDGE SHALLOW COLD AIR
INTO MUCH OF THE REGION...WITH STILL PLENTY OF LOW LEVEL MOISTURE. WE
KEPT CHANCES FOR PRECIPITATION ACROSS THE ENTIRE AREA. ANY
PRECIPITATION THAT FALLS SHOULD BE IN THE FORM FOR SNOW NORTH OF
ALBANY...RAIN FURTHER SOUTH. HOWEVER...PRECIPITATION ON TUESDAY
NIGHT LOOKS LIGHT. LOWS 25-32 NORTH OF ALBANY...33 TO ABOUT 38
ALBANY SOUTH.
ANOTHER DISTURBANCE LOOKS TO PRODUCE MORE RAIN ON WEDNESDAY. THIS
ONE LOOKS STRONGER...AND WILL PRODUCE STRONGER ISENTROPIC LIFT AS
THE SURFACE BOUNDARY LOOKS TO REMAIN SOUTH OF I84. THERE IS A GOOD
CHANCE OF MORE RAIN THAT DAY. HIGHS WILL ONLY BE IN THE 40S...MAYBE
SOME LOWER 50S NEAR INTERSTATE 84. AS LOW PRESSURE PUSH TO OUR EAST
LATE WEDNESDAY NIGHT...PRECIPITATION MIGHT END AS SOME SNOW SHOWERS
ACROSS ALL AREAS AS LOWS DIP DOWN FROM THE UPPER 20S NORTH TO MID
30S SOUTH.
THE QPF TUESDAY AND TUESDAY NIGHT AND AGAIN WEDNESDAY WILL BE MORE
SIGNIFICANT AND AT THIS TIME IT APPEARS THAT QPF AMOUNTS UP TO AN
ONE INCH ARE POSSIBLE. THIS WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. REFER TO HYDROLOGY SECTION FOR MORE DETAILS. WE WILL
CONTINUE TO MENTION IN OUR HAZARDOUS WEATHER OUTLOOK (HWO).
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN ACTIVE PERIOD OF WEATHER REMAINS IN THE FORECAST AS THE SYNOPTIC
FLOW AMPLIFIES ACROSS THE WESTERN CONUS AS A STRONGER WAVE COMES
ASHORE ACROSS PACIFIC COAST.
PER THE GLOBAL MODEL CONSENSUS...THIS STRONG WAVE MOVES OUT ONTO THE
PLAINS WITH A STRONG LOW LEVEL JET RESPONSE AND GULF OF MEXICO
MOISTURE RETURN FOR MORE CLOUDS AND WET CONDITIONS FOR THE REGION
LATER THURSDAY AND CONTINUING INTO FRIDAY. WE WILL KEEP LIKELY POPS
AT THIS TIME ACROSS THE ENTIRE CWFA. WHILE MOST OF THE
PRECIPITATION WILL FALL AS A LIQUID...WE CONTINUE TO WATCH TRENDS OF
THE SURFACE HIGH TRACKING ACROSS SOUTHEAST CANADA THROUGH EXTREME
NORTHERN NEW ENGLAND. THIS MAY RESULT IN A PERIOD OF WINTRY MIXTURE
WELL TO THE NORTH AND EAST OF I90.
FRIDAY NIGHT THE TRENDS FAVOR A DRY SLOT AS MAIN SURFACE LOW TRACKS
WELL TO OUR WEST AND NORTH AS MAIN UPPER TROUGH AXIS REMAINS
UPSTREAM. SO WE WILL LOWER POPS ACCORDINGLY WITH PORTIONS OF THE
DACKS REMAINING UNDER CHC-SCT POPS. THIS UPPER TROUGH AXIS SLOWLY
TRANSVERSES THE REGION THROUGH THE WEEKEND WITH MAINLY DIURNALLY
DRIVEN SHOWERS WITH THE BEST POTENTIAL ACROSS THE HIGHER TERRAIN.
AS FOR TEMPERATURES THROUGH THE PERIOD...WE HAVE FOLLOWED THE
BLENDED APPROACH OFFERED BY WPC WITH A SLIGHT WARMER TREND DURING
THE OVERNIGHT PERIODS THROUGH THE WEEK DUE TO CLOUD COVER AND WARM
ADVECTION REGIME.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS AT THE PRESENT TIME...HOWEVER...WARM FRONT AND THE
INCREASE IN LOW LEVEL MOISTURE SHOULD RESULT IN A PERIOD OF MVFR
CONDITIONS /MAINLY DUE TO CIGS/ OVERNIGHT AND THROUGH SUNRISE
MONDAY. THERE COULD BE A PERIOD OF MIXED PRECIP /MAINLY SNOW FOR
KGFL/ AS THIS WARM FRONT AND ASSOCIATED NARROW REGION OF PRECIP
LIFTS NORTHWARD. AS THE PASSAGE OF THIS FRONT OCCURS MONDAY
MORNING...MAINLY VFR CONDITIONS WILL OCCUR ONCE AGAIN.
LIGHT AND VARIABLE WINDS OVERNIGHT...BECOMING SOUTHERLY THROUGH
MONDAY AT SPEEDS 10KTS OR LESS.
OUTLOOK...
MON NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA.
TUE-TUE NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
WED: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
WED NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
THU: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
THU NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
FRI: HIGH OPERATIONAL IMPACT. LIKELY SHRA.
&&
.FIRE WEATHER...
TODAY LOOKS MAINLY DRY...EXCEPT NORTHERN AREAS WILL MIGHT SEE A
LITTLE RAINFALL. PARTIAL SUNSHINE AND MINIMUM RH VALUES 35-40
PERCENT CAN BE EXPECTED SOUTH OF I-90...LESS SUNSHINE AND 40-50
PERCENT VALUES NEAR I-90. NORTH OF THE CAPITAL REGION WILL FEATURE
MORE CLOUDS AND THE THREAT OF LIGHT SHOWERS NORTH OF A FRONTAL
BOUNDARY. RH VALUES WILL BE MORE ELEVATED ONLY DROPPING TO THE 50-60
PERCENT RANGE THIS AFTERNOON.
A SOUTH WIND WILL AVERAGE 5-15 MPH FROM I-90 SOUTH...LIGHT AND
VARIABLE FURTHER NORTH NEAR THE FRONT.
THIS FRONT WILL DRIVE OUR WEATHER FOR THE REMAINDER OF THE WEEK. IT
LOOKS MORE UNSETTLED TONIGHT THROUGH THURSDAY WITH PERIODS OF RAIN
EXPECTED AND DAMP CONDITIONS. BY FRIDAY...MOST IF NOT ALL PLACES
SHOULD HAVE SEEN OVER A QUARTER INCH OF RAINFALL. IT LOOKS TO TURN
DRIER BY NEXT WEEKEND.
&&
.HYDROLOGY...
THE FLOOD WARNING FOR THE MOHAWK RIVER AT THE UTICA HARBOR FOR MINOR
FLOODING REMAINS IN EFFECT...BUT COULD BE DROPPED LATER THIS MORNING.
IT NOW LOOKS MAINLY DRY FROM I-90 SOUTH TODAY...WITH SOME LIGHT RAIN
OR SHOWERS NORTH OF I-90 WITH QPF AMOUNTS GENERALLY UNDER A TENTH OF
AN INCH. THIS RAIN WILL HAVE NO ADDED IMPACT ON ALREADY SWOLLEN
STREAMS AND RIVERS.
A STALLED OUT FRONT WILL BECOME MORE ACTIVE AND MOISTURE INCREASES
NEAR IT...AND SEVERAL DISTURBANCES MOVE ALONG IT TONIGHT THROUGH
LATE THURSDAY. MOST OF THE PRECIPITATION WILL FALL AS LIQUID
RAIN...BUT THERE COULD BE SOME SLEET...FREEZING RAIN OR EVEN SNOW IN
OUR NORTHERN AREAS AT NIGHT.
THERE WILL CONTINUE TO BE DIURNAL MELTING OF THE SNOWPACK WITH
TEMPERATURES MOST NIGHTS GETTING COLD ENOUGH SLOW AND EVEN STOP THE
MELT.
THE PRECIPITATION WILL BE LIGHT THROUGH MONDAY NIGHT WITH QPF
AMOUNTS OF A QUARTER INCH OF LESS EXPECTED. HOWEVER MORE SIGNIFICANT
QPF IS EXPECTED TUESDAY AND TUESDAY NIGHT WITH UP TO AN ONE INCH
POSSIBLE. MORE RAINFALL IS EXPECTED WEDNESDAY. THIS RAINFALL COMBINED
WITH RUNOFF FROM SNOWMELT WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. THE METEOROLOGICAL MODEL ENSEMBLE ROVER FORECASTS (MMEFS)
INDICATES THERE IS THE POSSIBILITY OF SOME RIVER POINTS REACHING
ACTION OR PERHAPS EVEN MINOR FLOOD FLOOD STAGE. CONFIDENCE IS NOT
HIGH FOR QPF AMOUNTS AND IS EVEN LOWER FOR THE EXPECTED RUNOFF FROM
SNOWMELT. HAVE ADDED MENTION TO OUR HAZARDOUS WEATHER OUTLOOK.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...IAA/HWJIV
HYDROLOGY...IAA/HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
459 AM EDT MON APR 6 2015
.SYNOPSIS...
HIGH PRESSURE FROM THE SOUTH WILL ATTEMPT TO BRIEFLY
BUILD IN TODAY... SOUTH OF INTERSTATE 90 WHERE IT LOOKS TO BE PARTLY
SUNNY MILD AND DRY. FROM ALBANY NORTHWARD...WHERE A FRONT WILL BE
STALLED...THERE WILL BE MORE IN THE WAY OF CLOUDS AND AN INCREASING
CHANCE OF SHOWERS THE FURTHER NORTH ONE GOES. TONIGHT AS THE FRONT
BEGINS TO SAG SOUTHWARD SHOWERS ARE POSSIBLE EVERYWHERE AND THERE
COULD EVEN BE A LITTLE FREEZING RAIN ACROSS THE ADIRONDACKS.
UNSETTLED WEATHER WILL BE WITH US TUESDAY THROUGH FRIDAY AS A SERIES
OF DISTURBANCES WORK ALONG THE NEARLY STATIONARY FRONT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 500 AM EDT...RADARS CONTINUE TO INDICATE JUST SPOTTY LIGHT
SHOWERS OF SNOW AND RAIN LIFTING NORTH OF THE MOHAWK VALLEY.
TEMPERATURES WERE IN THE LOWER TO MID 30S ALBANY SOUTH...25 TO 30
WELL NORTH OF ALBANY. THESE VALUES MIGHT DROP A POINT OR TWO AT MOST
THROUGH SUNRISE...THEN WILL RISE FAIRLY QUICKLY AFTER SUNRISE.
THE LATEST HRRR INDICATED THIS ACTIVITY MOVING NORTH AND
DISSIPATING. OTHERWISE MANY AREAS MIGHT SEE A DRY DRY WITH SOME
SUNSHINE FROM I-90 SOUTHWARD. THEREFORE OUR FORECAST TODAY IS MORE
OPTIMISTIC THAN THE PREVIOUS ONE AS A BOUNDARY LIFTS JUST NORTH OF I-
90 AND INITIALLY WEAKENS.
WE STILL HAVE SLIGHT POPS ACROSS THE CAPITAL REGION...LOW POPS NORTH
MUCH OF THE DAY. THEREFORE...WE HAVE RAISED TEMPERATURES A LITTLE IN
SOME PLACES COMPARED TO YESTERDAY AS WELL. AREAS WELL SOUTH OF I-90
LOOK TO CRACK 60 OR A LITTLE BETTER. EVEN IN THE CAPITAL
REGION...TEMPERATURES SHOULD GET A NICE BUMP TODAY COMPARED TO
SUNDAY...WITH HIGHS IN THE MID OR UPPER 50S. FURTHER NORTH...WITH
MORE CLOUDS AND BETTER CHANCES FOR LIGHT SHOWERS...WE HELD HIGH
TEMPERATURES FROM THE MID 40S TO LOWER 50S.
THE WIND WILL TURN SOUTHERLY IN MOST AREAS TODAY...5-15 MPH HELPING
TO BRING IN THOSE MILDER TEMPERATURES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
NOT A BAD START TO THE WORKWEEK WEATHERWISE...BUT THE WEATHER LOOKS
UNSETTLED FOR THE REMAINDER OF THE SHORT TERM PERIOD.
A DISTURBANCE OVER IOWA WILL HEAD EAST. AT THE SAME TIME...HIGH
PRESSURE OVER WHICH WILL ACTUALLY BEGIN TUGGING THE FRONT SLIGHTLY
SOUTHWARD AS HIGH PRESSURE SOUTHWEST OF JAMES BAY WILL SLIP A BIT
SOUTHWARD...PUSHING THE FRONT BACK TO THE SOUTH OF OUR REGION BY
TUESDAY MORNING. BY THIS TIME...THE AFOREMENTIONED DISTURBANCE WILL
BE IN THE EASTERN OHIO VALLEY. THIS DISTURBANCE WILL INDUCE
ISENTROPIC LIFT INCREASE THE THREAT OF RAIN OR SHOWERS TONIGHT AND
ESPECIALLY ON TUESDAY.
AS COLD SHALLOW AIR FILTERS IN FIRST TO OUR NORTH TONIGHT...THERE IS
A CHANCE OF A LITTLE FREEZING RAIN OVER THE ADIRONDACKS EASTWARD TO
ABOUT LAKE GEORGE. WE WILL MONITOR THIS POSSIBILITY AND ISSUE ANY
HEADLINES IF NECESSARY. LOWS WILL BE FREEZING OR A LITTLE LOWER
NORTHERN AREAS...MID TO UPPER 30S JUST TO THE NORTH OF THE CAPITAL
REGION INCLUDING SOUTHERN VERMONT...40-45 ALBANY SOUTH.
TUESDAY WILL SEE THE BEST CHANCE OF RAIN SLIP SOUTH OF THE CAPITAL
REGION...BUT CHANCES NORTH. IT LOOKS TO BE AN OVERCAST DAY...RAW
NORTH OF ALBANY WITH HIGHS IN THE 40S...TO AROUND 50 IN AND AROUND
ALBANY...LOWER 50S SOUTH.
TUESDAY NIGHT HIGH PRESSURE TO OUR NORTH WILL WEDGE SHALLOW COLD AIR
INTO MUCH OF THE REGION...WITH STILL PLENTY OF LOW LEVEL MOISTURE. WE
KEPT CHANCES FOR PRECIPITATION ACROSS THE ENTIRE AREA. ANY
PRECIPITATION THAT FALLS SHOULD BE IN THE FORM FOR SNOW NORTH OF
ALBANY...RAIN FURTHER SOUTH. HOWEVER...PRECIPITATION ON TUESDAY
NIGHT LOOKS LIGHT. LOWS 25-32 NORTH OF ALBANY...33 TO ABOUT 38
ALBANY SOUTH.
ANOTHER DISTURBANCE LOOKS TO PRODUCE MORE RAIN ON WEDNESDAY. THIS
ONE LOOKS STRONGER...AND WILL PRODUCE STRONGER ISENTROPIC LIFT AS
THE SURFACE BOUNDARY LOOKS TO REMAIN SOUTH OF I84. THERE IS A GOOD
CHANCE OF MORE RAIN THAT DAY. HIGHS WILL ONLY BE IN THE 40S...MAYBE
SOME LOWER 50S NEAR INTERSTATE 84. AS LOW PRESSURE PUSH TO OUR EAST
LATE WEDNESDAY NIGHT...PRECIPITATION MIGHT END AS SOME SNOW SHOWERS
ACROSS ALL AREAS AS LOWS DIP DOWN FROM THE UPPER 20S NORTH TO MID
30S SOUTH.
THE QPF TUESDAY AND TUESDAY NIGHT AND AGAIN WEDNESDAY WILL BE MORE
SIGNIFICANT AND AT THIS TIME IT APPEARS THAT QPF AMOUNTS UP TO AN
ONE INCH ARE POSSIBLE. THIS WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. REFER TO HYDROLOGY SECTION FOR MORE DETAILS. WE WILL
CONTINUE TO MENTION IN OUR HAZARDOUS WEATHER OUTLOOK (HWO).
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AN ACTIVE PERIOD OF WEATHER REMAINS IN THE FORECAST AS THE SYNOPTIC
FLOW AMPLIFIES ACROSS THE WESTERN CONUS AS A STRONGER WAVE COMES
ASHORE ACROSS PACIFIC COAST.
PER THE GLOBAL MODEL CONSENSUS...THIS STRONG WAVE MOVES OUT ONTO THE
PLAINS WITH A STRONG LOW LEVEL JET RESPONSE AND GULF OF MEXICO
MOISTURE RETURN FOR MORE CLOUDS AND WET CONDITIONS FOR THE REGION
LATER THURSDAY AND CONTINUING INTO FRIDAY. WE WILL KEEP LIKELY POPS
AT THIS TIME ACROSS THE ENTIRE CWFA. WHILE MOST OF THE
PRECIPITATION WILL FALL AS A LIQUID...WE CONTINUE TO WATCH TRENDS OF
THE SURFACE HIGH TRACKING ACROSS SOUTHEAST CANADA THROUGH EXTREME
NORTHERN NEW ENGLAND. THIS MAY RESULT IN A PERIOD OF WINTRY MIXTURE
WELL TO THE NORTH AND EAST OF I90.
FRIDAY NIGHT THE TRENDS FAVOR A DRY SLOT AS MAIN SURFACE LOW TRACKS
WELL TO OUR WEST AND NORTH AS MAIN UPPER TROUGH AXIS REMAINS
UPSTREAM. SO WE WILL LOWER POPS ACCORDINGLY WITH PORTIONS OF THE
DACKS REMAINING UNDER CHC-SCT POPS. THIS UPPER TROUGH AXIS SLOWLY
TRANSVERSES THE REGION THROUGH THE WEEKEND WITH MAINLY DIURNALLY
DRIVEN SHOWERS WITH THE BEST POTENTIAL ACROSS THE HIGHER TERRAIN.
AS FOR TEMPERATURES THROUGH THE PERIOD...WE HAVE FOLLOWED THE
BLENDED APPROACH OFFERED BY WPC WITH A SLIGHT WARMER TREND DURING
THE OVERNIGHT PERIODS THROUGH THE WEEK DUE TO CLOUD COVER AND WARM
ADVECTION REGIME.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS AT THE PRESENT TIME...HOWEVER...WARM FRONT AND THE
INCREASE IN LOW LEVEL MOISTURE SHOULD RESULT IN A PERIOD OF MVFR
CONDITIONS /MAINLY DUE TO CIGS/ OVERNIGHT AND THROUGH SUNRISE
MONDAY. THERE COULD BE A PERIOD OF MIXED PRECIP /MAINLY SNOW FOR
KGFL/ AS THIS WARM FRONT AND ASSOCIATED NARROW REGION OF PRECIP
LIFTS NORTHWARD. AS THE PASSAGE OF THIS FRONT OCCURS MONDAY
MORNING...MAINLY VFR CONDITIONS WILL OCCUR ONCE AGAIN.
LIGHT AND VARIABLE WINDS OVERNIGHT...BECOMING SOUTHERLY THROUGH
MONDAY AT SPEEDS 10KTS OR LESS.
OUTLOOK...
MON NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA.
TUE-TUE NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
WED: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
WED NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
THU: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
THU NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
FRI: HIGH OPERATIONAL IMPACT. LIKELY SHRA.
&&
.FIRE WEATHER...
TODAY LOOKS MAINLY DRY...EXCEPT NORTHERN AREAS WILL MIGHT SEE A
LITTLE RAINFALL. PARTIAL SUNSHINE AND MINIMUM RH VALUES 35-40
PERCENT CAN BE EXPECTED SOUTH OF I-90...LESS SUNSHINE AND 40-50
PERCENT VALUES NEAR I-90. NORTH OF THE CAPITAL REGION WILL FEATURE
MORE CLOUDS AND THE THREAT OF LIGHT SHOWERS NORTH OF A FRONTAL
BOUNDARY. RH VALUES WILL BE MORE ELEVATED ONLY DROPPING TO THE 50-60
PERCENT RANGE THIS AFTERNOON.
A SOUTH WIND WILL AVERAGE 5-15 MPH FROM I-90 SOUTH...LIGHT AND
VARIABLE FURTHER NORTH NEAR THE FRONT.
THIS FRONT WILL DRIVE OUR WEATHER FOR THE REMAINDER OF THE WEEK. IT
LOOKS MORE UNSETTLED TONIGHT THROUGH THURSDAY WITH PERIODS OF RAIN
EXPECTED AND DAMP CONDITIONS. BY FRIDAY...MOST IF NOT ALL PLACES
SHOULD HAVE SEEN OVER A QUARTER INCH OF RAINFALL. IT LOOKS TO TURN
DRIER BY NEXT WEEKEND.
&&
.HYDROLOGY...
THE FLOOD WARNING FOR THE MOHAWK RIVER AT THE UTICA HARBOR FOR MINOR
FLOODING REMAINS IN EFFECT...BUT COULD BE DROPPED LATER THIS MORNING.
IT NOW LOOKS MAINLY DRY FROM I-90 SOUTH TODAY...WITH SOME LIGHT RAIN
OR SHOWERS NORTH OF I-90 WITH QPF AMOUNTS GENERALLY UNDER A TENTH OF
AN INCH. THIS RAIN WILL HAVE NO ADDED IMPACT ON ALREADY SWOLLEN
STREAMS AND RIVERS.
A STALLED OUT FRONT WILL BECOME MORE ACTIVE AND MOISTURE INCREASES
NEAR IT...AND SEVERAL DISTURBANCES MOVE ALONG IT TONIGHT THROUGH
LATE THURSDAY. MOST OF THE PRECIPITATION WILL FALL AS LIQUID
RAIN...BUT THERE COULD BE SOME SLEET...FREEZING RAIN OR EVEN SNOW IN
OUR NORTHERN AREAS AT NIGHT.
THERE WILL CONTINUE TO BE DIURNAL MELTING OF THE SNOWPACK WITH
TEMPERATURES MOST NIGHTS GETTING COLD ENOUGH SLOW AND EVEN STOP THE
MELT.
THE PRECIPITATION WILL BE LIGHT THROUGH MONDAY NIGHT WITH QPF
AMOUNTS OF A QUARTER INCH OF LESS EXPECTED. HOWEVER MORE SIGNIFICANT
QPF IS EXPECTED TUESDAY AND TUESDAY NIGHT WITH UP TO AN ONE INCH
POSSIBLE. MORE RAINFALL IS EXPECTED WEDNESDAY. THIS RAINFALL COMBINED
WITH RUNOFF FROM SNOWMELT WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. THE METEOROLOGICAL MODEL ENSEMBLE ROVER FORECASTS (MMEFS)
INDICATES THERE IS THE POSSIBILITY OF SOME RIVER POINTS REACHING
ACTION OR PERHAPS EVEN MINOR FLOOD FLOOD STAGE. CONFIDENCE IS NOT
HIGH FOR QPF AMOUNTS AND IS EVEN LOWER FOR THE EXPECTED RUNOFF FROM
SNOWMELT. HAVE ADDED MENTION TO OUR HAZARDOUS WEATHER OUTLOOK.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...HWJIV
HYDROLOGY...IAA/HWJIV
AREA FORECAST DISCUSSION
NWS ALBANY NY
102 AM EDT MON APR 6 2015
.SYNOPSIS...
UNSETTLED WEATHER IS EXPECTED THIS WEEK...AS AN EAST WEST FRONTAL
BOUNDARY FIRST MOVES NORTH TO THE I90 CORRIDOR MONDAY...THEN
SHIFTS SLOWLY SOUTH THROUGH THE MID ATLANTIC REGION MUCH OF THE
WEEK BEFORE SURGING NORTHWARD LATE IN THE WEEK. IT WILL PROVIDE
THE FOCUS FOR PRECIPITATION WHICH WILL BE MAINLY PERIODS OF RAIN.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/... RADARS INDICATED SPOTTY
SHOWERS OF SNOW AND RAIN WORKING JUST TO THE SOUTH OF I-
09...ATTEMPTING TO MOVE NORTH. THE LATEST HRRR INDICATED THIS
ACTIVITY SHOULD MOVE A LITTLE NORTH INTO THE IMMEDIATE CAPITAL
REGION...BUT QPF WILL BE LIGHT. ANY SNOWFALL ASSOCIATED WITH THIS
FEATURE SHOULD BE LIGHT...NO MORE THAN A COATING IN THE
VALLEYS...MAYBE AN INCH OVER THE HIGHER TERRAIN OF MAINLY THE
CATSKILLS.
TEMPERATURES WERE GENERALLY A LITTLE BELOW FREEZING NORTH AND WEST
OF ALBANY...LOWER TO MID 30S FURTHER SOUTH...EXCEPT AROUND 40 NEAR
POUGHKEEPSIE. OVERNIGHT LOWS LOOK REASONABLE AND WERE LEFT ALONE.
LOOK FOR LOWS IN THE 20S NORTH OF ALBANY...30-35 ALBANY SOUTH.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
THE BOUNDARY WILL LIFT NORTHWARD MONDAY AS A WAVE OF LOW PRESSURE
MOVES EASTWARD ALONG THE BOUNDARY. THE BOUNDARY WILL NOT EXPECTED
TO MOVE TO THE NORTH OF OUR FORECAST AREA BUT IT IS EXPECTED THAT
MUCH OF THE FORECAST AREA WILL MAKE IT INTO THE MILDER AIRMASS.
HIGHS WILL BE IN THE 50S TO NEAR 60S TO THE SOUTH OF THE BOUNDARY
AND IN THE 30S TO 40S NORTH OF THE BOUNDARY.
THE CHANCES FOR PRECIPITATION WILL SHIFT NORTHWARD WITH THE
BOUNDARY AND WILL BE GREATEST ACROSS THE NORTHERN MOST PORTION OF
THE FORECAST AREA AS THE LOW APPROACHES. INITIALLY WILL BE COLD
ENOUGH SNOW THEN CHANGING TO RAIN AS TEMPERATURES WARM ALOFT AND
AT THE SURFACE. AGAIN QPF AMOUNTS WILL BE VERY LIGHT.
AS THE WAVE OF LOW PRESSURE CROSSES THE REGION AND MOVES OFF TO
OUR EAST THE BOUNDARY WILL SHIFT BACK SOUTHWARD. MORE WIDESPREAD
CHANCES FOR RAIN WILL OCCUR AS THIS OCCUR HOWEVER QPF AMOUNTS ARE
STILL EXPECTED TO BY LIGHT.
MORE SIGNIFICANT PRECIPITATION IS EXPECTED FOR TUESDAY AND
TUESDAY NIGHT AS A STRONGER WAVE OF LOW PRESSURE MOVES EASTWARD
ALONG THE BOUNDARY. IN ADDITION...STRENGTHENING HIGH PRESSURE
WILL BUILD INTO AND MOVE ACROSS EASTERN CANADA. THE HIGH WILL
SURPRISE THE BOUNDARY AND LOW FARTHER TO THE SOUTH. THE LOW IS
EXPECTED TO MOVE OFF THE DELMARVA COAST EARLY WEDNESDAY MORNING.
RAIN IS EXPECTED HOWEVER THE GUIDANCE INDICATES THAT COLDER AIR
WILL DRAIN IN AT LOW LEVELS THANKS TO HIGH TO THE NORTH. IT MAY
GET COLD ENOUGH TO RESULT IN A WINTRY MIX OF PRECIPITATION LATE
TUESDAY NIGHT ACROSS THE WESTERN ADIRONDACKS...LAKE GEORGE
SARATOGA REGION AND SOUTHERN VERMONT. WILL KEEP MENTION IN OUR
HAZARDOUS WEATHER OUTLOOK.
THE QPF TUESDAY AND TUESDAY NIGHT WILL BE MORE SIGNIFICANT AND AT
THIS TIME IT APPEARS THAT QPF AMOUNTS UP TO AN ONE INCH ARE
POSSIBLE. THIS WOULD LEAD TO RISES ON AREA RIVERS AND STREAMS.
REFER TO HYDROLOGY SECTION FOR MORE DETAILS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
THE PATTERN WILL BE QUITE UNSETTLED WITH PLENTY OF PRECIPITATION TO
QUASH ANY REMAINING TALK OF A DROUGHT. WHILE WE HAVE CHANCE POPS
FOR MOST OF THE PERIOD UP UNTIL THE END...FRIDAY AND FRIDAY NIGHT
LOOK TO BE POTENTIALLY QUITE WET...WITH ENOUGH MILD AIR IN PLACE SO
THAT ONLY THE HIGHEST ELEVATIONS MAY SEE A MIX WITH SNOW. WE ARE
GOING WITH LIKELY POPS FOR THIS PORTION OF THE EXTENDED DESPITE
CONTINUED UNCERTAINTY AS DISCUSSED FURTHER BELOW.
WEDNESDAY THROUGH THURSDAY...WEAK BOUNDARIES OR SURFACE FRONTS WILL
PLAGUE THE FORECAST AREA WITH LOTS OF CLOUDS AND SHOWERS...ALBEIT
MAINLY ON THE LIGHT SIDE. LOW PRESSURE DEVELOPING OFF THE ROCKY
MOUNTAIN WEST WILL BE WHAT COULD PROVIDE US WITH A GOOD SOAKING
TOWARD WEEK/S END AS IT TRACKS ACROSS THE LOWER GREAT LAKES. THE
ONLY PROBLEM IS THAT GREAT UNCERTAINTY INCREASES TOWARDS THIS TIME
AS TO THE DEGREE OF INTENSIFICATION AND THE TRACK OF THIS SYSTEM.
MODELS STILL DISAGREE.
WARMTH BUILDS THROUGH THE PERIOD TO INCREASING HIGH TEMPERATURES
EACH DAY. WEDNESDAY/S HIGHS WILL RANGE FROM THE UPPER 30S IN THE
ADIRONDACKS...GREENS AND NORTHERN CATSKILLS HIGH PEAKS...TO
AROUND 50 DEGREES IN THE MID HUDSON VALLEY. HIGHS SUNDAY WILL
RANGE FROM AROUND 50 DEGREES IN THE WESTERN ADIRONDACKS...TO
AROUND 60 ACROSS THE MID HUDSON VALLEY. 20S AND 30S WILL BE THE
GENERAL RULE FOR LOWS...ALTHOUGH FRIDAY NIGHT SHOULD STAY AT LEAST
JUST ABOVE FREEZING IN ALMOST ALL SPOTS.
&&
.AVIATION /05Z MONDAY THROUGH FRIDAY/...
MAINLY VFR FLYING CONDITIONS WILL PREVAIL THROUGHOUT THE TAF PERIOD
WITH SOME BRIEF PERIODS OF MVFR THIS EVENING AND TONIGHT ASSOCIATED
WITH WIDELY SCATTERED AND LIGHT RAIN/SNOW SHOWERS.
THIS AFTERNOON...DRY LOW-LEVELS SHOULD INHIBIT MUCH IN THE WAY OF
SHOWER ACTIVITY AT THE TAF SITES THROUGH 21-22Z. THESE SHOWERS ARE
ASSOCIATED WITH A FRONTAL BOUNDARY THAT WILL SLOWLY BE DRIFTING
NORTHWARD ACROSS THE REGION TONIGHT. HAVE INTRODUCED VCSH AT ALL THE
TAF SITES EXCEPT KGFL AROUND 21-22Z FOR WIDELY SCATTERED RAIN
SHOWERS...PERHAPS MIXED IN WITH A FEW WET SNOWFLAKES AT KPSF
ESPECIALLY LATER THIS EVENING. ANY PRECIPITATION WILL BE LIGHT IN
NATURE ALTHOUGH FLYING CONDITIONS MAY BRIEFLY LOWER TO MVFR AT KPOU
AND KPSF.
WINDS WILL BE OUT OF THE WEST/SOUTHWEST GENERALLY AROUND 8-14
KNOTS...WITH SOME GUSTS OCCASIONALLY UP TO 25 KNOTS AT KGFL...KALB
AND KPSF. WINDS WILL RAPIDLY SUBSIDE BY 00Z AS BOUNDARY LAYER MIXING
IS SUPPRESSED.
TONIGHT INTO MONDAY...WIDELY SCATTERED SHOWERS WILL LINGER ACROSS
THE REGION AS THE FRONTAL BOUNDARY LIFTS NORTH. HAVE GONE WITH A
TEMPO GROUP BETWEEN 00Z-03Z FOR MVFR FLYING CONDITIONS AT KPOU
ASSOCIATED WITH RAIN SHOWERS.
WITH GRADUALLY MOISTENING LOW-LEVELS AND BETTER FORCING AS THE
BOUNDARY MOVES ACROSS THE REGION...THERE MAY BE A PERIOD OF MORE
FOCUSED PRECIPITATION...AGAIN LIGHT IN NATURE...BETWEEN 06-12Z AND
HAVE INDICATED PROB30 GROUPS FOR A PERIOD OF POSSIBLE MVFR RAIN/SNOW
SHOWERS AT KALB AND PRIMARILY LIGHT SNOW AT KPSF. ANY SNOW
ACCUMULATIONS ARE EXPECTED TO BE LIGHT IN NATURE...RANGING FROM A
COATING TO A COUPLE OF TENTHS. ANY LINGERING SHOWERS ARE EXPECTED TO
DISSIPATE AFTER 12Z WITH SOME BREAKS IN CLOUD COVER AT KPOU...WITH
OVERCAST SKIES EXPECTED AT THE REST OF THE TAF SITES.
WINDS WILL BECOME LIGHT AND VARIABLE TONIGHT LESS THAN 5 KNOTS AND
BECOME SOUTHERLY MONDAY 5-10 KNOTS.
OUTLOOK...
MON NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF RA.
TUE-TUE NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA.
WED: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
WED NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
THU: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
THU NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
FRI: HIGH OPERATIONAL IMPACT. LIKELY SHRA.
&&
.FIRE WEATHER...
UNSETTLED WEATHER EXPECTED THIS WEEK AS A FRONTAL BOUNDARY
REMAINS IN THE VICINITY OF THE REGION PROVIDING FOCUS FOR
PRECIPITATION WHICH WILL COME MAINLY IN THE FORM OF RAIN.
&&
.HYDROLOGY...
THE FLOOD WARNING FOR THE MOHAWK RIVER AT THE UTICA HARBOR FOR
MINOR FLOODING REMAINS IN EFFECT.
WET UNSETTLED WEATHER EXPECTED THIS WEEK. ROUNDS/PERIODS OF
PRECIPITATION WILL OCCUR THIS WEEK AS NEARLY STATIONARY BOUNDARY
REMAINS IN THE VICINITY OF THE REGION PROVIDING FOCUS FOR THE
PRECIPITATION WHICH WILL COME MAINLY IN THE FORM OF RAIN.
THERE WILL BE DIURNAL MELTING OF THE SNOWPACK WITH TEMPERATURES
MOST NIGHTS GETTING COLD ENOUGH SLOW AND EVEN STOP THE MELT. AN
EXCEPTION WILL BE MONDAY NIGHT WITH TEMPERATURES FORECAST TO ONLY
DROP INTO THE UPPER 30S TO MID 40S.
THE PRECIPITATION WILL BE LIGHT THROUGH MONDAY NIGHT WITH QPF
AMOUNTS OF A QUARTER INCH OF LESS EXPECTED. HOWEVER MORE SIGNIFICANT
QPF IS EXPECTED TUESDAY AND TUESDAY NIGHT WITH UP TO AN ONE INCH
POSSIBLE. MORE RAINFALL IS EXPECTED WEDNESDAY. THIS RAINFALL COMBINED
WITH RUNOFF FROM SNOWMELT WOULD LEAD TO RISES ON AREA RIVERS AND
STREAMS. THE METEOROLOGICAL MODEL ENSEMBLE ROVER FORECASTS (MMEFS)
INDICATES THERE IS THE POSSIBILITY OF SOME RIVER POINTS REACHING
ACTION OR EVEN MINOR FLOOD FLOOD STAGE. CONFIDENCE IS NOT HIGH FOR
QPF AMOUNTS AND IS EVEN LOWER FOR THE EXPECTED RUNOFF FROM SNOWMELT.
HAVE ADDED MENTION TO OUR HAZARDOUS WEATHER OUTLOOK.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$ SYNOPSIS...IAA/SNYDER
NEAR TERM...IAA/SNYDER/HWJIV
SHORT TERM...IAA
LONG TERM...ELH
AVIATION...IRL
FIRE WEATHER...IAA
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
948 AM EDT MON APR 6 2015
.UPDATE...
A WEAK FRONTAL BOUNDARY CONTINUES TO STRETCH ACROSS NORTHERN
FLORIDA PRODUCING A BROKEN TO OVERCAST CLOUD DECK. A FEW SPOTTY
SHOWERS WERE ON RADAR EARLY THIS MORNING JUST NORTH OF OUR
CWA...BUT CONDITIONS ARE CLEARING OUT NOW. EASTERLY WINDS WILL
CONTINUE TODAY AS HIGH PRESSURE OVER THE WESTERN ATLANTIC RIDGES
OVER THE FLORIDA PENINSULA. SIMILIAR TO YESTERDAY...THE EAST COAST
SEA BREEZE WILL SETUP EARLY AND PROPAGATE WESTWARD. SHOWERS ARE
EXPECTED TO DEVELOP OVER THE INLAND AREAS BY EARLY AFTERNOON AND
MOVE TOWARD THE WEST COAST OF FLORIDA. WITH SUFFICIENT DAYTIME
HEATING...THE WEST COAST SEA BREEZE WILL SETUP AROUND 20Z AND MOVE
SLIGHTLY INLAND. THE LATEST HIGH RESOLUTION GUIDANCE HAS THE
STRONGEST SHOWERS AND POSSIBLE STORMS ALONG THE SEA BREEZE
CONVERGENCE LINE FROM CITRUS COUNTY SOUTHWARD TO MANATEE COUNTY
AROUND 00Z. TEMPERATURES ARE WARMING UP NICELY THIS MORNING AND
ARE ALREADY IN THE LOW TO MID 70S. HIGHS ARE EXPECTED TO REACH THE
UPPER 80S FOR MUCH OF THE REGION AND POSSIBLY 90 ALONG THE INLAND
AREAS. BASED ON CURRENT RADAR AND HRRR GUIDANCE...WILL TRIM DOWN
THE POPS THROUGH 18Z...THEN BRING IN 30-40 PERCENT OF SHOWERS AND
STORMS BETWEEN 18Z TO 00Z. WILL UPDATE ZONES TO REFLECT CHANGES.
&&
.AVIATION...
OVERALL VFR CONDITIONS EXPECTED THROUGH THE DAY. A SEA BREEZE IS
EXPECTED TO DEVELOP LATER TODAY...CREATING THE POTENTIAL FOR
AFTERNOON SHOWERS AND STORMS FOR MOST TAF LOCATIONS AFTER 19Z.
WILL COVER THIS PERIOD WITH VCSH AND ADD TEMPO LINES BASED ON
RADAR COVERAGE DURING THE AFTERNOON HOURS. SHOWER COVERAGE IS
EXPECTED TO DECREASE AFTER SUNSET.
&&
.MARINE...
HIGH PRESSURE IN THE WESTERN ATLANTIC WILL KEEP AN OVERALL
EASTERLY WIND FLOW EXCEPT CLOSER TO THE COAST WHERE THE WINDS WILL
TURN ONSHORE WITH AN AFTERNOON SEA BREEZE. WINDS WILL REMAIN LESS
THAN 15 KNOTS AND SEAS LESS THAN 2 FEET THROUGHOUT THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 84 69 85 69 / 30 20 30 10
FMY 88 68 87 68 / 20 10 20 10
GIF 86 68 87 68 / 40 20 40 20
SRQ 84 68 84 68 / 10 10 10 10
BKV 86 65 86 63 / 40 30 40 20
SPG 84 71 85 72 / 20 20 20 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE...74/WYNN
DECISION SUPPORT...05/CARLISLE
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
313 AM EDT MON APR 6 2015
...ABOVE NORMAL TEMPERATURES THROUGH MUCH OF THE WEEK WITH
SCATTERED MAINLY AFTERNOON SHOWERS AND THUNDERSTORMS...
.SHORT TERM...TODAY THROUGH TUESDAY...
THIS MORNING...NAM12 AND HRRR MODELS BEST REPRESENTED STRENGTH OF
INVERTED COASTAL TROUGH OFFSHORE OF THE FIRST COAST WITH THE BULK
OF COASTAL SHOWER ACTIVITY WELL SOUTH NEAR CAPE CANAVERAL.
ABUNDANT MID AND HIGH CLOUDS PASSED OVERHEAD DOWNSTREAM OF A MID
LEVEL SHORT WAVE TROUGH TREKKING EASTWARD ACROSS THE CENTRAL GULF
COAST REGION. TEMPS WERE MILD ACROSS THE LOCAL AREA EARLY THIS
MORNING UNDER MOSTLY CLOUDY SKIES AND RANGED FROM THE LOW TO MID
60S. ENE FLOW WAS GRADUALLY DIMINISHING IN INTENSITY AS THE
COASTAL TROUGH CONTINUES TO WEAKEN AND MORPH INTO A PSEUDO- WARM
FRONT LIFTING NORTHWARD UP THE FL PENINSULA.
TODAY...SHORT TERM MODEL GUIDANCE INCLUDING THE HRRR...NAM12 AND
SREF ADVERTISED LOW CHANCES OF COASTAL SHOWERS THROUGH THE MORNING
HOURS AS THE TROUGH BREAKS DOWN AND LIFTS NORTHWARD UP THE FL
ATLANTIC COAST. IN THE UPPER LEVELS SHORT WAVE TROUGH ENERGY WILL
INCREASE FROM THE WEST WHICH WILL COMBINE WITH THE SHALLOW FORCING
ALONG THE LIFTING FRONTAL ZONE TO GENERATE A CHANCE OF SCATTERED
SHOWERS BREAKING OUT BOTH ALONG THE ATLANTIC COAST AND OVER INLAND
SE GA THROUGH THE LATE MORNING HOURS. ENOUGH INSOLATION SHOULD
BREAK OUT TO SUPPORT THE POTENTIAL FOR ISOLATED THUNDERSTORM
DEVELOPMENT INTO THE EARLY AFTERNOON AS THE EAST COAST SEA BREEZE
TRACKS INLAND AND CONVERGES ALONG AND WEST OF THE I-75 CORRIDOR
INTO THE LATE AFTN AND EARLY EVENING HOURS. PASSING UPPER LEVEL
SHORT WAVE TROUGH ENERGY APPEARED WEAK IN THE MODEL GUIDANCE
HOWEVER COLD 500 MB TEMPS AROUND -12 TO -14 COULD SUPPORT A FEW
STRONGER TSTORMS ACROSS SE GA IN THE AFTN CAPABLE OF PRODUCING
FREQUENT LIGHTNING AND SMALL HAIL. HIGH TEMPS WILL RISE TO NEAR
CLIMO VALUES ALONG AND EAST OF THE ST JOHNS RIVER BASIN TODAY TO
THE LOWER 80S INLAND TOWARD I-75.
TONIGHT...PRECIP WILL FADE IN COVERAGE AND INTENSITY EARLY THIS EVENING
ALONG THE I-75 CORRIDOR WITH DRY CONDITIONS EXPECTED BY MIDNIGHT WITH
LINGERING DEBRIS CLOUDINESS. AREAS OF FOG DEVELOPMENT POSSIBLE ESPECIALLY
OVER NE FL LATE AS LOW LEVEL RIDGE AXIS POTIONS ACROSS THE AREA ESPECIALLY
WHERE RAINFALL OCCURRED MON AFTERNOON. MIN TEMPS WILL BE MILD AND MUGGY
IN THE LOW/MID 60S INLAND TO UPPER 60S COAST.
TUE...THE SURFACE TROUGH WILL LIFT NORTH OF THE ALTAMAHA RIVER BASIN
TRIALING A LINGERING MOISTURE PLUME OVER THE LOCAL AREA. IN THE UPPER
LEVELS A SHORT WAVE TROUGH IS EXPECTED TO CROSS THE AREA FROM THE WNW
IN THE AFTN AND THIS FEATURE COMBINED WITH HIGH MOISTURE AND SEA BREEZE
INTERACTIONS SUPPORTED A CHANCE OF DIURNALLY DRIVEN AFTN/EVENING SHOWERS/TSTORMS
FOCUSED BETWEEN ST JOHNS RIVER BASIN AND THE I-75 CORRIDOR. HIGHS
WILL RISE INTO THE MID 80S INLAND TO UPPER 70S COAST
WEDNESDAY...UPPER RIDGE WILL BUILD OVER THE AREA WITH WARMING
TEMPERATURES. SCATTERED PM STORMS EXPECTED OVER THE INTERIOR AS
SEABREEZE COLLIDE. HIGH TEMPERATURES WILL BE NEAR 80 DEGREES AT THE
COAST TO THE UPPER 80S INLAND.
.LONG TERM...THURSDAY THROUGH SUNDAY...RIDGE BUILDS STRONGER ACROSS
THE AREA ON THURSDAY. SUBSIDENCE WILL PRODUCE WARMER AND DRIER MID
LEVELS RESULTING IN ONLY ISOLATED STORMS OVER THE INTERIOR WITH THE
LATE AFTERNOON/EVENING SEABREEZE COLLISION. UPPER RIDGE WILL WEAKEN
FRIDAY AS UPPER TROUGH MOVES TOWARDS THE EAST COAST. RAIN CHANCES
WILL INCREASE BY EVENING ESPECIALLY OVER SE GA AS A COLD FRONT
APPROACHES FROM THE NW. ORGANIZED CONVECTION WILL PERSIST NEXT
WEEKEND AS UPPER TROUGH AND COLD FRONT MOVE INTO THE AREA.
TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE PERIOD. POPS WILL BE
AT OR BELOW AVERAGE THURSDAY AND THEN AT OR ABOVE AVERAGE FRI-SUN.
&&
.AVIATION...
MVFR CIGS ADVERTISED BY 12Z AS COASTAL SHOWERS CREEP NORTHWARD UP
THE FLORIDA ATLANTIC COAST UNDER VEERING NE TO E FLOW. AS SHOWER
ACTIVITY SHIFTS INLAND THROUGH THE DAY...CIGS WILL RISE TRAILING
THE EAST COAST BREEZE ACROSS COASTAL AREAS AS BREEZY SE FLOW
DEVELOPS. BEST CHANCES OF AFTN THUNDERSTORMS AT GNV HOWEVER WITH
LOW PROBABILITIES OF THUNDER FORECAST CONTINUED WITH VCSH AT THIS
TIME BEGINNING AROUND 18Z.
.MARINE...
A COASTAL TROUGH WILL WEAKEN AND LIFT NORTH OF THE WATERS TODAY.
NE WINDS RELAXED OVERNIGHT WITH SPEEDS DROPPING BELOW ADVISORY
LEVELS AND SEAS RELAXED BELOW 6 FT AT BUOY 41008. DROPPED THE
ADVISORY FOR THE OFFSHORE WATERS AND REPLACED WITH AN EXERCISE
CAUTION HEADLINE FOR TODAY AS WINDS WILL CONTINUE VEER SE.
SURFACE HIGH PRESSURE WILL BUILD NORTHEAST OF THE AREA TUESDAY
THEN EAST OF THE LOCAL WATERS WEDNESDAY THROUGH FRIDAY. SOUTHERLY
FLOW WILL PREVAIL THIS AFTERNOON THROUGH THE END OF THE WEEK.
RIP CURRENTS: MODERATE RISK OF RIP CURRENTS TODAY. LOW TO
MODERATE RISK TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 80 65 84 64 / 40 10 40 10
SSI 72 65 74 64 / 40 10 20 0
JAX 79 67 84 65 / 40 10 30 0
SGJ 76 67 78 64 / 30 10 20 0
GNV 83 67 84 63 / 50 20 30 20
OCF 85 67 85 64 / 40 20 40 30
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
ENYEDI/ZIBURA
AREA FORECAST DISCUSSION
NWS POCATELLO ID
245 AM MDT MON APR 6 2015
.SHORT TERM...TODAY THROUGH THURSDAY MORNING. WV IMAGERY THIS
MORNING SHOWS UPPER LOW SPINNING OFF OR COAST AND TRACKING TOWARDS
THE SOUTHEAST. RADAR IS PICKING UP SOME CONVECTION IN A LINE FROM
MOUNTAIN HOME TO MCCALL ALONG A SHORTWAVE LIFTING THROUGH THE AREA.
WE ARE ALSO SEEING SOME BANDED RADAR ECHOES FORMING ACROSS THE
SOUTHEASTERN AND SOUTH CENTRAL HIGHLANDS ALONG A LINE OF 700MB
FRONTOGENESIS. MODELS ARE CONTINUING TO PUSH FOR MORNING PRECIP
ALONG THIS MESOSCALE BAND. THE HRRR DRIVES MUCH OF THE ENERGY FROM
THE SHORTWAVE WELL OFF TO THE NORTH BY 12Z...BUT CONTINUES TO
DEVELOP SHOWERS ACROSS SOUTHEAST IDAHO THROUGH THE REST OF THE
MORNING. SURFACE TEMPS CURRENTLY FAVORING RAIN OVER SNOW FOR PIH
AND IDA WITH SNOW LEVELS ABOUT 700 TO 1000 FT ABOVE THE GROUND.
UPPER SLOPES OF THE SOUTHEAST HIGHLANDS CAN EXPECT 2 TO 4 INCHES
OF SNOW TODAY AND TONIGHT. WEATHER SHOULD BECOME MORE SETTLED
BRIEFLY TONIGHT AS A TRANSIENT RIDGE PASSES...BUT THE UPPER LOW
WILL BEGIN MOVING INLAND TUESDAY MORNING AND A SURFACE LOW
DEVELOPING OVER NORTHEAST NEVADA TUESDAY AFTERNOON. AS THE SURFACE
LOW INTENSIFIES OVER THE SALT LAKE TUESDAY NIGHT...EXPECT TO SEE
INCREASING PRECIP ALONG OUR SOUTHERN BORDER WITH SNOW LEVELS
DROPPING TO THE SURFACE. SNOWFALL AMOUNTS FOR TUESDAY NIGHT
THROUGH WEDNESDAY WILL BE ABOUT 4 TO 6 INCHES IN THE SOUTH CENTRAL
HIGHLANDS ABOVE 6500 FT AND LESSER AMOUNTS BELOW. THE UPPER LOW
WILL CONTINUE EASTWARD THROUGH WEDNESDAY AND LEAVE THE AREA ON
THURSDAY. UPSLOPE COMPONENT OF WINDS AT 700MB WILL FAVOR CONTINUED
POPS INTO THURSDAY MORNING OVER THE SOUTHEASTERN HIGHLANDS.
HINSBERGER
.LONG TERM...THURSDAY THROUGH NEXT MONDAY. THE GFS AND ECMWF AGREE
ON DRAGGING A SHALLOW LOW SE THROUGH THE REGION THURSDAY/FRIDAY
RESULTING IN AFTERNOON CONVECTION EACH DAY FAVORING THE NE
HIGHLANDS. A QUICK BREAK FOLLOWS FRIDAY NIGHT AHEAD OF THE NEXT
INCOMING PAC STORM SYSTEM SATURDAY AFTERNOON. THE STORM PASSES
QUICKLY EAST SUNDAY WITH GRADUALLY DRIER CONDITIONS DEVELOPING OVER
THE REGION UNDER A BROAD UPPER RIDGE MONDAY. SEASONABLE TEMPERATURES
ARE EXPECTED THROUGHOUT THE FORECAST PERIOD. HUSTON
&&
.AVIATION...A DEEP LOW PRESSURE SYSTEM WAS NOTED OFF THE
WASHINGTON/OREGON COAST EARLY THIS MORNING WHILE A BROAD AREA OF VFR
CIGS WERE OVERSPREADING SE IDAHO. THE MODELS SHOW THE MOISTURE
DEEPENING OVER THE AREA THROUGH THE MORNING (LOW VFR TO MVFR CIGS)
WITH INCREASING INSTABILITY AND THE POTENTIAL FOR SCT UPPER JET
INDUCED THUNDERSTORMS THIS AFTERNOON. LITTLE AGREEMENT AMONG THE
MODELS AT THIS TIME ON THE FAVORED PLACEMENT OF CONVECTION SO WE
WILL BE JUDICIOUS WITH THE MENTION IN THE TAFS. THE CONVECTION ENDS
BY EARLY EVENING AS DRIER CONDITIONS SPREAD INTO THE AREA AND THE
LOW DROPS FURTHER SOUTH INTO THE NRN CALIFORNIA COASTAL WATERS.
BREEZY SOUTHWEST WINDS ARE EXPECTED THROUGHOUT THE SNAKE RIVER PLAIN
TODAY. HUSTON
&&
.PIH WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1006 PM CDT TUE APR 7 2015
.UPDATE...900 PM CDT
WE HAVE MADE SOME CHANGES TO CUT BACK ON POPS A BIT OVER THE AREA
TONIGHT. CONVECTIVE TRENDS THIS EVENING ASSOCIATED WITH THE UPPER
LEVEL DISTURBANCE SHIFTING EASTWARD OVER NORTHEASTERN IOWA HAS
LARGELY SUGGESTED THAT MOST OF THE ACTIVITY WILL REMAIN RIGHT
ALONG OR JUST NORTH OF THE ILLINOIS BOARDER IN SOUTHERN WISCONSIN.
AS SUCH...I HAVE CUT POPS DOWN...ESPECIALLY SOUTH OF I88.
THE 00 UTC SOUNDING OUT OF KILX INDICATES SOME STEEP MID-LEVEL LAPSE
RATES...BUT REMAINS CAPPED TO ELEVATED CONVECTION. THEREFORE...IN
THE SHORT TERM PERIOD...THROUGH AT LEAST 06 UTC...IT APPEARS
UNLIKELY THAT ANY ACTIVITY WILL DEVELOP SOUTH OF THE CURRENT
ACTIVITY. HOWEVER...SOME HIRES GUIDANCE SUGGESTS THAT SOME WIDELY
SCATTERED STORMS COULD DEVELOP ACROSS MY SOUTHERN CWA VERY LATE
TONIGHT IN CLOSER PROXIMATE TO THE SURFACE FRONTAL ZONE...IN
ASSOCIATION WITH SOME BETTER MOISTURE TRANSPORT ALONG THE LOW LEVEL
JET. CONFIDENCE IS NOT THE GREATEST THAT THIS WILL MATERIALIZE
HOWEVER...BUT IF ANY STORMS WERE TO DEVELOP...THE STEEP LAPSE RATES
COULD SUPPORT A SMALL HAIL THREAT. IT APPEARS THE BEST CHANCES FOR
THIS WILL BE AFTER 09 UTC THROUGH EARLY THURSDAY MORNING.
IT ALSO APPEARS THE MAIN THREAT FOR DENSE FOG MAY REMAIN IN CLOSER
PROXIMATE TO THE SURFACE FRONTAL ZONE TO OUR SOUTH...WHERE DEW
POINTS ARE INTO THE 50S. THEREFORE...WHILE THERE WILL LIKELY
CONTINUE TO BE FOG WITH 1 TO 3 SM VISIBILITIES OVER THE AREA...IT
APPEARS LESS LIKELY FOR DENSE FOG DEVELOPMENT OVERNIGHT OVER
FAR NORTHERN ILLINOIS.
KJB
&&
.SHORT TERM...
327 PM CDT
THROUGH WEDNESDAY NIGHT...
STRONG QUASI-STATIONARY FRONT IS DRAPED ACROSS CENTRAL ILLINOIS WITH
WARM AND HUMID AIR RESIDING SOUTH OF THIS BOUNDARY WITH 60 DEGREE
DEWPOINTS BUTTING UP AGAINST OUR SOUTHERN MOST CWA BORDER. TO THE
NORTH OF THE BOUNDARY YOU JUMP BACK A SEASON WITH BRISK NORTHEAST
WINDS AND CLOUDINESS HOLDING TEMPS IN THE 40S...EXCEPT NEAR THE LAKE
WHERE TEMPS ARE STILL IN THE UPPER 30S WITH SOME MARINE FOG. WEBCAMS
CONTINUE TO SUGGEST DENSEST FOG IS RIGHT AT THE SHORE...THOUGH STILL
EXPECT THAT THIS FOG COULD BEGIN TO OOZE INLAND WITH TIME TONIGHT
AND POSSIBLY INTO WEDNESDAY AS WELL. FRONTAL BOUNDARY WILL LIKELY
WAVER AROUND A BIT THROUGH WEDNESDAY NIGHT...POTENTIALLY CREEPING
NORTH INTO OUR SOUTHERN CWA AT TIMES WHICH WILL UNDOUBTEDLY CAUSE
HAVOC IN MAINTAINING HOURLY TEMPERATURE GRIDS AND PLACES A HIGHER
DEGREE THAN NORMAL OF UNCERTAINTY IN HIGH AND LOW TEMP FORECAST THE
NEXT 36 HOURS.
WATER VAPOR IMAGERY SHOWS A WELL DEFINED SHORTWAVE MOVING EASTWARD
INTO THE WESTERN CORNBELT THIS AFTERNOON WITH WAA IN ADVANCE OF THIS
FEATURE RESULTING IN AN INCREASE IN COVERAGE OF SHOWERS AND
THUNDERSTORMS ACROSS IOWA THIS AFTERNOON. GIVEN THE FARTHER
SOUTHWARD PLACEMENT OF THE FRONTAL BOUNDARY AND INSTABILITY AXIS I
SUSPECT THAT THIS ACTIVITY WILL HAVE A TENDENCY TO PROPAGATE/DEVELOP
SOUTHWARD WITH AN INCREASE IN COVERAGE AND INTENSITY THIS EVENING
WITH THE NOCTURNAL STRENGTHENING OF THE LOW LEVEL JET. PWATS OF
AROUND 200 PERCENT OF NORMAL SUGGEST THAT ANY THUNDERSTORMS THAT DO
DEVELOP COULD BE VERY EFFICIENT RAIN PRODUCERS. EXTRAPOLATION HAS
THAT SHORTWAVE MOVING EAST OF OUR AREA BY 06Z SUGGESTING MOST
ORGANIZED PRECIP SHOULD SHIFT EAST WITH IT THOUGH CONTINUED WAA
OVER TOP SHALLOW COLD AIR MASS DOES RAISE AT LEAST THE POTENTIAL OF
CONTINUED CONVECTIVE DEVELOPMENT INTO THE OVERNIGHT HOURS.
CANNOT RULE OUT SOME LINGERING MORE SHOWERS...MAINLY EASTERN
CWA...BUT OVERALL WEDNESDAY LOOKS TO BE DRY OTHER THAN SOME POSSIBLE
DRIZZLE WITH THE THICKER FOG NEAR THE LAKE. NEXT SHORTWAVE AND
ASSOCIATED RAMPING OF LOW LEVEL JET/WAA LOOKS TO BE WEDNESDAY NIGHT
WHEN ONCE AGAIN LOCALLY HEAVY RAINFALL WILL BE A DISTINCT
POSSIBILITY. ANTECEDENT CONDITIONS ARE GENERALLY PRETTY DRY...SO
OTHER THAN URBAN AREAS OR REMOTE THREAT OF EXTREME RAINFALL TOTALS
THINK THE FLASH FLOOD CONCERNS LOOK NOT TOO IMPRESSIVE AT THIS
TIME.
IZZI
&&
.LONG TERM...
327 PM CDT
THURSDAY NIGHT THROUGH TUESDAY...
PRIMARY TROUGH IS STILL PROGGED TO MOVE QUICKLY EASTWARD AND INTO
THE MIDWEST BY THURSDAY AFTERNOON. GUIDANCE VARIES SOME WITH RESPECT
TO TIMING/INTENSITY OF THIS SYSTEM WITH 12Z ECMWF ON THE
FASTER/WEAKER END OF THE GUIDANCE SPECTRUM AND THE NAM/GEM ON THE
SLOWER DEEPER END OF THE SPECTRUM. OFTEN TIMES THE SLOWER GUIDANCE
ENDS UP VERIFYING BETTER WITH THESE STRONGER SYSTEMS...SO TRENDED
THE GRIDS TOWARD THE NAM/GEM SOLUTION. THE GFS SUPPORTS THE IDEA OF
STRONGER SYSTEM BUT SUSPECT IT IS A BIT TOO FAST.
SYNOPTICALLY SPEAKING THE LARGE SCALE PATTERN AND EVOLUTION OF THIS
CYCLONE CONTINUE TO RAISE RED FLAGS FOR THE POTENTIAL OF A
SIGNIFICANT SEVERE WEATHER EPISODE IN THE REGION THURSDAY AFTERNOON
AND EVENING. THE KINEMATIC FIELDS ARE EXTREMELY IMPRESSIVE WITH 90-
100KT UPPER LEVEL JET NOSING INTO THE REGION IN THE AFTERNOON WITH
40KT+ LOW LEVEL JET RESULTING IN VERY FAVORABLE DEEP LAYER SHEAR
PROFILE FOR SEVERE WEATHER. THE MAGNITUDE OF LOW LEVEL SHEAR WHICH
WILL PLAY A ROLE IN THE MAGNITUDE OF A TORNADO THREAT VARIES
DEPENDING ON THE MODEL. THE DEEPER SOLUTIONS HAVE A MORE BACKED
SURFACE FLOW AND LARGER LOW LEVEL HODOGRAPHS AND WOULD BE MUCH MORE
WORRISOME REGARDING TORNADO THREAT.
THE LATEST MODEL RUNS THIS MORNING ALSO SUGGEST AN UNUSUALLY
IMPRESSIVE PLUME OF STEEP MID LEVEL LAPSE RATES FOR SO FAR EASTWARD
BECOME JUXTAPOSED OVER TOP A WARM AND HUMID AIR MASS WITH SURFACE
DEWPOINTS LIKELY IN THE 60S WITHIN THE WARM SECTOR. GIVEN THE
PROGGED INTENSITY OF THE SYSTEM SUSPECT THAT EVEN MORNING CONVECTION
WILL NOT BE ENOUGH TO PREVENT THE WARM FRONT FROM BLASTING NORTH AND
PLACING ENTIRE CWA IN THE HUMID/UNSTABLE WARM SECTOR BY AFTERNOON.
OBVIOUSLY THERE ARE A TON OF MESOSCALE DETAILS THAT CANNOT BE
RESOLVED AT THIS DISTANCE...INCLUDING STORM MODE AND COVERAGE. THERE
IS A LOT THAT CAN CHANGE BETWEEN NOW AND THURSDAY SO A SIGNIFICANT
SEVERE WEATHER EVENT IS FAR FROM A SURE THING...BUT GIVEN THE TRENDS
IN MODEL GUIDANCE AND SYNOPTIC PATTERN THERE IS DEFINITELY REASON
FOR CONCERN ABOUT THE SEVERE WEATHER AND TORNADO POTENTIAL THURSDAY
AFTERNOON AND EVENING.
COOLER/DRIER PACIFIC AIR WILL FILTER INTO THE REGION FRIDAY ON BRISK
WESTERLY WINDS...FOLLOWED BY A MODERATING TREND HEADING INTO THE
WEEKEND IN ADVANCE OF THE NEXT SYSTEM WHICH LOOKS TO ARRIVE LATE
SUNDAY OR MONDAY WITH OUR NEXT SHOT OF SHOWERS AND THUNDERSTORMS.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* CONTINUED IFR CIGS POSSIBLY SOME LIFR CIGS.
* VSBYS MAINLY IFR.
* CHC OF FOR RAIN/THUNDER OVERNIGHT AND ENDING PRIOR TO DAYBREAK
WED.
* NORTHEAST WINDS PERSIST...OCCASIONAL GUSTS TO 20KT.
* IFR CONDS CONTINUE WED.
BEACHLER
//DISCUSSION...UPDATED 00Z...
VERY MOIST AIRMASS CONTINUES TO FEED ACROSS NORTHERN IL/NORTHWEST
IN AIRFIELDS THIS EVENING AND LIKELY WILL PERSIST THROUGH WED.
CURRENT REGIONAL RADAR IMAGERY INDICATES ONE AREA OF SHOWERS AND
THUNDERSTORMS ACROSS NORTHEAST IOWA AND SOUTHWEST WISC...AND WAS
SLIDING EAST. THIS FIRST PRECIP SLUG WILL LIKELY CLIP RFD/ORD/DPA
TAF SITES BETWEEN 2-4Z...THEN GUIDANCE CONTINUES TO SUGGEST
ANOTHER WAVE OF SHOWERS AND LIKELY CONVECTION WILL ARRIVE
OVERNIGHT OR CLOSER TO 8Z.
THE UNFORTUNATE POSITION IS THAT IFR CIGS/VSBYS LOOK TO PREVAIL
THROUGH THE NEXT 24 HOURS...WITH JUST A FEW BRIEF POCKETS OF
IMPROVEMENT IN AND AROUND THE RAIN/THUNDER THAT MAY OCCUR TONIGHT.
NORTHEAST/EAST WINDS WILL ALSO PERSIST...WITH OCCASIONAL GUSTS TO
20KT TONIGHT. THERE MAY BE A BRIEF PERIOD OF CIGS DIPPING TO LIFR
CONDS TONIGHT...BUT CONFIDENCE IS LOW ON THE DURATION.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED...MEDIUM CONFIDENCE IN GUSTS
SPEED AND DURATION OF GUSTS.
* MEDIUM/HIGH CONFIDENCE CIGS REMAIN IFR...MEDIUM CONFIDENCE IN
BRIEF LIFR CIGS LATER THIS EVENING.
* MEDIUM/HIGH CONFIDENCE IN PRECIP TIMING AND COVERAGE. MEDIUM
CONFIDENCE IN THUNDER TIMING/DURATION.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY...STRONG TSRA. MVFR. STRONG/GUSTY SOUTH/SOUTHWEST
WINDS.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...DRY/VFR. SOUTHEAST WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. MVFR POSSIBLE. SOUTH WINDS.
BEACHLER
&&
.MARINE...
340 PM CDT
A PERIOD OF ACTIVE WEATHER IS UNDERWAY FOR LAKE MICHIGAN. AS OF
TUESDAY AFTERNOON...A STATIONARY FRONTAL BOUNDARY LIES SOUTH OF THE
LAKE WHILE STRONG HIGH PRESSURE TRACKS ACROSS EASTERN ONTARIO INTO
QUEBEC. BETWEEN THE FRONTAL TROUGH TO THE SOUTH LAKE AND THE HIGH
TO THE NORTH...PERSISTENT NORTHEAST TO EAST WINDS OF 25 TO 30 KT
WILL COVER THE LAKE...WITH THE STRONGEST WINDS OVER THE NORTHERN
PORTIONS OF THE LAKE. DEWPOINTS HAVE BEEN INCREASING OVER THE
SOUTHERN PORTIONS OF THE LAKE...LEADING TO THE FORMATION OF DENSE
FOG...ESPECIALLY FOR THE SOUTHERN PORTIONS OF THE LAKE. LOW PRESSURE
DEVELOPING OVER THE WESTERN PLAINS WILL QUICKLY DEEPEN AND TRACK TO
NORTHERN WISCONSIN...FORCING THE STATIONARY FRONT NORTH AS A WARM
FRONT. WINDS WILL SHIFT FROM ELY-SELY TO SWLY FOLLOWING THE PASSAGE
OF THE WARM FRONT AND TEMPORARILY SUBSIDE...BUT A STRENGTHENING
GRADIENT AHEAD OF AN APPROACHING COLD FRONT WILL HELP STRENGTHEN
WINDS BACK TO 25 TO 30 KT. THE COLD FRONT TRAILING SOUTHWEST FROM
THE FAST-MOVING LOW WILL SWEEP ACROSS THE LAKE ON SATURDAY. HIGH
PRESSURE IS EXPECTED TO SPREAD ACROSS THE LAKE ON
SATURDAY...USHERING IN A PERIOD OF QUIETER WEATHER THAT SHOULD
PERSIST INTO EARLY NEXT WEEK.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 5 AM
THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
912 PM CDT Tue Apr 7 2015
.UPDATE...
ISSUED AT 902 PM CDT TUE APR 7 2015
The stationary front is not making much progress northward yet
this evening. The latest sfc analysis shows the front still
lingering between I-72 and I-70 at 02z/9pm. Minor clearing has
developed toward SPI and Jacksonville, but the last hour clouds
have begun to re-develop in response to an inversion and trapped
low level moisture. Have continued with including fog along and
north of I-74 the rest of the night, with some dense fog ongoing
around BMI.
Low pressure is expected to advance along the front tonight,
helping to give it a northward push. Showers and storms should
accompany the arrival of the low, with the help of a 500mb
shortwave and increasing instability. Storms will increase in
coverage from west to east after 06z/1am. The storms will be
elevated, so hail will be more of a concern than very strong wind
gusts. No severe storms are anticipated with the wave of storms
later tonight, as the overall system dynamics will be weakening
with time as it moves across Illinois.
Forecast updates included: delaying the onset of precip for a few
more hours, diminished PoPs NW of the IL river late tonight,
adjusted hourly temps to try to match expected frontal boundary
movement northward. Updated forecast info is already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 301 PM CDT TUE APR 7 2015
A quasi stationary front remains over central IL between I-70 and
I-72. The frontal boundary should start to slowly push back
northward across central IL later this evening and overnight as 1007
mb low pressure over northeast KS tracks into central IL by Wed
morning. An MCS was bringing showers and a few thunderstorms to
southeast IL at mid afternoon while the strong to severe storms with
heavy rains were south of highway 50 and approaching the Ohio river
as they tracked eastward. pushes southward, wavering over central
Illinois, southerly flow will continue to bring in more boundary
layer moisture. Scattered showers and thunderstorms will develop
during tonight along this boundary over central IL as low pressure
approaches and frontal boundary starts to lift back north with ample
moisture. Some fog still lingering north of I-72 and added some fog
to areas north of this boundary tonight especially from I-74
northward. Lows tonight mostly in the upper 50s and lower 60s,
except cooler low to mid 50s from Galesburg to Peoria and
Bloomington northward which stays north of the boundary much of the
night.
&&
.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 301 PM CDT TUE APR 7 2015
Not too much has changed in the large scale pattern/expected weather
over the next few days. However, things will continue to be tricky
with respect to the convective details and temperatures due to the
wobbling surface boundary and model disagreement in the ultimate
strength of the main low/frontal passage for Thursday.
The frontal boundary that currently lies west-east across the
Midwest will not move appreciably through Wednesday. Nearly
continuous WAA/isentropic ascent is progged through a deep layer
across the area until the main system arrives heading into Wednesday
night. Until the system approaches, forecast soundings (and 12Z KILX
sounding for that matter) suggest a persistent elevated mixed layer,
but also a fairly stout low level capping inversion. Moisture
continues to be lacking within the EML, so PoPs will stay on the
lower side for most of Wednesday.
The remnants of the Pacific Coast will help force the frontal
boundary back northward Wednesday night as it pushes across the
Plains. This will spread more widespread showers/storms across the
area as early as late Wednesday afternoon into Wednesday night.
There will be ample shear for some of the storms to be on the
stronger side, but they should be elevated in nature for the most
part and most apt to be hail producers.
The main low/cold front are still on tap to cross the region
Thursday into Thursday evening, although there are still
considerable timing/strength differences. The ECMWF continues to be
much weaker and (not surprisingly) several hours slower than the
building model consensus. Do not have a compelling reason to
disregard the ECMWF, but have leaned more toward the larger model
consensus. This scenario supports strong/severe storms across the
forecast area along/ahead of the front on Thursday, mainly during
the afternoon. Instability and shear profiles are both expected to
be more than respectable, with CAPE values averaging 1500-2500 j/kg,
and bulk shear values from 35-45 kts.
The cold front is expected to clear most of the area by late
Thursday evening, ushering in quieter weather until Sunday. Then,
another storm system will bring renewed shower/storm chances to
start out next week. However, model spread and run-to-run
consistency in the details continues to be poor at best. This is
resulting in an extended period of PoPs from what should only be one
system passage. Hopefully a better agreed upon solution develops
soon.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 700 PM CDT TUE APR 7 2015
A stationary front extending across central IL, just south of
I-72, is forecast to drift slowly northward this evening. Clearing
has developed under the front for SPI, with DEC and CMI expected
to see clearing from MVFR clouds to VFR in the next hour or so.
BMI has remained LIFR due to 200ft cigs, with vis now at 3/4sm BR.
Farther north of the front, IFR clouds appear poised to continue
across PIA for the bulk of the night. IFR/MVFR clouds are forecast to
re-develop at all terminal sites overnight as a subsidence
inversion traps moisture in the low levels and the boundary layer
airmass cools.
The HRRR model output is pointing toward a complex of showers and
thunderstorms developing later this evening in far western IL and
advancing across our terminal sites after 06z. Weakening low
pressure is progged to advance into central IL around 12z, then
dissipate before it reaches Indiana. That will keep storm chances
going through around mid-morning.
Can`t rule out periodic improvements in ceiling and vis later tonight
as storms pass through and increase low level mixing. Will prevail
the lower conditions for now.
ESE winds of 10-15kt will diminish to 7-10kt overnight, with wind
directions highly dependent on how far north the stationary front
drifts by morning. Winds tomorrow morning could become variable
under the front, and eventually prevail from the NE for PIA/BMI
and southwest for SPI/DEC/CMI. The GFS and NAM have differing wind
solutions, but went closer to the NAM with this set of TAFs.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Shimon
SHORT TERM...07
LONG TERM...Bak
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
705 PM CDT TUE APR 7 2015
.SHORT TERM...
327 PM CDT
THROUGH WEDNESDAY NIGHT...
STRONG QUASI-STATIONARY FRONT IS DRAPED ACROSS CENTRAL ILLINOIS WITH
WARM AND HUMID AIR RESIDING SOUTH OF THIS BOUNDARY WITH 60 DEGREE
DEWPOINTS BUTTING UP AGAINST OUR SOUTHERN MOST CWA BORDER. TO THE
NORTH OF THE BOUNDARY YOU JUMP BACK A SEASON WITH BRISK NORTHEAST
WINDS AND CLOUDINESS HOLDING TEMPS IN THE 40S...EXCEPT NEAR THE LAKE
WHERE TEMPS ARE STILL IN THE UPPER 30S WITH SOME MARINE FOG. WEBCAMS
CONTINUE TO SUGGEST DENSEST FOG IS RIGHT AT THE SHORE...THOUGH STILL
EXPECT THAT THIS FOG COULD BEGIN TO OOZE INLAND WITH TIME TONIGHT
AND POSSIBLY INTO WEDNESDAY AS WELL. FRONTAL BOUNDARY WILL LIKELY
WAVER AROUND A BIT THROUGH WEDNESDAY NIGHT...POTENTIALLY CREEPING
NORTH INTO OUR SOUTHERN CWA AT TIMES WHICH WILL UNDOUBTEDLY CAUSE
HAVOC IN MAINTAINING HOURLY TEMPERATURE GRIDS AND PLACES A HIGHER
DEGREE THAN NORMAL OF UNCERTAINTY IN HIGH AND LOW TEMP FORECAST THE
NEXT 36 HOURS.
WATER VAPOR IMAGERY SHOWS A WELL DEFINED SHORTWAVE MOVING EASTWARD
INTO THE WESTERN CORNBELT THIS AFTERNOON WITH WAA IN ADVANCE OF THIS
FEATURE RESULTING IN AN INCREASE IN COVERAGE OF SHOWERS AND
THUNDERSTORMS ACROSS IOWA THIS AFTERNOON. GIVEN THE FARTHER
SOUTHWARD PLACEMENT OF THE FRONTAL BOUNDARY AND INSTABILITY AXIS I
SUSPECT THAT THIS ACTIVITY WILL HAVE A TENDENCY TO PROPAGATE/DEVELOP
SOUTHWARD WITH AN INCREASE IN COVERAGE AND INTENSITY THIS EVENING
WITH THE NOCTURNAL STRENGTHENING OF THE LOW LEVEL JET. PWATS OF
AROUND 200 PERCENT OF NORMAL SUGGEST THAT ANY THUNDERSTORMS THAT DO
DEVELOP COULD BE VERY EFFICIENT RAIN PRODUCERS. EXTRAPOLATION HAS
THAT SHORTWAVE MOVING EAST OF OUR AREA BY 06Z SUGGESTING MOST
ORGANIZED PRECIP SHOULD SHIFT EAST WITH IT THOUGH CONTINUED WAA
OVER TOP SHALLOW COLD AIR MASS DOES RAISE AT LEAST THE POTENTIAL OF
CONTINUED CONVECTIVE DEVELOPMENT INTO THE OVERNIGHT HOURS.
CANNOT RULE OUT SOME LINGERING MORE SHOWERS...MAINLY EASTERN
CWA...BUT OVERALL WEDNESDAY LOOKS TO BE DRY OTHER THAN SOME POSSIBLE
DRIZZLE WITH THE THICKER FOG NEAR THE LAKE. NEXT SHORTWAVE AND
ASSOCIATED RAMPING OF LOW LEVEL JET/WAA LOOKS TO BE WEDNESDAY NIGHT
WHEN ONCE AGAIN LOCALLY HEAVY RAINFALL WILL BE A DISTINCT
POSSIBILITY. ANTECEDENT CONDITIONS ARE GENERALLY PRETTY DRY...SO
OTHER THAN URBAN AREAS OR REMOTE THREAT OF EXTREME RAINFALL TOTALS
THINK THE FLASH FLOOD CONCERNS LOOK NOT TOO IMPRESSIVE AT THIS
TIME.
IZZI
&&
.LONG TERM...
327 PM CDT
THURSDAY NIGHT THROUGH TUESDAY...
PRIMARY TROUGH IS STILL PROGGED TO MOVE QUICKLY EASTWARD AND INTO
THE MIDWEST BY THURSDAY AFTERNOON. GUIDANCE VARIES SOME WITH RESPECT
TO TIMING/INTENSITY OF THIS SYSTEM WITH 12Z ECMWF ON THE
FASTER/WEAKER END OF THE GUIDANCE SPECTRUM AND THE NAM/GEM ON THE
SLOWER DEEPER END OF THE SPECTRUM. OFTEN TIMES THE SLOWER GUIDANCE
ENDS UP VERIFYING BETTER WITH THESE STRONGER SYSTEMS...SO TRENDED
THE GRIDS TOWARD THE NAM/GEM SOLUTION. THE GFS SUPPORTS THE IDEA OF
STRONGER SYSTEM BUT SUSPECT IT IS A BIT TOO FAST.
SYNOPTICALLY SPEAKING THE LARGE SCALE PATTERN AND EVOLUTION OF THIS
CYCLONE CONTINUE TO RAISE RED FLAGS FOR THE POTENTIAL OF A
SIGNIFICANT SEVERE WEATHER EPISODE IN THE REGION THURSDAY AFTERNOON
AND EVENING. THE KINEMATIC FIELDS ARE EXTREMELY IMPRESSIVE WITH 90-
100KT UPPER LEVEL JET NOSING INTO THE REGION IN THE AFTERNOON WITH
40KT+ LOW LEVEL JET RESULTING IN VERY FAVORABLE DEEP LAYER SHEAR
PROFILE FOR SEVERE WEATHER. THE MAGNITUDE OF LOW LEVEL SHEAR WHICH
WILL PLAY A ROLE IN THE MAGNITUDE OF A TORNADO THREAT VARIES
DEPENDING ON THE MODEL. THE DEEPER SOLUTIONS HAVE A MORE BACKED
SURFACE FLOW AND LARGER LOW LEVEL HODOGRAPHS AND WOULD BE MUCH MORE
WORRISOME REGARDING TORNADO THREAT.
THE LATEST MODEL RUNS THIS MORNING ALSO SUGGEST AN UNUSUALLY
IMPRESSIVE PLUME OF STEEP MID LEVEL LAPSE RATES FOR SO FAR EASTWARD
BECOME JUXTAPOSED OVER TOP A WARM AND HUMID AIR MASS WITH SURFACE
DEWPOINTS LIKELY IN THE 60S WITHIN THE WARM SECTOR. GIVEN THE
PROGGED INTENSITY OF THE SYSTEM SUSPECT THAT EVEN MORNING CONVECTION
WILL NOT BE ENOUGH TO PREVENT THE WARM FRONT FROM BLASTING NORTH AND
PLACING ENTIRE CWA IN THE HUMID/UNSTABLE WARM SECTOR BY AFTERNOON.
OBVIOUSLY THERE ARE A TON OF MESOSCALE DETAILS THAT CANNOT BE
RESOLVED AT THIS DISTANCE...INCLUDING STORM MODE AND COVERAGE. THERE
IS A LOT THAT CAN CHANGE BETWEEN NOW AND THURSDAY SO A SIGNIFICANT
SEVERE WEATHER EVENT IS FAR FROM A SURE THING...BUT GIVEN THE TRENDS
IN MODEL GUIDANCE AND SYNOPTIC PATTERN THERE IS DEFINITELY REASON
FOR CONCERN ABOUT THE SEVERE WEATHER AND TORNADO POTENTIAL THURSDAY
AFTERNOON AND EVENING.
COOLER/DRIER PACIFIC AIR WILL FILTER INTO THE REGION FRIDAY ON BRISK
WESTERLY WINDS...FOLLOWED BY A MODERATING TREND HEADING INTO THE
WEEKEND IN ADVANCE OF THE NEXT SYSTEM WHICH LOOKS TO ARRIVE LATE
SUNDAY OR MONDAY WITH OUR NEXT SHOT OF SHOWERS AND THUNDERSTORMS.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* CONTINUED IFR CIGS POSSIBLY SOME LIFR CIGS.
* VSBYS MAINLY IFR.
* CHC OF SHOWERS THIS EVENING...THEN ANOTHER CHANCE FOR
RAIN/THUNDER OVERNIGHT AND ENDING PRIOR TO DAYBREAK WED.
* NORTHEAST WINDS PERSIST...OCCASIONAL GUSTS TO 20KT.
* IFR CONDS CONTINUE WED.
BEACHLER
//DISCUSSION...UPDATED 00Z...
VERY MOIST AIRMASS CONTINUES TO FEED ACROSS NORTHERN IL/NORTHWEST
IN AIRFIELDS THIS EVENING AND LIKELY WILL PERSIST THROUGH WED.
CURRENT REGIONAL RADAR IMAGERY INDICATES ONE AREA OF SHOWERS AND
THUNDERSTORMS ACROSS NORTHEAST IOWA AND SOUTHWEST WISC...AND WAS
SLIDING EAST. THIS FIRST PRECIP SLUG WILL LIKELY CLIP RFD/ORD/DPA
TAF SITES BETWEEN 2-4Z...THEN GUIDANCE CONTINUES TO SUGGEST
ANOTHER WAVE OF SHOWERS AND LIKELY CONVECTION WILL ARRIVE
OVERNIGHT OR CLOSER TO 8Z.
THE UNFORTUNATE POSITION IS THAT IFR CIGS/VSBYS LOOK TO PREVAIL
THROUGH THE NEXT 24 HOURS...WITH JUST A FEW BRIEF POCKETS OF
IMPROVEMENT IN AND AROUND THE RAIN/THUNDER THAT MAY OCCUR TONIGHT.
NORTHEAST/EAST WINDS WILL ALSO PERSIST...WITH OCCASIONAL GUSTS TO
20KT TONIGHT. THERE MAY BE A BRIEF PERIOD OF CIGS DIPPING TO LIFR
CONDS TONIGHT...BUT CONFIDENCE IS LOW ON THE DURATION.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE IN WIND DIR/SPEED...MEDIUM CONFIDENCE IN GUSTS
SPEED AND DURATION OF GUSTS.
* MEDIUM/HIGH CONFIDENCE CIGS REMAIN IFR...MEDIUM CONFIDENCE IN
BRIEF LIFR CIGS LATER THIS EVENING.
* MEDIUM/HIGH CONFIDENCE IN PRECIP TIMING AND COVERAGE. MEDIUM
CONFIDENCE IN THUNDER TIMING/DURATION.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY...STRONG TSRA. MVFR. STRONG/GUSTY SOUTH/SOUTHWEST
WINDS.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...DRY/VFR. SOUTHEAST WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. MVFR POSSIBLE. SOUTH WINDS.
BEACHLER
&&
.MARINE...
340 PM CDT
A PERIOD OF ACTIVE WEATHER IS UNDERWAY FOR LAKE MICHIGAN. AS OF
TUESDAY AFTERNOON...A STATIONARY FRONTAL BOUNDARY LIES SOUTH OF THE
LAKE WHILE STRONG HIGH PRESSURE TRACKS ACROSS EASTERN ONTARIO INTO
QUEBEC. BETWEEN THE FRONTAL TROUGH TO THE SOUTH LAKE AND THE HIGH
TO THE NORTH...PERSISTENT NORTHEAST TO EAST WINDS OF 25 TO 30 KT
WILL COVER THE LAKE...WITH THE STRONGEST WINDS OVER THE NORTHERN
PORTIONS OF THE LAKE. DEWPOINTS HAVE BEEN INCREASING OVER THE
SOUTHERN PORTIONS OF THE LAKE...LEADING TO THE FORMATION OF DENSE
FOG...ESPECIALLY FOR THE SOUTHERN PORTIONS OF THE LAKE. LOW PRESSURE
DEVELOPING OVER THE WESTERN PLAINS WILL QUICKLY DEEPEN AND TRACK TO
NORTHERN WISCONSIN...FORCING THE STATIONARY FRONT NORTH AS A WARM
FRONT. WINDS WILL SHIFT FROM ELY-SELY TO SWLY FOLLOWING THE PASSAGE
OF THE WARM FRONT AND TEMPORARILY SUBSIDE...BUT A STRENGTHENING
GRADIENT AHEAD OF AN APPROACHING COLD FRONT WILL HELP STRENGTHEN
WINDS BACK TO 25 TO 30 KT. THE COLD FRONT TRAILING SOUTHWEST FROM
THE FAST-MOVING LOW WILL SWEEP ACROSS THE LAKE ON SATURDAY. HIGH
PRESSURE IS EXPECTED TO SPREAD ACROSS THE LAKE ON
SATURDAY...USHERING IN A PERIOD OF QUIETER WEATHER THAT SHOULD
PERSIST INTO EARLY NEXT WEEK.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 5 AM
THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
703 PM CDT Tue Apr 7 2015
.SHORT TERM...(Tonight)
ISSUED AT 301 PM CDT TUE APR 7 2015
A quasi stationary front remains over central IL between I-70 and
I-72. The frontal boundary should start to slowly push back
northward across central IL later this evening and overnight as 1007
mb low pressure over northeast KS tracks into central IL by Wed
morning. An MCS was bringing showers and a few thunderstorms to
southeast IL at mid afternoon while the strong to severe storms with
heavy rains were south of highway 50 and approaching the Ohio river
as they tracked eastward. pushes southward, wavering over central
Illinois, southerly flow will continue to bring in more boundary
layer moisture. Scattered showers and thunderstorms will develop
during tonight along this boundary over central IL as low pressure
approaches and frontal boundary starts to lift back north with ample
moisture. Some fog still lingering north of I-72 and added some fog
to areas north of this boundary tonight especially from I-74
northward. Lows tonight mostly in the upper 50s and lower 60s,
except cooler low to mid 50s from Galesburg to Peoria and
Bloomington northward which stays north of the boundary much of the
night.
&&
.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 301 PM CDT TUE APR 7 2015
Not too much has changed in the large scale pattern/expected weather
over the next few days. However, things will continue to be tricky
with respect to the convective details and temperatures due to the
wobbling surface boundary and model disagreement in the ultimate
strength of the main low/frontal passage for Thursday.
The frontal boundary that currently lies west-east across the
Midwest will not move appreciably through Wednesday. Nearly
continuous WAA/isentropic ascent is progged through a deep layer
across the area until the main system arrives heading into Wednesday
night. Until the system approaches, forecast soundings (and 12Z KILX
sounding for that matter) suggest a persistent elevated mixed layer,
but also a fairly stout low level capping inversion. Moisture
continues to be lacking within the EML, so PoPs will stay on the
lower side for most of Wednesday.
The remnants of the Pacific Coast will help force the frontal
boundary back northward Wednesday night as it pushes across the
Plains. This will spread more widespread showers/storms across the
area as early as late Wednesday afternoon into Wednesday night.
There will be ample shear for some of the storms to be on the
stronger side, but they should be elevated in nature for the most
part and most apt to be hail producers.
The main low/cold front are still on tap to cross the region
Thursday into Thursday evening, although there are still
considerable timing/strength differences. The ECMWF continues to be
much weaker and (not surprisingly) several hours slower than the
building model consensus. Do not have a compelling reason to
disregard the ECMWF, but have leaned more toward the larger model
consensus. This scenario supports strong/severe storms across the
forecast area along/ahead of the front on Thursday, mainly during
the afternoon. Instability and shear profiles are both expected to
be more than respectable, with CAPE values averaging 1500-2500 j/kg,
and bulk shear values from 35-45 kts.
The cold front is expected to clear most of the area by late
Thursday evening, ushering in quieter weather until Sunday. Then,
another storm system will bring renewed shower/storm chances to
start out next week. However, model spread and run-to-run
consistency in the details continues to be poor at best. This is
resulting in an extended period of PoPs from what should only be one
system passage. Hopefully a better agreed upon solution develops
soon.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 700 PM CDT TUE APR 7 2015
A stationary front extending across central IL, just south of
I-72, is forecast to drift slowly northward this evening. Clearing
has developed under the front for SPI, with DEC and CMI expected
to see clearing from MVFR clouds to VFR in the next hour or so.
BMI has remained LIFR due to 200ft cigs, with vis now at 3/4sm BR.
Farther north of the front, IFR clouds appear poised to continue
across PIA for the bulk of the night. IFR/MVFR clouds are forecast to
re-develop at all terminal sites overnight as a subsidence
inversion traps moisture in the low levels and the boundary layer
airmass cools.
The HRRR model output is pointing toward a complex of showers and
thunderstorms developing later this evening in far western IL and
advancing across our terminal sites after 06z. Weakening low
pressure is progged to advance into central IL around 12z, then
dissipate before it reaches Indiana. That will keep storm chances
going through around mid-morning.
Can`t rule out periodic improvements in ceiling and vis later tonight
as storms pass through and increase low level mixing. Will prevail
the lower conditions for now.
ESE winds of 10-15kt will diminish to 7-10kt overnight, with wind
directions highly dependent on how far north the stationary front
drifts by morning. Winds tomorrow morning could become variable
under the front, and eventually prevail from the NE for PIA/BMI
and southwest for SPI/DEC/CMI. The GFS and NAM have differing wind
solutions, but went closer to the NAM with this set of TAFs.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...07
LONG TERM...Bak
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
106 PM CDT MON APR 6 2015
.UPDATE...
1112 AM CDT
FORECAST GENERALLY ON TRACK THROUGH THE AFTERNOON. A COLD FRONT IS
STILL MAKING SOUTHWARD PROGRESS...BUT IS STILL NORTH OF THE
WISCONSIN BORDER. EXPECT THE FRONT TO CONTINUE TO SLOWLY MOVE
SOUTH...REACHING THE NORTHERN TIER COUNTIES BY LATE AFTERNOON AND
THEN GOING STATIONARY ACROSS CENTRAL IL/IN OVERNIGHT. THE ONLY
ADJUSTMENT TO THE GOING FORECAST HAS BEEN TO LOWER POPS OVER THE
WRN PORTIONS OF THE CWA...WITH ONLY SLIGHT CHANCE POPS FOR
LOCATIONS WEST OF THE I-39 CORRIDOR BY 23Z SINCE THE AIRMASS IN
PLACE IS STILL VERY DRY AT THE LOWER LEVELS AND TOP DOWN
SATURATION WILL TAKE A BIT LONGER TO OVERCOME.
KREIN
&&
.SHORT TERM...
354 AM CDT
TODAY THROUGH TUESDAY NIGHT...
IN THE NEAR TERM...A COMBINATION COLD FRONT/LAKE BREEZE HAS
PUSHED INLAND ACROSS NORTHERN IL TO ABOUT A RFD-DPA-CGX LINE BY
LATE LAST EVENING. COLD AIR IS QUITE SHALLOW HOWEVER...WITH AN
AMDAR AIRCRAFT ASCENT SOUNDING FROM ORD AROUND 03Z SHOWING THE TOP
OF THE INVERSION AT AROUND 1400 FT AGL (13C/55F AT 940 MB).
SOUTHWEST WINDS AROUND 30 KT ABOVE THIS INVERSION DEPICT THE
LARGER SCALE PATTERN ACROSS THE MIDWEST...WITH BROAD REGION OF
WEST-SOUTHWEST FLOW AND A SERIES OF RELATIVELY SMALL-AMPLITUDE
SHORT WAVE TROUGHS NOTED UPSTREAM OF THE FORECAST AREA IN 00Z RAOB
ANALYSIS. GUIDANCE INDICATES THIS DEEP OPPOSING FLOW WILL CAUSE
FRONT TO STALL OVERNIGHT AND BEGIN TO LIFT BACK TO THE NORTH EARLY
THIS MORNING. WITHIN THIS REGION OF SOUTHERLY FLOW
HOWEVER...MOISTURE WAS BEGINNING TO INCREASE FROM THE SOUTH AS
NOTED BY LOW-MID LEVEL CLOUDS EXPANDING NORTH ACROSS CENTRAL IL.
EXTRAPOLATION FROM GOES SATELLITE IMAGERY SUGGESTS CLOUDS WILL
EXPAND ACROSS THE CWA EARLY THIS MORNING...SUPPORTED BY MODEL
FORECAST SOUNDINGS WHICH DEPICT INCREASING RH IN THE 900-800 MB
LAYER. SOME HIGH-RES GUIDANCE MEMBERS (MAINLY THE WPC NMM) DEVELOP
SOME VERY SPOTTY QPF ACROSS PARTS OF THE CWA DURING THE LATE
MORNING HOURS FROM THIS RELATIVELY SHALLOW CLOUD LAYER...THOUGH
THE LACK OF DEEP MOISTURE ARGUES AGAINST CARRYING ANY MENTIONABLE
POP DURING THE DAY. MUCH GREATER POTENTIAL FOR PRECIPITATION
DEVELOPS THIS EVENING...AS SHORT WAVE ENERGY CURRENTLY EMERGING
FROM THE CENTRAL ROCKIES APPROACHES. GUIDANCE IS A LITTLE MIXED IN
DENOTING AREA OF GREATEST QPF/PROBABILITY...THOUGH THE BEST
FORCING INITIALLY FOCUSES ON EASTERN IOWA/NORTHWEST IL TOWARD
EVENING WITH THE STRONGEST MOISTURE TRANSPORT AND THETA-E
ADVECTION ASSOCIATED WITH 30 KT H8 FLOW RESULTING FROM THE MID-
LEVEL WAVE. THIS FLOW THEN WEAKENS AND VEERS MORE WESTERLY
OVERNIGHT...FOCUSING BETTER PRECIP POTENTIAL EASTWARD ALONG THE
FRONTAL ZONE AND MAINLY ACROSS OUR SOUTHERN CWA. WRF SOUNDINGS
INDICATE FAIRLY DECENT ELEVATED CAPE (1500+ J/KG) ACROSS THE
SOUTH/SOUTHWESTERN CWA COINCIDENT WITH THE NOSE OF THE LOW LEVEL
JET...DECREASING (200-300 J/KG) FARTHER NORTH. BEYOND MIDNIGHT
SOUNDINGS DEPICT MID-LEVEL DRYING AND CAPPING ABOVE SATURATED
LOWER LEVELS...WITH DECREASING LIFT/ELEVATED INSTABILITY FOCUSED
MAINLY ACROSS THE SOUTH/SOUTHEAST CWA. LIGHTER RAIN/DRIZZLE LIKELY
TO LINGER ACROSS THE NORTH WITHIN WEAK BUT PERSISTENT ASCENT IN
SATURATED LAYER BELOW ABOUT 750 MB.
TEMPERATURE FORECAST TODAY IS COMPLICATED BY AFOREMENTIONED
INCREASE IN CLOUD COVER...AS WELL AS CONSOLIDATION OF
WARM/STATIONARY FRONT ACROSS THE CWA IN ADVANCE OF SURFACE LOW
ACROSS THE PLAINS. A CONSIDERABLE PORTION OF THE WARM ADVECTION
OCCURS ABOVE OUR MOIST LAYER AND INVERSION THRU THE DAY...AND
WINDS ACROSS NORTHEAST ILLINOIS TAKE ON AN EASTERLY COMPONENT BY
MID-LATE AFTERNOON AS FRONTAL ZONE EVOLVES AND TIGHTENS ACROSS THE
SOUTHERN PORTION OR JUST SOUTH OF THE FORECAST AREA TONIGHT. MODEL
THERMAL FIELDS AT 950-925 MB LEVELS SUPPORT HIGHS IN THE LOW-MID
60S...WITH TEMPS LIKELY TURNING COOLER ALONG THE ILLINOIS SHORE BY
LATE AFTERNOON. SHARPENING OF WEST-EAST FRONT ACROSS CENTRAL IL/IN
TONIGHT WILL RESULT IN A CONTINUED LARGE NORTH-SOUTH TEMP
GRADIENT...LIKELY FROM THE UPPER 30S ALONG THE IL LAKE MICHIGAN
SHORE TO THE 50S ACROSS THE SOUTHERN CWA.
LITTLE CHANGE TO THIS PATTERN IS EXPECTED TUESDAY INTO
WEDNESDAY... WITH THE NEARLY STATIONARY FRONTAL BOUNDARY REMAINING
ACROSS THE SOUTH PART OR JUST SOUTH OF THE CWA AND REMAINING A
FOCUS FOR PRECIPITATION WITH A SERIES OF MINOR MID-LEVEL WAVES.
THERE IS SOME CONSENSUS IN GUIDANCE SOLUTIONS WITH A MORE
AMPLIFIED MID-LEVEL TROUGH AND ASSOCIATED SURFACE WAVE WHICH
APPROACHES TUESDAY AFTERNOON AND MOVES ACROSS THE AREA TUESDAY
NIGHT PRODUCING ANOTHER PERIOD OF HIGHER CONFIDENCE RAIN/THUNDER.
THE WEAKENING SURFACE LOW IS PROGGED TO MOVE EAST OF THE AREA
WEDNESDAY MORNING...WITH THE FRONT SAGGING FARTHER SOUTH INTO
CENTRAL/SOUTHERN IL AND INDIANA DURING THE DAY. COOL
TEMPS...CLOUDS AND PERHAPS FOG AND DRIZZLE CAN BE EXPECTED WITH
COOL NORTHEAST WINDS NORTH OF THE FRONTAL BOUNDARY WEDNESDAY.
RATZER
&&
.LONG TERM...
422 AM CDT
WEDNESDAY NIGHT THROUGH SUNDAY...
DEEP UPPER TROUGH/CLOSED LOW OVER THE WESTERN CONUS MOVES EAST
ACROSS THE ROCKIES AND OVER THE PLAINS WEDNESDAY NIGHT...WITH
SURFACE LOW PRESSURE DEVELOPING OVER THE MID-MISSOURI RIVER VALLEY
BY THURSDAY MORNING. WITH THE DEEPENING LOW OVER THE PLAINS...
INCREASING SOUTH FLOW IS INDUCED DOWNSTREAM ACROSS THE MIDWEST
WITH ASSOCIATED INCREASE IN MOISTURE TRANSPORT. THIS INCREASES THE
LIKELY HOOD OF SHOWERS AND THUNDERSTORMS AGAIN WEDNESDAY NIGHT
INTO THURSDAY AND THURSDAY EVENING AS THE SYSTEM APPROACHES. SOME
DIFFERENCES REMAIN AMONGST MODEL SOLUTIONS WITH REGARD TO THE
TIMING AND TRACK OF THE SURFACE LOW...WITH THE GFS AND GEM NOTABLY
SLOWER AND DEEPER THAN THE PAST COUPLE OF RUNS OF THE ECMWF. IN
ANY CASE...STRONG WARM/MOIST ADVECTION SPREADS ACROSS THE FORECAST
AREA WITH THE WARM FRONT LIFTING ACROSS THE CWA EARLY THURSDAY.
THURSDAY CONTINUES TO PRESENT THE POTENTIAL FOR SEVERE WEATHER IN
THE REGION AHEAD OF STRONG UPPER SYSTEM AND IN VICINITY OF SURFACE
LOW/TRIPLE POINT...ESPECIALLY WITH SLOWER GFS/GEM SOLUTIONS. GIVEN
ENERGETIC APPROACHING TROUGH AND SURFACE LOW...PRESENCE OF
WARM/POTENTIALLY UNSTABLE AIR MASS AND SUFFICIENT DEEP LAYER
SHEAR...SEVERE POTENTIAL WILL HAVE TO BE MONITORED. MUCH OF AREA
REMAINS IN SPC DAY 4 RISK.
EVEN WITH SLOWER GFS/GEM MOVEMENT OF SURFACE LOW...OCCLUDING COLD
FRONT IS EXPECTED TO MOVE THROUGH THE AREA BY EARLY FRIDAY
MORNING. DRY SLOT THEN SPREADS ACROSS THE AREA DURING THE DAY
WHILE UPPER TROUGH/LOW SLOWLY LIFTS NORTHEAST ACROSS WI AND THE
NORTHERN LAKES. THUS PRECIP POTENTIAL LOOKS TO DIMINISH
MARKEDLY...WITH DRY CONDITIONS CONTINUING SATURDAY AS WEAK HIGH
PRESSURE MOVES IN. BOTH GFS AND ECMWF BRING ANOTHER FAIRLY
AMPLIFIED UPPER TROUGH ACROSS THE NORTHERN/CENTRAL PLAINS LATE IN
THE WEEKEND...WITH ANOTHER CHANCE OF PRECIP/THUNDER LATE SUNDAY OR
SUNDAY NIGHT.
THURSDAY LOOKS TO BE THE WARMEST DAY OF THE EXTENDED PERIOD WITH
WARM FRONT LIFTING NORTH AHEAD OF THE DEEP SURFACE LOW TO OUR
WEST. AGAIN DIFFERENCES IN PLACEMENT LOWER CONFIDENCE IN
DETAILS...THOUGH MUCH OF CWA MAY BE IN THE 70S. COOLER BUT NEAR
NORMAL TEMPS FRIDAY INTO THE WEEKEND...MID 50S TO LOW 60S...WITH
LAKE BREEZE COOLING MAINLY ON SUNDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* LIGHT EAST NORTHEAST EARLY THIS AFTERNOON...INCREASING TO
AROUND 10 KT BY MID LATE AFTERNOON.
* SCATTERED LIGHT SHOWERS AND FOG TONIGHT.
* MVFR CEILINGS THIS EVENING LOWERING TO IFR TONIGHT...WITH A
PERIOD OF LIFR CEILINGS POSSIBLE TONIGHT.
RODRIGUEZ
//DISCUSSION...UPDATED 18Z...
GENERALLY QUIET CONDITIONS IN PLACE EARLY THIS AFTERNOON WITH VFR
CONDITIONS AND LIGHT WINDS. VFR CONDITIONS WILL LIKELY REMAIN IN
PLACE THIS AFTERNOON THROUGH EARLY EVENING WHILE A TREND TOWARDS A
SOUTH SOUTHEAST WIND OCCURS FOR RFD/DPA/GYY AND A TREND TOWARDS AN
EAST NORTHEAST WIND OCCURS FOR ORD/MDW. SPEEDS WILL INITIALLY BE
LIGHT OUT OF THE EAST NORTHEAST BUT WITH AN INCREASE IN SPEEDS
EXPECTED THROUGH THE AFTERNOON...WITH AROUND 10 KT EXPECTED BY
21Z. EXPECT THESE SPEEDS TO PERSIST THIS AFTERNOON INTO THE
EVENING AND POSSIBLY INCREASING ABOVE 10KT AT TIMES. A FRONTAL
BOUNDARY WITH SEVERAL MID LEVEL DISTURBANCES WILL HELP WITH PRECIP
DEVELOPMENT AND LOWERING CEILINGS TONIGHT INTO EARLY TUESDAY
MORNING. VFR CONDITIONS WILL BE REPLACED WITH MVFR THIS EVENING
AND THEN CONTINUING TO LOWER TO IFR OVERNIGHT. LOWER CONFIDENCE
WITH LIFR CEILINGS AND HAVE LEFT OUT OF THE TAF AT THIS TIME...BUT
IT DOES APPEAR TO BE POSSIBLE AT LEAST FOR A SHORT WINDOW TONIGHT.
IFR CEILINGS WILL LIKELY THEN REMAIN IN PLACE THROUGH THE REST OF
THE FORECAST PERIOD. WITH INSTABILITY REMAINING WELL SOUTH OF THE
TERMINALS TONIGHT...DONT EXPECT ANY THUNDER TONIGHT INTO TUESDAY
MORNING. HOWEVER...PERIODS OF LIGHT RAIN OR DRIZZLE WILL LIKELY BE
OBSERVED.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM HIGH CONFIDENCE WITH WIND SPEED/DIRECTION...MEDIUM
CONFIDENCE WITH EXACT TIMING OF EAST NORTHEAST WINDS AROUND 10
KT THIS AFTERNOON.
* MEDIUM HIGH CONFIDENCE WITH SHOWER/FOG TRENDS.
* HIGH CONFIDENCE FOR MVFR AND IFR CEILINGS TONIGHT...MEDIUM ON
EXACT TIMING...LOW CONFIDENCE WITH IFR POTENTIAL.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
* TUESDAY NIGHT...CHANCE OF SHRA/TSRA. IFR/LIFR. STRONG/GUSTY
NORTHEAST WINDS.
* WEDNESDAY...MAINLY DRY. IFR. GUSTY NORTHEAST WINDS.
* WEDNESDAY NIGHT...SHRA/TSRA LIKELY. IFR. EAST WINDS.
* THURSDAY AND THURSDAY NIGHT...SHRA/TSRA. IFR LIKELY. SOUTH
WINDS.
* FRIDAY...CHANCE OF SHRA. MVFR POSSIBLE. GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. WEST WINDS.
* SUNDAY...SLIGHT CHANCE OF SHRA. SOUTHEAST WINDS.
&&
.MARINE...
342 AM...A FRONTAL BOUNDARY WILL LIFT NORTH ACROSS PORTIONS OF
SOUTHERN LAKE MICHIGAN THIS MORNING BUT WILL THEN MOVE BACK SOUTH
THIS AFTERNOON...AND SOUTH OF THE LAKE BY THIS EVENING. THIS FRONT
IS THEN EXPECTED TO REMAIN GENERALLY STATIONARY JUST SOUTH OF THE
LAKE INTO THURSDAY WHEN LOW PRESSURE WILL MOVE ACROSS THE REGION.
NORTHEAST/EAST WINDS 15-25 KTS WILL PERSIST THRU THURSDAY WITH A
PERIOD OF 30KTS POSSIBLE TUESDAY INTO TUESDAY NIGHT...ESPECIALLY
ACROSS THE NORTHERN HALF/TWO THIRDS OF THE LAKE. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1250 PM CDT Mon Apr 6 2015
.UPDATE...
ISSUED AT 1035 AM CDT MON APR 6 2015
The current forecast is in good condition. A quasi stationary
front still remains over northern Illinois, while a warm front
over the central Plains will affect southern portions of the CWA
tonight into tomorrow morning. Cloud cover will remain over
Illinois for the rest of today, with a few breaks here and there.
Portions of southeast Illinois experienced scattered, light
showers this morning, with light rain reported in Lawrenceville.
Temperatures, winds, sky cover, and precipitation are currently in
check, so will leave the forecast for today as is with only minor
adjustments.
&&
.SHORT TERM...(Today)
ISSUED AT 239 AM CDT MON APR 6 2015
Latest surface analysis indicating a stationary front located over
extreme northern Illinois through northern Iowa, which is forecast
to hold to our north until tonight when it will start to edge south
across the forecast area. Meanwhile, our persistent southerly flow
has brought an increase in cloud cover to the forecast area early
this morning along with a few sprinkles being reported to our south
at Mattoon and Salem during the past hour. RAP forecast soundings
showing the depth of the moisture will not be very deep today,
roughly 3000-4000 feet, so any light rain that is able to make it to
the ground will not amount to much. Short term models do indicate a
subtle shortwave tracking east across the forecast area through
early morning which may be enough to shake out some light rain from
time to time, especially across the south and east. Had low chance
POPs going in the east and see no reason to change that, with the
better chances for showers and thunderstorms arriving by late this
afternoon across the far northwest. RAP and HRRR models also forecast
surface dew points to increase to around 50 degrees over the south
half of the area by later today, compared with upper teens to low 20
dew points this past weekend.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 239 AM CDT MON APR 6 2015
NWP models continue to show an active weather pattern from tonight
through Thursday night, with periodic rain chances. Potential for
storms will initially be limited to mainly our western counties
tonight, with the SPC marginal risk area covering west of Rushville
to Taylorville. The best chance of strong to severe storms still
looks to be Thursday afternoon/eve with the arrival of a stronger
shortwave and cold front.
A stationary front across northern Illinois will be the focus for
showers to develop tonight, once moisture levels increase and
frontogenetic forcing intensifies. The front is expected to drift
southward into central IL tonight, stalling out again roughly along
I-72 from Tuesday through Wednesday night.
Weakening low pressure will progress into western Illinois Tuesday
afternoon, with an increase of F-gen forcing and instability across
our central and northern counties. However, better potential for
strong storms will remain west of IL. Forcing for storms Wed
afternoon appears tied to shortwaves tracking over the top of low
level F-gen forcing, but severe potential appears low again late Wed
and Wed night.
While the models are indicating QPF amounts in every period this
week, there will be extended breaks in the rainfall in the wake of
individual waves that progress eastward along the frontal boundary.
Despite continued model differences in timing, we tried to highlight
the periods with the best chances for precip with likely or higher
PoPs. Right now, that includes tonight into Tuesday mainly in the
north, Wed night in the south, Thurs in the west, and Thur night in
the east.
A more substantial low along the Pacific coast will push east into
the Rockies on Wednesday, reaching northern IL Thursday night.
Impacts from that system will be felt in our area as early as Wed
night, especially closer to the front in our southern counties.
Severe potential will ramp up on Thursday afternoon as a surface low
pressure center approaches NW IL and a cold front reaches western
IL. That front will progress across IL Thur night, with support
aloft from an intensifying jet streak. Wind shear and instability
params appear favorable for rotating storms with large hail,
damaging winds and even a few tornadoes. At this point, model
consensus points toward storms affecting areas W of I-55 Thur aftn,
and east of I-55 Thurs evening.
A few showers could linger Friday morning east of I-57, but most
areas should be dry on Friday. That break from rain/storms is
expected to continue into the weekend, under surface high pressure.
The next weather disturbance could arrive later Sunday afternoon, as
the upper flow remains relatively zonal. More significant pattern
differences in the extended models are keeping confidence low on
timing, so will keep chance PoPs confined to our far western
counties Sunday for now.
Temperatures through the week will be closely tied to the
oscillation of the stationary front south then north through central
IL. We kept temps well above guidance in the southern counties until
the cold frontal passage Thursday night, while northern areas were
kept closer to normal temps after the front drifts south toward I-72
for Tuesday to Thursday. Thursday looks to be the warmest day of the
week, with cooler conditions from Friday through Sunday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1234 PM CDT MON APR 6 2015
Main issue with the beginning of the TAF period is the fluctuating
CIGs between VFR and MVFR. For PIA and BMI, have CIGs at VFR to
begin the TAF period, while SPI, DEC, and CMI have MVFR. A
quasi stationary front will move back and forth across northern
Illinois into portions of central Illinois. This front will be the
focus for some thunderstorm and shower development later this
afternoon into the evening, so have included showers with VCTS
for all TAF sites around 03Z/04Z. A warm front will also be
lifting northward towards SPI, DEC, and CMI overnight into the
very early morning hours, which may produce some stronger
thunderstorms overnight. CIG heights will decrease to IFR overnight as
sounding profiles saturate towards the surface and as the fronts
move near the terminals. Currently have IFR CIGs becoming MVFR,
and becoming scattered further west over PIA and SPI by late
tomorrow morning, with broken CIGs over the remainder of the
sites towards the end of the TAF period.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ALW
SHORT TERM...Smith
LONG TERM...Shimon
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1100 AM CDT MON APR 6 2015
.SHORT TERM...
354 AM CDT
TODAY THROUGH TUESDAY NIGHT...
IN THE NEAR TERM...A COMBINATION COLD FRONT/LAKE BREEZE HAS
PUSHED INLAND ACROSS NORTHERN IL TO ABOUT A RFD-DPA-CGX LINE BY
LATE LAST EVENING. COLD AIR IS QUITE SHALLOW HOWEVER...WITH AN
AMDAR AIRCRAFT ASCENT SOUNDING FROM ORD AROUND 03Z SHOWING THE TOP
OF THE INVERSION AT AROUND 1400 FT AGL (13C/55F AT 940 MB).
SOUTHWEST WINDS AROUND 30 KT ABOVE THIS INVERSION DEPICT THE
LARGER SCALE PATTERN ACROSS THE MIDWEST...WITH BROAD REGION OF
WEST-SOUTHWEST FLOW AND A SERIES OF RELATIVELY SMALL-AMPLITUDE
SHORT WAVE TROUGHS NOTED UPSTREAM OF THE FORECAST AREA IN 00Z RAOB
ANALYSIS. GUIDANCE INDICATES THIS DEEP OPPOSING FLOW WILL CAUSE
FRONT TO STALL OVERNIGHT AND BEGIN TO LIFT BACK TO THE NORTH EARLY
THIS MORNING. WITHIN THIS REGION OF SOUTHERLY FLOW
HOWEVER...MOISTURE WAS BEGINNING TO INCREASE FROM THE SOUTH AS
NOTED BY LOW-MID LEVEL CLOUDS EXPANDING NORTH ACROSS CENTRAL IL.
EXTRAPOLATION FROM GOES SATELLITE IMAGERY SUGGESTS CLOUDS WILL
EXPAND ACROSS THE CWA EARLY THIS MORNING...SUPPORTED BY MODEL
FORECAST SOUNDINGS WHICH DEPICT INCREASING RH IN THE 900-800 MB
LAYER. SOME HIGH-RES GUIDANCE MEMBERS (MAINLY THE WPC NMM) DEVELOP
SOME VERY SPOTTY QPF ACROSS PARTS OF THE CWA DURING THE LATE
MORNING HOURS FROM THIS RELATIVELY SHALLOW CLOUD LAYER...THOUGH
THE LACK OF DEEP MOISTURE ARGUES AGAINST CARRYING ANY MENTIONABLE
POP DURING THE DAY. MUCH GREATER POTENTIAL FOR PRECIPITATION
DEVELOPS THIS EVENING...AS SHORT WAVE ENERGY CURRENTLY EMERGING
FROM THE CENTRAL ROCKIES APPROACHES. GUIDANCE IS A LITTLE MIXED IN
DENOTING AREA OF GREATEST QPF/PROBABILITY...THOUGH THE BEST
FORCING INITIALLY FOCUSES ON EASTERN IOWA/NORTHWEST IL TOWARD
EVENING WITH THE STRONGEST MOISTURE TRANSPORT AND THETA-E
ADVECTION ASSOCIATED WITH 30 KT H8 FLOW RESULTING FROM THE MID-
LEVEL WAVE. THIS FLOW THEN WEAKENS AND VEERS MORE WESTERLY
OVERNIGHT...FOCUSING BETTER PRECIP POTENTIAL EASTWARD ALONG THE
FRONTAL ZONE AND MAINLY ACROSS OUR SOUTHERN CWA. WRF SOUNDINGS
INDICATE FAIRLY DECENT ELEVATED CAPE (1500+ J/KG) ACROSS THE
SOUTH/SOUTHWESTERN CWA COINCIDENT WITH THE NOSE OF THE LOW LEVEL
JET...DECREASING (200-300 J/KG) FARTHER NORTH. BEYOND MIDNIGHT
SOUNDINGS DEPICT MID-LEVEL DRYING AND CAPPING ABOVE SATURATED
LOWER LEVELS...WITH DECREASING LIFT/ELEVATED INSTABILITY FOCUSED
MAINLY ACROSS THE SOUTH/SOUTHEAST CWA. LIGHTER RAIN/DRIZZLE LIKELY
TO LINGER ACROSS THE NORTH WITHIN WEAK BUT PERSISTENT ASCENT IN
SATURATED LAYER BELOW ABOUT 750 MB.
TEMPERATURE FORECAST TODAY IS COMPLICATED BY AFOREMENTIONED
INCREASE IN CLOUD COVER...AS WELL AS CONSOLIDATION OF
WARM/STATIONARY FRONT ACROSS THE CWA IN ADVANCE OF SURFACE LOW
ACROSS THE PLAINS. A CONSIDERABLE PORTION OF THE WARM ADVECTION
OCCURS ABOVE OUR MOIST LAYER AND INVERSION THRU THE DAY...AND
WINDS ACROSS NORTHEAST ILLINOIS TAKE ON AN EASTERLY COMPONENT BY
MID-LATE AFTERNOON AS FRONTAL ZONE EVOLVES AND TIGHTENS ACROSS THE
SOUTHERN PORTION OR JUST SOUTH OF THE FORECAST AREA TONIGHT. MODEL
THERMAL FIELDS AT 950-925 MB LEVELS SUPPORT HIGHS IN THE LOW-MID
60S...WITH TEMPS LIKELY TURNING COOLER ALONG THE ILLINOIS SHORE BY
LATE AFTERNOON. SHARPENING OF WEST-EAST FRONT ACROSS CENTRAL IL/IN
TONIGHT WILL RESULT IN A CONTINUED LARGE NORTH-SOUTH TEMP
GRADIENT...LIKELY FROM THE UPPER 30S ALONG THE IL LAKE MICHIGAN
SHORE TO THE 50S ACROSS THE SOUTHERN CWA.
LITTLE CHANGE TO THIS PATTERN IS EXPECTED TUESDAY INTO
WEDNESDAY... WITH THE NEARLY STATIONARY FRONTAL BOUNDARY REMAINING
ACROSS THE SOUTH PART OR JUST SOUTH OF THE CWA AND REMAINING A
FOCUS FOR PRECIPITATION WITH A SERIES OF MINOR MID-LEVEL WAVES.
THERE IS SOME CONSENSUS IN GUIDANCE SOLUTIONS WITH A MORE
AMPLIFIED MID-LEVEL TROUGH AND ASSOCIATED SURFACE WAVE WHICH
APPROACHES TUESDAY AFTERNOON AND MOVES ACROSS THE AREA TUESDAY
NIGHT PRODUCING ANOTHER PERIOD OF HIGHER CONFIDENCE RAIN/THUNDER.
THE WEAKENING SURFACE LOW IS PROGGED TO MOVE EAST OF THE AREA
WEDNESDAY MORNING...WITH THE FRONT SAGGING FARTHER SOUTH INTO
CENTRAL/SOUTHERN IL AND INDIANA DURING THE DAY. COOL
TEMPS...CLOUDS AND PERHAPS FOG AND DRIZZLE CAN BE EXPECTED WITH
COOL NORTHEAST WINDS NORTH OF THE FRONTAL BOUNDARY WEDNESDAY.
RATZER
&&
.LONG TERM...
422 AM CDT
WEDNESDAY NIGHT THROUGH SUNDAY...
DEEP UPPER TROUGH/CLOSED LOW OVER THE WESTERN CONUS MOVES EAST
ACROSS THE ROCKIES AND OVER THE PLAINS WEDNESDAY NIGHT...WITH
SURFACE LOW PRESSURE DEVELOPING OVER THE MID-MISSOURI RIVER VALLEY
BY THURSDAY MORNING. WITH THE DEEPENING LOW OVER THE PLAINS...
INCREASING SOUTH FLOW IS INDUCED DOWNSTREAM ACROSS THE MIDWEST
WITH ASSOCIATED INCREASE IN MOISTURE TRANSPORT. THIS INCREASES THE
LIKELY HOOD OF SHOWERS AND THUNDERSTORMS AGAIN WEDNESDAY NIGHT
INTO THURSDAY AND THURSDAY EVENING AS THE SYSTEM APPROACHES. SOME
DIFFERENCES REMAIN AMONGST MODEL SOLUTIONS WITH REGARD TO THE
TIMING AND TRACK OF THE SURFACE LOW...WITH THE GFS AND GEM NOTABLY
SLOWER AND DEEPER THAN THE PAST COUPLE OF RUNS OF THE ECMWF. IN
ANY CASE...STRONG WARM/MOIST ADVECTION SPREADS ACROSS THE FORECAST
AREA WITH THE WARM FRONT LIFTING ACROSS THE CWA EARLY THURSDAY.
THURSDAY CONTINUES TO PRESENT THE POTENTIAL FOR SEVERE WEATHER IN
THE REGION AHEAD OF STRONG UPPER SYSTEM AND IN VICINITY OF SURFACE
LOW/TRIPLE POINT...ESPECIALLY WITH SLOWER GFS/GEM SOLUTIONS. GIVEN
ENERGETIC APPROACHING TROUGH AND SURFACE LOW...PRESENCE OF
WARM/POTENTIALLY UNSTABLE AIR MASS AND SUFFICIENT DEEP LAYER
SHEAR...SEVERE POTENTIAL WILL HAVE TO BE MONITORED. MUCH OF AREA
REMAINS IN SPC DAY 4 RISK.
EVEN WITH SLOWER GFS/GEM MOVEMENT OF SURFACE LOW...OCCLUDING COLD
FRONT IS EXPECTED TO MOVE THROUGH THE AREA BY EARLY FRIDAY
MORNING. DRY SLOT THEN SPREADS ACROSS THE AREA DURING THE DAY
WHILE UPPER TROUGH/LOW SLOWLY LIFTS NORTHEAST ACROSS WI AND THE
NORTHERN LAKES. THUS PRECIP POTENTIAL LOOKS TO DIMINISH
MARKEDLY...WITH DRY CONDITIONS CONTINUING SATURDAY AS WEAK HIGH
PRESSURE MOVES IN. BOTH GFS AND ECMWF BRING ANOTHER FAIRLY
AMPLIFIED UPPER TROUGH ACROSS THE NORTHERN/CENTRAL PLAINS LATE IN
THE WEEKEND...WITH ANOTHER CHANCE OF PRECIP/THUNDER LATE SUNDAY OR
SUNDAY NIGHT.
THURSDAY LOOKS TO BE THE WARMEST DAY OF THE EXTENDED PERIOD WITH
WARM FRONT LIFTING NORTH AHEAD OF THE DEEP SURFACE LOW TO OUR
WEST. AGAIN DIFFERENCES IN PLACEMENT LOWER CONFIDENCE IN
DETAILS...THOUGH MUCH OF CWA MAY BE IN THE 70S. COOLER BUT NEAR
NORMAL TEMPS FRIDAY INTO THE WEEKEND...MID 50S TO LOW 60S...WITH
LAKE BREEZE COOLING MAINLY ON SUNDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* WIND SHIFT/LAKE BREEZE TO EAST/NORTHEAST BY MIDDAY...INCREASING
TO AROUND 10 KT BY MID LATE AFTERNOON.
* SCATTERED SHOWERS DEVELOPING THIS EVENING.
* MVFR CIGS DEVELOPING THIS AFTERNOON...LOWERING TO IFR/LIFR EARLY
TUESDAY MORNING.
CMS/RODRIGUEZ
//DISCUSSION...UPDATED 12Z...
A FRONTAL BOUNDARY ACROSS FAR NORTHERN IL AND SOUTHERN WI WILL
REMAIN NEARLY STATIONARY THIS MORNING...THEN MOVING BACK SOUTH
THIS AFTERNOON...AIDED BY A LAKE BREEZE. SOUTHERLY WINDS UNDER 10
KTS WILL CONTINUE INTO EARLY THIS AFTERNOON WITH WINDS SHIFTING TO
THE EAST/NORTHEAST MID/LATE AFTERNOON. FAIRLY CONFIDENT THIS WILL
OCCUR...BUT TIMING AND SPECIFIC DIRECTIONS/SPEEDS WILL NEED SOME
REFINEMENT. WINDS WILL THEN REMAIN EASTERLY FOR THE REMAINDER OF
THE PERIOD AND BEGIN TO INCREASE OVERNIGHT INTO TUESDAY MORNING.
AN UPPER LEVEL WAVE WILL MOVE ACROSS THE AREA TONIGHT BRINGING A
PERIOD OF SHOWERS. CONFIDENCE REGARDING HOW WIDESPREAD THESE
BECOME AS WELL AS THE DURATION IS SOMEWHAT LOW. INSTABILITY ALSO
SUGGESTS THE POTENTIAL FOR ISOLATED TSRA BUT NOT CONFIDENT ENOUGH
TO INCLUDE IN THIS FORECAST.
5-7KFT CIGS CONTINUE TO SPREAD ACROSS THE TERMINALS THIS MORNING
WITH MVFR CIGS ACROSS PARTS OF WEST/CENTRAL IL. THESE APPEAR TO
MAKE A PUSH INTO NORTHWEST IL AND RFD THIS MORNING THEN SPREAD
INTO NORTHEAST IL THIS AFTERNOON...WHILE AT THE SAME TIME LOWER
CLOUDS MAY BE DEVELOPING AS COOLER AIR SPREADS IN FROM THE LAKE.
CIGS WILL CONTINUE TO LOWER THIS EVENING ESPECIALLY WHEN ANY
SHOWERS DEVELOP. CIGS WILL LIKELY LOWER TO IFR/LIFR OVERNIGHT
AND CONTINUE INTO TUESDAY MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH FOR WIND SHIFT TO THE EAST/NORTHEAST...MEDIUM ON EXACT
TIMING AND WITH SPEED TRENDS THROUGH THE AFTERNOON.
* MEDIUM FOR SHOWERS THIS EVENING...LOW FOR COVERAGE/DURATION.
* HIGH FOR MVFR CIGS DEVELOPING THIS AFTERNOON...MEDIUM FOR
TIMING.
* HIGH FOR IFR/LIFR CIGS DEVELOPING LATE TONIGHT/EARLY TUESDAY
MORNING...MEDIUM FOR TIMING.
CMS/RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
* TUESDAY NIGHT...CHANCE OF SHRA/TSRA. IFR/LIFR. STRONG/GUSTY
NORTHEAST WINDS.
* WEDNESDAY...MAINLY DRY. IFR. GUSTY NORTHEAST WINDS.
* WEDNESDAY NIGHT...SHRA/TSRA LIKELY. IFR. EAST WINDS.
* THURSDAY AND THURSDAY NIGHT...SHRA/TSRA. IFR LIKELY. SOUTH
WINDS.
* FRIDAY...CHANCE OF SHRA. MVFR POSSIBLE. GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. WEST WINDS.
* SUNDAY...SLIGHT CHANCE OF SHRA. SOUTHEAST WINDS.
&&
.MARINE...
342 AM...A FRONTAL BOUNDARY WILL LIFT NORTH ACROSS PORTIONS OF
SOUTHERN LAKE MICHIGAN THIS MORNING BUT WILL THEN MOVE BACK SOUTH
THIS AFTERNOON...AND SOUTH OF THE LAKE BY THIS EVENING. THIS FRONT
IS THEN EXPECTED TO REMAIN GENERALLY STATIONARY JUST SOUTH OF THE
LAKE INTO THURSDAY WHEN LOW PRESSURE WILL MOVE ACROSS THE REGION.
NORTHEAST/EAST WINDS 15-25 KTS WILL PERSIST THRU THURSDAY WITH A
PERIOD OF 30KTS POSSIBLE TUESDAY INTO TUESDAY NIGHT...ESPECIALLY
ACROSS THE NORTHERN HALF/TWO THIRDS OF THE LAKE. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1036 AM CDT Mon Apr 6 2015
.UPDATE...
ISSUED AT 1035 AM CDT MON APR 6 2015
The current forecast is in good condition. A quasi stationary
front still remains over northern Illinois, while a warm front
over the central Plains will affect southern portions of the CWA
tonight into tomorrow morning. Cloud cover will remain over
Illinois for the rest of today, with a few breaks here and there.
Portions of southeast Illinois experienced scattered, light
showers this morning, with light rain reported in Lawrenceville.
Temperatures, winds, sky cover, and precipitation are currently in
check, so will leave the forecast for today as is with only minor
adjustments.
&&
.SHORT TERM...(Today)
ISSUED AT 239 AM CDT MON APR 6 2015
Latest surface analysis indicating a stationary front located over
extreme northern Illinois through northern Iowa, which is forecast
to hold to our north until tonight when it will start to edge south
across the forecast area. Meanwhile, our persistent southerly flow
has brought an increase in cloud cover to the forecast area early
this morning along with a few sprinkles being reported to our south
at Mattoon and Salem during the past hour. RAP forecast soundings
showing the depth of the moisture will not be very deep today,
roughly 3000-4000 feet, so any light rain that is able to make it to
the ground will not amount to much. Short term models do indicate a
subtle shortwave tracking east across the forecast area through
early morning which may be enough to shake out some light rain from
time to time, especially across the south and east. Had low chance
POPs going in the east and see no reason to change that, with the
better chances for showers and thunderstorms arriving by late this
afternoon across the far northwest. RAP and HRRR models also forecast
surface dew points to increase to around 50 degrees over the south
half of the area by later today, compared with upper teens to low 20
dew points this past weekend.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 239 AM CDT MON APR 6 2015
NWP models continue to show an active weather pattern from tonight
through Thursday night, with periodic rain chances. Potential for
storms will initially be limited to mainly our western counties
tonight, with the SPC marginal risk area covering west of Rushville
to Taylorville. The best chance of strong to severe storms still
looks to be Thursday afternoon/eve with the arrival of a stronger
shortwave and cold front.
A stationary front across northern Illinois will be the focus for
showers to develop tonight, once moisture levels increase and
frontogenetic forcing intensifies. The front is expected to drift
southward into central IL tonight, stalling out again roughly along
I-72 from Tuesday through Wednesday night.
Weakening low pressure will progress into western Illinois Tuesday
afternoon, with an increase of F-gen forcing and instability across
our central and northern counties. However, better potential for
strong storms will remain west of IL. Forcing for storms Wed
afternoon appears tied to shortwaves tracking over the top of low
level F-gen forcing, but severe potential appears low again late Wed
and Wed night.
While the models are indicating QPF amounts in every period this
week, there will be extended breaks in the rainfall in the wake of
individual waves that progress eastward along the frontal boundary.
Despite continued model differences in timing, we tried to highlight
the periods with the best chances for precip with likely or higher
PoPs. Right now, that includes tonight into Tuesday mainly in the
north, Wed night in the south, Thurs in the west, and Thur night in
the east.
A more substantial low along the Pacific coast will push east into
the Rockies on Wednesday, reaching northern IL Thursday night.
Impacts from that system will be felt in our area as early as Wed
night, especially closer to the front in our southern counties.
Severe potential will ramp up on Thursday afternoon as a surface low
pressure center approaches NW IL and a cold front reaches western
IL. That front will progress across IL Thur night, with support
aloft from an intensifying jet streak. Wind shear and instability
params appear favorable for rotating storms with large hail,
damaging winds and even a few tornadoes. At this point, model
consensus points toward storms affecting areas W of I-55 Thur aftn,
and east of I-55 Thurs evening.
A few showers could linger Friday morning east of I-57, but most
areas should be dry on Friday. That break from rain/storms is
expected to continue into the weekend, under surface high pressure.
The next weather disturbance could arrive later Sunday afternoon, as
the upper flow remains relatively zonal. More significant pattern
differences in the extended models are keeping confidence low on
timing, so will keep chance PoPs confined to our far western
counties Sunday for now.
Temperatures through the week will be closely tied to the
oscillation of the stationary front south then north through central
IL. We kept temps well above guidance in the southern counties until
the cold frontal passage Thursday night, while northern areas were
kept closer to normal temps after the front drifts south toward I-72
for Tuesday to Thursday. Thursday looks to be the warmest day of the
week, with cooler conditions from Friday through Sunday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 605 AM CDT MON APR 6 2015
MVFR cigs are expected to expand north and cover most of our
area today with IFR cigs expected tonight with scattered showers
and isolated thunderstorms. Low level moisture continues to
increase from south to north with cigs lowering to 2500-3500
feet at SPI and DEC and would expect our other sites to see
the same happen this morning and then continue with MVFR cigs
this afternoon. The threat for precip increases tonight with
cigs lowering to at least tempo IFR in -SHRA with VCTS.
Surface winds today will remain out of the south at 10 to 15 kts
with winds backing a bit more into a southeasterly direction
tonight at 8 to 13 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ALW
SHORT TERM...Smith
LONG TERM...Shimon
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
640 AM CDT MON APR 6 2015
.SHORT TERM...
354 AM CDT
TODAY THROUGH TUESDAY NIGHT...
IN THE NEAR TERM...A COMBINATION COLD FRONT/LAKE BREEZE HAS
PUSHED INLAND ACROSS NORTHERN IL TO ABOUT A RFD-DPA-CGX LINE BY
LATE LAST EVENING. COLD AIR IS QUITE SHALLOW HOWEVER...WITH AN
AMDAR AIRCRAFT ASCENT SOUNDING FROM ORD AROUND 03Z SHOWING THE TOP
OF THE INVERSION AT AROUND 1400 FT AGL (13C/55F AT 940 MB).
SOUTHWEST WINDS AROUND 30 KT ABOVE THIS INVERSION DEPICT THE
LARGER SCALE PATTERN ACROSS THE MIDWEST...WITH BROAD REGION OF
WEST-SOUTHWEST FLOW AND A SERIES OF RELATIVELY SMALL-AMPLITUDE
SHORT WAVE TROUGHS NOTED UPSTREAM OF THE FORECAST AREA IN 00Z RAOB
ANALYSIS. GUIDANCE INDICATES THIS DEEP OPPOSING FLOW WILL CAUSE
FRONT TO STALL OVERNIGHT AND BEGIN TO LIFT BACK TO THE NORTH EARLY
THIS MORNING. WITHIN THIS REGION OF SOUTHERLY FLOW
HOWEVER...MOISTURE WAS BEGINNING TO INCREASE FROM THE SOUTH AS
NOTED BY LOW-MID LEVEL CLOUDS EXPANDING NORTH ACROSS CENTRAL IL.
EXTRAPOLATION FROM GOES SATELLITE IMAGERY SUGGESTS CLOUDS WILL
EXPAND ACROSS THE CWA EARLY THIS MORNING...SUPPORTED BY MODEL
FORECAST SOUNDINGS WHICH DEPICT INCREASING RH IN THE 900-800 MB
LAYER. SOME HIGH-RES GUIDANCE MEMBERS (MAINLY THE WPC NMM) DEVELOP
SOME VERY SPOTTY QPF ACROSS PARTS OF THE CWA DURING THE LATE
MORNING HOURS FROM THIS RELATIVELY SHALLOW CLOUD LAYER...THOUGH
THE LACK OF DEEP MOISTURE ARGUES AGAINST CARRYING ANY MENTIONABLE
POP DURING THE DAY. MUCH GREATER POTENTIAL FOR PRECIPITATION
DEVELOPS THIS EVENING...AS SHORT WAVE ENERGY CURRENTLY EMERGING
FROM THE CENTRAL ROCKIES APPROACHES. GUIDANCE IS A LITTLE MIXED IN
DENOTING AREA OF GREATEST QPF/PROBABILITY...THOUGH THE BEST
FORCING INITIALLY FOCUSES ON EASTERN IOWA/NORTHWEST IL TOWARD
EVENING WITH THE STRONGEST MOISTURE TRANSPORT AND THETA-E
ADVECTION ASSOCIATED WITH 30 KT H8 FLOW RESULTING FROM THE MID-
LEVEL WAVE. THIS FLOW THEN WEAKENS AND VEERS MORE WESTERLY
OVERNIGHT...FOCUSING BETTER PRECIP POTENTIAL EASTWARD ALONG THE
FRONTAL ZONE AND MAINLY ACROSS OUR SOUTHERN CWA. WRF SOUNDINGS
INDICATE FAIRLY DECENT ELEVATED CAPE (1500+ J/KG) ACROSS THE
SOUTH/SOUTHWESTERN CWA COINCIDENT WITH THE NOSE OF THE LOW LEVEL
JET...DECREASING (200-300 J/KG) FARTHER NORTH. BEYOND MIDNIGHT
SOUNDINGS DEPICT MID-LEVEL DRYING AND CAPPING ABOVE SATURATED
LOWER LEVELS...WITH DECREASING LIFT/ELEVATED INSTABILITY FOCUSED
MAINLY ACROSS THE SOUTH/SOUTHEAST CWA. LIGHTER RAIN/DRIZZLE LIKELY
TO LINGER ACROSS THE NORTH WITHIN WEAK BUT PERSISTENT ASCENT IN
SATURATED LAYER BELOW ABOUT 750 MB.
TEMPERATURE FORECAST TODAY IS COMPLICATED BY AFOREMENTIONED
INCREASE IN CLOUD COVER...AS WELL AS CONSOLIDATION OF
WARM/STATIONARY FRONT ACROSS THE CWA IN ADVANCE OF SURFACE LOW
ACROSS THE PLAINS. A CONSIDERABLE PORTION OF THE WARM ADVECTION
OCCURS ABOVE OUR MOIST LAYER AND INVERSION THRU THE DAY...AND
WINDS ACROSS NORTHEAST ILLINOIS TAKE ON AN EASTERLY COMPONENT BY
MID-LATE AFTERNOON AS FRONTAL ZONE EVOLVES AND TIGHTENS ACROSS THE
SOUTHERN PORTION OR JUST SOUTH OF THE FORECAST AREA TONIGHT. MODEL
THERMAL FIELDS AT 950-925 MB LEVELS SUPPORT HIGHS IN THE LOW-MID
60S...WITH TEMPS LIKELY TURNING COOLER ALONG THE ILLINOIS SHORE BY
LATE AFTERNOON. SHARPENING OF WEST-EAST FRONT ACROSS CENTRAL IL/IN
TONIGHT WILL RESULT IN A CONTINUED LARGE NORTH-SOUTH TEMP
GRADIENT...LIKELY FROM THE UPPER 30S ALONG THE IL LAKE MICHIGAN
SHORE TO THE 50S ACROSS THE SOUTHERN CWA.
LITTLE CHANGE TO THIS PATTERN IS EXPECTED TUESDAY INTO
WEDNESDAY... WITH THE NEARLY STATIONARY FRONTAL BOUNDARY REMAINING
ACROSS THE SOUTH PART OR JUST SOUTH OF THE CWA AND REMAINING A
FOCUS FOR PRECIPITATION WITH A SERIES OF MINOR MID-LEVEL WAVES.
THERE IS SOME CONSENSUS IN GUIDANCE SOLUTIONS WITH A MORE
AMPLIFIED MID-LEVEL TROUGH AND ASSOCIATED SURFACE WAVE WHICH
APPROACHES TUESDAY AFTERNOON AND MOVES ACROSS THE AREA TUESDAY
NIGHT PRODUCING ANOTHER PERIOD OF HIGHER CONFIDENCE RAIN/THUNDER.
THE WEAKENING SURFACE LOW IS PROGGED TO MOVE EAST OF THE AREA
WEDNESDAY MORNING...WITH THE FRONT SAGGING FARTHER SOUTH INTO
CENTRAL/SOUTHERN IL AND INDIANA DURING THE DAY. COOL
TEMPS...CLOUDS AND PERHAPS FOG AND DRIZZLE CAN BE EXPECTED WITH
COOL NORTHEAST WINDS NORTH OF THE FRONTAL BOUNDARY WEDNESDAY.
RATZER
&&
.LONG TERM...
422 AM CDT
WEDNESDAY NIGHT THROUGH SUNDAY...
DEEP UPPER TROUGH/CLOSED LOW OVER THE WESTERN CONUS MOVES EAST
ACROSS THE ROCKIES AND OVER THE PLAINS WEDNESDAY NIGHT...WITH
SURFACE LOW PRESSURE DEVELOPING OVER THE MID-MISSOURI RIVER VALLEY
BY THURSDAY MORNING. WITH THE DEEPENING LOW OVER THE PLAINS...
INCREASING SOUTH FLOW IS INDUCED DOWNSTREAM ACROSS THE MIDWEST
WITH ASSOCIATED INCREASE IN MOISTURE TRANSPORT. THIS INCREASES THE
LIKELY HOOD OF SHOWERS AND THUNDERSTORMS AGAIN WEDNESDAY NIGHT
INTO THURSDAY AND THURSDAY EVENING AS THE SYSTEM APPROACHES. SOME
DIFFERENCES REMAIN AMONGST MODEL SOLUTIONS WITH REGARD TO THE
TIMING AND TRACK OF THE SURFACE LOW...WITH THE GFS AND GEM NOTABLY
SLOWER AND DEEPER THAN THE PAST COUPLE OF RUNS OF THE ECMWF. IN
ANY CASE...STRONG WARM/MOIST ADVECTION SPREADS ACROSS THE FORECAST
AREA WITH THE WARM FRONT LIFTING ACROSS THE CWA EARLY THURSDAY.
THURSDAY CONTINUES TO PRESENT THE POTENTIAL FOR SEVERE WEATHER IN
THE REGION AHEAD OF STRONG UPPER SYSTEM AND IN VICINITY OF SURFACE
LOW/TRIPLE POINT...ESPECIALLY WITH SLOWER GFS/GEM SOLUTIONS. GIVEN
ENERGETIC APPROACHING TROUGH AND SURFACE LOW...PRESENCE OF
WARM/POTENTIALLY UNSTABLE AIR MASS AND SUFFICIENT DEEP LAYER
SHEAR...SEVERE POTENTIAL WILL HAVE TO BE MONITORED. MUCH OF AREA
REMAINS IN SPC DAY 4 RISK.
EVEN WITH SLOWER GFS/GEM MOVEMENT OF SURFACE LOW...OCCLUDING COLD
FRONT IS EXPECTED TO MOVE THROUGH THE AREA BY EARLY FRIDAY
MORNING. DRY SLOT THEN SPREADS ACROSS THE AREA DURING THE DAY
WHILE UPPER TROUGH/LOW SLOWLY LIFTS NORTHEAST ACROSS WI AND THE
NORTHERN LAKES. THUS PRECIP POTENTIAL LOOKS TO DIMINISH
MARKEDLY...WITH DRY CONDITIONS CONTINUING SATURDAY AS WEAK HIGH
PRESSURE MOVES IN. BOTH GFS AND ECMWF BRING ANOTHER FAIRLY
AMPLIFIED UPPER TROUGH ACROSS THE NORTHERN/CENTRAL PLAINS LATE IN
THE WEEKEND...WITH ANOTHER CHANCE OF PRECIP/THUNDER LATE SUNDAY OR
SUNDAY NIGHT.
THURSDAY LOOKS TO BE THE WARMEST DAY OF THE EXTENDED PERIOD WITH
WARM FRONT LIFTING NORTH AHEAD OF THE DEEP SURFACE LOW TO OUR
WEST. AGAIN DIFFERENCES IN PLACEMENT LOWER CONFIDENCE IN
DETAILS...THOUGH MUCH OF CWA MAY BE IN THE 70S. COOLER BUT NEAR
NORMAL TEMPS FRIDAY INTO THE WEEKEND...MID 50S TO LOW 60S...WITH
LAKE BREEZE COOLING MAINLY ON SUNDAY.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* WIND SHIFT/LAKE BREEZE TO EAST/NORTHEAST MID/LATE AFTERNOON.
* SCATTERED SHOWERS DEVELOPING THIS EVENING.
* MVFR CIGS DEVELOPING THIS AFTERNOON...LOWERING TO IFR/LIFR EARLY
TUESDAY MORNING. CMS
//DISCUSSION...UPDATED 12Z...
A FRONTAL BOUNDARY ACROSS FAR NORTHERN IL AND SOUTHERN WI WILL
REMAIN NEARLY STATIONARY THIS MORNING...THEN MOVING BACK SOUTH
THIS AFTERNOON...AIDED BY A LAKE BREEZE. SOUTHERLY WINDS UNDER 10
KTS WILL CONTINUE INTO EARLY THIS AFTERNOON WITH WINDS SHIFTING TO
THE EAST/NORTHEAST MID/LATE AFTERNOON. FAIRLY CONFIDENT THIS WILL
OCCUR...BUT TIMING AND SPECIFIC DIRECTIONS/SPEEDS WILL NEED SOME
REFINEMENT. WINDS WILL THEN REMAIN EASTERLY FOR THE REMAINDER OF
THE PERIOD AND BEGIN TO INCREASE OVERNIGHT INTO TUESDAY MORNING.
AN UPPER LEVEL WAVE WILL MOVE ACROSS THE AREA TONIGHT BRINGING A
PERIOD OF SHOWERS. CONFIDENCE REGARDING HOW WIDESPREAD THESE
BECOME AS WELL AS THE DURATION IS SOMEWHAT LOW. INSTABILITY ALSO
SUGGESTS THE POTENTIAL FOR ISOLATED TSRA BUT NOT CONFIDENT ENOUGH
TO INCLUDE IN THIS FORECAST.
5-7KFT CIGS CONTINUE TO SPREAD ACROSS THE TERMINALS THIS MORNING
WITH MVFR CIGS ACROSS PARTS OF WEST/CENTRAL IL. THESE APPEAR TO
MAKE A PUSH INTO NORTHWEST IL AND RFD THIS MORNING THEN SPREAD
INTO NORTHEAST IL THIS AFTERNOON...WHILE AT THE SAME TIME LOWER
CLOUDS MAY BE DEVELOPING AS COOLER AIR SPREADS IN FROM THE LAKE.
CIGS WILL CONTINUE TO LOWER THIS EVENING ESPECIALLY WHEN ANY
SHOWERS DEVELOP. CIGS WILL LIKELY LOWER TO IFR/LIFR OVERNIGHT
AND CONTINUE INTO TUESDAY MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH FOR WIND SHIFT TO THE EAST/NORTHEAST MID/LATE AFTERNOON...
MEDIUM FOR TIMING...LOW FOR SPEEDS.
* MEDIUM FOR SHOWERS THIS EVENING...LOW FOR COVERAGE/DURATION.
* HIGH FOR MVFR CIGS DEVELOPING THIS AFTERNOON...MEDIUM FOR
TIMING.
* HIGH FOR IFR/LIFR CIGS DEVELOPING LATE TONIGHT/EARLY TUESDAY
MORNING...MEDIUM FOR TIMING. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
* TUESDAY NIGHT...CHANCE OF SHRA/TSRA. IFR/LIFR. STRONG/GUSTY
NORTHEAST WINDS.
* WEDNESDAY...MAINLY DRY. IFR. GUSTY NORTHEAST WINDS.
* WEDNESDAY NIGHT...SHRA/TSRA LIKELY. IFR. EAST WINDS.
* THURSDAY AND THURSDAY NIGHT...SHRA/TSRA. IFR LIKELY. SOUTH
WINDS.
* FRIDAY...CHANCE OF SHRA. MVFR POSSIBLE. GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. WEST WINDS.
* SUNDAY...SLIGHT CHANCE OF SHRA. SOUTHEAST WINDS.
&&
.MARINE...
342 AM...A FRONTAL BOUNDARY WILL LIFT NORTH ACROSS PORTIONS OF
SOUTHERN LAKE MICHIGAN THIS MORNING BUT WILL THEN MOVE BACK SOUTH
THIS AFTERNOON...AND SOUTH OF THE LAKE BY THIS EVENING. THIS FRONT
IS THEN EXPECTED TO REMAIN GENERALLY STATIONARY JUST SOUTH OF THE
LAKE INTO THURSDAY WHEN LOW PRESSURE WILL MOVE ACROSS THE REGION.
NORTHEAST/EAST WINDS 15-25 KTS WILL PERSIST THRU THURSDAY WITH A
PERIOD OF 30KTS POSSIBLE TUESDAY INTO TUESDAY NIGHT...ESPECIALLY
ACROSS THE NORTHERN HALF/TWO THIRDS OF THE LAKE. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
614 AM CDT Mon Apr 6 2015
.SHORT TERM...(Today)
ISSUED AT 239 AM CDT MON APR 6 2015
Latest surface analysis indicating a stationary front located over
extreme northern Illinois through northern Iowa, which is forecast
to hold to our north until tonight when it will start to edge south
across the forecast area. Meanwhile, our persistent southerly flow
has brought an increase in cloud cover to the forecast area early
this morning along with a few sprinkles being reported to our south
at Mattoon and Salem during the past hour. RAP forecast soundings
showing the depth of the moisture will not be very deep today,
roughly 3000-4000 feet, so any light rain that is able to make it to
the ground will not amount to much. Short term models do indicate a
subtle shortwave tracking east across the forecast area through
early morning which may be enough to shake out some light rain from
time to time, especially across the south and east. Had low chance
POPs going in the east and see no reason to change that, with the
better chances for showers and thunderstorms arriving by late this
afternoon across the far northwest. RAP and HRRR models also forecast
surface dew points to increase to around 50 degrees over the south
half of the area by later today, compared with upper teens to low 20
dew points this past weekend.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 239 AM CDT MON APR 6 2015
NWP models continue to show an active weather pattern from tonight
through Thursday night, with periodic rain chances. Potential for
storms will initially be limited to mainly our western counties
tonight, with the SPC marginal risk area covering west of Rushville
to Taylorville. The best chance of strong to severe storms still
looks to be Thursday afternoon/eve with the arrival of a stronger
shortwave and cold front.
A stationary front across northern Illinois will be the focus for
showers to develop tonight, once moisture levels increase and
frontogenetic forcing intensifies. The front is expected to drift
southward into central IL tonight, stalling out again roughly along
I-72 from Tuesday through Wednesday night.
Weakening low pressure will progress into western Illinois Tuesday
afternoon, with an increase of F-gen forcing and instability across
our central and northern counties. However, better potential for
strong storms will remain west of IL. Forcing for storms Wed
afternoon appears tied to shortwaves tracking over the top of low
level F-gen forcing, but severe potential appears low again late Wed
and Wed night.
While the models are indicating QPF amounts in every period this
week, there will be extended breaks in the rainfall in the wake of
individual waves that progress eastward along the frontal boundary.
Despite continued model differences in timing, we tried to highlight
the periods with the best chances for precip with likely or higher
PoPs. Right now, that includes tonight into Tuesday mainly in the
north, Wed night in the south, Thurs in the west, and Thur night in
the east.
A more substantial low along the Pacific coast will push east into
the Rockies on Wednesday, reaching northern IL Thursday night.
Impacts from that system will be felt in our area as early as Wed
night, especially closer to the front in our southern counties.
Severe potential will ramp up on Thursday afternoon as a surface low
pressure center approaches NW IL and a cold front reaches western
IL. That front will progress across IL Thur night, with support
aloft from an intensifying jet streak. Wind shear and instability
params appear favorable for rotating storms with large hail,
damaging winds and even a few tornadoes. At this point, model
consensus points toward storms affecting areas W of I-55 Thur aftn,
and east of I-55 Thurs evening.
A few showers could linger Friday morning east of I-57, but most
areas should be dry on Friday. That break from rain/storms is
expected to continue into the weekend, under surface high pressure.
The next weather disturbance could arrive later Sunday afternoon, as
the upper flow remains relatively zonal. More significant pattern
differences in the extended models are keeping confidence low on
timing, so will keep chance PoPs confined to our far western
counties Sunday for now.
Temperatures through the week will be closely tied to the
oscillation of the stationary front south then north through central
IL. We kept temps well above guidance in the southern counties until
the cold frontal passage Thursday night, while northern areas were
kept closer to normal temps after the front drifts south toward I-72
for Tuesday to Thursday. Thursday looks to be the warmest day of the
week, with cooler conditions from Friday through Sunday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 605 AM CDT MON APR 6 2015
MVFR cigs are expected to expand north and cover most of our
area today with IFR cigs expected tonight with scattered showers
and isolated thunderstorms. Low level moisture continues to
increase from south to north with cigs lowering to 2500-3500
feet at SPI and DEC and would expect our other sites to see
the same happen this morning and then continue with MVFR cigs
this afternoon. The threat for precip increases tonight with
cigs lowering to at least tempo IFR in -SHRA with VCTS.
Surface winds today will remain out of the south at 10 to 15 kts
with winds backing a bit more into a southeasterly direction
tonight at 8 to 13 kts.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...Shimon
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
342 AM CDT MON APR 6 2015
.SHORT TERM...
247 PM CDT
THROUGH TUESDAY...
PRIMARY CONCERN IN THE SHORT TERM REVOLVES AROUND LAKE ENHANCED
FRONTAL POSITIONING AND SUBSEQUENT TEMPS THROUGH TOMORROW
EVENING...THEN SHOWER AND THUNDERSTORM CHANCES MONDAY NIGHT.
WEAKER GRADIENT IN THE VICINITY OF THE STATIONARY FRONT OVER
SOUTHERN WISCONSIN HAS ALLOWED THE LAKE TO TAKE OVER WITH WELL
DEVELOPED LAKE BREEZE SEEN PLOWING INLAND ON THE MKE TERMINAL
DOPPLER RADAR. LAKE BREEZE WILL BE ENCOUNTERING A BRISK SOUTHWEST
WIND THIS AFTERNOON OVER NE IL...BUT WITH TIME THE REMAINDER OF THE
AFTERNOON THE GRADIENT WILL RELAX AND SHOULD ALLOW THE LAKE BREEZE
TO PENETRATE MORE DEEPLY INTO NE IL EARLY THIS EVENING. GUIDANCE IN
PRETTY GOOD AGREEMENT ON THE LAKE BREEZE DISSIPATING THIS EVENING
AND SOUTHERLY SYNOPTIC GRADIENT FLOW ALLOWING MILD AIR TO MOVE BACK
NORTHEAST TO THE LAKE FRONT OVERNIGHT. THE RESULT WILL BE TRICKY AND
ATYPICAL DIURNAL TEMP TRENDS IN NE IL THROUGH TONIGHT.
MONDAY LOOKS TO LARGELY BE A REPEAT OF TODAY EXCEPT WITH LOW LEVEL
MOISTURE RETURNING WILL SEE SKIES CLOUD UP AND LIKELY KEEP TEMPS A
FEW DEGREES COOLER THAN TODAY. WINDS SHOULD BE LIGHTER MONDAY AS
WELL...SO EVEN THOUGH FRONT WILL START OUT OVER SOUTHERN WI EARLY IN
THE DAY...LAKE WILL LIKELY HAVE ITS SAY AGAIN SENDING A LAKE BREEZE
ENHANCED FRONT SOUTHWEST INTO NE IL DURING THE AFTERNOON RESULTING
IN DROPPING TEMPS LATE IN THE DAY. SYNOPTIC FRONT WILL SETTLE
SOUTHWARD INTO NORTHERN ILLINOIS MONDAY EVENING AS SFC CYCLOGENESIS
TAKES PLACE OVER THE CENTRAL PLAINS IN RESPONSE DEVELOPING WESTERN
TROUGH AND LEAD LOW AMPLITUDE SHORTWAVE EJECTING NORTHEAST OUT OF
THE DIGGING WESTERN TROUGH.
SHOWERS AND THUNDERSTORMS WILL DEVELOP TO OUR WEST OVER THE CORN
BELT LATE MONDAY AND SPILL EASTWARD INTO OUR CWA LATER MONDAY
EVENING INTO THE OVERNIGHT HOURS FED BY STRONG LOW LEVEL THETA-E
ADVECTION ASSOCIATED WITH 40KT+ LOW LEVEL JET. COULD BE ENOUGH
ELEVATED INSTABILITY TO SUPPORT SOME SMALL HAIL AND HEAVY RAIN WITH
THE MORE ROBUST CONVECTION MONDAY NIGHT.
IZZI
&&
.LONG TERM...
247 PM CDT
TUESDAY NIGHT THROUGH SUNDAY...
IN THE WAKE OF MONDAY NIGHT`S CONVECTION A CLASSIC SPRING I-80 FRONT
WILL BE LEFT BEHIND OVER THE CWA WITH A SHALLOW LAKE ENHANCED COLD
AIR MASS TO THE NORTH OF THE BOUNDARY AND SPRING WARMTH TO THE SOUTH
OVER FAR SOUTHERN CWA. FAIRLY STRONG NORTHEAST WINDS OFF THE LAKE
WILL FURTHER SHARPEN THE ALREADY SHALLOW FRONTAL INVERSION TO THE
NORTH OF THE BOUNDARY. THE RETURNING LOW LEVEL MOISTURE MONDAY NIGHT
AND SHALLOW COLD WEDGE NOSING BENEATH IT WILL SET UP A CLASSIC
CHICAGO "SPRING" LOW STRATUS AND FOG SITUATION TUESDAY AND LIKELY
LINGERING THROUGH THE DAY WEDNESDAY. FOG...POSSIBLY DENSE...LOOKS
LIKELY BEHIND THE FRONT...ESPECIALLY NEAR THE LAKE WITH DRIZZLE AND
LOW CEILINGS LIKES TO CAUSE TEMPS TO HOLD IN THE 40S AND PROBABLY
LOWER/MID 40S AT THAT NORTH OF THE FRONT WITH UPPER 30S POSSIBLE
NEAR THE LAKE. PRECIP TUES SHOULD BE CONFINED TO MAINLY DRIZZLE OR
VERY LIGHT RAIN...WITH BETTER CHANCES OF MEASURABLE SHOWERS ENDING
OVER THE SE CWA IN THE MORNING. LATER IN THE DAY SOME GUIDANCE DOES
SHOW ANOTHER SHORTWAVE MOVING TOWARD WESTERN CWA WHICH COULD LEAD TO
AN UPTICK IN SHOWERS LATE IN THE DAY INTO TUES EVENING. VERY
WARM/MOIST AIR ABOVE THE SHALLOW INVERSION COULD STILL ALLOW FOR
ISOLATED THUNDERSTORMS TO DEVELOP BEFORE THIS IMPULSE MOVES EAST OF
THE REGION LATE TUES NIGHT OR WEDNESDAY.
THE I-80 FRONT IS PROGGED TO SETTLE SLOWLY SOUTH TUES NIGHT AND
LARGELY BE SOUTH OF OUR CWA WEDNESDAY WITH SUBTLE SHORTWAVE RIDGING
ALOFT LIKELY LEADING TO A PRIMARILY DRY DAY ACROSS THE CWA. DRIZZLE
AND FOG WILL REMAIN A POSSIBILITY NEAR THE LAKE
WEDNESDAY...ESPECIALLY IN THE MORNING.
WESTERN TROUGH IS FORECAST TO REMAIN FAIRLY PROGRESSIVE AND MOVE OUT
INTO THE PLAINS LATER IN THE WEEK. STILL SOME SIZABLE SPREAD IN THE
MEDIUM RANGE MODELS WITH RESPECT TO HOW FAST THE SYSTEM KICKS OUT
AND RESULTANT TIMING OF OUR SENSIBLE WEATHER CHANGES LATE IN THE
WEEK. THE GFS REMAINS ON THE FAST END OF THE GUIDANCE ENVELOPE...BUT
GIVEN THE PROGGED STRENGTH OF THIS SYSTEM AND FACT IT IS FORECAST TO
MAINTAIN A DEEP CLOSED CIRCULATION ALOFT AM INCLINED TO BELIEVE IT
WILL BE A SLOWER MOVING SYSTEM CLOSER TO THE ECMWF SOLUTION. AT THIS
DISTANCE IT IS SILLY TO START GETTING TRYING TO TALK ABOUT DETAILS
AND BEST WE CAN SAY AT THIS POINT IS THAT SHOWERS/STORMS APPEAR
LIKELY WHEN IT MOVES THROUGH LATE IN THE WEEK AND IF CURRENT
NORTHERLY TRACK VERIFIES THE WARM FRONT SHOULD BE DRAWN BACK
NORTHWARD ACROSS THE AREA PLACING OUR CWA BACK IN THE HUMID WARM
SECTOR WITH THE MILLION DOLLAR QUESTION BEING WHEN. SYNOPTICALLY
PATTERN LOOKS REMARKABLY SIMALAR TO PREVIOUS MULTI-DAY SIGNIFICANT
SEVERE WEATHER OUTBREAKS. AT THIS DISTANCE THE BETTER CHANCES OF
SEVERE WEATHER CERTAINLY LOOK TO LIE WEST OF OUR CWA...ESPECIALLY IF
SLOWER SOLUTIONS PAN OUR AND SYSTEM IS WEAKENING AND OCCLUDING BY
TIME IT ARRIVES HERE. NONE THE LESS LATER THIS WEEK DOES BEAR
WATCHING BECAUSE A FASTER SOLUTION VERIFYING WOULD PLACE PORTIONS OF
OUR CWA MUCH CLOSER TO THE GREATER SEVERE THREAT.
IN THE WAKE OF THIS SYSTEM LOOK FOR A BRIEF COOL DOWN BEFORE ANOTHER
WESTERN TROUGH DEVELOPS AND PUSHES EASTWARD WITH A WARM UP POSSIBLE
NEXT WEEKEND IN ADVANCE OF IT.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* WIND SHIFT/LAKE BREEZE TO EAST/NORTHEAST MID/LATE AFTERNOON.
* SCATTERED SHOWERS DEVELOPING THIS EVENING.
* MVFR CIGS DEVELOPING THIS AFTERNOON...LOWERING TO IFR/LIFR EARLY
TUESDAY MORNING. CMS
//DISCUSSION...UPDATED 06Z...
SEVERAL FORECAST CONCERNS THIS PERIOD...MAINLY THIS AFTERNOON
INTO TONIGHT. FRONTAL BOUNDARY REMAINS FROM RFD TO ORD EARLY THIS
MORNING AND IS EXPECTED TO LIFT BACK NORTH OVER THE NEXT FEW HRS
WITH WINDS TURNING BACK SOUTH/SOUTHWEST AT ORD/DPA/RFD. SPEEDS
SHOULD REMAIN JUST UNDER 10KTS FOR MUCH OF THIS MORNING. THIS
FRONTAL BOUNDARY WILL MOVE BACK SOUTHWEST THIS AFTERNOON SHIFTING
WINDS BACK TO THE EAST/NORTHEAST. HIGH CONFIDENCE THIS WILL OCCUR
BUT ONLY MEDIUM FOR TIMING. SPEEDS MAY INITIALLY BE UNDER 10KTS
BUT WILL LIKELY INCREASE INTO THIS EVENING. WINDS WILL THEN REMAIN
EAST/NORTHEAST FOR THE REMAINDER OF THE PERIOD.
LARGE AREA OF 5-6 KFT CLOUDS SPREADING NORTH AND WILL ARRIVE
ACROSS THE TERMINALS BEFORE SUNRISE THIS MORNING. LOW LEVEL
MOISTURE CONTINUES TO SPREAD ACROSS THE REGION WITH CIGS ALREADY
LOWERING TO MVFR ACROSS PARTS OF SOUTHERN IA AND MO. THESE LOWER
CIGS WILL LIKELY SPREAD INTO RFD FIRST THEN ACROSS THE REST OF THE
TERMINALS THIS AFTERNOON. HOWEVER...ADDITIONAL LOWER CLOUDS MAY
FORM AS COLDER AIR SPREADS IN FROM THE LAKE AFTER WINDS SHIFT
EASTERLY. THUS FAIRLY CONFIDENT CIGS WILL BE TRENDING LOWER THIS
AFTERNOON AND ESPECIALLY THIS EVENING AND OVERNIGHT. CIGS COULD
END UP EVEN LOWER THAN CURRENTLY ADVERTISED.
SCATTERED SHOWERS ARE EXPECTED TO DEVELOP THIS EVENING AS AN
UPPER WAVE ARRIVES. MOST GUIDANCE SHOWS A RELATIVELY SHORT TIME
PERIOD IN THE MID/LATE EVENING FOR BEST POTENTIAL. AFTER
MIDNIGHT APPEARS BETTER CHANCE FOR DRIZZLE. LATER FORECASTS WILL
NEED TO MONITOR TRENDS AND MAKE ADJUSTMENTS BUT MAINTAINED
PREVAILING PRECIP THIS EVENING. COULD ALSO BE SOME THUNDERSTORMS...
ESPECIALLY SOUTH OF THE TERMINALS. CONFIDENCE LOW ENOUGH TO KEEP
MENTION OUT OF THE TERMINALS WITH THIS FORECAST. CMS
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH FOR WIND SHIFT TO THE EAST/NORTHEAST MID/LATE AFTERNOON...
MEDIUM FOR TIMIMG...LOW FOR SPEEDS.
* MEDIUM FOR SHOWERS THIS EVENING...LOW FOR COVERAGE/DURATION.
* HIGH FOR MVFR CIGS DEVELOPING THIS AFTERNOON...MEDIUM FOR
TIMING.
* HIGH FOR IFR/LIFR CIGS DEVELOPING LATE TONIGHT/EARLY TUESDAY
MORNING...MEDIUM FOR TIMING. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...SHRA/TSRA. IFR/LIFR. NORTHEAST WINDS.
WEDNESDAY...IFR/LIFR. CHANCE OF DRIZZLE. EAST WINDS.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...SHRA/TSRA. IFR/LIFR. EAST
WINDS.
FRIDAY...CHANCE OF SHRA. MVFR POSSIBLE. SOUTHWEST WINDS.
SATURDAY...DRY/VFR. GUSTY WEST WINDS.
BEACHLER
&&
.MARINE...
342 AM...A FRONTAL BOUNDARY WILL LIFT NORTH ACROSS PORTIONS OF
SOUTHERN LAKE MICHIGAN THIS MORNING BUT WILL THEN MOVE BACK SOUTH
THIS AFTERNOON...AND SOUTH OF THE LAKE BY THIS EVENING. THIS FRONT
IS THEN EXPECTED TO REMAIN GENERALLY STATIONARY JUST SOUTH OF THE
LAKE INTO THURSDAY WHEN LOW PRESSURE WILL MOVE ACROSS THE REGION.
NORTHEAST/EAST WINDS 15-25 KTS WILL PERSIST THRU THURSDAY WITH A
PERIOD OF 30KTS POSSIBLE TUESDAY INTO TUESDAY NIGHT...ESPECIALLY
ACROSS THE NORTHERN HALF/TWO THIRDS OF THE LAKE. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
240 AM CDT Mon Apr 6 2015
.SHORT TERM...(Today)
ISSUED AT 239 AM CDT MON APR 6 2015
Latest surface analysis indicating a stationary front located over
extreme northern Illinois through northern Iowa, which is forecast
to hold to our north until tonight when it will start to edge south
across the forecast area. Meanwhile, our persistent southerly flow
has brought an increase in cloud cover to the forecast area early
this morning along with a few sprinkles being reported to our south
at Mattoon and Salem during the past hour. RAP forecast soundings
showing the depth of the moisture will not be very deep today,
roughly 3000-4000 feet, so any light rain that is able to make it to
the ground will not amount to much. Short term models do indicate a
subtle shortwave tracking east across the forecast area through
early morning which may be enough to shake out some light rain from
time to time, especially across the south and east. Had low chance
POPs going in the east and see no reason to change that, with the
better chances for showers and thunderstorms arriving by late this
afternoon across the far northwest. RAP and HRRR models also forecast
surface dew points to increase to around 50 degrees over the south
half of the area by later today, compared with upper teens to low 20
dew points this past weekend.
&&
.LONG TERM...(Tonight through Sunday)
ISSUED AT 239 AM CDT MON APR 6 2015
NWP models continue to show an active weather pattern from tonight
through Thursday night, with periodic rain chances. Potential for
storms will initially be limited to mainly our western counties
tonight, with the SPC marginal risk area covering west of Rushville
to Taylorville. The best chance of strong to severe storms still
looks to be Thursday afternoon/eve with the arrival of a stronger
shortwave and cold front.
A stationary front across northern Illinois will be the focus for
showers to develop tonight, once moisture levels increase and
frontogenetic forcing intensifies. The front is expected to drift
southward into central IL tonight, stalling out again roughly along
I-72 from Tuesday through Wednesday night.
Weakening low pressure will progress into western Illinois Tuesday
afternoon, with an increase of F-gen forcing and instability across
our central and northern counties. However, better potential for
strong storms will remain west of IL. Forcing for storms Wed
afternoon appears tied to shortwaves tracking over the top of low
level F-gen forcing, but severe potential appears low again late Wed
and Wed night.
While the models are indicating QPF amounts in every period this
week, there will be extended breaks in the rainfall in the wake of
individual waves that progress eastward along the frontal boundary.
Despite continued model differences in timing, we tried to highlight
the periods with the best chances for precip with likely or higher
PoPs. Right now, that includes tonight into Tuesday mainly in the
north, Wed night in the south, Thurs in the west, and Thur night in
the east.
A more substantial low along the Pacific coast will push east into
the Rockies on Wednesday, reaching northern IL Thursday night.
Impacts from that system will be felt in our area as early as Wed
night, especially closer to the front in our southern counties.
Severe potential will ramp up on Thursday afternoon as a surface low
pressure center approaches NW IL and a cold front reaches western
IL. That front will progress across IL Thur night, with support
aloft from an intensifying jet streak. Wind shear and instability
params appear favorable for rotating storms with large hail,
damaging winds and even a few tornadoes. At this point, model
consensus points toward storms affecting areas W of I-55 Thur aftn,
and east of I-55 Thurs evening.
A few showers could linger Friday morning east of I-57, but most
areas should be dry on Friday. That break from rain/storms is
expected to continue into the weekend, under surface high pressure.
The next weather disturbance could arrive later Sunday afternoon, as
the upper flow remains relatively zonal. More significant pattern
differences in the extended models are keeping confidence low on
timing, so will keep chance PoPs confined to our far western
counties Sunday for now.
Temperatures through the week will be closely tied to the
oscillation of the stationary front south then north through central
IL. We kept temps well above guidance in the southern counties until
the cold frontal passage Thursday night, while northern areas were
kept closer to normal temps after the front drifts south toward I-72
for Tuesday to Thursday. Thursday looks to be the warmest day of the
week, with cooler conditions from Friday through Sunday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1145 PM CDT SUN APR 5 2015
Cigs around 5kft have already advected into the area and will be
effecting all TAF sites by 06z. Observations show cigs below 3kft
located in MO and based on HiRes models and Bufkit data, these
lower cigs are expected to effect all TAF sites during the morning
hours, starting at SPI and DEC at 12z, then CMI by 13z, then PIA
and BMI by 14z. These MVFR cigs will continue during the morning and
continue into the afternoon hours. As the warm front sets up and
the low level jet strengthens over the area, pcpn will begin to
break out across the north and then slowly slide south during the
evening hours. PIA and BMI will see pcpn first and cigs will
further drop to just above 1kft. Similar conditions will be seen
at SPI, DEC, and CMI after PIA and BMI. The showers will likely
continue through the evening hours. Unsure on convection
potential, but believe it is possible along the front, so have
included VCTS at all sites. Winds will be southerly and then
become more southeasterly during the evening as the warm front
becomes more established.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...Shimon
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1145 PM EDT TUE APR 7 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 257 PM EDT TUE APR 7 2015
A FRONT WILL REMAIN IN THE AREA THROUGH THURSDAY...KEEPING CHANCES
FOR SHOWERS AND THUNDERSTORMS IN THE FORECAST. HIGH PRESSURE WILL
PROVIDE SOME DRY CONDITIONS FRIDAY AFTERNOON THROUGH SUNDAY. ANOTHER
FRONT WILL BRING MORE CHANCES FOR RAIN EARLY NEXT WEEK. TEMPERATURES
WILL BE NEAR TO ABOVE AVERAGE FOR MOST OF THE PERIOD.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 906 PM EDT TUE APR 7 2015
WILL LOWER POPS ESPECIALLY IN THE EVENING HOURS TO SLIGHT CHANCE
PER RADAR TRENDS AND HRRR REFLECTIVITY PROGS. ADDITIONALLY...WILL
HAVE TO LOWER TEMPERATURES SIGNIFICANTLY OVER THE FAR NORTH AS THE
FRONT MAKES SLOW SOUTHWARD PROGRESS. WILL BE A SIGNIFICANT
TEMPERATURE SPREAD ACROSS THE AREA OWING TO THE FRONT. PREVIOUS
DISCUSSION FOLLOWS.
ISSUED AT 257 PM EDT TUE APR 7 2015
LOOKS LIKE THE BULK OF AN AREA OF SHOWERS AND THUNDERSTORMS WILL
REMAIN SOUTH OF THE FORECAST AREA THIS AFTERNOON AS IT HEADS TOWARD
BETTER INSTABILITY. HOWEVER THE FAR SOUTHERN FORECAST AREA WILL
STILL SEE THE THREAT FOR SOME HEAVY RAIN AND SMALL HAIL. RAIN WILL
BE MORE SCATTERED ACROSS CENTRAL SECTIONS WITH ONLY LOW CHANCES FAR
NORTH.
BY THE START OF THE TONIGHT PERIOD...MOST OF THE RAIN SHOULD BE OFF
TO THE SOUTH IN THE MORE UNSTABLE AIR. WITH LITTLE ORGANIZATION TO
SUSTAIN CONVECTION...ONLY WENT LOW CHANCE POPS THIS EVENING.
MODELS HINT AT ANOTHER UPPER IMPULSE MOVING IN OVERNIGHT...AND A
FRONTAL BOUNDARY WILL BE ACROSS NORTHERN SECTIONS OF THE AREA.
HOWEVER AM NOT CONFIDENT PRECIPITATION WILL BE WIDESPREAD WITH LOW
LEVEL JET POINTING TO THE SOUTHEAST OF THE AREA. THUS ONLY WENT HIGH
END CHANCE CATEGORY POPS OVERNIGHT. ANY STORM WILL HAVE THE
POTENTIAL TO PRODUCE HEAVY RAIN.
FOR LOW TEMPERATURES STUCK WITH A BLEND OF MODELS GIVEN EXPECTED
CLOUDS AND THE UNCERTAINTY OF EXACTLY WHERE FRONT ACROSS THE NORTH
WILL END UP.
&&
.SHORT TERM.../WEDNESDAY THROUGH FRIDAY/
ISSUED AT 257 PM EDT TUE APR 7 2015
FOCUS IS ON CHANCES FOR RAIN THROUGH THE PERIOD. MODELS ARE CLOSE
ENOUGH TO USE A BLEND FOR MOST ITEMS...ALTHOUGH CONFIDENCE IN THE
DETAILS IS RELATIVELY LOW.
UPPER IMPULSE THAT WILL BRING THE HIGHER CHANCE POPS TUESDAY NIGHT
WILL BE EXITING THE AREA EARLY WEDNESDAY. CONTINUED HIGH CHANCE
CATEGORY POPS IN THE MORNING. DURING THE AFTERNOON THE FRONTAL
BOUNDARY SHOULD LIFT OFF TO THE NORTH OF THE AREA...AND THERE WILL
BE NO ORGANIZED FORCING. LOWERED POPS A BIT IN THE AFTERNOON /STILL
CHANCE CATEGORY/.
POTENTIAL OF UPPER WAVES TO TRIGGER ADDITIONAL CONVECTION CONTINUES
WEDNESDAY NIGHT INTO THURSDAY...BEFORE THE MAIN COLD FRONT MOVES IN
THURSDAY EVENING. CONFIDENCE IS LOW IN TIMING OF THE WAVES AND
LOCATION OF THE STORMS /SOME OF WHICH WILL DEPEND ON BOUNDARIES FROM
PREVIOUS STORMS/.
FOR NOW WENT CHANCE POPS WEDNESDAY EVENING AND LIKELY POPS NORTH
OVERNIGHT WEDNESDAY NIGHT ACROSS THE NORTH /CLOSER TO THE OLD
FRONT/. ON THURSDAY MOST MODELS SHOW RAIN AT SOME POINT DURING THE
DAY ACROSS MOST AREAS SO JUST WENT LIKELY POPS ALL DAY /EVEN THOUGH
THERE WILL LIKELY BE DRY PERIODS/.
MODELS DIFFER ON SPEED OF COLD FRONT BUT LOOKS LIKE IT SHOULD MOVE
THROUGH MAINLY DURING THE EVENING AND EARLY OVERNIGHT. WENT LIKELY
TO CATEGORICAL POPS GIVEN PLENTIFUL MOISTURE AND GOOD FORCING WITH
THE FRONT. SEVERE WEATHER DEFINITELY A POSSIBILITY DEPENDENT ON HOW
MUCH INSTABILITY IS ABLE TO BUILD BEFORE THE FRONT ARRIVES.
KEPT SOME SLIGHT CHANCE POPS EARLY FRIDAY TO ACCOUNT FOR ANY
LINGERING RAIN LEFT BEHIND. OTHERWISE FRIDAY SHOULD BE DRY WITH THE
DRIER AIR MOVING IN.
FOR TEMPERATURES THROUGH THE PERIOD GENERALLY STUCK WITH A MODEL
BLEND DUE TO THE UNCERTAINTIES IN RAINFALL TIMING AND COVERAGE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
ISSUED AT 245 PM EDT TUE APR 7 2015
THE LONG TERM WILL START OUT DRY AND COOL FOR THE WEEKEND AND THEN
BECOME WET EARLY NEXT WEEK.
MODELS MOVE AN AREA OF HIGH PRESSURE ACROSS INDIANA SATURDAY AND TO
SOUTHERN NEW ENGLAND SUNDAY. AN AREA OF LOW PRESSURE WILL DEVELOP
OVER THE SOUTHERN AND CENTRAL PLAINS SUNDAY AND MOVE INTO THE MIDDLE
MISSISSIPPI VALLEY MONDAY AND INTO THE GREAT LAKES BY TUESDAY. THIS
LOW PRESSURE SYSTEM WILL BRING A GOOD CHANCE OF SHOWERS AND A FEW
THUNDERSTORMS BEGINNING SUNDAY NIGHT AND CONTINUING THE REST OF THE
LONG TERM. MODELS MOVE A COLD FRONT ACROSS OUR REGION ON DAY 7 AND
DRY WEATHER SHOULD AGAIN BE THE RULE BY THE MIDDLE OF NEXT WEEK.
LOWS WILL BE IN THE UPPER 30S AND LOWER 40S FRIDAY NIGHT...THE 40S
SATURDAY NIGHT AND 50S SUNDAY NIGHT AND MONDAY. HIGHS WILL BE IN
THE UPPER 50S TO MIDDLE 60S SATURDAY...UPPER 60S AND LOWER 70S
SUNDAY AND MONDAY AND IN THE 60S TUESDAY. ALL AND ALL WENT CLOSE TO
A MOS BLEND ON TEMPERATURES.
&&
.AVIATION /DISCUSSION FOR THE 080600 TAFS/...
ISSUED AT 1106 PM EDT TUE APR 7 2015
POOR FLYING CONDITIONS EXPECTED THIS TAF PERIOD.
A WARM FRONT OVER CENTRAL INDIANA IS EXPECTED TO LIFT NORTH
ACROSS THE STATE REACHING NORTHERN INDIANA BY THURSDAY AFTERNOON.
TIME HEIGHTS SHOW PLENTIFUL LOW LEVEL MOISTURE AVAILABLE OVERNIGHT
AND EARLY ON WEDNESDAY AS THE FRONT PASSES NORTH. WITH THE
POSITION OF THE WARM FRONT BEING A FAVORABLE AREA FOR FOG
DEVELOPMENT OVERNIGHT...HAVE REDUCED CIGS OVERNIGHT TO IFR
CONDITIONS.
CONVECTION DEVELOPING OVER WESTERN MISSOURI SHOULD CONTINUE TO
PROPAGATE NORTHEAST ALONG I-70...JUST SOUTH OF THE WARM FRONTAL
BOUNDARY. GIVEN THIS...WILL BRING FORWARD THE VCTS WINDOW TO THE
EARLY TO MID MORNING.
WITH MORNING CONVECTION EXPECTED...ATMOS SHOULD BE A LITTLE WORKED
OVER BY AFTERNOON AND HAVE REMOVED VCTS MENTION FOR THAT TIME.
MODELS SUGGEST ANOTHER WAVE TO PUSH ACROSS THE AREA LATE WEDNESDAY
NIGHT...WITH PLENTIFUL MOISTURE AND FORCING IN PLACE...ANOTHER
ROUND OF PRECIP IS EXPECTED.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50/NIELD
SHORT TERM...50
LONG TERM...JH
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSINDIANAPOLIS
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1026 PM EDT TUE APR 7 2015
.UPDATE...
AVIATION SECTION UPDATED.
&&
.SYNOPSIS...
ISSUED AT 257 PM EDT TUE APR 7 2015
A FRONT WILL REMAIN IN THE AREA THROUGH THURSDAY...KEEPING CHANCES
FOR SHOWERS AND THUNDERSTORMS IN THE FORECAST. HIGH PRESSURE WILL
PROVIDE SOME DRY CONDITIONS FRIDAY AFTERNOON THROUGH SUNDAY. ANOTHER
FRONT WILL BRING MORE CHANCES FOR RAIN EARLY NEXT WEEK. TEMPERATURES
WILL BE NEAR TO ABOVE AVERAGE FOR MOST OF THE PERIOD.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 906 PM EDT TUE APR 7 2015
WILL LOWER POPS ESPECIALLY IN THE EVENING HOURS TO SLIGHT CHANCE
PER RADAR TRENDS AND HRRR REFLECTIVITY PROGS. ADDITIONALLY...WILL
HAVE TO LOWER TEMPERATURES SIGNIFICANTLY OVER THE FAR NORTH AS THE
FRONT MAKES SLOW SOUTHWARD PROGRESS. WILL BE A SIGNIFICANT
TEMPERATURE SPREAD ACROSS THE AREA OWING TO THE FRONT. PREVIOUS
DISCUSSION FOLLOWS.
ISSUED AT 257 PM EDT TUE APR 7 2015
LOOKS LIKE THE BULK OF AN AREA OF SHOWERS AND THUNDERSTORMS WILL
REMAIN SOUTH OF THE FORECAST AREA THIS AFTERNOON AS IT HEADS TOWARD
BETTER INSTABILITY. HOWEVER THE FAR SOUTHERN FORECAST AREA WILL
STILL SEE THE THREAT FOR SOME HEAVY RAIN AND SMALL HAIL. RAIN WILL
BE MORE SCATTERED ACROSS CENTRAL SECTIONS WITH ONLY LOW CHANCES FAR
NORTH.
BY THE START OF THE TONIGHT PERIOD...MOST OF THE RAIN SHOULD BE OFF
TO THE SOUTH IN THE MORE UNSTABLE AIR. WITH LITTLE ORGANIZATION TO
SUSTAIN CONVECTION...ONLY WENT LOW CHANCE POPS THIS EVENING.
MODELS HINT AT ANOTHER UPPER IMPULSE MOVING IN OVERNIGHT...AND A
FRONTAL BOUNDARY WILL BE ACROSS NORTHERN SECTIONS OF THE AREA.
HOWEVER AM NOT CONFIDENT PRECIPITATION WILL BE WIDESPREAD WITH LOW
LEVEL JET POINTING TO THE SOUTHEAST OF THE AREA. THUS ONLY WENT HIGH
END CHANCE CATEGORY POPS OVERNIGHT. ANY STORM WILL HAVE THE
POTENTIAL TO PRODUCE HEAVY RAIN.
FOR LOW TEMPERATURES STUCK WITH A BLEND OF MODELS GIVEN EXPECTED
CLOUDS AND THE UNCERTAINTY OF EXACTLY WHERE FRONT ACROSS THE NORTH
WILL END UP.
&&
.SHORT TERM.../WEDNESDAY THROUGH FRIDAY/
ISSUED AT 257 PM EDT TUE APR 7 2015
FOCUS IS ON CHANCES FOR RAIN THROUGH THE PERIOD. MODELS ARE CLOSE
ENOUGH TO USE A BLEND FOR MOST ITEMS...ALTHOUGH CONFIDENCE IN THE
DETAILS IS RELATIVELY LOW.
UPPER IMPULSE THAT WILL BRING THE HIGHER CHANCE POPS TUESDAY NIGHT
WILL BE EXITING THE AREA EARLY WEDNESDAY. CONTINUED HIGH CHANCE
CATEGORY POPS IN THE MORNING. DURING THE AFTERNOON THE FRONTAL
BOUNDARY SHOULD LIFT OFF TO THE NORTH OF THE AREA...AND THERE WILL
BE NO ORGANIZED FORCING. LOWERED POPS A BIT IN THE AFTERNOON /STILL
CHANCE CATEGORY/.
POTENTIAL OF UPPER WAVES TO TRIGGER ADDITIONAL CONVECTION CONTINUES
WEDNESDAY NIGHT INTO THURSDAY...BEFORE THE MAIN COLD FRONT MOVES IN
THURSDAY EVENING. CONFIDENCE IS LOW IN TIMING OF THE WAVES AND
LOCATION OF THE STORMS /SOME OF WHICH WILL DEPEND ON BOUNDARIES FROM
PREVIOUS STORMS/.
FOR NOW WENT CHANCE POPS WEDNESDAY EVENING AND LIKELY POPS NORTH
OVERNIGHT WEDNESDAY NIGHT ACROSS THE NORTH /CLOSER TO THE OLD
FRONT/. ON THURSDAY MOST MODELS SHOW RAIN AT SOME POINT DURING THE
DAY ACROSS MOST AREAS SO JUST WENT LIKELY POPS ALL DAY /EVEN THOUGH
THERE WILL LIKELY BE DRY PERIODS/.
MODELS DIFFER ON SPEED OF COLD FRONT BUT LOOKS LIKE IT SHOULD MOVE
THROUGH MAINLY DURING THE EVENING AND EARLY OVERNIGHT. WENT LIKELY
TO CATEGORICAL POPS GIVEN PLENTIFUL MOISTURE AND GOOD FORCING WITH
THE FRONT. SEVERE WEATHER DEFINITELY A POSSIBILITY DEPENDENT ON HOW
MUCH INSTABILITY IS ABLE TO BUILD BEFORE THE FRONT ARRIVES.
KEPT SOME SLIGHT CHANCE POPS EARLY FRIDAY TO ACCOUNT FOR ANY
LINGERING RAIN LEFT BEHIND. OTHERWISE FRIDAY SHOULD BE DRY WITH THE
DRIER AIR MOVING IN.
FOR TEMPERATURES THROUGH THE PERIOD GENERALLY STUCK WITH A MODEL
BLEND DUE TO THE UNCERTAINTIES IN RAINFALL TIMING AND COVERAGE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
ISSUED AT 245 PM EDT TUE APR 7 2015
THE LONG TERM WILL START OUT DRY AND COOL FOR THE WEEKEND AND THEN
BECOME WET EARLY NEXT WEEK.
MODELS MOVE AN AREA OF HIGH PRESSURE ACROSS INDIANA SATURDAY AND TO
SOUTHERN NEW ENGLAND SUNDAY. AN AREA OF LOW PRESSURE WILL DEVELOP
OVER THE SOUTHERN AND CENTRAL PLAINS SUNDAY AND MOVE INTO THE MIDDLE
MISSISSIPPI VALLEY MONDAY AND INTO THE GREAT LAKES BY TUESDAY. THIS
LOW PRESSURE SYSTEM WILL BRING A GOOD CHANCE OF SHOWERS AND A FEW
THUNDERSTORMS BEGINNING SUNDAY NIGHT AND CONTINUING THE REST OF THE
LONG TERM. MODELS MOVE A COLD FRONT ACROSS OUR REGION ON DAY 7 AND
DRY WEATHER SHOULD AGAIN BE THE RULE BY THE MIDDLE OF NEXT WEEK.
LOWS WILL BE IN THE UPPER 30S AND LOWER 40S FRIDAY NIGHT...THE 40S
SATURDAY NIGHT AND 50S SUNDAY NIGHT AND MONDAY. HIGHS WILL BE IN
THE UPPER 50S TO MIDDLE 60S SATURDAY...UPPER 60S AND LOWER 70S
SUNDAY AND MONDAY AND IN THE 60S TUESDAY. ALL AND ALL WENT CLOSE TO
A MOS BLEND ON TEMPERATURES.
&&
.AVIATION /DISCUSSION FOR THE 080300 IND TAF UPDATE/...
IFR CONDITIONS LIKELY TO CONTINUE AS LOW CLOUD HAD DEVELOPED AMID
COOLING. SOME BREAKS SEEN VIA IR IMAGES ACROSS WESTERN INDIANA
WILL BE SHORT LIVED AS LOW CLOUD IS EXPECTED TO PERSIST OVERNIGHT
AMID COOLING AND DEW POINT DEPRESSIONS NEAR SATURATION.
PREVIOUS DISCUSSION BELOW
/DISCUSSION FOR THE 080000Z TAFS/...
ISSUED AT 704 PM EDT TUE APR 7 2015
DETERIORATING FLYING CONDITIONS EXPECTED THIS TAF PERIOD.
A WARM FRONT OVER SOUTHERN INDIANA IS EXPECTED TO LIFT NORTH
ACROSS THE STATE REACHING NORTHERN INDIANA BY THURSDAY AFTERNOON.
TIME HEIGHTS SHOW PLENTIFUL LOW LEVEL MOISTURE AVAILABLE OVERNIGHT
AND EARLY ON WEDNESDAY AS THE FRONT PASSES NORTH. WITH THE
POSITION OF THE WARM FRONT BEING A FAVORABLE AREA FOR FOG
DEVELOPMENT OVERNIGHT...HAVE REDUCED CIGS OVERNIGHT TO IFR
CONDITIONS.
AS HEATING RESUMES ON WEDNESDAY AND THE WARM FRONT LIFTS FARTHER
NORTH...THE TAF SITES SHOULD RESIDE IN THE THE WARM SECTOR.
HOWEVER FORECAST SOUNDINGS REVEAL FAVORABLE LAPSE RATES FOR
CONVECTION WITH ATTAINABLE CONVECTIVE TEMPS. THUS HAVE MENTIONED
VCTS FOR NOW UNTIL MORE PRECISE TIMING IS POSSIBLE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50/NIELD
SHORT TERM...50
LONG TERM...JH
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSINDIANAPOLIS
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
906 PM EDT TUE APR 7 2015
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 257 PM EDT TUE APR 7 2015
A FRONT WILL REMAIN IN THE AREA THROUGH THURSDAY...KEEPING CHANCES
FOR SHOWERS AND THUNDERSTORMS IN THE FORECAST. HIGH PRESSURE WILL
PROVIDE SOME DRY CONDITIONS FRIDAY AFTERNOON THROUGH SUNDAY. ANOTHER
FRONT WILL BRING MORE CHANCES FOR RAIN EARLY NEXT WEEK. TEMPERATURES
WILL BE NEAR TO ABOVE AVERAGE FOR MOST OF THE PERIOD.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 906 PM EDT TUE APR 7 2015
WILL LOWER POPS ESPECIALLY IN THE EVENING HOURS TO SLIGHT CHANCE
PER RADAR TRENDS AND HRRR REFLECTIVITY PROGS. ADDITIONALLY...WILL
HAVE TO LOWER TEMPERATURES SIGNIFICANTLY OVER THE FAR NORTH AS THE
FRONT MAKES SLOW SOUTHWARD PROGRESS. WILL BE A SIGNIFICANT
TEMPERATURE SPREAD ACROSS THE AREA OWING TO THE FRONT. PREVIOUS
DISCUSSION FOLLOWS.
ISSUED AT 257 PM EDT TUE APR 7 2015
LOOKS LIKE THE BULK OF AN AREA OF SHOWERS AND THUNDERSTORMS WILL
REMAIN SOUTH OF THE FORECAST AREA THIS AFTERNOON AS IT HEADS TOWARD
BETTER INSTABILITY. HOWEVER THE FAR SOUTHERN FORECAST AREA WILL
STILL SEE THE THREAT FOR SOME HEAVY RAIN AND SMALL HAIL. RAIN WILL
BE MORE SCATTERED ACROSS CENTRAL SECTIONS WITH ONLY LOW CHANCES FAR
NORTH.
BY THE START OF THE TONIGHT PERIOD...MOST OF THE RAIN SHOULD BE OFF
TO THE SOUTH IN THE MORE UNSTABLE AIR. WITH LITTLE ORGANIZATION TO
SUSTAIN CONVECTION...ONLY WENT LOW CHANCE POPS THIS EVENING.
MODELS HINT AT ANOTHER UPPER IMPULSE MOVING IN OVERNIGHT...AND A
FRONTAL BOUNDARY WILL BE ACROSS NORTHERN SECTIONS OF THE AREA.
HOWEVER AM NOT CONFIDENT PRECIPITATION WILL BE WIDESPREAD WITH LOW
LEVEL JET POINTING TO THE SOUTHEAST OF THE AREA. THUS ONLY WENT HIGH
END CHANCE CATEGORY POPS OVERNIGHT. ANY STORM WILL HAVE THE
POTENTIAL TO PRODUCE HEAVY RAIN.
FOR LOW TEMPERATURES STUCK WITH A BLEND OF MODELS GIVEN EXPECTED
CLOUDS AND THE UNCERTAINTY OF EXACTLY WHERE FRONT ACROSS THE NORTH
WILL END UP.
&&
.SHORT TERM.../WEDNESDAY THROUGH FRIDAY/
ISSUED AT 257 PM EDT TUE APR 7 2015
FOCUS IS ON CHANCES FOR RAIN THROUGH THE PERIOD. MODELS ARE CLOSE
ENOUGH TO USE A BLEND FOR MOST ITEMS...ALTHOUGH CONFIDENCE IN THE
DETAILS IS RELATIVELY LOW.
UPPER IMPULSE THAT WILL BRING THE HIGHER CHANCE POPS TUESDAY NIGHT
WILL BE EXITING THE AREA EARLY WEDNESDAY. CONTINUED HIGH CHANCE
CATEGORY POPS IN THE MORNING. DURING THE AFTERNOON THE FRONTAL
BOUNDARY SHOULD LIFT OFF TO THE NORTH OF THE AREA...AND THERE WILL
BE NO ORGANIZED FORCING. LOWERED POPS A BIT IN THE AFTERNOON /STILL
CHANCE CATEGORY/.
POTENTIAL OF UPPER WAVES TO TRIGGER ADDITIONAL CONVECTION CONTINUES
WEDNESDAY NIGHT INTO THURSDAY...BEFORE THE MAIN COLD FRONT MOVES IN
THURSDAY EVENING. CONFIDENCE IS LOW IN TIMING OF THE WAVES AND
LOCATION OF THE STORMS /SOME OF WHICH WILL DEPEND ON BOUNDARIES FROM
PREVIOUS STORMS/.
FOR NOW WENT CHANCE POPS WEDNESDAY EVENING AND LIKELY POPS NORTH
OVERNIGHT WEDNESDAY NIGHT ACROSS THE NORTH /CLOSER TO THE OLD
FRONT/. ON THURSDAY MOST MODELS SHOW RAIN AT SOME POINT DURING THE
DAY ACROSS MOST AREAS SO JUST WENT LIKELY POPS ALL DAY /EVEN THOUGH
THERE WILL LIKELY BE DRY PERIODS/.
MODELS DIFFER ON SPEED OF COLD FRONT BUT LOOKS LIKE IT SHOULD MOVE
THROUGH MAINLY DURING THE EVENING AND EARLY OVERNIGHT. WENT LIKELY
TO CATEGORICAL POPS GIVEN PLENTIFUL MOISTURE AND GOOD FORCING WITH
THE FRONT. SEVERE WEATHER DEFINITELY A POSSIBILITY DEPENDENT ON HOW
MUCH INSTABILITY IS ABLE TO BUILD BEFORE THE FRONT ARRIVES.
KEPT SOME SLIGHT CHANCE POPS EARLY FRIDAY TO ACCOUNT FOR ANY
LINGERING RAIN LEFT BEHIND. OTHERWISE FRIDAY SHOULD BE DRY WITH THE
DRIER AIR MOVING IN.
FOR TEMPERATURES THROUGH THE PERIOD GENERALLY STUCK WITH A MODEL
BLEND DUE TO THE UNCERTAINTIES IN RAINFALL TIMING AND COVERAGE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
ISSUED AT 245 PM EDT TUE APR 7 2015
THE LONG TERM WILL START OUT DRY AND COOL FOR THE WEEKEND AND THEN
BECOME WET EARLY NEXT WEEK.
MODELS MOVE AN AREA OF HIGH PRESSURE ACROSS INDIANA SATURDAY AND TO
SOUTHERN NEW ENGLAND SUNDAY. AN AREA OF LOW PRESSURE WILL DEVELOP
OVER THE SOUTHERN AND CENTRAL PLAINS SUNDAY AND MOVE INTO THE MIDDLE
MISSISSIPPI VALLEY MONDAY AND INTO THE GREAT LAKES BY TUESDAY. THIS
LOW PRESSURE SYSTEM WILL BRING A GOOD CHANCE OF SHOWERS AND A FEW
THUNDERSTORMS BEGINNING SUNDAY NIGHT AND CONTINUING THE REST OF THE
LONG TERM. MODELS MOVE A COLD FRONT ACROSS OUR REGION ON DAY 7 AND
DRY WEATHER SHOULD AGAIN BE THE RULE BY THE MIDDLE OF NEXT WEEK.
LOWS WILL BE IN THE UPPER 30S AND LOWER 40S FRIDAY NIGHT...THE 40S
SATURDAY NIGHT AND 50S SUNDAY NIGHT AND MONDAY. HIGHS WILL BE IN
THE UPPER 50S TO MIDDLE 60S SATURDAY...UPPER 60S AND LOWER 70S
SUNDAY AND MONDAY AND IN THE 60S TUESDAY. ALL AND ALL WENT CLOSE TO
A MOS BLEND ON TEMPERATURES.
&&
.AVIATION /DISCUSSION FOR THE 070000Z TAFS/...
ISSUED AT 704 PM EDT TUE APR 7 2015
DETERIORATING FLYING CONDITIONS EXPECTED THIS TAF PERIOD.
A WARM FRONT OVER SOUTHERN INDIANA IS EXPECTED TO LIFT NORTH
ACROSS THE STATE REACHING NORTHERN INDIANA BY THURSDAY AFTERNOON.
TIME HEIGHTS SHOW PLENTIFUL LOW LEVEL MOISTURE AVAILABLE OVERNIGHT
AND EARLY ON WEDNESDAY AS THE FRONT PASSES NORTH. WITH THE
POSITION OF THE WARM FRONT BEING A FAVORABLE AREA FOR FOG
DEVELOPMENT OVERNIGHT...HAVE REDUCED CIGS OVERNIGHT TO IFR
CONDITIONS.
AS HEATING RESUMES ON WEDNESDAY AND THE WARM FRONT LIFTS FARTHER
NORTH...THE TAF SITES SHOULD RESIDE IN THE THE WARM SECTOR.
HOWEVER FORECAST SOUNDINGS REVEAL FAVORABLE LAPSE RATES FOR
CONVECTION WITH ATTAINABLE CONVECTIVE TEMPS. THUS HAVE MENTIONED
VCTS FOR NOW UNTIL MORE PRECISE TIMING IS POSSIBLE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50/NIELD
SHORT TERM...50
LONG TERM...JH
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
102 PM EDT MON APR 6 2015
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 333 AM EDT MON APR 6 2015
A FRONTAL BOUNDARY WILL SET UP OVER THE OHIO VALLEY AND LOWER GREAT
LAKES THIS WEEK...SERVING AS A FOCAL POINT FOR PERIODS OF SHOWERS
AND THUNDERSTORMS AS WAVES RIPPLE ALONG THE BOUNDARY AND THROUGH THE
REGION. TEMPERATURES WILL BE WARM FOR MUCH OF THIS WEEK. A BRIEF
PERIOD OF DRY WEATHER IS EXPECTED WITH HIGH PRESSURE FOR SATURDAY
BEFORE ANOTHER SYSTEM BRINGS A RETURN TO MORE UNSETTLED WEATHER FOR
THE END OF THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 939 AM EDT MON APR 6 2015
FORECAST IS ON TRACK. SCATTERED LIGHT SHOWERS CONTINUE ACROSS THE
AREA...WITH MOST OF THEM ACROSS THE FAR SOUTH. HRRR INDICATES A FEW
MORE SHOWERS THIS AFTERNOON...ESPECIALLY SOUTHEAST. CURRENT FORECAST
REFLECTS THESE WELL SO ONLY MADE MINOR TWEAKS TO POPS. REMAINDER OF
FORECAST LOOKS GOOD AS WELL.
PREVIOUS DISCUSSION FOLLOWS...
INITIAL SURGE OF MOISTURE OVERSPREADING THE REGION FROM THE
SOUTHWEST EARLY THIS MORNING. AREA OF LIGHT SHOWERS GRADUALLY BEING
GOBBLED UP BY THE AMBIENT DRY AIRMASS PRESENT OVER THE REGION AS
THEY MOVE NORTHEAST. TEMPS WERE GENERALLY IN THE 40S TO LOWER 50S AS
OF 07Z...ALTHOUGH A FEW SPOTS OVER NORTHEAST PORTIONS OF THE
FORECAST AREA HAD SLIPPED INTO THE UPPER 30S.
MID LEVEL CLOUD DECK QUICKLY EXPANDING ACROSS THE FORECAST AREA AND
WILL ENCOMPASS THE ENTIRE REGION PRIOR TO DAYBREAK. AS MENTIONED...
INITIAL BATCH OF LIGHT SHOWERS ARE DIMINISHING AS THEY MOVE
NORTHEAST INTO THE DRY AIRMASS WITH DEWPOINTS IN THE 20S. STILL
THOUGH THIS INITIAL BATCH OF MOISTURE SHOULD BEGIN THE LOW LEVEL
MOISTENING PROCESS OVER CENTRAL INDIANA OVER THE NEXT FEW HOURS.
MOST WIDESPREAD PRECIP ASSOCIATED WITH AN UPPER WAVE WILL PASS TO
THE SOUTH OF THE FORECAST AREA TODAY. INCREASING ISENTROPIC LIFT AND
DEEPENING LOW LEVEL MOISTURE HOWEVER WILL WARRANT A CONTINUED LOW
CHANCE POPS WITH HI-RES WRF/HRRR GUIDANCE SUGGESTING ISOLATED TO
SCATTERED LIGHT SHOWERS WILL BE POSSIBLE THROUGHOUT THE DAY. WITH
THAT BEING SAID...IT WILL NOT BE A WASHOUT BY ANY MEANS WITH
EXTENDED PERIODS OF DRY WEATHER. WEAK ELEVATED INSTABILITY WILL
EXPAND NORTH INTO THE REGION THIS AFTERNOON WITH A MORE SUBSTANTIAL
PUSH OF WARM ADVECTION AND WILL MAINTAIN AN ISOLATED THUNDER MENTION
DURING THE AFTERNOON OVER THE SOUTHERN 2/3 OF THE FORECAST AREA.
TEMPS...THICK STRATUS DEVELOPING DURING THE COURSE OF THE DAY AND
SCATTERED PRECIP WILL SERVE TO KEEP TEMPS DOWN A BIT DESPITE
INCREASING WARM ADVECTION. REALLY HARD TO ARGUE WITH MOS GUIDANCE
WHICH SUPPORTS HIGHS RANGING FROM THE UPPER 50S TO MID 60S.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 333 AM EDT MON APR 6 2015
FORECAST CHALLENGES FOCUS ON CONVECTIVE CHANCES THROUGHOUT THE SHORT
TERM ALONG WITH TEMPS WEDNESDAY AND WEDNESDAY NIGHT WITH
UNCERTAINTIES ON PLACEMENT OF THE FRONTAL BOUNDARY OVER THE REGION.
ACTIVE PATTERN SETTING UP THROUGH MIDWEEK WITH CLASSIC SIGNS FOR A
WET UNSETTLED SPRING REGIME FOR THE OHIO VALLEY. BROAD UPPER TROUGH
MOVING INTO THE WESTERN U S WITH RIDGE AXIS CENTERED OVER THE GULF
OF MEXICO WILL PRODUCE A BROAD SOUTHWEST FLOW THAT WILL ADVECT
PACIFIC MOISTURE INTO THE MISSISSIPPI/OHIO VALLEYS. AT THE
SURFACE...SETUP IS IDEAL FOR A PROLONGED RICH GULF MOISTURE FETCH
INTO THE REGION WITH HIGH PRESSURE OFF THE EAST COAST AND PERSISTENT
LOW PRESSURE OVER THE CENTRAL PLAINS AS PIECES OF ENERGY ALOFT KICK
OUT OF THE WESTERN TROUGH. SEVERAL WAVES WILL TRAVERSE THE FRONTAL
BOUNDARY AS IT OSCILLATES OVER THE REGION FOR THE DURATION OF THE
SHORT TERM.
WHILE POSITION OF THE FRONT AND TIMING OF THE WAVES VARY SLIGHTLY
BETWEEN SPECIFIC MODELS...CONVECTION WILL BE POSSIBLE FOR EVERY
FORECAST PERIOD. FIRST UPPER WAVE SET TO ARRIVE OVER THE REGION
TONIGHT AS A 45KT 850MB JET NOSES INTO THE REGION. AMPLE FORCING
ALOFT AND INCREASING MOISTURE AND INSTABILITY ALL SUPPORT CONVECTIVE
EXPANSION FROM LATE EVENING INTO THE OVERNIGHT. LOCATION OF THE WARM
FRONT OVER NORTH CENTRAL INDIANA SHOULD SERVE AS AN ADDITIONAL
FOCUSING MECHANISM FOR CONVECTION. WILL MAINTAIN LIKELY POPS FOR THE
ENTIRE FORECAST AREA...PRIMARILY FOCUSED AFTER MIDNIGHT. LOCALLY
HEAVY DOWNPOURS WILL BE POSSIBLE THROUGH THE NIGHT AND INTO TUESDAY
MORNING.
MORE WIDESPREAD CONVECTION WILL SHIFT EAST OF THE FORECAST AREA ON
TUESDAY AS SUBTLE RIDGING ALOFT DEVELOPS BEHIND THE UPPER WAVE. WARM
FRONT WILL REMAIN ACROSS NORTHERN COUNTIES WITHIN A MOIST AND
INCREASINGLY UNSTABLE AIRMASS. AMOUNT OF SURFACE HEATING THAT CAN
DEVELOP WILL DETERMINE HOW MUCH CONVECTION CAN GET GOING TUESDAY
AFTERNOON...BUT PRESENCE OF THE INSTABILITY AND WARM FRONT ALONE
SUPPORTS MENTION OF SCATTERED CONVECTION. PLENTIFUL LOW LEVEL
MOISTURE LINGERS WITH SUBSTANTIAL CLEARING LIKELY TO BE DIFFICULT.
LACK OF MORE APPRECIABLE FORCING ALOFT SHOULD LIMIT MORE ROBUST
CONVECTIVE DEVELOPMENT...BUT STRONGER STORMS ARE CERTAINLY A
POSSIBILITY. MODEL SOUNDINGS INDICATING FAIR AMOUNT OF CAPE IN THE
-30 TO -10C LAYER SUPPORT POTENTIAL FOR STRONGER CELLS TO PRODUCE
HAIL.
AS SURFACE WAVE APPROACHES TUESDAY EVENING...CONVECTIVE COVERAGE
SHOULD ONCE AGAIN RAMP UP WITH LIKELY POPS WARRANTED ACROSS MUCH OF
THE FORECAST AREA. ONCE AGAIN...MORE WIDESPREAD PRECIPITATION WILL
DEPART BY EARLY WEDNESDAY AS RIDGING ALOFT RETURNS. SCATTERED
CONVECTION POSSIBLE ON WEDNESDAY AS FRONTAL BOUNDARY SAGS INTO THE
FORECAST AREA. STILL HIGH UNCERTAINTY ON HOW FAR SOUTH THE BOUNDARY
COMES INTO THE FORECAST AREA WEDNESDAY...WITH VASTLY DIFFERENT
WEATHER DEPENDING ON WHICH SIDE OF THE BOUNDARY ONE SITS. NORTH OF
THE FRONT...NORTHEAST WINDS AND MOSTLY CLOUDY SKIES WILL KEEP IT
DAMP AND COOL. SOUTH OF THE FRONT HOWEVER...COULD MAKE A SOLID
ARGUMENT THAT WEDNESDAY WILL BE THE FIRST TRULY WARM HUMID DAY OF
THE SPRING...ESPECIALLY IF THE SUN CAN COME OUT FOR ANY LENGTH OF
TIME. RIGHT NOW...SUSPECT THE BOUNDARY DOES NOT GET ANY FURTHER
SOUTH THAN I-70 BEFORE LIFTING BACK NORTH WEDNESDAY NIGHT IN
RESPONSE TO A STRONGER LOW PRESSURE SYSTEM EJECTING OUT INTO THE
CENTRAL PLAINS. CONVECTIVE COVERAGE WILL ARRIVE OVERNIGHT WEDNESDAY
AS DIFFLUENCE ALOFT DEVELOPS OVER THE REGION AND DEEPER MOISTURE
WITH PRECIP WATER VALUES APPROACHING 1.5 INCHES ADVECT IN.
TEMPS...UNDERCUT HIGHS SLIGHTLY FROM GUIDANCE TUESDAY WITH CLOUD
COVER LINGERING. STILL THINK MUCH OF THE AREA WILL GET INTO THE
LOWER 70S. TEMP FORECAST WEDNESDAY MUCH TRICKIER AND COMPLETELY
DEPENDENT ON THE LOCATION OF THE FRONT. UNDERCUT MOS BY SEVERAL
DEGREES OVER NORTHERN COUNTIES WHERE TEMPS MAY STRUGGLE TO GET MUCH
WARMER THAN THE LOWER 60S. SOUTH OF I-70 HOWEVER...LOW TO MID 70S
LOOK ACHIEVABLE WITH POTENTIAL TO GO EVEN WARMER SHOULD MORE
SUBSTANTIAL CLEARING TAKE PLACE. LEANED TOWARDS MOS FOR OVERNIGHT
LOWS THROUGH THE PERIOD. ONLY EXCEPTION WAS TUESDAY/WEDNESDAY NIGHTS
OVER NORTHERN COUNTIES WHERE WENT COOLER THAN MAVMOS DUE TO FRONTAL
BOUNDARY LOCATION.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 333 AM EDT MON APR 6 2015
ENSEMBLES INDICATE AN ACTIVE AND PROGRESSIVE FLOW ACROSS THE AREA
DURING THIS PERIOD. A MEAN UPPER TROUGH IS EXPECTED TO PASS OVER THE
GREAT LAKES LATE THIS WEEK...WITH THE POTENTIAL FOR ANOTHER LONG
WAVE TROUGH TO MOVE INTO THE PLAINS BY NEXT SUNDAY.
WILL KEEP POPS IN THE FORECAST FOR THURSDAY AND FRIDAY AS SURFACE
SYSTEM ASSOCIATED WITH THE FIRST TROUGH PASSES THROUGH THE AREA.
PROGGED PRECIPITABLE WATERS OFF THE OPERATIONAL MODELS ARE WELL
ABOVE NORMAL ON THURSDAY...SO HEAVY RAINS ARE POSSIBLE. THIS SYSTEM
MAY BE QUITE DYNAMIC AS WELL...WITH SOME OF THE OPERATIONAL MODEL
GUIDANCE SUGGESTING AN ASSOCIATED MID LEVEL JET AROUND 80 KTS.
APPEARS THE SURFACE FRONT WILL GET ENOUGH OF A SHOVE EAST TO END THE
PRECIPITATION THREAT BY SATURDAY.
ENSEMBLES SUGGEST THE PRECIPITATION THREAT MAY MOVE BACK INTO THE
AREA AS EARLY AS NEXT SUNDAY IN THE WARM ADVECTION PATTERN THAT
DEVELOPS AHEAD OF NEXT PLAINS TROUGH. WILL GO WITH CHANCE POPS FOR
NEXT SUNDAY.
&&
.AVIATION /DISCUSSION FOR THE 061800Z TAF ISSUANCE/...
ISSUED AT 102 PM EDT MON APR 6 2015
FLIGHT CONDITIONS LOWERING TO MVFR THIS AFTERNOON AND TO IFR OR LIFR
BY LATE EVENING ON...WITH SOME IMPROVEMENT BY MIDDAY TUESDAY.
A WARM/MOIST SOUTHERLY FLOW WILL RESULT IN CEILINGS GRADUALLY
FALLING THIS AFTERNOON AND TONIGHT. ISOLATED SHOWERS ARE POSSIBLE
THIS AFTERNOON AND EARLY TONIGHT. HIGH RESOLUTION MODELS INDICATE
SHOWERS WILL BECOME MORE NUMEROUS BY MIDNIGHT AS A LOW LEVEL JET
STRENGTHENS TO OUR SOUTH. MODELS INDICATE SOME ELEVATED INSTABILITY
LATER TONIGHT AND WILL ADD VCTS TO TAF SITES AS WIDELY SCATTERED
THUNDERSTORMS ALSO POSSIBLE.
ON TUESDAY EXPECT NUMEROUS SHOWERS AND A FEW THUNDERSTORMS TUESDAY
MORNING. MODELS HINT AT A POSSIBLE LULL IN CONVECTION TUESDAY
AFTERNOON AND CEILINGS MAY IMPROVE TO MVFR BY MIDDAY ON.
SOUTH OR SOUTHWEST WINDS OF 10 TO 12 KNOTS WILL BECOME SOUTH 8 KNOTS
OR LESS TONIGHT AND SOUTHWEST UP TO 12 KNOTS BY MIDDAY
TUESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN/50
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1026 AM EDT MON APR 6 2015
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 333 AM EDT MON APR 6 2015
A FRONTAL BOUNDARY WILL SET UP OVER THE OHIO VALLEY AND LOWER GREAT
LAKES THIS WEEK...SERVING AS A FOCAL POINT FOR PERIODS OF SHOWERS
AND THUNDERSTORMS AS WAVES RIPPLE ALONG THE BOUNDARY AND THROUGH THE
REGION. TEMPERATURES WILL BE WARM FOR MUCH OF THIS WEEK. A BRIEF
PERIOD OF DRY WEATHER IS EXPECTED WITH HIGH PRESSURE FOR SATURDAY
BEFORE ANOTHER SYSTEM BRINGS A RETURN TO MORE UNSETTLED WEATHER FOR
THE END OF THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 939 AM EDT MON APR 6 2015
FORECAST IS ON TRACK. SCATTERED LIGHT SHOWERS CONTINUE ACROSS THE
AREA...WITH MOST OF THEM ACROSS THE FAR SOUTH. HRRR INDICATES A FEW
MORE SHOWERS THIS AFTERNOON...ESPECIALLY SOUTHEAST. CURRENT FORECAST
REFLECTS THESE WELL SO ONLY MADE MINOR TWEAKS TO POPS. REMAINDER OF
FORECAST LOOKS GOOD AS WELL.
PREVIOUS DISCUSSION FOLLOWS...
INITIAL SURGE OF MOISTURE OVERSPREADING THE REGION FROM THE
SOUTHWEST EARLY THIS MORNING. AREA OF LIGHT SHOWERS GRADUALLY BEING
GOBBLED UP BY THE AMBIENT DRY AIRMASS PRESENT OVER THE REGION AS
THEY MOVE NORTHEAST. TEMPS WERE GENERALLY IN THE 40S TO LOWER 50S AS
OF 07Z...ALTHOUGH A FEW SPOTS OVER NORTHEAST PORTIONS OF THE
FORECAST AREA HAD SLIPPED INTO THE UPPER 30S.
MID LEVEL CLOUD DECK QUICKLY EXPANDING ACROSS THE FORECAST AREA AND
WILL ENCOMPASS THE ENTIRE REGION PRIOR TO DAYBREAK. AS MENTIONED...
INITIAL BATCH OF LIGHT SHOWERS ARE DIMINISHING AS THEY MOVE
NORTHEAST INTO THE DRY AIRMASS WITH DEWPOINTS IN THE 20S. STILL
THOUGH THIS INITIAL BATCH OF MOISTURE SHOULD BEGIN THE LOW LEVEL
MOISTENING PROCESS OVER CENTRAL INDIANA OVER THE NEXT FEW HOURS.
MOST WIDESPREAD PRECIP ASSOCIATED WITH AN UPPER WAVE WILL PASS TO
THE SOUTH OF THE FORECAST AREA TODAY. INCREASING ISENTROPIC LIFT AND
DEEPENING LOW LEVEL MOISTURE HOWEVER WILL WARRANT A CONTINUED LOW
CHANCE POPS WITH HI-RES WRF/HRRR GUIDANCE SUGGESTING ISOLATED TO
SCATTERED LIGHT SHOWERS WILL BE POSSIBLE THROUGHOUT THE DAY. WITH
THAT BEING SAID...IT WILL NOT BE A WASHOUT BY ANY MEANS WITH
EXTENDED PERIODS OF DRY WEATHER. WEAK ELEVATED INSTABILITY WILL
EXPAND NORTH INTO THE REGION THIS AFTERNOON WITH A MORE SUBSTANTIAL
PUSH OF WARM ADVECTION AND WILL MAINTAIN AN ISOLATED THUNDER MENTION
DURING THE AFTERNOON OVER THE SOUTHERN 2/3 OF THE FORECAST AREA.
TEMPS...THICK STRATUS DEVELOPING DURING THE COURSE OF THE DAY AND
SCATTERED PRECIP WILL SERVE TO KEEP TEMPS DOWN A BIT DESPITE
INCREASING WARM ADVECTION. REALLY HARD TO ARGUE WITH MOS GUIDANCE
WHICH SUPPORTS HIGHS RANGING FROM THE UPPER 50S TO MID 60S.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 333 AM EDT MON APR 6 2015
FORECAST CHALLENGES FOCUS ON CONVECTIVE CHANCES THROUGHOUT THE SHORT
TERM ALONG WITH TEMPS WEDNESDAY AND WEDNESDAY NIGHT WITH
UNCERTAINTIES ON PLACEMENT OF THE FRONTAL BOUNDARY OVER THE REGION.
ACTIVE PATTERN SETTING UP THROUGH MIDWEEK WITH CLASSIC SIGNS FOR A
WET UNSETTLED SPRING REGIME FOR THE OHIO VALLEY. BROAD UPPER TROUGH
MOVING INTO THE WESTERN U S WITH RIDGE AXIS CENTERED OVER THE GULF
OF MEXICO WILL PRODUCE A BROAD SOUTHWEST FLOW THAT WILL ADVECT
PACIFIC MOISTURE INTO THE MISSISSIPPI/OHIO VALLEYS. AT THE
SURFACE...SETUP IS IDEAL FOR A PROLONGED RICH GULF MOISTURE FETCH
INTO THE REGION WITH HIGH PRESSURE OFF THE EAST COAST AND PERSISTENT
LOW PRESSURE OVER THE CENTRAL PLAINS AS PIECES OF ENERGY ALOFT KICK
OUT OF THE WESTERN TROUGH. SEVERAL WAVES WILL TRAVERSE THE FRONTAL
BOUNDARY AS IT OSCILLATES OVER THE REGION FOR THE DURATION OF THE
SHORT TERM.
WHILE POSITION OF THE FRONT AND TIMING OF THE WAVES VARY SLIGHTLY
BETWEEN SPECIFIC MODELS...CONVECTION WILL BE POSSIBLE FOR EVERY
FORECAST PERIOD. FIRST UPPER WAVE SET TO ARRIVE OVER THE REGION
TONIGHT AS A 45KT 850MB JET NOSES INTO THE REGION. AMPLE FORCING
ALOFT AND INCREASING MOISTURE AND INSTABILITY ALL SUPPORT CONVECTIVE
EXPANSION FROM LATE EVENING INTO THE OVERNIGHT. LOCATION OF THE WARM
FRONT OVER NORTH CENTRAL INDIANA SHOULD SERVE AS AN ADDITIONAL
FOCUSING MECHANISM FOR CONVECTION. WILL MAINTAIN LIKELY POPS FOR THE
ENTIRE FORECAST AREA...PRIMARILY FOCUSED AFTER MIDNIGHT. LOCALLY
HEAVY DOWNPOURS WILL BE POSSIBLE THROUGH THE NIGHT AND INTO TUESDAY
MORNING.
MORE WIDESPREAD CONVECTION WILL SHIFT EAST OF THE FORECAST AREA ON
TUESDAY AS SUBTLE RIDGING ALOFT DEVELOPS BEHIND THE UPPER WAVE. WARM
FRONT WILL REMAIN ACROSS NORTHERN COUNTIES WITHIN A MOIST AND
INCREASINGLY UNSTABLE AIRMASS. AMOUNT OF SURFACE HEATING THAT CAN
DEVELOP WILL DETERMINE HOW MUCH CONVECTION CAN GET GOING TUESDAY
AFTERNOON...BUT PRESENCE OF THE INSTABILITY AND WARM FRONT ALONE
SUPPORTS MENTION OF SCATTERED CONVECTION. PLENTIFUL LOW LEVEL
MOISTURE LINGERS WITH SUBSTANTIAL CLEARING LIKELY TO BE DIFFICULT.
LACK OF MORE APPRECIABLE FORCING ALOFT SHOULD LIMIT MORE ROBUST
CONVECTIVE DEVELOPMENT...BUT STRONGER STORMS ARE CERTAINLY A
POSSIBILITY. MODEL SOUNDINGS INDICATING FAIR AMOUNT OF CAPE IN THE
-30 TO -10C LAYER SUPPORT POTENTIAL FOR STRONGER CELLS TO PRODUCE
HAIL.
AS SURFACE WAVE APPROACHES TUESDAY EVENING...CONVECTIVE COVERAGE
SHOULD ONCE AGAIN RAMP UP WITH LIKELY POPS WARRANTED ACROSS MUCH OF
THE FORECAST AREA. ONCE AGAIN...MORE WIDESPREAD PRECIPITATION WILL
DEPART BY EARLY WEDNESDAY AS RIDGING ALOFT RETURNS. SCATTERED
CONVECTION POSSIBLE ON WEDNESDAY AS FRONTAL BOUNDARY SAGS INTO THE
FORECAST AREA. STILL HIGH UNCERTAINTY ON HOW FAR SOUTH THE BOUNDARY
COMES INTO THE FORECAST AREA WEDNESDAY...WITH VASTLY DIFFERENT
WEATHER DEPENDING ON WHICH SIDE OF THE BOUNDARY ONE SITS. NORTH OF
THE FRONT...NORTHEAST WINDS AND MOSTLY CLOUDY SKIES WILL KEEP IT
DAMP AND COOL. SOUTH OF THE FRONT HOWEVER...COULD MAKE A SOLID
ARGUMENT THAT WEDNESDAY WILL BE THE FIRST TRULY WARM HUMID DAY OF
THE SPRING...ESPECIALLY IF THE SUN CAN COME OUT FOR ANY LENGTH OF
TIME. RIGHT NOW...SUSPECT THE BOUNDARY DOES NOT GET ANY FURTHER
SOUTH THAN I-70 BEFORE LIFTING BACK NORTH WEDNESDAY NIGHT IN
RESPONSE TO A STRONGER LOW PRESSURE SYSTEM EJECTING OUT INTO THE
CENTRAL PLAINS. CONVECTIVE COVERAGE WILL ARRIVE OVERNIGHT WEDNESDAY
AS DIFFLUENCE ALOFT DEVELOPS OVER THE REGION AND DEEPER MOISTURE
WITH PRECIP WATER VALUES APPROACHING 1.5 INCHES ADVECT IN.
TEMPS...UNDERCUT HIGHS SLIGHTLY FROM GUIDANCE TUESDAY WITH CLOUD
COVER LINGERING. STILL THINK MUCH OF THE AREA WILL GET INTO THE
LOWER 70S. TEMP FORECAST WEDNESDAY MUCH TRICKIER AND COMPLETELY
DEPENDENT ON THE LOCATION OF THE FRONT. UNDERCUT MOS BY SEVERAL
DEGREES OVER NORTHERN COUNTIES WHERE TEMPS MAY STRUGGLE TO GET MUCH
WARMER THAN THE LOWER 60S. SOUTH OF I-70 HOWEVER...LOW TO MID 70S
LOOK ACHIEVABLE WITH POTENTIAL TO GO EVEN WARMER SHOULD MORE
SUBSTANTIAL CLEARING TAKE PLACE. LEANED TOWARDS MOS FOR OVERNIGHT
LOWS THROUGH THE PERIOD. ONLY EXCEPTION WAS TUESDAY/WEDNESDAY NIGHTS
OVER NORTHERN COUNTIES WHERE WENT COOLER THAN MAVMOS DUE TO FRONTAL
BOUNDARY LOCATION.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 333 AM EDT MON APR 6 2015
ENSEMBLES INDICATE AN ACTIVE AND PROGRESSIVE FLOW ACROSS THE AREA
DURING THIS PERIOD. A MEAN UPPER TROUGH IS EXPECTED TO PASS OVER THE
GREAT LAKES LATE THIS WEEK...WITH THE POTENTIAL FOR ANOTHER LONG
WAVE TROUGH TO MOVE INTO THE PLAINS BY NEXT SUNDAY.
WILL KEEP POPS IN THE FORECAST FOR THURSDAY AND FRIDAY AS SURFACE
SYSTEM ASSOCIATED WITH THE FIRST TROUGH PASSES THROUGH THE AREA.
PROGGED PRECIPITABLE WATERS OFF THE OPERATIONAL MODELS ARE WELL
ABOVE NORMAL ON THURSDAY...SO HEAVY RAINS ARE POSSIBLE. THIS SYSTEM
MAY BE QUITE DYNAMIC AS WELL...WITH SOME OF THE OPERATIONAL MODEL
GUIDANCE SUGGESTING AN ASSOCIATED MID LEVEL JET AROUND 80 KTS.
APPEARS THE SURFACE FRONT WILL GET ENOUGH OF A SHOVE EAST TO END THE
PRECIPITATION THREAT BY SATURDAY.
ENSEMBLES SUGGEST THE PRECIPITATION THREAT MAY MOVE BACK INTO THE
AREA AS EARLY AS NEXT SUNDAY IN THE WARM ADVECTION PATTERN THAT
DEVELOPS AHEAD OF NEXT PLAINS TROUGH. WILL GO WITH CHANCE POPS FOR
NEXT SUNDAY.
&&
.AVIATION /DISCUSSION FOR THE 061500Z KIND TAF UPDATE/...
ISSUED AT 1026 AM EDT MON APR 6 2015
MINOR TWEAKS MADE TO KIND TAF TO BETTER MATCH CURRENT CONDITIONS.
NO OTHER CHANGES ARE NEEDED AT THIS TIME.
PREVIOUS AVIATION DISCUSSION FOLLOWS...
SUSTAINED WARM/MOIST ADVECTION TODAY WILL RESULT IN CEILINGS
GRADUALLY FALLING DURING THE DAY...REACHING THE MVFR CATEGORY LATER
THIS MORNING OR DURING THE EARLY AFTERNOON HOURS. APPEARS CEILINGS
WILL LIKELY REMAIN ABOVE IFR UNTIL TOWARDS/AFTER 070000Z.
A PERIOD OF LIGHT SHOWERS IS POSSIBLE AT THE TAF SITES THROUGH THE
LATE MORNING HOURS...AND MAYBE ANOTHER ENHANCED CHANCE LATER THIS
AFTERNOON. LIFT LOOKS RATHER DISORGANIZED TODAY...SO EXPECTING ANY
SHOWER ACTIVITY TO BE SCATTERED IN NATURE WITH LITTLE IMPACT ON
VISIBILITIES FOR ANY PROLONGED PERIODS OF TIME.
MODELS SUGGEST A DECENT AMOUNT OF ELEVATED INSTABILITY WILL BE
MOVING INTO THE AREA THIS EVENING...SO CONVECTIVE THREAT EXPECTED TO
INCREASE ACROSS THE TAF SITES AFTER DARK.
SURFACE WINDS GENERALLY 170-190 DEGREES AT 7-10 KTS TODAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN/50
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS/JH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
939 AM EDT MON APR 6 2015
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 333 AM EDT MON APR 6 2015
A FRONTAL BOUNDARY WILL SET UP OVER THE OHIO VALLEY AND LOWER GREAT
LAKES THIS WEEK...SERVING AS A FOCAL POINT FOR PERIODS OF SHOWERS
AND THUNDERSTORMS AS WAVES RIPPLE ALONG THE BOUNDARY AND THROUGH THE
REGION. TEMPERATURES WILL BE WARM FOR MUCH OF THIS WEEK. A BRIEF
PERIOD OF DRY WEATHER IS EXPECTED WITH HIGH PRESSURE FOR SATURDAY
BEFORE ANOTHER SYSTEM BRINGS A RETURN TO MORE UNSETTLED WEATHER FOR
THE END OF THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 939 AM EDT MON APR 6 2015
FORECAST IS ON TRACK. SCATTERED LIGHT SHOWERS CONTINUE ACROSS THE
AREA...WITH MOST OF THEM ACROSS THE FAR SOUTH. HRRR INDICATES A FEW
MORE SHOWERS THIS AFTERNOON...ESPECIALLY SOUTHEAST. CURRENT FORECAST
REFLECTS THESE WELL SO ONLY MADE MINOR TWEAKS TO POPS. REMAINDER OF
FORECAST LOOKS GOOD AS WELL.
PREVIOUS DISCUSSION FOLLOWS...
INITIAL SURGE OF MOISTURE OVERSPREADING THE REGION FROM THE
SOUTHWEST EARLY THIS MORNING. AREA OF LIGHT SHOWERS GRADUALLY BEING
GOBBLED UP BY THE AMBIENT DRY AIRMASS PRESENT OVER THE REGION AS
THEY MOVE NORTHEAST. TEMPS WERE GENERALLY IN THE 40S TO LOWER 50S AS
OF 07Z...ALTHOUGH A FEW SPOTS OVER NORTHEAST PORTIONS OF THE
FORECAST AREA HAD SLIPPED INTO THE UPPER 30S.
MID LEVEL CLOUD DECK QUICKLY EXPANDING ACROSS THE FORECAST AREA AND
WILL ENCOMPASS THE ENTIRE REGION PRIOR TO DAYBREAK. AS MENTIONED...
INITIAL BATCH OF LIGHT SHOWERS ARE DIMINISHING AS THEY MOVE
NORTHEAST INTO THE DRY AIRMASS WITH DEWPOINTS IN THE 20S. STILL
THOUGH THIS INITIAL BATCH OF MOISTURE SHOULD BEGIN THE LOW LEVEL
MOISTENING PROCESS OVER CENTRAL INDIANA OVER THE NEXT FEW HOURS.
MOST WIDESPREAD PRECIP ASSOCIATED WITH AN UPPER WAVE WILL PASS TO
THE SOUTH OF THE FORECAST AREA TODAY. INCREASING ISENTROPIC LIFT AND
DEEPENING LOW LEVEL MOISTURE HOWEVER WILL WARRANT A CONTINUED LOW
CHANCE POPS WITH HI-RES WRF/HRRR GUIDANCE SUGGESTING ISOLATED TO
SCATTERED LIGHT SHOWERS WILL BE POSSIBLE THROUGHOUT THE DAY. WITH
THAT BEING SAID...IT WILL NOT BE A WASHOUT BY ANY MEANS WITH
EXTENDED PERIODS OF DRY WEATHER. WEAK ELEVATED INSTABILITY WILL
EXPAND NORTH INTO THE REGION THIS AFTERNOON WITH A MORE SUBSTANTIAL
PUSH OF WARM ADVECTION AND WILL MAINTAIN AN ISOLATED THUNDER MENTION
DURING THE AFTERNOON OVER THE SOUTHERN 2/3 OF THE FORECAST AREA.
TEMPS...THICK STRATUS DEVELOPING DURING THE COURSE OF THE DAY AND
SCATTERED PRECIP WILL SERVE TO KEEP TEMPS DOWN A BIT DESPITE
INCREASING WARM ADVECTION. REALLY HARD TO ARGUE WITH MOS GUIDANCE
WHICH SUPPORTS HIGHS RANGING FROM THE UPPER 50S TO MID 60S.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
ISSUED AT 333 AM EDT MON APR 6 2015
FORECAST CHALLENGES FOCUS ON CONVECTIVE CHANCES THROUGHOUT THE SHORT
TERM ALONG WITH TEMPS WEDNESDAY AND WEDNESDAY NIGHT WITH
UNCERTAINTIES ON PLACEMENT OF THE FRONTAL BOUNDARY OVER THE REGION.
ACTIVE PATTERN SETTING UP THROUGH MIDWEEK WITH CLASSIC SIGNS FOR A
WET UNSETTLED SPRING REGIME FOR THE OHIO VALLEY. BROAD UPPER TROUGH
MOVING INTO THE WESTERN U S WITH RIDGE AXIS CENTERED OVER THE GULF
OF MEXICO WILL PRODUCE A BROAD SOUTHWEST FLOW THAT WILL ADVECT
PACIFIC MOISTURE INTO THE MISSISSIPPI/OHIO VALLEYS. AT THE
SURFACE...SETUP IS IDEAL FOR A PROLONGED RICH GULF MOISTURE FETCH
INTO THE REGION WITH HIGH PRESSURE OFF THE EAST COAST AND PERSISTENT
LOW PRESSURE OVER THE CENTRAL PLAINS AS PIECES OF ENERGY ALOFT KICK
OUT OF THE WESTERN TROUGH. SEVERAL WAVES WILL TRAVERSE THE FRONTAL
BOUNDARY AS IT OSCILLATES OVER THE REGION FOR THE DURATION OF THE
SHORT TERM.
WHILE POSITION OF THE FRONT AND TIMING OF THE WAVES VARY SLIGHTLY
BETWEEN SPECIFIC MODELS...CONVECTION WILL BE POSSIBLE FOR EVERY
FORECAST PERIOD. FIRST UPPER WAVE SET TO ARRIVE OVER THE REGION
TONIGHT AS A 45KT 850MB JET NOSES INTO THE REGION. AMPLE FORCING
ALOFT AND INCREASING MOISTURE AND INSTABILITY ALL SUPPORT CONVECTIVE
EXPANSION FROM LATE EVENING INTO THE OVERNIGHT. LOCATION OF THE WARM
FRONT OVER NORTH CENTRAL INDIANA SHOULD SERVE AS AN ADDITIONAL
FOCUSING MECHANISM FOR CONVECTION. WILL MAINTAIN LIKELY POPS FOR THE
ENTIRE FORECAST AREA...PRIMARILY FOCUSED AFTER MIDNIGHT. LOCALLY
HEAVY DOWNPOURS WILL BE POSSIBLE THROUGH THE NIGHT AND INTO TUESDAY
MORNING.
MORE WIDESPREAD CONVECTION WILL SHIFT EAST OF THE FORECAST AREA ON
TUESDAY AS SUBTLE RIDGING ALOFT DEVELOPS BEHIND THE UPPER WAVE. WARM
FRONT WILL REMAIN ACROSS NORTHERN COUNTIES WITHIN A MOIST AND
INCREASINGLY UNSTABLE AIRMASS. AMOUNT OF SURFACE HEATING THAT CAN
DEVELOP WILL DETERMINE HOW MUCH CONVECTION CAN GET GOING TUESDAY
AFTERNOON...BUT PRESENCE OF THE INSTABILITY AND WARM FRONT ALONE
SUPPORTS MENTION OF SCATTERED CONVECTION. PLENTIFUL LOW LEVEL
MOISTURE LINGERS WITH SUBSTANTIAL CLEARING LIKELY TO BE DIFFICULT.
LACK OF MORE APPRECIABLE FORCING ALOFT SHOULD LIMIT MORE ROBUST
CONVECTIVE DEVELOPMENT...BUT STRONGER STORMS ARE CERTAINLY A
POSSIBILITY. MODEL SOUNDINGS INDICATING FAIR AMOUNT OF CAPE IN THE
-30 TO -10C LAYER SUPPORT POTENTIAL FOR STRONGER CELLS TO PRODUCE
HAIL.
AS SURFACE WAVE APPROACHES TUESDAY EVENING...CONVECTIVE COVERAGE
SHOULD ONCE AGAIN RAMP UP WITH LIKELY POPS WARRANTED ACROSS MUCH OF
THE FORECAST AREA. ONCE AGAIN...MORE WIDESPREAD PRECIPITATION WILL
DEPART BY EARLY WEDNESDAY AS RIDGING ALOFT RETURNS. SCATTERED
CONVECTION POSSIBLE ON WEDNESDAY AS FRONTAL BOUNDARY SAGS INTO THE
FORECAST AREA. STILL HIGH UNCERTAINTY ON HOW FAR SOUTH THE BOUNDARY
COMES INTO THE FORECAST AREA WEDNESDAY...WITH VASTLY DIFFERENT
WEATHER DEPENDING ON WHICH SIDE OF THE BOUNDARY ONE SITS. NORTH OF
THE FRONT...NORTHEAST WINDS AND MOSTLY CLOUDY SKIES WILL KEEP IT
DAMP AND COOL. SOUTH OF THE FRONT HOWEVER...COULD MAKE A SOLID
ARGUMENT THAT WEDNESDAY WILL BE THE FIRST TRULY WARM HUMID DAY OF
THE SPRING...ESPECIALLY IF THE SUN CAN COME OUT FOR ANY LENGTH OF
TIME. RIGHT NOW...SUSPECT THE BOUNDARY DOES NOT GET ANY FURTHER
SOUTH THAN I-70 BEFORE LIFTING BACK NORTH WEDNESDAY NIGHT IN
RESPONSE TO A STRONGER LOW PRESSURE SYSTEM EJECTING OUT INTO THE
CENTRAL PLAINS. CONVECTIVE COVERAGE WILL ARRIVE OVERNIGHT WEDNESDAY
AS DIFFLUENCE ALOFT DEVELOPS OVER THE REGION AND DEEPER MOISTURE
WITH PRECIP WATER VALUES APPROACHING 1.5 INCHES ADVECT IN.
TEMPS...UNDERCUT HIGHS SLIGHTLY FROM GUIDANCE TUESDAY WITH CLOUD
COVER LINGERING. STILL THINK MUCH OF THE AREA WILL GET INTO THE
LOWER 70S. TEMP FORECAST WEDNESDAY MUCH TRICKIER AND COMPLETELY
DEPENDENT ON THE LOCATION OF THE FRONT. UNDERCUT MOS BY SEVERAL
DEGREES OVER NORTHERN COUNTIES WHERE TEMPS MAY STRUGGLE TO GET MUCH
WARMER THAN THE LOWER 60S. SOUTH OF I-70 HOWEVER...LOW TO MID 70S
LOOK ACHIEVABLE WITH POTENTIAL TO GO EVEN WARMER SHOULD MORE
SUBSTANTIAL CLEARING TAKE PLACE. LEANED TOWARDS MOS FOR OVERNIGHT
LOWS THROUGH THE PERIOD. ONLY EXCEPTION WAS TUESDAY/WEDNESDAY NIGHTS
OVER NORTHERN COUNTIES WHERE WENT COOLER THAN MAVMOS DUE TO FRONTAL
BOUNDARY LOCATION.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
ISSUED AT 333 AM EDT MON APR 6 2015
ENSEMBLES INDICATE AN ACTIVE AND PROGRESSIVE FLOW ACROSS THE AREA
DURING THIS PERIOD. A MEAN UPPER TROUGH IS EXPECTED TO PASS OVER THE
GREAT LAKES LATE THIS WEEK...WITH THE POTENTIAL FOR ANOTHER LONG
WAVE TROUGH TO MOVE INTO THE PLAINS BY NEXT SUNDAY.
WILL KEEP POPS IN THE FORECAST FOR THURSDAY AND FRIDAY AS SURFACE
SYSTEM ASSOCIATED WITH THE FIRST TROUGH PASSES THROUGH THE AREA.
PROGGED PRECIPITABLE WATERS OFF THE OPERATIONAL MODELS ARE WELL
ABOVE NORMAL ON THURSDAY...SO HEAVY RAINS ARE POSSIBLE. THIS SYSTEM
MAY BE QUITE DYNAMIC AS WELL...WITH SOME OF THE OPERATIONAL MODEL
GUIDANCE SUGGESTING AN ASSOCIATED MID LEVEL JET AROUND 80 KTS.
APPEARS THE SURFACE FRONT WILL GET ENOUGH OF A SHOVE EAST TO END THE
PRECIPITATION THREAT BY SATURDAY.
ENSEMBLES SUGGEST THE PRECIPITATION THREAT MAY MOVE BACK INTO THE
AREA AS EARLY AS NEXT SUNDAY IN THE WARM ADVECTION PATTERN THAT
DEVELOPS AHEAD OF NEXT PLAINS TROUGH. WILL GO WITH CHANCE POPS FOR
NEXT SUNDAY.
&&
.AVIATION /DISCUSSION FOR THE 061200Z TAFS/...
ISSUED AT 632 AM EDT MON APR 6 2015
SUSTAINED WARM/MOIST ADVECTION TODAY WILL RESULT IN CEILINGS
GRADUALLY FALLING DURING THE DAY...REACHING THE MVFR CATEGORY LATER
THIS MORNING OR DURING THE EARLY AFTERNOON HOURS. APPEARS CEILINGS
WILL LIKELY REMAIN ABOVE IFR UNTIL TOWARDS/AFTER 070000Z.
A PERIOD OF LIGHT SHOWERS IS POSSIBLE AT THE TAF SITES THROUGH THE
LATE MORNING HOURS...AND MAYBE ANOTHER ENHANCED CHANCE LATER THIS
AFTERNOON. LIFT LOOKS RATHER DISORGANIZED TODAY...SO EXPECTING ANY
SHOWER ACTIVITY TO BE SCATTERED IN NATURE WITH LITTLE IMPACT ON
VISIBILITIES FOR ANY PROLONGED PERIODS OF TIME.
MODELS SUGGEST A DECENT AMOUNT OF ELEVATED INSTABILITY WILL BE
MOVING INTO THE AREA THIS EVENING...SO CONVECTIVE THREAT EXPECTED TO
INCREASE ACROSS THE TAF SITES AFTER DARK.
SURFACE WINDS GENERALLY 170-190 DEGREES AT 7-10 KTS TODAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN/50
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS
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AREA FORECAST DISCUSSION
NWS TOPEKA KS
404 PM CDT Mon Apr 6 2015
.SHORT TERM...(This Evening through Tuesday)
Issued at 359 PM CDT MON APR 6 2015
An amplified upper level trough off the northern CA coast will
slowly dig east-southeast across CA into western NV by late Monday
Afternoon. The southwesterly mid and upper level flow across the
plains will increase through the period with 45 to 50kt 500 mb winds
moving northeast across the state of KS by late Tuesday afternoon.
Tonight, southerly low-level winds will begin to advect deep Gulf
moisture north-northeast across the CWA. The ARW, RUC and NAM models
all show isentropic lift at the 300K level increasing across
northeast KS towards 6Z. The resulting lift may cause elevated
thunderstorms to develop, especially north of I-70 and east of a
Manhattan to Marysville line. The EML over spreading the area Today
will allow for steep lapse rates. The NAM and ARW models show
MUCAPES of 3,000 to 4,000 J/KG and Effective shear of 30 to 40 KTS
above the inversion across portions of east central and northeast KS
from 3Z to 9Z. Therefore some of the elevated thunderstorms may
produce large hail, especially if any of the elevated storms can
rotate at mid-levels. The elevated thunderstorms should move
northeast into IA and northern MO by 12Z.
Tuesday, a surface front will move southward across the CWA through
the day. The northern counties of the CWA may remain cloudy north
of the front. As the front moves southeastward into northeast and
east central KS, the front will encounter deeper gulf moisture and
the surface convergence will increase along the front through the
Afternoon hours. The NAM and ARW show a dryline punch advecting
northeast from south central KS towards EMP. The NAM forecast
soundings show the CAP at EMP nearly removed as temperatures will
warm into the mid 80s ahead the cold front across southern Lyon
county. The NAM model develops QPF across Osage county along the
front between 21 and 24Z TUE, while the ARW shows QPF developing
across Jefferson county ahead of the surface front. Since there is a
chance for the CAP to break along the front late Tuesday Afternoon,
I have inserted an area of isolated thunderstorms along and just
north of the boundary. If surface based storms develop along the
front across east central KS they will most likely become severe.
Most models show between 3,000 and 4,500 J/KG MLCAPE developing in
the warm sector ahead of the front across east central KS. The
effective shear between the surface and 500mb will be around 45
KTS, which given the high MLCAPE would favor supercell
thunderstorms that would produce large hail and damaging wind
gusts. The 850mb winds will veer to the southwest through the day,
thus the low-level vertical wind shear will not be favorable for
tornadoes, unless a storm moves along the boundary and the updraft
does not become undercut, then there may be a chance for a
supercell to produce a tornado. There is s chance that the CAP may
hold Tuesday Afternoon and the front may move through the CWA dry.
Highs will vary from the lower to mid 80s across east central KS
to the mid 60s across north central KS.
.LONG TERM...(Tuesday Night through Monday)
Issued at 359 PM CDT MON APR 6 2015
An active weather pattern is expected for the middle part of this
week with periods of strong to severe thunderstorms likely.
By Tuesday night, a mid-level trough will be digging southward
across the far western U.S. before becoming positively tilted as it
advances towards the Rockies on Wed. At the surface, low pressure
will be centered near the Oklahoma panhandle with an associated cold
front extending into east central Kansas by the late afternoon and
evening hours on Tue. There still are some model discrepancies with
the exact placement of this boundary, but more models have been
trending toward the cap eroding away significantly enough during the
afternoon hours to support the potential for some isolated to widely
scattered thunderstorm development late afternoon through early
evening hours before becoming elevated by mid/late evening. If the
cap is in fact able to weaken, then models suggest significant
instability with surface-based CAPE of values upwards of around
2500-3500J/kg and 0-6km bulk shear of 35-45kts. Any storms that
develop will likely be supercells and the primary threats will be
large hail and damaging winds. Have added a mention of slight chance
PoPs for scattered thunderstorms for the entire CWA overnight into
Wed. morning as models show increasing isentropic lift. As a result,
could see scattered elevated storms into Wed. morning.
The best chance for severe storms will be on Wed. as the front
gradually lifts northward across the area as a warm front. There are
still some model discrepancies with regards to how far north the
warm front will track across the area, which will have a significant
impact on temperatures. It looks to be a strong enough boundary that
a decent temperature gradient should set up somewhere north of I-70,
with highs ranging from the middle 60s to near 80 degrees from
northwest to southeast. With much of the southeastern half of the
forecast area expected to be in the warm sector through the day,
breezy southerly winds will support warm-air advection into east
central Kansas and also lead to decent moisture advection as
dewpoints look to rise into the 60s. The dryline looks to extend
into central/south central Kansas Wed. afternoon and south central
Kansas may be the initiation point for isolated to scattered
supercell thunderstorm development as the triple-point should be
located near or just north of the Wichita area. With the warm front
only pivoting slightly over the area into Wednesday evening and with
an increasing southwesterly low-level jet nearly parallel to the
boundary, expect storms to track northeastward along the boundary.
The cap looks to significantly weaken during the afternoon hours and
conditions will be prime for strong to severe supercell thunderstorm
development as CAPE values reach 3000-3500J/kg, 40-50kts of 0-6km shear,
and 150-250m2/s2 of 0-1km helicity. With these healthy conditions in
place, expect isolated to scattered supercells with large hail,
damaging winds, and some tornadoes possible. This will be a day that
we want to continue to keep a very close eye on.
Expect thunderstorms to continue through the overnight hours into
Thursday morning, but soundings show that this activity should
become elevated. By Thursday morning, models show the mid-level
trough moving into the Central Plains and will pivot from being
positively-tilted to negatively-tilted. This pivot in the tilt will
allow the trough to more quickly push the low pressure system and
associated cold front eastward out of the area and, thus, have
continued to trend with a faster exit of precipitation out of the
area with dry conditions by Thursday night. With this faster exit of
the cold front, the severe potential for Thursday afternoon/evening
should remain to the east across Missouri. Depending upon the timing
of the frontal passage, could see Thursday high temperatures ranging
from the low 60s to low 70s.
Friday afternoon through Saturday look to remain dry for the most
part with surface high pressure in control. Although a passing
shower could occur Saturday during the day, it looks like the chance
is very small with minimal moisture to work with. Saturday night
will set the stage for possibly a more active Sunday as moisture
advection will be underway as a low pressure trough further develops
over the Southern Rockies and begins to eject into the Southern and
Central Plains on Sunday morning. The best chance for thunderstorms
will be in the afternoon Sunday likely being the best near peak
heating as further destabilization of the boundary layer takes
shape. Timing on this event and any severe potential is uncertain
at this point as shear profiles and a few other key parameters don`t
seem to be overly impressive. As the overall system is progged to
be a bit slow moving, some showers could linger into Monday morning
as well.
Temperatures look to remain in mid 60s to 70s for highs and low
temperatures only reaching into the 40s and low 50s which is close to
normal for this time of year.
&&
.AVIATION...(For the 18Z TAFs through 18Z Tuesday Afternoon)
Issued at 1236 PM CDT MON APR 6 2015
The MVFR stratus that is in place over all terminals has been
dissipating more slowly than expected from the west. MHK may be
very close to where the stratus deck and clear skies meet later
this afternoon, but for now have kept them at MVFR based on
forecast soundings. Tonight, IFR cigs and visbys are expected
again accompanied by light drizzle. LIFR conditions overnight are
possible, but due to uncertainty in timing have kept them out of
this TAF package.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...Drake/Hennecke
AVIATION...Heller
AREA FORECAST DISCUSSION
NWS TOPEKA KS
623 AM CDT Mon Apr 6 2015
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 331 AM CDT MON APR 6 2015
08Z water vapor imagery shows a closed low off the coast of the
pacific northwest with a general southwesterly flow from
southern CA to the central plains. Aside from a few weak
perturbations within the flow, there is no obvious shortwave
immediately upstream of the forecast area. At the surface, moisture
has been on the return north between high pressure over the
southeastern U.S. and low pressure in the lee of the Rockies.
For today, the main questions to the forecast is whether the stratus
remains in place or if parts of central KS are able to clear out.
The 00Z NAM appears to be an outlier in that it keeps the main area
of low pressure further west over eastern CO while most all other
guidance brings the low further into KS and a surface trough with
some dry air into central KS. Because of this have leaned towards
the GFS/RAP solutions of scattering out the stratus across central
KS, but keeping it in across extreme eastern KS. This should favor a
strong temp gradient across the forecast area with lower 70s east
due to cloud cover and limited mixing while out around Abilene
should mix deeper with afternoon sunshine helping temps warm into
the lower 80s. All the models keep a stout elevated mixed layer over
the boundary layer today save for central KS where warming surface
temps could diminish the cap. However there does not look to be much
surface based instability along the trough axis as dry air from
aloft mixes to the surface. Since there is no obvious forcing
mechanism, think chances for afternoon thunderstorms is to low to
include a mention and some drizzle through the morning is about
all the sensible weather we`ll see today.
Tonight may be a different scenario as the trough axis or boundary
over the area helps to lift parcels as the low level jet increases.
Except for the NAM (which is not favored), models keep this feature
mainly across far northern KS. And then there is still somewhat of
an inversion to overcome. Because of this, think the better chances
for thunderstorms may end up being to the north and east of the
forecast area. This is also where the stronger theta-e advection if
progged to occur. Nevertheless have maintained some modest POPs as
it is difficult to rule out some showers and storms. Confidence in
the forecast is below average since there is such a fine line where
the boundary sets up and chances for precip. Think with low level
moisture remaining high across eastern KS overnight, that the
stratus could expand back west and south tonight. Lows south of the
boundary should be warm in the lower 60s with temps tapering off into
the mid 50s over north central KS.
.LONG TERM...(Tuesday through Sunday)
Issued at 331 AM CDT MON APR 6 2015
Main upper trough axis digs southeast over southern California
Tuesday, ejecting an embedded shortwave trough towards the northern
plains by Tuesday afternoon. Convection develops north and east over
Nebraska while the surface trough shifts eastward, forcing the
cold front southeast towards east central and southeast Kansas.
Details on how quickly stratus clears out ahead of the front to
dewpoints and available instability are still varying between
guidance. Forecast soundings at Chanute from the NAM and GFS erode
the capping inversion by early evening where sfc based CAPE is
somewhat varied due to the 10 degree dewpoint spread, but overall
2500 J/KG. Bulk shear is at 40 KTS from the southwest. Areas south
of Interstate 35 may still see the best chance for severe updrafts
forming with large hail and damaging winds. Activity may spread
further north overnight Tuesday aided by the veering low level jet however
believe elevated convection will be the primary mode for far eastern
Kansas.
Wednesday is still on track for the best chance of severe storms
to form somewhere across the region as strong height falls occur
with the approaching negatively tilted trough. Boundary is expected
to lift back north as a warm front, and the dryline shifts over
central Kansas by late afternoon. Much of the area should see
dewpoints around 60 degrees underneath a stratus deck during the
afternoon as highs warm to the upper 70s. With models having the
boundary progged near the Interstate 70 corridor, inhibition becomes
minimal with sfc CAPE approaching 2500 J/KG. Support from the wave
enhances effective shear in excess of 50 KTS, focusing development
near the Interstate 70 corridor and further west along the dryline.
Either way, supercells may develop over the area or lift northeast
into the area from the dry line. Large hail, damaging winds, and a
few tornadoes are all possible. Stay tuned for changes in the
forecast as this system currently would have a high impact on
northeast Kansas. Activity would quickly track northeast with the
sfc low overnight, with precip clearing eastward Thursday morning.
Guidance Thursday afternoon is beginning to trend the severe weather
threat a bit further east. While the previous ECMWF runs were trending
slower with the main trough axis compared to the GFS and GEM, latest
run is now tracking the sfc low and attendant dryline towards
western MO by late afternoon. This would keep the severe threat
further east as well with much of the area in mostly clear and dry
conditions. Have trended down precip chances some, especially
western areas, but wanted to keep a chance for thunderstorms over the
eastern half of the CWA in case models shift again. This may alter
temps as well which I currently have from the middle 60s in north
central Kansas, to the upper 70s in eastern Kansas.
The system exits Friday with sunny skies and gusty north winds
through the day. Temperatures fall back to the 60s before flow
pattern quickly transitions as a weak shortwave trough enters central
Kansas on Saturday. Kept the forecast dry for now, until a stronger
shortwave trough increases thunderstorm chances Saturday evening and
Sunday across much of the area.
&&
.AVIATION...(For the 12Z TAFs through 12Z Tuesday Morning)
Issued at 623 AM CDT MON APR 6 2015
Confidence in forecast is not that high as the 10Z RAP has trended
more in line with the NAM keeping at least MVFR CIGS over TOP and
FOE. Still think MHK should scatter out this afternoon. However
all the guidance shows the low CIGS moving back in by the late
evening with another chance for mist and drizzle. Forecast
soundings maintain a stout capping inversion over the boundary
layer with dry mid levels, so think chances for TS during the next
24 hours is to limited to include. Timing changes in VSBY and CIGS
is based on the NAM and RAP with diurnal tendencies in mind,
likely needing refinement as the day progresses.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1144 PM CDT Sun Apr 5 2015
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Monday)
Issued at 402 PM CDT SUN APR 5 2015
Tonight and Monday...the amplified upper level trough will begin to
approach the northern CA coast by 00Z TUE. A broad area of
southwesterly mid and upper level flow will spread northeast across
the plains states.
Through the evening hours deeper moisture will
spread northward across the CWA. Low stratus has already moved north
into the southeast counties and will spread northward through the
night. The NAM, GFS, RAP and members of the WRF models all show weak
isentropic lift developing at the 290K theta level. This may provide
for periods of light drizzle after midnight and into the mid morning
hours of Monday. I suppose if there is enough drizzle some areas
could see a couple hundredths of an inch of QPF from late Tonight
through the mid morning hours of Monday. Overnight lows will only
drop into the lower 50s, given the southerly winds and low-level
moisture advection through the night.
Monday, An elevated mix layer from the high plains will spread
across the CWA. This will cause a large capping inversion to form.
The forecast soundings show the EML will be at 840MB and the
moisture will only be as deep as 900mb, thus even taking the parcel
from the top of the moist layer would not break the cap.
Therefore, we will not see thunderstorms through the day on Monday.
We may not even see showers once the boundary layer mixes deep
enough to end the low-level isentropic lift and the drizzle chances.
Forecast soundings show the stratus holding for most of the day
across the eastern counties of the CWA. The western counties may
become partly cloudy to mostly sunny. There will most likely be a
rather sharp temperature gradient across the CWA with low to mid 80s
across the southwest counties and highs only reaching to near 70
degrees across the extreme eastern counties of the CWA. Southerly
surface winds will increase to 15 to 25 MPH with gusts of 30 to 35
MPH as a lee surface low deepens across western KS.
.LONG TERM...(Monday Night through Sunday)
Issued at 402 PM CDT SUN APR 5 2015
By Monday night, surface low pressure will be centered over central
Kansas with the dryline expected to track as far east as into
central Kansas with the associated warm front extending into
northeast Kansas. While most models show the surface low slowly
lifting northeast Monday night through Tuesday, there is uncertainty
with how long precipitation will stick around. At this time, the
better chances for precipitation should be focused along and north
of the warm front near the Kansas/Nebraska border, and then shift
into far eastern Kansas as the surface low tracks eastward. What the
models do agree with is a very strong cap being in place Monday
night through Tuesday with a decent amount of elevated CAPE.
However, model soundings show such shallow saturation in the low
levels that confidence is low in even elevated thunderstorms being
able to develop, but a few scattered showers may be possible. With
this system being so slow-moving, models show the associated frontal
boundary being draped across the northern part of the forecast area
by Tuesday morning, however there are model discrepancies with the
exact location. Expect strong southerly flow in the warm sector
Monday night along with partly to mostly cloudy skies, so overnight
low temperatures should be mild in the upper 50s to mid 60s.
However, locations north of the boundary should see a sharper
temperature gradient with lows in the low/mid 50s. This distinct
temperature gradient will continue through the day on Tuesday as
models show the boundary still lingering across the CWA. Once again,
the exact location of this gradient is uncertain due to model
discrepancies in the boundary location, however Tuesday high
temperatures may range from the middle 60s to low/mid 80s. This
boundary will finally shift east of the area Tuesday evening, but
models show the potential for some thunderstorms to develop along
this boundary late Tuesday afternoon into Tuesday evening as it
shifts east. However, the models are split on whether or not the cap
will be broken by then, with the NAM showing a strong cap while the
GFS/ECMWF show little to no cap. If the cap is able to weaken enough
to support thunderstorm development, there looks to be upwards of
around 2000 J/kg of CAPE with around 40kts of 0-6km bulk shear, so
some severe thunderstorms would be possible with large hail and
strong winds being the primary threats.
A much stronger system is expected by Wednesday/Wednesday night as
the mid-level trough that will move into the western U.S. on Tuesday
quickly advances into the Rockies by Wednesday and helps to push a
strong low pressure system into the region. Models show a warm front
associated with this next system draped across far southern Kansas
near the Oklahoma border by Wednesday morning, with the boundary
lifting northward into the forecast area Wednesday afternoon and
evening. However, there is uncertainty with how quickly this front
will surge northward and just how far north it will track. 12z model
runs showed the GFS/GEM tracking faster and further north while the
ECMWF/NAM were slower and thus limited on their northern extension.
While these details will need to be worked out in the coming days,
MUCAPE values may be upwards of at least 1500-2500 J/kg, 30-40+ kts
of 0-6km bulk shear, 0-1km helicity values around 150-250 m2/s2, and
limited CIN. As a result, supercellular thunderstorms are expected
with all severe threats possible -- large hail, damaging winds, as
well as some tornadoes possible. The temperature gradient will
continue through Wednesday with highs potentially ranging from mid
60s to mid 70s.
For Thursday, both GFS and ECMWF do indicate best potential for
thunderstorm activity to be in the afternoon into early evening.
However, the GFS does seem to be faster and progression is more
quickly to the North with a more negative tilt to the upper level
trough. This does create some uncertainty for how much and how long
the best conditions will exist for any severe threat over extreme
eastern KS. Any major activity looks to be East of Hwy 75 for the
most part as good moisture, shear and instability are better just
off to the East. During the mid to late afternoon time frame a jet
streak may also help to enhance storms along the cold front which
looks to be making its way through the very eastern portions of the
outlook area at this time. As a result, the focus for storms by early
evening does look to be more over western MO.
After the cold front makes its way through, more zonal flow sets up
with a quick transition into a more amplified ridge for Saturday
into Sunday morning in response to yet another potential trough
digging into the four corners region. This could bring some more
showers and potential thunderstorm activity later during the day
Sunday into evening to our area.
Temperatures for Thursday through the end of the period should be trending
on the pleasant side with highs in the upper 60s and lower 70s with
lows in the lower 40s initially but creeping up to the 50s by later
in the period.
&&
.AVIATION...(For the 06Z TAFs through 06Z Monday Night)
Issued at 1144 PM CDT SUN APR 5 2015
Observation and model trends pointing to MVFR ceilings dropping to
IFR around 06Z and continuing to lower in the next few hours,
though mixing should be enough to keep levels above VLIFR.
Challenges on how fast and how far ceilings rise in the later
portions of the forecast continue with differences in mixing of
the shallow moisture under the strong inversion aloft. GFS seems
to have handled recent conditions the best and have stayed closest
to it.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...Drake/Hennecke
AVIATION...65
AREA FORECAST DISCUSSION
NWS JACKSON KY
152 PM EDT MON APR 6 2015
.UPDATE...
ISSUED AT 1100 AM EDT MON APR 6 2015
AN AREA OF SHOWERS AND THUNDERSTORMS IS MOVING ACROSS THE SOUTHERN
AND SOUTHWESTERN PART OF THE CWA. THIS HAS MEASURED AT SOME OF THE
MESONET SITES NEAR THE TN BORDER AND AT KEKQ. THIS IS WEAKENING AS
IT MOVES FURTHER EAST INTO THE DRIER AIR AND IS TURNING MORE INTO
VIRGA OR SPRINKLES...BUT WILL GRADUALLY HELP TO SATURATE THE LOWER
LEVELS FROM THE TOP DOWN. THIS TREND SHOULD CONTINUE BASED ON
RECENT RADAR TRENDS AND SHORT TERM MODELS SUCH AS THE HRRR
SUGGESTING SOME ISOLATED MEASURABLE PRECIPITATION ACROSS THE
SOUTH OVER THE NEXT COUPLE OF HOURS WITH GENERALLY VIRGA AND
SPRINKLES. IN ADDITION...THERE HAVE BEEN SOME BREAKS OR THIN SPOTS
IN THE MID LEVEL DECK WHICH HAS ALLOWED SEVERAL LOCATIONS EAST OF
INTERSTATE 75 TO ALREADY RISE INTO THE 60S...IN SOME CASES THE MID
AND UPPER 60S. IN THOSE AREAS...TEMPERATURES WERE NEARING THE
PREVIOUSLY FORECAST MAX T. THIS COMBINED WITH THE SOUTHERLY
COMPONENT TO THE LOW LEVEL FLOW OFF THE HIGHER TERRAIN OF VA WILL
LEAD TO SEVERAL PLACES REACHING THE LOWER 70S THIS AFTERNOON.
ATTM...WE EXPECT THE AREA OF SHOWERS AND SOME EMBEDDED THUNDERSTORMS
NOW OVER WESTERN TN...SE MO AND NE AR TO MOVE EAST NORTHEAST INTO
THE SOUTHERN AND CENTRAL PART OF THE CWA AND TN VALLEY REGION DURING
THE AFTERNOON AND EVENING. POPS HAVE BEEN ADJUSTED ACCORDINGLY. SOME
ADDITIONAL SHOWERS AND SOME ISOLATED TO SCATTERED THUNDERSTORM
DEVELOPMENT MAY OCCUR ON THE LEADING EDGE OR QUASI DIFFERENTIAL
HEATING BOUNDARY DURING THE AFTERNOON TO EARLY EVENING HOURS.
UPDATED GRIDS AND ZFP HAVE ALREADY BEEN ISSUED.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 404 AM EDT MON APR 6 2015
A SHALLOW SHORTWAVE PASSING JUST TO OUR SOUTH...IN CONJUNCTION WITH
SOUTHERLY WINDS BEHIND A DEPARTING HIGH PRESSURE SYSTEM...HAVE LED
TO A SLOW INCREASE IN MOISTURE ACROSS THE REGION. OUR NEXT
CONCERN IS NOW ANOTHER SUBTLE SHORTWAVE...CURRENTLY DEVELOPING
OVER THE TEXARKANA REGION...WHICH WILL STRENGTHEN SLIGHTLY AS IT
SHIFTS EASTWARD THROUGHOUT THE DAY...REACHING JUST SOUTH OF THE
CWA BY 6Z TUESDAY.
AS THIS SHORTWAVE NEARS...EXPECT MOISTURE TO CONTINUE TO BUILD...AND
EVENTUALLY PRECIP TO WORK ITS WAY INTO THE REGION. MODELS CONTINUE
TO AGREE ON SLOWING DOWN THE TIMING OF ONSET...WITH QPF NOW LIKELY
TO REACH THE SW EXTENT OF THE CWA AFTER 12Z. IN FACT...THE LATEST
NAM12 AND HRRR HOLDS IT OFF EVEN LONGER...CLOSER TO 18Z.
HOWEVER...GIVEN SOME LIGHT RETURNS ALREADY SHOWING UP ON RADAR
ACROSS NORTH CENTRAL KY AND PORTIONS OF TN...EXPECT THAT ALL WE NEED
IS SOME DAYLIGHT AND HEATING TO GET THINGS GOING HERE. THE SAME
WILL GO WITH OVERNIGHT...WHEN WE LOSE SOME OF OUR DIURNAL HEATING.
EXPECT THE OVERALL COVERAGE TO GO DOWN BRIEFLY...UNTIL A WARM
FRONT TO OUR SOUTH AND STATIONARY FRONTAL ZONE CLOSE IN CLOSER ON
KY BETWEEN 6 AND 12Z TUESDAY. AT THIS POINT...EXPECT SHOWERS AND
POTENTIAL THUNDERSTORMS TO START UP ONCE MORE...EVEN BEFORE WE
RECEIVE THE INFLUENCE FROM DAYTIME HEATING...AND CONTINUE THROUGH
THE DAY TUESDAY.
WENT WITH A MODEL BLEND FOR POPS AND TIMING...LOWERING THEM
SLIGHTLY DURING THE OVERNIGHT HOURS TONIGHT FOR THE ABOVE
MENTIONED LOSS OF FORCING. UNFORTUNATELY...IN THIS TYPE OF SET
UP...GOOD ISENTROPIC LIFT AND UPPER LEVEL INSTABILITY WILL ENSURE
PRECIP WILL OCCUR...BUT THE EXACT LOCATION AND TIMING OF THIS
PRECIP IS STILL SOMEWHAT UNCERTAIN...AND DIFFERS FROM MODEL TO
MODEL. GIVEN THE LATEST NAM12 FORECAST SOUNDINGS...THE LEADING
EDGE OF THIS SYSTEM LOOKS TO HAVE VERY LITTLE INSTABILITY...SO
KEPT WITH ONLY RAIN CHANCES UNTIL THIS AFTERNOON WHEN NEAR SURFACE
TEMPS ARE ABLE TO WARM ENOUGH TO INCREASE THE LAPSE RATES. THE
BEST INSTABILITY WILL ACTUALLY BE DURING THE DAY TOMORROW AS THE
COLD FRONT TO OUR NORTH SINKS SOUTHWARD AND NEARS THE OHIO RIVER
VALLEY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 510 AM EDT MON APR 6 2015
THE MODELS ARE IN FAIRLY GOOD AGREEMENT ALOFT THROUGH THE
EXTENDED PORTION OF THE FORECAST. THEY ALL AGREE THAT A GRADUALLY
BUILDING UPPER RIDGE WILL DOMINATE THE SOUTHEASTERN PORTION OF
THE UNITED STATES INTO FRIDAY. THROUGH THIS RIDGE A STREAM OF
LOOSE ENERGY PACKETS WILL CROSS OVER KENTUCKY. THIS PROCESS WILL
BE JOINED BY THE ARRIVAL OF A DEEPER TROUGH MOVING EAST THROUGH
THE PLAINS BY THE END OF THE WEEK. THIS BRINGS HEIGHT FALLS AND A
MORE ORGANIZED CLUSTER OF ENERGY TO THE OHIO VALLEY BY FRIDAY
EVENING. THE TROUGH RESPONSIBLE FOR THIS WILL LIFT INTO THE GREAT
LAKES THAT NIGHT WITH A RESURGENCE TO THE SOUTHWEST IN THE ECMWF
ON SATURDAY DRAGGING MORE ENERGY SOUTH AND INTO KENTUCKY BEFORE
DEPARTING LATER THAT NIGHT. RISING HEIGHTS WILL FOLLOW FOR THE
AREA. THE GFS DOES NOT HAVE THIS RESURGENCE IN ITS SOLUTION SO
THIS DISCREPANCY LOWERS CONFIDENCE FOR THE LATTER PARTS OF THE
EXTENDED...NEVERTHELESS A GENERAL MODEL BLEND WAS FAVORED FOR
THIS PART OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE A WARM...WET...AND ACTIVE WEEK FOR
KENTUCKY AS THE STATE WILL BE BELOW A STALLED FRONTAL BOUNDARY
RUNNING THROUGH THE OHIO VALLEY FOR MUCH OF THE TIME. VARIOUS
UPPER WAVES AND SFC REFLECTIONS ALONG THIS BOUNDARY WILL KEEP A
THREAT OF SHOWERS AND THUNDERSTORMS GOING THROUGH MUCH OF THE
FORECAST INTO SATURDAY MORNING. THE RISK OF ORGANIZED AND MORE
THREATENING STORMS DEVELOPS LATER THURSDAY AND CONTINUES INTO
FRIDAY DUE TO THE HEIGHT FALLS AND MORE IMPRESSIVE ENERGY STREAM
TARGETING THE REGION...PARTICULARLY IN THE WEST. THE MAIN SFC LOW
LIFTS INTO THE GREAT LAKES ON FRIDAY WITH A SLOW MOVING COLD FRONT
PASSING THROUGH THE AREA FROM FRIDAY AFTERNOON INTO SATURDAY
MORNING. GIVEN THE OPEN GULF AND AVAILABLE MOISTURE...MODERATE TO
HEAVY RAINS WILL BE A THREAT FOR THE END OF THE WEEK. DRIER
WEATHER DOES FOLLOW FOR THE REST OF THE WEEKEND AS HIGH PRESSURE
BUILDS INTO THE MIDWEST AND OHIO VALLEY. THIS WILL ALSO BRING MORE
SEASONABLE TEMPERATURES TO THE STATE FOLLOWING A WEEK OF ABOVE
NORMAL WARMTH...WHERE SOME LOW 80S WILL LIKELY BE SEEN...DESPITE
THE OCCASIONAL RAIN.
THE CR GRID BLEND CAME IN REASONABLY WELL WITH JUST SOME MINOR
ADJUSTMENTS MADE TO POPS TO BETTER REFLECT A DIURNAL TREND. ALSO
MADE SOME TERRAIN BASED ADJUSTMENTS TO TEMPS EACH NIGHT THROUGH
FRIDAY MORNING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 152 PM EDT MON APR 6 2015
THERE ARE A FEW LINGERING MORNING SHOWERS THAT ARE EXITING KY TO
THE EAST. BACK TO THE WEST...A LARGER AREA OF RAIN IS STARTING TO
MOVE INTO CENTRAL KY AND IS EXPECTED TO IMPACT SOUTHEASTERN KY BY
LATER THIS EVENING. THERE IS ALSO A CHANCE FOR ADDITIONAL
SHOWERS/THUNDERSTORMS TO FORM THIS AFTERNOON. THE EXACT TIMING AND
LOCATION OF THESE SHOWERS AND THUNDERSTORMS...AS WELL AS WHEN OR
IF THEY WILL IMPACT A SPECIFIC TAF SITE...IS STILL UNCERTAIN. SO
HAVE GENERALLY LOWERED CIGS THROUGH THE LATE EVENING AND OVERNIGHT
HOURS...EVENTUALLY REACHING MVFR STATUS...AS RAIN
SHOWERS/THUNDERSTORMS POTENTIALLY MOVES THROUGH OUR AREA AND HELPS
SATURATE THE COLUMN. VIS IS ALSO LIKELY TO BE RESTRICTED DURING
ANY RAIN SHOWERS/THUNDERSTORMS...BUT WILL ULTIMATELY DEPEND ON THE
STRENGTH OF THE SHOWERS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...JMW
LONG TERM...GREIF
AVIATION...JVM
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1104 AM EDT MON APR 6 2015
.UPDATE...
ISSUED AT 1100 AM EDT MON APR 6 2015
AN AREA OF SHOWERS AND THUNDERSTORMS IS MOVING ACROSS THE SOUTHERN
AND SOUTHWESTERN PART OF THE CWA. THIS HAS MEASURED AT SOME OF THE
MESONET SITES NEAR THE TN BORDER AND AT KEKQ. THIS IS WEAKENING AS
IT MOVES FURTHER EAST INTO THE DRIER AIR AND IS TURNING MORE INTO
VIRGA OR SPRINKLES...BUT WILL GRADUALLY HELP TO SATURATE THE LOWER
LEVELS FROM THE TOP DOWN. THIS TREND SHOULD CONTINUE BASED ON
RECENT RADAR TRENDS AND SHORT TERM MODELS SUCH AS THE HRRR
SUGGESTING SOME ISOLATED MEASURABLE PRECIPITATION ACROSS THE
SOUTH OVER THE NEXT COUPLE OF HOURS WITH GENERALLY VIRGA AND
SPRINKLES. IN ADDITION...THERE HAVE BEEN SOME BREAKS OR THIN SPOTS
IN THE MID LEVEL DECK WHICH HAS ALLOWED SEVERAL LOCATIONS EAST OF
INTERSTATE 75 TO ALREADY RISE INTO THE 60S...IN SOME CASES THE MID
AND UPPER 60S. IN THOSE AREAS...TEMPERATURES WERE NEARING THE
PREVIOUSLY FORECAST MAX T. THIS COMBINED WITH THE SOUTHERLY
COMPONENT TO THE LOW LEVEL FLOW OFF THE HIGHER TERRAIN OF VA WILL
LEAD TO SEVERAL PLACES REACHING THE LOWER 70S THIS AFTERNOON.
ATTM...WE EXPECT THE AREA OF SHOWERS AND SOME EMBEDDED THUNDERSTORMS
NOW OVER WESTERN TN...SE MO AND NE AR TO MOVE EAST NORTHEAST INTO
THE SOUTHERN AND CENTRAL PART OF THE CWA AND TN VALLEY REGION DURING
THE AFTERNOON AND EVENING. POPS HAVE BEEN ADJUSTED ACCORDINGLY. SOME
ADDITIONAL SHOWERS AND SOME ISOLATED TO SCATTERED THUNDERSTORM
DEVELOPMENT MAY OCCUR ON THE LEADING EDGE OR QUASI DIFFERENTIAL
HEATING BOUNDARY DURING THE AFTERNOON TO EARLY EVENING HOURS.
UPDATED GRIDS AND ZFP HAVE ALREADY BEEN ISSUED.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 404 AM EDT MON APR 6 2015
A SHALLOW SHORTWAVE PASSING JUST TO OUR SOUTH...IN CONJUNCTION WITH
SOUTHERLY WINDS BEHIND A DEPARTING HIGH PRESSURE SYSTEM...HAVE LED
TO A SLOW INCREASE IN MOISTURE ACROSS THE REGION. OUR NEXT
CONCERN IS NOW ANOTHER SUBTLE SHORTWAVE...CURRENTLY DEVELOPING
OVER THE TEXARKANA REGION...WHICH WILL STRENGTHEN SLIGHTLY AS IT
SHIFTS EASTWARD THROUGHOUT THE DAY...REACHING JUST SOUTH OF THE
CWA BY 6Z TUESDAY.
AS THIS SHORTWAVE NEARS...EXPECT MOISTURE TO CONTINUE TO BUILD...AND
EVENTUALLY PRECIP TO WORK ITS WAY INTO THE REGION. MODELS CONTINUE
TO AGREE ON SLOWING DOWN THE TIMING OF ONSET...WITH QPF NOW LIKELY
TO REACH THE SW EXTENT OF THE CWA AFTER 12Z. IN FACT...THE LATEST
NAM12 AND HRRR HOLDS IT OFF EVEN LONGER...CLOSER TO 18Z.
HOWEVER...GIVEN SOME LIGHT RETURNS ALREADY SHOWING UP ON RADAR
ACROSS NORTH CENTRAL KY AND PORTIONS OF TN...EXPECT THAT ALL WE NEED
IS SOME DAYLIGHT AND HEATING TO GET THINGS GOING HERE. THE SAME
WILL GO WITH OVERNIGHT...WHEN WE LOSE SOME OF OUR DIURNAL HEATING.
EXPECT THE OVERALL COVERAGE TO GO DOWN BRIEFLY...UNTIL A WARM
FRONT TO OUR SOUTH AND STATIONARY FRONTAL ZONE CLOSE IN CLOSER ON
KY BETWEEN 6 AND 12Z TUESDAY. AT THIS POINT...EXPECT SHOWERS AND
POTENTIAL THUNDERSTORMS TO START UP ONCE MORE...EVEN BEFORE WE
RECEIVE THE INFLUENCE FROM DAYTIME HEATING...AND CONTINUE THROUGH
THE DAY TUESDAY.
WENT WITH A MODEL BLEND FOR POPS AND TIMING...LOWERING THEM
SLIGHTLY DURING THE OVERNIGHT HOURS TONIGHT FOR THE ABOVE
MENTIONED LOSS OF FORCING. UNFORTUNATELY...IN THIS TYPE OF SET
UP...GOOD ISENTROPIC LIFT AND UPPER LEVEL INSTABILITY WILL ENSURE
PRECIP WILL OCCUR...BUT THE EXACT LOCATION AND TIMING OF THIS
PRECIP IS STILL SOMEWHAT UNCERTAIN...AND DIFFERS FROM MODEL TO
MODEL. GIVEN THE LATEST NAM12 FORECAST SOUNDINGS...THE LEADING
EDGE OF THIS SYSTEM LOOKS TO HAVE VERY LITTLE INSTABILITY...SO
KEPT WITH ONLY RAIN CHANCES UNTIL THIS AFTERNOON WHEN NEAR SURFACE
TEMPS ARE ABLE TO WARM ENOUGH TO INCREASE THE LAPSE RATES. THE
BEST INSTABILITY WILL ACTUALLY BE DURING THE DAY TOMORROW AS THE
COLD FRONT TO OUR NORTH SINKS SOUTHWARD AND NEARS THE OHIO RIVER
VALLEY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 510 AM EDT MON APR 6 2015
THE MODELS ARE IN FAIRLY GOOD AGREEMENT ALOFT THROUGH THE
EXTENDED PORTION OF THE FORECAST. THEY ALL AGREE THAT A GRADUALLY
BUILDING UPPER RIDGE WILL DOMINATE THE SOUTHEASTERN PORTION OF
THE UNITED STATES INTO FRIDAY. THROUGH THIS RIDGE A STREAM OF
LOOSE ENERGY PACKETS WILL CROSS OVER KENTUCKY. THIS PROCESS WILL
BE JOINED BY THE ARRIVAL OF A DEEPER TROUGH MOVING EAST THROUGH
THE PLAINS BY THE END OF THE WEEK. THIS BRINGS HEIGHT FALLS AND A
MORE ORGANIZED CLUSTER OF ENERGY TO THE OHIO VALLEY BY FRIDAY
EVENING. THE TROUGH RESPONSIBLE FOR THIS WILL LIFT INTO THE GREAT
LAKES THAT NIGHT WITH A RESURGENCE TO THE SOUTHWEST IN THE ECMWF
ON SATURDAY DRAGGING MORE ENERGY SOUTH AND INTO KENTUCKY BEFORE
DEPARTING LATER THAT NIGHT. RISING HEIGHTS WILL FOLLOW FOR THE
AREA. THE GFS DOES NOT HAVE THIS RESURGENCE IN ITS SOLUTION SO
THIS DISCREPANCY LOWERS CONFIDENCE FOR THE LATTER PARTS OF THE
EXTENDED...NEVERTHELESS A GENERAL MODEL BLEND WAS FAVORED FOR
THIS PART OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE A WARM...WET...AND ACTIVE WEEK FOR
KENTUCKY AS THE STATE WILL BE BELOW A STALLED FRONTAL BOUNDARY
RUNNING THROUGH THE OHIO VALLEY FOR MUCH OF THE TIME. VARIOUS
UPPER WAVES AND SFC REFLECTIONS ALONG THIS BOUNDARY WILL KEEP A
THREAT OF SHOWERS AND THUNDERSTORMS GOING THROUGH MUCH OF THE
FORECAST INTO SATURDAY MORNING. THE RISK OF ORGANIZED AND MORE
THREATENING STORMS DEVELOPS LATER THURSDAY AND CONTINUES INTO
FRIDAY DUE TO THE HEIGHT FALLS AND MORE IMPRESSIVE ENERGY STREAM
TARGETING THE REGION...PARTICULARLY IN THE WEST. THE MAIN SFC LOW
LIFTS INTO THE GREAT LAKES ON FRIDAY WITH A SLOW MOVING COLD FRONT
PASSING THROUGH THE AREA FROM FRIDAY AFTERNOON INTO SATURDAY
MORNING. GIVEN THE OPEN GULF AND AVAILABLE MOISTURE...MODERATE TO
HEAVY RAINS WILL BE A THREAT FOR THE END OF THE WEEK. DRIER
WEATHER DOES FOLLOW FOR THE REST OF THE WEEKEND AS HIGH PRESSURE
BUILDS INTO THE MIDWEST AND OHIO VALLEY. THIS WILL ALSO BRING MORE
SEASONABLE TEMPERATURES TO THE STATE FOLLOWING A WEEK OF ABOVE
NORMAL WARMTH...WHERE SOME LOW 80S WILL LIKELY BE SEEN...DESPITE
THE OCCASIONAL RAIN.
THE CR GRID BLEND CAME IN REASONABLY WELL WITH JUST SOME MINOR
ADJUSTMENTS MADE TO POPS TO BETTER REFLECT A DIURNAL TREND. ALSO
MADE SOME TERRAIN BASED ADJUSTMENTS TO TEMPS EACH NIGHT THROUGH
FRIDAY MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 733 AM EDT MON APR 6 2015
A WEAK SHORTWAVE PASSING TO OUR SOUTH WILL CONTINUE TO SPARK
SHOWERS AND EVENTUALLY THUNDERSTORMS AS WE HEAD THROUGHOUT THE
DAY. EXPECT COVERAGE TO INCREASE BY THIS AFTERNOON. THE EXACT
TIMING AND LOCATION OF THESE SHOWERS AND THUNDERSTORMS...AS WELL
AS WHEN OR IF THEY WILL IMPACT A SPECIFIC TAF SITE...IS STILL IN
LOW CONFIDENCE...SO TRIED TO KEEP GENERALIZED IN TAFS. BY
OVERNIGHT...LOSS OF DAYTIME HEATING AND SHORTWAVE ENERGY MOVING
EAST OF THE REGION...WILL SUPPRESS SOME OF THE COVERAGE ACROSS
EASTERN KY. CIGS WILL SLOWLY LOWER THROUGHOUT THE TAF
PERIOD...LIKELY REACHING MVFR STATUS BY THIS EVENING AND THROUGH
THE OVERNIGHT. VIS WILL ALSO LIKELY BE RESTRICTED DURING ANY RAIN
SHOWERS/THUNDERSTORMS...BUT ULTIMATELY WILL FLUCTUATE DEPENDING
ON THE STRENGTH OF THE SHOWERS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...JMW
LONG TERM...GREIF
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
733 AM EDT MON APR 6 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 404 AM EDT MON APR 6 2015
A SHALLOW SHORTWAVE PASSING JUST TO OUR SOUTH...IN CONJUNCTION WITH
SOUTHERLY WINDS BEHIND A DEPARTING HIGH PRESSURE SYSTEM...HAVE LED
TO A SLOW INCREASE IN MOISTURE ACROSS THE REGION. OUR NEXT
CONCERN IS NOW ANOTHER SUBTLE SHORTWAVE...CURRENTLY DEVELOPING
OVER THE TEXARKANA REGION...WHICH WILL STRENGTHEN SLIGHTLY AS IT
SHIFTS EASTWARD THROUGHOUT THE DAY...REACHING JUST SOUTH OF THE
CWA BY 6Z TUESDAY.
AS THIS SHORTWAVE NEARS...EXPECT MOISTURE TO CONTINUE TO BUILD...AND
EVENTUALLY PRECIP TO WORK ITS WAY INTO THE REGION. MODELS CONTINUE
TO AGREE ON SLOWING DOWN THE TIMING OF ONSET...WITH QPF NOW LIKELY
TO REACH THE SW EXTENT OF THE CWA AFTER 12Z. IN FACT...THE LATEST
NAM12 AND HRRR HOLDS IT OFF EVEN LONGER...CLOSER TO 18Z.
HOWEVER...GIVEN SOME LIGHT RETURNS ALREADY SHOWING UP ON RADAR
ACROSS NORTH CENTRAL KY AND PORTIONS OF TN...EXPECT THAT ALL WE NEED
IS SOME DAYLIGHT AND HEATING TO GET THINGS GOING HERE. THE SAME
WILL GO WITH OVERNIGHT...WHEN WE LOSE SOME OF OUR DIURNAL HEATING.
EXPECT THE OVERALL COVERAGE TO GO DOWN BRIEFLY...UNTIL A WARM
FRONT TO OUR SOUTH AND STATIONARY FRONTAL ZONE CLOSE IN CLOSER ON
KY BETWEEN 6 AND 12Z TUESDAY. AT THIS POINT...EXPECT SHOWERS AND
POTENTIAL THUNDERSTORMS TO START UP ONCE MORE...EVEN BEFORE WE
RECEIVE THE INFLUENCE FROM DAYTIME HEATING...AND CONTINUE THROUGH
THE DAY TUESDAY.
WENT WITH A MODEL BLEND FOR POPS AND TIMING...LOWERING THEM
SLIGHTLY DURING THE OVERNIGHT HOURS TONIGHT FOR THE ABOVE
MENTIONED LOSS OF FORCING. UNFORTUNATELY...IN THIS TYPE OF SET
UP...GOOD ISENTROPIC LIFT AND UPPER LEVEL INSTABILITY WILL ENSURE
PRECIP WILL OCCUR...BUT THE EXACT LOCATION AND TIMING OF THIS
PRECIP IS STILL SOMEWHAT UNCERTAIN...AND DIFFERS FROM MODEL TO
MODEL. GIVEN THE LATEST NAM12 FORECAST SOUNDINGS...THE LEADING
EDGE OF THIS SYSTEM LOOKS TO HAVE VERY LITTLE INSTABILITY...SO
KEPT WITH ONLY RAIN CHANCES UNTIL THIS AFTERNOON WHEN NEAR SURFACE
TEMPS ARE ABLE TO WARM ENOUGH TO INCREASE THE LAPSE RATES. THE
BEST INSTABILITY WILL ACTUALLY BE DURING THE DAY TOMORROW AS THE
COLD FRONT TO OUR NORTH SINKS SOUTHWARD AND NEARS THE OHIO RIVER
VALLEY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 510 AM EDT MON APR 6 2015
THE MODELS ARE IN FAIRLY GOOD AGREEMENT ALOFT THROUGH THE
EXTENDED PORTION OF THE FORECAST. THEY ALL AGREE THAT A GRADUALLY
BUILDING UPPER RIDGE WILL DOMINATE THE SOUTHEASTERN PORTION OF
THE UNITED STATES INTO FRIDAY. THROUGH THIS RIDGE A STREAM OF
LOOSE ENERGY PACKETS WILL CROSS OVER KENTUCKY. THIS PROCESS WILL
BE JOINED BY THE ARRIVAL OF A DEEPER TROUGH MOVING EAST THROUGH
THE PLAINS BY THE END OF THE WEEK. THIS BRINGS HEIGHT FALLS AND A
MORE ORGANIZED CLUSTER OF ENERGY TO THE OHIO VALLEY BY FRIDAY
EVENING. THE TROUGH RESPONSIBLE FOR THIS WILL LIFT INTO THE GREAT
LAKES THAT NIGHT WITH A RESURGENCE TO THE SOUTHWEST IN THE ECMWF
ON SATURDAY DRAGGING MORE ENERGY SOUTH AND INTO KENTUCKY BEFORE
DEPARTING LATER THAT NIGHT. RISING HEIGHTS WILL FOLLOW FOR THE
AREA. THE GFS DOES NOT HAVE THIS RESURGENCE IN ITS SOLUTION SO
THIS DISCREPANCY LOWERS CONFIDENCE FOR THE LATTER PARTS OF THE
EXTENDED...NEVERTHELESS A GENERAL MODEL BLEND WAS FAVORED FOR
THIS PART OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE A WARM...WET...AND ACTIVE WEEK FOR
KENTUCKY AS THE STATE WILL BE BELOW A STALLED FRONTAL BOUNDARY
RUNNING THROUGH THE OHIO VALLEY FOR MUCH OF THE TIME. VARIOUS
UPPER WAVES AND SFC REFLECTIONS ALONG THIS BOUNDARY WILL KEEP A
THREAT OF SHOWERS AND THUNDERSTORMS GOING THROUGH MUCH OF THE
FORECAST INTO SATURDAY MORNING. THE RISK OF ORGANIZED AND MORE
THREATENING STORMS DEVELOPS LATER THURSDAY AND CONTINUES INTO
FRIDAY DUE TO THE HEIGHT FALLS AND MORE IMPRESSIVE ENERGY STREAM
TARGETING THE REGION...PARTICULARLY IN THE WEST. THE MAIN SFC LOW
LIFTS INTO THE GREAT LAKES ON FRIDAY WITH A SLOW MOVING COLD FRONT
PASSING THROUGH THE AREA FROM FRIDAY AFTERNOON INTO SATURDAY
MORNING. GIVEN THE OPEN GULF AND AVAILABLE MOISTURE...MODERATE TO
HEAVY RAINS WILL BE A THREAT FOR THE END OF THE WEEK. DRIER
WEATHER DOES FOLLOW FOR THE REST OF THE WEEKEND AS HIGH PRESSURE
BUILDS INTO THE MIDWEST AND OHIO VALLEY. THIS WILL ALSO BRING MORE
SEASONABLE TEMPERATURES TO THE STATE FOLLOWING A WEEK OF ABOVE
NORMAL WARMTH...WHERE SOME LOW 80S WILL LIKELY BE SEEN...DESPITE
THE OCCASIONAL RAIN.
THE CR GRID BLEND CAME IN REASONABLY WELL WITH JUST SOME MINOR
ADJUSTMENTS MADE TO POPS TO BETTER REFLECT A DIURNAL TREND. ALSO
MADE SOME TERRAIN BASED ADJUSTMENTS TO TEMPS EACH NIGHT THROUGH
FRIDAY MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 733 AM EDT MON APR 6 2015
A WEAK SHORTWAVE PASSING TO OUR SOUTH WILL CONTINUE TO SPARK
SHOWERS AND EVENTUALLY THUNDERSTORMS AS WE HEAD THROUGHOUT THE
DAY. EXPECT COVERAGE TO INCREASE BY THIS AFTERNOON. THE EXACT
TIMING AND LOCATION OF THESE SHOWERS AND THUNDERSTORMS...AS WELL
AS WHEN OR IF THEY WILL IMPACT A SPECIFIC TAF SITE...IS STILL IN
LOW CONFIDENCE...SO TRIED TO KEEP GENERALIZED IN TAFS. BY
OVERNIGHT...LOSS OF DAYTIME HEATING AND SHORTWAVE ENERGY MOVING
EAST OF THE REGION...WILL SUPPRESS SOME OF THE COVERAGE ACROSS
EASTERN KY. CIGS WILL SLOWLY LOWER THROUGHOUT THE TAF
PERIOD...LIKELY REACHING MVFR STATUS BY THIS EVENING AND THROUGH
THE OVERNIGHT. VIS WILL ALSO LIKELY BE RESTRICTED DURING ANY RAIN
SHOWERS/THUNDERSTORMS...BUT ULTIMATELY WILL FLUCTUATE DEPENDING
ON THE STRENGTH OF THE SHOWERS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JMW
LONG TERM...GREIF
AVIATION...JMW
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
510 AM EDT MON APR 6 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 404 AM EDT MON APR 6 2015
A SHALLOW SHORTWAVE PASSING JUST TO OUR SOUTH...IN CONJUNCTION WITH
SOUTHERLY WINDS BEHIND A DEPARTING HIGH PRESSURE SYSTEM...HAVE LED
TO A SLOW INCREASE IN MOISTURE ACROSS THE REGION. OUR NEXT
CONCERN IS NOW ANOTHER SUBTLE SHORTWAVE...CURRENTLY DEVELOPING
OVER THE TEXARKANA REGION...WHICH WILL STRENGTHEN SLIGHTLY AS IT
SHIFTS EASTWARD THROUGHOUT THE DAY...REACHING JUST SOUTH OF THE
CWA BY 6Z TUESDAY.
AS THIS SHORTWAVE NEARS...EXPECT MOISTURE TO CONTINUE TO BUILD...AND
EVENTUALLY PRECIP TO WORK ITS WAY INTO THE REGION. MODELS CONTINUE
TO AGREE ON SLOWING DOWN THE TIMING OF ONSET...WITH QPF NOW LIKELY
TO REACH THE SW EXTENT OF THE CWA AFTER 12Z. IN FACT...THE LATEST
NAM12 AND HRRR HOLDS IT OFF EVEN LONGER...CLOSER TO 18Z.
HOWEVER...GIVEN SOME LIGHT RETURNS ALREADY SHOWING UP ON RADAR
ACROSS NORTH CENTRAL KY AND PORTIONS OF TN...EXPECT THAT ALL WE NEED
IS SOME DAYLIGHT AND HEATING TO GET THINGS GOING HERE. THE SAME
WILL GO WITH OVERNIGHT...WHEN WE LOSE SOME OF OUR DIURNAL HEATING.
EXPECT THE OVERALL COVERAGE TO GO DOWN BRIEFLY...UNTIL A WARM
FRONT TO OUR SOUTH AND STATIONARY FRONTAL ZONE CLOSE IN CLOSER ON
KY BETWEEN 6 AND 12Z TUESDAY. AT THIS POINT...EXPECT SHOWERS AND
POTENTIAL THUNDERSTORMS TO START UP ONCE MORE...EVEN BEFORE WE
RECEIVE THE INFLUENCE FROM DAYTIME HEATING...AND CONTINUE THROUGH
THE DAY TUESDAY.
WENT WITH A MODEL BLEND FOR POPS AND TIMING...LOWERING THEM
SLIGHTLY DURING THE OVERNIGHT HOURS TONIGHT FOR THE ABOVE
MENTIONED LOSS OF FORCING. UNFORTUNATELY...IN THIS TYPE OF SET
UP...GOOD ISENTROPIC LIFT AND UPPER LEVEL INSTABILITY WILL ENSURE
PRECIP WILL OCCUR...BUT THE EXACT LOCATION AND TIMING OF THIS
PRECIP IS STILL SOMEWHAT UNCERTAIN...AND DIFFERS FROM MODEL TO
MODEL. GIVEN THE LATEST NAM12 FORECAST SOUNDINGS...THE LEADING
EDGE OF THIS SYSTEM LOOKS TO HAVE VERY LITTLE INSTABILITY...SO
KEPT WITH ONLY RAIN CHANCES UNTIL THIS AFTERNOON WHEN NEAR SURFACE
TEMPS ARE ABLE TO WARM ENOUGH TO INCREASE THE LAPSE RATES. THE
BEST INSTABILITY WILL ACTUALLY BE DURING THE DAY TOMORROW AS THE
COLD FRONT TO OUR NORTH SINKS SOUTHWARD AND NEARS THE OHIO RIVER
VALLEY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 510 AM EDT MON APR 6 2015
THE MODELS ARE IN FAIRLY GOOD AGREEMENT ALOFT THROUGH THE
EXTENDED PORTION OF THE FORECAST. THEY ALL AGREE THAT A GRADUALLY
BUILDING UPPER RIDGE WILL DOMINATE THE SOUTHEASTERN PORTION OF
THE UNITED STATES INTO FRIDAY. THROUGH THIS RIDGE A STREAM OF
LOOSE ENERGY PACKETS WILL CROSS OVER KENTUCKY. THIS PROCESS WILL
BE JOINED BY THE ARRIVAL OF A DEEPER TROUGH MOVING EAST THROUGH
THE PLAINS BY THE END OF THE WEEK. THIS BRINGS HEIGHT FALLS AND A
MORE ORGANIZED CLUSTER OF ENERGY TO THE OHIO VALLEY BY FRIDAY
EVENING. THE TROUGH RESPONSIBLE FOR THIS WILL LIFT INTO THE GREAT
LAKES THAT NIGHT WITH A RESURGENCE TO THE SOUTHWEST IN THE ECMWF
ON SATURDAY DRAGGING MORE ENERGY SOUTH AND INTO KENTUCKY BEFORE
DEPARTING LATER THAT NIGHT. RISING HEIGHTS WILL FOLLOW FOR THE
AREA. THE GFS DOES NOT HAVE THIS RESURGENCE IN ITS SOLUTION SO
THIS DISCREPANCY LOWERS CONFIDENCE FOR THE LATTER PARTS OF THE
EXTENDED...NEVERTHELESS A GENERAL MODEL BLEND WAS FAVORED FOR
THIS PART OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE A WARM...WET...AND ACTIVE WEEK FOR
KENTUCKY AS THE STATE WILL BE BELOW A STALLED FRONTAL BOUNDARY
RUNNING THROUGH THE OHIO VALLEY FOR MUCH OF THE TIME. VARIOUS
UPPER WAVES AND SFC REFLECTIONS ALONG THIS BOUNDARY WILL KEEP A
THREAT OF SHOWERS AND THUNDERSTORMS GOING THROUGH MUCH OF THE
FORECAST INTO SATURDAY MORNING. THE RISK OF ORGANIZED AND MORE
THREATENING STORMS DEVELOPS LATER THURSDAY AND CONTINUES INTO
FRIDAY DUE TO THE HEIGHT FALLS AND MORE IMPRESSIVE ENERGY STREAM
TARGETING THE REGION...PARTICULARLY IN THE WEST. THE MAIN SFC LOW
LIFTS INTO THE GREAT LAKES ON FRIDAY WITH A SLOW MOVING COLD FRONT
PASSING THROUGH THE AREA FROM FRIDAY AFTERNOON INTO SATURDAY
MORNING. GIVEN THE OPEN GULF AND AVAILABLE MOISTURE...MODERATE TO
HEAVY RAINS WILL BE A THREAT FOR THE END OF THE WEEK. DRIER
WEATHER DOES FOLLOW FOR THE REST OF THE WEEKEND AS HIGH PRESSURE
BUILDS INTO THE MIDWEST AND OHIO VALLEY. THIS WILL ALSO BRING MORE
SEASONABLE TEMPERATURES TO THE STATE FOLLOWING A WEEK OF ABOVE
NORMAL WARMTH...WHERE SOME LOW 80S WILL LIKELY BE SEEN...DESPITE
THE OCCASIONAL RAIN.
THE CR GRID BLEND CAME IN REASONABLY WELL WITH JUST SOME MINOR
ADJUSTMENTS MADE TO POPS TO BETTER REFLECT A DIURNAL TREND. ALSO
MADE SOME TERRAIN BASED ADJUSTMENTS TO TEMPS EACH NIGHT THROUGH
FRIDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 126 AM EDT MON APR 6 2015
VFR CONDITIONS WILL HOLD ON THROUGH THE NIGHT...ALTHOUGH CEILINGS
WILL BE LOWERING WITH TIME. SOME SHOWER ACTIVITY WILL THREATEN
TOWARDS DAWN FROM SOUTHWEST TO NORTHEAST. SHOWERS WILL INCREASE IN
AREAL COVERAGE DURING THE DAY...WITH EVEN A FEW THUNDERSTORMS
POSSIBLE DURING PEAK HEATING. CEILINGS WILL EVENTUALLY LOWER TO
MVFR NEAR AND WEST OF I-75 BY NIGHTFALL...WITH A BIT LESS
UNCERTAINTY TO THE EAST...WHERE LOW END VFR MAY HANG ON. WINDS
WILL RANGE FROM 5 TO 10 KTS THROUGH THE PERIOD...GENERALLY OUT OF
THE SOUTH.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JMW
LONG TERM...GREIF
AVIATION...GEOGERIAN/JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
410 AM EDT MON APR 6 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 404 AM EDT MON APR 6 2015
A SHALLOW SHORTWAVE PASSING JUST TO OUR SOUTH...IN CONJUNCTION WITH
SOUTHERLY WINDS BEHIND A DEPARTING HIGH PRESSURE SYSTEM...HAVE LED
TO A SLOW INCREASE IN MOISTURE ACROSS THE REGION. OUR NEXT
CONCERN IS NOW ANOTHER SUBTLE SHORTWAVE...CURRENTLY DEVELOPING
OVER THE TEXARKANA REGION...WHICH WILL STRENGTHEN SLIGHTLY AS IT
SHIFTS EASTWARD THROUGHOUT THE DAY...REACHING JUST SOUTH OF THE
CWA BY 6Z TUESDAY.
AS THIS SHORTWAVE NEARS...EXPECT MOISTURE TO CONTINUE TO BUILD...AND
EVENTUALLY PRECIP TO WORK ITS WAY INTO THE REGION. MODELS CONTINUE
TO AGREE ON SLOWING DOWN THE TIMING OF ONSET...WITH QPF NOW LIKELY
TO REACH THE SW EXTENT OF THE CWA AFTER 12Z. IN FACT...THE LATEST
NAM12 AND HRRR HOLDS IT OFF EVEN LONGER...CLOSER TO 18Z.
HOWEVER...GIVEN SOME LIGHT RETURNS ALREADY SHOWING UP ON RADAR
ACROSS NORTH CENTRAL KY AND PORTIONS OF TN...EXPECT THAT ALL WE NEED
IS SOME DAYLIGHT AND HEATING TO GET THINGS GOING HERE. THE SAME
WILL GO WITH OVERNIGHT...WHEN WE LOSE SOME OF OUR DIURNAL HEATING.
EXPECT THE OVERALL COVERAGE TO GO DOWN BRIEFLY...UNTIL A WARM
FRONT TO OUR SOUTH AND STATIONARY FRONTAL ZONE CLOSE IN CLOSER ON
KY BETWEEN 6 AND 12Z TUESDAY. AT THIS POINT...EXPECT SHOWERS AND
POTENTIAL THUNDERSTORMS TO START UP ONCE MORE...EVEN BEFORE WE
RECEIVE THE INFLUENCE FROM DAYTIME HEATING...AND CONTINUE THROUGH
THE DAY TUESDAY.
WENT WITH A MODEL BLEND FOR POPS AND TIMING...LOWERING THEM
SLIGHTLY DURING THE OVERNIGHT HOURS TONIGHT FOR THE ABOVE
MENTIONED LOSS OF FORCING. UNFORTUNATELY...IN THIS TYPE OF SET
UP...GOOD ISENTROPIC LIFT AND UPPER LEVEL INSTABILITY WILL ENSURE
PRECIP WILL OCCUR...BUT THE EXACT LOCATION AND TIMING OF THIS
PRECIP IS STILL SOMEWHAT UNCERTAIN...AND DIFFERS FROM MODEL TO
MODEL. GIVEN THE LATEST NAM12 FORECAST SOUNDINGS...THE LEADING
EDGE OF THIS SYSTEM LOOKS TO HAVE VERY LITTLE INSTABILITY...SO
KEPT WITH ONLY RAIN CHANCES UNTIL THIS AFTERNOON WHEN NEAR SURFACE
TEMPS ARE ABLE TO WARM ENOUGH TO INCREASE THE LAPSE RATES. THE
BEST INSTABILITY WILL ACTUALLY BE DURING THE DAY TOMORROW AS THE
COLD FRONT TO OUR NORTH SINKS SOUTHWARD AND NEARS THE OHIO RIVER
VALLEY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 426 PM EDT SUN APR 5 2015
THERE IS MODEL AGREEMENT FOR THE FIRST FEW DAYS OF THE PERIOD...BUT
THE ECMWF AND GFS THEN BEGIN TO SHOW MUCH MORE SIGNIFICANT
DIFFERENCES AS TIME PROGRESSES INTO THE WEEKEND.
A FRONTAL BOUNDARY SHOULD BE SITUATED WEST/EAST NORTH OF OUR
AREA...WITH FLOW OFF THE GULF OF MEXICO BRINGING PLENTIFUL MOISTURE
NORTHWARD INTO OUR AREA. A COMBINATION OF WARM AIR ADVECTION AND
SHORTWAVES ALOFT PASSING THROUGH WILL BRING SHOWERS AND
THUNDERSTORMS AT TIMES TUESDAY THROUGH THURSDAY.
A STRONG LOW PRESSURE SYSTEM WILL DEVELOP OVER THE MIDDLE OF THE
NATION AND TRACK NE OVER THE MIDWEST LATE IN THE WEEK. THIS WILL
PULL THE FRONT NORTHWARD INITIALLY...AND THEN SEND A COLD FRONT
THROUGH OUR LOCAL AREA ON FRIDAY OR FRIDAY EVENING.
THE FRONTAL PASSAGE WILL BRING A RETURN OF DRY WEATHER...BUT MODELS
DO NOT AGREE ON THE EXTENT OF COOLING. HAVE USED A COMPROMISE/BLEND
AT THIS POINT FOR TEMPS. MODELS ALSO SHOW DIFFERENCES IN THE
EVENTUAL HANDLING A SYSTEM WHICH SHOULD MOVE ONSHORE IN SOUTHERN CA
OR NORTHERN MEXICAN BAJA ON SATURDAY. THE ECMWF BRINGS IT EASTWARD
FASTER THAN THE GFS. HAVE ONLY USED LOW POPS TO FINISH THE
WEEKEND...WITH THE SYSTEM POSSIBLY HOLDING OFF UNTIL LATER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 126 AM EDT MON APR 6 2015
VFR CONDITIONS WILL HOLD ON THROUGH THE NIGHT...ALTHOUGH CEILINGS
WILL BE LOWERING WITH TIME. SOME SHOWER ACTIVITY WILL THREATEN
TOWARDS DAWN FROM SOUTHWEST TO NORTHEAST. SHOWERS WILL INCREASE IN
AREAL COVERAGE DURING THE DAY...WITH EVEN A FEW THUNDERSTORMS
POSSIBLE DURING PEAK HEATING. CEILINGS WILL EVENTUALLY LOWER TO
MVFR NEAR AND WEST OF I-75 BY NIGHTFALL...WITH A BIT LESS
UNCERTAINTY TO THE EAST...WHERE LOW END VFR MAY HANG ON. WINDS
WILL RANGE FROM 5 TO 10 KTS THROUGH THE PERIOD...GENERALLY OUT OF
THE SOUTH.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JMW
LONG TERM...HAL
AVIATION...GEOGERIAN/JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
126 AM EDT MON APR 6 2015
.UPDATE...
ISSUED AT 1118 PM EDT SUN APR 5 2015
HIGH CLOUDS HAVE THINNED SOMEWHAT IN THE PAST COUPLE OF HOURS.
THE EASTERN VALLEYS CONTINUE TO DROP OFF...NOW REPORTING IN THE
MID 40S...WHILE RIDGES ARE IN THE UPPER 50S. HAVE INCLUDED MORE
OF A RIDGE/VALLEY SPLIT THROUGH THE NIGHT...UNTIL CLOUDS LOWER AND
THICKEN MORE TOWARDS DAWN. WILL HANG ONTO THE MAINLY SLIGHT CHANCE
POPS IN THE SOUTHWEST TOWARDS DAWN...ALTHOUGH THE LATEST RUNS OF
THE HRRR HAVE TRENDED DRIER. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 757 PM EDT SUN APR 5 2015
THICK HIGH CLOUDS HAVE OVERSPREAD THE AREA THROUGH EARLY THIS
EVENING. LOOKING UPSTREAM...DO NOT SEE MUCH IN THE WAY OF
THINNING...WITH CEILINGS ONLY LOWERING WITH TIME THROUGH THE
NIGHT. THIS WILL AFFECT THE LOW TEMPERATURES...HOWEVER GIVEN THE
STILL VERY DRY LOW LEVEL AIR IN PLACE AND EASTERN VALLEYS ARE
DROPPING A BIT QUICKER THAN FORECAST...WILL STICK WITH THE
FORECAST LOWS FOR NOW. UPDATES WILL BE FORTHCOMING.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 355 PM EDT SUN APR 5 2015
A RELATIVELY ZONAL FLOW PATTERN WAS IN PLACE ACROSS THE CENTRAL
AND EASTERN CONUS WITH A TROUGH OFF THE PACIFIC COAST. WITHIN THIS
FLOW WAS A SHORTWAVE RIDGE THE AXIS OF WHICH IS STARTING TO MOVE
EAST OF THE LOWER OH VALLEY REGION AND EASTERN KY WITH A SHORTWAVE
UPSTREAM MOVING FORM THE PLAINS INTO THE MS VALLEY REGION.
LOCALLY AT PRESENT THE AIR MASS IS VERY DRY WITH DEW POINTS AT
THIS TIME GENERALLY FROM ABOUT 10 IN THE HIGHEST ELEVATIONS OF THE
FAR SOUTHEAST TO THE MID AND UPPER 20S IN THE FAR NW. THIS IS
LEADING TO CURRENT RH IN THE 13 TO 25 PERCENT RANGE FOR THE MOST
PART. MAINLY HIGH CLOUDS AHEAD OF THE NEXT SHORTWAVE CONTINUE TO
ENCROACH...AND A SIGN OF INCREASING MOISTURE ON THE WAY IN THE
WEST SOUTHWEST FLOW ALOFT.
THE SFC HIGH WILL CONTINUE TO SHIFT ON OFF TO THE EAST OF THE AREA
TONIGHT AND INTO MONDAY. SOUTH TO SOUTHWESTERLY FLOW IN THE LOWER
LEVELS WILL INCREASE BETWEEN THIS DEPARTING HIGH AND AN AREA OF
LOW PRESSURE SLOWLY WORKING FROM THE LEE OF THE ROCKIES INTO THE
THE CENTRAL PLAINS. MOISTURE WILL INCREASE IN THIS FLOW RATHER
DRAMATICALLY FROM PRESENT UNTIL LATE TONIGHT. PW IS PROGGED TO
CLIMB FROM AROUND 0.25 TO 0.40 INCHES AT PRESENT TO 0.75 TO 1 INCH
RANGE AROUND DAYBREAK. EASTERN VALLEY LOCATIONS COULD DROP OFF
QUICKLY THIS EVENING DEPENDING ON THICKNESS OF THE CIRRUS AND THE
TIMING OF MID LEVEL DECK ARRIVAL. ATTM...HAVE A FEW POINTS IN THE
BIG SANDY REGION FALLING TO 40 OR THE LOWER 40S.
PW SHOULD THEN FURTHER INCREASE ON MONDAY INTO THE 1 TO 1.25 INCH
RANGE AND THEN REMAIN THERE THROUGH THE END OF THE PERIOD. TOTAL
TOTALS ARE ALSO PROJECTED TO CREEP UP TOWARD 50 BY LATE MONDAY
MORNING INTO MONDAY AFTERNOON...SO SOME THUNDER WILL BE POSSIBLE
ALONG WITH SHOWERS WITH THE ISENTROPIC LIFT MAINLY ON MONDAY
MORNING.
CONFIDENCE IS LOW IN TIMING DETAILS...AREAL EXTENT AND QPF...BUT
WITH A RATHER MOIST AND SOMEWHAT UNSTABLE AIR MASS IN
PLACE...AND CONTINUED ISENTROPIC LIFT...CHANCES FOR SHOWERS AND
POSSIBLY A THUNDERSTORM WILL CONTINUE INTO MONDAY
AFTERNOON...EVENING AND MONDAY NIGHT. THE MODEL GUIDANCE CONSENSUS
AND MOS GUIDANCE POINTS TOWARD A BETTER THAN 50 PERCENT CHANCE FOR
MEASURABLE PRECIPITATION ON MONDAY NIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 426 PM EDT SUN APR 5 2015
THERE IS MODEL AGREEMENT FOR THE FIRST FEW DAYS OF THE PERIOD...BUT
THE ECMWF AND GFS THEN BEGIN TO SHOW MUCH MORE SIGNIFICANT
DIFFERENCES AS TIME PROGRESSES INTO THE WEEKEND.
A FRONTAL BOUNDARY SHOULD BE SITUATED WEST/EAST NORTH OF OUR
AREA...WITH FLOW OFF THE GULF OF MEXICO BRINGING PLENTIFUL MOISTURE
NORTHWARD INTO OUR AREA. A COMBINATION OF WARM AIR ADVECTION AND
SHORTWAVES ALOFT PASSING THROUGH WILL BRING SHOWERS AND
THUNDERSTORMS AT TIMES TUESDAY THROUGH THURSDAY.
A STRONG LOW PRESSURE SYSTEM WILL DEVELOP OVER THE MIDDLE OF THE
NATION AND TRACK NE OVER THE MIDWEST LATE IN THE WEEK. THIS WILL
PULL THE FRONT NORTHWARD INITIALLY...AND THEN SEND A COLD FRONT
THROUGH OUR LOCAL AREA ON FRIDAY OR FRIDAY EVENING.
THE FRONTAL PASSAGE WILL BRING A RETURN OF DRY WEATHER...BUT MODELS
DO NOT AGREE ON THE EXTENT OF COOLING. HAVE USED A COMPROMISE/BLEND
AT THIS POINT FOR TEMPS. MODELS ALSO SHOW DIFFERENCES IN THE
EVENTUAL HANDLING A SYSTEM WHICH SHOULD MOVE ONSHORE IN SOUTHERN CA
OR NORTHERN MEXICAN BAJA ON SATURDAY. THE ECMWF BRINGS IT EASTWARD
FASTER THAN THE GFS. HAVE ONLY USED LOW POPS TO FINISH THE
WEEKEND...WITH THE SYSTEM POSSIBLY HOLDING OFF UNTIL LATER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 126 AM EDT MON APR 6 2015
VFR CONDITIONS WILL HOLD ON THROUGH THE NIGHT...ALTHOUGH CEILINGS
WILL BE LOWERING WITH TIME. SOME SHOWER ACTIVITY WILL THREATEN
TOWARDS DAWN FROM SOUTHWEST TO NORTHEAST. SHOWERS WILL INCREASE IN
AREAL COVERAGE DURING THE DAY...WITH EVEN A FEW THUNDERSTORMS
POSSIBLE DURING PEAK HEATING. CEILINGS WILL EVENTUALLY LOWER TO
MVFR NEAR AND WEST OF I-75 BY NIGHTFALL...WITH A BIT LESS
UNCERTAINTY TO THE EAST...WHERE LOW END VFR MAY HANG ON. WINDS
WILL RANGE FROM 5 TO 10 KTS THROUGH THE PERIOD...GENERALLY OUT OF
THE SOUTH.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JP
LONG TERM...HAL
AVIATION...GEOGERIAN/JMW
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1206 PM CDT MON APR 6 2015
.AVIATION...
THROUGH THE TAF PERIOD ENDING 07/18Z...EXPECTING A GRADUAL IMPROVEMENT
TO VSBYS AND CIGS...FROM WEST TO EAST THIS AFTERNOON...WITH MOST
OF THE FORECAST AREA UNDER VFR BY 07/00Z. ISOLATED CONVECTION
ACROSS NORTHEAST TEXAS INTO SOUTHWEST ARKANSAS AND SOUTHEAST OKLAHOMA
WILL ALSO MOVE EAST OF THE AREA BY 00Z. WITH A FAIRLY STRONG PRESSURE
GRADIENT IN PLACE ACROSS TEXAS...EXPECT SOUTHERLY SURFACE WIND ACROSS
NORTHEAST TEXAS AROUND 15 KTS THIS AFTERNOON WITH GUSTS BTWN 20 AND
25 KTS. THE WIND WILL SUBSIDE SOME AFTER 00Z... REMAINING IN THE
10 TO 15 KT RANGE OVERNIGHT BEFORE INCREASING AGAIN TUESDAY MORNING
AFTER 14Z. THE VFR WEATHER WILL CONTINUE THROUGHOUT THIS EVENING...BUT
AFTER 06Z...EXPECT THE RETURN OF MVFR CIGS... WHICH WILL PERSIST THROUGH
16Z TUESDAY MORNING. /14/
&&
.PREV DISCUSSION... /ISSUED 1123 AM CDT MON APR 6 2015/
DISCUSSION...
SHWRS CONTINUE TO SHIFT EWRD ACROSS THE REGION THIS MORNING IN
RESPONSE TO A WEAK UPPER LEVEL DISTURBANCE TRANSITIONING EAST FROM
TX INTO AR/LA. IN ADDITION...A WARM FRONT HAS SHIFTED NORTH OF THE
REGION LEAVING A VERY MOIST AND NOTICEABLY MUGGY AIR MASS IN
PLACE. ABUNDANT CLOUDS HAVE HELD TEMPERATURES DOWN QUITE A BIT BUT
THERE ARE SIGNS OF CLOUDS BEGINNING TO BREAK OVER PARTS OF E CNTRL
TX. THIS TREND SHOULD CONTINUE INTO THE AFTERNOON FARTHER EAST
ACROSS OUR REGION. SO FOR THIS MORNINGS UPDATE...RAISED POPS INTO
THE LOW CHANCE CATEGORY FOR THE REMAINDER OF THE MORNING AND THEN
DROPPED TO SLIGHT CHANCE FOR THE AFTERNOON WITH ISOLD THUNDER
POSSIBLE IN THIS WARMER AIR MASS. HOWEVER...THE GENERAL TREND WILL
BE FOR DECREASING RAIN CHANCES LATER IN THE DAY AS THE UPPER LEVEL
DISTURBANCE SHIFTS OUT OF OUR REGION. OTHER MINOR ADJUSTMENTS WERE
MADE TO AFTERNOON HIGH TEMPERATURES TO ACCOUNT FOR THE CLOUD COVER
AND SCATTERED CONVECTION. UPDATED PRODUCTS HAVE ALREADY BEEN SENT.
/19/
PREV DISCUSSION... /ISSUED 447 AM CDT MON APR 6 2015/
DISCUSSION...
A CLUSTER OF CONVECTION IS MOVING ACROSS CNTRL TX THIS MORNING IN
ASSOCIATION WITH A WEAK UPPER DISTURBANCE IN THE SWLY FLOW ALOFT.
MOST OF THE MODEL GUIDANCE IS WAY TOO WET...DEPICTING QUITE A BIT
OF QPF ACROSS THE AREA ALREADY THAT IS NOT PRESENT..AND DID NOT
PICK UP ON THE CONVECTIVE CLUSTER OVER CNTRL TX. HRRR SEEMS TO
HAVE THE BEST HANDLE ON THE CURRENT CONDITIONS AND BRINGS THE
WEAKENING CLUSTER INTO OUR NW ZONES...LIKELY ALONG OR JUST SOUTH
OF I-30...TODAY BUT APPEARS TO BE TO FAST. 06Z NAM HAS THE
CLUSTER AND SEEMS TO HANDLE TIMING WELL BUT DISSIPATES THE
CONVECTION REACH OUR AREA. HAVE COMPROMISED BY GOING SLIGHT CHANCE
AREAWIDE THIS MORNING FOR LIGHT RAIN/DRIZZLE AND THEN TRIMMING THE
POPS BACK SLIGHTLY FOR THIS AFTERNOON TO ACCOUNT FOR ANY REMNANTS
OF THE TX CONVECTION. PRECIP SHOULD END BY SUNSET THIS EVENING.
TEMPERATURES TODAY ARE DIFFICULT. ABUNDANT CLOUD COVER MAY REMAIN
IN PLACE FOR MUCH OF THE DAY BEFORE BEGINNING TO BREAK LATE BUT
QUICK WARMING SHOULD OCCUR IF THE CLOUDS TO SCATTER. BEST CHANCES
FOR SOME SUNSHINE SHOULD BE SOUTH OF I-20.
THE LARGE UPPER TROUGH OFF THE PAC NW COAST SHOULD BE MOVING
ACROSS THE CNTRL ROCKIES ON WEDNESDAY. AT THE SFC...A LEE TROUGH
AND COLD FRONT SHOULD ORGANIZE AND MOVE TOWARDS THE AREA. LARGE
SCALE ASCENT FROM THE UPPER TROUGH MAY LEAD TO SOME CONVECTION
ALONG AND NORTH OF I-30 BY LATE WEDNESDAY/EARLY THURSDAY. THE BEST
CHANCES FOR SHWRS/TSTMS WILL BE LATE THURSDAY MORNING THROUGH
EARLY FRIDAY AS THE COLD FRONT MOVES ACROSS THE AREA. BEST
DYNAMICS FOR SEVERE WEATHER SHOULD BE NORTH OF OUR AREA AS THE
UPPER TROUGH AND SFC LOW TRACK ACROSS THE CNTRL PLAINS THROUGH
KS/IA. HOWEVER...INSTABILITY AND DEEP LAYER SHEAR SHOULD STILL BE
SUFFICIENT TO SUPPORT SOME SEVERE TSTMS THURSDAY THROUGH EARLY
FRIDAY. LARGE HAIL AND DAMAGING WINDS APPEAR TO BE THE PRIMARY
THREATS BUT ISOLATED TORNADOES WILL BE POSSIBLE AS WELL.
THE COLD FRONT SHOULD REACH THE GULF COAST BEFORE STALLING BRIEFLY
AND MOVING BACK NWD AS A WARM FRONT ON SATURDAY. THIS WILL KEEP
RAIN IN THE FORECAST PARTICULARLY SOUTH OF I-20. 00Z
GFS/ECMWF...WHILE SHOWING GOOD AGREEMENT ON THIS PARTICULAR
RUN...ARE VERY INCONSISTENT ON A RUN-TO-RUN BASIS REGARDING
ANOTHER STRONG UPPER TROUGH AND COLD FRONT TO IMPACT THE REGION
DURING DAY 7-8 TIME FRAME FOR THE END OF NEXT WEEKEND AND EARLY
NEXT WEEK. WHILE THE DETAILS REMAIN SKETCHY...IT APPEARS MORE
UNSETTLED AND WET WEATHER IS ON THE WAY. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 79 64 83 65 / 30 10 10 10
MLU 78 65 84 65 / 30 10 10 10
DEQ 74 62 78 62 / 30 10 10 10
TXK 76 63 81 63 / 30 10 10 10
ELD 76 63 80 64 / 30 10 10 10
TYR 80 64 82 65 / 30 10 10 10
GGG 79 64 82 65 / 30 10 10 10
LFK 82 65 83 67 / 30 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1123 AM CDT MON APR 6 2015
.DISCUSSION...
SHWRS CONTINUE TO SHIFT EWRD ACROSS THE REGION THIS MORNING IN
RESPONSE TO A WEAK UPPER LEVEL DISTURBANCE TRANSITIONING EAST FROM
TX INTO AR/LA. IN ADDITION...A WARM FRONT HAS SHIFTED NORTH OF THE
REGION LEAVING A VERY MOIST AND NOTICEABLY MUGGY AIR MASS IN
PLACE. ABUNDANT CLOUDS HAVE HELD TEMPERATURES DOWN QUITE A BIT BUT
THERE ARE SIGNS OF CLOUDS BEGINNING TO BREAK OVER PARTS OF E CNTRL
TX. THIS TREND SHOULD CONTINUE INTO THE AFTERNOON FARTHER EAST
ACROSS OUR REGION. SO FOR THIS MORNINGS UPDATE...RAISED POPS INTO
THE LOW CHANCE CATEGORY FOR THE REMAINDER OF THE MORNING AND THEN
DROPPED TO SLIGHT CHANCE FOR THE AFTERNOON WITH ISOLD THUNDER
POSSIBLE IN THIS WARMER AIR MASS. HOWEVER...THE GENERAL TREND WILL
BE FOR DECREASING RAIN CHANCES LATER IN THE DAY AS THE UPPER LEVEL
DISTURBANCE SHIFTS OUT OF OUR REGION. OTHER MINOR ADJUSTMENTS WERE
MADE TO AFTERNOON HIGH TEMPERATURES TO ACCOUNT FOR THE CLOUD COVER
AND SCATTERED CONVECTION. UPDATED PRODUCTS HAVE ALREADY BEEN SENT.
/19/
&&
.PREV DISCUSSION... /ISSUED 515 AM CDT MON APR 6 2015/
AVIATION...
DEALING WITH MOSTLY LIFR CEILINGS AND VSBYS RANGING FROM JUST
BELOW ONE MILE TO MVFR VSBYS EARLY THIS MORNING. SFC WINDS HAVE
VEERED AROUND TO MORE OF A SOUTHERLY DIRECTION THIS MORNING AND
WITH AN INCREASING PRESSURE GRADIENT ACROSS THE SOUTHERN
PLAINS...WINDS HAVE STAYED UP JUST ENOUGH TO KEEP VSBYS FROM
BECOMING TOO RESTRICTED AND TOO WIDESPREAD.
FOR THE MORNING...WILL SHOW A SLOW BUT GRADUAL IMPROVEMENT TO
VSBYS AND CEILINGS WITH SOME PARTIAL SCATTERING OUT OF THE LOW
CLOUD COVER BY AFTN.
GIVEN THE STRENGTHENING PRESSURE GRADIENT IN PLACE ACROSS THE WEST
TODAY...HAVE SHOWN SOME HIGHER GUSTS AT OR NEAR 20KTS OR SO ACROSS
OUR NE TX TERMINAL LOCATIONS.
SHOULD HAVE SCATTERED CLOUD COVER THIS EVENING BUT THIS WILL BE
TEMPORARY AS BOUNDARY LAYER MOISTURE INCREASES ONCE AGAIN AND WITH
THAT WILL BE MVFR/IFR CEILINGS ONCE AGAIN LATE TONIGHT WITH SOME
PATCHY FOG AS WELL.
13
PREV DISCUSSION... /ISSUED 447 AM CDT MON APR 6 2015/
DISCUSSION...
A CLUSTER OF CONVECTION IS MOVING ACROSS CNTRL TX THIS MORNING IN
ASSOCIATION WITH A WEAK UPPER DISTURBANCE IN THE SWLY FLOW ALOFT.
MOST OF THE MODEL GUIDANCE IS WAY TOO WET...DEPICTING QUITE A BIT
OF QPF ACROSS THE AREA ALREADY THAT IS NOT PRESENT..AND DID NOT
PICK UP ON THE CONVECTIVE CLUSTER OVER CNTRL TX. HRRR SEEMS TO
HAVE THE BEST HANDLE ON THE CURRENT CONDITIONS AND BRINGS THE
WEAKENING CLUSTER INTO OUR NW ZONES...LIKELY ALONG OR JUST SOUTH
OF I-30...TODAY BUT APPEARS TO BE TO FAST. 06Z NAM HAS THE
CLUSTER AND SEEMS TO HANDLE TIMING WELL BUT DISSIPATES THE
CONVECTION REACH OUR AREA. HAVE COMPROMISED BY GOING SLIGHT CHANCE
AREAWIDE THIS MORNING FOR LIGHT RAIN/DRIZZLE AND THEN TRIMMING THE
POPS BACK SLIGHTLY FOR THIS AFTERNOON TO ACCOUNT FOR ANY REMNANTS
OF THE TX CONVECTION. PRECIP SHOULD END BY SUNSET THIS EVENING.
TEMPERATURES TODAY ARE DIFFICULT. ABUNDANT CLOUD COVER MAY REMAIN
IN PLACE FOR MUCH OF THE DAY BEFORE BEGINNING TO BREAK LATE BUT
QUICK WARMING SHOULD OCCUR IF THE CLOUDS TO SCATTER. BEST CHANCES
FOR SOME SUNSHINE SHOULD BE SOUTH OF I-20.
THE LARGE UPPER TROUGH OFF THE PAC NW COAST SHOULD BE MOVING
ACROSS THE CNTRL ROCKIES ON WEDNESDAY. AT THE SFC...A LEE TROUGH
AND COLD FRONT SHOULD ORGANIZE AND MOVE TOWARDS THE AREA. LARGE
SCALE ASCENT FROM THE UPPER TROUGH MAY LEAD TO SOME CONVECTION
ALONG AND NORTH OF I-30 BY LATE WEDNESDAY/EARLY THURSDAY. THE BEST
CHANCES FOR SHWRS/TSTMS WILL BE LATE THURSDAY MORNING THROUGH
EARLY FRIDAY AS THE COLD FRONT MOVES ACROSS THE AREA. BEST
DYNAMICS FOR SEVERE WEATHER SHOULD BE NORTH OF OUR AREA AS THE
UPPER TROUGH AND SFC LOW TRACK ACROSS THE CNTRL PLAINS THROUGH
KS/IA. HOWEVER...INSTABILITY AND DEEP LAYER SHEAR SHOULD STILL BE
SUFFICIENT TO SUPPORT SOME SEVERE TSTMS THURSDAY THROUGH EARLY
FRIDAY. LARGE HAIL AND DAMAGING WINDS APPEAR TO BE THE PRIMARY
THREATS BUT ISOLATED TORNADOES WILL BE POSSIBLE AS WELL.
THE COLD FRONT SHOULD REACH THE GULF COAST BEFORE STALLING BRIEFLY
AND MOVING BACK NWD AS A WARM FRONT ON SATURDAY. THIS WILL KEEP
RAIN IN THE FORECAST PARTICULARLY SOUTH OF I-20. 00Z
GFS/ECMWF...WHILE SHOWING GOOD AGREEMENT ON THIS PARTICULAR
RUN...ARE VERY INCONSISTENT ON A RUN-TO-RUN BASIS REGARDING
ANOTHER STRONG UPPER TROUGH AND COLD FRONT TO IMPACT THE REGION
DURING DAY 7-8 TIME FRAME FOR THE END OF NEXT WEEKEND AND EARLY
NEXT WEEK. WHILE THE DETAILS REMAIN SKETCHY...IT APPEARS MORE
UNSETTLED AND WET WEATHER IS ON THE WAY. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 79 64 83 65 / 30 10 10 10
MLU 78 65 84 65 / 30 10 10 10
DEQ 74 62 78 62 / 30 10 10 10
TXK 76 63 81 63 / 30 10 10 10
ELD 76 63 80 64 / 30 10 10 10
TYR 80 64 82 65 / 30 10 10 10
GGG 79 64 82 65 / 30 10 10 10
LFK 82 65 83 67 / 30 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
19
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
515 AM CDT MON APR 6 2015
.AVIATION...
DEALING WITH MOSTLY LIFR CEILINGS AND VSBYS RANGING FROM JUST
BELOW ONE MILE TO MVFR VSBYS EARLY THIS MORNING. SFC WINDS HAVE
VEERED AROUND TO MORE OF A SOUTHERLY DIRECTION THIS MORNING AND
WITH AN INCREASING PRESSURE GRADIENT ACROSS THE SOUTHERN
PLAINS...WINDS HAVE STAYED UP JUST ENOUGH TO KEEP VSBYS FROM
BECOMING TOO RESTRICTED AND TOO WIDESPREAD.
FOR THE MORNING...WILL SHOW A SLOW BUT GRADUAL IMPROVEMENT TO
VSBYS AND CEILINGS WITH SOME PARTIAL SCATTERING OUT OF THE LOW
CLOUD COVER BY AFTN.
GIVEN THE STRENGTHENING PRESSURE GRADIENT IN PLACE ACROSS THE WEST
TODAY...HAVE SHOWN SOME HIGHER GUSTS AT OR NEAR 20KTS OR SO ACROSS
OUR NE TX TERMINAL LOCATIONS.
SHOULD HAVE SCATTERED CLOUD COVER THIS EVENING BUT THIS WILL BE
TEMPORARY AS BOUNDARY LAYER MOISTURE INCREASES ONCE AGAIN AND WITH
THAT WILL BE MVFR/IFR CEILINGS ONCE AGAIN LATE TONIGHT WITH SOME
PATCHY FOG AS WELL.
13
&&
.PREV DISCUSSION... /ISSUED 447 AM CDT MON APR 6 2015/
DISCUSSION...
A CLUSTER OF CONVECTION IS MOVING ACROSS CNTRL TX THIS MORNING IN
ASSOCIATION WITH A WEAK UPPER DISTURBANCE IN THE SWLY FLOW ALOFT.
MOST OF THE MODEL GUIDANCE IS WAY TOO WET...DEPICTING QUITE A BIT
OF QPF ACROSS THE AREA ALREADY THAT IS NOT PRESENT..AND DID NOT
PICK UP ON THE CONVECTIVE CLUSTER OVER CNTRL TX. HRRR SEEMS TO
HAVE THE BEST HANDLE ON THE CURRENT CONDITIONS AND BRINGS THE
WEAKENING CLUSTER INTO OUR NW ZONES...LIKELY ALONG OR JUST SOUTH
OF I-30...TODAY BUT APPEARS TO BE TO FAST. 06Z NAM HAS THE
CLUSTER AND SEEMS TO HANDLE TIMING WELL BUT DISSIPATES THE
CONVECTION REACH OUR AREA. HAVE COMPROMISED BY GOING SLIGHT CHANCE
AREAWIDE THIS MORNING FOR LIGHT RAIN/DRIZZLE AND THEN TRIMMING THE
POPS BACK SLIGHTLY FOR THIS AFTERNOON TO ACCOUNT FOR ANY REMNANTS
OF THE TX CONVECTION. PRECIP SHOULD END BY SUNSET THIS EVENING.
TEMPERATURES TODAY ARE DIFFICULT. ABUNDANT CLOUD COVER MAY REMAIN
IN PLACE FOR MUCH OF THE DAY BEFORE BEGINNING TO BREAK LATE BUT
QUICK WARMING SHOULD OCCUR IF THE CLOUDS TO SCATTER. BEST CHANCES
FOR SOME SUNSHINE SHOULD BE SOUTH OF I-20.
THE LARGE UPPER TROUGH OFF THE PAC NW COAST SHOULD BE MOVING
ACROSS THE CNTRL ROCKIES ON WEDNESDAY. AT THE SFC...A LEE TROUGH
AND COLD FRONT SHOULD ORGANIZE AND MOVE TOWARDS THE AREA. LARGE
SCALE ASCENT FROM THE UPPER TROUGH MAY LEAD TO SOME CONVECTION
ALONG AND NORTH OF I-30 BY LATE WEDNESDAY/EARLY THURSDAY. THE BEST
CHANCES FOR SHWRS/TSTMS WILL BE LATE THURSDAY MORNING THROUGH
EARLY FRIDAY AS THE COLD FRONT MOVES ACROSS THE AREA. BEST
DYNAMICS FOR SEVERE WEATHER SHOULD BE NORTH OF OUR AREA AS THE
UPPER TROUGH AND SFC LOW TRACK ACROSS THE CNTRL PLAINS THROUGH
KS/IA. HOWEVER...INSTABILITY AND DEEP LAYER SHEAR SHOULD STILL BE
SUFFICIENT TO SUPPORT SOME SEVERE TSTMS THURSDAY THROUGH EARLY
FRIDAY. LARGE HAIL AND DAMAGING WINDS APPEAR TO BE THE PRIMARY
THREATS BUT ISOLATED TORNADOES WILL BE POSSIBLE AS WELL.
THE COLD FRONT SHOULD REACH THE GULF COAST BEFORE STALLING BRIEFLY
AND MOVING BACK NWD AS A WARM FRONT ON SATURDAY. THIS WILL KEEP
RAIN IN THE FORECAST PARTICULARLY SOUTH OF I-20. 00Z
GFS/ECMWF...WHILE SHOWING GOOD AGREEMENT ON THIS PARTICULAR
RUN...ARE VERY INCONSISTENT ON A RUN-TO-RUN BASIS REGARDING
ANOTHER STRONG UPPER TROUGH AND COLD FRONT TO IMPACT THE REGION
DURING DAY 7-8 TIME FRAME FOR THE END OF NEXT WEEKEND AND EARLY
NEXT WEEK. WHILE THE DETAILS REMAIN SKETCHY...IT APPEARS MORE
UNSETTLED AND WET WEATHER IS ON THE WAY. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 80 64 83 65 / 20 10 10 10
MLU 79 65 84 65 / 20 10 10 10
DEQ 75 62 78 62 / 20 10 10 10
TXK 77 63 81 63 / 20 10 10 10
ELD 76 63 80 64 / 20 10 10 10
TYR 80 64 82 65 / 20 10 10 10
GGG 79 64 82 65 / 20 10 10 10
LFK 81 65 83 67 / 20 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
09/13
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
447 AM CDT MON APR 6 2015
.DISCUSSION...
A CLUSTER OF CONVECTION IS MOVING ACROSS CNTRL TX THIS MORNING IN
ASSOCIATION WITH A WEAK UPPER DISTURBANCE IN THE SWLY FLOW ALOFT.
MOST OF THE MODEL GUIDANCE IS WAY TOO WET...DEPICTING QUITE A BIT
OF QPF ACROSS THE AREA ALREADY THAT IS NOT PRESENT..AND DID NOT
PICK UP ON THE CONVECTIVE CLUSTER OVER CNTRL TX. HRRR SEEMS TO
HAVE THE BEST HANDLE ON THE CURRENT CONDITIONS AND BRINGS THE
WEAKENING CLUSTER INTO OUR NW ZONES...LIKELY ALONG OR JUST SOUTH
OF I-30...TODAY BUT APPEARS TO BE TO FAST. 06Z NAM HAS THE
CLUSTER AND SEEMS TO HANDLE TIMING WELL BUT DISSIPATES THE
CONVECTION REACH OUR AREA. HAVE COMPROMISED BY GOING SLIGHT CHANCE
AREAWIDE THIS MORNING FOR LIGHT RAIN/DRIZZLE AND THEN TRIMMING THE
POPS BACK SLIGHTLY FOR THIS AFTERNOON TO ACCOUNT FOR ANY REMNANTS
OF THE TX CONVECTION. PRECIP SHOULD END BY SUNSET THIS EVENING.
TEMPERATURES TODAY ARE DIFFICULT. ABUNDANT CLOUD COVER MAY REMAIN
IN PLACE FOR MUCH OF THE DAY BEFORE BEGINNING TO BREAK LATE BUT
QUICK WARMING SHOULD OCCUR IF THE CLOUDS TO SCATTER. BEST CHANCES
FOR SOME SUNSHINE SHOULD BE SOUTH OF I-20.
THE LARGE UPPER TROUGH OFF THE PAC NW COAST SHOULD BE MOVING
ACROSS THE CNTRL ROCKIES ON WEDNESDAY. AT THE SFC...A LEE TROUGH
AND COLD FRONT SHOULD ORGANIZE AND MOVE TOWARDS THE AREA. LARGE
SCALE ASCENT FROM THE UPPER TROUGH MAY LEAD TO SOME CONVECTION
ALONG AND NORTH OF I-30 BY LATE WEDNESDAY/EARLY THURSDAY. THE BEST
CHANCES FOR SHWRS/TSTMS WILL BE LATE THURSDAY MORNING THROUGH
EARLY FRIDAY AS THE COLD FRONT MOVES ACROSS THE AREA. BEST
DYNAMICS FOR SEVERE WEATHER SHOULD BE NORTH OF OUR AREA AS THE
UPPER TROUGH AND SFC LOW TRACK ACROSS THE CNTRL PLAINS THROUGH
KS/IA. HOWEVER...INSTABILITY AND DEEP LAYER SHEAR SHOULD STILL BE
SUFFICIENT TO SUPPORT SOME SEVERE TSTMS THURSDAY THROUGH EARLY
FRIDAY. LARGE HAIL AND DAMAGING WINDS APPEAR TO BE THE PRIMARY
THREATS BUT ISOLATED TORNADOES WILL BE POSSIBLE AS WELL.
THE COLD FRONT SHOULD REACH THE GULF COAST BEFORE STALLING BRIEFLY
AND MOVING BACK NWD AS A WARM FRONT ON SATURDAY. THIS WILL KEEP
RAIN IN THE FORECAST PARTICULARLY SOUTH OF I-20. 00Z
GFS/ECMWF...WHILE SHOWING GOOD AGREEMENT ON THIS PARTICULAR
RUN...ARE VERY INCONSISTENT ON A RUN-TO-RUN BASIS REGARDING
ANOTHER STRONG UPPER TROUGH AND COLD FRONT TO IMPACT THE REGION
DURING DAY 7-8 TIME FRAME FOR THE END OF NEXT WEEKEND AND EARLY
NEXT WEEK. WHILE THE DETAILS REMAIN SKETCHY...IT APPEARS MORE
UNSETTLED AND WET WEATHER IS ON THE WAY. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 80 64 83 65 / 20 10 10 10
MLU 79 65 84 65 / 20 10 10 10
DEQ 75 62 78 62 / 20 10 10 10
TXK 77 63 81 63 / 20 10 10 10
ELD 76 63 80 64 / 20 10 10 10
TYR 80 64 82 65 / 20 10 10 10
GGG 79 64 82 65 / 20 10 10 10
LFK 81 65 83 67 / 20 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
09
AREA FORECAST DISCUSSION...UPDATED
NWS BALTIMORE MD/WASHINGTON DC
1104 PM EDT TUE APR 7 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE SOUTH INTO THE MID-ATLANTIC LATE TONIGHT
NIGHT THROUGH WEDNESDAY. THE BOUNDARY WILL STALL OUT TO OUR SOUTH
THURSDAY BEFORE RETURNING AS A WARM FRONT LATE THURSDAY NIGHT AND
FRIDAY. A COLD FRONT WILL PASS THROUGH FRIDAY NIGHT AND HIGH
PRESSURE WILL RETURN FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
...UPDATE TO START SMALL CRAFT ADVISORY TONIGHT ACROSS ALL OF THE
WATERS. PREVIOUS DISCUSSION FOLLOWS...
A CLUSTER OF SHOWERS EMERGED FM THE APLCNS TAFTN...MADE THE MOST
OF THE LIMITED INSTBY AVBL IN THE ENVIRONMENT...AND CROSSED THE
BLURDG BEFORE DSPTG. WHATS LEFT OF THIS AREA BTWN IAD-DMH ATTM.
ALL DRIVING FEATURES RATHER WEAK AND INNOCUOUS...MAKING IT DFCLT
FOR GDNC TO GET A HANDLE OF WHAT WL BE WHERE WHEN. HRRR DID A
DECENT JOB AT PINPOINTING THE PCPN ERLR THIS EVNG...BUT CARRIED
TOO MUCH OF IT EWD. IT AND THE RAP HV A SIMLR IDEA...BUT QPF
OVERALL STILL GREATER THAN RADAR. NEAREST ORGANIZED PCPN BACK ACRS
THE MID-UPR OHVLY. SO AFTER MAKING AN INITIAL PUSH INCRSG POPS...
HV REVERSED COURSE FOR THE NXT SVRL HRS.
MEANWHILE...A BACKDOOR COLD FRONT WILL PUSH THROUGH THE REGION
FROM NE-SW OVERNIGHT. LTST SFC ANALY HAS IT ACRS SRN PA INTO
CENTRL DEL. /DOV WINDS FM THE EAST./ THIS WILL BACK THE LOW LEVEL
FLOW TO THE ENE BRINGING IN A MUCH COOLER AIRMASS OVERNIGHT. AS
THAT HAPPENS...A STRENGTHENING OVERRUNNING PTTN WL SET UP...WHICH
WL PROVIDE BETTER LIFT FOR PCPN. STILL HV LKLY POPS PREDAWN.
SWITCH PCP CHARACTER FM SHRA TO RA AS WELL AS ADDING AREAS OF FOG.
TEMPS ACRS JERSEY AND PHILLY NWD ALREADY IN THE 40S...SO HV GNLY
HELD ON TO PREV MIN-T FCST W/ A FEW SMALL TWEAKS.
WEDNESDAY WILL BE A COOL AND DREARY DAY AS MUCH OF THE MIDDLE
ATLANTIC WILL BE WEDGED IN A POST FRONTAL ENVIRONMENT. AFTERNOON
HIGH TEMPERATURES WILL REMAIN IN THE 40S OVER THE NORTHERN 1/3RD OF
THE REGION WITH 50S TO NEAR 60 FURTHER SOUTH AND WEST. DRIZZLE...FOG
AND SOME LIGHT RAIN MAY STICK AROUND...ESPECIALLY WITHIN THE I-95
CORRIDOR. HV HIEST POPS DURING THE MRNG HRS AS WAVE EXITS...THEN
DZ SHOULD BECOME MORE PREVALENT.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
A HIGH PRESSURE WEDGE WILL PERSIST ACROSS THE NORTHEASTERN
SEABOARD WEDNESDAY NIGHT AND INTO THURSDAY. LOW PRESSURE IS
EXPECTED TO DEEPEN OFF THE DELMARVA COAST AND A DEEP MARINE LAYER
WILL BE PRESENT ACROSS MUCH OF THE MID-ATLANTIC. MULTIPLE
DISTURBANCES DUE TO CONVECTION WEST OF THE APPALACHIANS WILL LEAD
TO ROUNDS OF RAIN THROUGH THURSDAY. LESS THAN A HALF INCH IS
EXPECTED WEST OF THE BLUE RIDGE. LESSER AMTS EXPECTED ACROSS I-95. A
STRONG INVERSION WILL LEAD TO STABLE CONDITIONS EAST OF THE
APPALACHIANS AND TS IS NOT EXPECTED. LOW LEVEL SATURATION WILL
LEAD TO DRIZZLE AND LOW CLOUDS THROUGH THE PERIOD. BELOW NORMAL
TEMPS WED NIGHT INTO THURSDAY. NE MD WILL ONLY REACH THE UPPER 40S
THURSDAY. FURTHER SW TEMPS WILL BE WARMER...AROUND 50 IN NOVA AND
DC AND 65 IN THE SHENANDOAH VALLEY WHICH IS THE FURTHEST AWAY FROM
THE MARINE SOURCE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A STALLED FRONT WILL LIFT NORTH AS A WARM FRONT LATE THURSDAY NIGHT
INTO FRIDAY AS LOW PRESSURE MOVES NORTHEASTWARD ACROSS THE GREAT
LAKES. A COUPLE OF RAIN SHOWERS AND PERHAPS PERHAPS PATCHY DRIZZLE
WILL EVOLVE AS MILDER AIR OVERRUNS COOLER AIR. TEMPERATURES WILL
RANGE FROM THE MIDDLE 50S SOUTHWEST TO MIDDLE 40S NORTHEAST. THIS IS
5 TO 10 DEGREES ABOVE NORMAL.
BY MIDDAY FRIDAY AND FRIDAY AFTERNOON...AN INCREASING SOUTH TO
SOUTHWEST WIND LEADING TO WARM AIR ADVECTION WILL BRING OUR
TEMPERATURES QUICKLY UP THROUGH THE 50S AND 60S...REACHING THE
70S BY MIDDAY. BY MID AFTERNOON...A FEW PLACES COULD ENCOUNTER
TEMPERATURES REACHING THE 80S. ANY BREAKS IN THE CLOUD COVER WILL
LEAD TO GREATER INSTABILITY AND HEAVIER SHOWERS. A FEW
THUNDERSTORMS THAT DEVELOP DURING THE AFTERNOON AND EVENING COULD
BE STRONG. A COLD FRONT IS EXPECTED TO PUSH ACROSS THE REGION AT
SOME POINT FRIDAY AFTERNOON AND EVENING.
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE MIDWEST
SATURDAY...BUILD OVERHEAD THE METROPOLITAN AREA SUNDAY...BEFORE
PIVOTING OFFSHORE SOUTHERN NEW ENGLAND MONDAY. ALTHOUGH THERE IS A
CHANCE FOR SOME LIGHT RAIN SHOWERS ALONG A WEAK WARM FRONT LATE
SUNDAY INTO EARLY MONDAY...HIGH PRESSURE WILL STILL REMAIN IN
CONTROL ACROSS MUCH OF THE REGION. ANY RAIN SHOWERS THAT WOULD
DEVELOP WOULD BE MORE PROMINANT IN THE CENTRAL POTOMAC HIGHLANDS.
TEMPERATURES SATURDAY WILL ONLY REACH THE MIDDLE 60S. SUNDAY`S HIGHS
WILL ALSO BE IN THE 60S ACROSS MUCH OF THE REGION. TEMPERATURES
MONDAY COULD TOP THE 70 DEGREE MARK WHEN HIGH PRESSURE MOVES EAST
THEN NORTH.
THERE IS A SLIGHT CHANCE OF RAIN SHOWERS MONDAY WITH A SLIGHT
INCREASE IN HUMIDITY. HOWEVER...AN APPROACHING COLD FRONT LATE
TUESDAY AND TUESDAY NIGHT WILL BRING BETTER CHANCES OF SHOWERS AND
PERHAPS A THUNDERSTORM.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
VFR STILL PREVAILS ACRS THE TERMINALS...BUT THAT WONT LAST FOR
MUCH LONGER. HV CIGS DROPPING QUICKER THAN VSBYS AS A MARITIME AMS
SWEEPS ACRS THE TERMINALS BHD A BACKDOOR CDFNT. WL BE IFR BEFORE
MRNG PUSH. ALSO SHUD HV A WIND SHIFT TO THE EAST WITH ACCOMPANYING
GUSTS UP TO 20 KT DCA/BWI/MTN.
IFR CIGS AND MVFR-OCNL IFR VSBYS WL CONT WEDNESDAY. HIGH
CONFIDENCE IN FLGT RESTRICTIONS. ONLY QSTN WL BE WHETHER
PREVAILING WL BE IFR...BRIEFLY UP TO MVFR...OR DOWN TO LIFR. ELY
FLOW WL CONT AS WELL...W/ HIER GUSTS ALONG THE I-95 METRO
TERMINALS.
MVFR/IFR CONDITIONS LIKELY WED NIGHT THROUGH THURSDAY NIGHT AS
MARINE AIR MASS STAYS IN PLACE. SUB-VFR CONDITIONS ARE POSSIBLE
FRIDAY AS SHOWERS AND THUNDERSTORMS IMPACT THE TERMINALS.
&&
.MARINE...
BACKDOOR COLD FRONT N OF POOLES ISLAND ATTM...AND WILL PUSH
THROUGH THE WATERS TONIGHT. WINDS WILL BACK AROUND TO THE ENE AND
INCREASE TO SCA LEVELS OVERNIGHT INTO WEDNESDAY. HV ADDED REST OF
WATERS TO SCA WHICH IS IN EFFECT THROUGH WED. VSBY RESTRICTIONS
MAY BECOME MORE PRONOUNCED BY WED AFTN IN DZ AND FOG.
EASTERLY WINDS WILL PERSIST WED NIGHT THROUGH THURSDAY. SMALL CRAFT
ADVISORY CONDITIONS POSSIBLE FRIDAY...MAINLY OVER THE MAIN STEM
CHESAPEAKE BAY...FOR THE TIME BEING. SOUTHERLY WINDS WILL GUST 15
TO 20 KNOTS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT WEDNESDAY FOR ANZ530>533-
535-538>541.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT WEDNESDAY FOR ANZ534-536-
537-542-543.
&&
$$
SYNOPSIS...HAS
NEAR TERM...HTS/KRW
SHORT TERM...HAS
LONG TERM...KLW
AVIATION...HAS/HTS/KLW/KRW
MARINE...HAS/HTS/KLW/KRW
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
835 PM EDT TUE APR 7 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE SOUTH INTO THE MID-ATLANTIC LATE TONIGHT
NIGHT THROUGH WEDNESDAY. THE BOUNDARY WILL STALL OUT TO OUR SOUTH
THURSDAY BEFORE RETURNING AS A WARM FRONT LATE THURSDAY NIGHT AND
FRIDAY. A COLD FRONT WILL PASS THROUGH FRIDAY NIGHT AND HIGH
PRESSURE WILL RETURN FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
A CLUSTER OF SHOWERS EMERGED FM THE APLCNS TAFTN...MADE THE MOST
OF THE LIMITED INSTBY AVBL IN THE ENVIRONMENT...AND CROSSED THE
BLURDG BEFORE DSPTG. WHATS LEFT OF THIS AREA BTWN IAD-DMH ATTM.
ALL DRIVING FEATURES RATHER WEAK AND INNOCUOUS...MAKING IT DFCLT
FOR GDNC TO GET A HANDLE OF WHAT WL BE WHERE WHEN. HRRR DID A
DECENT JOB AT PINPOINTING THE PCPN ERLR THIS EVNG...BUT CARRIED
TOO MUCH OF IT EWD. IT AND THE RAP HV A SIMLR IDEA...BUT QPF
OVERALL STILL GREATER THAN RADAR. NEAREST ORGANIZED PCPN BACK ACRS
THE MID-UPR OHVLY. SO AFTER MAKING AN INITIAL PUSH INCRSG POPS...
HV REVERSED COURSE FOR THE NXT SVRL HRS.
MEANWHILE...A BACKDOOR COLD FRONT WILL PUSH THROUGH THE REGION
FROM NE-SW OVERNIGHT. LTST SFC ANALY HAS IT ACRS SRN PA INTO
CENTRL DEL. /DOV WINDS FM THE EAST./ THIS WILL BACK THE LOW LEVEL
FLOW TO THE ENE BRINGING IN A MUCH COOLER AIRMASS OVERNIGHT. AS
THAT HAPPENS...A STRENGTHENING OVERRUNNING PTTN WL SET UP...WHICH
WL PROVIDE BETTER LIFT FOR PCPN. STILL HV LKLY POPS PREDAWN.
SWITCH PCP CHARACTER FM SHRA TO RA AS WELL AS ADDING AREAS OF FOG.
TEMPS ACRS JERSEY AND PHILLY NWD ALREADY IN THE 40S...SO HV GNLY
HELD ON TO PREV MIN-T FCST W/ A FEW SMALL TWEAKS.
WEDNESDAY WILL BE A COOL AND DREARY DAY AS MUCH OF THE MIDDLE
ATLANTIC WILL BE WEDGED IN A POST FRONTAL ENVIRONMENT. AFTERNOON
HIGH TEMPERATURES WILL REMAIN IN THE 40S OVER THE NORTHERN 1/3RD OF
THE REGION WITH 50S TO NEAR 60 FURTHER SOUTH AND WEST. DRIZZLE...FOG
AND SOME LIGHT RAIN MAY STICK AROUND...ESPECIALLY WITHIN THE I-95
CORRIDOR. HV HIEST POPS DURING THE MRNG HRS AS WAVE EXITS...THEN
DZ SHOULD BECOME MORE PREVALENT.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
A HIGH PRESSURE WEDGE WILL PERSIST ACROSS THE NORTHEASTERN
SEABOARD WEDNESDAY NIGHT AND INTO THURSDAY. LOW PRESSURE IS
EXPECTED TO DEEPEN OFF THE DELMARVA COAST AND A DEEP MARINE LAYER
WILL BE PRESENT ACROSS MUCH OF THE MID-ATLANTIC. MULTIPLE
DISTURBANCES DUE TO CONVECTION WEST OF THE APPALACHIANS WILL LEAD
TO ROUNDS OF RAIN THROUGH THURSDAY. LESS THAN A HALF INCH IS
EXPECTED WEST OF THE BLUE RIDGE. LESSER AMTS EXPECTED ACROSS I-95. A
STRONG INVERSION WILL LEAD TO STABLE CONDITIONS EAST OF THE
APPALACHIANS AND TS IS NOT EXPECTED. LOW LEVEL SATURATION WILL
LEAD TO DRIZZLE AND LOW CLOUDS THROUGH THE PERIOD. BELOW NORMAL
TEMPS WED NIGHT INTO THURSDAY. NE MD WILL ONLY REACH THE UPPER 40S
THURSDAY. FURTHER SW TEMPS WILL BE WARMER...AROUND 50 IN NOVA AND
DC AND 65 IN THE SHENANDOAH VALLEY WHICH IS THE FURTHEST AWAY FROM
THE MARINE SOURCE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A STALLED FRONT WILL LIFT NORTH AS A WARM FRONT LATE THURSDAY NIGHT
INTO FRIDAY AS LOW PRESSURE MOVES NORTHEASTWARD ACROSS THE GREAT
LAKES. A COUPLE OF RAIN SHOWERS AND PERHAPS PERHAPS PATCHY DRIZZLE
WILL EVOLVE AS MILDER AIR OVERRUNS COOLER AIR. TEMPERATURES WILL
RANGE FROM THE MIDDLE 50S SOUTHWEST TO MIDDLE 40S NORTHEAST. THIS IS
5 TO 10 DEGREES ABOVE NORMAL.
BY MIDDAY FRIDAY AND FRIDAY AFTERNOON...AN INCREASING SOUTH TO
SOUTHWEST WIND LEADING TO WARM AIR ADVECTION WILL BRING OUR
TEMPERATURES QUICKLY UP THROUGH THE 50S AND 60S...REACHING THE
70S BY MIDDAY. BY MID AFTERNOON...A FEW PLACES COULD ENCOUNTER
TEMPERATURES REACHING THE 80S. ANY BREAKS IN THE CLOUD COVER WILL
LEAD TO GREATER INSTABILITY AND HEAVIER SHOWERS. A FEW
THUNDERSTORMS THAT DEVELOP DURING THE AFTERNOON AND EVENING COULD
BE STRONG. A COLD FRONT IS EXPECTED TO PUSH ACROSS THE REGION AT
SOME POINT FRIDAY AFTERNOON AND EVENING.
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE MIDWEST
SATURDAY...BUILD OVERHEAD THE METROPOLITAN AREA SUNDAY...BEFORE
PIVOTING OFFSHORE SOUTHERN NEW ENGLAND MONDAY. ALTHOUGH THERE IS A
CHANCE FOR SOME LIGHT RAIN SHOWERS ALONG A WEAK WARM FRONT LATE
SUNDAY INTO EARLY MONDAY...HIGH PRESSURE WILL STILL REMAIN IN
CONTROL ACROSS MUCH OF THE REGION. ANY RAIN SHOWERS THAT WOULD
DEVELOP WOULD BE MORE PROMINANT IN THE CENTRAL POTOMAC HIGHLANDS.
TEMPERATURES SATURDAY WILL ONLY REACH THE MIDDLE 60S. SUNDAY`S HIGHS
WILL ALSO BE IN THE 60S ACROSS MUCH OF THE REGION. TEMPERATURES
MONDAY COULD TOP THE 70 DEGREE MARK WHEN HIGH PRESSURE MOVES EAST
THEN NORTH.
THERE IS A SLIGHT CHANCE OF RAIN SHOWERS MONDAY WITH A SLIGHT
INCREASE IN HUMIDITY. HOWEVER...AN APPROACHING COLD FRONT LATE
TUESDAY AND TUESDAY NIGHT WILL BRING BETTER CHANCES OF SHOWERS AND
PERHAPS A THUNDERSTORM.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
VFR STILL PREVAILS ACRS THE TERMINALS...BUT THAT WONT LAST FOR
MUCH LONGER. HV CIGS DROPPING QUICKER THAN VSBYS AS A MARITIME AMS
SWEEPS ACRS THE TERMINALS BHD A BACKDOOR CDFNT. WL BE IFR BEFORE
MRNG PUSH. ALSO SHUD HV A WIND SHIFT TO THE EAST WITH ACCOMPANYING
GUSTS UP TO 20 KT DCA/BWI/MTN.
IFR CIGS AND MVFR-OCNL IFR VSBYS WL CONT WEDNESDAY. HIGH
CONFIDENCE IN FLGT RESTRICTIONS. ONLY QSTN WL BE WHETHER
PREVAILING WL BE IFR...BRIEFLY UP TO MVFR...OR DOWN TO LIFR. ELY
FLOW WL CONT AS WELL...W/ HIER GUSTS ALONG THE I-95 METRO
TERMINALS.
MVFR/IFR CONDITIONS LIKELY WED NIGHT THROUGH THURSDAY NIGHT AS
MARINE AIR MASS STAYS IN PLACE. SUB-VFR CONDITIONS ARE POSSIBLE
FRIDAY AS SHOWERS AND THUNDERSTORMS IMPACT THE TERMINALS.
&&
.MARINE...
BACKDOOR COLD FRONT N OF POOLES ISLAND ATTM...AND WILL PUSH
THROUGH THE WATERS TONIGHT. WINDS WILL BACK AROUND TO THE ENE AND
INCREASE TO SCA LEVELS OVERNIGHT INTO WEDNESDAY. HV ADDED REST OF
WATERS TO SCA IN STAGES-- MOST OF BAY /N OF DRUM PT/ AND UPR TIDAL
PTMC OVNGT AND THEN ALL WATERS WED. VSBY RESTRICTIONS MAY BECOME
MORE PRONOUNCED BY WED AFTN IN DZ AND FOG.
EASTERLY WINDS WILL PERSIST WED NIGHT THROUGH THURSDAY. SMALL CRAFT
ADVISORY CONDITIONS POSSIBLE FRIDAY...MAINLY OVER THE MAIN STEM
CHESAPEAKE BAY...FOR THE TIME BEING. SOUTHERLY WINDS WILL GUST 15
TO 20 KNOTS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EDT
WEDNESDAY FOR ANZ530>533-535-538>541.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT WEDNESDAY FOR
ANZ534-536-537-542-543.
&&
$$
SYNOPSIS...HAS
NEAR TERM...HTS/KRW
SHORT TERM...HAS
LONG TERM...KLW
AVIATION...HTS/HAS/KLW
MARINE...HTS/HAS/KLW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
734 PM EDT TUE APR 7 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 448 PM EDT TUE APR 7 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE CONFLUENT FLOW
THAT HAS BEEN ACROSS THE UPPER GREAT LAKES IS SHIFTING E AND NE AS
THE NRN STREAM TROF OVER ERN CANADA IS SLOWLY LIFTING OUT AND SRN
BRANCH RIDGE OVER THE PLAINS DOWNSTREAM OF TROF ALONG THE W COAST IS
GRADUALLY BUILDING NE AND E. SFC HIGH PRES SUPPORTED BY THE
CONFLUENT FLOW ALOFT RIDGES W-E ACROSS NRN ONTARIO INTO SRN QUEBEC.
ALTHOUGH THERE HAVE BEEN SOME MID-LEVEL RADAR RETURNS ACROSS THE
FCST AREA...ESPECIALLY EARLIER TODAY...THE VERY DRY AIR AT THE LOWER
LEVELS EMANATING FROM THE HIGH PRES RIDGE HAS RESULTED IN DRY
WEATHER ACROSS THE FCST AREA TODAY. IN FACT...THE KEWEENAW AND ERN
UPPER MI HAVE ENJOYED MOSTLY SUNNY SKIES FOR A GOOD PART OF THE DAY.
TO THE S...WARM FRONT/STATIONARY FRONT EXTENDS FROM KS ACROSS CNTRL
IL INTO NRN OHIO. TO THE W AND SW...A WELL-DEFINED SHORTWAVE IS
TRACKING ENE ACROSS SE SASKATCHEWAN WHILE WEAKER WAVES ARE MOVING
ACROSS WY/CO AND OUT ACROSS THE PLAINS. THESE FEATURES WILL PLAY A
ROLE IN A CHALLENGING FCST HERE TONIGHT/WED.
INITIALLY...EXPECT DRY WEATHER TO PREVAIL THIS EVENING UNDER A
CONTINUED FEED OF DRY LOW-LEVEL AIR FROM THE E AND NE. SFC DWPTS AS
OF 19Z WERE STILL MOSTLY IN THE 5-10F RANGE ALONG THE MI/WI
BORDER...INDICATING THE DRYNESS THAT IS STILL AT THE SFC...AND
LATEST RAP FCST SOUNDINGS SHOW THE DRY AIR IN THE LOWER LEVELS
HANGING ON DURING THE EVENING. LATER TONIGHT INTO WED...FOCUS SHIFTS
TO THE AFORMENTIONED SHORTWAVES. THE STRONGER NRN WAVE WILL REACH
NRN ONTARIO EARLY WED MORNING WHILE THE WEAKER SRN WAVES WILL TRACK
INTO THE UPPER LAKES. TRACK OF THE STRONGER NRN WAVE INDICATES ITS
MAIN FORCING WILL PASS N OF HERE...AND THAT IS WHAT MODELS SHOW FOR
PROGRESSION OF DEEP LAYER QVECTORS. FARTHER S...THE WEAKER SRN WAVES
WILL BE ABLE TO INTERACT WITH THE SFC-850MB WARM FRONT AND
CONSIDERABLY MORE GENEROUS MOISTURE AS WELL AS ABUNDANT INSTABILITY.
LEAD SUBTLE WAVE IS ALREADY GENERATING AN EXPANDING AREA OF
SHRA/TSRA IN SRN MN/NW IA ON THE MUCAPE GRADIENT PER LATEST SPC
MESOANALYSIS. THRU WED MORNING...MODELS SHOW 850MB WARM FRONT NEVER
LIFTING ANY FARTHER N THAN SRN WI. BELIEVE THOSE MODEL SOLUTIONS
WHICH SHOW THE MAIN AREA OF PCPN PASSING S OF UPPER MI TONIGHT/WED
MORNING CLOSER TO 850MB WARM FRONT OR EVEN SFC FRONT ARE PROBABLY ON
THE RIGHT TRACK. THIS WOULD BE ESPECIALLY TRUE IF SIGNIFICANT
CONVECTION ENDS UP DEVELOPING/EXPANDING NEAR THE WARM FRONT...A
DEFINITE POSSIBILITY GIVEN THE MAGNITUDE OF INSTABILITY THAT WILL
REMAIN MUCH FARTHER S. WHILE THE SHRA/TSRA MOVING ACROSS SRN MN INTO
SW WI IS A CONCERN...THAT PCPN SHOULD TEND TO PEEL MORE EASTWARD
WITH TIME AS THE SHRA/TSRA SHOULDN`T BREAK TOO FAR AWAY FROM THE
INSTABILITY GRADIENT WHICH WILL REMAIN WELL S OF HERE. SO...THE GFS
WHICH CARRIES 1/3RD TO 1/2 INCH OF PCPN INTO SCNTRL UPPER MI
CERTAINLY LOOKS LIKE AN OUTLIER COMPARED TO THE OTHER MODELS WHICH
ARE MUCH LIGHTER ON PCPN. NONETHELESS...TAIL END OF NRN SHORTWAVE
WILL PROVIDE SUPPORT FOR AN EXTENSION OF PCPN N AND NW FROM HEAVIER
PCPN TO THE S. UTILIZING A CONSENSUS APPROACH FOR POPS...WEIGHTED
TOWARD HIGH RES GUIDANCE...WILL SPREAD A BAND OF CHC POPS ACROSS THE
AREA OVERNIGHT/WED MORNING WITH TREND TOWARD LOWER POPS OVER THE
NRN/ERN FCST AREA. WILL INCLUDE LIKELY POPS INTO MENOMINEE COUNTY.
PCPN WILL END (OR DIMINISH TO DZ BEFORE ENDING) FROM SW TO NE MID
MORNING THRU EARLY AFTN.
PTYPE IS A CHALLENGE. INITIAL DRY AIR MASS/EVAPORATIVE COOLING
SHOULD MAKE SNOW THE MORE DOMINANT PTYPE. HOWEVER...PERUSAL OF MODEL
FCST SOUNDINGS SHOW TEMP PROFILE HOVERING AROUND 0C OVER A FAIRLY
SIGNIFICANT DEPTH...INDICATING A VARIETY OF PTYPES WILL BE POSSIBLE
WITH ONLY VERY SLIGHT CHANGES TO THE TEMP PROFILE. SO...FCST WILL
REFLECT A WINTRY MIX OF SN/IP/FZRA/RA AT MOST LOCATIONS...THOUGH
MAINLY SN IS MORE LIKELY IN HIGHER TERRAIN AREAS. FOR PCPN
AMOUNTS...EXPECT TOTAL WATER EQUIVALENT PCPN OF ROUGHLY 0.05 TO 0.15
INCHES....GREATEST SCNTRL. SNOW AMOUNTS SHOULD BE UNDER 1 INCH...AND
WHERE FRZA OCCURS...A COUPLE OF HUNDREDTHS ARE POSSIBLE. AT THIS
POINT...ADVY HEADLINES ARE NOT WARRANTED. IF FOR SOME REASON TRENDS
THIS EVENING POINT TOWARD HEAVIER PCPN REACHING THE AREA...HEADLINES
WILL NEED TO BE RECONSIDERED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 414 PM EDT TUE APR 7 2015
...AREAS OF FREEZING RAIN/ICING WED NIGHT INTO THU MORNING AND
POSSIBLE HEAVY SNOW THU NIGHT...
LARGE SCALE UPPER LEVEL PATTERN TO START THE LONG TERM FEATURES
TROUGHING FM CENTRAL CANADA SOUTHWEST ACROSS MUCH OF THE WESTERN
CONUS. MAIN SHORTWAVES WITHIN THE TROUGH ON WEDNESDAY NIGHT WILL BE
DIVING SOUTHEAST ACROSS MANITOBA AND STREAMING EASTWARD NEAR THE
FOUR CORNERS REGION. MAIN JET STREAKS WITHIN THE FLOW PATTERN ARE
ORIENTED FM GREAT LAKES TO NEW ENGLAND AND PUSHING ACROSS NORTHERN
MEXICO. AT THE SFC...MAIN CYCLONE IS VCNTY OF CNTRL PLAINS WITH WARM
FRONT EAST ACROSS THE OHIO VALLEY...LIFTING NORTHWARD.
WEAKER LEAD SHORTWAVE/INCREASING DIVERGENCE IN RRQ OF GREAT LAKES
JET/WARM AIR ADVECTION COMBINE TO BRING SOME PRECIP IN THE FORM OF
RAIN SHOWERS OVER THE REGION WEDNESDAY NIGHT INTO THURSDAY MORNING.
GFS/ECMWF/GEM-NH QUICKER IN BRINGING PRECIP OVER AREA...MORE 06Z-12Z
THURSDAY. NAM IS DELAYED...FAVORING 12Z-18Z ON THURSDAY. EITHER WAY
THINK BEST FOCUS FOR RAIN WILL BE ON NOSE OF VEERING H85 JET MAINLY
IMPACTING SOUTH AND EAST CWA. TSRA THAT COULD BE ONGOING ALONG WARM
FRONT COULD FURTHER DISRUPT MOISTURE TRANSPORT INTO UPPER GREAT
LAKES. DUE TO THESE REASONS...LIKE THE IDEA OF LESS QPF SINCE LARGER
SCALE FORCING OVER UPR MICHIGAN IS GENERALLY WEAK. SOUNDINGS AHEAD
OF ANY POTENTIAL PRECIP INDICATE LOW-LEVEL MOISTURE TO H9 BUT DRY
AIR ABOVE THROUGH H5 MUCH OF WEDNESDAY EVENING. SFC WINDS FM EAST
BTWN HIGH PRESSURE RIDGE OVER EASTERN CANADA AND LOW PRESSURE
LIFTING NORTHEAST OVER THE CNTRL PLAINS SUPPORTS BEST CHANCE OF
DZ/FZDZ GENERATED BY UPSLOPE LIFTING OVER HIGHER TERRAIN OF CNTRL
CWA FM MICHIGAMME HIGHLANDS IN BARAGA AND MARQUETTE COUNTY SOUTHWEST
TO MUCH OF IRON AND DICKINSON COUNTIES. EITHER FM THE FZDZ OR
EVENTUALLY ARRIVAL OF LIGHT FZRA...LIGHT ICING IS LIKELY ON
WEDNESDAY NIGHT AS TEMPS WILL STAY AT OR BLO FREEZING MOST OF THE
NIGHT. MAIN CONCERN WOULD BE ON UNTREATED ROADS AND SIDEWALKS BUT
THERE COULD ALSO BE SOME ICING THAT WOULD IMPACT ELEVATED OBJECTS
SUCH AS TREES AND POWERLINES. BEST SHOT OF MOST ICING WILL BE OVER
THE HIGHER TERRAIN AREAS FM BARAGA AND MARQUETTE COUNTY TO IRON AND
DICKINSON COUNTY. DID NOT GET TOO SPECIFIC BTWN DZ/FZDZ AND
RAIN/FZRA. SINCE EVEN IN THE DRIER SCENARIO THERE WOULD BE
MEASURABLE QPF...WENT WITH RAIN/FZRA. WILL KEEP MENTION OF THIS IN
HWO/EHWO...BUT NO HEADLINE ISSUED NOW AS AT THIS POINT SEEMS THAT AT
WORST COULD NEED AN ADVY.
BRIEF LULL POSSIBLE LATER THURSDAY MORNING INTO THURSDAY AFTERNOON
IN BETWEEN SHORTWAVES...LEAD ONE LIFTING ACROSS EASTERN ONTARIO AND
A MUCH STRONGER ONE...EDGING EASTWARD ACROSS CNTRL PLAINS...SET TO
ARRIVE OVER UPR GREAT LAKES THURSDAY NIGHT. SOUNDINGS FOR LATER
THURSDAY INDICATE SOME MOISTURE MAY STICK AROUND ON NORTHERN EDGE OF
SFC LOW LIFTING NORTHEAST FROM THE CNTRL MISSISSIPPI RIVER VALLEY
TOWARD THE WESTERN GREAT LAKES...BUT SEEMS THAT NET FORCING FOR
ANY PRECIP WILL BE MINIMAL. NORTHERN EDGE OF HIGHER MLCAPE AND
INTERSECTION OF LOW-LEVEL AND UPPER LEVEL JET AND H85 THETA-E
AXIS/MAX WARM AIR ADVECTION WOULD KEEP POTENTIAL FOR TSRA STAYING
WELL TO THE SOUTHEAST OF UPR MICHIGAN...LIKELY OVER LOWER GREAT
LAKES OR OHIO VALLEY DEPENDING ON LOCATION OF EMBEDDED WEAKER
CONVECTIVELY DRIVEN SHORTWAVES IN THE WSW FLOW ALOFT. GENERALLY
QUIET WEATHER SHOULD PREVAIL OVER UPPER LAKES THURSDAY AFTN UNTIL
MAIN SHORTWAVE ARRIVES ON THURSDAY NIGHT. MOISTURE ADVECTION INTO
THE AREA MAY CONTINUE TO SPUR ON SOME SHOWERS OR PATCHY RAIN...SO
KEPT CHANCES GOING THROUGH THE PERIOD DESPITE THE MINIMAL FORCING.
MODEL DIFFERENCES WITH STRENGTH AND WESTWARD EXTENT OF THURSDAY
NIGHT SHORTWAVE IS THE MAIN ISSUE ON INTO FRIDAY MORNING. OVERALL...
RECENT NAM/GEM-NH RUNS WERE FARTHER WEST WITH UPPER WAVE AND SFC
LOW WHILE THE 00Z ECMWF WAS MUCH FASTER WITH EASTWARD PUSH OF THE
SHORTWAVE/SFC LOW AND COLD FRONT. GFS REPRESENTED A COMPROMISE
SOLUTION. BY FAR...00Z AND 12Z ECMWF ARE DRIEST...INDICATING LESS
THAN 0.25 INCH OF QPF FM 00Z FRIDAY TO 12Z FRIDAY. MEANWHILE...
NAM/GFS/GEM-NH SHOWED QPF AMOUNTS AT LEAST UP TO 1 INCH...SO QUITE
THE DIFFERENCE.
12Z NAM TRENDED MORE LIKE THE GFS IN TERMS OF LOCATION OF SFC LOW FM
00Z FRIDAY TO 12Z FRIDAY. IN TERMS OF QPF...NAM TRENDED AWAY FM
STRIPE OF 1.5 INCH PLUS AMOUNTS IT WAS SHOWING BUT STILL HAS UP TO
1.25 INCHES OVER PARTS OF WESTERN UPR MICHIGAN. IN FACT...IN THE
VCNTY OF KIWD IS HAS TRENDED MUCH WETTER AS 00Z RUN SHOWED LESS THAN
0.10 INCH...BUT 12Z RUN NOW HAS ALMOST 0.75 INCHES. GUESSING THIS IS
DUE TO MORE PHASING OCCURRING BTWN SHORTWAVE CROSSING THE UPPER
LAKES AND THE APPROACHING WAVE DRIVING SOUTHEAST OVER MANITOBA AND
NORTHERN ONTARIO WHICH IN TURN INCREASES RIGHT ENTRANCE JET STREAK
DIVERGENCE AND ASSOCIATED MID-LEVEL FGEN. 12Z GFS SIMILAR TO
PREVIOUS RUNS WITH SFC LOW POSITION...BUT NOW FOCUSES QPF MORE OVER
WESTERN CWA. GFS SHOWS NOT ONLY MAIN SHORTWAVE LIFTING OVER UPPER
GREAT LAKES AND WAVE OVER NORTHERN ONTARIO...BUT ALSO ANOTHER WAVE
TRYING TO SNEAK IN FM NORTHERN PLAINS. SCENARIO JUST BECOMES MORE
COMPLICATED YET. PTYPE WITH MOST OF THE PRECIP WOULD BE RAIN
CHANGING TO SNOW. POSSIBLE FZRA AS WELL AS ADVECTION OF COLDER LOW-
LEVEL AIRMASS UNDERCUTS LINGERING WARM LAYER ALOFT AT H8-H75. SIGNAL
FOCUSING THAT FAR WEST VCNTY OF KIWD COULD SEE HEAVY SNOW THURSDAY
EVENING INTO THE EARLY MORNING OF FRIDAY DUE TO QUICKER CHANGE FM
RAIN TO SNOW AND GREATER POTENTIAL FOR HEAVIER QPF. WILL CONTINUE TO
MENTION THIS IN THE HWO/EHWO BUT NOT HIT IT UP MUCH HARDER JUST YET
AS UNCERTAINTY REMAINS SINCE THE TYPICALLY BETTER PERFORMING ECMWF
HAS BEEN CONSISTENTLY NOT NEAR AS BULLISH WITH THE SYSTEM AS OTHER
MODELS. AND ITS REALLY NOT EVEN CLOSE.
LOW PRESSURE SYSTEM EXITS ACROSS EASTERN CANADA ON FRIDAY. LINGERING
AIRMASS IS COOL THOUGH AS LOWERED TEMPS WITH THERMAL TROUGH AT H85
REMAINING OVER THE AREA. SHOULD STAY MOSTLY CLOUDY EVEN FARTHER
INLAND WITH POSSIBLE INSTABILITY RAIN/SNOW SHOWERS SINCE THE THERMAL
TROUGH STAYS IN THE VCNTY. HIGH PRESSURE SLIDES OVERHEAD TO START
THE WEEKEND SO LOOKING FOR DRY AND MUCH WARMER CONDITIONS ON
SATURDAY. WINDS BECOME SOUTHWEST AS RIDGE PASSES SATURDAY AFTN.
MIXING TO H9 WOULD SUPPORT HIGHS WELL INTO THE 50S OVER MOST CWA. BY
LATE WEEKEND...UPPER PATTERN SHOWS LARGER TROUGH OVER WESTERN CANADA
AND NORTHWEST CONUS...WITH MORE COMPACT UPPER LOW TRACKING OVER THE
SOUTHWEST CONUS. THERE IS A LOT OF UNCERTAINTY IN HOW THAT SOUTHERN
STREAM WAVE EVOLVES. PREVIOUS ECMWF SHOWED A WRAPPED UP SFC LOW OVER
THE CNTRL PLAINS...WHILE THE 12Z ECMWF SHOWS NOTHING OF THE SORT.
ESSENTIALLY...SEE NO REASON TO STRAY FM CONSENSUS BEYOND THE LATE
WEEK SYSTEM GIVEN THE BIGGER UNCERTAINTY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 729 PM EDT TUE APR 7 2015
A STEADY ENE WIND ON THE SRN FLANK OF A HIGH PRES RIDGE EXTENDING
ACROSS NRN ONTARIO WILL CONTINUE TO ADVECT LOW-LEVEL DRY AIR INTO
UPPER MI THRU THE EVENING HOURS...RESULTING IN VFR CONDITIONS AT
KIWD/KCMX/KSAW DESPITE CONSIDERABLE MID/HIGH CLDS. AS A DISTURBANCE
MOVES INTO THE GREAT LAKES TONIGHT...LIGHT PCPN WILL PROBABLY AFFECT
ALL TERMINALS LATE TONIGHT INTO WED MORNING. ALONG WITH -SN...THERE
MAY BE SOME -RA/-FZRA...THOUGH CONFIDENCE IS QUITE LOW ON PTYPE.
EXPECT MVFR CONDITIONS TO EVENTUALLY DEVELOP...AND LINGER THRU THE
END OF THE FCST PERIOD...ALTHOUGH PCPN SHOULD END BY LATE WED
MORNING/WED AFTERNOON IN THE WAKE OF THE DISTURBANCE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 448 PM EDT TUE APR 7 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HIGH PRES THAT WILL MOVE
FROM NRN ONTARIO INTO QUEBEC THRU WED AND A WARM FRONT THAT
WILL REMAIN TO THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO
NE WINDS WILL PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE
STRONGEST OVER WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE
ISLANDS AND MN NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE
THE WINDS. IN THAT AREA...EXPECT NE WINDS OF 20-30KT TONIGHT...WITH
SOME GALE FORCE GUSTS TO AROUND 35 KT THRU THE EVENING. E TO NE
WINDS...MOSTLY 10-20KT...WILL THEN CONTINUE ON WED AND ON INTO THU
AS LOW PRES LIFTS NE FROM THE CENTRAL PLAINS INTO THE GREAT LAKES
REGION. AT THIS TIME...IT APPEARS THE LOW WILL NOT BE STRONG ENOUGH
TO RESULT IN GALES AS THE LOW APPROACHES AND THEN DEPARTS. WINDS
WILL BACK TO THE N THU AND THEN NW 20-30KT THU NIGHT INTO FRI AS THE
LOW SHIFTS TO THE E AND HIGH PRES BUILDS INTO THE PLAINS. A PERIOD
OF LIGHT WINDS WILL OCCUR FRI NIGHT INTO SAT AS HIGH PRES RIDGE
MOVES ACROSS THE UPPER LAKES. S WINDS WILL THEN BE ON THE INCREASE
TO AT LEAST 10-20KT ON SUN AS THE RIDGE SHIFTS E AND A LOW PRES TROF
MOVES E TO THE UPPER MISSISSIPPI VALLEY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
430 PM EDT MON APR 6 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 429 PM EDT MON APR 6 2015(TODAY AND TONIGHT)
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW CONFLUENT WESTERLY FLOW
ACROSS THE UPPER LAKES BTWN NRN BRANCH TROF OVER ERN CANADA AND SRN
BRANCH RIDGE OVER THE CNTRL CONUS WHICH IS DOWNSTREAM OF A STRONG
TROF ALONG/JUST OFF THE W COAST. SNOW THAT AFFECTED MUCH OF SRN
UPPER MI LAST NIGHT/EARLIER TODAY HAS LARGELY ENDED AS SUBTLE
SHORTWAVE/STRONGER RIGHT ENTRANCE FORCING FROM UPPER JET ALONG AND
LOW/MID LEVEL FRONTOGENESIS HAVE SHIFTED E. TO THE N...A DRY AIR
MASS ASSOCIATED WITH SFC HIGH PRES RIDGING FROM
SASKATCHEWAN/MANITOBA INTO NRN ONTARIO/NRN LAKE SUPERIOR CONTINUES
TO FEED TO THE S AND W.
RIGHT ENTRANCE OF THE UPPER JET WITHIN THE CONFLUENCE ZONE REMAINS
OVER THE UPPER MISSISSIPPI VALLEY/UPPER LAKES REGION TONIGHT. THERE
ARE SOME HINTS THAT ANOTHER SUBTLE SHORTWAVE AND RIBBON OF
FRONTOGENESIS WILL STREAK ACROSS FAR SCNTRL UPPER MI THIS EVENING.
THIS MAY LEAD TO ANOTHER BAND OF SNOW STREAKING ACROSS MAINLY
MENOMINEE COUNTY. LATEST RAP/HRRR SUPPORT THIS IDEA AS DO THE 12Z
NAM AND HIRES WRF-ARW/NMM TO VARYING DEGREES. RADAR TRENDS UPSTREAM
LEND SOME SUPPORT AS WELL. WILL SHOW AN UPTICK IN POPS ACROSS THE
SRN HALF OF MENOMINEE COUNTY THIS EVENING WITH SNOW ACCUMULATIONS
PROBABLY LESS THAN 1 INCH. EXPECT A SHARP CUTOFF TO THE SNOW FARTHER
N AS DRIER AIR FROM THE HIGH PRES RIDGE TO THE N AND NE CONTINUES TO
ADVECT S AND W. WILL CARRY SCHC POPS AS FAR N AS US-2 FROM IRON
RIVER TO ESCANABA. SNOW WILL END OVERNIGHT. EXPECT MIN TEMPS IN THE
20S ACROSS THE AREA...THOUGH SOME TEENS ARE POSSIBLE IN THE USUAL
COLDER SPOTS ACROSS THE N AND E AS CLOUDS MAY THIN ENOUGH TO AID
COOLING OVERNIGHT.
QUIET DAY EXPECTED ON TUE AS ALL MODEL GUIDANCE IS IN GOOD AGREEMENT
ON DRY AIR DOMINATING IN THE LOWER LEVELS. FAVORED THE LOWER SIDE OF
GUIDANCE FOR TEMPS WITH THE IDEA THAT FAIRLY THICK HIGHER CLOUDS
WILL PREVENT SIGNIFICANT WARMING. E TO NE WIND ALSO ARGUES FOR THE
COOLER SIDE OF GUIDANCE...ESPECIALLY SO FROM THE KEWEENAW ACROSS THE
NCNTRL AND S OF KESC NEAR LAKE MI. LOW TO MID 30S SHOULD BE THE RULE
IN THOSE AREAS. ELSEWHERE...TEMPS SHOULD RISE TO AROUND 40F...
HIGHEST WHERE E TO NE WINDS DOWNSLOPE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 356 PM EDT MON APR 6 2015
THE LONG TERM FORECAST CONTINUES TO BE A CONTINUALLY FRUSTRATING
EXPERIENCE WHEN ATTEMPTING TO PIN DOWN THE FINER DETAILS OF THE
FORECAST. ESPECIALLY WITH THE UPPER GREAT LAKES REGION ON THE
NORTHERN EDGE OF THE DISTURBANCES AND HAVING THERMAL PROFILES THAT
SUPPORT MIXED PRECIPITATION AND FREEZING RAIN.
TUE NIGHT INTO WED MORNING A SHORTWAVE LOOKS TO MOVE S OF THE AREA
OR OVER THE SRN CWA. STILL LOTS OF UNCERTAINTY WITH TRACK OF THE
SHORTWAVE...LOCATION AND AMOUNT OF QPF...AND TEMPERATURE PROFILES.
THEREFORE...PRECIP AMOUNT AND TYPE ARE VERY MUCH IN QUESTION AS
WELL. IF THE COLDER GFS/ECMWF SOLUTION VERIFY...ANY PRECIP THAT
FALLS WOULD BE MORE SNOW TRANSITIONING TO FREEZING DRIZZLE AS MID
LEVEL MOISTURE CUTS OUT AND E WINDS FORCE ONSHORE/UPSLOPE PRECIP
INTO SCENTRAL UPPER MI. THE WARMER ALOFT NAM AND GEM WOULD RESULT IN
MORE FREEZING RAIN TURNING TO FREEZING DRIZZLE. THIS BEING
SAID...THE SNOW OR RAIN PORTION IS STILL QUITE UNCERTAIN. FREEZING
DRIZZLE WED MORNING SHOULD BE LIGHT AS LOW LEVEL MIXING SHOULD ALLOW
NEAR SFC LAYERS TO DRY OUT SOME.
WED AFTERNOON/EVENING LOOKS DRY INLAND...BUT COULD SEE DRIZZLE IN
UPSLOPE AREAS FROM THE E WINDS...MAINLY CENTRAL UPPER MI AND THE
KEWEENAW.
A STRONGER SHORTWAVE AND SFC LOW WILL EJECT OUT OF THE CENTRAL
PLAINS WED NIGHT...BRINGING A SURGE OF WARM AIR OVER THE CWA. MODELS
DO NOT AGREE WELL ON THE FINER DETAILS AND DO NOT HAVE GOOD RUN TO
RUN CONTINUITY. MAIN CONCERN EARLY IN THE EVENT IS WITH FREEZING
RAIN POTENTIAL WED NIGHT INTO THU MORNING. MID LEVEL TEMPS WILL
EASILY SUPPORT ALL LIQUID PRECIP...WITH SFC TEMPS DETERMINING
FREEZING RAIN POTENTIAL AS LOW LEVEL COLD AIR WILL BE TOO SHALLOW
FOR SLEET. FREEZING RAIN DOES LOOK LIKE A STRONG POSSIBILITY DURING
THIS TIME...BUT AMOUNTS OF QPF ARE STILL VERY MUCH IN QUESTION. IT
LOOKS AS THOUGH THE SYSTEM WILL PHASE WITH A NRN STREAM SYSTEM LATER
THU INTO FRI...BRINGING COLDER AIR IN FROM THE WNW LATE THU INTO
FRI. THIS FORECAST PERIOD IS EVEN MORE IN QUESTION AS MODELS
STRUGGLE WITH PHASING. IT DOES APPEAR PRECIP IS LIKELY...THE
UNCERTAINTY HAS MORE TO DO WITH PTYPE AND PRECIP AMOUNTS...FOR WHICH
SMALLER SCALE DETAILS WILL BE CRUCIAL. GIVEN THE GENERAL CONSENSUS
IDEA...THINK THAT PRECIP WILL TRANSITION FROM RAIN TO FREEZING RAIN
TO SNOW OVER WRN UPPER MI THU EVENING/NIGHT...WITH SIGNIFICANT
AMOUNTS OF EACH POSSIBLE BUT NOT CERTAIN. RAIN SHOULD TRANSITION TO
MORE OF A RAIN/SNOW MIX OVER THE CENTRAL THU NIGHT. THE ECMWF MOVES
THE PRECIP OUT OF THE AREA FRI EVENING WHILE THE GFS LINGERS PRECIP
INTO SAT MORNING. GIVEN POTENTIAL FOR FREEZING RAIN ACCUMULATION WED
NIGHT/THU MORNING AND FREEZING RAIN/SNOW POTENTIAL THU EVENING/NIGHT
WILL CONTINUE TO HIGHLIGHT IN THE HWO.
IT LOOKS LIKE SFC HIGH PRESSURE AND UPPER RIDGING SHIFT ACROSS THE
CWA OVER THE WEEKEND...WITH A WARM UP POSSIBLE AS THE HIGH SHIFTS E
AND A TROUGH MOVES TOWARD THE AREA FROM THE W. WILL JUST RUN WITH A
CONSENSU OF GUIDANCE FOR SAT-MON.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 139 PM EDT MON APR 6 2015
HIGH PRES RIDGE EXTENDING ACROSS NRN ONTARIO WILL ADVECT LOW-LEVEL
DRY AIR S AND W ACROSS UPPER MI THROUGH TUE MORNING. AS A
RESULT...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS
FCST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT MON APR 6 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HIGH PRES THAT WILL MOVE ACROSS
NRN ONTARIO INTO QUEBEC THRU WED MORNING AND A WARM FRONT THAT WILL
REMAIN TO THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO NE
WINDS WILL PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE
STRONGEST OVER WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE
ISLANDS AND MN NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE
THE WINDS. IN THAT AREA...15-25KT WINDS WILL INCREASE TO 20-30KT
LATER TONIGHT AND CONTINUE THRU TUE NIGHT. EXPECT SOME GALE FORCE
GUSTS TUE AFTN/EVENING. E TO NE WINDS...MOSTLY 15-25KT...WILL THEN
CONTINUE THRU WED AND ON INTO THU AS LOW PRESSURE LIFTS NE FROM THE
CENTRAL PLAINS TO THE GREAT LAKES REGION. AT THIS TIME...IT DOES NOT
APPEAR THAT THE LOW WILL BE STRONG ENOUGH TO RESULT IN GALES AS IT
APPROACHES AND THEN DEPARTS. WINDS WILL BACK AROUND TO THE N AND NW
THU NIGHT AND FRI AS THE LOW EXITS TO THE NE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
356 PM EDT MON APR 6 2015
.UPDATE...
ISSUED AT 654 AM EDT MON APR 6 2015
BASED ON PERSISTENCE OF HIER RADAR ECHOES/LOWER VSBY ALONG THE WI
BORDER WITHIN RATHER NARROW FGEN BAND AS WELL AS SOME HEAVIER SN
REPORTS JUST S OF THE WI BORDER THAT ARE MORE IN LINE WITH THE HIER
QPF SHOWN BY THE VARIOUS HI RES MODELS...OPTED TO ISSUE ADVY FOR
IRON...DICKINSON AND DELTA COUNTIES FOR AS MUCH AS 4 TO PERHAPS 5
INCHES. STILL LOOKS LIKE THE STEADIER SN WL DIMINSH BY MID MRNG WITH
PASSAGE OF DISTURBANCE TO THE E.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 437 AM EDT MON APR 6 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A CONFLUENT W FLOW
OVER THE UPR LKS BTWN ARCTIC BRANCH CLOSED LO OVER NRN QUEBEC AND
POLAR/SUBTROPICAL BRANCH UPR RDG IN THE NRN PLAINS. THERE IS A SHARP
H85 WARM FNT ORIENTED W-E ACRS THE UPR MIDWEST SEPARATING THE VERY
COLD AIR OVER ONTARIO...WHERE THE 00Z H85 TEMP WAS -16C AT YPL FROM
MUCH WARMER AIR IN THE CENTRAL CONUS...WHERE THE 00Z H85 TEMP WAS 9C
AT OMAHA. A RATHER NARROW W-E BAND OF SN IN THE GENERAL ISENTROPIC
ASCENT N OF THE WARM FNT AND UNDER SOME UPR DVGC IN RRQ OF 120KT H3
JET MAX IN SE CANADA IS ORIENTED FM CENTRAL MN ACRS NRN WI INTO MNM
COUNTY EARLY THIS MRNG ALONG AXIS OF SHARPEST FGEN BEST DEFINED IN
THE H7-6 LYR. BUT OVERALL DRYNESS OF THE LLVL AIRMASS IN THE AREA...
ESPECIALLY IN AREAS TO THE N CLOSER TO SFC HI PRES ORIENTED FM SRN
MANITOBA ACRS FAR NRN LK SUP AND INTO SW QUEBEC...IS LIMITING THE
COVERAGE OF THE PCPN TO A FAIRLY NARROW BAND. LATEST RADAR IMAGERY
INDICATES INCRSG REFLECTIVITIES IN MN AHEAD OF A SHRTWV MOVING E
THRU THE NRN PLAINS AS INDICATED ON WV IMAGERY.
MAIN FCST CONCERNS IN THE SHORT TERM WL FOCUS ON POPS/SN AMOUNTS
OVER MAINLY THE SRN TIER COUNTIES THIS MRNG ASSOCIATED WITH NARROW
BAND OF SN AND NEEDED HEADLINES.
TODAY...SHRTWV/AREA OF DEEP LYR QVECTOR CNVGC NOW BRINGING
ENHANCEMENT TO THE PCPN OVER MN AND NRN WI IS FCST TO SLIDE E EARLY
THIS MRNG...BRINGING A PERIOD OF MORE FOCUSED DYNAMIC SUPPORT TO THE
CWA MAINLY TRHU MID MRNG. RECENT RADAR TRENDS SHOWING SOME
INTENSIFICATION OF THE ECHOES IN NW WI SUPPORT SOME OF THE RECENT
HIER RES MODEL FCSTS LIKE THE 00Z NAM OF THE HIER QPF UP TO ABOUT
0.30-0.35 INCH DRIFTING FARTHER TO THE N INTO THE WI BORDER
COUNTIES...A QPF CONSISTENT WITH THE 3 G/KG SPECIFIC HUMIDITY
PRESENT ARND H7. RATHER HI...NARROW DGZ SHOWN ON FCST SDNGS WL NOT
SUPPORT SN/WATER RATIO MUCH HIER THAN 10:1 IN THIS AREA. CONSIDERING
ADDING THESE COUNTIES TO ADVY...BUT POTENTIAL IMPACT OF LLVL DRY AIR
TO THE N THAT MIGHT LOWER THE QPF TO WHAT IS SHOWN ON SOME OF THE
OTHER HI RES MODELS LIKE THE HRRR INDICATE AN SPS FOR UP TO ABOUT 3
INCHES NEAR THE BORDER IN IRON AND DICKINSON COUNTIES AS WELL
AS DELTA COUNTY MIGHT BE A BETTER STATEGY. WL MAINTAIN THE WINTER WX
ADVY FOR MENOMINEE COUNTY. SINCE FCST SDNGS DO NOT SHOW AN ELEVATED
WARM LYR THAT FEATURES TEMPS ABOVE 0C...REMOVED THE MENTION OF MIXED
PCPN THIS MRNG. THE EXTENT OF THE DRY AIR TO THE N WL LIKELY RESULT
IN A SHARPER NRN EDGE OF THE MORE SGNFT PCPN THAN IS SHOWN BY THE
MODELS. ARRIVAL OF QVECTOR DVGC/SUBSIDENCE IN THE WAKE OF THE
PASSING SHRTWV BY LATE MRNG WL CAUSE THE SN BAND TO DIMINISH...WITH
LINGERING LGT PCPN OVER THE SCENTRAL TRANSITIONING TO A MIX OF
SN WITH SOME SPRINKLES/LIGHT RA AS TEMPS RISE INTO THE MID/UPR 30S.
ARRIVAL OF SOME DRIER AIR INTO THE NRN TIER COUNTIES THIS AFTN WL
END ANY LINGERING PCPN THERE EVEN AS SOME CLDS LINGER.
TNGT...ALTHOUGH THERE ARE HINTS ANOTHER SHRTWV/SOME DYNAMIC SUPPORT
WL PUSH INTO THE AREA FM THE W IN THE ZONAL FLOW ALOFT...THE
CONTINUED ARRIVAL OF DRIER LLVL AIR SHOULD LIMIT POPS TO THE
SCENTRAL. TENDED TO CUT POPS FM PREVIOUS FCST ESPECIALLY OVER THE
NRN TIER...WITH NO HIER THAN CHC POPS EVEN NEAR THE WI BORDER.
LINGERING CLDS WL LIMIT THE DIURNAL TEMP FALL EVEN WITH THE ARRIVAL
OF LLVL DRIER AIR.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 356 PM EDT MON APR 6 2015
THE LONG TERM FORECAST CONTINUES TO BE A CONTINUALLY FRUSTRATING
EXPERIENCE WHEN ATTEMPTING TO PIN DOWN THE FINER DETAILS OF THE
FORECAST. ESPECIALLY WITH THE UPPER GREAT LAKES REGION ON THE
NORTHERN EDGE OF THE DISTURBANCES AND HAVING THERMAL PROFILES THAT
SUPPORT MIXED PRECIPITATION AND FREEZING RAIN.
TUE NIGHT INTO WED MORNING A SHORTWAVE LOOKS TO MOVE S OF THE AREA
OR OVER THE SRN CWA. STILL LOTS OF UNCERTAINTY WITH TRACK OF THE
SHORTWAVE...LOCATION AND AMOUNT OF QPF...AND TEMPERATURE PROFILES.
THEREFORE...PRECIP AMOUNT AND TYPE ARE VERY MUCH IN QUESTION AS
WELL. IF THE COLDER GFS/ECMWF SOLUTION VERIFY...ANY PRECIP THAT
FALLS WOULD BE MORE SNOW TRANSITIONING TO FREEZING DRIZZLE AS MID
LEVEL MOISTURE CUTS OUT AND E WINDS FORCE ONSHORE/UPSLOPE PRECIP
INTO SCENTRAL UPPER MI. THE WARMER ALOFT NAM AND GEM WOULD RESULT IN
MORE FREEZING RAIN TURNING TO FREEZING DRIZZLE. THIS BEING
SAID...THE SNOW OR RAIN PORTION IS STILL QUITE UNCERTAIN. FREEZING
DRIZZLE WED MORNING SHOULD BE LIGHT AS LOW LEVEL MIXING SHOULD ALLOW
NEAR SFC LAYERS TO DRY OUT SOME.
WED AFTERNOON/EVENING LOOKS DRY INLAND...BUT COULD SEE DRIZZLE IN
UPSLOPE AREAS FROM THE E WINDS...MAINLY CENTRAL UPPER MI AND THE
KEWEENAW.
A STRONGER SHORTWAVE AND SFC LOW WILL EJECT OUT OF THE CENTRAL
PLAINS WED NIGHT...BRINGING A SURGE OF WARM AIR OVER THE CWA. MODELS
DO NOT AGREE WELL ON THE FINER DETAILS AND DO NOT HAVE GOOD RUN TO
RUN CONTINUITY. MAIN CONCERN EARLY IN THE EVENT IS WITH FREEZING
RAIN POTENTIAL WED NIGHT INTO THU MORNING. MID LEVEL TEMPS WILL
EASILY SUPPORT ALL LIQUID PRECIP...WITH SFC TEMPS DETERMINING
FREEZING RAIN POTENTIAL AS LOW LEVEL COLD AIR WILL BE TOO SHALLOW
FOR SLEET. FREEZING RAIN DOES LOOK LIKE A STRONG POSSIBILITY DURING
THIS TIME...BUT AMOUNTS OF QPF ARE STILL VERY MUCH IN QUESTION. IT
LOOKS AS THOUGH THE SYSTEM WILL PHASE WITH A NRN STREAM SYSTEM LATER
THU INTO FRI...BRINGING COLDER AIR IN FROM THE WNW LATE THU INTO
FRI. THIS FORECAST PERIOD IS EVEN MORE IN QUESTION AS MODELS
STRUGGLE WITH PHASING. IT DOES APPEAR PRECIP IS LIKELY...THE
UNCERTAINTY HAS MORE TO DO WITH PTYPE AND PRECIP AMOUNTS...FOR WHICH
SMALLER SCALE DETAILS WILL BE CRUCIAL. GIVEN THE GENERAL CONSENSUS
IDEA...THINK THAT PRECIP WILL TRANSITION FROM RAIN TO FREEZING RAIN
TO SNOW OVER WRN UPPER MI THU EVENING/NIGHT...WITH SIGNIFICANT
AMOUNTS OF EACH POSSIBLE BUT NOT CERTAIN. RAIN SHOULD TRANSITION TO
MORE OF A RAIN/SNOW MIX OVER THE CENTRAL THU NIGHT. THE ECMWF MOVES
THE PRECIP OUT OF THE AREA FRI EVENING WHILE THE GFS LINGERS PRECIP
INTO SAT MORNING. GIVEN POTENTIAL FOR FREEZING RAIN ACCUMULATION WED
NIGHT/THU MORNING AND FREEZING RAIN/SNOW POTENTIAL THU EVENING/NIGHT
WILL CONTINUE TO HIGHLIGHT IN THE HWO.
IT LOOKS LIKE SFC HIGH PRESSURE AND UPPER RIDGING SHIFT ACROSS THE
CWA OVER THE WEEKEND...WITH A WARM UP POSSIBLE AS THE HIGH SHIFTS E
AND A TROUGH MOVES TOWARD THE AREA FROM THE W. WILL JUST RUN WITH A
CONSENSU OF GUIDANCE FOR SAT-MON.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 139 PM EDT MON APR 6 2015
HIGH PRES RIDGE EXTENDING ACROSS NRN ONTARIO WILL ADVECT LOW-LEVEL
DRY AIR S AND W ACROSS UPPER MI THROUGH TUE MORNING. AS A
RESULT...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS
FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT MON APR 6 2015
WITH LAKE SUPERIOR SITUATED BETWEEN A HIGH IN SOUTHERN CANADA AND A
WARM FRONT OVER THE LOWER GREAT LAKES...EXPECT EAST TO NORTHEAST
WINDS TO PERSIST THROUGH WEDNESDAY NIGHT. MOST OF THE TIME...WINDS
WILL BE BELOW 25KTS...BUT FUNNELING DOWN THE WESTERN THIRD OF
LAKE SUPERIOR ON TUESDAY COULD PRODUCE GUSTS TO 30KTS. A LOW
PRESSURE SYSTEM LIFTING NORTHEAST OUT OF THE CENTRAL PLAINS WILL
MOVE THROUGH THE GREAT LAKES REGION ON FRIDAY THERE COULD BE
NORTH-NORTHEAST GUSTS TO 25 KNOTS AS IT MOVES THROUGH ON FRIDAY
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
139 PM EDT MON APR 6 2015
.UPDATE...
ISSUED AT 654 AM EDT MON APR 6 2015
BASED ON PERSISTENCE OF HIER RADAR ECHOES/LOWER VSBY ALONG THE WI
BORDER WITHIN RATHER NARROW FGEN BAND AS WELL AS SOME HEAVIER SN
REPORTS JUST S OF THE WI BORDER THAT ARE MORE IN LINE WITH THE HIER
QPF SHOWN BY THE VARIOUS HI RES MODELS...OPTED TO ISSUE ADVY FOR
IRON...DICKINSON AND DELTA COUNTIES FOR AS MUCH AS 4 TO PERHAPS 5
INCHES. STILL LOOKS LIKE THE STEADIER SN WL DIMINSH BY MID MRNG WITH
PASSAGE OF DISTURBANCE TO THE E.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 437 AM EDT MON APR 6 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A CONFLUENT W FLOW
OVER THE UPR LKS BTWN ARCTIC BRANCH CLOSED LO OVER NRN QUEBEC AND
POLAR/SUBTROPICAL BRANCH UPR RDG IN THE NRN PLAINS. THERE IS A SHARP
H85 WARM FNT ORIENTED W-E ACRS THE UPR MIDWEST SEPARATING THE VERY
COLD AIR OVER ONTARIO...WHERE THE 00Z H85 TEMP WAS -16C AT YPL FROM
MUCH WARMER AIR IN THE CENTRAL CONUS...WHERE THE 00Z H85 TEMP WAS 9C
AT OMAHA. A RATHER NARROW W-E BAND OF SN IN THE GENERAL ISENTROPIC
ASCENT N OF THE WARM FNT AND UNDER SOME UPR DVGC IN RRQ OF 120KT H3
JET MAX IN SE CANADA IS ORIENTED FM CENTRAL MN ACRS NRN WI INTO MNM
COUNTY EARLY THIS MRNG ALONG AXIS OF SHARPEST FGEN BEST DEFINED IN
THE H7-6 LYR. BUT OVERALL DRYNESS OF THE LLVL AIRMASS IN THE AREA...
ESPECIALLY IN AREAS TO THE N CLOSER TO SFC HI PRES ORIENTED FM SRN
MANITOBA ACRS FAR NRN LK SUP AND INTO SW QUEBEC...IS LIMITING THE
COVERAGE OF THE PCPN TO A FAIRLY NARROW BAND. LATEST RADAR IMAGERY
INDICATES INCRSG REFLECTIVITIES IN MN AHEAD OF A SHRTWV MOVING E
THRU THE NRN PLAINS AS INDICATED ON WV IMAGERY.
MAIN FCST CONCERNS IN THE SHORT TERM WL FOCUS ON POPS/SN AMOUNTS
OVER MAINLY THE SRN TIER COUNTIES THIS MRNG ASSOCIATED WITH NARROW
BAND OF SN AND NEEDED HEADLINES.
TODAY...SHRTWV/AREA OF DEEP LYR QVECTOR CNVGC NOW BRINGING
ENHANCEMENT TO THE PCPN OVER MN AND NRN WI IS FCST TO SLIDE E EARLY
THIS MRNG...BRINGING A PERIOD OF MORE FOCUSED DYNAMIC SUPPORT TO THE
CWA MAINLY TRHU MID MRNG. RECENT RADAR TRENDS SHOWING SOME
INTENSIFICATION OF THE ECHOES IN NW WI SUPPORT SOME OF THE RECENT
HIER RES MODEL FCSTS LIKE THE 00Z NAM OF THE HIER QPF UP TO ABOUT
0.30-0.35 INCH DRIFTING FARTHER TO THE N INTO THE WI BORDER
COUNTIES...A QPF CONSISTENT WITH THE 3 G/KG SPECIFIC HUMIDITY
PRESENT ARND H7. RATHER HI...NARROW DGZ SHOWN ON FCST SDNGS WL NOT
SUPPORT SN/WATER RATIO MUCH HIER THAN 10:1 IN THIS AREA. CONSIDERING
ADDING THESE COUNTIES TO ADVY...BUT POTENTIAL IMPACT OF LLVL DRY AIR
TO THE N THAT MIGHT LOWER THE QPF TO WHAT IS SHOWN ON SOME OF THE
OTHER HI RES MODELS LIKE THE HRRR INDICATE AN SPS FOR UP TO ABOUT 3
INCHES NEAR THE BORDER IN IRON AND DICKINSON COUNTIES AS WELL
AS DELTA COUNTY MIGHT BE A BETTER STATEGY. WL MAINTAIN THE WINTER WX
ADVY FOR MENOMINEE COUNTY. SINCE FCST SDNGS DO NOT SHOW AN ELEVATED
WARM LYR THAT FEATURES TEMPS ABOVE 0C...REMOVED THE MENTION OF MIXED
PCPN THIS MRNG. THE EXTENT OF THE DRY AIR TO THE N WL LIKELY RESULT
IN A SHARPER NRN EDGE OF THE MORE SGNFT PCPN THAN IS SHOWN BY THE
MODELS. ARRIVAL OF QVECTOR DVGC/SUBSIDENCE IN THE WAKE OF THE
PASSING SHRTWV BY LATE MRNG WL CAUSE THE SN BAND TO DIMINISH...WITH
LINGERING LGT PCPN OVER THE SCENTRAL TRANSITIONING TO A MIX OF
SN WITH SOME SPRINKLES/LIGHT RA AS TEMPS RISE INTO THE MID/UPR 30S.
ARRIVAL OF SOME DRIER AIR INTO THE NRN TIER COUNTIES THIS AFTN WL
END ANY LINGERING PCPN THERE EVEN AS SOME CLDS LINGER.
TNGT...ALTHOUGH THERE ARE HINTS ANOTHER SHRTWV/SOME DYNAMIC SUPPORT
WL PUSH INTO THE AREA FM THE W IN THE ZONAL FLOW ALOFT...THE
CONTINUED ARRIVAL OF DRIER LLVL AIR SHOULD LIMIT POPS TO THE
SCENTRAL. TENDED TO CUT POPS FM PREVIOUS FCST ESPECIALLY OVER THE
NRN TIER...WITH NO HIER THAN CHC POPS EVEN NEAR THE WI BORDER.
LINGERING CLDS WL LIMIT THE DIURNAL TEMP FALL EVEN WITH THE ARRIVAL
OF LLVL DRIER AIR.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 422 AM EDT MON APR 6 2015
THE LONG TERM FORECAST CONTINUES TO BE A FRUSTRATING EXPERIENCE WHEN
ATTEMPTING TO PIN DOWN THE FINER DETAILS OF THE FORECAST. ESPECIALLY
WITH THE UPPER GREAT LAKES REGION ON THE NORTHERN EDGE OF THE
DISTURBANCES AND HAVING THERMAL PROFILES THAT SUPPORT MIXED
PRECIPITATION AND FREEZING RAIN.
THE START OF THE LONG TERM FORECAST HAS THE UPPER GREAT LAKES REGION
BETWEEN A HIGH MOVING EAST ACROSS ONTARIO AND THE WARM FRONT DRAPED
FROM WEST TO EAST ACROSS THE LOWER GREAT LAKES REGION. WITH THIS
WARM FRONT SLOWLY SINKING SOUTH ON TUESDAY...WOULD EXPECT THE BULK
OF THE PRECIPITATION TO STAY SOUTH OF THE CWA...BUT THE AREA
CONTINUES TO SEE WEAK SHORTWAVE EJECTING OUT OF THE UPPER TROUGH
OVER THE WESTERN CONUS AND THROUGH THE REGION. WITH THE FLUCTUATIONS
IN THE MODELS OVER THE LAST SEVERAL DAYS...WILL OPT TO TREND THE
FORECAST IN THE LATEST DIRECTIONS WITH OUT GETTING TOO SPECIFIC.
THEREFORE FOR TUESDAY...THINK THE DRY AIR (BETWEEN 850-750MB)
ASSOCIATED WITH THE HIGH MOVING THROUGH ONTARIO WILL KEEP THE
NORTHEAST HALF OF THE CWA DRY WHILE THE AREA ALONG THE WISCONSIN
BORDER MAY SEE SOME LIGHT PRECIPITATION ON THE NORTHERN EDGE OF THE
850-700MB WARM AIR ADVECTION INITIALLY IN THE MORNING. ALTHOUGH
THERE ARE SOME HINTS OF THE ICE CRYSTALS CUTTING OUT...OPTED TO KEEP
P-TYPE AS SNOW DUE THE THE AMOUNT OF DRYING OCCURRING IN THE
MORNING. ALTHOUGH THAT DRY AIR IS MOVING IN...THERE SHOULD BE ENOUGH
FORCING/MOISTURE WITH THE SOUTHWESTERLY FLOW AROUND 700-600MB TO
SUPPORT CLOUDS OVER THE SOUTHWEST 2/3RDS OF THE CWA.
AS THE SURFACE LOW THAT IS CURRENTLY IN THE LEE OF THE CENTRAL
ROCKIES IS SHIFTING EAST THROUGH THE CENTRAL PLAINS...ANOTHER
STRONGER SHORTWAVE LIFTS EAST-NORTHEAST THROUGH THE GREAT LAKES
REGION TUESDAY NIGHT. AT THIS STAGE...THINK THE HEAVIEST
PRECIPITATION WILL STAY TO THE SOUTH-SOUTHEAST OF THE AREA (TRACKING
THROUGH NORTHEAST WISCONSIN AND INTO NORTHERN LOWER MICHIGAN). BUT
THERE SHOULD STILL BE ENOUGH SUPPORT FOR CHANCES OVER THE SOUTH
CENTRAL AND SLIGHT CHANCES FOR MUCH OF THE REST OF THE U.P. LOOKING
AT THE FORECAST SOUNDINGS...EXPECT MUCH OF THIS PRECIP TO FALL AS
SNOW...BUT THERE MAY BE ENOUGH MID LEVEL WARMING OVER SOUTHERN
MENOMINEE COUNTY TO PARTIALLY MELT THE SNOWFLAKES...LEADING TO SOME
SLEET OR MAYBE EVEN FREEZING RAIN. THAT WAVE QUICKLY DEPARTS LATE
TUESDAY NIGHT INTO WEDNESDAY MORNING...SO WOULD EXPECT A DRYING
TREND AS THE DEEPER MOISTURE DEPARTS AND A HIGH PRESSURE RIDGE (FROM
THE HIGH TO THE NORTHEAST OF JAMES BAY) SWINGS EAST ACROSS THE CWA.
THAT WILL MAINTAIN THE DRY CONDITIONS THROUGH AT LEAST WEDNESDAY
EVENING.
AS THE UPPER LOW LIFTS INTO THE CENTRAL ROCKIES ON WEDNESDAY
NIGHT...THE NEXT WAVE WILL EJECT TOWARDS THE REGION UNDER THE
SOUTHWESTERLY FLOW ALOFT. IN ADDITION TO THE SHORTWAVE...WARM AIR
WILL SURGE NORTH OVER THE REGION...WITH 850-800MB TEMPS WARMING
ABOVE 5C. THUS...ANY PRECIPITATION THAT FALLS THROUGH THIS WARM
LAYER WILL MELT AND THE P-TYPE WILL DEPEND ON THE NEAR SURFACE
TEMPERATURES. WITH THE EXISTING COLD AIR FROM THE DEPARTING
HIGH...WOULD EXPECT PRIMARILY FREEZING RAIN FOR THE START OF THE
EVENT (LOWEST 2KFT ARE BELOW FREEZING)...AS IT DOESN/T LOOK LIKE
THERE WILL BE ENOUGH COLD AIR NEAR THE SURFACE FOR SLEET. THE
ARRIVAL TIME OF THE PRECIPITATION AND SURFACE TEMPERATURES WILL BE
CRUCIAL FOR THE LATE WEDNESDAY NIGHT INTO THURSDAY FORECAST AS
TEMPERATURES LOOK TO BE AT OR SLIGHTLY BELOW FREEZING THROUGH MID
MORNING BEFORE WARMING SLIGHTLY THROUGH THE DAY. WILL CONTINUE TO
SHOW HIGH CHANCE OR EVEN LIKELY POPS ACROSS THE AREA STARTING VERY
LATE WEDNESDAY NIGHT AND REMAINING THROUGH THURSDAY.
HOPEFULLY...MODELS WILL CLOSE IN ON THE LOCATION OF THE BEST
PRECIPITATION FOR THIS PERIOD...AS IT APPEARS TO BE A DECENT
OPPORTUNITY FOR FREEZING RAIN ACROSS THE U.P.. WILL CONTINUE TO
MENTION THIS THREAT IN THE HWO AND WITH THE INCREASING CONFIDENCE
START TO PROVIDE A LITTLE MORE DETAIL.
THE UPPER LOW WILL CONTINUE TO LIFT NORTHEAST TOWARDS THE AREA
THURSDAY NIGHT AND THROUGH THE UPPER GREAT LAKES
FRIDAY/SATURDAY...BUT MODELS STILL DIFFERING ON THE DETAILS. WHILE
THE CONSISTENCY IS LACKING...THE LATEST TRENDS WITH THE 00Z MODELS
IS FOR A QUICKER LIFT TO THE NORTHEAST OF THE UPPER LOW/TROUGH WHICH
WOULD ALLOW IT TO PHASE WITH THE NORTHERN STREAM. THE 00Z ECMWF MADE
A SIGNIFICANT JUMP TOWARDS THE FASTER SOLUTION SEEN IN THE PREVIOUS
GFS RUNS. THAT IS A SIGNIFICANT DEPARTURE FROM THE 12Z ECMWF/GEM
ENSEMBLE MEANS...SO IT WILL BE INTERESTING IF THAT TREND CONTINUES.
OVERALL...FELT A GENERAL CONSENSUS OF THE MODELS WAS REASONABLE FOR
THE THURSDAY NIGHT INTO FRIDAY NIGHT PERIOD...WHICH HAS THE NEXT
WAVE OF PRECIPITATION MOVING NORTHEAST ACROSS THE CWA AFTER MIDNIGHT
THURSDAY NIGHT AND CONTINUING INTO FRIDAY. WITH THE FASTER AND
FARTHER SOUTHEAST TRACK OF THE SURFACE LOW...A TRANSITION FROM RAIN
OR FREEZING RAIN WILL OCCUR OVER THE WESTERN HALF OF UPPER MICHIGAN
ON FRIDAY. THERE COULD BE SOME MEASURABLE ACCUMULATIONS OVER THE
WEST...BUT IT IS STILL WAY TO FAR OUT AND UNCERTAIN TO HAVE AN
INDICATION ON AMOUNTS.
DEPENDING ON HOW QUICKLY THE SYSTEM MOVES THROUGH THE
AREA...SATURDAY COULD SEE SOME LINGERING PRECIPITATION.
OTHERWISE...IT LOOKS LIKE MUCH OF THE WEEKEND WILL BE DRY. ANOTHER
STRONG SYSTEM DROPS SOUTHEAST OUT OF THE GULF OF ALASKA ON SATURDAY
MORNING AND INTO THE NORTHERN PLAINS ON SUNDAY NIGHT. THAT SETS THE
STAGE FOR AN ACTIVE START TO THE NEXT WORK WEEK (RAINY AND POSSIBLY
SOME THUNDERSTORMS FOR MONDAY BEFORE CHANGING TO SNOW ON THE
BACKSIDE FOR TUESDAY THE 14TH).
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 139 PM EDT MON APR 6 2015
HIGH PRES RIDGE EXTENDING ACROSS NRN ONTARIO WILL ADVECT LOW-LEVEL
DRY AIR S AND W ACROSS UPPER MI THROUGH TUE MORNING. AS A
RESULT...VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS
FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT MON APR 6 2015
WITH LAKE SUPERIOR SITUATED BETWEEN A HIGH IN SOUTHERN CANADA AND A
WARM FRONT OVER THE LOWER GREAT LAKES...EXPECT EAST TO NORTHEAST
WINDS TO PERSIST THROUGH WEDNESDAY NIGHT. MOST OF THE TIME...WINDS
WILL BE BELOW 25KTS...BUT FUNNELING DOWN THE WESTERN THIRD OF
LAKE SUPERIOR ON TUESDAY COULD PRODUCE GUSTS TO 30KTS. A LOW
PRESSURE SYSTEM LIFTING NORTHEAST OUT OF THE CENTRAL PLAINS WILL
MOVE THROUGH THE GREAT LAKES REGION ON FRIDAY THERE COULD BE
NORTH-NORTHEAST GUSTS TO 25 KNOTS AS IT MOVES THROUGH ON FRIDAY
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
753 AM EDT MON APR 6 2015
.UPDATE...
ISSUED AT 654 AM EDT MON APR 6 2015
BASED ON PERSISTENCE OF HIER RADAR ECHOES/LOWER VSBY ALONG THE WI
BORDER WITHIN RATHER NARROW FGEN BAND AS WELL AS SOME HEAVIER SN
REPORTS JUST S OF THE WI BORDER THAT ARE MORE IN LINE WITH THE HIER
QPF SHOWN BY THE VARIOUS HI RES MODELS...OPTED TO ISSUE ADVY FOR
IRON...DICKINSON AND DELTA COUNTIES FOR AS MUCH AS 4 TO PERHAPS 5
INCHES. STILL LOOKS LIKE THE STEADIER SN WL DIMINSH BY MID MRNG WITH
PASSAGE OF DISTURBANCE TO THE E.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 437 AM EDT MON APR 6 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A CONFLUENT W FLOW
OVER THE UPR LKS BTWN ARCTIC BRANCH CLOSED LO OVER NRN QUEBEC AND
POLAR/SUBTROPICAL BRANCH UPR RDG IN THE NRN PLAINS. THERE IS A SHARP
H85 WARM FNT ORIENTED W-E ACRS THE UPR MIDWEST SEPARATING THE VERY
COLD AIR OVER ONTARIO...WHERE THE 00Z H85 TEMP WAS -16C AT YPL FROM
MUCH WARMER AIR IN THE CENTRAL CONUS...WHERE THE 00Z H85 TEMP WAS 9C
AT OMAHA. A RATHER NARROW W-E BAND OF SN IN THE GENERAL ISENTROPIC
ASCENT N OF THE WARM FNT AND UNDER SOME UPR DVGC IN RRQ OF 120KT H3
JET MAX IN SE CANADA IS ORIENTED FM CENTRAL MN ACRS NRN WI INTO MNM
COUNTY EARLY THIS MRNG ALONG AXIS OF SHARPEST FGEN BEST DEFINED IN
THE H7-6 LYR. BUT OVERALL DRYNESS OF THE LLVL AIRMASS IN THE AREA...
ESPECIALLY IN AREAS TO THE N CLOSER TO SFC HI PRES ORIENTED FM SRN
MANITOBA ACRS FAR NRN LK SUP AND INTO SW QUEBEC...IS LIMITING THE
COVERAGE OF THE PCPN TO A FAIRLY NARROW BAND. LATEST RADAR IMAGERY
INDICATES INCRSG REFLECTIVITIES IN MN AHEAD OF A SHRTWV MOVING E
THRU THE NRN PLAINS AS INDICATED ON WV IMAGERY.
MAIN FCST CONCERNS IN THE SHORT TERM WL FOCUS ON POPS/SN AMOUNTS
OVER MAINLY THE SRN TIER COUNTIES THIS MRNG ASSOCIATED WITH NARROW
BAND OF SN AND NEEDED HEADLINES.
TODAY...SHRTWV/AREA OF DEEP LYR QVECTOR CNVGC NOW BRINGING
ENHANCEMENT TO THE PCPN OVER MN AND NRN WI IS FCST TO SLIDE E EARLY
THIS MRNG...BRINGING A PERIOD OF MORE FOCUSED DYNAMIC SUPPORT TO THE
CWA MAINLY TRHU MID MRNG. RECENT RADAR TRENDS SHOWING SOME
INTENSIFICATION OF THE ECHOES IN NW WI SUPPORT SOME OF THE RECENT
HIER RES MODEL FCSTS LIKE THE 00Z NAM OF THE HIER QPF UP TO ABOUT
0.30-0.35 INCH DRIFTING FARTHER TO THE N INTO THE WI BORDER
COUNTIES...A QPF CONSISTENT WITH THE 3 G/KG SPECIFIC HUMIDITY
PRESENT ARND H7. RATHER HI...NARROW DGZ SHOWN ON FCST SDNGS WL NOT
SUPPORT SN/WATER RATIO MUCH HIER THAN 10:1 IN THIS AREA. CONSIDERING
ADDING THESE COUNTIES TO ADVY...BUT POTENTIAL IMPACT OF LLVL DRY AIR
TO THE N THAT MIGHT LOWER THE QPF TO WHAT IS SHOWN ON SOME OF THE
OTHER HI RES MODELS LIKE THE HRRR INDICATE AN SPS FOR UP TO ABOUT 3
INCHES NEAR THE BORDER IN IRON AND DICKINSON COUNTIES AS WELL
AS DELTA COUNTY MIGHT BE A BETTER STATEGY. WL MAINTAIN THE WINTER WX
ADVY FOR MENOMINEE COUNTY. SINCE FCST SDNGS DO NOT SHOW AN ELEVATED
WARM LYR THAT FEATURES TEMPS ABOVE 0C...REMOVED THE MENTION OF MIXED
PCPN THIS MRNG. THE EXTENT OF THE DRY AIR TO THE N WL LIKELY RESULT
IN A SHARPER NRN EDGE OF THE MORE SGNFT PCPN THAN IS SHOWN BY THE
MODELS. ARRIVAL OF QVECTOR DVGC/SUBSIDENCE IN THE WAKE OF THE
PASSING SHRTWV BY LATE MRNG WL CAUSE THE SN BAND TO DIMINISH...WITH
LINGERING LGT PCPN OVER THE SCENTRAL TRANSITIONING TO A MIX OF
SN WITH SOME SPRINKLES/LIGHT RA AS TEMPS RISE INTO THE MID/UPR 30S.
ARRIVAL OF SOME DRIER AIR INTO THE NRN TIER COUNTIES THIS AFTN WL
END ANY LINGERING PCPN THERE EVEN AS SOME CLDS LINGER.
TNGT...ALTHOUGH THERE ARE HINTS ANOTHER SHRTWV/SOME DYNAMIC SUPPORT
WL PUSH INTO THE AREA FM THE W IN THE ZONAL FLOW ALOFT...THE
CONTINUED ARRIVAL OF DRIER LLVL AIR SHOULD LIMIT POPS TO THE
SCENTRAL. TENDED TO CUT POPS FM PREVIOUS FCST ESPECIALLY OVER THE
NRN TIER...WITH NO HIER THAN CHC POPS EVEN NEAR THE WI BORDER.
LINGERING CLDS WL LIMIT THE DIURNAL TEMP FALL EVEN WITH THE ARRIVAL
OF LLVL DRIER AIR.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 422 AM EDT MON APR 6 2015
THE LONG TERM FORECAST CONTINUES TO BE A FRUSTRATING EXPERIENCE WHEN
ATTEMPTING TO PIN DOWN THE FINER DETAILS OF THE FORECAST. ESPECIALLY
WITH THE UPPER GREAT LAKES REGION ON THE NORTHERN EDGE OF THE
DISTURBANCES AND HAVING THERMAL PROFILES THAT SUPPORT MIXED
PRECIPITATION AND FREEZING RAIN.
THE START OF THE LONG TERM FORECAST HAS THE UPPER GREAT LAKES REGION
BETWEEN A HIGH MOVING EAST ACROSS ONTARIO AND THE WARM FRONT DRAPED
FROM WEST TO EAST ACROSS THE LOWER GREAT LAKES REGION. WITH THIS
WARM FRONT SLOWLY SINKING SOUTH ON TUESDAY...WOULD EXPECT THE BULK
OF THE PRECIPITATION TO STAY SOUTH OF THE CWA...BUT THE AREA
CONTINUES TO SEE WEAK SHORTWAVE EJECTING OUT OF THE UPPER TROUGH
OVER THE WESTERN CONUS AND THROUGH THE REGION. WITH THE FLUCTUATIONS
IN THE MODELS OVER THE LAST SEVERAL DAYS...WILL OPT TO TREND THE
FORECAST IN THE LATEST DIRECTIONS WITH OUT GETTING TOO SPECIFIC.
THEREFORE FOR TUESDAY...THINK THE DRY AIR (BETWEEN 850-750MB)
ASSOCIATED WITH THE HIGH MOVING THROUGH ONTARIO WILL KEEP THE
NORTHEAST HALF OF THE CWA DRY WHILE THE AREA ALONG THE WISCONSIN
BORDER MAY SEE SOME LIGHT PRECIPITATION ON THE NORTHERN EDGE OF THE
850-700MB WARM AIR ADVECTION INITIALLY IN THE MORNING. ALTHOUGH
THERE ARE SOME HINTS OF THE ICE CRYSTALS CUTTING OUT...OPTED TO KEEP
P-TYPE AS SNOW DUE THE THE AMOUNT OF DRYING OCCURRING IN THE
MORNING. ALTHOUGH THAT DRY AIR IS MOVING IN...THERE SHOULD BE ENOUGH
FORCING/MOISTURE WITH THE SOUTHWESTERLY FLOW AROUND 700-600MB TO
SUPPORT CLOUDS OVER THE SOUTHWEST 2/3RDS OF THE CWA.
AS THE SURFACE LOW THAT IS CURRENTLY IN THE LEE OF THE CENTRAL
ROCKIES IS SHIFTING EAST THROUGH THE CENTRAL PLAINS...ANOTHER
STRONGER SHORTWAVE LIFTS EAST-NORTHEAST THROUGH THE GREAT LAKES
REGION TUESDAY NIGHT. AT THIS STAGE...THINK THE HEAVIEST
PRECIPITATION WILL STAY TO THE SOUTH-SOUTHEAST OF THE AREA (TRACKING
THROUGH NORTHEAST WISCONSIN AND INTO NORTHERN LOWER MICHIGAN). BUT
THERE SHOULD STILL BE ENOUGH SUPPORT FOR CHANCES OVER THE SOUTH
CENTRAL AND SLIGHT CHANCES FOR MUCH OF THE REST OF THE U.P. LOOKING
AT THE FORECAST SOUNDINGS...EXPECT MUCH OF THIS PRECIP TO FALL AS
SNOW...BUT THERE MAY BE ENOUGH MID LEVEL WARMING OVER SOUTHERN
MENOMINEE COUNTY TO PARTIALLY MELT THE SNOWFLAKES...LEADING TO SOME
SLEET OR MAYBE EVEN FREEZING RAIN. THAT WAVE QUICKLY DEPARTS LATE
TUESDAY NIGHT INTO WEDNESDAY MORNING...SO WOULD EXPECT A DRYING
TREND AS THE DEEPER MOISTURE DEPARTS AND A HIGH PRESSURE RIDGE (FROM
THE HIGH TO THE NORTHEAST OF JAMES BAY) SWINGS EAST ACROSS THE CWA.
THAT WILL MAINTAIN THE DRY CONDITIONS THROUGH AT LEAST WEDNESDAY
EVENING.
AS THE UPPER LOW LIFTS INTO THE CENTRAL ROCKIES ON WEDNESDAY
NIGHT...THE NEXT WAVE WILL EJECT TOWARDS THE REGION UNDER THE
SOUTHWESTERLY FLOW ALOFT. IN ADDITION TO THE SHORTWAVE...WARM AIR
WILL SURGE NORTH OVER THE REGION...WITH 850-800MB TEMPS WARMING
ABOVE 5C. THUS...ANY PRECIPITATION THAT FALLS THROUGH THIS WARM
LAYER WILL MELT AND THE P-TYPE WILL DEPEND ON THE NEAR SURFACE
TEMPERATURES. WITH THE EXISTING COLD AIR FROM THE DEPARTING
HIGH...WOULD EXPECT PRIMARILY FREEZING RAIN FOR THE START OF THE
EVENT (LOWEST 2KFT ARE BELOW FREEZING)...AS IT DOESN/T LOOK LIKE
THERE WILL BE ENOUGH COLD AIR NEAR THE SURFACE FOR SLEET. THE
ARRIVAL TIME OF THE PRECIPITATION AND SURFACE TEMPERATURES WILL BE
CRUCIAL FOR THE LATE WEDNESDAY NIGHT INTO THURSDAY FORECAST AS
TEMPERATURES LOOK TO BE AT OR SLIGHTLY BELOW FREEZING THROUGH MID
MORNING BEFORE WARMING SLIGHTLY THROUGH THE DAY. WILL CONTINUE TO
SHOW HIGH CHANCE OR EVEN LIKELY POPS ACROSS THE AREA STARTING VERY
LATE WEDNESDAY NIGHT AND REMAINING THROUGH THURSDAY.
HOPEFULLY...MODELS WILL CLOSE IN ON THE LOCATION OF THE BEST
PRECIPITATION FOR THIS PERIOD...AS IT APPEARS TO BE A DECENT
OPPORTUNITY FOR FREEZING RAIN ACROSS THE U.P.. WILL CONTINUE TO
MENTION THIS THREAT IN THE HWO AND WITH THE INCREASING CONFIDENCE
START TO PROVIDE A LITTLE MORE DETAIL.
THE UPPER LOW WILL CONTINUE TO LIFT NORTHEAST TOWARDS THE AREA
THURSDAY NIGHT AND THROUGH THE UPPER GREAT LAKES
FRIDAY/SATURDAY...BUT MODELS STILL DIFFERING ON THE DETAILS. WHILE
THE CONSISTENCY IS LACKING...THE LATEST TRENDS WITH THE 00Z MODELS
IS FOR A QUICKER LIFT TO THE NORTHEAST OF THE UPPER LOW/TROUGH WHICH
WOULD ALLOW IT TO PHASE WITH THE NORTHERN STREAM. THE 00Z ECMWF MADE
A SIGNIFICANT JUMP TOWARDS THE FASTER SOLUTION SEEN IN THE PREVIOUS
GFS RUNS. THAT IS A SIGNIFICANT DEPARTURE FROM THE 12Z ECMWF/GEM
ENSEMBLE MEANS...SO IT WILL BE INTERESTING IF THAT TREND CONTINUES.
OVERALL...FELT A GENERAL CONSENSUS OF THE MODELS WAS REASONABLE FOR
THE THURSDAY NIGHT INTO FRIDAY NIGHT PERIOD...WHICH HAS THE NEXT
WAVE OF PRECIPITATION MOVING NORTHEAST ACROSS THE CWA AFTER MIDNIGHT
THURSDAY NIGHT AND CONTINUING INTO FRIDAY. WITH THE FASTER AND
FARTHER SOUTHEAST TRACK OF THE SURFACE LOW...A TRANSITION FROM RAIN
OR FREEZING RAIN WILL OCCUR OVER THE WESTERN HALF OF UPPER MICHIGAN
ON FRIDAY. THERE COULD BE SOME MEASURABLE ACCUMULATIONS OVER THE
WEST...BUT IT IS STILL WAY TO FAR OUT AND UNCERTAIN TO HAVE AN
INDICATION ON AMOUNTS.
DEPENDING ON HOW QUICKLY THE SYSTEM MOVES THROUGH THE
AREA...SATURDAY COULD SEE SOME LINGERING PRECIPITATION.
OTHERWISE...IT LOOKS LIKE MUCH OF THE WEEKEND WILL BE DRY. ANOTHER
STRONG SYSTEM DROPS SOUTHEAST OUT OF THE GULF OF ALASKA ON SATURDAY
MORNING AND INTO THE NORTHERN PLAINS ON SUNDAY NIGHT. THAT SETS THE
STAGE FOR AN ACTIVE START TO THE NEXT WORK WEEK (RAINY AND POSSIBLY
SOME THUNDERSTORMS FOR MONDAY BEFORE CHANGING TO SNOW ON THE
BACKSIDE FOR TUESDAY THE 14TH).
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 743 AM EDT MON APR 6 2015
SAW AND IWD ARE CURRENTLY NEAR THE NRN EDGE OF SN SHIELD ASSOCIATED
WITH WARM FNT TO THE S. THE LLVL ENE FLOW TO THE N OF THE FNT
PRESENTS AN UPSLOPE COMPONENT INTO SAW AND WL ALLOW SOME -SN AND
MVFR CONDITIONS TO PERSIST THERE THRU THE MRNG. SINCE THE LLVL WIND
IS DOWNSLOPING INTO IWD...THE BULK OF THE SN AND LOWER CIGS SHOULD
HOLD JUST TO THE S OF THAT LOCATION. CMX IS SITUATED DEEPER INTO THE
DRY AIR...SO VFR CONDITIONS WL BE THE RULE THERE THRU THE DAY.
EXPECTED SURGE OF DRIER AIR LATER TDAY/TNGT WL RESULT IN VFR
CONDITIONS AT ALL THE SITES TNGT UNDER SOME MID CLDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT MON APR 6 2015
WITH LAKE SUPERIOR SITUATED BETWEEN A HIGH IN SOUTHERN CANADA AND A
WARM FRONT OVER THE LOWER GREAT LAKES...EXPECT EAST TO NORTHEAST
WINDS TO PERSIST THROUGH WEDNESDAY NIGHT. MOST OF THE TIME...WINDS
WILL BE BELOW 25KTS...BUT FUNNELING DOWN THE WESTERN THIRD OF
LAKE SUPERIOR ON TUESDAY COULD PRODUCE GUSTS TO 30KTS. A LOW
PRESSURE SYSTEM LIFTING NORTHEAST OUT OF THE CENTRAL PLAINS WILL
MOVE THROUGH THE GREAT LAKES REGION ON FRIDAY THERE COULD BE
NORTH-NORTHEAST GUSTS TO 25 KNOTS AS IT MOVES THROUGH ON FRIDAY
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING
FOR MIZ010>013.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
655 AM EDT MON APR 6 2015
.UPDATE...
ISSUED AT 654 AM EDT MON APR 6 2015
BASED ON PERSISTENCE OF HIER RADAR ECHOES/LOWER VSBY ALONG THE WI
BORDER WITHIN RATHER NARROW FGEN BAND AS WELL AS SOME HEAVIER SN
REPORTS JUST S OF THE WI BORDER THAT ARE MORE IN LINE WITH THE HIER
QPF SHOWN BY THE VARIOUS HI RES MODELS...OPTED TO ISSUE ADVY FOR
IRON...DICKINSON AND DELTA COUNTIES FOR AS MUCH AS 4 TO PERHAPS 5
INCHES. STILL LOOKS LIKE THE STEADIER SN WL DIMINSH BY MID MRNG WITH
PASSAGE OF DISTURBANCE TO THE E.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 437 AM EDT MON APR 6 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A CONFLUENT W FLOW
OVER THE UPR LKS BTWN ARCTIC BRANCH CLOSED LO OVER NRN QUEBEC AND
POLAR/SUBTROPICAL BRANCH UPR RDG IN THE NRN PLAINS. THERE IS A SHARP
H85 WARM FNT ORIENTED W-E ACRS THE UPR MIDWEST SEPARATING THE VERY
COLD AIR OVER ONTARIO...WHERE THE 00Z H85 TEMP WAS -16C AT YPL FROM
MUCH WARMER AIR IN THE CENTRAL CONUS...WHERE THE 00Z H85 TEMP WAS 9C
AT OMAHA. A RATHER NARROW W-E BAND OF SN IN THE GENERAL ISENTROPIC
ASCENT N OF THE WARM FNT AND UNDER SOME UPR DVGC IN RRQ OF 120KT H3
JET MAX IN SE CANADA IS ORIENTED FM CENTRAL MN ACRS NRN WI INTO MNM
COUNTY EARLY THIS MRNG ALONG AXIS OF SHARPEST FGEN BEST DEFINED IN
THE H7-6 LYR. BUT OVERALL DRYNESS OF THE LLVL AIRMASS IN THE AREA...
ESPECIALLY IN AREAS TO THE N CLOSER TO SFC HI PRES ORIENTED FM SRN
MANITOBA ACRS FAR NRN LK SUP AND INTO SW QUEBEC...IS LIMITING THE
COVERAGE OF THE PCPN TO A FAIRLY NARROW BAND. LATEST RADAR IMAGERY
INDICATES INCRSG REFLECTIVITIES IN MN AHEAD OF A SHRTWV MOVING E
THRU THE NRN PLAINS AS INDICATED ON WV IMAGERY.
MAIN FCST CONCERNS IN THE SHORT TERM WL FOCUS ON POPS/SN AMOUNTS
OVER MAINLY THE SRN TIER COUNTIES THIS MRNG ASSOCIATED WITH NARROW
BAND OF SN AND NEEDED HEADLINES.
TODAY...SHRTWV/AREA OF DEEP LYR QVECTOR CNVGC NOW BRINGING
ENHANCEMENT TO THE PCPN OVER MN AND NRN WI IS FCST TO SLIDE E EARLY
THIS MRNG...BRINGING A PERIOD OF MORE FOCUSED DYNAMIC SUPPORT TO THE
CWA MAINLY TRHU MID MRNG. RECENT RADAR TRENDS SHOWING SOME
INTENSIFICATION OF THE ECHOES IN NW WI SUPPORT SOME OF THE RECENT
HIER RES MODEL FCSTS LIKE THE 00Z NAM OF THE HIER QPF UP TO ABOUT
0.30-0.35 INCH DRIFTING FARTHER TO THE N INTO THE WI BORDER
COUNTIES...A QPF CONSISTENT WITH THE 3 G/KG SPECIFIC HUMIDITY
PRESENT ARND H7. RATHER HI...NARROW DGZ SHOWN ON FCST SDNGS WL NOT
SUPPORT SN/WATER RATIO MUCH HIER THAN 10:1 IN THIS AREA. CONSIDERING
ADDING THESE COUNTIES TO ADVY...BUT POTENTIAL IMPACT OF LLVL DRY AIR
TO THE N THAT MIGHT LOWER THE QPF TO WHAT IS SHOWN ON SOME OF THE
OTHER HI RES MODELS LIKE THE HRRR INDICATE AN SPS FOR UP TO ABOUT 3
INCHES NEAR THE BORDER IN IRON AND DICKINSON COUNTIES AS WELL
AS DELTA COUNTY MIGHT BE A BETTER STATEGY. WL MAINTAIN THE WINTER WX
ADVY FOR MENOMINEE COUNTY. SINCE FCST SDNGS DO NOT SHOW AN ELEVATED
WARM LYR THAT FEATURES TEMPS ABOVE 0C...REMOVED THE MENTION OF MIXED
PCPN THIS MRNG. THE EXTENT OF THE DRY AIR TO THE N WL LIKELY RESULT
IN A SHARPER NRN EDGE OF THE MORE SGNFT PCPN THAN IS SHOWN BY THE
MODELS. ARRIVAL OF QVECTOR DVGC/SUBSIDENCE IN THE WAKE OF THE
PASSING SHRTWV BY LATE MRNG WL CAUSE THE SN BAND TO DIMINISH...WITH
LINGERING LGT PCPN OVER THE SCENTRAL TRANSITIONING TO A MIX OF
SN WITH SOME SPRINKLES/LIGHT RA AS TEMPS RISE INTO THE MID/UPR 30S.
ARRIVAL OF SOME DRIER AIR INTO THE NRN TIER COUNTIES THIS AFTN WL
END ANY LINGERING PCPN THERE EVEN AS SOME CLDS LINGER.
TNGT...ALTHOUGH THERE ARE HINTS ANOTHER SHRTWV/SOME DYNAMIC SUPPORT
WL PUSH INTO THE AREA FM THE W IN THE ZONAL FLOW ALOFT...THE
CONTINUED ARRIVAL OF DRIER LLVL AIR SHOULD LIMIT POPS TO THE
SCENTRAL. TENDED TO CUT POPS FM PREVIOUS FCST ESPECIALLY OVER THE
NRN TIER...WITH NO HIER THAN CHC POPS EVEN NEAR THE WI BORDER.
LINGERING CLDS WL LIMIT THE DIURNAL TEMP FALL EVEN WITH THE ARRIVAL
OF LLVL DRIER AIR.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 422 AM EDT MON APR 6 2015
THE LONG TERM FORECAST CONTINUES TO BE A FRUSTRATING EXPERIENCE WHEN
ATTEMPTING TO PIN DOWN THE FINER DETAILS OF THE FORECAST. ESPECIALLY
WITH THE UPPER GREAT LAKES REGION ON THE NORTHERN EDGE OF THE
DISTURBANCES AND HAVING THERMAL PROFILES THAT SUPPORT MIXED
PRECIPITATION AND FREEZING RAIN.
THE START OF THE LONG TERM FORECAST HAS THE UPPER GREAT LAKES REGION
BETWEEN A HIGH MOVING EAST ACROSS ONTARIO AND THE WARM FRONT DRAPED
FROM WEST TO EAST ACROSS THE LOWER GREAT LAKES REGION. WITH THIS
WARM FRONT SLOWLY SINKING SOUTH ON TUESDAY...WOULD EXPECT THE BULK
OF THE PRECIPITATION TO STAY SOUTH OF THE CWA...BUT THE AREA
CONTINUES TO SEE WEAK SHORTWAVE EJECTING OUT OF THE UPPER TROUGH
OVER THE WESTERN CONUS AND THROUGH THE REGION. WITH THE FLUCTUATIONS
IN THE MODELS OVER THE LAST SEVERAL DAYS...WILL OPT TO TREND THE
FORECAST IN THE LATEST DIRECTIONS WITH OUT GETTING TOO SPECIFIC.
THEREFORE FOR TUESDAY...THINK THE DRY AIR (BETWEEN 850-750MB)
ASSOCIATED WITH THE HIGH MOVING THROUGH ONTARIO WILL KEEP THE
NORTHEAST HALF OF THE CWA DRY WHILE THE AREA ALONG THE WISCONSIN
BORDER MAY SEE SOME LIGHT PRECIPITATION ON THE NORTHERN EDGE OF THE
850-700MB WARM AIR ADVECTION INITIALLY IN THE MORNING. ALTHOUGH
THERE ARE SOME HINTS OF THE ICE CRYSTALS CUTTING OUT...OPTED TO KEEP
P-TYPE AS SNOW DUE THE THE AMOUNT OF DRYING OCCURRING IN THE
MORNING. ALTHOUGH THAT DRY AIR IS MOVING IN...THERE SHOULD BE ENOUGH
FORCING/MOISTURE WITH THE SOUTHWESTERLY FLOW AROUND 700-600MB TO
SUPPORT CLOUDS OVER THE SOUTHWEST 2/3RDS OF THE CWA.
AS THE SURFACE LOW THAT IS CURRENTLY IN THE LEE OF THE CENTRAL
ROCKIES IS SHIFTING EAST THROUGH THE CENTRAL PLAINS...ANOTHER
STRONGER SHORTWAVE LIFTS EAST-NORTHEAST THROUGH THE GREAT LAKES
REGION TUESDAY NIGHT. AT THIS STAGE...THINK THE HEAVIEST
PRECIPITATION WILL STAY TO THE SOUTH-SOUTHEAST OF THE AREA (TRACKING
THROUGH NORTHEAST WISCONSIN AND INTO NORTHERN LOWER MICHIGAN). BUT
THERE SHOULD STILL BE ENOUGH SUPPORT FOR CHANCES OVER THE SOUTH
CENTRAL AND SLIGHT CHANCES FOR MUCH OF THE REST OF THE U.P. LOOKING
AT THE FORECAST SOUNDINGS...EXPECT MUCH OF THIS PRECIP TO FALL AS
SNOW...BUT THERE MAY BE ENOUGH MID LEVEL WARMING OVER SOUTHERN
MENOMINEE COUNTY TO PARTIALLY MELT THE SNOWFLAKES...LEADING TO SOME
SLEET OR MAYBE EVEN FREEZING RAIN. THAT WAVE QUICKLY DEPARTS LATE
TUESDAY NIGHT INTO WEDNESDAY MORNING...SO WOULD EXPECT A DRYING
TREND AS THE DEEPER MOISTURE DEPARTS AND A HIGH PRESSURE RIDGE (FROM
THE HIGH TO THE NORTHEAST OF JAMES BAY) SWINGS EAST ACROSS THE CWA.
THAT WILL MAINTAIN THE DRY CONDITIONS THROUGH AT LEAST WEDNESDAY
EVENING.
AS THE UPPER LOW LIFTS INTO THE CENTRAL ROCKIES ON WEDNESDAY
NIGHT...THE NEXT WAVE WILL EJECT TOWARDS THE REGION UNDER THE
SOUTHWESTERLY FLOW ALOFT. IN ADDITION TO THE SHORTWAVE...WARM AIR
WILL SURGE NORTH OVER THE REGION...WITH 850-800MB TEMPS WARMING
ABOVE 5C. THUS...ANY PRECIPITATION THAT FALLS THROUGH THIS WARM
LAYER WILL MELT AND THE P-TYPE WILL DEPEND ON THE NEAR SURFACE
TEMPERATURES. WITH THE EXISTING COLD AIR FROM THE DEPARTING
HIGH...WOULD EXPECT PRIMARILY FREEZING RAIN FOR THE START OF THE
EVENT (LOWEST 2KFT ARE BELOW FREEZING)...AS IT DOESN/T LOOK LIKE
THERE WILL BE ENOUGH COLD AIR NEAR THE SURFACE FOR SLEET. THE
ARRIVAL TIME OF THE PRECIPITATION AND SURFACE TEMPERATURES WILL BE
CRUCIAL FOR THE LATE WEDNESDAY NIGHT INTO THURSDAY FORECAST AS
TEMPERATURES LOOK TO BE AT OR SLIGHTLY BELOW FREEZING THROUGH MID
MORNING BEFORE WARMING SLIGHTLY THROUGH THE DAY. WILL CONTINUE TO
SHOW HIGH CHANCE OR EVEN LIKELY POPS ACROSS THE AREA STARTING VERY
LATE WEDNESDAY NIGHT AND REMAINING THROUGH THURSDAY.
HOPEFULLY...MODELS WILL CLOSE IN ON THE LOCATION OF THE BEST
PRECIPITATION FOR THIS PERIOD...AS IT APPEARS TO BE A DECENT
OPPORTUNITY FOR FREEZING RAIN ACROSS THE U.P.. WILL CONTINUE TO
MENTION THIS THREAT IN THE HWO AND WITH THE INCREASING CONFIDENCE
START TO PROVIDE A LITTLE MORE DETAIL.
THE UPPER LOW WILL CONTINUE TO LIFT NORTHEAST TOWARDS THE AREA
THURSDAY NIGHT AND THROUGH THE UPPER GREAT LAKES
FRIDAY/SATURDAY...BUT MODELS STILL DIFFERING ON THE DETAILS. WHILE
THE CONSISTENCY IS LACKING...THE LATEST TRENDS WITH THE 00Z MODELS
IS FOR A QUICKER LIFT TO THE NORTHEAST OF THE UPPER LOW/TROUGH WHICH
WOULD ALLOW IT TO PHASE WITH THE NORTHERN STREAM. THE 00Z ECMWF MADE
A SIGNIFICANT JUMP TOWARDS THE FASTER SOLUTION SEEN IN THE PREVIOUS
GFS RUNS. THAT IS A SIGNIFICANT DEPARTURE FROM THE 12Z ECMWF/GEM
ENSEMBLE MEANS...SO IT WILL BE INTERESTING IF THAT TREND CONTINUES.
OVERALL...FELT A GENERAL CONSENSUS OF THE MODELS WAS REASONABLE FOR
THE THURSDAY NIGHT INTO FRIDAY NIGHT PERIOD...WHICH HAS THE NEXT
WAVE OF PRECIPITATION MOVING NORTHEAST ACROSS THE CWA AFTER MIDNIGHT
THURSDAY NIGHT AND CONTINUING INTO FRIDAY. WITH THE FASTER AND
FARTHER SOUTHEAST TRACK OF THE SURFACE LOW...A TRANSITION FROM RAIN
OR FREEZING RAIN WILL OCCUR OVER THE WESTERN HALF OF UPPER MICHIGAN
ON FRIDAY. THERE COULD BE SOME MEASURABLE ACCUMULATIONS OVER THE
WEST...BUT IT IS STILL WAY TO FAR OUT AND UNCERTAIN TO HAVE AN
INDICATION ON AMOUNTS.
DEPENDING ON HOW QUICKLY THE SYSTEM MOVES THROUGH THE
AREA...SATURDAY COULD SEE SOME LINGERING PRECIPITATION.
OTHERWISE...IT LOOKS LIKE MUCH OF THE WEEKEND WILL BE DRY. ANOTHER
STRONG SYSTEM DROPS SOUTHEAST OUT OF THE GULF OF ALASKA ON SATURDAY
MORNING AND INTO THE NORTHERN PLAINS ON SUNDAY NIGHT. THAT SETS THE
STAGE FOR AN ACTIVE START TO THE NEXT WORK WEEK (RAINY AND POSSIBLY
SOME THUNDERSTORMS FOR MONDAY BEFORE CHANGING TO SNOW ON THE
BACKSIDE FOR TUESDAY THE 14TH).
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 122 AM EDT MON APR 6 2015
AS A WARM FRONT OVER THE LOWER MIDWEST/MID MS VLY REGION MOVES
SLOWLY NORTHWARD LATE TONIGHT SOME LIGHT SNOW AND LOWER CIGS WL
BEGIN TO SPREAD INTO UPPER MI...HOWEVER THE DRY NE SFC WIND WILL
KEEP THE HEAVIEST SNOW CONFINED CLOSER TO IRON MOUNTAIN AND
MENOMINEE. THEREFORE...WILL BRING SOME LIGHT SNOW TO IWD AND SAW
OVERNIGHT ALONG WITH LOW END MVFR OR IFR CIGS. DUE TO CMX BEING
FARTHEST FROM THE MOISTURE AND WARM FRONT...EXPECT THAT SITE TO
REMAIN VFR OR HIGH END MVFR THROUGH THE PERIOD WITH ONLY FLURRIES OR
LIGHT SNOW SHOWERS. EXPECT GRADUALLY IMPROVEMENT IN CONDITIONS
THROUGH MON AFTERNOON AND EVENING AS HIGH PRES RDG BEGINS TO BUILD
BACK IN FROM NORTH OF LAKE SUPERIOR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT MON APR 6 2015
WITH LAKE SUPERIOR SITUATED BETWEEN A HIGH IN SOUTHERN CANADA AND A
WARM FRONT OVER THE LOWER GREAT LAKES...EXPECT EAST TO NORTHEAST
WINDS TO PERSIST THROUGH WEDNESDAY NIGHT. MOST OF THE TIME...WINDS
WILL BE BELOW 25KTS...BUT FUNNELING DOWN THE WESTERN THIRD OF
LAKE SUPERIOR ON TUESDAY COULD PRODUCE GUSTS TO 30KTS. A LOW
PRESSURE SYSTEM LIFTING NORTHEAST OUT OF THE CENTRAL PLAINS WILL
MOVE THROUGH THE GREAT LAKES REGION ON FRIDAY THERE COULD BE
NORTH-NORTHEAST GUSTS TO 25 KNOTS AS IT MOVES THROUGH ON FRIDAY
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING
FOR MIZ010>013.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...KC
LONG TERM...SRF
AVIATION...VOSS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
438 AM EDT MON APR 6 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 437 AM EDT MON APR 6 2015
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A CONFLUENT W FLOW
OVER THE UPR LKS BTWN ARCTIC BRANCH CLOSED LO OVER NRN QUEBEC AND
POLAR/SUBTROPICAL BRANCH UPR RDG IN THE NRN PLAINS. THERE IS A SHARP
H85 WARM FNT ORIENTED W-E ACRS THE UPR MIDWEST SEPARATING THE VERY
COLD AIR OVER ONTARIO...WHERE THE 00Z H85 TEMP WAS -16C AT YPL FROM
MUCH WARMER AIR IN THE CENTRAL CONUS...WHERE THE 00Z H85 TEMP WAS 9C
AT OMAHA. A RATHER NARROW W-E BAND OF SN IN THE GENERAL ISENTROPIC
ASCENT N OF THE WARM FNT AND UNDER SOME UPR DVGC IN RRQ OF 120KT H3
JET MAX IN SE CANADA IS ORIENTED FM CENTRAL MN ACRS NRN WI INTO MNM
COUNTY EARLY THIS MRNG ALONG AXIS OF SHARPEST FGEN BEST DEFINED IN
THE H7-6 LYR. BUT OVERALL DRYNESS OF THE LLVL AIRMASS IN THE AREA...
ESPECIALLY IN AREAS TO THE N CLOSER TO SFC HI PRES ORIENTED FM SRN
MANITOBA ACRS FAR NRN LK SUP AND INTO SW QUEBEC...IS LIMITING THE
COVERAGE OF THE PCPN TO A FAIRLY NARROW BAND. LATEST RADAR IMAGERY
INDICATES INCRSG REFLECTIVITIES IN MN AHEAD OF A SHRTWV MOVING E
THRU THE NRN PLAINS AS INDICATED ON WV IMAGERY.
MAIN FCST CONCERNS IN THE SHORT TERM WL FOCUS ON POPS/SN AMOUNTS
OVER MAINLY THE SRN TIER COUNTIES THIS MRNG ASSOCIATED WITH NARROW
BAND OF SN AND NEEDED HEADLINES.
TODAY...SHRTWV/AREA OF DEEP LYR QVECTOR CNVGC NOW BRINGING
ENHANCEMENT TO THE PCPN OVER MN AND NRN WI IS FCST TO SLIDE E EARLY
THIS MRNG...BRINGING A PERIOD OF MORE FOCUSED DYNAMIC SUPPORT TO THE
CWA MAINLY TRHU MID MRNG. RECENT RADAR TRENDS SHOWING SOME
INTENSIFICATION OF THE ECHOES IN NW WI SUPPORT SOME OF THE RECENT
HIER RES MODEL FCSTS LIKE THE 00Z NAM OF THE HIER QPF UP TO ABOUT
0.30-0.35 INCH DRIFTING FARTHER TO THE N INTO THE WI BORDER
COUNTIES...A QPF CONSISTENT WITH THE 3 G/KG SPECIFIC HUMIDITY
PRESENT ARND H7. RATHER HI...NARROW DGZ SHOWN ON FCST SDNGS WL NOT
SUPPORT SN/WATER RATIO MUCH HIER THAN 10:1 IN THIS AREA. CONSIDERING
ADDING THESE COUNTIES TO ADVY...BUT POTENTIAL IMPACT OF LLVL DRY AIR
TO THE N THAT MIGHT LOWER THE QPF TO WHAT IS SHOWN ON SOME OF THE
OTHER HI RES MODELS LIKE THE HRRR INDICATE AN SPS FOR UP TO ABOUT 3
INCHES NEAR THE BORDER IN IRON AND DICKINSON COUNTIES AS WELL
AS DELTA COUNTY MIGHT BE A BETTER STATEGY. WL MAINTAIN THE WINTER WX
ADVY FOR MENOMINEE COUNTY. SINCE FCST SDNGS DO NOT SHOW AN ELEVATED
WARM LYR THAT FEATURES TEMPS ABOVE 0C...REMOVED THE MENTION OF MIXED
PCPN THIS MRNG. THE EXTENT OF THE DRY AIR TO THE N WL LIKELY RESULT
IN A SHARPER NRN EDGE OF THE MORE SGNFT PCPN THAN IS SHOWN BY THE
MODELS. ARRIVAL OF QVECTOR DVGC/SUBSIDENCE IN THE WAKE OF THE
PASSING SHRTWV BY LATE MRNG WL CAUSE THE SN BAND TO DIMINISH...WITH
LINGERING LGT PCPN OVER THE SCENTRAL TRANSITIONING TO A MIX OF
SN WITH SOME SPRINKLES/LIGHT RA AS TEMPS RISE INTO THE MID/UPR 30S.
ARRIVAL OF SOME DRIER AIR INTO THE NRN TIER COUNTIES THIS AFTN WL
END ANY LINGERING PCPN THERE EVEN AS SOME CLDS LINGER.
TNGT...ALTHOUGH THERE ARE HINTS ANOTHER SHRTWV/SOME DYNAMIC SUPPORT
WL PUSH INTO THE AREA FM THE W IN THE ZONAL FLOW ALOFT...THE
CONTINUED ARRIVAL OF DRIER LLVL AIR SHOULD LIMIT POPS TO THE
SCENTRAL. TENDED TO CUT POPS FM PREVIOUS FCST ESPECIALLY OVER THE
NRN TIER...WITH NO HIER THAN CHC POPS EVEN NEAR THE WI BORDER.
LINGERING CLDS WL LIMIT THE DIURNAL TEMP FALL EVEN WITH THE ARRIVAL
OF LLVL DRIER AIR.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 422 AM EDT MON APR 6 2015
THE LONG TERM FORECAST CONTINUES TO BE A FRUSTRATING EXPERIENCE WHEN
ATTEMPTING TO PIN DOWN THE FINER DETAILS OF THE FORECAST. ESPECIALLY
WITH THE UPPER GREAT LAKES REGION ON THE NORTHERN EDGE OF THE
DISTURBANCES AND HAVING THERMAL PROFILES THAT SUPPORT MIXED
PRECIPITATION AND FREEZING RAIN.
THE START OF THE LONG TERM FORECAST HAS THE UPPER GREAT LAKES REGION
BETWEEN A HIGH MOVING EAST ACROSS ONTARIO AND THE WARM FRONT DRAPED
FROM WEST TO EAST ACROSS THE LOWER GREAT LAKES REGION. WITH THIS
WARM FRONT SLOWLY SINKING SOUTH ON TUESDAY...WOULD EXPECT THE BULK
OF THE PRECIPITATION TO STAY SOUTH OF THE CWA...BUT THE AREA
CONTINUES TO SEE WEAK SHORTWAVE EJECTING OUT OF THE UPPER TROUGH
OVER THE WESTERN CONUS AND THROUGH THE REGION. WITH THE FLUCTUATIONS
IN THE MODELS OVER THE LAST SEVERAL DAYS...WILL OPT TO TREND THE
FORECAST IN THE LATEST DIRECTIONS WITH OUT GETTING TOO SPECIFIC.
THEREFORE FOR TUESDAY...THINK THE DRY AIR (BETWEEN 850-750MB)
ASSOCIATED WITH THE HIGH MOVING THROUGH ONTARIO WILL KEEP THE
NORTHEAST HALF OF THE CWA DRY WHILE THE AREA ALONG THE WISCONSIN
BORDER MAY SEE SOME LIGHT PRECIPITATION ON THE NORTHERN EDGE OF THE
850-700MB WARM AIR ADVECTION INITIALLY IN THE MORNING. ALTHOUGH
THERE ARE SOME HINTS OF THE ICE CRYSTALS CUTTING OUT...OPTED TO KEEP
P-TYPE AS SNOW DUE THE THE AMOUNT OF DRYING OCCURRING IN THE
MORNING. ALTHOUGH THAT DRY AIR IS MOVING IN...THERE SHOULD BE ENOUGH
FORCING/MOISTURE WITH THE SOUTHWESTERLY FLOW AROUND 700-600MB TO
SUPPORT CLOUDS OVER THE SOUTHWEST 2/3RDS OF THE CWA.
AS THE SURFACE LOW THAT IS CURRENTLY IN THE LEE OF THE CENTRAL
ROCKIES IS SHIFTING EAST THROUGH THE CENTRAL PLAINS...ANOTHER
STRONGER SHORTWAVE LIFTS EAST-NORTHEAST THROUGH THE GREAT LAKES
REGION TUESDAY NIGHT. AT THIS STAGE...THINK THE HEAVIEST
PRECIPITATION WILL STAY TO THE SOUTH-SOUTHEAST OF THE AREA (TRACKING
THROUGH NORTHEAST WISCONSIN AND INTO NORTHERN LOWER MICHIGAN). BUT
THERE SHOULD STILL BE ENOUGH SUPPORT FOR CHANCES OVER THE SOUTH
CENTRAL AND SLIGHT CHANCES FOR MUCH OF THE REST OF THE U.P. LOOKING
AT THE FORECAST SOUNDINGS...EXPECT MUCH OF THIS PRECIP TO FALL AS
SNOW...BUT THERE MAY BE ENOUGH MID LEVEL WARMING OVER SOUTHERN
MENOMINEE COUNTY TO PARTIALLY MELT THE SNOWFLAKES...LEADING TO SOME
SLEET OR MAYBE EVEN FREEZING RAIN. THAT WAVE QUICKLY DEPARTS LATE
TUESDAY NIGHT INTO WEDNESDAY MORNING...SO WOULD EXPECT A DRYING
TREND AS THE DEEPER MOISTURE DEPARTS AND A HIGH PRESSURE RIDGE (FROM
THE HIGH TO THE NORTHEAST OF JAMES BAY) SWINGS EAST ACROSS THE CWA.
THAT WILL MAINTAIN THE DRY CONDITIONS THROUGH AT LEAST WEDNESDAY
EVENING.
AS THE UPPER LOW LIFTS INTO THE CENTRAL ROCKIES ON WEDNESDAY
NIGHT...THE NEXT WAVE WILL EJECT TOWARDS THE REGION UNDER THE
SOUTHWESTERLY FLOW ALOFT. IN ADDITION TO THE SHORTWAVE...WARM AIR
WILL SURGE NORTH OVER THE REGION...WITH 850-800MB TEMPS WARMING
ABOVE 5C. THUS...ANY PRECIPITATION THAT FALLS THROUGH THIS WARM
LAYER WILL MELT AND THE P-TYPE WILL DEPEND ON THE NEAR SURFACE
TEMPERATURES. WITH THE EXISTING COLD AIR FROM THE DEPARTING
HIGH...WOULD EXPECT PRIMARILY FREEZING RAIN FOR THE START OF THE
EVENT (LOWEST 2KFT ARE BELOW FREEZING)...AS IT DOESN/T LOOK LIKE
THERE WILL BE ENOUGH COLD AIR NEAR THE SURFACE FOR SLEET. THE
ARRIVAL TIME OF THE PRECIPITATION AND SURFACE TEMPERATURES WILL BE
CRUCIAL FOR THE LATE WEDNESDAY NIGHT INTO THURSDAY FORECAST AS
TEMPERATURES LOOK TO BE AT OR SLIGHTLY BELOW FREEZING THROUGH MID
MORNING BEFORE WARMING SLIGHTLY THROUGH THE DAY. WILL CONTINUE TO
SHOW HIGH CHANCE OR EVEN LIKELY POPS ACROSS THE AREA STARTING VERY
LATE WEDNESDAY NIGHT AND REMAINING THROUGH THURSDAY.
HOPEFULLY...MODELS WILL CLOSE IN ON THE LOCATION OF THE BEST
PRECIPITATION FOR THIS PERIOD...AS IT APPEARS TO BE A DECENT
OPPORTUNITY FOR FREEZING RAIN ACROSS THE U.P.. WILL CONTINUE TO
MENTION THIS THREAT IN THE HWO AND WITH THE INCREASING CONFIDENCE
START TO PROVIDE A LITTLE MORE DETAIL.
THE UPPER LOW WILL CONTINUE TO LIFT NORTHEAST TOWARDS THE AREA
THURSDAY NIGHT AND THROUGH THE UPPER GREAT LAKES
FRIDAY/SATURDAY...BUT MODELS STILL DIFFERING ON THE DETAILS. WHILE
THE CONSISTENCY IS LACKING...THE LATEST TRENDS WITH THE 00Z MODELS
IS FOR A QUICKER LIFT TO THE NORTHEAST OF THE UPPER LOW/TROUGH WHICH
WOULD ALLOW IT TO PHASE WITH THE NORTHERN STREAM. THE 00Z ECMWF MADE
A SIGNIFICANT JUMP TOWARDS THE FASTER SOLUTION SEEN IN THE PREVIOUS
GFS RUNS. THAT IS A SIGNIFICANT DEPARTURE FROM THE 12Z ECMWF/GEM
ENSEMBLE MEANS...SO IT WILL BE INTERESTING IF THAT TREND CONTINUES.
OVERALL...FELT A GENERAL CONSENSUS OF THE MODELS WAS REASONABLE FOR
THE THURSDAY NIGHT INTO FRIDAY NIGHT PERIOD...WHICH HAS THE NEXT
WAVE OF PRECIPITATION MOVING NORTHEAST ACROSS THE CWA AFTER MIDNIGHT
THURSDAY NIGHT AND CONTINUING INTO FRIDAY. WITH THE FASTER AND
FARTHER SOUTHEAST TRACK OF THE SURFACE LOW...A TRANSITION FROM RAIN
OR FREEZING RAIN WILL OCCUR OVER THE WESTERN HALF OF UPPER MICHIGAN
ON FRIDAY. THERE COULD BE SOME MEASURABLE ACCUMULATIONS OVER THE
WEST...BUT IT IS STILL WAY TO FAR OUT AND UNCERTAIN TO HAVE AN
INDICATION ON AMOUNTS.
DEPENDING ON HOW QUICKLY THE SYSTEM MOVES THROUGH THE
AREA...SATURDAY COULD SEE SOME LINGERING PRECIPITATION.
OTHERWISE...IT LOOKS LIKE MUCH OF THE WEEKEND WILL BE DRY. ANOTHER
STRONG SYSTEM DROPS SOUTHEAST OUT OF THE GULF OF ALASKA ON SATURDAY
MORNING AND INTO THE NORTHERN PLAINS ON SUNDAY NIGHT. THAT SETS THE
STAGE FOR AN ACTIVE START TO THE NEXT WORK WEEK (RAINY AND POSSIBLY
SOME THUNDERSTORMS FOR MONDAY BEFORE CHANGING TO SNOW ON THE
BACKSIDE FOR TUESDAY THE 14TH).
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 122 AM EDT MON APR 6 2015
AS A WARM FRONT OVER THE LOWER MIDWEST/MID MS VLY REGION MOVES
SLOWLY NORTHWARD LATE TONIGHT SOME LIGHT SNOW AND LOWER CIGS WL
BEGIN TO SPREAD INTO UPPER MI...HOWEVER THE DRY NE SFC WIND WILL
KEEP THE HEAVIEST SNOW CONFINED CLOSER TO IRON MOUNTAIN AND
MENOMINEE. THEREFORE...WILL BRING SOME LIGHT SNOW TO IWD AND SAW
OVERNIGHT ALONG WITH LOW END MVFR OR IFR CIGS. DUE TO CMX BEING
FARTHEST FROM THE MOISTURE AND WARM FRONT...EXPECT THAT SITE TO
REMAIN VFR OR HIGH END MVFR THROUGH THE PERIOD WITH ONLY FLURRIES OR
LIGHT SNOW SHOWERS. EXPECT GRADUALLY IMPROVEMENT IN CONDITIONS
THROUGH MON AFTERNOON AND EVENING AS HIGH PRES RDG BEGINS TO BUILD
BACK IN FROM NORTH OF LAKE SUPERIOR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT MON APR 6 2015
WITH LAKE SUPERIOR SITUATED BETWEEN A HIGH IN SOUTHERN CANADA AND A
WARM FRONT OVER THE LOWER GREAT LAKES...EXPECT EAST TO NORTHEAST
WINDS TO PERSIST THROUGH WEDNESDAY NIGHT. MOST OF THE TIME...WINDS
WILL BE BELOW 25KTS...BUT FUNNELING DOWN THE WESTERN THIRD OF
LAKE SUPERIOR ON TUESDAY COULD PRODUCE GUSTS TO 30KTS. A LOW
PRESSURE SYSTEM LIFTING NORTHEAST OUT OF THE CENTRAL PLAINS WILL
MOVE THROUGH THE GREAT LAKES REGION ON FRIDAY THERE COULD BE
NORTH-NORTHEAST GUSTS TO 25 KNOTS AS IT MOVES THROUGH ON FRIDAY
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 10 AM CDT THIS MORNING FOR MIZ012.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...VOSS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
135 AM EDT MON APR 6 2015
.UPDATE...
ISSUED AT 1039 PM EDT SUN APR 5 2015
MID LEVEL RETURNS HAVE BEEN INCREASING OVER THE PAST FEW HOURS PER
LATEST APX 88D BASE REF LOOP...AND CERTAINLY UPSTREAM RADARS ARE
SHOWING A STEADY INCREASE IN RETURNS AS WELL. NO SIGN OF ANY
PRECIP ACTUALLY REACHING THE GROUND YET PER REGION SURFACE OBS...
BUT STILL EXPECT THIS WILL CHANGE AS WE HEAD INTO THE OVERNIGHT
HOURS. LATEST NAM IS SLIGHTLY FURTHER NORTH WITH THE DEVELOPING
BAND OF PRECIP...WITH A BIT LESS QPF. LATEST HRRR DOESN`T EVEN
PRODUCE ANY QPF UNTIL THE BAND HAS REACHED THE STRAITS AND ERN UPR
MICHIGAN TOWARD DAYBREAK. RADAR TRENDS WOULD SUGGEST THAT WE WILL
SEE AT LEAST SOME PRECIP LATE TONIGHT ACROSS THE NRN TWO-THIRDS
OF OUR CWA ONCE DEEPER MOISTURE AND STRONGER LIFT WITHIN THE DGZ
ARRIVE. SEE NO COMPELLING REASON TO STRAY FROM DEVELOPING
CATEGORICAL POPS OVERNIGHT FOR MUCH OF NRN LWR MICHIGAN....WITH
ONLY AN INCH OR TWO OF SNOW EXPECTED. COULD STILL SEE SOME RAIN
MIX IN ACROSS OUR FAR SRN COUNTIES.
&&
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 331 PM EDT SUN APR 5 2015
HIGH IMPACT WEATHER POTENTIAL: SOME ACCUMULATING SNOW EXPECTED ONCE
AGAIN TONIGHT.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: MID/UPPER LEVEL ANALYSIS
SHOWS MAINTENANCE OF CONFLUENT FLOW PATTERN ACROSS THE NORTHERN
LAKES....FORCING A STALLED SURFACE RESPONSE WITH A STATIONARY FRONT
LINED UP FROM SOUTHERN WISCONSIN THROUGH SOUTHERN LOWER MICHIGAN.
EARLY FGEN DRIVEN SNOW BAND A THING OF THE PAST AS LOW LEVEL JET
VEERED AND WEAKENED. STILL PLENTY OF LOW CLOUDS ALONG AND SOUTH OF M-
55. FURTHER NORTH...A RATHER PLEASANT EASTER WITH PLENTY OF SUNSHINE
AND LIGHT WINDS...ALTHOUGH GOTTA ADMIT TEMPERATURES ARE A TOUCH ON
THE COOL SIDE WITH READINGS MOSTLY IN THE 30S AND LOWER 40S. SOME
CHANGES STARTING TO OCCUR JUST UPSTREAM...WITH NOTED SLOW HEIGHT
RISES BACK ACROSS THE UPPER MISSISSIPPI VALLEY. LOW LEVEL JET WILL
RAMP UP ONCE AGAIN THIS EVENING IN RESPONSE...HELPING DRIVE CURRENT
STATIONARY H8 FRONT NORTHWARD AND SPAWNING ANOTHER ROUND OF FGEN
DRIVEN PRECIP INTO OUR AREA.
PRIMARY FORECAST CONCERNS/CHALLENGES: PLENTY! MAIN FOCUS CENTERED ON
EVOLUTION OF EXPECTED EXPANDING PRECIP BAND (INCLUDING TIMING AND
TYPE THIS PRECIPITATION WILL TAKE) LATER THIS EVENING AND OVERNIGHT.
SNOWFALL AMOUNTS AND HEADLINE CONSIDERATION WILL ALSO NEED
ADDRESSING.
DETAILS: RATHER QUIET CONDITIONS TO START THIS EVENING. CHALLENGES
RAMP-UP CONSIDERABLY HEADING THROUGH THIS EVENING AND OVERNIGHT AS
SAID LOW LEVEL JET RESPONSE AND FGEN INTENSIFY. NOT A TON OF
AVAILABLE MOISTURE...WITH ANALYZED PWAT VALUES LESS THAN HALF AN
INCH EXTENDING DOWN INTO THE CENTRAL PLAINS. THIS SHOULD IMPROVE
SOME WITH INTENSIFYING SOUTHWEST FLOW ON SOUTH SIDE OF FRONTAL
AXIS...WITH CORRIDOR OF HALF INCH PWATS PUSHING INTO THE LAKES
OVERNIGHT. INCREASED AND FOCUSED CONVERGENCE ALONG SLOWLY NORTHWARD
BOWING H8 FRONT SHOULD ENTICE DEVELOPMENT OF PRECIP ALONG AND NORTH
OF ITS AXIS...WHICH SHOULD EXPAND/INTENSIFY/AND SLOWLY MOVE ACROSS
MUCH OF NORTHERN LOWER MICHIGAN LATER TONIGHT INTO THE EARLY MORNING
HOURS. CROSS SECTIONS CONCUR...WITH EXCELLENT SLOPED FGEN SIGNAL AND
FORCED WARM SIDE AGEOSTROPHIC RESPONSE. EVEN SOME HINTS OF REDUCED
INSTABILITY ALOFT (EPV VALUES JUST STRADDLING ZERO)...PLACED NICELY
WITHIN AREA OF MAX OMEGA AND GOOD DEEP LAYER SATURATION. FORCING
LOOKS TO REACH MATURITY IN THE M-72/M-68 CORRIDOR DURING THE EARLY
MORNING. BAND(S) SHOULD REMAIN JUST TRANSIENT ENOUGH TO PREVENT
REALLY SIGNIFICANT ACCUMULATIONS...BUT COULD EASILY SEE SOME AREAS
APPROACH A TENTH TO QUARTER INCH OF LIQUID BY MORNING.
AFTER AN INITIAL RAIN/SNOW MIXTURE THIS EVENING...INTENSIFYING
DYNAMICS/COOLING BOUNDARY LAYER SHOULD RESULT IN A QUICK CHANGEOVER
TO SNOW ALONG AND NORTH OF M-55. WARM NOSE SOUTH OF H8 FRONT PUNCHES
IN THROUGH THE OVERNIGHT SOUTH OF M-72...JUST AS HEAVIEST PRECIP IS
ENDING. WILL CONTINUE THEME OF RAIN/SNOW MIXTURE AS THIS
OCCURS...INTRODUCING SOME FREEZING RAIN POTENTIAL WITH STILL COLD
LOW LEVELS. NOT EXPECTING THIS TO BE A BIG DEAL AS HIGHEST PRECIP
RATES WILL HAVE ENDED BY THE TIME THIS OCCURS.
SNOW TOTALS: LOOKS LIKE A QUICK HITTING INCH OR TWO OF SNOW ACROSS
NORTH CENTRAL LOWER UP TO THE TIP OF THE MITT. LESS AMOUNTS SOUTH
(RAIN/SNOW MIXTURE) AND EASTERN UPPER (LATER START/WEAKER DYNAMICS).
NOT SEEING THE NEED FOR A HEADLINE...BUT WILL KICK AROUND THE IDEA
OF A SPECIAL WEATHER STATEMENT TO RAISE CONCERN FOR SOME SNOW-
COVERED AND SLUSHY ROADS DURING THE MORNING COMMUTE.
&&
.SHORT TERM...(MONDAY THROUGH WEDNESDAY)
ISSUED AT 331 PM EDT SUN APR 5 2015
MAIN CONCERN DURING THIS TIME PERIOD IS PRECIPITATION TYPE AND
TIMING AS NORTHERN MICHIGAN REMAINS IN A ZONAL FLOW WITH A
STATIONARY FRONT OVER SOUTHERN MICHIGAN. 295K ISENTROPIC SURFACE
SHOWS GULF MOISTURE BEING TRANSPORTED NORTHWARD THROUGH 700MB AS FAR
NORTH AS NORTHERN MICHIGAN. FORECAST SOUNDINGS HAVE INDICATED PWATS
THROUGHOUT THE TIME PERIOD OF BETWEEN 0.5 AND 0.75 INCHES. WITH THE
AMPLE MOISTURE AND ADDED LIFT FROM THE DIVERGENT QUADRANT OF THE
RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET
OVERHEAD...PRECIPITATION POTENTIAL EXISTS THROUGH WEDNESDAY EVENING.
AS MENTIONED EARLIER...PRECIPITATION TYPE WILL BE A MAJOR
CONCERN...ESPECIALLY TUESDAY THROUGH WEDNESDAY MORNING AS MODEL
FORECAST SOUNDINGS AGREE WITH FREEZING DRIZZLE/FREEZING RAIN
POSSIBLE. EASTERLY WINDS TRANSPORTING COLDER AIR WRAPPING AROUND A
LARGE HIGH PRESSURE SYSTEM OVER SOUTHEASTERN CANADA MAY COLLIDE WITH
THE AFOREMENTIONED GULF MOISTURE IN THE LOW TO MID LEVELS (700MB AND
BELOW)...WITH THE TOP OF THE SATURATED LAYER FORECAST TO ONLY REACH
TO THE -6C ISOTHERM. AS TEMPERATURES DROP BELOW FREEZING TUESDAY
NIGHT THE POSSIBILITY OF ANY DRIZZLE/RAIN FREEZING ON THE
SIDEWALK/ROAD SURFACES WOULD BECOME A PROBLEM THROUGHOUT THE NIGHT
AND INTO THE MORNING HOURS OF WEDNESDAY. WILL LEAVE THIS OUT OF THE
FORECAST UNTIL CONFIDENCE GETS HIGHER WITH CONSISTENT/FUTURE MODEL
TRENDS. ANY OTHER PRECIPITATION THROUGHOUT THIS PERIOD WILL FALL AS
SNOW OR A SNOW/RAIN MIX DURING THE LATE NIGHT AND EARLY MORNING
HOURS UNTIL IT CHANGES OVER TO ALL RAIN WITH DIURNAL HEATING. ANY
ACCUMULATIONS OF SNOW WILL BE LIGHT...IF ANY...AND WILL MELT QUICKLY
ON ROAD SURFACES AFTER SUNRISE. WINDS WILL BE PERSISTENTLY OUT OF
THE EAST TO EAST-NORTHEAST THROUGHOUT THE PERIOD...WITH TUESDAY
AFTERNOON AND EVENING HAVING THE HIGHEST WINDS GUSTING TO AROUND 25
MPH. HIGHS THROUGHOUT THIS PERIOD WILL BE MID 30S TO LOW 40S WITH
LOWS IN THE MID 20S TO LOW 30S.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 331 PM EDT SUN APR 5 2015
STILL SOME UNCERTAINTY WITH THE TRACK AND TIMING OF THE SYSTEM...BUT
SOME LATE WEEK/WEEKEND PRECIPITATION LOOKS TO BE IN THE CARDS. 500
MB TROUGH CURRENTLY OFF PAC NW COAST WILL BE MOVING INLAND WED/THU.
THE STRENGTH AND SPEED OF THIS IS THE MAIN CAUSE OF UNCERTAINTY...AS
THIS WILL BE PROPAGATING THE LOW OUT OF THE LEE OF THE ROCKIES AND
INTO THE GREAT LAKES. PRECIP WILL START AHEAD OF THE MAIN LOW...AS
THERE WILL BE SOME 500 MB SHORTWAVE IMPULSES PROVIDING UPPER LEVEL
SUPPORT...ALONG WITH A WARM FRONT SETTING UP THROUGH CENTRAL AND
SOUTHERN MICHIGAN ATTENDANT TO THE APPROACHING LOW. THINGS WILL
CLEAR OUT AS HIGH PRESSURE BUILDS INTO THE REGION BEHIND THE
DEPARTING LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 134 AM EDT MON APR 6 2015
PERIODS OF -SN OR MIXED PRECIP AT APN/PLN/TVC...MAINLY THIS
MORNING.
PRECIP WILL CONTINUE TO BE GENERATED AT TIMES...NORTH OF A
STALLED FRONT DOWNSTATE. MOST OF THIS WILL BE NORTH OF MBL...BUT
THE OTHER TAF SITES WILL CONTEND WITH PERIODS OF -SN OR
-SNRA...ESPECIALLY THIS MORNING. IFR CONDITIONS WILL BE SEEN AT
TIMES. TVC/MBL WILL BE LARGELY VFR THIS AFTERNOON/EVENING...WHILE
APN/PLN WILL RIDE THE EDGE OF MVFR/IFR.
EASTERLY WINDS TODAY APN/PLN...LIGHTER/VARIABLE WINDS TVC/MBL.
&&
.MARINE...
ISSUED AT 331 PM EDT SUN APR 5 2015
EAST FLOW WILL INTENSIFY OVERNIGHT...BUT SHOULD REMAIN
BELOW HEADLINE CRITERIA. SAME STORY HEADING THROUGH SUNDAY AND
SUNDAY NIGHT AS A FRONT HOVERS ACROSS THE AREA. NEXT ROUND OF MARINE
HEADLINES LOOKS TO OCCUR ON TUESDAY AS NORTHEAST WINDS STRENGTHEN
WITH LOW PRESSURE PASSING THROUGH THE OHIO VALLEY.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...MLR
NEAR TERM...MSB
SHORT TERM...TJL
LONG TERM...ALM
AVIATION...JAZ
MARINE...MSB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
723 PM CDT TUE APR 7 2015
.UPDATE...
ISSUED AT 715 PM CDT TUE APR 7 2015
UPDATED TO INCLUDE 00Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 330 PM CDT TUE APR 7 2015
CURRENT CONDITIONS SYNOPSIS...
CLUSTER OF SHOWERS AND EMBEDDED THUNDERSTORMS CURRENTLY MOVING
THROUGH THE SOUTHERN PORTION OF THE AREA ALONG THE NORTHERN
PERIPHERY OF THE INSTABILITY... WITH A NOTABLE GRADIENT IN MUCAPE
JUMPING FROM 0 TO 500 J/KG SOUTH OF THE BORDER. DEEP LAYER SHEAR
IS STRONG... AND ONE STORM DID BRIEFLY SHOW SOME MID-LEVEL
ROTATION... AND MANAGED TO PRODUCE MARGINALLY SEVERE HAIL. THE
ACTIVITY SHOULD TRANSLATE EAST AND FOCUS MORE SOUTH AS THE
SHORTWAVE EVIDENT ON WATER VAPOR NEAR THE NEBRASKA/IOWA BORDERS
SHIFTS EAST THROUGH EARLY EVENING.
FORECAST ITEM/S/ OF CONCERN...
CHANCES FOR PCPN... SOME THUNDER... AND PERHAPS SOME MIXED PCPN
INTO TONIGHT... WITH THINGS DRYING OUT WEDNESDAY.
MODEL DISCUSSION/PREFERENCES...
PRIMARILY RELYING ON CAM GUIDANCE... PARTICULARLY HRRR AND HOPWRF
MEMBERS... WHICH HAVE A DECENT HANDLE ON CURRENT CONVECTIVE
ACTIVITY ACROSS THE AREA... BLENDING MORE TOWARD NAM/GFS SOLUTIONS
ON WEDNESDAY.
SENSIBLE WEATHER EXPECTATIONS...
EXPECT SHRA AND EMBEDDED TSRA TO IMPACT THE SOUTHERN PORTION OF
THE AREA INTO PERHAPS THE EARLY EVENING... OTHERWISE WILL SEE
PCPN ON THE NORTH SIDE OF SURFACE LOW MOVE EAST ACROSS THE AREA
THROUGH THE REMAINDER OF THE EVENING. SOME SLEET COULD MIX IN AT
TIMES OVER THE NORTH AND NORTHEAST PORTION OF THE AREA WHERE THE
WARM LAYER IS A BIT LESS DEEP. SHOULD SEE ENOUGH DRYING/SUBSIDENCE
IN THE MID-LEVELS FOR PCPN TO COME TO AN END LATER TONIGHT... WITH
DRY WEATHER OTHER THAN PERHAPS SOME PATCHY DRIZZLE THROUGH MOST OF
WEDNESDAY. SOME SHRA COULD WORK BACK INTO THE SOUTHERN PART OF THE
AREA BY LATER WEDNESDAY AS THE NEXT SHORTWAVE AND SURFACE IMPULSE
ALONG THE BAROCLINIC ZONE WORK INTO THE REGION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 PM CDT TUE APR 7 2015
THE STORM SYSTEM OFF THE COAST OF CALIFORNIA WILL IMPACT OUR
REGION FROM WEDNESDAY NIGHT THRU EARLY FRIDAY MORNING. THE FIRST
PART OF THE STORM HAS THE POTENTIAL OF SVR WX IN THE FAR SE BASED
ON STABILITY PARAMETERS...LOW FREEZING LEVEL AND MID LEVEL LAPSE
RATES. THE BEST POTENTIAL WILL BE THURSDAY AFTERNOON FROM ALBERT
LEA...NORTHEAST TO EAU CLAIRE WISCONSIN. SEE THE LATEST SPC DAY 3
OUTLOOK.
SEVERAL FACTORS NEED TO COME TOGETHER FOR SNOWFALL TO ACCUMULATE
IN OUR CWA. FIRST...THE BEST CHC OF PRECIPITATION AND HIGHER
PRECIPITATION RATES OCCUR BETWEEN 18Z THU TO 06Z FRIDAY. THE SFC
LOW REMAINS IN A FAVORABLE TRACK FOR THE PRECIPITATION TO CHANGE
OVER TO SNOW DURING THE LATE AFTN/EVENING. HOWEVER...THERMAL
PROFILERS REMAINED UNFAVORABLE OF THIS CHANGE OVER IN OUR
CWA...WITH ONLY A SMALL AREA OF THICKNESS VALUES DROPPING TO
CRITICAL LEVELS IN EC MN/WC WI THURSDAY EVENING. THERE REMAINS A
VERY STRONG SIGNAL OF A TROWAL AND DEFORMATION ZONE DEVELOPMENT IN
EC MN/WC WI THURSDAY EVENING. AS WITH PREVIOUS DISCUSSIONS...
THERE IS A POTENTIAL OF HEAVY SNOWFALL IN A SMALL BAND IF ALL THE
WEATHER ELEMENTS COME TOGETHER. IN ADDITION...A CROSS SECTION OF
THE ATMOSPHERE FROM WC MN TO SOUTHERN WI HAS EC MN IN FAVORABLE
AREA OF CONVECTIVE STABILITY INDEX /CSI/ AND SLANTWISE CONVECTIVE.
THEREFORE...IT IS HIGHLY PROBABLE FOR SOMEWHERE IN EASTERN
MN/WESTERN WI TO SEE A HEAVY SNOWFALL EVENT THURSDAY EVENING IF
THIS TYPE OF SCENARIO DEVELOPS.
PAST THURSDAY...A COOL PERIOD WILL OCCUR FROM FRIDAY THRU
SATURDAY BEFORE SOUTHERLY FLOW BEGINS. LATE IN THE WEEKEND AND
INTO NEXT WEEK REMAIN VERY UNSETTLED AS ANOTHER STORM SYSTEM
BEGINS TO DEVELOP ACROSS THE CENTRAL U.S. WITH THIS TYPE OF
PATTERN...TEMPS MAY FLUCTUATE RAPIDLY BASED ON THE AMOUNT CLOUD
COVER AND PRECIPITATION POTENTIAL...BUT AN OVERALL MEAN IS TO
CONTINUE WITH SLIGHTLY BLW NORMAL TEMPS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 715 PM CDT TUE APR 7 2015
RAINFALL HAS SHIFTED OFF TO THE E OF ALL WFO MPX TERMINALS...
LEAVING INCOMING LOW CLOUDS IN THE WAKE OF THE RAIN SHIELD. WITH
LLVL E WINDS IN THE 5-10KT RANGE OVERNIGHT THRU MIDDAY TMRW... LOW
CEILINGS WILL PREVAIL INCLUDING A PERIOD OVERNIGHT THRU LATE TMRW
MRNG OF IFR CEILINGS. NOT LOOKING FOR MUCH IN THE WAY OF VSBY
RESTRICTION DUE TO WIND SPEEDS REMAINING UP BUT SHOULD SPEEDS DROP
BELOW 5 KT...VSBY MAY EASILY BE LOWER THAN WHAT IS CURRENTLY
ADVERTISED. SLOW IMPROVEMENT EXPECTED FOR LATE TMRW WITH NO
FURTHER PRECIP EXPECTED UNTIL WED EVE.
KMSP...CEILINGS WILL STEADILY LOWER OVER MSP...WITH CEILINGS
FALLING BELOW 1700 FT BY ARND MIDNIGHT AND REMAINING THERE THRU
THE MORNING PUSH. NOT LOOKING FOR ANY VSBY LOWER THAN VFR...BUT A
FEW PRE-DAWN OBS IN THE MVFR RANGE CANNOT BE RULED OUT /THOUGH
CEILINGS WOULD LIKELY BE IFR AT THAT POINT ANYWAY/. CONDS TO
SLOWLY IMPROVE LATE DAY WITH WINDS CONTINUING IN THE 070-090
DIRECTIONAL RANGE BUT SPEEDS INCRG TO ARND 10 KT LATE. PRECIP TO
RETURN TMRW EVE AND LIKELY TO LAST MUCH OF THE OVERNIGHT PERIOD.
/OUTLOOK FOR KMSP/
THU...MVFR POSSIBLY IFR. RA LIKELY. WINDS N 15-25 KTS.
FRI...VFR. WINDS NW 10-15 KTS.
SAT...VFR. WINDS S 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...JPC
SHORT TERM...
LONG TERM...JLT
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS DULUTH MN
1242 AM CDT MON APR 6 2015
.UPDATE...
ISSUED AT 1242 AM CDT MON APR 6 2015
UPDATED AVIATION SECTION BELOW.
UPDATE ISSUED AT 646 PM CDT SUN APR 5 2015
DELAYED THE ONSET OF THE PCPN A LITTLE BIT AS DRY AIR FROM LAKE
SUPERIOR CONTINUES TO ADVECT INTO THE AREA. PCPN WILL START AS
RAIN OVER THE SOUTHERN TIER OF THE FORECAST AREA BEFORE MIXING
WITH AND THEN CHANGING TO ALL SNOW. REST OF THE FORECAST ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 406 PM CDT SUN APR 5 2015
MAIN CHALLENGE IN THE SHORT TERM WILL BE THE POTENTIAL FOR A QUICK
HIT OF ACCUMULATING SNOW ACROSS PORTIONS OF THE NORTHLAND TONIGHT.
ADDITIONAL RAIN AND SNOW SHOWERS ARE POSSIBLE MONDAY AFTERNOON.
A WINTER WEATHER ADVISORY IS IN EFFECT FOR AREAS OF EAST CENTRAL
MINNESOTA AND NORTHWEST WISCONSIN FROM MIDNIGHT TONIGHT THROUGH 10
AM MONDAY. AREAS IN THE ADVISORY WILL LIKELY SEE 2 TO 4
INCHES...WITH ISOLATED HIGHER AMOUNTS NOT OUT OF THE QUESTION.
AN AREA OF LOW PRESSURE AT THE SURFACE CONTINUES TO DEVELOP OVER
THE CENTRAL PLAINS THIS AFTERNOON WITH A WARM FRONT EXTENDING TO
THE EAST INTO SRN MN. SOUTH OF THE FRONT THERE IS VERY STRONG WAA
IN THE MID LEVELS...ACROSS A DEEP LAYER...WHICH IS PRODUCING A
STRENGTHENING BAND OF F-GEN JUST SOUTH OF THE TWIN CITIES. AS
EVIDENT ON THE LATEST RAP ANALYSIS. CLOUD COVER AND RADAR ECHOES
ARE STARTING TO INTENSIFY WITH THIS AREA OF ENHANCEMENT AND WILL
LIKELY CONTINUE THOUGH THE EVENING. THE COMBINATION OF THIS
RELATIVELY STRONG MESOSCALE FORCING AND BROAD UPPER LEVEL DYNAMICS
IN THE RIGHT ENTRANCE REGION OF THE UPPER JET AND CYCLONIC FLOW
ALOFT WILL PRODUCE THE POTENTIAL FOR RAIN AND SNOW SHOWERS OVER
THE SRN HALF OF THE FORECAST AREA TONIGHT.
THE STRONG LIFT AND SLIGHTLY UNSTABLE ENVIRONMENT ALOFT WILL OCCUR
IN A FAVORABLE REGION OF THE DENDRITIC GROWTH ZONE...WHICH WILL
ALLOW THE PRECIPITATION RATES TO INCREASE LATE THIS EVENING AND
OVERNIGHT. THIS WILL COOL THE COLUMN AND CHANGE ANY RAIN OVER TO
ALL SNOW RELATIVELY QUICKLY. SO...WILL SEE THE POTENTIAL FOR
PERIODIC HEAVY SNOWFALL RATES DURING THIS TIME...WITH A QUICK 2 TO
4 INCHES OVER THE ADVISORY AREA.
A BRIEF BREAK IS POSSIBLE LATE MONDAY MORNING AND EARLY AFTERNOON
BEFORE ANOTHER BATCH OF RAIN AND/OR SNOW DEVELOPS ACROSS THE SRN
COUNTIES AGAIN LATE MONDAY AFTERNOON.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 406 PM CDT SUN APR 5 2015
THE FORECAST AREA WILL BECOME SITUATED BETWEEN VERY DRY CANADIAN
HIGH PRESSURE CENTERED OVER ONTARIO...AND A WARM FRONT WITH
INCREASING WARMTH AND MOISTURE OVER SRN MN THROUGH MUCH OF THE WEEK.
ALTHOUGH LONG RANGE MODELS ARE IN GOOD AGREEMENT THAT A THERMAL
BOUNDARY BECOMES THE FOCUS FOR ONGOING SHOWER CHANCES ACROSS CENTRAL
MINN AND NRN WISCONSIN. AT THIS TIME...THE IRON RANGE AND ARROWHEAD
REGIONS OF NE MINN ARE EXPECTED TO REMAIN DRY THROUGH THE WEEK WITH
THE INFLUENCE OF THE HIGH.
AT THIS TIME...THE BULK OF THE QPF/SNOW ASSOCIATED WITH THE
FRONTOGENESIS MON/MON NIGHT LOOKS TO AFFECT AREAS IN CENTRAL
MINNESOTA...AND NORTHERN WISCONSIN. CARRYING LIKELY POPS FOR
RAIN/SNOW MONDAY NIGHT FROM THE BRAINERD/MILLE LACS AREA...EAST INTO
THE HAYWARD LAKES.
FOCUS TURNS TO LONG WAVE TROUGH THAT DIGS ACROSS THE ROCKIES THROUGH
MID WEEK...DEEPENING INTO A CLOSED LOW IN THE CENTRAL PLAINS BY
THURSDAY. LATEST ECMWF/GFS/GEM ARE IN REASONABLE AGREEMENT THAT THE LOW
BECOMES CUT OFF AS IT SLOWLY LIFTS ACROSS IA/MN AND INTO THE WESTERN
GREAT LAKES REGION THROUGH FRIDAY. HAVE TRENDED TOWARDS THE SLOWER
ECMWF SOLUTION FOR POPS AND WINDS. ALTHOUGH VERY FAR OUT IN THE
EXTENDED RANGE...IF THIS LOW CAN MATERIALIZE...GUIDANCE SUGGESTS IT
WILL HAVE THE POTENTIAL TO BRING MUCH NEEDED QPF/RAINFALL OF A HALF
INCH OR MORE TO MUCH OF THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1242 AM CDT MON APR 6 2015
BAND OF SNOW IS IN THE PROCESS OF SETTING UP GENERALLY IN VICINITY
OF KHYR AND KBRD AS OF TAF ISSUANCE...BRINGING MVFR CEILINGS AND
IFR VISIBILITIES. THIS EXPECTED TO LAST THROUGH 15-18Z BEFORE
GRADUALLY RETURNING TO VFR. KDLH SHOULD BE ON THE FRINGES OF THIS
BAND...AND SHOULD HAVE A SHORTER PERIOD OF MAINLY MVFR CONDITIONS
UNTIL 12Z BEFORE ALSO RETURNING TO VFR. CONDITIONS TO REMAIN VFR
THROUGH THE REST OF THE TAF PERIOD...THOUGH CEILINGS WILL BE
LOWERING IN ADVANCE OF THE NEXT ROUND OF PRECIPITATION DUE IN
AROUND 06Z TONIGHT FOR KBRD AND KHYR.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 26 35 28 39 / 40 40 20 0
INL 22 43 25 45 / 0 10 10 0
BRD 28 39 27 45 / 60 40 20 10
HYR 28 39 28 45 / 70 40 20 10
ASX 27 36 29 42 / 50 40 20 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 10 AM CDT THIS MORNING FOR MNZ034-
036-038.
WI...WINTER WEATHER ADVISORY UNTIL 10 AM CDT THIS MORNING FOR
WIZ006>009.
LS...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 7 PM CDT TUESDAY
FOR LSZ144-145.
&&
$$
UPDATE...LE
SHORT TERM...BJT
LONG TERM...GRANING
AVIATION...LE
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
350 PM CDT Mon Apr 6 2015
.SHORT TERM: (Through Late Tonight)
Issued at 344 PM CDT Mon Apr 6 2015
Low pressure over the Great Plains continues to push a warm and
moist airmass into the region. Guidance suggests that convection
will blossom after 06-08Z somewhere over the CWFA as the nose of a
35-40kt low level jet runs into the 850mb baroclinic zone which is
draped over the area. Resulting isentropic lift should produce an
area of convection late tonight. This is all good in theory,
however short range guidance including the NAM and RAP show a decent
inversion above the level of free convection on forecast soundings
at various locations and times across the area. This puts
significant doubt on timing and coverage of convection late
tonight. Current feeling is that the best chance for storms to
develop will be 08Z or later, and possibly near the I-70 corridor in
Missouri. Ample pre-storm MUCAPE in excess of 1500-2000 J/kg and
persistent LLJ/isentropic lift should allow storms to increase in
coverage through 12Z. Also, with that kind of instability available
and forecast deep layer shear around 40kts, could see some storms
produce large hail. Only the uncertainty of where the storms will
form and ultimate areal coverage has dissuaded me from going with
likely or higher PoPs. As it stands, have 40-50% across the entire
CWFA late tonight, as this should allow the evening shift to
monitor latest trends and adjust as necessary.
Carney
.LONG TERM: (Tuesday through Next Monday)
Issued at 344 PM CDT Mon Apr 6 2015
Main forecast concern continues to be precipitation chances.
Obviously, threat of convection will be very high by Thursday and
Thursday night as deep upper level trof and associated surface
features push into the mid Mississippi Valley...the primary
problem is trying to pin down spatial and temporal convective
trends from tomorrow morning until the widespread and stormy
weather that is expected by Thursday.
The elevated storms that do develop late tonight should wind down
during the morning, leaving unstable but capped AMS blanketing the
area from Tuesday afternoon into Wednesday morning. Current
forecast soundings would suggest that southward sagging frontal
boundary will not be enough to bust through the warm mid level
temps, but there also seems to be some hints of very weak
shortwave energy ejecting into the area from the upper trof to our
west that could produce more elevated activity. In truth I can
probably dream up 2 or 3 scenarios on how convection could evolve
during this time, but with so much uncertainty for now plan on
sticking with going forecast trends, which generally indicate low
chance PoPs over most of the CWA during this time frame.
Fine-tuning will have to wait until this time period gets a bit
closer and specifics (hopefully) become clearer.
In spite of the considerable abiguity in precip trends heading into
mid week, today`s model guidance as well as that over the past
several days continue to point to widespread convection as we head
into Wednesday night and Thursday, with storms continuing into at
least Thursday evening. Intensifying surface low over the central
Plains on Wednesday afternoon will lead to increasing WAA
advection and isentropic ascent north of the frontal boundary.
This low level level forcing should then punch through the mid-
level cap which should begin to weaken by this time as heights
begin to fall in advance of the upper level trof. This round of
convection will work east as the synoptic front pushes north of
the area, placing the entire CWA in the warm sector of the surface
cyclone by Thursday morning. More convection should develop during
the day either from additional shortwave energy or perhaps the
effects of any residual boundaries from Wednesday night`s
activity, with a final shot of convection occurring along the cold
front as we head into the evening hours.
The synoptic models have backed off some on the instability
forecast, perhaps due to extensive cloudiness in the low levels as
well as a weakening of the nearly dry adiabtic lapse rates in the
EML that are progged early on during the forecast cycle. However,
kinematic and synoptic fields still strongly suggest a severe
weather threat...or more likely several episodes of severe
weather...from Wednesday night into Thursday evening. As alluded
to in the day3 and day 4 SPC discussions, threat of large hail and
damaging winds looks fairly substantial, while specific tornado
threat will at least be partially predicated on the specific
locations of fronts and any residual boundaries.
Uncertain how to handle the passage of the cold front/end of
thunderstorm threat. Initial thought was to slow it down a bit as a
common model bias is to be too fast with strong upper level systems,
but on the other hand convection along the front will likely be
screaming to the east, so effective bounday may race ahead of the
actual front. So, will continue thunderstorm threat across the
entire CWA on Thursday night, but will go dry by Friday.
It appears that this dry weather will continue into Saturday, with
thunderstorm chances returning by Sunday and Monday.
In spite of the fact that there will be considerable cloudiness,
there should be plenty of warmth through Thursday, with highs
primarily ranging from the middle 70s to lower 80s. The exception
to this may be over our northern counties on Wednesday, where
southward drift of the cold front will back off temps into the upper
60s and lower 70s. Arrival of the cold air will mean more
seasonable temps by Friday and Saturday.
Truett
&&
.AVIATION: (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1244 PM CDT Mon Apr 6 2015
MVFR flight conditions will prevail across much of the area this
afternoon. Ceilings will likely be dropping from AOA 2000 FT down
to between 1000-1900 FT through 20-22Z. Expect further lowering to
IFR conditions after 00Z. IFR conditions will prevail thereafter.
Short range model guidance is showing an increasing chance of
thunderstorms after 08Z Tuesday morning. However, the spread on
where the thunderstorms will form is quite large. While there is
increasing confidence that there will be storms, I have low
confidence on the areal coverage, strength, and location of those
storms.
Specifics for KSTL:
MVFR flight conditions will prevail at Lambert this afternoon.
18Z ob came in below 2000 FT and it`s likely the ceiling won`t
improve for the remainder of the day. Expect further lowering to
IFR conditions after 00Z. IFR conditions will prevail thereafter.
Short range model guidance is showing an increasing chance of
thunderstorms after 08Z Tuesday morning. However, the spread on
where the thunderstorms will form is quite large. While there is
increasing confidence that there will be storms, I have low
confidence on the areal coverage, strength, and location of those
storms.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1131 PM CDT Sun Apr 5 2015
.UPDATE:
Issued at 934 PM CDT Sun Apr 5 2015
Low to mid level cloudiness has spread northward through most of
our forecast area this evening. A small area or band of mainly
light showers moved through portions of southeast MO and was now
moving eastward through southwest IL; from VIH, UVV and FAM and
now about to move through SAR. This activity will likely shift
east-southeast of our forecast area by midnight. The latest HRRR
model run has most of its precipitation southeast of our forecast
area for late tonight. With a southwesterly low level jet
continuing to bring low level temperature and moisture advection
to the region, particularly to the southern half of our forecast
area, along with weak shortwaves moving eastward through the
region, still expecting additional isolated to scattered light
showers late tonight across southeast MO and southwest IL, with a
few sprinkles possible further north. Low temperatures tonight
will be much warmer compared to the previous two nights due to the
cloud cover, southerly surface winds, low level warm air advection,
and higher surface dew points. Minimum temperatures tonight should
be about 5-10 degrees above normal for early April.
GKS
&&
.SHORT TERM: (Through Late Tonight)
Issued at 414 PM CDT Sun Apr 5 2015
Southerly flow on the western side of the high pressure system over
the eastern seaboard is bringing warmer temperatures and increasing
low level moisture to the area. Even with deep mixing over the area
today, surface dewpoint temperatures are around 5 to 10 degrees
higher than they were yesterday. This moistening trend will
continue tonight and ceilings are expected to lower and thicken.
Warm south flow and abundant cloud cover should make for a warmer
night tonight with temperatures mainly in the mid to upper 40s; and
the more urbanized areas of St. Louis may not drop out of the lower
50s. All of this moisture advection is producing light QPF in the
models. However, it is fairly typical for this QPF to be overdone,
and the high resolution WRF models as well as the HRRR are showing
only very light/low probability precipitation. Have therefore
reduced PoPs to sight chance for most of the night...increasing to
low chance by 12Z over the eastern Ozarks.
Carney
.LONG TERM: (Monday through Next Sunday)
Issued at 414 PM CDT Sun Apr 5 2015
NWP output is maintaining fairly good run to run and model to model
consistency as we head into the new work week. Primary forecast
concern continues to be precipitation chances, with all solutions
maintaining the idea of a strong mid level cap dominating much of
the forecast area into Wednesday.
For Monday the odds of measurable rain still appear to be quite
small, with the rain chances (such as they are) tied to stratified
low level moisture trapped beneath the mid level inversion...which
also makes the odds of any convection quite small over most of the
CWA. In general have kept PoPs in the 15-30% range, and have
There are still indications that the increasing low level jet will
lead to the development of elevated convection on the eastern
fringes of the warmer mid level temps late Monday night and into
Tuesday morning. Forecast soundings from both NAM and GFS indicate
that genesis region for this development may be over
northern/central IL with the activity just clipping our CWA, but QPF
output from the ECMWF certainly suggests development much further to
the southwest...generally along the Mississippi River. For now I`ve
continued with high end chance/low likely PoPs for
northeast/easterns sections of our CWA. Elsewhere during this time
frame time PoPs should remain quite low as strong mid level cap
remains in place, although models do suggest some very weak
shortwaves and mid level moisture working across the area that could
lead to some elevated precip.
Frontal boundary drops south late Tuesday afternoon and Tuesday
night before stalling out from the northern Ozarks into southern IL
on Wednesday morning. Have continued chance PoPs in most areas
during this time, but once again these may be too high if the very
warm mid level temps forecast by the NAM/GFS verify.
Threat of storms should begin to ramp over parts of the CWA on Wednesday.
Not certain how much activity (if any) there will be Wednesday
morning, but all guidance indicates WAA ramping up during the
afternoon as upper level trofs begins to push into the western
Plains. This should set the stage for overrunning convection to
develop over northwest MO during the afternoon as low level ascent
is finally able to overcome the mid level cap. Elsewhere the cap
may still be tough to overcome, but with the boundary in the area
I have continued chance PoPs.
Several rounds of storms are expected from Wednesday night...Thursday...and
into Thursday night...as shortwave energy is ejected into the mid
Mississippi Valley from strong upper level trof pushing into the
Plains. These disturbances will finally erode the mid level
capping, and allow the energy from the increasingly unstable low
level AMS to be released, and have carried likely and higher PoPs
for most of the CWA during this period. Obviously, severe weather
remains a very real concern...especially on Thursday and Thursday
night...due to strength of upper level system, large scale shear,
and expected instability of the early summer airmass.
Passage of the cold front should end the thunderstorm threat over
eastern sections of the CWA on Friday morning, followed by drier and
cooler weather on Saturday. However, medium range models are
suggesting the development of return flow will mean another threat
of showers and storms by Sunday.
Truett
&&
.AVIATION: (For the 06z TAFs through 06z Monday Night)
Issued at 1131 PM CDT Sun Apr 5 2015
With low level moisture on the increase will continue to see mvfr
cigs advect north and northeast into forecast area. All taf sites
to be down to mvfr by 12z Monday and remain between 1500 and 3000
feet for rest of forecast period. Winds to persist from the south.
As for precipitation chances, scattered at best so kept mention
out of tafs for now.
Specifics for KSTL:
With low level moisture on the increase will continue to see mvfr
cigs advect north and northeast into forecast area. Cigs will be down
to mvfr by 11z Monday and remain between 1500 and 3000 feet for
rest of forecast period. Winds to persist from the south. As for
precipitation chances, scattered at best so kept only added vcnty
shower mention after 06z Tuesday.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
401 PM CDT MON APR 6 2015
.SHORT TERM...(TONIGHT THROUGH THURSDAY)
ISSUED AT 330 PM CDT MON APR 6 2015
FORECAST CONCERNS CONTINUE TO BE ON AND OFF PRECIPITATION CHANCES
THROUGH THE WEEK...TEMPERATURES...AND SEVERE POTENTIAL.
THE LOW CLOUDS MOVED IN OVERNIGHT...WITH SOME FOG AND DRIZZLE.
THE 12Z OAX SOUNDING WAS SATURATED TO 890MB/2500FT WITH 0.49PWAT.
A FEW STORMS DEVELOPED AROUND BOONE AND ANTELOPE COUNTIES AND
LIFTED TOWARD WAYNE...WITH A STRONGER CLUSTER NEAR WASHINGTON AND
BURT THAT LIFTED NORTHEAST ACROSS HARRISON...MONONA...AND SHELBY
WITH OTHERS IN SOUTHWEST IOWA. THE 12Z H5 MAP SHOWED A WEAK
SHORTWAVE WITH THIS FEATURE IN THE SOUTHWEST FLOW ALOFT. THE H5
CLOSED LOW WAS STILL OFF THE WASHINGTON/OREGON COAST WITH A BROAD
TROF. THERE WAS A WEAK WAVE IN THE FLOW AT H7 APPROACHING THE
LOCAL FORECAST AREA AT 12Z...WITH ANOTHER WEAK WAVE OVER COLORADO
AND YET FARTHER SOUTHWEST OVER SOUTHERN CALIFORNIA. THE H85
PATTERN HAD AN H85 LOW NEAR LBF WITH SOUTHWEST FLOW AHEAD OF IT
AND A POCKET OF 7C DEWPOINTS. THE 10-12DEG. H85 DEWPOINTS WERE
OVER SOUTHERN MO AND ARKANSAS INTO EASTERN OK. THE H7 DEWPOINTS
WERE BETTER OVER TN/AL/MS. THE +20 DEG. C H85 TEMPS WERE OVER TX
WITH THE THERMAL RIDGE NOSING TOWARD OMA AT +12 DEG C.
THE LATEST VISIBLE SATELLITE IMAGERY WAS CLOUDY MOST AREAS...WITH
SOME BUMPY CLOUDS NEAR SD INTO IOWA AND A FEW THINNER SPOTS TOWARD
FAIRBURY... THE SURFACE FRONT WAS NEAR YANKTON TO ONL WITH A
DRYLINE NEAR KGBD KANSAS AND THE WARM FRONT FROM SALINA TO
WICHITA WITH THE CLEARING NEAR THERE. TEMPERATURES WERE IN THE
50S TO LOWER 60S WITH 70S AND 80S SOUTH OF THE WARM FRONT.THE LOCAL
RADAR WAS MAINLY DRY WITH ECHOES TO THE NORTHEAST INTO IOWA.
STILL SOME PATCHY FOG WITH VSBYS 2 TO 4 MILES IN SPOTS.
TONIGHT...SURFACE LOW PRESSURE TRIES TO ORGANIZE A LITTLE FARTHER
SOUTH IN KANSAS WITH NORTHEAST FLOW PREVAILING ACROSS THE FORECAST
AREA. ONE THING TO WATCH WILL BE A 50KT LOW LEVEL JET THAT
INCREASES ACROSS KANSAS INTO MISSOURI. THE 4KM WRF HAS A CLUSTER OF
STORMS DEVELOPING AND MOVING ACROSS NORTHERN KANSAS AND MISSOURI.
THE RAP HAS SHOWERS/TSTORMS IN SOUTHEAST NEBRASKA. IN OUR
FORECAST AREA...ANY PRECIPITATION LOOKS SPOTTY. DO HAVE HIGHER
POPS IN THE SOUTHEAST AND ALSO IN THE NORTHEAST BY MORNING. THE
GFS DOES INCREASE INSTABILITY TOWARD 1000J/KG IN THE SOUTHEAST. ANY
STRONGER STORMS COULD PRODUCE SOME HAIL. THERE MAY BE AN ENHANCED
BAND OF LIGHT PRECIP IN NORTHEAST NEBRASKA BY MORNING NEAR AN
INVERTED TROF AND SOME SHORTWAVE ENERGY PASSES THROUGH.
TUESDAY...THE SURFACE LOW PRESSURE TRACKS NORTHEAST TOWARD SOUTHEAST
NEBRASKA OR NORTHEAST KANSAS...WITH A H85 CIRCULATION OVER THE
FORECAST AREA. THE PRECIPITATION (SHOWERS AND ISOLATED
THUNDERSTORMS) SHOULD MOVE ACROSS THE FORECAST AREA DURING THE
DAY. TEMPERATURES AGAIN SHOULD BE IN THE 50S...WITH 60S CLOSER TO
THE SURFACE LOW FALLS CITY COULD BREAK OUT TO THE LOWER 70S.
TUESDAY NIGHT INTO WEDNESDAY NIGHT AHEAD OF THE STRONGER
SHORTWAVE...FLOW BACKS AND RE-FOCUSES THE LOW LEVEL FLOW WITH
PRECIPITATION CHANCES AGAIN ON THE INCREASE. THE BETTER COVERAGE
SHOULD BE THE SOUTHEAST PART OF THE FORECAST AREA. THE DAY 3 SPC
OUTLOOK HAS THIS AREA ALSO IN THE SLIGHT RISK AND THIS SEEMS
REASONABLE AND WILL BE DEPENDENT ON THE THE SURFACE LOW TRACK. THE
NAM/EC IS NOT QUITE AS FAR NORTH AT THE GFS. SO THIS WILL BE
SOMETHING TO KEEP AN EYE ON.
THE FRONT PUSHES THROUGH THURSDAY WITH THE UPPER LEVEL TROF TO THE
WEST. POST-FRONT SHOWERS WILL CONTINUE INTO THURSDAY WITH
NORTHWEST WINDS.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 330 PM CDT MON APR 6 2015
THE STORM SYSTEM PULLS AWAY THURSDAY NIGHT. THERE IS A SMALL
CHANCE FOR SHOWERS/ISOLATED THUNDERSTORMS FRIDAY NIGHT AND
SATURDAY. ON AND OFF PRECIPITATION CHANCES CONTINUE INTO THE
WEEKEND.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1209 PM CDT MON APR 6 2015
CIGS CONT TO BE IN IFR RANGE THIS MRNG...BUT MOST LOCATIONS
SHOULD BECOME MVFR BY LATE AFTN AND INTO THE EVENING HOURS. WE
HAVE HAD SOME DZ AT ALL 3 SITES THIS MRNG...BUT THIS SHOULD
GENERALLY BE OVER BY EARLY AFTN. WILL LEAVE THAT TAF SITES DRY FOR
THE REST OF THE PERIOD...ALTHOUGH WE MAY SEEN AN INCREASE IN
SHOWERS ON TUE MRNG TO END THIS CYCLE BUT CONFIDENCE IS LOW. CIGS
SHOULD LOWER AGAIN AFTER MIDNIGHT TO IFR AT KOMA AND LIFR AT
KOFK/KLNK.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
954 PM EDT TUE APR 7 2015
.SYNOPSIS...
A FRONTAL BOUNDARY STALLED FROM THE OHIO VALLEY TO THE MID
ATLANTIC COAST WILL PROVIDE PERIODS OF UNSETTLED WEATHER AROUND
THE REGION THROUGH THURSDAY. TEMPERATURES WILL GENERALLY SUPPORT
RAIN DURING THE DAYLIGHT HOURS...BUT MAY TAIL OFF TO BELOW
FREEZING AT NIGHT...PROVIDING A CHANCE FOR SOME LIGHT FREEZING
RAIN OR SLEET BOTH LATE TONIGHT AND AGAIN LATE WEDNESDAY NIGHT FOR
THE MOHAWK VALLEY...WESTERN CATSKILLS AND NORTHERN POCONOS.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
950 PM UPDATE...
LATEST HRRR GUIDANCE FORECASTS THE NEXT SHORT WAVE / IMPULSE INVOF
OF ELEVATED WARM FRONT TO PUSH PRECIP INTO WESTERN FA AROUND 6Z.
THE PRECIPITATION WILL GRADUALLY SPREAD NORTH AND EAST THROUGHOUT
THE PREDAWN HOURS UNTIL RAIN SHOWERS COVER THE ENTIRE REGION FOR
THE MID-MORNING COMMUTE.
A VERY SLIGHT POSSIBILITY EXISTS FOR SLEET OR FREEZING RAIN OVER
THE NORTHERN FA, WHERE COLD AIR BLEEDS OFF OF THE HIGHER TERRAIN.
POPS ARE VERY LOW (MAINLY SLIGHT CHANCE TO LOW CHANCE) DURING THE
PERIOD OF THE MORNING WHEN TEMPS ARE MARGINAL, SO WILL KEEP THE
THREAT MINIMIZED. SEE NO NEED TO RAISE A FLAG FOR SUCH A LOW
PERCENTAGE EVENT.
4 PM UPDATE...
FAST ZONAL FLOW ALOFT WITH MINOR IMPULSES MOVING
ALONG AN 850-700 MB WARM FRONT OVER THE REGION WILL PROVIDE THE
NECESSARY FORCING FOR PERIODIC BOUTS OF PRECIPITATION THROUGH
THURSDAY. TIMING IS DIFFICULT IN THIS TYPE OF PATTERN TO GET A
HANDLE ON EXACTLY WHEN AND WHERE IT WILL HAPPEN...BUT 12Z MODELS
ARE SHOWING A LULL IN ACTION AS THIS FIRST WAVE DEPARTS THIS
EVENING...FOLLOWED BY A RESURGENCE OF ENERGY AFTER MIDNIGHT
AFFECTING MAINLY OUR SW ZONES...THEN THE NEPA AND WRN CATSKILLS
SHORTLY AFTER DAYBREAK. COLDER AND SLIGHTLY DRIER AIRMASS UNDER
HIGH PRESSURE OVER NRN NEW YORK WILL ALLOW FOR OUR NORTHERN AND
EASTERN ZONES TO DROP TO NEAR AND BELOW FREEZING BEFORE PRECIP
STARTS. EARLIER FORECASTS HAD MENTION OF FREEZING RAIN/SLEET FOR
THE MOHAWK VALLEY AND WRN CATS LATE TONIGHT AND EARLY WEDNESDAY
BEFORE WARMING. 12Z FORECAST SOUNDINGS AND GENERAL THICKNESS
FIELDS MAINTAIN THIS IDEA. NO WINTER HEADLINES AT THIS TIME AS THE
POPS ARE STILL UNCERTAIN AS TO THIS HAPPENING BEFORE TEMPS
WARM...AND TEMPS ARE RIGHT ON THE FREEZING LINE ANYWAY.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
TIMING CONTINUES TO BE PROBLEMATIC IN THIS FAST PATTERN THROUGH
THURSDAY...HOWEVER THE 12Z GUIDANCE IS IN FAIR AGREEMENT ON A
COUPLE OF KEY PERIODS WHERE MOST OF OUR FORECAST AREA SHOULD SEE
PRECIP. A SURGE ALONG THE WARM FRONT ALOFT OCCURS WEDNESDAY
MORNING...FOLLOWED BY ANOTHER LULL WEDNESDAY NIGHT AND THURSDAY
MORNING. GREATER AMPLIFICATION OF THE PATTERN THEN TAKES PLACE
WITH A DEEPER BOUNDARY LAYER FLOW INCREASING ON THURSDAY AFTERNOON
WITH ADDITIONAL PERIODS OF RAIN SWEEPING INTO THE AREA.
WE CONTINUE TO SEE SIGNS OF CLASSIC COLD AIR DAMMING ALONG OUR
EASTERN ZONES AGAIN WEDNESDAY THROUGH THURSDAY WITH TEMPERATURES
STRUGGLING TO GET OUT OF THE UPPER 30S TOMORROW FROM THE CATSKILLS
TO THE NRN POCONOS. THIS WILL AGAIN SET THE STAGE FOR TEMPERATURES
TO SLIP BELOW FREEZING IN THESE AREAS AS SOME LINGERING
PRECIPITATION WORKS IN AGAIN LATER WEDNESDAY NIGHT AND EARLY
THURSDAY FOR ANOTHER POTENTIAL ROUND OF FREEZING RAIN OR SLEET.
WHEN ALL IS SAID AND DONE THURSDAY AFTERNOON...THERE COULD BE
QUITE A TEMPERATURE GRADIENT FROM THE FINGER LAKES TO THE POCONOS
RANGING FROM THE 50S TO THE UPPER 30S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
3 PM UPDATE...
THE UNSETTLED PATTERN WILL CONTINUE THROUGH THE FIRST PART OF THE
EXTENDED WITH FAIR WEATHER TO FOLLOW FOR THE WEEKEND.
EXPECT SHOWERS THURSDAY NIGHT ALONG AND AHEAD OF A WARM FRONT WITH
TEMPS NUDGING UP OVERNIGHT. WE ALSO CONTINUE TO MENTION THE SLIGHT
CHANCE OF ELEVATED CONVECTION OVER WESTERN ZONES. FOR FRIDAY,
STILL EXPECTING THE AREA TO BRIEFLY BREAK INTO THE WARM SECTOR
BEFORE A COLD FRONT MOVES THROUGH IN THE AFTERNOON. SHOWALTER
INDICES AND/OR LIFTED INDICES GET NEAR OR SLIGHTLY BELOW ZERO.
PRECIPITABLE WATER VALUES GET PAST 1.25 INCHES.. CAPE ITSELF WILL
BE VERY LIMITED...WHICH WILL HOLD BACK COVERAGE OF ANY
THUNDER...BUT THERE APPEARS TO BE GREAT JET SUPPORT VIA FORCED
ASCENT OF RIGHT ENTRANCE REGION. SO THERE WILL AT LEAST BE A GOOD
BATCH OF SHOWERS WITH THE FRONTAL PASSAGE. CONTINUED THE MENTION
OF THUNDER FOR MOST OF THE CWA BUT EXCLUDED NW AREAS OVER THE LAKE
PLAIN SINCE FRONT WILL CROSS THIS AREA EARLIER IN THE DAY.
ISOLATED LIGHT SHOWERS COULD STILL OCCUR IN THE BRIEF COLD AIR
ADVECTION BEHIND THE FRONT SATURDAY...MAINLY CENTRAL NY...BUT IN
GENERAL THINGS WILL DRY OUT THIS WEEKEND. HIGH PRESSURE SUNDAY
SHOULD YIELD SUNSHINE AND TEMPERATURES EDGING BACK ABOVE
CLIMATOLOGY AFTER A CHILLY DAWN. FURTHER WARMING EXPECTED EARLY
NEXT WEEK WITH THE NEXT CHANCE OF RAIN ARRIVING LATE MONDAY INTO
TUESDAY.
&&
.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
A COMPLEX FORECAST IS EXPECTED FOR THE NEXT 24 HOURS AS A FRONTAL
BOUNDARY HAVE STALLED OVER THE AREA. THIS BOUNDARY WILL OSCILLATE
OVER THE REGION AND FLIGHT CONDITIONS WILL VARY DEPENDING ON
WHERE THIS BOUNDARY SHIFTS. ALONG THIS BOUNDARY... FLIGHT
CONDITIONS WILL BE POOR AND MAY BECOME LOW END IFR IN CIGS AND
VISBYS. FLIGHT CONDITIONS SHOULD IMPROVE FOR A BRIEF PERIOD
TONIGHT AS A LULL IN THE PRECIP IS EXPECTED. THE NEXT WAVE ALOFT
IS EXPECTED TO MOVE OVER THE REGION AROUND MIDNIGHT BRINGING THE
NEXT CHANCE FOR PRECIP. EXPECT WIDESPREAD RAIN... SOME OF THEN
ACTIVITY MAY BECOME A WINTRY MIX.. BUT AS CONFIDENCE IS LACKING ON
SFC TEMPS FALLING BELOW FREEZING... DECIDED TO LEAVE MENTION OUT
OF TAF ATTM. KRME HAS THE BEST CHANCE TO SEE A BRIEF PERIOD OF A
WINTRY MIX LATE TONIGHT. WIDEPSREAD RAIN SHOWER MAY CONTINUE
THROUGH WED EVENING.
WINDS WILL REMAIN LIGHT TONIGHT... AND INCREASE SHORTLY AFTER
SUNRISE TOMORROW FROM SOUTH/SOUTHEAST AROUND 12 KNOTS.
.OUTLOOK...
WED-FRI...BUSY PATTERN WITH WAFFLING FRONTAL BOUNDARY REMAINING
IN THE VICINITY...AND WAVES OF SHRA PLUS ASSOCIATED RESTRICTIONS
MOVING ALONG IT. SLIGHT CHC TSRA AS WELL FRI.
SAT...MAINLY VFR BUT ISOLATED -SHRA STILL POSSIBLE OVER CENTRAL
NY.
SUN...VFR.
.HYDROLOGY...
RIVERS WILL CONTINUE TO RUN HIGH AS WE CONTINUE THE GRADUAL SNOW
MELT RUN OFF FROM THE NORTH FACING SLOPES AND DEEP WOODS THIS
WEEK. THAT COUPLED WITH THESE PERIODIC EPISODES OF RAIN WILL HAVE
US FLIRT WITH A MINOR RIVER FLOOD POTENTIAL IN OUR MOST SENSITIVE
HEADWATER AREAS. AT THIS TIME...THE RAIN AMOUNTS IN THE MODELS
LOOK TOO ROBUST THROUGH THURSDAY...AS SEVERAL MODELS ARE OVER
PERFORMING WITH EVEN TODAY`S RAIN...BUT AS THE DEEPER SYSTEM OVER
THE UPPER MIDWEST WORKS EAST THIS WEEKEND IS WHEN WE WILL REALLY
NEED TO PAY ATTENTION AS THEN CONFIDENCE IN MORE RIVER POINTS
REACHING FLOOD STAGE MAY INCREASE. IN THE MEANTIME...THE NEXT 72
HOURS OR SO SHOULD BE OK WITH RIVERS RISING 3/4 TO NEAR BANKFULL
AT TIMES.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JAB
NEAR TERM...DJP
SHORT TERM...JAB
LONG TERM...PCF
AVIATION...KAH
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
544 PM EDT MON APR 6 2015
.SYNOPSIS...
A FRONTAL SYSTEM OVER THE NORTH COUNTRY EARLY TONIGHT WILL MOVE
SOUTH OF THE REGION BY TUESDAY AS A RIDGE OF HIGH PRESSURE BUILDS
SOUTH FROM CANADA. THIS HIGH PRESSURE AREA WILL BE OVER THE NORTH
COUNTRY TUESDAY NIGHT THROUGH MIDDAY ON WEDNESDAY BEFORE ANOTHER
SURGE OF MOISTURE MOVE NORTHEAST FROM THE OHIO VALLEY WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT BRINGING MORE RAIN AND SNOW SHOWERS
TO THE REGION.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 538 PM EDT MONDAY...QUICK UPDATE TO TIGHTEN TEMPERATURE
GRADIENT AND ADJUST SOME OF THE NEAR-TERM POPS/WEATHER.
TEMPERATURES JUST NORTH OF THE BOUNDARY REMAIN FROM 30-36F WHILE
SOME LOCATIONS EVEN AS CLOSE AS SPRINGFIELD VERMONT HAVE REACHED
50F. BECAUSE TEMPERATURES REMAIN COOLER IN THE NORTHERN
COUNTIES...HAVE ADDED IN MORE MENTION OF SNOW OVER THE NEXT COUPLE
OF HOURS. ALSO TWEAKED POPS TO BETTER REPRESENT RADAR AND FORECAST TRENDS
FOR THE EVENING. BAND OF PRECIP OVER THE NORTHERN TIER WILL LIFT
A BIT FURTHER NORTHWARD BEFORE STALLING AND GRADUALLY DIMINISHING.
ADDITIONAL SHOWERY PRECIP POSSIBLE LATER THIS EVENING OVER
SOUTHERN VERMONT AS WELL.
PREVIOUS DISCUSSION FROM 404 PM MONDAY...
COMPOSITE RADAR LOOP SHOWING LIGHT SNOW SHOWERS OVERRUNNING A
FRONTAL BOUNDARY ACROSS NORTHERN NEW YORK AND VERMONT AT THIS
TIME. COMPOSITE RADAR LOOP SHOWING MORE SHOWER ACTIVITY WORKING
NORTHEAST FROM THE OHIO VALLEY AT THIS TIME...SO EXPECTING THIS
ACTIVITY TO WORK INTO THE SOUTHERN PORTION OF THE FORECAST AREA
OVERNIGHT. VISIBLE SATELLITE LOOP ALSO SHOWING MORE CLOUD COVER
HEADING FOR SOUTHERN VERMONT FROM THE OHIO VALLEY AT THIS TIME AS
WELL. GIVEN CLOUD COVER HAVE GONE A BIT WARMER THAN MOS GUIDANCE
FOR MIN TEMPERATURES TONIGHT.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 404 PM EDT MONDAY...A RIDGE OF HIGH PRESSURE WILL BUILD
SOUTH FROM CANADA ON TUESDAY. HAVE GONE WITH JUST SLIGHT CHANCE
POPS FOR RAIN OR SNOW SHOWERS TUESDAY MORNING...AND THEN EXPECTING
THE REMAINDER OF THE DAY TO REMAINDER OF THE DAY TO BE DRY. THIS
RIDGE OF HIGH PRESSURE WILL THEN REMAIN OVER THE NORTH COUNTRY
TUESDAY NIGHT AND THROUGH MIDDAY ON WEDNESDAY. ANOTHER SURGE OF
MOISTURE WILL WILL MOVE NORTHEAST FROM THE OHIO VALLEY WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT WITH MORE OVERRUNNING RAIN AND SNOW
SHOWERS. MODEL ALSO SHOWING AN INVERTED TROUGH WILL SET UP ACROSS
THE SAINT LAWRENCE VALLEY BY LATE WEDNESDAY AFTERNOON INTO
WEDNESDAY NIGHT. HAVE GONE WARMER THAN THE GFS MOS GUIDANCE FOR
MIN TEMPERATURES TUESDAY NIGHT AND WEDNESDAY NIGHT...AS THIS
GUIDANCE LOOKS TOO COOL...ESPECIALLY GIVEN CLOUD COVER OVER THE
REGION.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 336 PM EDT MONDAY...12Z GLOBAL SUITE OF GUIDANCE IS IN GOOD
AGREEMENT ON THE EXPECTED PATTERN. FOR MUCH OF THE PERIOD, LARGE-
SCALE MID-/UPPER-LEVEL HEIGHT FALLS REBUILD INTO THE INTERMOUNTAIN
WEST, WHICH LEADS TO DOWNSTREAM UPPER RIDGING ACROSS THE EASTERN
THIRD OF THE COUNTRY. IT APPEARS THAT A PATTERN CHANGE TOWARD
MILDER WEATHER IS IN THE OFFING. IT`S MORE REPRESENTATIVE OF
SPRING THAN WHAT WE`VE EXPERIENCED RECENTLY, AT LEAST.
THURSDAY: LOW-LEVEL WARM ADVECTION/ISENTROPIC ASCENT REGIME WITH
WARMING 1000-500 MB THICKNESSES PRODUCES MAINLY LIGHT RAIN. THE ONE
EXCEPTION WILL BE ACROSS EASTERN VT IN THE MORNING, AS COLD-AIR
DAMMING SIGNATURE EVIDENT IN SEA-LEVEL PRESSURE AND THICKNESS FILEDS
SUGGEST NEAR TO SUB-FREEZING LOW-LEVELS IN THESE AREAS. STRENGTH OF
WARM ADVECTION SHOULD READILY OVERCOME THIS LAYER, THOUGH, SO PERIOD
OF FROZEN PRECIP IS BRIEF. HIGHS LOWER 40S EASTERN VT TO AROUND 50
FOR ST. LAWRENCE VALLEY.
THURSDAY NIGHT: BEST SURGE OF WARM FRONTAL PRECIP COMES IN DURING
THE EARLY PART OF THURSDAY NIGHT. SOUTH WINDS ALSO ON THE
INCREASE, SO WHILE POPS ARE GENERALLY IN THE LIKELY CATEGORY, I DO
SHOW A RELATIVE MIN IN POPS IN THE CHAMPLAIN VALLEY, AS BREEZY SOUTH
WINDS TEND TO LIMIT QPF LOCALLY. ASIDE FROM EASTERN VT WHERE MID
30S ARE FORECAST, LOWS OTHERWISE ARE UPPER 30S TO THE MID 40S
GIVEN ABUNDANCE OF CLOUDS/PRECIP.
FRIDAY: 500 MB RIDGE CONTINUES TO AMPLIFY AHEAD OF A DIGGING
SHORTWAVE INTO THE NORTHERN/CENTRAL PLAINS. WITH MUCH OF THE NORTH
COUNTRY IN A WARM SECTOR BETWEEN APPROACHING OCCLUDED FRONT, WARM
THERMAL AND MOISTURE ADVECTION SHOULD BE UNDERWAY ON FRIDAY. IN
FACT, PWAT VALUES DO CLIMB OVER AN INCH PER THE 12Z GFS. SHOULD SEE
PERIODS OF LIGHT SHOWERS IN THE WARM SECTOR, WITH THE GREATEST POPS
TIED MOSTLY TO THE COLD FRONT. 925/850 MB TEMPS WARM TO AROUND +10C,
THOUGH LIKELY PARTIAL TO MOSTLY CLOUDY SKIES ONLY YIELD HIGHS IN THE
MID TO UPPER 50S. RESULTING SNOW MELT SHOULD PRODUCE SOME RISE IN
RIVER LEVELS, THOUGH CURRENT STAGES STILL ARE PRETTY LOW.
FRIDAY NIGHT: OCCLUDED FRONTAL BOUNDARY MOVES THROUGH THE NORTH
COUNTRY FRIDAY NIGHT. RAIN SHOULD BE FOCUSED MORE ALONG THE FRONT.
SOME QUESTION AS TO HOW MUCH QPF FALLS WITH THE FRONT AND PENDING
HOW MUCH SNOW CAN MELT, COULD HAVE TO KEEP AN EYE ON OUR RIVERS
FOR RISES. THOUGH TEMPERATURES ALOFT COOL BEHIND THE FRONT, RH
PROFILES SUGGEST AT LEAST PARTIAL CLOUDINESS, WHICH KEEPS LOWS
STILL IN THE 30S/AROUND 40.
SATURDAY: SECONDARY COLD FRONT SWEEPS ACROSS THE NORTH COUNTRY
DURING THE DAY SATURDAY. I`VE SHOWN CHANCE POPS ACROSS NORTHERN
ZONES FOR SATURDAY, WITH HIGHS IN THE UPPER 40S/AROUND 50.
SATURDAY NIGHT - SUNDAY: GENERALLY DRY AS HIGH PRESSURE BUILDS IN,
BUT COLD ADVECTION REGIME BRINGS 850 MB TEMPS BACK DOWN TO -4 TO -
6C. CONTINUED DRY WEATHER INTO SUNDAY UNDER SURFACE HIGH PRESSURE.
USED SUPERBLEND GUIDANCE FOR TEMPS THIS PERIOD, WITH LOWS IN THE
UPPER 20S/LOWER 30S SATURDAY NIGHT AND HIGHS UPPER 40S TO MID 50S.
PATTERN THEN GETS A BIT LESS CERTAIN SUNDAY NIGHT INTO MONDAY, BUT
INDICATIONS ARE FOR A RETURN TO MILDER WEATHER FOR EARLY NEXT
WEEK. LARGELY STUCK WITH BLENDED GUIDANCE TO CLOSE THE EXTENDED.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...A MIX OF FLIGHT CATEGORIES BETWEEN VFR TO
IFR AS WARM FRONT LIFTS TO ABOUT THE CANADIAN BORDER, AND SAGS
BACK SOUTHWARD LATER THIS EVENING. PRETTY BUSY TAF PERIOD WITH LOW
VISIBILITIES AND MOUNTAINS OBSCURED BY LOW CEILINGS, BUT OVERALL
LIMITED IMPACT TO AVIATION GROUND OPERATIONS.
COMPOSITE RADAR SHOWS AN EAST-WEST BAND OF ECHOES PRODUCING IFR
VISIBILITY RAIN/SNOW MIX NOW LIFTING NORTHWARD ACROSS THE TAFS.
FURTHER SOUTH THOUGH, PRECIPITATION HAS ALREADY ENDED - AT LEAST
TEMPORARILY AT RUT. VISIBILITIES SHOULD BEGIN TO IMPROVE FROM
SOUTH TO NORTH AS FRONT LIFTS NORTH THROUGH 00Z WEDNESDAY. EXPECT
A BREAK IN PRECIPITATION AND IMPROVEMENT IN VISBYS UNTIL AROUND
00-02Z. APPROACHING MOISTURE FROM THE OHIO VALLEY IS PROGGED BY
THE HRRR TO SHIFT INTO RUT, WHILE WARM FRONT TO THE NORTH BEGINS
ITS SAG SOUTHWARD. THAT SHOULD PRODUCE ANOTHER PERIOD OF MVFR TO
IFR VISIBILITIES IN RAIN/SNOW. WINDS LIGHT/VARIABLE BECOMING
SOUTH UNDER 10 KTS, THEN SHIFTING TO NORTH UNDER 10 KTS OVERNIGHT
AS BOUNDARY SAGS BACK SOUTHWARD.
FOR TUESDAY, ANY LINGERING PRECIPITATION WILL REMAIN PRIMARILY AT
RUT IN THE MORNING HOURS. EXPECT MOSTLY VFR CONDITIONS ELSEWHERE.
OUTLOOK 18Z TUESDAY THROUGH FRIDAY...
18Z TUESDAY THROUGH 18Z WEDNESDAY...TRENDING VFR AT ALL TERMINALS
WITH HIGH PRESSURE BUILDING SOUTH INTO THE AREA.
18Z WEDNESDAY THROUGH 06Z THURSDAY...TRENDING MVFR/OCCNL IFR IN
PERIODS OF LIGHT RAIN/SNOW WITH ADDITIONAL ENERGY RIDING ALONG
SEMI-STATIONARY FRONT ACROSS THE REGION.
06Z THURSDAY THROUGH 00Z FRIDAY...TRENDING VFR WITH HIGH PRESSURE,
THOUGH BKN/OVC CIGS STILL LIKELY.
00Z FRIDAY THROUGH 00Z SATURDAY...IFR/MVFR IN STEADIER RAIN AND
SNOW SHOWERS WITH ADDITIONAL ENERGY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...WGH
NEAR TERM...WGH/MUCCILLI
SHORT TERM...WGH
LONG TERM...LOCONTO
AVIATION...LOCONTO
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
404 PM EDT MON APR 6 2015
.SYNOPSIS...
A FRONTAL SYSTEM OVER THE NORTH COUNTRY EARLY TONIGHT WILL MOVE
SOUTH OF THE REGION BY TUESDAY AS A RIDGE OF HIGH PRESSURE BUILDS
SOUTH FROM CANADA. THIS HIGH PRESSURE AREA WILL BE OVER THE NORTH
COUNTRY TUESDAY NIGHT THROUGH MIDDAY ON WEDNESDAY BEFORE ANOTHER
SURGE OF MOISTURE MOVE NORTHEAST FROM THE OHIO VALLEY WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT BRINGING MORE RAIN AND SNOW SHOWERS
TO THE REGION.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 404 PM EDT MONDAY...COMPOSITE RADAR LOOP SHOWING LIGHT SNOW
SHOWERS OVERRUNNING A FRONTAL BOUNDARY ACROSS NORTHERN NEW YORK
AND VERMONT AT THIS TIME. COMPOSITE RADAR LOOP SHOWING MORE SHOWER
ACTIVITY WORKING NORTHEAST FROM THE OHIO VALLEY AT THIS TIME...SO
EXPECTING THIS ACTIVITY TO WORK INTO THE SOUTHERN PORTION OF THE
FORECAST AREA OVERNIGHT. VISIBLE SATELLITE LOOP ALSO SHOWING MORE
CLOUD COVER HEADING FOR SOUTHERN VERMONT FROM THE OHIO VALLEY AT
THIS TIME AS WELL. GIVEN CLOUD COVER HAVE GONE A BIT WARMER THAN
MOS GUIDANCE FOR MIN TEMPERATURES TONIGHT.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 404 PM EDT MONDAY...A RIDGE OF HIGH PRESSURE WILL BUILD
SOUTH FROM CANADA ON TUESDAY. HAVE GONE WITH JUST SLIGHT CHANCE
POPS FOR RAIN OR SNOW SHOWERS TUESDAY MORNING...AND THEN EXPECTING
THE REMAINDER OF THE DAY TO REMAINDER OF THE DAY TO BE DRY. THIS
RIDGE OF HIGH PRESSURE WILL THEN REMAIN OVER THE NORTH COUNTRY
TUESDAY NIGHT AND THROUGH MIDDAY ON WEDNESDAY. ANOTHER SURGE OF
MOISTURE WILL WILL MOVE NORTHEAST FROM THE OHIO VALLEY WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT WITH MORE OVERRUNNING RAIN AND SNOW
SHOWERS. MODEL ALSO SHOWING AN INVERTED TROUGH WILL SET UP ACROSS
THE SAINT LAWRENCE VALLEY BY LATE WEDNESDAY AFTERNOON INTO
WEDNESDAY NIGHT. HAVE GONE WARMER THAN THE GFS MOS GUIDANCE FOR
MIN TEMPERATURES TUESDAY NIGHT AND WEDNESDAY NIGHT...AS THIS
GUIDANCE LOOKS TOO COOL...ESPECIALLY GIVEN CLOUD COVER OVER THE
REGION.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 336 PM EDT MONDAY...12Z GLOBAL SUITE OF GUIDANCE IS IN GOOD
AGREEMENT ON THE EXPECTED PATTERN. FOR MUCH OF THE PERIOD, LARGE-
SCALE MID-/UPPER-LEVEL HEIGHT FALLS REBUILD INTO THE INTERMOUNTAIN
WEST, WHICH LEADS TO DOWNSTREAM UPPER RIDGING ACROSS THE EASTERN
THIRD OF THE COUNTRY. IT APPEARS THAT A PATTERN CHANGE TOWARD
MILDER WEATHER IS IN THE OFFING. IT`S MORE REPRESENTATIVE OF
SPRING THAN WHAT WE`VE EXPERIENCED RECENTLY, AT LEAST.
THURSDAY: LOW-LEVEL WARM ADVECTION/ISENTROPIC ASCENT REGIME WITH
WARMING 1000-500 MB THICKNESSES PRODUCES MAINLY LIGHT RAIN. THE ONE
EXCEPTION WILL BE ACROSS EASTERN VT IN THE MORNING, AS COLD-AIR
DAMMING SIGNATURE EVIDENT IN SEA-LEVEL PRESSURE AND THICKNESS FILEDS
SUGGEST NEAR TO SUB-FREEZING LOW-LEVELS IN THESE AREAS. STRENGTH OF
WARM ADVECTION SHOULD READILY OVERCOME THIS LAYER, THOUGH, SO PERIOD
OF FROZEN PRECIP IS BRIEF. HIGHS LOWER 40S EASTERN VT TO AROUND 50
FOR ST. LAWRENCE VALLEY.
THURSDAY NIGHT: BEST SURGE OF WARM FRONTAL PRECIP COMES IN DURING
THE EARLY PART OF THURSDAY NIGHT. SOUTH WINDS ALSO ON THE
INCREASE, SO WHILE POPS ARE GENERALLY IN THE LIKELY CATEGORY, I DO
SHOW A RELATIVE MIN IN POPS IN THE CHAMPLAIN VALLEY, AS BREEZY SOUTH
WINDS TEND TO LIMIT QPF LOCALLY. ASIDE FROM EASTERN VT WHERE MID
30S ARE FORECAST, LOWS OTHERWISE ARE UPPER 30S TO THE MID 40S
GIVEN ABUNDANCE OF CLOUDS/PRECIP.
FRIDAY: 500 MB RIDGE CONTINUES TO AMPLIFY AHEAD OF A DIGGING
SHORTWAVE INTO THE NORTHERN/CENTRAL PLAINS. WITH MUCH OF THE NORTH
COUNTRY IN A WARM SECTOR BETWEEN APPROACHING OCCLUDED FRONT, WARM
THERMAL AND MOISTURE ADVECTION SHOULD BE UNDERWAY ON FRIDAY. IN
FACT, PWAT VALUES DO CLIMB OVER AN INCH PER THE 12Z GFS. SHOULD SEE
PERIODS OF LIGHT SHOWERS IN THE WARM SECTOR, WITH THE GREATEST POPS
TIED MOSTLY TO THE COLD FRONT. 925/850 MB TEMPS WARM TO AROUND +10C,
THOUGH LIKELY PARTIAL TO MOSTLY CLOUDY SKIES ONLY YIELD HIGHS IN THE
MID TO UPPER 50S. RESULTING SNOW MELT SHOULD PRODUCE SOME RISE IN
RIVER LEVELS, THOUGH CURRENT STAGES STILL ARE PRETTY LOW.
FRIDAY NIGHT: OCCLUDED FRONTAL BOUNDARY MOVES THROUGH THE NORTH
COUNTRY FRIDAY NIGHT. RAIN SHOULD BE FOCUSED MORE ALONG THE FRONT.
SOME QUESTION AS TO HOW MUCH QPF FALLS WITH THE FRONT AND PENDING
HOW MUCH SNOW CAN MELT, COULD HAVE TO KEEP AN EYE ON OUR RIVERS
FOR RISES. THOUGH TEMPERATURES ALOFT COOL BEHIND THE FRONT, RH
PROFILES SUGGEST AT LEAST PARTIAL CLOUDINESS, WHICH KEEPS LOWS
STILL IN THE 30S/AROUND 40.
SATURDAY: SECONDARY COLD FRONT SWEEPS ACROSS THE NORTH COUNTRY
DURING THE DAY SATURDAY. I`VE SHOWN CHANCE POPS ACROSS NORTHERN
ZONES FOR SATURDAY, WITH HIGHS IN THE UPPER 40S/AROUND 50.
SATURDAY NIGHT - SUNDAY: GENERALLY DRY AS HIGH PRESSURE BUILDS IN,
BUT COLD ADVECTION REGIME BRINGS 850 MB TEMPS BACK DOWN TO -4 TO -
6C. CONTINUED DRY WEATHER INTO SUNDAY UNDER SURFACE HIGH PRESSURE.
USED SUPERBLEND GUIDANCE FOR TEMPS THIS PERIOD, WITH LOWS IN THE
UPPER 20S/LOWER 30S SATURDAY NIGHT AND HIGHS UPPER 40S TO MID 50S.
PATTERN THEN GETS A BIT LESS CERTAIN SUNDAY NIGHT INTO MONDAY, BUT
INDICATIONS ARE FOR A RETURN TO MILDER WEATHER FOR EARLY NEXT
WEEK. LARGELY STUCK WITH BLENDED GUIDANCE TO CLOSE THE EXTENDED.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...A MIX OF FLIGHT CATEGORIES BETWEEN VFR TO
IFR AS WARM FRONT LIFTS TO ABOUT THE CANADIAN BORDER, AND SAGS
BACK SOUTHWARD LATER THIS EVENING. PRETTY BUSY TAF PERIOD WITH LOW
VISIBILITIES AND MOUNTAINS OBSCURED BY LOW CEILINGS, BUT OVERALL
LIMITED IMPACT TO AVIATION GROUND OPERATIONS.
COMPOSITE RADAR SHOWS AN EAST-WEST BAND OF ECHOES PRODUCING IFR
VISIBILITY RAIN/SNOW MIX NOW LIFTING NORTHWARD ACROSS THE TAFS.
FURTHER SOUTH THOUGH, PRECIPITATION HAS ALREADY ENDED - AT LEAST
TEMPORARILY AT RUT. VISIBILITIES SHOULD BEGIN TO IMPROVE FROM
SOUTH TO NORTH AS FRONT LIFTS NORTH THROUGH 00Z WEDNESDAY. EXPECT
A BREAK IN PRECIPITATION AND IMPROVEMENT IN VISBYS UNTIL AROUND
00-02Z. APPROACHING MOISTURE FROM THE OHIO VALLEY IS PROGGED BY
THE HRRR TO SHIFT INTO RUT, WHILE WARM FRONT TO THE NORTH BEGINS
ITS SAG SOUTHWARD. THAT SHOULD PRODUCE ANOTHER PERIOD OF MVFR TO
IFR VISIBILITIES IN RAIN/SNOW. WINDS LIGHT/VARIABLE BECOMING
SOUTH UNDER 10 KTS, THEN SHIFTING TO NORTH UNDER 10 KTS OVERNIGHT
AS BOUNDARY SAGS BACK SOUTHWARD.
FOR TUESDAY, ANY LINGERING PRECIPITATION WILL REMAIN PRIMARILY AT
RUT IN THE MORNING HOURS. EXPECT MOSTLY VFR CONDITIONS ELSEWHERE.
OUTLOOK 18Z TUESDAY THROUGH FRIDAY...
18Z TUESDAY THROUGH 18Z WEDNESDAY...TRENDING VFR AT ALL TERMINALS
WITH HIGH PRESSURE BUILDING SOUTH INTO THE AREA.
18Z WEDNESDAY THROUGH 06Z THURSDAY...TRENDING MVFR/OCCNL IFR IN
PERIODS OF LIGHT RAIN/SNOW WITH ADDITIONAL ENERGY RIDING ALONG
SEMI-STATIONARY FRONT ACROSS THE REGION.
06Z THURSDAY THROUGH 00Z FRIDAY...TRENDING VFR WITH HIGH PRESSURE,
THOUGH BKN/OVC CIGS STILL LIKELY.
00Z FRIDAY THROUGH 00Z SATURDAY...IFR/MVFR IN STEADIER RAIN AND
SNOW SHOWERS WITH ADDITIONAL ENERGY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...WGH
NEAR TERM...WGH
SHORT TERM...WGH
LONG TERM...LOCONTO
AVIATION...LOCONTO
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
339 PM EDT MON APR 6 2015
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO BE THE FOCUS FOR NORTH COUNTRY
WEATHER INTO THE MIDDLE PART OF THE WEEK, WITH A MIXTURE OF RAIN
AND WET SNOW. EXPECT BELOW NORMAL HIGHS WITH NEAR NORMAL LOWS.
THOUGH BRIEF DRY WEATHER IS EXPECTED FOR THURSDAY, THE PATTERN
BEGINS TO TURN ACTIVE AGAIN LATER IN THE WEEK.
&&
.NEAR TERM /UNTIL 7 AM TUESDAY MORNING/...
AS OF 143 PM EDT MONDAY...LIGHT SNOW FINALLY REACHING THE SURFACE
ACROSS NORTHERN NEW YORK AND NORTHERN VERMONT AT THIS TIME. WILL
GO WITH LIKELY POPS OVER THE NORTHERN PORTION OF THE FORECAST AREA
FOR THE REST OF TODAY.
&&
.SHORT TERM /7 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 445 AM EDT MONDAY...IT`S AN ACTIVE PERIOD OF WEATHER FOR
THE NORTH COUNTRY, AS WARM FRONT/BAROCLINIC ZONE WILL BE THE
PREDOMINANT PLAYER IN NORTH COUNTRY WEATHER THROUGH MID-WEEK.
THOUGH THE FRONT WILL OSCILLATE NORTH/SOUTH, WEAK MID-LEVEL VORT
MAXIMA ACTING ON THE BOUNDARY WILL RESULT IN LOTS OF CLOUDS AND
SEVERAL PERIODS OF PRECIPITATION. IT`S ALSO WORTH NOTING THAT
PRECIPITATION TYPE WILL BE GOVERNED LARGELY BY TIME OF DAY AND
ELEVATION.
TONIGHT SCATTERED LIGHT RAIN AND SNOW SHOWERS CONTINUE WITH FRONT
STILL DRAPED ACROSS THE AREA...ESPECIALLY SOUTH. TUESDAY WILL BE
THE BEST SHOT AT A DRY PERIOD DURING THE SHORT TERM. THEN TUESDAY
NIGHT AND WEDNESDAY CHANCE FOR PRECIP RETURNS WITH MORE SHORTWAVES
CROSSING OUR FORECAST AREA.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 336 PM EDT MONDAY...12Z GLOBAL SUITE OF GUIDANCE IS IN GOOD
AGREEMENT ON THE EXPECTED PATTERN. FOR MUCH OF THE PERIOD, LARGE-
SCALE MID-/UPPER-LEVEL HEIGHT FALLS REBUILD INTO THE INTERMOUNTAIN
WEST, WHICH LEADS TO DOWNSTREAM UPPER RIDGING ACROSS THE EASTERN
THIRD OF THE COUNTRY. IT APPEARS THAT A PATTERN CHANGE TOWARD
MILDER WEATHER IS IN THE OFFING. IT`S MORE REPRESENTATIVE OF
SPRING THAN WHAT WE`VE EXPERIENCED RECENTLY, AT LEAST.
THURSDAY: LOW-LEVEL WARM ADVECTION/ISENTROPIC ASCENT REGIME WITH
WARMING 1000-500 MB THICKNESSES PRODUCES MAINLY LIGHT RAIN. THE ONE
EXCEPTION WILL BE ACROSS EASTERN VT IN THE MORNING, AS COLD-AIR
DAMMING SIGNATURE EVIDENT IN SEA-LEVEL PRESSURE AND THICKNESS FILEDS
SUGGEST NEAR TO SUB-FREEZING LOW-LEVELS IN THESE AREAS. STRENGTH OF
WARM ADVECTION SHOULD READILY OVERCOME THIS LAYER, THOUGH, SO PERIOD
OF FROZEN PRECIP IS BRIEF. HIGHS LOWER 40S EASTERN VT TO AROUND 50
FOR ST. LAWRENCE VALLEY.
THURSDAY NIGHT: BEST SURGE OF WARM FRONTAL PRECIP COMES IN DURING
THE EARLY PART OF THURSDAY NIGHT. SOUTH WINDS ALSO ON THE
INCREASE, SO WHILE POPS ARE GENERALLY IN THE LIKELY CATEGORY, I DO
SHOW A RELATIVE MIN IN POPS IN THE CHAMPLAIN VALLEY, AS BREEZY SOUTH
WINDS TEND TO LIMIT QPF LOCALLY. ASIDE FROM EASTERN VT WHERE MID
30S ARE FORECAST, LOWS OTHERWISE ARE UPPER 30S TO THE MID 40S
GIVEN ABUNDANCE OF CLOUDS/PRECIP.
FRIDAY: 500 MB RIDGE CONTINUES TO AMPLIFY AHEAD OF A DIGGING
SHORTWAVE INTO THE NORTHERN/CENTRAL PLAINS. WITH MUCH OF THE NORTH
COUNTRY IN A WARM SECTOR BETWEEN APPROACHING OCCLUDED FRONT, WARM
THERMAL AND MOISTURE ADVECTION SHOULD BE UNDERWAY ON FRIDAY. IN
FACT, PWAT VALUES DO CLIMB OVER AN INCH PER THE 12Z GFS. SHOULD SEE
PERIODS OF LIGHT SHOWERS IN THE WARM SECTOR, WITH THE GREATEST POPS
TIED MOSTLY TO THE COLD FRONT. 925/850 MB TEMPS WARM TO AROUND +10C,
THOUGH LIKELY PARTIAL TO MOSTLY CLOUDY SKIES ONLY YIELD HIGHS IN THE
MID TO UPPER 50S. RESULTING SNOW MELT SHOULD PRODUCE SOME RISE IN
RIVER LEVELS, THOUGH CURRENT STAGES STILL ARE PRETTY LOW.
FRIDAY NIGHT: OCCLUDED FRONTAL BOUNDARY MOVES THROUGH THE NORTH
COUNTRY FRIDAY NIGHT. RAIN SHOULD BE FOCUSED MORE ALONG THE FRONT.
SOME QUESTION AS TO HOW MUCH QPF FALLS WITH THE FRONT AND PENDING
HOW MUCH SNOW CAN MELT, COULD HAVE TO KEEP AN EYE ON OUR RIVERS
FOR RISES. THOUGH TEMPERATURES ALOFT COOL BEHIND THE FRONT, RH
PROFILES SUGGEST AT LEAST PARTIAL CLOUDINESS, WHICH KEEPS LOWS
STILL IN THE 30S/AROUND 40.
SATURDAY: SECONDARY COLD FRONT SWEEPS ACROSS THE NORTH COUNTRY
DURING THE DAY SATURDAY. I`VE SHOWN CHANCE POPS ACROSS NORTHERN
ZONES FOR SATURDAY, WITH HIGHS IN THE UPPER 40S/AROUND 50.
SATURDAY NIGHT - SUNDAY: GENERALLY DRY AS HIGH PRESSURE BUILDS IN,
BUT COLD ADVECTION REGIME BRINGS 850 MB TEMPS BACK DOWN TO -4 TO -
6C. CONTINUED DRY WEATHER INTO SUNDAY UNDER SURFACE HIGH PRESSURE.
USED SUPERBLEND GUIDANCE FOR TEMPS THIS PERIOD, WITH LOWS IN THE
UPPER 20S/LOWER 30S SATURDAY NIGHT AND HIGHS UPPER 40S TO MID 50S.
PATTERN THEN GETS A BIT LESS CERTAIN SUNDAY NIGHT INTO MONDAY, BUT
INDICATIONS ARE FOR A RETURN TO MILDER WEATHER FOR EARLY NEXT
WEEK. LARGELY STUCK WITH BLENDED GUIDANCE TO CLOSE THE EXTENDED.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...A MIX OF FLIGHT CATEGORIES BETWEEN VFR TO
IFR AS WARM FRONT LIFTS TO ABOUT THE CANADIAN BORDER, AND SAGS
BACK SOUTHWARD LATER THIS EVENING. PRETTY BUSY TAF PERIOD WITH LOW
VISIBILITIES AND MOUNTAINS OBSCURED BY LOW CEILINGS, BUT OVERALL
LIMITED IMPACT TO AVIATION GROUND OPERATIONS.
COMPOSITE RADAR SHOWS AN EAST-WEST BAND OF ECHOES PRODUCING IFR
VISIBILITY RAIN/SNOW MIX NOW LIFTING NORTHWARD ACROSS THE TAFS.
FURTHER SOUTH THOUGH, PRECIPITATION HAS ALREADY ENDED - AT LEAST
TEMPORARILY AT RUT. VISIBILITIES SHOULD BEGIN TO IMPROVE FROM
SOUTH TO NORTH AS FRONT LIFTS NORTH THROUGH 00Z WEDNESDAY. EXPECT
A BREAK IN PRECIPITATION AND IMPROVEMENT IN VISBYS UNTIL AROUND
00-02Z. APPROACHING MOISTURE FROM THE OHIO VALLEY IS PROGGED BY
THE HRRR TO SHIFT INTO RUT, WHILE WARM FRONT TO THE NORTH BEGINS
ITS SAG SOUTHWARD. THAT SHOULD PRODUCE ANOTHER PERIOD OF MVFR TO
IFR VISIBILITIES IN RAIN/SNOW. WINDS LIGHT/VARIABLE BECOMING
SOUTH UNDER 10 KTS, THEN SHIFTING TO NORTH UNDER 10 KTS OVERNIGHT
AS BOUNDARY SAGS BACK SOUTHWARD.
FOR TUESDAY, ANY LINGERING PRECIPITATION WILL REMAIN PRIMARILY AT
RUT IN THE MORNING HOURS. EXPECT MOSTLY VFR CONDITIONS ELSEWHERE.
OUTLOOK 18Z TUESDAY THROUGH FRIDAY...
18Z TUESDAY THROUGH 18Z WEDNESDAY...TRENDING VFR AT ALL TERMINALS
WITH HIGH PRESSURE BUILDING SOUTH INTO THE AREA.
18Z WEDNESDAY THROUGH 06Z THURSDAY...TRENDING MVFR/OCCNL IFR IN
PERIODS OF LIGHT RAIN/SNOW WITH ADDITIONAL ENERGY RIDING ALONG
SEMI-STATIONARY FRONT ACROSS THE REGION.
06Z THURSDAY THROUGH 00Z FRIDAY...TRENDING VFR WITH HIGH PRESSURE,
THOUGH BKN/OVC CIGS STILL LIKELY.
00Z FRIDAY THROUGH 00Z SATURDAY...IFR/MVFR IN STEADIER RAIN AND
SNOW SHOWERS WITH ADDITIONAL ENERGY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NEILES
NEAR TERM...WGH
SHORT TERM...NEILES
LONG TERM...LOCONTO
AVIATION...LOCONTO
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
143 PM EDT MON APR 6 2015
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO BE THE FOCUS FOR NORTH COUNTRY
WEATHER INTO THE MIDDLE PART OF THE WEEK, WITH A MIXTURE OF RAIN
AND WET SNOW. EXPECT BELOW NORMAL HIGHS WITH NEAR NORMAL LOWS.
THOUGH BRIEF DRY WEATHER IS EXPECTED FOR THURSDAY, THE PATTERN
BEGINS TO TURN ACTIVE AGAIN LATER IN THE WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 143 PM EDT MONDAY...LIGHT SNOW FINALLY REACHING THE SURFACE
ACROSS NORTHERN NEW YORK AND NORTHERN VERMONT AT THIS TIME. WILL
GO WITH LIKELY POPS OVER THE NORTHERN PORTION OF THE FORECAST AREA
FOR THE REST OF TODAY.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY/...
AS OF 445 AM EDT MONDAY...IT`S AN ACTIVE PERIOD OF WEATHER FOR
THE NORTH COUNTRY, AS WARM FRONT/BAROCLINIC ZONE WILL BE THE
PREDOMINANT PLAYER IN NORTH COUNTRY WEATHER THROUGH MID-WEEK.
THOUGH THE FRONT WILL OSCILLATE NORTH/SOUTH, WEAK MID-LEVEL VORT
MAXIMA ACTING ON THE BOUNDARY WILL RESULT IN LOTS OF CLOUDS AND
SEVERAL PERIODS OF PRECIPITATION. IT`S ALSO WORTH NOTING THAT
PRECIPITATION TYPE WILL BE GOVERNED LARGELY BY TIME OF DAY AND
ELEVATION.
TONIGHT SCATTERED LIGHT RAIN AND SNOW SHOWERS CONTINUE WITH FRONT
STILL DRAPED ACROSS THE AREA...ESPECIALLY SOUTH. TUESDAY WILL BE
THE BEST SHOT AT A DRY PERIOD DURING THE SHORT TERM. THEN TUESDAY
NIGHT AND WEDNESDAY CHANCE FOR PRECIP RETURNS WITH MORE SHORTWAVES
CROSSING OUR FORECAST AREA.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 406 AM EDT MONDAY...OVERALL GOOD CONSISTENCY IS MAINTAINED
IN THIS MORNING`S GLOBAL MODELS DURING THE LATE WEEK TIME FRAME
AND A LARGELY PERSISTENCE FORECAST WILL BE MAINTAINED (ALBEIT WITH
A FEW CAVEATS) FROM WEDNESDAY NIGHT ONWARD INTO NEXT WEEKEND. AS
WE BEGIN WEDNESDAY NIGHT, THE SURFACE WAVE WILL BE EXITING QUICKLY
EAST PUSHING THE SFC FRONT FURTHER SOUTH WITH LINGERING LIGHT
RAINS/SNOWS ENDING FAIRLY QUICKLY FROM NORTH TO SOUTH THROUGH THE
NIGHT. SOME LIGHT ELEVATIONAL SNOW ACCUMULATIONS WILL BE POSSIBLE
AS THERMAL PROFILES COOL IN THE BOUNDARY LAYER BUT ANY QPF WOULD
BE ON THE LIGHT SIDE.
MODIFIED CP AIRMASS THEN SETTLES ACROSS THE FORECAST AREA THURSDAY
AS HIGH PRESSURE BUILDS ACROSS EASTERN NEW ENGLAND INTO THE
MARITIMES AND WEDGES THE SURFACE FRONT SOUTHWEST THROUGH THE MID-
ATLANTIC STATES IN THE FORM OF A STRONG BACKDOOR FRONT. TYPICAL
UNDER SUCH SCENARIOS WILL BE FOR OUR AREA TO BE ON THE SOMEWHAT
MILDER WESTERN EDGE OF THIS COOLER AIRMASS AS LIGHT SOUTHERLY RETURN
FLOW BEGINS BY AFTERNOON. AS A RESULT I`VE LEANED CLOSE TO BLENDED
GUIDANCE SHOWING HIGH TEMPS RANGING FROM THE LOWER AND MID 40S EAST
AND UPPER 40S TO LOWER 50S FROM THE CHAMPLAIN VALLEY WEST. PARTLY
CLOUDY SKIES SHOULD BE THE MAIN RULE THROUGH MUCH OF THE DAY, BUT
MID/HIGH CLOUDS WILL BE ON THE INCREASE ACROSS THE WESTERN HALF OF
THE FORECAST AREA BY LATER IN THE DAY HERALDING THE ARRIVAL OF THE
NEXT WEATHER SYSTEM IN THE PIPELINE.
BY THURSDAY NIGHT INTO FRIDAY MODELS IN GOOD AGREEMENT SHOWING A
FAIRLY ROBUST GREAT LAKES CUTTER-LIKE SYSTEM TRACKING THROUGH THE
SAINT LAWRENCE/OTTAWA VALLEYS WITH WIDESPREAD, MAINLY LIGHT TO
MODERATE RAIN EXPECTED. INCREASINGLY STRONG WARM THERMAL ADVECTION
IN THE LOWER TO MID LEVELS, AND IMPRESSIVE PWAT SURGE TO IN EXCESS
OF 1.2 INCHES ALL SPELL A WARMING TREND AS OUR OLD REMNANT POLAR
FRONTAL BOUNDARY PUSHES BACK NORTHEASTWARD THROUGH OUR AREA AS A
WARM FRONT. THIS SYSTEM WILL MARK THE ARRIVAL OF A LONG AWAITED
MAJOR PATTERN CHANGE ACROSS THE NORTHEAST AND WILL ACT TO
REORGANIZE THE MID LEVEL FLOW TO MORE WESTERLY, FINALLY ERADICATING
THE PERSISTENT AND ANOMALOUSLY COOL CP AIRMASS WHICH HAS PLAGUED
OUR REGION FOR MOST OF 2015. WITH THE INCREASINGLY STRONG SOUTHERLY
FLOW LEANED TOWARD THE MILDEST END OF AVAILABLE GUIDANCE THURSDAY
NIGHT KEEPING MIN TEMPERATURES IN THE 30S AND 40S AND OFFERING HIGHS
FRIDAY FROM THE UPPER 40S TO THE MID 50S. BIG BUST POTENTIAL ON
AFTERNOON TEMPERATURES WITH LATE DAY 925 TEMPS RANGING FROM +11 TO
+15 ATOP A FAIRLY STRONG LOW LEVEL INVERSION (AT LEAST THAT`S WHAT
THE MODELS SUGGEST). IF WE CAN MIX DEEPER THAN 1 KFT, THEN HIGHS
SOLIDLY INTO THE 50S AND 60S COULD OCCUR WHICH DOES NOT SEEM
IMPLAUSIBLE AS WE`LL BE ENTERING THE SYSTEM DRY SLOT.
BY FRIDAY NIGHT INTO SATURDAY WE REMAIN IN BROAD SOUTHWESTERLY FLOW
ALOFT AS DAMPENING PARENT H5 TROUGH SWINGS THROUGH THE AREA. CAN`T
COMPLETELY RULE OUT SCATTERED SHOWERS HERE AND THERE, ESPECIALLY
FRIDAY EVENING AS DEEPER WARM ADVECTION DEPARTS EAST, BUT THE
OVERALL IDEA WILL BE FOR COVERAGE OF PCPN TO BECOME LESS WIDESPREAD.
TEMPERATURES REMAIN ON THE MILD SIDE WITH LOWS IN THE 40S AND HIGHS
IN THE 50S. SFC HIGH PRESSURE THEN BUILDS INTO THE REGION BY SUNDAY
WITH MAINLY DRY WEATHER, CLEAR TO PTLY CLOUDY SKIES AND HIGH
TEMPERATURES IN THE 50S TO LOCALLY NEAR 60.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...A MIX OF FLIGHT CATEGORIES BETWEEN VFR TO
IFR AS WARM FRONT LIFTS TO ABOUT THE CANADIAN BORDER, AND SAGS
BACK SOUTHWARD LATER THIS EVENING. PRETTY BUSY TAF PERIOD WITH LOW
VISIBILITIES AND MOUNTAINS OBSCURED BY LOW CEILINGS, BUT OVERALL
LIMITED IMPACT TO AVIATION GROUND OPERATIONS.
COMPOSITE RADAR SHOWS AN EAST-WEST BAND OF ECHOES PRODUCING IFR
VISIBILITY RAIN/SNOW MIX NOW LIFTING NORTHWARD ACROSS THE TAFS.
FURTHER SOUTH THOUGH, PRECIPITATION HAS ALREADY ENDED - AT LEAST
TEMPORARILY AT RUT. VISIBILITIES SHOULD BEGIN TO IMPROVE FROM
SOUTH TO NORTH AS FRONT LIFTS NORTH THROUGH 00Z WEDNESDAY. EXPECT
A BREAK IN PRECIPITATION AND IMPROVEMENT IN VISBYS UNTIL AROUND
00-02Z. APPROACHING MOISTURE FROM THE OHIO VALLEY IS PROGGED BY
THE HRRR TO SHIFT INTO RUT, WHILE WARM FRONT TO THE NORTH BEGINS
ITS SAG SOUTHWARD. THAT SHOULD PRODUCE ANOTHER PERIOD OF MVFR TO
IFR VISIBILITIES IN RAIN/SNOW. WINDS LIGHT/VARIABLE BECOMING
SOUTH UNDER 10 KTS, THEN SHIFTING TO NORTH UNDER 10 KTS OVERNIGHT
AS BOUNDARY SAGS BACK SOUTHWARD.
FOR TUESDAY, ANY LINGERING PRECIPITATION WILL REMAIN PRIMARILY AT
RUT IN THE MORNING HOURS. EXPECT MOSTLY VFR CONDITIONS ELSEWHERE.
OUTLOOK 18Z TUESDAY THROUGH FRIDAY...
18Z TUESDAY THROUGH 18Z WEDNESDAY...TRENDING VFR AT ALL TERMINALS
WITH HIGH PRESSURE BUILDING SOUTH INTO THE AREA.
18Z WEDNESDAY THROUGH 06Z THURSDAY...TRENDING MVFR/OCCNL IFR IN
PERIODS OF LIGHT RAIN/SNOW WITH ADDITIONAL ENERGY RIDING ALONG
SEMI-STATIONARY FRONT ACROSS THE REGION.
06Z THURSDAY THROUGH 00Z FRIDAY...TRENDING VFR WITH HIGH PRESSURE,
THOUGH BKN/OVC CIGS STILL LIKELY.
00Z FRIDAY THROUGH 00Z SATURDAY...IFR/MVFR IN STEADIER RAIN AND
SNOW SHOWERS WITH ADDITIONAL ENERGY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NEILES
NEAR TERM...WGH
SHORT TERM...NEILES
LONG TERM...JMG
AVIATION...JMG/LOCONTO
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
137 PM EDT MON APR 6 2015
.SYNOPSIS...
A WARM FRONT WILL CONTINUE TO BE THE FOCUS FOR NORTH COUNTRY
WEATHER INTO THE MIDDLE PART OF THE WEEK, WITH A MIXTURE OF RAIN
AND WET SNOW. EXPECT BELOW NORMAL HIGHS WITH NEAR NORMAL LOWS.
THOUGH BRIEF DRY WEATHER IS EXPECTED FOR THURSDAY, THE PATTERN
BEGINS TO TURN ACTIVE AGAIN LATER IN THE WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1046 AM EDT MONDAY...COMPOSITE RADAR LOOP SHOWING SOME
RETURNS ACROSS THE REGION AT THIS TIME. HOWEVER...SURFACE
OBSERVATIONS SHOWING NO PRECIPITATION REACHING THE SURFACE AT THIS
TIME...WITH MAINLY A MID LEVEL CLOUD DECK ACROSS THE REGION. GIVEN
CLOUD COVER...HAVE LOWERED MAX TEMPERATURES TODAY 2-5 DEGREES FROM
PREVIOUS FORECAST. HAVE ALSO LOWERED POPS AS WELL TO REFLECT THE
FACT THAT NO PRECIPITATION IS REACHING THE SURFACE AT THIS TIME.
PREVIOUS DISCUSSION FROM 733 AM EDT MONDAY...SURFACE FRONT WILL
LIFT NORTH ACROSS OUR FORECAST AREA TODAY BRINGING SCATTERED RAIN
AND SNOW SHOWERS. LOTS OF CLOUD COVER WILL BE IN PLACE...THOUGH
TEMPS STILL REACH THE UPPER 30S TO MID 40S. PRECIPITATION IS
EXPECTED TO BE LIGHT WITH NOT A LOT OF LOW LEVEL MOISTURE...THOUGH
PRETTY WIDESPREAD ACROSS OUR NORTHERN ZONES ESPECIALLY.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY/...
AS OF 445 AM EDT MONDAY...IT`S AN ACTIVE PERIOD OF WEATHER FOR
THE NORTH COUNTRY, AS WARM FRONT/BAROCLINIC ZONE WILL BE THE
PREDOMINANT PLAYER IN NORTH COUNTRY WEATHER THROUGH MID-WEEK.
THOUGH THE FRONT WILL OSCILLATE NORTH/SOUTH, WEAK MID-LEVEL VORT
MAXIMA ACTING ON THE BOUNDARY WILL RESULT IN LOTS OF CLOUDS AND
SEVERAL PERIODS OF PRECIPITATION. IT`S ALSO WORTH NOTING THAT
PRECIPITATION TYPE WILL BE GOVERNED LARGELY BY TIME OF DAY AND
ELEVATION.
TONIGHT SCATTERED LIGHT RAIN AND SNOW SHOWERS CONTINUE WITH FRONT
STILL DRAPED ACROSS THE AREA...ESPECIALLY SOUTH. TUESDAY WILL BE
THE BEST SHOT AT A DRY PERIOD DURING THE SHORT TERM. THEN TUESDAY
NIGHT AND WEDNESDAY CHANCE FOR PRECIP RETURNS WITH MORE SHORTWAVES
CROSSING OUR FORECAST AREA.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 406 AM EDT MONDAY...OVERALL GOOD CONSISTENCY IS MAINTAINED
IN THIS MORNING`S GLOBAL MODELS DURING THE LATE WEEK TIME FRAME
AND A LARGELY PERSISTENCE FORECAST WILL BE MAINTAINED (ALBEIT WITH
A FEW CAVEATS) FROM WEDNESDAY NIGHT ONWARD INTO NEXT WEEKEND. AS
WE BEGIN WEDNESDAY NIGHT, THE SURFACE WAVE WILL BE EXITING QUICKLY
EAST PUSHING THE SFC FRONT FURTHER SOUTH WITH LINGERING LIGHT
RAINS/SNOWS ENDING FAIRLY QUICKLY FROM NORTH TO SOUTH THROUGH THE
NIGHT. SOME LIGHT ELEVATIONAL SNOW ACCUMULATIONS WILL BE POSSIBLE
AS THERMAL PROFILES COOL IN THE BOUNDARY LAYER BUT ANY QPF WOULD
BE ON THE LIGHT SIDE.
MODIFIED CP AIRMASS THEN SETTLES ACROSS THE FORECAST AREA THURSDAY
AS HIGH PRESSURE BUILDS ACROSS EASTERN NEW ENGLAND INTO THE
MARITIMES AND WEDGES THE SURFACE FRONT SOUTHWEST THROUGH THE MID-
ATLANTIC STATES IN THE FORM OF A STRONG BACKDOOR FRONT. TYPICAL
UNDER SUCH SCENARIOS WILL BE FOR OUR AREA TO BE ON THE SOMEWHAT
MILDER WESTERN EDGE OF THIS COOLER AIRMASS AS LIGHT SOUTHERLY RETURN
FLOW BEGINS BY AFTERNOON. AS A RESULT I`VE LEANED CLOSE TO BLENDED
GUIDANCE SHOWING HIGH TEMPS RANGING FROM THE LOWER AND MID 40S EAST
AND UPPER 40S TO LOWER 50S FROM THE CHAMPLAIN VALLEY WEST. PARTLY
CLOUDY SKIES SHOULD BE THE MAIN RULE THROUGH MUCH OF THE DAY, BUT
MID/HIGH CLOUDS WILL BE ON THE INCREASE ACROSS THE WESTERN HALF OF
THE FORECAST AREA BY LATER IN THE DAY HERALDING THE ARRIVAL OF THE
NEXT WEATHER SYSTEM IN THE PIPELINE.
BY THURSDAY NIGHT INTO FRIDAY MODELS IN GOOD AGREEMENT SHOWING A
FAIRLY ROBUST GREAT LAKES CUTTER-LIKE SYSTEM TRACKING THROUGH THE
SAINT LAWRENCE/OTTAWA VALLEYS WITH WIDESPREAD, MAINLY LIGHT TO
MODERATE RAIN EXPECTED. INCREASINGLY STRONG WARM THERMAL ADVECTION
IN THE LOWER TO MID LEVELS, AND IMPRESSIVE PWAT SURGE TO IN EXCESS
OF 1.2 INCHES ALL SPELL A WARMING TREND AS OUR OLD REMNANT POLAR
FRONTAL BOUNDARY PUSHES BACK NORTHEASTWARD THROUGH OUR AREA AS A
WARM FRONT. THIS SYSTEM WILL MARK THE ARRIVAL OF A LONG AWAITED
MAJOR PATTERN CHANGE ACROSS THE NORTHEAST AND WILL ACT TO
REORGANIZE THE MID LEVEL FLOW TO MORE WESTERLY, FINALLY ERADICATING
THE PERSISTENT AND ANOMALOUSLY COOL CP AIRMASS WHICH HAS PLAGUED
OUR REGION FOR MOST OF 2015. WITH THE INCREASINGLY STRONG SOUTHERLY
FLOW LEANED TOWARD THE MILDEST END OF AVAILABLE GUIDANCE THURSDAY
NIGHT KEEPING MIN TEMPERATURES IN THE 30S AND 40S AND OFFERING HIGHS
FRIDAY FROM THE UPPER 40S TO THE MID 50S. BIG BUST POTENTIAL ON
AFTERNOON TEMPERATURES WITH LATE DAY 925 TEMPS RANGING FROM +11 TO
+15 ATOP A FAIRLY STRONG LOW LEVEL INVERSION (AT LEAST THAT`S WHAT
THE MODELS SUGGEST). IF WE CAN MIX DEEPER THAN 1 KFT, THEN HIGHS
SOLIDLY INTO THE 50S AND 60S COULD OCCUR WHICH DOES NOT SEEM
IMPLAUSIBLE AS WE`LL BE ENTERING THE SYSTEM DRY SLOT.
BY FRIDAY NIGHT INTO SATURDAY WE REMAIN IN BROAD SOUTHWESTERLY FLOW
ALOFT AS DAMPENING PARENT H5 TROUGH SWINGS THROUGH THE AREA. CAN`T
COMPLETELY RULE OUT SCATTERED SHOWERS HERE AND THERE, ESPECIALLY
FRIDAY EVENING AS DEEPER WARM ADVECTION DEPARTS EAST, BUT THE
OVERALL IDEA WILL BE FOR COVERAGE OF PCPN TO BECOME LESS WIDESPREAD.
TEMPERATURES REMAIN ON THE MILD SIDE WITH LOWS IN THE 40S AND HIGHS
IN THE 50S. SFC HIGH PRESSURE THEN BUILDS INTO THE REGION BY SUNDAY
WITH MAINLY DRY WEATHER, CLEAR TO PTLY CLOUDY SKIES AND HIGH
TEMPERATURES IN THE 50S TO LOCALLY NEAR 60.
&&
.AVIATION /17Z MONDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...A MIX OF FLIGHT CATEGORIES BETWEEN VFR TO
IFR AS WARM FRONT LIFTS TO ABOUT THE CANADIAN BORDER, AND SAGS
BACK SOUTHWARD LATER THIS EVENING. PRETTY BUSY TAF PERIOD WITH LOW
VISIBILITIES AND MOUNTAINS OBSCURED BY LOW CEILINGS, BUT OVERALL
LIMITED IMPACT TO AVIATION GROUND OPERATIONS.
COMPOSITE RADAR SHOWS AN EAST-WEST BAND OF ECHOES PRODUCING IFR
VISIBILITY RAIN/SNOW MIX NOW LIFTING NORTHWARD ACROSS THE TAFS.
FURTHER SOUTH THOUGH, PRECIPITATION HAS ALREADY ENDED - AT LEAST
TEMPORARILY AT RUT. VISIBILITIES SHOULD BEGIN TO IMPROVE FROM
SOUTH TO NORTH AS FRONT LIFTS NORTH THROUGH 00Z WEDNESDAY. EXPECT
A BREAK IN PRECIPITATION AND IMPROVEMENT IN VISBYS UNTIL AROUND
00-02Z. APPROACHING MOISTURE FROM THE OHIO VALLEY IS PROGGED BY
THE HRRR TO SHIFT INTO RUT, WHILE WARM FRONT TO THE NORTH BEGINS
ITS SAG SOUTHWARD. THAT SHOULD PRODUCE ANOTHER PERIOD OF MVFR TO
IFR VISIBILITIES IN RAIN/SNOW. WINDS LIGHT/VARIABLE BECOMING
SOUTH UNDER 10 KTS, THEN SHIFTING TO NORTH UNDER 10 KTS OVERNIGHT
AS BOUNDARY SAGS BACK SOUTHWARD.
FOR TUESDAY, ANY LINGERING PRECIPITATION WILL REMAIN PRIMARILY AT
RUT IN THE MORNING HOURS. EXPECT MOSTLY VFR CONDITIONS ELSEWHERE.
OUTLOOK 18Z TUESDAY THROUGH FRIDAY...
18Z TUESDAY THROUGH 18Z WEDNESDAY...TRENDING VFR AT ALL TERMINALS
WITH HIGH PRESSURE BUILDING SOUTH INTO THE AREA.
18Z WEDNESDAY THROUGH 06Z THURSDAY...TRENDING MVFR/OCCNL IFR IN
PERIODS OF LIGHT RAIN/SNOW WITH ADDITIONAL ENERGY RIDING ALONG
SEMI-STATIONARY FRONT ACROSS THE REGION.
06Z THURSDAY THROUGH 00Z FRIDAY...TRENDING VFR WITH HIGH PRESSURE,
THOUGH BKN/OVC CIGS STILL LIKELY.
00Z FRIDAY THROUGH 00Z SATURDAY...IFR/MVFR IN STEADIER RAIN AND
SNOW SHOWERS WITH ADDITIONAL ENERGY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NEILES
NEAR TERM...WGH/NEILES
SHORT TERM...NEILES
LONG TERM...JMG
AVIATION...JMG/LOCONTO
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
406 AM EDT MON APR 6 2015
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTHEAST FROM CENTRAL NEW YORK TONIGHT AND
PRODUCING INCREASING CLOUDS AND CHANCES FOR PRECIPITATION. THE
WARM FRONT WILL CONTINUE TO BE A FOCUS FOR NORTH COUNTRY WEATHER
INTO THE MIDDLE PART OF THE WEEK, WITH A MIXTURE OF RAIN AND WET
SNOW. EXPECT BELOW NORMAL HIGHS WITH NEAR NORMAL LOWS. THOUGH
BRIEF DRY WEATHER IS EXPECTED FOR THURSDAY, THE PATTERN BEGINS TO
TURN ACTIVE AGAIN LATER IN THE WEEK.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 123 AM EDT MONDAY...GOING FORECAST IN PRETTY GOOD SHAPE.
A FEW SCATTERED LIGHT SNOW SHOWERS REMAIN SCATTERED ACROSS PARTS
OF THE NORTHERN TIER. NO MAJOR CHANGES NEEDED.
PREVIOUS DISCUSSION FROM 718 PM SUNDAY...
WEAK MESOSCALE TROUGH IS CURRENTLY SET UP ACROSS NORTHERN NEW
YORK AND DRAPED INTO CENTRAL VERMONT MARKED BY A BREAK IN DEW
POINTS BY ABOUT 5-8 DEGREES AND DIFFERENCE IN WIND DIRECTION
(NORTH VS SOUTHWEST). THIS IS ACTUALLY RESPONSIBLE FOR A
REGENERATION OF CLOUDS AND HAS EVEN TOUCHED OFF A FEW LIGHT SNOW
SHOWERS. LATEST HRRR AND OTHER HI-RES MODELS MAINTAIN THIS WEAK
FEATURE FOR ABOUT THE FIRST OF THE NIGHT BEFORE WASHING IT OUT
OVERNIGHT. THE MAIN FRONTAL ZONE THIS EVENING REMAINS WELL TO THE
SOUTH BY THE NY/PA BORDER. THIS WILL PUSH NORTHWARD OVERNIGHT
SPREADING ADDITIONAL CLOUDS INTO THE REGION AND EVENTUALLY SOME
LIGHT RAIN/SNOW MONDAY MORNING. LOOKING AT LOWS GENERALLY IN THE
20S FOR MOST...WITH A FEW UPPER TEENS POSSIBLE IN THE COLDEST
LOCATIONS OF THE ADIRONDACKS AND NORTHEAST KINGDOM.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH WEDNESDAY/...
AS OF 339 PM EDT SUNDAY...IT`S AN ACTIVE PERIOD OF WEATHER FOR
THE NORTH COUNTRY, AS WARM FRONT/BAROCLINIC ZONE WILL BE THE
PREDOMINANT PLAYER IN NORTH COUNTRY WEATHER THROUGH MID-WEEK.
THOUGH THE FRONT WILL OSCILLATE NORTH/SOUTH, WEAK MID-LEVEL VORT
MAXIMA ACTING ON THE BOUNDARY WILL RESULT IN LOTS OF CLOUDS AND
SEVERAL PERIODS OF PRECIPITATION. IT`S ALSO WORTH NOTING THAT
PRECIPITATION TYPE WILL BE GOVERNED LARGELY BY TIME OF DAY AND
ELEVATION.
SPANNING FROM MIDNIGHT TONIGHT THROUGH EARLY WEDNESDAY, QPF AMOUNTS
RUN FROM A QUARTER INCH FOR THE ST. LAWRENCE VALLEY TO NEAR AN INCH
FOR RUTLAND/WINDSOR COUNTIES. ACROSS THAT SAME TIME PERIOD, SNOW
AMOUNTS IN LOWER ELEVATIONS ARE UNDER 2" (MAINLY ON GRASS), BUT TICK
UPWARD TO 4-6" FOR THE HIGHEST NORTHERN SUMMITS.
DAILY SPECIFICS FOLLOW...
FOR MONDAY: AREAS OF LIGHT SNOW WILL LIKELY BE ONGOING TO BEGIN, BUT
AS SURFACE TEMPERATURES WARM EXPECT WET SNOW TO CHANGE TO RAIN. A
PRETTY WELL-DEFINED WARM-FRONTAL BAND EVIDENT IN MOST AVAILABLE 12Z
GUIDANCE ALLOWS FOR POPS TO INCREASE TO LIKELY/LOW CATEGORICAL INTO
MONDAY AFTERNOON. BLENDED GUIDANCE FOR TEMPS, WITH MORE WEIGHT
TOWARDS COLDER MAV NUMBERS GIVEN OVERCAST. HIGHS IN THE UPPER 30S TO
LOWER/MID 40S.
MONDAY NIGHT: 925-850 TEMPS BEGIN TO RISE ABOVE 0C EARLY MONDAY
NIGHT. HOWEVER, WARMING ALOFT IS FOR A SHORT TIME AS INITIAL FRONTAL
WAVE EXITS INTO NEW HAMPSHIRE. LEFTOVER RAIN BEGINS TO CHANGE OVER
TO A MIX OF RAIN/SNOW OR BRIEFLY AS ICE PELLETS BUT DECREASING POPS
TOWARD TUESDAY MORNING. EXPECT A SLOW FALL IN TEMPERATURES GIVEN
OVERCAST, FALLING TO LOWS AROUND 30 IN AREAS ADJACENT TO THE
CANADIAN BORDER TO THE UPPER 30S FOR SOUTHERN VT.
TUESDAY: NEXT FRONTAL WAVE ON THE LEFTOVER IMPACTS THE NORTH
COUNTRY. HOWEVER, 12Z GUIDANCE SUGGESTS THE BAROCLINIC ZONE GETS
SUPPRESSED A BIT FURTHER TO THE SOUTH THAN ON MONDAY. WITH THE
BOUNDARY BEING SLIGHTLY FURTHER SOUTH, POPS AND QPF ARE HIGHEST FOR
SOUTHERN VT INTO THE ADIRONDACKS AND LOWER FURTHEST NORTH. HIGH
TEMPERATURES ON TUESDAY ARE GENERALLY SIMILAR TO THOSE ON MONDAY.
TUESDAY NIGHT: SECOND FRONTAL WAVE MOVES EASTWARD INTO THE GULF OF
MAINE. POPS TAPER DOWN TO SLIGHT CHANCE/LOW CHANCE FROM NORTHWEST TO
SOUTHEAST DURING THIS PERIOD WITH RAIN CHANGING TO A MIX OF WET SNOW
AS TEMPERATURE/THICKNESS PROFILES COOL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 406 AM EDT MONDAY...OVERALL GOOD CONSISTENCY IS MAINTAINED
IN THIS MORNING`S GLOBAL MODELS DURING THE LATE WEEK TIME FRAME
AND A LARGELY PERSISTENCE FORECAST WILL BE MAINTAINED (ALBEIT WITH
A FEW CAVEATS) FROM WEDNESDAY NIGHT ONWARD INTO NEXT WEEKEND. AS
WE BEGIN WEDNESDAY NIGHT, THE SURFACE WAVE WILL BE EXITING QUICKLY
EAST PUSHING THE SFC FRONT FURTHER SOUTH WITH LINGERING LIGHT
RAINS/SNOWS ENDING FAIRLY QUICKLY FROM NORTH TO SOUTH THROUGH THE
NIGHT. SOME LIGHT ELEVATIONAL SNOW ACCUMULATIONS WILL BE POSSIBLE
AS THERMAL PROFILES COOL IN THE BOUNDARY LAYER BUT ANY QPF WOULD
BE ON THE LIGHT SIDE.
MODIFIED CP AIRMASS THEN SETTLES ACROSS THE FORECAST AREA THURSDAY
AS HIGH PRESSURE BUILDS ACROSS EASTERN NEW ENGLAND INTO THE
MARITIMES AND WEDGES THE SURFACE FRONT SOUTHWEST THROUGH THE MID-
ATLANTIC STATES IN THE FORM OF A STRONG BACKDOOR FRONT. TYPICAL
UNDER SUCH SCENARIOS WILL BE FOR OUR AREA TO BE ON THE SOMEWHAT
MILDER WESTERN EDGE OF THIS COOLER AIRMASS AS LIGHT SOUTHERLY RETURN
FLOW BEGINS BY AFTERNOON. AS A RESULT I`VE LEANED CLOSE TO BLENDED
GUIDANCE SHOWING HIGH TEMPS RANGING FROM THE LOWER AND MID 40S EAST
AND UPPER 40S TO LOWER 50S FROM THE CHAMPLAIN VALLEY WEST. PARTLY
CLOUDY SKIES SHOULD BE THE MAIN RULE THROUGH MUCH OF THE DAY, BUT
MID/HIGH CLOUDS WILL BE ON THE INCREASE ACROSS THE WESTERN HALF OF
THE FORECAST AREA BY LATER IN THE DAY HERALDING THE ARRIVAL OF THE
NEXT WEATHER SYSTEM IN THE PIPELINE.
BY THURSDAY NIGHT INTO FRIDAY MODELS IN GOOD AGREEMENT SHOWING A
FAIRLY ROBUST GREAT LAKES CUTTER-LIKE SYSTEM TRACKING THROUGH THE
SAINT LAWRENCE/OTTAWA VALLEYS WITH WIDESPREAD, MAINLY LIGHT TO
MODERATE RAIN EXPECTED. INCREASINGLY STRONG WARM THERMAL ADVECTION
IN THE LOWER TO MID LEVELS, AND IMPRESSIVE PWAT SURGE TO IN EXCESS
OF 1.2 INCHES ALL SPELL A WARMING TREND AS OUR OLD REMNANT POLAR
FRONTAL BOUNDARY PUSHES BACK NORTHEASTWARD THROUGH OUR AREA AS A
WARM FRONT. THIS SYSTEM WILL MARK THE ARRIVAL OF A LONG AWAITED
MAJOR PATTERN CHANGE ACROSS THE NORTHEAST AND WILL ACT TO
REORGANIZE THE MID LEVEL FLOW TO MORE WESTERLY, FINALLY ERADICATING
THE PERSISTENT AND ANOMALOUSLY COOL CP AIRMASS WHICH HAS PLAGUED
OUR REGION FOR MOST OF 2015. WITH THE INCREASINGLY STRONG SOUTHERLY
FLOW LEANED TOWARD THE MILDEST END OF AVAILABLE GUIDANCE THURSDAY
NIGHT KEEPING MIN TEMPERATURES IN THE 30S AND 40S AND OFFERING HIGHS
FRIDAY FROM THE UPPER 40S TO THE MID 50S. BIG BUST POTENTIAL ON
AFTERNOON TEMPERATURES WITH LATE DAY 925 TEMPS RANGING FROM +11 TO
+15 ATOP A FAIRLY STRONG LOW LEVEL INVERSION (AT LEAST THAT`S WHAT
THE MODELS SUGGEST). IF WE CAN MIX DEEPER THAN 1 KFT, THEN HIGHS
SOLIDLY INTO THE 50S AND 60S COULD OCCUR WHICH DOES NOT SEEM
IMPLAUSIBLE AS WE`LL BE ENTERING THE SYSTEM DRY SLOT.
BY FRIDAY NIGHT INTO SATURDAY WE REMAIN IN BROAD SOUTHWESTERLY FLOW
ALOFT AS DAMPENING PARENT H5 TROUGH SWINGS THROUGH THE AREA. CAN`T
COMPLETELY RULE OUT SCATTERED SHOWERS HERE AND THERE, ESPECIALLY
FRIDAY EVENING AS DEEPER WARM ADVECTION DEPARTS EAST, BUT THE
OVERALL IDEA WILL BE FOR COVERAGE OF PCPN TO BECOME LESS WIDESPREAD.
TEMPERATURES REMAIN ON THE MILD SIDE WITH LOWS IN THE 40S AND HIGHS
IN THE 50S. SFC HIGH PRESSURE THEN BUILDS INTO THE REGION BY SUNDAY
WITH MAINLY DRY WEATHER, CLEAR TO PTLY CLOUDY SKIES AND HIGH
TEMPERATURES IN THE 50S TO LOCALLY NEAR 60.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
THROUGH 06 TUESDAY...MIX OF BKN/OVC VFR/MVFR CIGS THROUGH MUCH OF
THE PERIOD AS FRONTAL BOUNDARY LIFTS SLOWLY NORTH INTO THE REGION
ALONG WITH WIDESPREAD LIGHT PCPN AFTER 14Z. WINDS LIGHT AND
VARIABLE LESS THAN 10 KTS THROUGH THE FORECAST PERIOD. AREAS OF
LIGHT RAIN/LIGHT SNOW TO OVERSPREAD THE REGION FROM SOUTH TO NORTH
DURING THE 13-18Z TIME FRAME AND CONTINUING ON AND OFF THROUGH THE
END OF THE FORECAST PERIOD AS CIGS GRADUALLY LOWER. SOME IFR
POSSIBLE AT KSLK.
OUTLOOK 06Z TUESDAY THROUGH FRIDAY...
06Z TUESDAY THROUGH 12Z THURSDAY...BKN/OVC MVFR/VFR WITH PERIODIC
BOUTS OF MVFR/IFR RAIN AND SNOW SHOWERS AS FRONTAL SYSTEM REMAINS
JUST SOUTH THE AREA WITH WAVES OF LOW PRESSURE RIDING ALONG THE
FRONT.
12Z THURSDAY THROUGH 00Z FRIDAY...VFR AS A RIDGE OF HIGH PRESSURE
WILL BE OVER THE REGION.
00Z FRIDAY THROUGH 00Z SATURDAY...IFR/MVFR IN RAIN AND SNOW
SHOWERS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LOCONTO
NEAR TERM...NEILES/MUCCILLI
SHORT TERM...LOCONTO
LONG TERM...JMG
AVIATION...BANACOS/JMG
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
124 AM EDT MON APR 6 2015
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTHEAST FROM CENTRAL NEW YORK TONIGHT AND
PRODUCING INCREASING CLOUDS AND CHANCES FOR PRECIPITATION. THE
WARM FRONT WILL CONTINUE TO BE A FOCUS FOR NORTH COUNTRY WEATHER
INTO THE MIDDLE PART OF THE WEEK, WITH A MIXTURE OF RAIN AND WET
SNOW. EXPECT BELOW NORMAL HIGHS WITH NEAR NORMAL LOWS. THOUGH
BRIEF DRY WEATHER IS EXPECTED FOR THURSDAY, THE PATTERN BEGINS TO
TURN ACTIVE AGAIN LATER IN THE WEEK.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 123 AM EDT MONDAY...GOING FORECAST IN PRETTY GOOD SHAPE.
A FEW SCATTERED LIGHT SNOW SHOWERS REMAIN SCATTERED ACROSS PARTS
OF THE NORTHERN TIER. NO MAJOR CHANGES NEEDED.
PREVIOUS DISCUSSION FROM 718 PM SUNDAY...
WEAK MESOSCALE TROUGH IS CURRENTLY SET UP ACROSS NORTHERN NEW
YORK AND DRAPED INTO CENTRAL VERMONT MARKED BY A BREAK IN DEW
POINTS BY ABOUT 5-8 DEGREES AND DIFFERENCE IN WIND DIRECTION
(NORTH VS SOUTHWEST). THIS IS ACTUALLY RESPONSIBLE FOR A
REGENERATION OF CLOUDS AND HAS EVEN TOUCHED OFF A FEW LIGHT SNOW
SHOWERS. LATEST HRRR AND OTHER HI-RES MODELS MAINTAIN THIS WEAK
FEATURE FOR ABOUT THE FIRST OF THE NIGHT BEFORE WASHING IT OUT
OVERNIGHT. THE MAIN FRONTAL ZONE THIS EVENING REMAINS WELL TO THE
SOUTH BY THE NY/PA BORDER. THIS WILL PUSH NORTHWARD OVERNIGHT
SPREADING ADDITIONAL CLOUDS INTO THE REGION AND EVENTUALLY SOME
LIGHT RAIN/SNOW MONDAY MORNING. LOOKING AT LOWS GENERALLY IN THE
20S FOR MOST...WITH A FEW UPPER TEENS POSSIBLE IN THE COLDEST
LOCATIONS OF THE ADIRONDACKS AND NORTHEAST KINGDOM.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH TUESDAY NIGHT/...
AS OF 339 PM EDT SUNDAY...IT`S AN ACTIVE PERIOD OF WEATHER FOR
THE NORTH COUNTRY, AS WARM FRONT/BAROCLINIC ZONE WILL BE THE
PREDOMINANT PLAYER IN NORTH COUNTRY WEATHER THROUGH MID-WEEK.
THOUGH THE FRONT WILL OSCILLATE NORTH/SOUTH, WEAK MID-LEVEL VORT
MAXIMA ACTING ON THE BOUNDARY WILL RESULT IN LOTS OF CLOUDS AND
SEVERAL PERIODS OF PRECIPITATION. IT`S ALSO WORTH NOTING THAT
PRECIPITATION TYPE WILL BE GOVERNED LARGELY BY TIME OF DAY AND
ELEVATION.
SPANNING FROM MIDNIGHT TONIGHT THROUGH EARLY WEDNESDAY, QPF AMOUNTS
RUN FROM A QUARTER INCH FOR THE ST. LAWRENCE VALLEY TO NEAR AN INCH
FOR RUTLAND/WINDSOR COUNTIES. ACROSS THAT SAME TIME PERIOD, SNOW
AMOUNTS IN LOWER ELEVATIONS ARE UNDER 2" (MAINLY ON GRASS), BUT TICK
UPWARD TO 4-6" FOR THE HIGHEST NORTHERN SUMMITS.
DAILY SPECIFICS FOLLOW...
FOR MONDAY: AREAS OF LIGHT SNOW WILL LIKELY BE ONGOING TO BEGIN, BUT
AS SURFACE TEMPERATURES WARM EXPECT WET SNOW TO CHANGE TO RAIN. A
PRETTY WELL-DEFINED WARM-FRONTAL BAND EVIDENT IN MOST AVAILABLE 12Z
GUIDANCE ALLOWS FOR POPS TO INCREASE TO LIKELY/LOW CATEGORICAL INTO
MONDAY AFTERNOON. BLENDED GUIDANCE FOR TEMPS, WITH MORE WEIGHT
TOWARDS COLDER MAV NUMBERS GIVEN OVERCAST. HIGHS IN THE UPPER 30S TO
LOWER/MID 40S.
MONDAY NIGHT: 925-850 TEMPS BEGIN TO RISE ABOVE 0C EARLY MONDAY
NIGHT. HOWEVER, WARMING ALOFT IS FOR A SHORT TIME AS INITIAL FRONTAL
WAVE EXITS INTO NEW HAMPSHIRE. LEFTOVER RAIN BEGINS TO CHANGE OVER
TO A MIX OF RAIN/SNOW OR BRIEFLY AS ICE PELLETS BUT DECREASING POPS
TOWARD TUESDAY MORNING. EXPECT A SLOW FALL IN TEMPERATURES GIVEN
OVERCAST, FALLING TO LOWS AROUND 30 IN AREAS ADJACENT TO THE
CANADIAN BORDER TO THE UPPER 30S FOR SOUTHERN VT.
TUESDAY: NEXT FRONTAL WAVE ON THE LEFTOVER IMPACTS THE NORTH
COUNTRY. HOWEVER, 12Z GUIDANCE SUGGESTS THE BAROCLINIC ZONE GETS
SUPPRESSED A BIT FURTHER TO THE SOUTH THAN ON MONDAY. WITH THE
BOUNDARY BEING SLIGHTLY FURTHER SOUTH, POPS AND QPF ARE HIGHEST FOR
SOUTHERN VT INTO THE ADIRONDACKS AND LOWER FURTHEST NORTH. HIGH
TEMPERATURES ON TUESDAY ARE GENERALLY SIMILAR TO THOSE ON MONDAY.
TUESDAY NIGHT: SECOND FRONTAL WAVE MOVES EASTWARD INTO THE GULF OF
MAINE. POPS TAPER DOWN TO SLIGHT CHANCE/LOW CHANCE FROM NORTHWEST TO
SOUTHEAST DURING THIS PERIOD WITH RAIN CHANGING TO A MIX OF WET SNOW
AS TEMPERATURE/THICKNESS PROFILES COOL.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 352 PM EDT SUNDAY...ECMWF AND GFS MODELS SHOWING AN
INVERTED SURFACE TROUGH WILL SET UP ACROSS NORTHERN NEW YORK AND
EXTEND SOUTHWEST TO WESTERN PENNSYLVANIA ON WEDNESDAY. THIS WILL
BRING IN RAIN AND SNOW SHOWERS INTO THE REGION BY LATER IN THE DAY
ON WEDNESDAY AND THEN EXTENDING INTO THE FIRST PART OF WEDNESDAY
NIGHT. MODELS SHOWING A RIDGE OF HIGH PRESSURE WILL BUILD
SOUTHWEST FROM NORTHERN MAINE AND THE CANADIAN MARITIMES LATE
WEDNESDAY NIGHT INTO THURSDAY ACROSS THE REGION...SO HAVE GONE
WITH A DRY FORECAST LATE WEDNESDAY NIGHT AND THURSDAY.
ECMWF AND GFS MODELS SHOWING A FRONTAL SYSTEM SOUTHWEST OF THE
REGION EARLY THURSDAY NIGHT WILL BEGIN TO MOVE NORTHEAST AS A WARM
FRONT ON THURSDAY NIGHT AND FRIDAY...AS THE HIGH PRESSURE AREA OVER
THE CANADIAN MARITIMES EARLY THURSDAY NIGHT SLIDES EASTWARD.
EXPECTING A PROLONGED PERIOD OF RAIN AND SNOW SHOWERS FROM THURSDAY
NIGHT INTO SATURDAY AS THE FRONTAL SYSTEM WILL LINGER ACROSS THE
REGION WITH WAVES OF LOW PRESSURE MOVING ALONG THE FRONTAL BOUNDARY.
HAVE KEPT IN A CHANCE OF RAIN AND SNOW SHOWERS ON SUNDAY AS AN UPPER
TROUGH AND CLOSED UPPER LOW MOVES INTO THE REGION.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
THROUGH 06 TUESDAY...MIX OF BKN/OVC VFR/MVFR CIGS THROUGH MUCH OF
THE PERIOD AS FRONTAL BOUNDARY LIFTS SLOWLY NORTH INTO THE REGION
ALONG WITH WIDESPREAD LIGHT PCPN AFTER 14Z. WINDS LIGHT AND
VARIABLE LESS THAN 10 KTS THROUGH THE FORECAST PERIOD. AREAS OF
LIGHT RAIN/LIGHT SNOW TO OVERSPREAD THE REGION FROM SOUTH TO NORTH
DURING THE 13-18Z TIME FRAME AND CONTINUING ON AND OFF THROUGH THE
END OF THE FORECAST PERIOD AS CIGS GRADUALLY LOWER. SOME IFR
POSSIBLE AT KSLK.
OUTLOOK 06Z TUESDAY THROUGH FRIDAY...
06Z TUESDAY THROUGH 12Z THURSDAY...BKN/OVC MVFR/VFR WITH PERIODIC
BOUTS OF MVFR/IFR RAIN AND SNOW SHOWERS AS FRONTAL SYSTEM REMAINS
JUST SOUTH THE AREA WITH WAVES OF LOW PRESSURE RIDING ALONG THE
FRONT.
12Z THURSDAY THROUGH 00Z FRIDAY...VFR AS A RIDGE OF HIGH PRESSURE
WILL BE OVER THE REGION.
00Z FRIDAY THROUGH 00Z SATURDAY...IFR/MVFR IN RAIN AND SNOW
SHOWERS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LOCONTO
NEAR TERM...NEILES/MUCCILLI
SHORT TERM...LOCONTO
LONG TERM...WGH
AVIATION...BANACOS/JMG
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
116 AM EDT MON APR 6 2015
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTHEAST FROM CENTRAL NEW YORK TONIGHT AND
PRODUCING INCREASING CLOUDS AND CHANCES FOR PRECIPITATION. THE
WARM FRONT WILL CONTINUE TO BE A FOCUS FOR NORTH COUNTRY WEATHER
INTO THE MIDDLE PART OF THE WEEK, WITH A MIXTURE OF RAIN AND WET
SNOW. EXPECT BELOW NORMAL HIGHS WITH NEAR NORMAL LOWS. THOUGH
BRIEF DRY WEATHER IS EXPECTED FOR THURSDAY, THE PATTERN BEGINS TO
TURN ACTIVE AGAIN LATER IN THE WEEK.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1002 PM EDT SUNDAY...GOING FORECAST IN PRETTY GOOD SHAPE.
A FEW SCATTERED LIGHT SNOW SHOWERS REMAIN SCATTERED ACROSS PARTS
OF THE NORTHERN TIER. NO MAJOR CHANGES NEEDED.
PREVIOUS DISCUSSION FROM 718 PM SUNDAY...
WEAK MESOSCALE TROUGH IS CURRENTLY SET UP ACROSS NORTHERN NEW
YORK AND DRAPED INTO CENTRAL VERMONT MARKED BY A BREAK IN DEW
POINTS BY ABOUT 5-8 DEGREES AND DIFFERENCE IN WIND DIRECTION
(NORTH VS SOUTHWEST). THIS IS ACTUALLY RESPONSIBLE FOR A
REGENERATION OF CLOUDS AND HAS EVEN TOUCHED OFF A FEW LIGHT SNOW
SHOWERS. LATEST HRRR AND OTHER HI-RES MODELS MAINTAIN THIS WEAK
FEATURE FOR ABOUT THE FIRST OF THE NIGHT BEFORE WASHING IT OUT
OVERNIGHT. THE MAIN FRONTAL ZONE THIS EVENING REMAINS WELL TO THE
SOUTH BY THE NY/PA BORDER. THIS WILL PUSH NORTHWARD OVERNIGHT
SPREADING ADDITIONAL CLOUDS INTO THE REGION AND EVENTUALLY SOME
LIGHT RAIN/SNOW MONDAY MORNING. LOOKING AT LOWS GENERALLY IN THE
20S FOR MOST...WITH A FEW UPPER TEENS POSSIBLE IN THE COLDEST
LOCATIONS OF THE ADIRONDACKS AND NORTHEAST KINGDOM.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH TUESDAY NIGHT/...
AS OF 339 PM EDT SUNDAY...IT`S AN ACTIVE PERIOD OF WEATHER FOR
THE NORTH COUNTRY, AS WARM FRONT/BAROCLINIC ZONE WILL BE THE
PREDOMINANT PLAYER IN NORTH COUNTRY WEATHER THROUGH MID-WEEK.
THOUGH THE FRONT WILL OSCILLATE NORTH/SOUTH, WEAK MID-LEVEL VORT
MAXIMA ACTING ON THE BOUNDARY WILL RESULT IN LOTS OF CLOUDS AND
SEVERAL PERIODS OF PRECIPITATION. IT`S ALSO WORTH NOTING THAT
PRECIPITATION TYPE WILL BE GOVERNED LARGELY BY TIME OF DAY AND
ELEVATION.
SPANNING FROM MIDNIGHT TONIGHT THROUGH EARLY WEDNESDAY, QPF AMOUNTS
RUN FROM A QUARTER INCH FOR THE ST. LAWRENCE VALLEY TO NEAR AN INCH
FOR RUTLAND/WINDSOR COUNTIES. ACROSS THAT SAME TIME PERIOD, SNOW
AMOUNTS IN LOWER ELEVATIONS ARE UNDER 2" (MAINLY ON GRASS), BUT TICK
UPWARD TO 4-6" FOR THE HIGHEST NORTHERN SUMMITS.
DAILY SPECIFICS FOLLOW...
FOR MONDAY: AREAS OF LIGHT SNOW WILL LIKELY BE ONGOING TO BEGIN, BUT
AS SURFACE TEMPERATURES WARM EXPECT WET SNOW TO CHANGE TO RAIN. A
PRETTY WELL-DEFINED WARM-FRONTAL BAND EVIDENT IN MOST AVAILABLE 12Z
GUIDANCE ALLOWS FOR POPS TO INCREASE TO LIKELY/LOW CATEGORICAL INTO
MONDAY AFTERNOON. BLENDED GUIDANCE FOR TEMPS, WITH MORE WEIGHT
TOWARDS COLDER MAV NUMBERS GIVEN OVERCAST. HIGHS IN THE UPPER 30S TO
LOWER/MID 40S.
MONDAY NIGHT: 925-850 TEMPS BEGIN TO RISE ABOVE 0C EARLY MONDAY
NIGHT. HOWEVER, WARMING ALOFT IS FOR A SHORT TIME AS INITIAL FRONTAL
WAVE EXITS INTO NEW HAMPSHIRE. LEFTOVER RAIN BEGINS TO CHANGE OVER
TO A MIX OF RAIN/SNOW OR BRIEFLY AS ICE PELLETS BUT DECREASING POPS
TOWARD TUESDAY MORNING. EXPECT A SLOW FALL IN TEMPERATURES GIVEN
OVERCAST, FALLING TO LOWS AROUND 30 IN AREAS ADJACENT TO THE
CANADIAN BORDER TO THE UPPER 30S FOR SOUTHERN VT.
TUESDAY: NEXT FRONTAL WAVE ON THE LEFTOVER IMPACTS THE NORTH
COUNTRY. HOWEVER, 12Z GUIDANCE SUGGESTS THE BAROCLINIC ZONE GETS
SUPPRESSED A BIT FURTHER TO THE SOUTH THAN ON MONDAY. WITH THE
BOUNDARY BEING SLIGHTLY FURTHER SOUTH, POPS AND QPF ARE HIGHEST FOR
SOUTHERN VT INTO THE ADIRONDACKS AND LOWER FURTHEST NORTH. HIGH
TEMPERATURES ON TUESDAY ARE GENERALLY SIMILAR TO THOSE ON MONDAY.
TUESDAY NIGHT: SECOND FRONTAL WAVE MOVES EASTWARD INTO THE GULF OF
MAINE. POPS TAPER DOWN TO SLIGHT CHANCE/LOW CHANCE FROM NORTHWEST TO
SOUTHEAST DURING THIS PERIOD WITH RAIN CHANGING TO A MIX OF WET SNOW
AS TEMPERATURE/THICKNESS PROFILES COOL.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 352 PM EDT SUNDAY...ECMWF AND GFS MODELS SHOWING AN
INVERTED SURFACE TROUGH WILL SET UP ACROSS NORTHERN NEW YORK AND
EXTEND SOUTHWEST TO WESTERN PENNSYLVANIA ON WEDNESDAY. THIS WILL
BRING IN RAIN AND SNOW SHOWERS INTO THE REGION BY LATER IN THE DAY
ON WEDNESDAY AND THEN EXTENDING INTO THE FIRST PART OF WEDNESDAY
NIGHT. MODELS SHOWING A RIDGE OF HIGH PRESSURE WILL BUILD
SOUTHWEST FROM NORTHERN MAINE AND THE CANADIAN MARITIMES LATE
WEDNESDAY NIGHT INTO THURSDAY ACROSS THE REGION...SO HAVE GONE
WITH A DRY FORECAST LATE WEDNESDAY NIGHT AND THURSDAY.
ECMWF AND GFS MODELS SHOWING A FRONTAL SYSTEM SOUTHWEST OF THE
REGION EARLY THURSDAY NIGHT WILL BEGIN TO MOVE NORTHEAST AS A WARM
FRONT ON THURSDAY NIGHT AND FRIDAY...AS THE HIGH PRESSURE AREA OVER
THE CANADIAN MARITIMES EARLY THURSDAY NIGHT SLIDES EASTWARD.
EXPECTING A PROLONGED PERIOD OF RAIN AND SNOW SHOWERS FROM THURSDAY
NIGHT INTO SATURDAY AS THE FRONTAL SYSTEM WILL LINGER ACROSS THE
REGION WITH WAVES OF LOW PRESSURE MOVING ALONG THE FRONTAL BOUNDARY.
HAVE KEPT IN A CHANCE OF RAIN AND SNOW SHOWERS ON SUNDAY AS AN UPPER
TROUGH AND CLOSED UPPER LOW MOVES INTO THE REGION.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
THROUGH 06 TUESDAY...MIX OF BKN/OVC VFR/MVFR CIGS THROUGH MUCH OF
THE PERIOD AS FRONTAL BOUNDARY LIFTS SLOWLY NORTH INTO THE REGION
ALONG WITH WIDESPREAD LIGHT PCPN AFTER 14Z. WINDS LIGHT AND
VARIABLE LESS THAN 10 KTS THROUGH THE FORECAST PERIOD. AREAS OF
LIGHT RAIN/LIGHT SNOW TO OVERSPREAD THE REGION FROM SOUTH TO NORTH
DURING THE 13-18Z TIME FRAME AND CONTINUING ON AND OFF THROUGH THE
END OF THE FORECAST PERIOD AS CIGS GRADUALLY LOWER. SOME IFR
POSSIBLE AT KSLK.
OUTLOOK 06Z TUESDAY THROUGH FRIDAY...
06Z TUESDAY THROUGH 12Z THURSDAY...BKN/OVC MVFR/VFR WITH PERIODIC
BOUTS OF MVFR/IFR RAIN AND SNOW SHOWERS AS FRONTAL SYSTEM REMAINS
JUST SOUTH THE AREA WITH WAVES OF LOW PRESSURE RIDING ALONG THE
FRONT.
12Z THURSDAY THROUGH 00Z FRIDAY...VFR AS A RIDGE OF HIGH PRESSURE
WILL BE OVER THE REGION.
00Z FRIDAY THROUGH 00Z SATURDAY...IFR/MVFR IN RAIN AND SNOW
SHOWERS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LOCONTO
NEAR TERM...MUCCILLI
SHORT TERM...LOCONTO
LONG TERM...WGH
AVIATION...BANACOS/JMG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
946 PM CDT TUE APR 7 2015
.UPDATE...
ISSUED AT 945 PM CDT TUE APR 7 2015
PRECIP CURRENTLY STRETCHING FROM LAKE OF THE WOODS DOWN IN A
NARROWING BAND TOWARDS FARGO. THE PRECIP SHOULD CONTINUE TO PUSH
EASTWARD AS A RAIN/SNOW MIX AND ADJUSTED GRIDS TO REFLECT THE
RADAR TRENDS AND RAP/HRRR WHICH SEEM TO HAVE A GOOD HANDLE ON THE
PRECIP. THE 21Z SREF HAS BACKED OFF ON THE VERY HIGH PROBABILITIES
OF LOW VISIBILITY IN THE NORTHWESTERN COUNTIES...BUT THE RAP AND
HRRR STILL HAVE SOME FOG FORMATION. A FEW SPOTS IN THE JAMES AND
SHEYENNE VALLEYS HAVE SEEN DROPS IN VISIBILITY SO WILL KEEP THE
PATCHY/AREAS OF FOG FORMATION FOR NOW BUT AT THIS POINT DO NOT
THINK WE WILL GET A LOT OF SUPER DENSE FOG.
UPDATE ISSUED AT 652 PM CDT TUE APR 7 2015
TWEAKED POPS FOR CURRENT RADAR TRENDS...THINK THAT THE PRECIP
SHOULD CONTINUE TO MOVE EASTWARD THROUGH THE RED RIVER VALLEY AND
WILL BE MOSTLY IN WESTERN MINNESOTA BY LATE EVENING. REPORTS HAVE
1 TO 2 INCHES MAINLY IN THE NORTHERN COUNTIES...SO WILL KEEP THE
1-3 INCH ACCUMULATIONS NORTH OF HIGHWAY 2 THAT WE HAVE GOING. SREF
PROBABILITIES AND HRRR VIS SHOW SOME FOG IN THE DEVILS LAKE BASIN
TOWARDS MORNING. BUMPED UP MENTION TO AREAS OF FOG AND WILL KEEP
AN EYE ON DENSITY FOR NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 300 PM CDT TUE APR 7 2015
CHALLENGES CENTER AROUND PRECIP AND PRECIP TYPE THROUGH THU...THEN
TEMPS. MODELS ARE IN PRETTY GOOD OVERALL AGREEMENT THROUGH
FRIDAY...LEADING TO SOME INCREASED CONFIDENCE IN THIS FORECAST.
FOR THE REST OF THIS AFTERNOON AND OVERNIGHT...THE BAND OF PRECIP
WILL SLOWLY SHIFT FROM WEST TO EAST. THERE IS STRONG OMEGA/WAA IN
THE MID LEVELS THAT SHOULD TARGET AREAS ALONG AND NORTH OF US
HIGHWAY 2 THROUGH 6Z. EXPECT MOST SNOW IN THE FAR NORTH WITH A MIX
OF RAIN/SNOW POSSIBLE FURTHER SOUTH AND PROBABLY JUST RAIN IN THE
SOUTH. THERE COULD BE AN INCH OR 2 OF SNOW IN THE NORTH THROUGH
THE OVERNIGHT...WITH SOME SLICK SPOTS IF SNOW RATES BECOME HIGH
ENOUGH AND AFTER DARK. TEMPS WON/T FALL TOO MUCH OVERNIGHT GIVEN
THE POTENTIAL OF LOW CLOUDS AND EVEN SOME PATCHY FOG LATE IN THE
WEST. FOR NOW WON/T MENTION FOG...BUT POTENTIAL WILL HAVE TO BE MONITORED.
FOR WED...IT SHOULD BE DRY FOR MOST OF THE DAY...WITH THE THREAT
FOR SOME LIGHT PRECIP MOVING INTO THE WEST AND SOUTH TOWARDS 00Z
THU. TEMPS SHOULD WARM A BIT FROM TODAY...AND HINGE LARGELY ON IF
THERE IS ANY SUNSHINE.
FOR WED NIGHT...THE COLUMN WILL SATURATE AS A LARGE STORM SYSTEM
MOVES INTO THE CENTRAL PLAINS. EXPECT SOME RAIN INITIALLY IN THE
SOUTH WITH PRECIP POSSIBLY MIXING WITH SOME SNOW FURTHER NORTH
OVERNIGHT. NOT EXPECTING HEAVY PRECIP RATES WITH THIS SYSTEM...SO
LITTLE IF ANY SNOW ACCUMS EXPECTED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 300 PM CDT TUE APR 7 2015
FOR THURSDAY...ANY PRECIP SHOULD MOVE OUT OF THE SOUTHEAST FA BY
18Z. TEMPS WILL WARM A BIT FROM WED WITH SOME SUNSHINE EXPECTED.
ON FRIDAY...ANOTHER DRY DAY IS EXPECTED WITH TEMPS SIMILAR TO THU.
THERE WILL BE SOME COOL AIR ALOFT IN THE FAR NORTHEAST...AND CAN/T
RULE OUT A SPRINKLE...BUT FOR NOW WILL KEEP IT DRY.
FOR FRIDAY NIGHT THROUGH TUESDAY...WILL START OFF THE PERIOD WITH
RIDGING AT 500MB AND THUS MILD TEMPS FOR SAT/SUN. THE 12Z GFS SHOWS
A LITTLE PREFRONTAL PCPN ACROSS THE FA AS EARLY AS SATURDAY
AFTERNOON...WHILE THE OTHER MODELS ARE DRY. THINK PCPN CHANCES WILL
INCREASE AS A COLD FRONT MOVES THRU SUNDAY/SUN NIGHT. SHOULD STILL
BE WARM ENOUGH THAT THIS PCPN WILL FALL AS RAIN. MORE UNCERTAINTY
ENTERS THE FORECAST BY MON INTO TUE WITH THE 12Z GFS ESSENTIALLY
DRY. ECMWF SHOWS A LITTLE LIGHT PCPN BUT CONFIDENCE PRETTY LOW AT
THIS POINT. WILL KEEP THE LOW GUIDANCE PCPN CHANCES ON MONDAY BUT
THINK THAT MAY BE OVERDONE. SHOULD BE A LITTLE COOLER MON/TUE BEHIND
THE COLD FRONT BUT TEMPS STILL LOOK TO BE WARMER THAN NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 652 PM CDT TUE APR 7 2015
PRECIP CONTINUES TO MOVE EASTWARD ACROSS THE AREA. IT HAS ENDED IN
KDVL FOR THE NIGHT AND JUST STARTED IN KBJI. THINK THAT THE SITES
ALONG THE RED RIVER WILL SEE -SN/-RA ENDING IN THE NEXT FEW HOURS
WHILE THERE WILL BE SOME LIGHT SNOW A BIT LONGER FURTHER EAST
BEFORE ALL PRECIP ENDS AFTER 06Z. THE SREF HAS HIGH PROBABILITIES
OF VIS LESS THAN 1SM IN THE KDVL AREA TOWARDS MORNING. THINK THAT
LOW CLOUDS WILL BE PROBABLE AND WITH RECENT PRECIP FOG IS
POSSIBLE. JUST INCLUDED 1SM FOR NOW AND WILL TAKE A LOOK IF WE
NEED ANYTHING LOWER AS THE EVENING WEARS ON. AT KGFK AND KFAR KEPT
VIS IN THE MVFR CATEGORY BUT HAVE CIGS BELOW 1000 FT. THINK THAT
MOST SITES SHOULD BE UP TO MVFR BY MID MORNING TOMORROW.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...DK
LONG TERM...GODON/DK
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
652 PM CDT TUE APR 7 2015
.UPDATE...
ISSUED AT 652 PM CDT TUE APR 7 2015
TWEAKED POPS FOR CURRENT RADAR TRENDS...THINK THAT THE PRECIP
SHOULD CONTINUE TO MOVE EASTWARD THROUGH THE RED RIVER VALLEY AND
WILL BE MOSTLY IN WESTERN MINNESOTA BY LATE EVENING. REPORTS HAVE
1 TO 2 INCHES MAINLY IN THE NORTHERN COUNTIES...SO WILL KEEP THE
1-3 INCH ACCUMULATIONS NORTH OF HIGHWAY 2 THAT WE HAVE GOING. SREF
PROBABILITIES AND HRRR VIS SHOW SOME FOG IN THE DEVILS LAKE BASIN
TOWARDS MORNING. BUMPED UP MENTION TO AREAS OF FOG AND WILL KEEP
AN EYE ON DENSITY FOR NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 300 PM CDT TUE APR 7 2015
CHALLENGES CENTER AROUND PRECIP AND PRECIP TYPE THROUGH THU...THEN
TEMPS. MODELS ARE IN PRETTY GOOD OVERALL AGREEMENT THROUGH
FRIDAY...LEADING TO SOME INCREASED CONFIDENCE IN THIS FORECAST.
FOR THE REST OF THIS AFTERNOON AND OVERNIGHT...THE BAND OF PRECIP
WILL SLOWLY SHIFT FROM WEST TO EAST. THERE IS STRONG OMEGA/WAA IN
THE MID LEVELS THAT SHOULD TARGET AREAS ALONG AND NORTH OF US
HIGHWAY 2 THROUGH 6Z. EXPECT MOST SNOW IN THE FAR NORTH WITH A MIX
OF RAIN/SNOW POSSIBLE FURTHER SOUTH AND PROBABLY JUST RAIN IN THE
SOUTH. THERE COULD BE AN INCH OR 2 OF SNOW IN THE NORTH THROUGH
THE OVERNIGHT...WITH SOME SLICK SPOTS IF SNOW RATES BECOME HIGH
ENOUGH AND AFTER DARK. TEMPS WON/T FALL TOO MUCH OVERNIGHT GIVEN
THE POTENTIAL OF LOW CLOUDS AND EVEN SOME PATCHY FOG LATE IN THE
WEST. FOR NOW WON/T MENTION FOG...BUT POTENTIAL WILL HAVE TO BE MONITORED.
FOR WED...IT SHOULD BE DRY FOR MOST OF THE DAY...WITH THE THREAT
FOR SOME LIGHT PRECIP MOVING INTO THE WEST AND SOUTH TOWARDS 00Z
THU. TEMPS SHOULD WARM A BIT FROM TODAY...AND HINGE LARGELY ON IF
THERE IS ANY SUNSHINE.
FOR WED NIGHT...THE COLUMN WILL SATURATE AS A LARGE STORM SYSTEM
MOVES INTO THE CENTRAL PLAINS. EXPECT SOME RAIN INITIALLY IN THE
SOUTH WITH PRECIP POSSIBLY MIXING WITH SOME SNOW FURTHER NORTH
OVERNIGHT. NOT EXPECTING HEAVY PRECIP RATES WITH THIS SYSTEM...SO
LITTLE IF ANY SNOW ACCUMS EXPECTED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 300 PM CDT TUE APR 7 2015
FOR THURSDAY...ANY PRECIP SHOULD MOVE OUT OF THE SOUTHEAST FA BY
18Z. TEMPS WILL WARM A BIT FROM WED WITH SOME SUNSHINE EXPECTED.
ON FRIDAY...ANOTHER DRY DAY IS EXPECTED WITH TEMPS SIMILAR TO THU.
THERE WILL BE SOME COOL AIR ALOFT IN THE FAR NORTHEAST...AND CAN/T
RULE OUT A SPRINKLE...BUT FOR NOW WILL KEEP IT DRY.
FOR FRIDAY NIGHT THROUGH TUESDAY...WILL START OFF THE PERIOD WITH
RIDGING AT 500MB AND THUS MILD TEMPS FOR SAT/SUN. THE 12Z GFS SHOWS
A LITTLE PREFRONTAL PCPN ACROSS THE FA AS EARLY AS SATURDAY
AFTERNOON...WHILE THE OTHER MODELS ARE DRY. THINK PCPN CHANCES WILL
INCREASE AS A COLD FRONT MOVES THRU SUNDAY/SUN NIGHT. SHOULD STILL
BE WARM ENOUGH THAT THIS PCPN WILL FALL AS RAIN. MORE UNCERTAINTY
ENTERS THE FORECAST BY MON INTO TUE WITH THE 12Z GFS ESSENTIALLY
DRY. ECMWF SHOWS A LITTLE LIGHT PCPN BUT CONFIDENCE PRETTY LOW AT
THIS POINT. WILL KEEP THE LOW GUIDANCE PCPN CHANCES ON MONDAY BUT
THINK THAT MAY BE OVERDONE. SHOULD BE A LITTLE COOLER MON/TUE BEHIND
THE COLD FRONT BUT TEMPS STILL LOOK TO BE WARMER THAN NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 652 PM CDT TUE APR 7 2015
PRECIP CONTINUES TO MOVE EASTWARD ACROSS THE AREA. IT HAS ENDED IN
KDVL FOR THE NIGHT AND JUST STARTED IN KBJI. THINK THAT THE SITES
ALONG THE RED RIVER WILL SEE -SN/-RA ENDING IN THE NEXT FEW HOURS
WHILE THERE WILL BE SOME LIGHT SNOW A BIT LONGER FURTHER EAST
BEFORE ALL PRECIP ENDS AFTER 06Z. THE SREF HAS HIGH PROBABILITIES
OF VIS LESS THAN 1SM IN THE KDVL AREA TOWARDS MORNING. THINK THAT
LOW CLOUDS WILL BE PROBABLE AND WITH RECENT PRECIP FOG IS
POSSIBLE. JUST INCLUDED 1SM FOR NOW AND WILL TAKE A LOOK IF WE
NEED ANYTHING LOWER AS THE EVENING WEARS ON. AT KGFK AND KFAR KEPT
VIS IN THE MVFR CATEGORY BUT HAVE CIGS BELOW 1000 FT. THINK THAT
MOST SITES SHOULD BE UP TO MVFR BY MID MORNING TOMORROW.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...DK
LONG TERM...GODON/DK
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1251 PM CDT MON APR 6 2015
.UPDATE...
ISSUED AT 1251 PM CDT MON APR 6 2015
GETTING A BIT OF CIRRUS SPREADING OVER THE TOP OF THE MID LEVEL
CLOUDS ACROSS THE SOUTH. THIS WILL LIKELY CONTINUE SPREADING TO
EAST-NE THRU THE AFTERNOON. THEREFORE AREAS ALONG AND NORTH OF
HIGHWAY 2 WILL SEE MORE FILTERED SUN THRU THE AFTERNOON. TEMPS NOT
EXPECTED TO RISE MUCH MORE AS A RESULT. THE WARMEST TEMPS IN THE
LOW 40S ARE CURRENTLY BETWEEN KFAR AND KGFK. WENT AHEAD AND
REMOVED THE LOW PCPN CHANCES ACROSS THE FAR SOUTH FOR THE REST OF
THE AFTERNOON. THINKING THAT PCPN SHOULD HOLD OFF UNTIL THE
EVENING. EVEN THEN THE LATEST HIGH RESOLUTION MODELS SHOW A VERY
SLOW NORTHWARD PROGRESSION TONIGHT AS ANY PCPN BATTLES WITH THE
DRY AIR IN PLACE. BEST CHANCES TONIGHT MAY BE LATE NIGHT INTO TUE
MORNING...BUT WILL LOOK MORE AT THIS FOR THE NEXT UPDATE.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 325 AM CDT MON APR 6 2015
FORECAST CHALLENGES CONTINUE TO BE PCPN CHANCES AND TEMPERATURES.
MODELS CONTINUE TO INITIALIZE WAY TO HIGH WITH PCPN AMOUNTS ACROSS
THE FA. RUC DOING MUCH BETTER SO WILL UTILIZE IN THE NEAR TERM.
OTHERWISE IN LATER PERIODS MODELS FAIRLY CLOSE.
DRY LOW LEVEL NE FLOW CONTINUES TO WIN OUT OVER ANY PCPN. FIRST
BAND OF PCPN ASSOCIATED WITH 700MB FRONTOGENETIC FORCING TRACKING
ACROSS E CENTRAL MN WITHOUT BRINGING ANY MORE THAN A TRACE OF PCPN
ACROSS THE SOUTHERN FA. NEXT BATCH OF RETURNS ACROSS CENTRAL/N
CENTRAL SD NOT VERY IMPRESSIVE AND CIGS UNDER RETURNS IN THE MID
LEVELS. WITH SURFACE HIGH PRESSURE BUILDING SOUTHWARD OUT OF
CANADA FEEL IT WILL BE EVEN TOUGHER TO GET ANY PCPN. RUC MAINLY
DRY TODAY AND GFS K295 SURFACE KEEPING ANY LIFT SOUTH OF THE FA.
FOR THIS CONFINED ANY LOW POPS TO ALONG THE ND/SD BORDER AREA.
LOOKS LIKE A BETTER CHANCE FOR PCPN ACROSS THE REGION TONIGHT INTO
TUESDAY. AS HIGH PRESSURE SHIFTS EAST TONIGHT LOW LEVEL FLOW WILL
BECOME MORE E-SE ALLOWING MORE MOISTURE TO SPREAD INTO THE FA. GFS
295K SURFACE LIFTS A BAND OF LOWERING CONDENSATION PRESSURE
DEFICITS AND ISENTROPIC LIFT NORTHWARD TONIGHT INTO TUESDAY. WITH
MODELS IN PRETTY CLOSE AGREEMENT INCREASED POPS SOME AS BAND LIFTS
NORTHWARD. NATIONAL GUIDANCE SUGGESTING SOME POTENTIAL FOR ZR
ACROSS THE FAR SOUTHERN FA SO WILL NEED TO MONITOR THIS. THERMAL
ADVECTION FAIRLY NEUTRAL AND WITH CLOUDS TEMPERATURES TO REMAIN ON
THE COOL SIDE DURING THE DAY AND NEAR AVERAGE AT NIGHT.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 325 AM CDT MON APR 6 2015
ANY LINGERING PCPN SHOULD LIFT NE OF THE FA TUESDAY NIGHT.
NEXT PCPN CHANCES RETURN MIDWEEK AS WESTERN TROUGH AND ASSOCIATED
SURFACE LOW SHIFTS EAST. NOT MUCH CHANGE IN TEMPERATURES FROM
CURRENT TRENDS.
THURSDAY TO SUNDAY NIGHT...MODELS IN FAIR AGREEMENT WITH THE
PLACEMENT OF THE NORTHERN EXTENT OF RAIN FROM A WELL ORGANIZED UPPER
LEVEL SYSTEM CROSSING THE CENTRAL US. AS A RESULT THERE WILL BE A
CHANCE OF PRECIPITATION ACROSS AREAS ALONG AND SOUTH OF THE I94 HWY
10 CORRIDOR THURSDAY AND FRIDAY. TEMPERATURES FOR THE END OF THE
WEEK AND INTO THE WEEKEND WILL BE IN THE 40S AND 50S THURSDAY AND
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1251 PM CDT MON APR 6 2015
THE DRY AIR CONTINUES TO CAUSE VFR CONDITIONS FOR THE REGION. MODELS
ARE CONSISTENT WITH BRINGING MVFR CIGS/VSBYS WITH SOME SNOW/RAIN
INTO THE REGION FROM WEST TO EAST LATER TONIGHT INTO TUE. HAVE GONE
WITH THIS TREND WITH A BAND OF PRECIP OVERSPREADING MOST OF THE
REGION BY TUE MORNING. EASTERLY WINDS COULD ALSO GUST OVER 20KT ON
TUE WITH PRESSURE GRADIENT TIGHTENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GODON
SHORT TERM...VOELKER
LONG TERM...JK/VOELKER
AVIATION...DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
906 AM CDT MON APR 6 2015
.UPDATE...
ISSUED AT 905 AM CDT MON APR 6 2015
DID SOME CLOUD UPDATES TO MATCH CURRENT CONDITIONS...WHICH ARE
SUNNY ALONG AND NORTH OF HIGHWAY 2 AND MORE CLOUDS TO THE SOUTH.
CURRENT REGIONAL RADAR SHOWS ALL PCPN OUT OF THE FA SO WILL GO DRY
UNTIL POSSIBLY MID TO LATE AFTERNOON. MODELS HAVE STRUGGLED WITH
THESE THIN LITTLE PCPN BANDS IN THIS DRY AIR REGIME. WILL TAKE A
CLOSER LOOK AT TEMPS WITH THE NEXT UPDATE. HIGHS WILL HINGE ON THE
AMOUNT OF SUN TODAY.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 325 AM CDT MON APR 6 2015
FORECAST CHALLENGES CONTINUE TO BE PCPN CHANCES AND TEMPERATURES.
MODELS CONTINUE TO INITIALIZE WAY TO HIGH WITH PCPN AMOUNTS ACROSS
THE FA. RUC DOING MUCH BETTER SO WILL UTILIZE IN THE NEAR TERM.
OTHERWISE IN LATER PERIODS MODELS FAIRLY CLOSE.
DRY LOW LEVEL NE FLOW CONTINUES TO WIN OUT OVER ANY PCPN. FIRST
BAND OF PCPN ASSOCIATED WITH 700MB FRONTOGENETIC FORCING TRACKING
ACROSS E CENTRAL MN WITHOUT BRINGING ANY MORE THAN A TRACE OF PCPN
ACROSS THE SOUTHERN FA. NEXT BATCH OF RETURNS ACROSS CENTRAL/N
CENTRAL SD NOT VERY IMPRESSIVE AND CIGS UNDER RETURNS IN THE MID
LEVELS. WITH SURFACE HIGH PRESSURE BUILDING SOUTHWARD OUT OF
CANADA FEEL IT WILL BE EVEN TOUGHER TO GET ANY PCPN. RUC MAINLY
DRY TODAY AND GFS K295 SURFACE KEEPING ANY LIFT SOUTH OF THE FA.
FOR THIS CONFINED ANY LOW POPS TO ALONG THE ND/SD BORDER AREA.
LOOKS LIKE A BETTER CHANCE FOR PCPN ACROSS THE REGION TONIGHT INTO
TUESDAY. AS HIGH PRESSURE SHIFTS EAST TONIGHT LOW LEVEL FLOW WILL
BECOME MORE E-SE ALLOWING MORE MOISTURE TO SPREAD INTO THE FA. GFS
295K SURFACE LIFTS A BAND OF LOWERING CONDENSATION PRESSURE
DEFICITS AND ISENTROPIC LIFT NORTHWARD TONIGHT INTO TUESDAY. WITH
MODELS IN PRETTY CLOSE AGREEMENT INCREASED POPS SOME AS BAND LIFTS
NORTHWARD. NATIONAL GUIDANCE SUGGESTING SOME POTENTIAL FOR ZR
ACROSS THE FAR SOUTHERN FA SO WILL NEED TO MONITOR THIS. THERMAL
ADVECTION FAIRLY NEUTRAL AND WITH CLOUDS TEMPERATURES TO REMAIN ON
THE COOL SIDE DURING THE DAY AND NEAR AVERAGE AT NIGHT.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 325 AM CDT MON APR 6 2015
ANY LINGERING PCPN SHOULD LIFT NE OF THE FA TUESDAY NIGHT.
NEXT PCPN CHANCES RETURN MIDWEEK AS WESTERN TROUGH AND ASSOCIATED
SURFACE LOW SHIFTS EAST. NOT MUCH CHANGE IN TEMPERATURES FROM
CURRENT TRENDS.
THURSDAY TO SUNDAY NIGHT...MODELS IN FAIR AGREEMENT WITH THE
PLACEMENT OF THE NORTHERN EXTENT OF RAIN FROM A WELL ORGANIZED UPPER
LEVEL SYSTEM CROSSING THE CENTRAL US. AS A RESULT THERE WILL BE A
CHANCE OF PRECIPITATION ACROSS AREAS ALONG AND SOUTH OF THE I94 HWY
10 CORRIDOR THURSDAY AND FRIDAY. TEMPERATURES FOR THE END OF THE
WEEK AND INTO THE WEEKEND WILL BE IN THE 40S AND 50S THURSDAY AND
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 639 AM CDT MON APR 6 2015
VFR CONDITIONS EXPECTED FOR ALL TAFS SITES THROUGH THE PERIOD.
SOME MIXED PCPN SHOULD GET ORGANIZED ACROSS THE FAR SOUTH LATER
TONIGHT LIFTING NORTHWARD MAINLY ON TUESDAY. COULD SEE SOME LOWER
CIGS THEN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GODON
SHORT TERM...VOELKER
LONG TERM...JK/VOELKER
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
643 AM CDT MON APR 6 2015
.UPDATE...
ISSUED AT 639 AM CDT MON APR 6 2015
LOOKING LESS AND LESS THAT THE FAR SOUTHERN FA WILL GET ANY PCPN.
CONTINUED TO TRIM POPS THERE THROUGH THE MORNING. NO OTHER CHANGES.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 325 AM CDT MON APR 6 2015
FORECAST CHALLENGES CONTINUE TO BE PCPN CHANCES AND TEMPERATURES.
MODELS CONTINUE TO INITIALIZE WAY TO HIGH WITH PCPN AMOUNTS ACROSS
THE FA. RUC DOING MUCH BETTER SO WILL UTILIZE IN THE NEAR TERM.
OTHERWISE IN LATER PERIODS MODELS FAIRLY CLOSE.
DRY LOW LEVEL NE FLOW CONTINUES TO WIN OUT OVER ANY PCPN. FIRST
BAND OF PCPN ASSOCIATED WITH 700MB FRONTOGENETIC FORCING TRACKING
ACROSS E CENTRAL MN WITHOUT BRINGING ANY MORE THAN A TRACE OF PCPN
ACROSS THE SOUTHERN FA. NEXT BATCH OF RETURNS ACROSS CENTRAL/N
CENTRAL SD NOT VERY IMPRESSIVE AND CIGS UNDER RETURNS IN THE MID
LEVELS. WITH SURFACE HIGH PRESSURE BUILDING SOUTHWARD OUT OF
CANADA FEEL IT WILL BE EVEN TOUGHER TO GET ANY PCPN. RUC MAINLY
DRY TODAY AND GFS K295 SURFACE KEEPING ANY LIFT SOUTH OF THE FA.
FOR THIS CONFINED ANY LOW POPS TO ALONG THE ND/SD BORDER AREA.
LOOKS LIKE A BETTER CHANCE FOR PCPN ACROSS THE REGION TONIGHT INTO
TUESDAY. AS HIGH PRESSURE SHIFTS EAST TONIGHT LOW LEVEL FLOW WILL
BECOME MORE E-SE ALLOWING MORE MOISTURE TO SPREAD INTO THE FA. GFS
295K SURFACE LIFTS A BAND OF LOWERING CONDENSATION PRESSURE
DEFICITS AND ISENTROPIC LIFT NORTHWARD TONIGHT INTO TUESDAY. WITH
MODELS IN PRETTY CLOSE AGREEMENT INCREASED POPS SOME AS BAND LIFTS
NORTHWARD. NATIONAL GUIDANCE SUGGESTING SOME POTENTIAL FOR ZR
ACROSS THE FAR SOUTHERN FA SO WILL NEED TO MONITOR THIS. THERMAL
ADVECTION FAIRLY NEUTRAL AND WITH CLOUDS TEMPERATURES TO REMAIN ON
THE COOL SIDE DURING THE DAY AND NEAR AVERAGE AT NIGHT.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 325 AM CDT MON APR 6 2015
ANY LINGERING PCPN SHOULD LIFT NE OF THE FA TUESDAY NIGHT.
NEXT PCPN CHANCES RETURN MIDWEEK AS WESTERN TROUGH AND ASSOCIATED
SURFACE LOW SHIFTS EAST. NOT MUCH CHANGE IN TEMPERATURES FROM
CURRENT TRENDS.
THURSDAY TO SUNDAY NIGHT...MODELS IN FAIR AGREEMENT WITH THE
PLACEMENT OF THE NORTHERN EXTENT OF RAIN FROM A WELL ORGANIZED UPPER
LEVEL SYSTEM CROSSING THE CENTRAL US. AS A RESULT THERE WILL BE A
CHANCE OF PRECIPITATION ACROSS AREAS ALONG AND SOUTH OF THE I94 HWY
10 CORRIDOR THURSDAY AND FRIDAY. TEMPERATURES FOR THE END OF THE
WEEK AND INTO THE WEEKEND WILL BE IN THE 40S AND 50S THURSDAY AND
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 639 AM CDT MON APR 6 2015
VFR CONDITIONS EXPECTED FOR ALL TAFS SITES THROUGH THE PERIOD.
SOME MIXED PCPN SHOULD GET ORGANIZED ACROSS THE FAR SOUTH LATER
TONIGHT LIFTING NORTHWARD MAINLY ON TUESDAY. COULD SEE SOME LOWER
CIGS THEN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...VOELKER
LONG TERM...JK/VOELKER
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
332 AM CDT MON APR 6 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 325 AM CDT MON APR 6 2015
FORECAST CHALLENGES CONTINUE TO BE PCPN CHANCES AND TEMPERATURES.
MODELS CONTINUE TO INITIALIZE WAY TO HIGH WITH PCPN AMOUNTS ACROSS
THE FA. RUC DOING MUCH BETTER SO WILL UTILIZE IN THE NEAR TERM.
OTHERWISE IN LATER PERIODS MODELS FAIRLY CLOSE.
DRY LOW LEVEL NE FLOW CONTINUES TO WIN OUT OVER ANY PCPN. FIRST
BAND OF PCPN ASSOCIATED WITH 700MB FRONTOGENETIC FORCING TRACKING
ACROSS E CENTRAL MN WITHOUT BRINGING ANY MORE THAN A TRACE OF PCPN
ACROSS THE SOUTHERN FA. NEXT BATCH OF RETURNS ACROSS CENTRAL/N
CENTRAL SD NOT VERY IMPRESSIVE AND CIGS UNDER RETURNS IN THE MID
LEVELS. WITH SURFACE HIGH PRESSURE BUILDING SOUTHWARD OUT OF
CANADA FEEL IT WILL BE EVEN TOUGHER TO GET ANY PCPN. RUC MAINLY
DRY TODAY AND GFS K295 SURFACE KEEPING ANY LIFT SOUTH OF THE FA.
FOR THIS CONFINED ANY LOW POPS TO ALONG THE ND/SD BORDER AREA.
LOOKS LIKE A BETTER CHANCE FOR PCPN ACROSS THE REGION TONIGHT INTO
TUESDAY. AS HIGH PRESSURE SHIFTS EAST TONIGHT LOW LEVEL FLOW WILL
BECOME MORE E-SE ALLOWING MORE MOISTURE TO SPREAD INTO THE FA. GFS
295K SURFACE LIFTS A BAND OF LOWERING CONDENSATION PRESSURE
DEFICITS AND ISENTROPIC LIFT NORTHWARD TONIGHT INTO TUESDAY. WITH
MODELS IN PRETTY CLOSE AGREEMENT INCREASED POPS SOME AS BAND LIFTS
NORTHWARD. NATIONAL GUIDANCE SUGGESTING SOME POTENTIAL FOR ZR
ACROSS THE FAR SOUTHERN FA SO WILL NEED TO MONITOR THIS. THERMAL
ADVECTION FAIRLY NEUTRAL AND WITH CLOUDS TEMPERATURES TO REMAIN ON
THE COOL SIDE DURING THE DAY AND NEAR AVERAGE AT NIGHT.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 325 AM CDT MON APR 6 2015
ANY LINGERING PCPN SHOULD LIFT NE OF THE FA TUESDAY NIGHT.
NEXT PCPN CHANCES RETURN MIDWEEK AS WESTERN TROUGH AND ASSOCIATED
SURFACE LOW SHIFTS EAST. NOT MUCH CHANGE IN TEMPERATURES FROM
CURRENT TRENDS.
THURSDAY TO SUNDAY NIGHT...MODELS IN FAIR AGREEMENT WITH THE
PLACEMENT OF THE NORTHERN EXTENT OF RAIN FROM A WELL ORGANIZED UPPER
LEVEL SYSTEM CROSSING THE CENTRAL US. AS A RESULT THERE WILL BE A
CHANCE OF PRECIPITATION ACROSS AREAS ALONG AND SOUTH OF THE I94 HWY
10 CORRIDOR THURSDAY AND FRIDAY. TEMPERATURES FOR THE END OF THE
WEEK AND INTO THE WEEKEND WILL BE IN THE 40S AND 50S THURSDAY AND
FRIDAY WARMER INTO THE 50S TO NEAR 60 FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1139 PM CDT SUN APR 5 2015
LIGHT SNOW IN DVL REGION WILL END AROUND 06Z OR SO. CIGS WILL RISE
BACK INTO VFR RANGE AND STAY THAT WAY THROUGH MONDAY EVE. OTHER
TAF SITES SUCH AS GFK/TVF/BJI TO REMAIN VFR AS WELL AND LIKELY
LOSE THE VFR MID CLOUD DECK MONDAY AS DRIER AIR DRIVES BACK SOUTH.
FARGO AREA LOOKING LESS LIKELY TO GET ANY LIGHT SNOW AS DEW PTS
HAVE FALLEN A FEW DEGREES THIS EVE. THUS KEPT THEM VFR CIGS INTO
MONDAY BUT DRY. WINDS ALL AREAS GENERALLY NORTHEAST 8 TO 15 KTS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...VOELKER
LONG TERM...JK/VOELKER
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
739 PM EDT TUE APR 7 2015
.SYNOPSIS...
A WARM AND MOIST SOUTH TO SOUTHWEST WIND FLOW WILL BRING ROUNDS OF
SHOWERS AND THUNDERSTORMS THROUGHOUT THE WEEK. COLD FRONT CROSSES AT
THE END OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
LOTS OF CONVECTION TO OUR WEST...WITH ONLY LINGERING MASS ACROSS THE
NORTHERN MOUNTAINS. TO OUR WEST...HAVE AREA BETWEEN KHTS AND
KLEX...MOVING SOUTHEAST ALONG A WEAK SURFACE BOUNDARY. THIS
CONVECTION WILL MOVE ACROSS THE SOUTHERN CWA LATE THIS AFTERNOON
INTO THIS EVENING. FARTHER WEST...IN SOUTHERN INDIANA HAVE
ANOTHER COMPLEX MOVING EAST. NAM/HRRR AND SOME WRF RUNS SHOW A MCV
WITH THIS MOVING ACROSS SOUTHERN CWA TONIGHT. RAP IS A BIT FARTHER
NORTH. AS A SURFACE LOW MOVES THROUGH MISSOURI TONIGHT...EXPECT
THE SURFACE BOUNDARY TO SLOWLY MOVE NORTH CROSSING SOUTHERN CWA
DURING THE EARLY MORNING. WITH A FAIRLY WET GROUND IN PLACE ACROSS
SOUTHERN CWA AFTER HEAVY RAIN LATE LAST WEEK...AND ANTICIPATING
ANOTHER COUPLE ROUNDS OF AT LEAST MODERATE RAIN TONIGHT...WITH GO
WITH A FLASH FLOOD WATCH ALONG AND SOUTH OF I-64. BEST CASE
SCENARIO IS THE HEAVIEST RAIN STICKS CLOSER TO THE INFLOW AND
REMAINS MAINLY SOUTH OF CWA...WITH JUST A PERIOD OF LIGHT TO
MODERATE RAIN WITH THE REMNANTS OF THE MCV. WORST CASE WOULD BE IF
EACH WAVE CROSSES THROUGH THE SAME AREA OF SOUTHERN CWA.
EXPECT A BREAK IN PRECIP...ALTHOUGH CANNOT RULE OUT AN ISOLATED
SHOWER...THROUGH MUCH OF WEDNESDAY MORNING. HAVE ANOTHER AREA OF
LIKELY POPS MOVING FROM WEST TO EAST ACROSS CWA WEDNESDAY AFTERNOON
AS A SHORTWAVE TROUGH MOVES OVER.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
MODELS ARE CLOSER TO AGREEMENT...ON LIFTING A SURFACE BOUNDARY AND
UPPER IMPULSE NORTH ACROSS THE AREA WEDNESDAY NIGHT...FOLLOWED BY A
COLD FRONT LATE THURSDAY NIGHT AND FRIDAY. WITH MOIST AND UNSTABLE
AIR IN PLACE...THESE TWO FEATURES WILL BE THE FOCUS FOR SHOWERS AND
THUNDERSTORMS...ESPECIALLY THE COLD FRONT. IN BETWEEN...IN THE WARM
SECTOR ON THURSDAY...THERE COULD BE A SHOWER OR THUNDERSTORM
ESPECIALLY IN THE AFTERNOON WITH HEATING. TIMING OF COLD FRONT HAS
IT REACHING THE OHIO RIVER AROUND DAWN FRIDAY...THEN PROGRESSING
ACROSS THE REMAINDER OF AREA DURING FRIDAY. WITH GOOD UPPER SUPPORT
AND PLENTY OF WARM AND MOIST UNSTABLE AIR...A BAND OF ORGANIZED
SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ALONG AND AHEAD OF THE
COLD FRONT. WILL HAVE TO WATCH FOR WATER PROBLEMS AND STRONG STORMS
IN THIS TIME FRAME. UPON COLD FRONT PASSAGE FRIDAY...EXPECT
IMPROVEMENT FROM THE WEST. TEMPERATURE RANGES THIS PERIOD WILL BE
LOWERED SOMEWHAT BY THE CLOUDS AND SHOWERS...BUT THURSDAY MAY BE
WARMER THAN FORECAST IF SUNSHINE MAKES A DETERMINED APPEARANCE IN
THE WARM SECTOR. IN ANY CASE...NO EXTREMES IN TEMPERATURE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MODELS ARE QUICKER WITH THE COLD FRONTAL PASSAGE ON FRIDAY LEAVING
FRIDAY NIGHT MOSTLY DRY. THE OUTLIER IS THE ECMWF WHICH LAGS ABOUT 6
HOURS IN ITS QPF FIELD. WENT WITH THE CONSENSUS OF MODELS WITH A
FASTER SOLUTIONS.
HIGH PRESSURE BRINGS WIDESPREAD DRY WEATHER FRIDAY NIGHT THROUGH THE
WEEKEND. ANOTHER UPPER WAVE APPROACHES MONDAY BRINGING BACK CHANCES
FOR PCPN ACROSS THE AREA.
TEMPERATURES EXPECTED TO BE WARM REACHING THE UPPER 70S THROUGH THE
PERIOD...EXCEPT FOR A SLIGHT COOL DOWN BEHIND THE COLD FRONT
SATURDAY...GENERALLY IN THE MID TO UPPER 60S. WENT CLOSE TO WPC
GUIDANCE WITH FEW TWEAKS THROUGH THE PERIOD.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AN AREA OF THUNDERSTORMS WILL DRIFT EASTWARD ACROSS CWA DURING
THIS TAF PERIOD. GENERALLY WENT MVFR DURING STORMS DUE TO HIGH
BASES AND UNCERTAINTY ON TIMING. WOULD NOT BE SURPRISED TO GET
PERIODS OF IFR IN HEAVIER RAIN. BEST CHANCE OF SHOWERS/STORMS THIS
EVENING AND TONIGHT WILL BE ACROSS THE SOUTH. ALSO THERE MAY BE
SOME SOME MVFR FOG BEHIND TONIGHTS BATCH OF SHOWERS...MAINLY
ACROSS THE SOUTH.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z THURSDAY...
FORECAST CONFIDENCE: LOW.
ALTERNATE SCENARIOS: TIMING OF SHOWERS AND THUNDERSTORMS COULD VARY.
FOG COULD FORM IN AREAS RECEIVING RAINFALL TUESDAY NIGHT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE WED 04/08/15
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
CRW CONSISTENCY H H M H H H H H M M M M
HTS CONSISTENCY H M M M M M M M H H H H
BKW CONSISTENCY H H H M H H M H H H H H
EKN CONSISTENCY H H H H H H M M H L L L
PKB CONSISTENCY H H H M H H H H H H L L
CKB CONSISTENCY H H H H M H M M L L L L
AFTER 00Z THURSDAY...
BRIEF IFR POSSIBLE IN SHOWERS AND/OR THUNDERSTORMS THROUGH FRIDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR WVZ005-006-
013>015-024>026-033>036.
OH...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR OHZ087.
KY...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR KYZ101>103-105.
VA...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR VAZ003-004.
&&
$$
SYNOPSIS...ARJ/JMV/MZ
NEAR TERM...MZ
SHORT TERM...JMV
LONG TERM...ARJ
AVIATION...JW
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
428 PM EDT MON APR 6 2015
.SYNOPSIS...
AN EAST-TO-WEST ORIENTED FRONTAL BOUNDARY WILL SET UP ACROSS THE
SOUTHERN GREAT LAKES AND NORTHERN OHIO VALLEY THIS WEEK. THIS WILL
LEAD TO OCCASIONAL CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH
FRIDAY MORNING...BEFORE A COLD FRONT MOVES THROUGH THE REGION.
DRIER CONDITIONS ARE EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
ISENTROPIC ASCENT IS UNDERWAY ACROSS THE ILN FORECAST AREA...WITH
STRONG THETA-E ADVECTION AT AND ABOVE 925MB...AND WEAKER ADVECTION
NEAR THE SURFACE. THERE IS CURRENTLY LITTLE IN THE WAY OF
ADDITIONAL FORCING...SO SHOWERS HAVE BEEN FAIRLY SCATTERED.
HOWEVER...AS WEAK ELEVATED INSTABILITY HAS BEGUN TO NOSE INTO THE
SOUTHWESTERN PORTIONS OF THE CWA...COVERAGE AND INTENSITY HAS
SHOWN A SLIGHT INCREASE OVER THE PAST HOUR OR TWO. THIS INCREASE
IS EXPECTED TO CONTINUE OVER AT LEAST THE NEXT FEW HOURS...THOUGH
THE ACTIVITY WILL REMAIN SOMEWHAT ELEVATED AND ANY CONVECTION
SHOULD BE WEAK.
OVERNIGHT...THERE MAY NOT BE A TRUE DIURNAL MINIMUM...AS
CONVECTION IS EXPECTED TO INCREASE IN COVERAGE TOWARD TUESDAY
MORNING. MIN TEMPERATURES WILL NOT FALL SIGNIFICANTLY FROM VALUES
THIS AFTERNOON...AND THE TEMPERATURE TRACE MAY EVEN BE SLIGHTLY
NON-DIURNAL (WITH NEARLY STEADY TEMPERATURES THROUGH THE SECOND
HALF OF THE OVERNIGHT HOURS).
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
ON TUESDAY MORNING...SURFACE HIGH PRESSURE WILL BE CENTERED OFF
THE SOUTHEAST COAST. LOW PRESSURE DEVELOPING OVER THE HIGH PLAINS
WILL BE ATTACHED TO A NEARLY-STATIONARY FRONTAL BOUNDARY...WHICH
WILL EXTEND WEST-TO-EAST ACROSS THE SOUTHERN GREAT LAKES AND
NORTHERN OHIO VALLEY. WITH GENERALLY ZONAL FLOW AT 500MB...THIS
WILL SET UP A PATTERN OF CONTINUED WARM ADVECTION...A
STRENGTHENING PRESSURE GRADIENT...AND MOISTURE TRANSPORT INTO THE
OHIO VALLEY. ON THE NOSE OF A STRONG LOW-LEVEL JET...CONVECTION IS
EXPECTED TO INCREASE IN COVERAGE MARKEDLY ON TUESDAY
MORNING...ESPECIALLY ACROSS THE SOUTHERN HALF OF THE FORECAST
AREA. BECAUSE THIS MORNING ACTIVITY IS EXPECTED TO REMAIN BASED
PRIMARILY ON ELEVATED INSTABILITY...STRONG STORMS WILL BE FAIRLY
UNLIKELY...THOUGH MODERATE SHEAR COULD LEAD TO A LITTLE BIT OF
ORGANIZATION OR SOME SMALL HAIL (EVEN IF NEAR-SURFACE ISOTHERMAL
OR STABLE CONDITIONS DO NOT SUPPORT MUCH WIND MIXING DOWN).
12Z FORECAST MODELS (AND THE 18Z NAM) ARE SUPPORTING A WETTER
SCENARIO FOR TUESDAY AFTERNOON...WITH ADDITIONAL PROLONGED
CONVECTION OCCURRING ACROSS THE SOUTHERN PORTIONS OF THE FORECAST
AREA. IF THERE IS ANY CONCERN HERE...IT WILL BE THAT INSTABILITY
WILL LIKELY BECOME SURFACE BASED (AS TEMPERATURES CLIMB INTO THE
LOWER 70S AND DEWPOINTS REACH THE UPPER 50S TO NEAR 60). FROM HERE
ON OUT...THE MESOSCALE FEATURES (AND THE POSITION OF THE
OSCILLATING FRONT) WILL DOMINATE THE CONVECTIVE POTENTIAL...MAKING
DETAILED STORM TIMING AND PLACEMENT FORECASTS VERY DIFFICULT. IN
ADDITION...AFTER LOOKING AT VARIOUS BUFKIT SOUNDING SOLUTIONS
DURING AND AFTER THE FIRST ROUND OR TWO OF STORMS...IT IS CLEAR
THAT THERE ARE AN ARRAY OF POSSIBILITIES FOR HOW THE ATMOSPHERE
WILL TURN ITSELF OVER (AND HOW MUCH INSTABILITY CAN DEVELOP OR
REDEVELOP). THUS...WITH MODERATE SHEAR EXPECTED TO
CONTINUE...THE POSSIBILITY FOR STRONG STORMS ON TUESDAY AFTERNOON
CANNOT BE TOTALLY DISCOUNTED. A LULL IN ACTIVITY ON TUESDAY NIGHT
DOES APPEAR LIKELY...BEFORE A SIMILARLY UNCERTAIN PATTERN SETS UP
AGAIN FOR WEDNESDAY.
THE TEMPERATURE FORECAST THROUGH THE SHORT TERM WILL BE FAIRLY
WARM...WITH THE ILN CWA GENERALLY EXPECTED (BY MOST MODELS) TO
REMAIN ON THE WARM SIDE OF THE FRONTAL BOUNDARY. ON
WEDNESDAY...THIS BOUNDARY WILL BE VERY CLOSE TO THE NORTHERN
CWA...SO THERE WILL LIKELY BE A SHARP TEMPERATURE GRADIENT NORTH
OF DAYTON AND COLUMBUS. HOWEVER...THIS FORECAST HAS TRENDED TOWARD
THE WARMER SIDE OF THE SOLUTIONS.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
RISING MID LEVEL HEIGHTS AHEAD OF A MID LEVEL TROUGH WILL NUDGE A
FRONTAL BOUNDARY NORTH AS A WARM FRONT ON THURSDAY. CONVECTION
SHOULD BE ONGOING THURSDAY MORNING...BUT THEN A DECREASE IN COVERAGE
SHOULD OCCUR AS THE WARM FRONT LIFTS NORTH. IT SHOULD BE THE WARMEST
DAY OF THE WEEK AS REGION BECOMES MORE ENTRENCHED IN THE WARM
SECTOR. HIGHS WILL RANGE FROM THE LOWER 70S NORTH TO THE UPPER 70S
SOUTH.
FOR THE PERIOD THURSDAY NIGHT INTO FRIDAY...MODELS ARE NOW
SUGGESTING THAT MID LEVEL TROUGH WILL PUSH A COLD FRONT THROUGH OUR
AREA SOMETIME DURING FRIDAY MORNING/EARLY AFTERNOON. THIS WILL BE AN
UNFAVORABLE TIME FOR SEVERE POTENTIAL SO WILL CONTINUE TO MONITOR
LATER MODEL RUNS TO SEE IF TIMING CHANGES AT ALL. OTHERWISE...WILL
CONTINUE WITH LIKELY POPS ALONG AND AHEAD OF FRONTAL PASSAGE.
FOR FRIDAY NIGHT INTO SATURDAY...COLD FRONT PUSHES EAST AS SURFACE
HIGH PRESSURE BUILDS INTO THE AREA. COOLER WEATHER WILL RETURN WITH
HIGHS RANGING FROM THE MID 50S NORTH THE LOWER 60S SOUTH ON SATURDAY.
FOR SUNDAY INTO MONDAY...HIGH PRESSURE IS FORECAST TO MOVE EAST. A
WARM FRONT WILL LIFT TOWARD THE OHIO VALLEY BY SUNDAY NIGHT.
THEREAFTER...A COLD FRONT WILL APPROACH THE REGION FROM THE WEST
LATE MONDAY. WITH RETURN...MOIST FLOW...THE THREAT FOR
SHOWERS/STORMS WILL ONCE AGAIN INCREASE. TEMPERATURES WILL WARM TO
ABOVE NORMAL READINGS ONCE AGAIN.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
ALL SITES CURRENTLY VFR WITH ONLY ISOLATED LIGHT RAIN. FIRST
UPPER LEVEL DISTURBANCE THAT WAS SCHEDULED TO COME THROUGH THIS
EVENING HAS NOW SHIFTED FURTHER TO THE SOUTH TAKING THE BEST
CHANCES OF RAIN SOUTH WITH IT. HIGH RES NCEP WRF/ RAP STILL
SHOWING SOME DEVELOPMENT THIS AFTERNOON INTO EVENING THOUGH SO
WILL LEAVE MENTION IN FOR TAF SITES IN THE EAST. ANOTHER UPPER
LEVEL DISTURBANCE IS FORECASTED TO APPROACH FROM THE WEST TOMORROW
MORNING. HIGH RES MODELS HAVE SHOWED THIS RAIN SHIFTED FURTHER TO
THE SOUTH WHILE THE NAM BRINGS SOME PRECIP THROUGH OUR AREA. A
THIRD UPPER LEVEL DISTURBANCE WILL MOVE OVERHEAD TUESDAY AFTERNOON
WHICH WILL PROVIDE ANOTHER CHANCE OF RAIN. GLOBAL MODELS ARE AGAIN
SHOWING WIDESPREAD LIFR TO IFR CONDITIONS TUESDAY MORNING. GLOBAL
MODELS HAVE PERFORMED POORLY WITH LOW LEVEL RH AS OF LATE SO HAVE
DELAYED ONSET OF CIGS AND KEPT EVERYONE MVFR.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES POSSIBLE MONDAY NIGHT
THROUGH FRIDAY ALONG WITH A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...HICKMAN
AVIATION...HAINES
THE NEAR TERM AND SHORT TERM FORECAST DISCUSSIONS WILL BE UPDATED
SHORTLY.
PREVIOUS DISCUSSION >
NOT TO MANY CHANGES TO FORECAST THIS MORNING. LIGHT RAIN HAS MOVED
FROM WEST TO EAST THIS MORNING WITH MORE LIGHT RETURNS PUSHING IN
FROM THE WEST. A SHORTWAVE IS EXPECTED TO PUSH IN FROM THE
SOUTHWEST LATE THIS AFTERNOON INTO EVENING WHICH WILL HELP EXPAND
THE COVERAGE. HIGH RES MODELS AND NAM SHOWING COVERAGE EXPANDING
MORE IN OUR SOUTHEAST ZONES. HAVE RAISED POPS IN THE SOUTHEAST TO
ACCOUNT FOR THIS. COULD ALSO GET SOME THUNDER AS FORECAST
SOUNDINGS SHOWING K INDEX VALUES RISING TO NEAR 35. CAPE IS SKINNY
THOUGH AND DRY AIR ENTRAINMENT MIGHT LIMIT SOME OF THE THUNDER.
EXPECT HIGHS TO BE IN THE MID 60S TODAY AS SKIES REMAIN MOSTLY
CLOUDY TO OVERCAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
EAST-WEST FRONT LOCATED NORTH OF THE REGION WILL START TO SAG INTO
THE FORECAST AREA TONIGHT. PRETTY STRONG SIGNAL THAT SHOWERS AND
STORMS WILL DEVELOP ALONG THE BOUNDARY AND THEN MOVE EAST
SOUTHEAST ACROSS THE REGION LATE TONIGHT...EXITING TUESDAY
MORNING. IT IS NOT CLEAR WHETHER THIS WILL BE THE ONLY ACTIVITY ON
TUESDAY OR WHETHER ADDITIONAL CONVECTION MAY DEVELOP. SEEMED
PRUDENT TO KEEP CHANCE POPS IN THE AFTERNOON AS IT MAY NOT TAKE
MUCH TO GENERATE MORE SHOWERS AND STORMS WITH A MOIST...SLIGHTLY
UNSTABLE AND WEAKLY CAPPED ATMOSPHERE IN PLACE AND A FRONT IN THE
VICINITY.
00Z MODELS ARE INDICATING DIFFERENCES IN HOW FAR SOUTH THE FRONT
WILL TRACK THROUGH WEDNESDAY. THIS COULD HAVE AN IMPACT ON
CONVECTIVE COVERAGE AS WELL AS TEMPERATURES. USED A BROAD BRUSH
ENSEMBLE APPROACH WITH CHANCE POPS BOTH TUESDAY NIGHT AND
WEDNESDAY.
TEMPERATURES WILL BE WELL ABOVE NORMAL THROUGH THE PERIOD EXPECT
IN WEST CENTRAL OHIO WHICH SHOULD END UP ON THE NORTH SIDE OF THE
FRONT WITH MUCH COOLER HIGHS BOTH TUESDAY AND WEDNESDAY COMPARED
TO THE REST OF THE FORECAST AREA. FORECAST GENERALLY STAYED WITHIN
A FEW DEGREES OF GFS MOS TEMPERATURES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
RISING MID LEVEL HEIGHTS AHEAD OF A MID LEVEL TROUGH WILL NUDGE A
FRONTAL BOUNDARY NORTH AS A WARM FRONT ON THURSDAY. CONVECTION
SHOULD BE ONGOING THURSDAY MORNING...BUT THEN A DECREASE IN COVERAGE
SHOULD OCCUR AS THE WARM FRONT LIFTS NORTH. IT SHOULD BE THE WARMEST
DAY OF THE WEEK AS REGION BECOMES MORE ENTRENCHED IN THE WARM
SECTOR. HIGHS WILL RANGE FROM THE LOWER 70S NORTH TO THE UPPER 70S
SOUTH.
FOR THE PERIOD THURSDAY NIGHT INTO FRIDAY...MODELS ARE NOW
SUGGESTING THAT MID LEVEL TROUGH WILL PUSH A COLD FRONT THROUGH OUR
AREA SOMETIME DURING FRIDAY MORNING/EARLY AFTERNOON. THIS WILL BE AN
UNFAVORABLE TIME FOR SEVERE POTENTIAL SO WILL CONTINUE TO MONITOR
LATER MODEL RUNS TO SEE IF TIMING CHANGES AT ALL. OTHERWISE...WILL
CONTINUE WITH LIKELY POPS ALONG AND AHEAD OF FRONTAL PASSAGE.
FOR FRIDAY NIGHT INTO SATURDAY...COLD FRONT PUSHES EAST AS SURFACE
HIGH PRESSURE BUILDS INTO THE AREA. COOLER WEATHER WILL RETURN WITH
HIGHS RANGING FROM THE MID 50S NORTH THE LOWER 60S SOUTH ON SATURDAY.
FOR SUNDAY INTO MONDAY...HIGH PRESSURE IS FORECAST TO MOVE EAST. A
WARM FRONT WILL LIFT TOWARD THE OHIO VALLEY BY SUNDAY NIGHT.
THEREAFTER...A COLD FRONT WILL APPROACH THE REGION FROM THE WEST
LATE MONDAY. WITH RETURN...MOIST FLOW...THE THREAT FOR
SHOWERS/STORMS WILL ONCE AGAIN INCREASE. TEMPERATURES WILL WARM TO
ABOVE NORMAL READINGS ONCE AGAIN.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
ALL SITES CURRENTLY VFR WITH ONLY ISOLATED LIGHT RAIN. FIRST
UPPER LEVEL DISTURBANCE THAT WAS SCHEDULED TO COME THROUGH THIS
EVENING HAS NOW SHIFTED FURTHER TO THE SOUTH TAKING THE BEST
CHANCES OF RAIN SOUTH WITH IT. HIGH RES NCEP WRF/ RAP STILL
SHOWING SOME DEVELOPMENT THIS AFTERNOON INTO EVENING THOUGH SO
WILL LEAVE MENTION IN FOR TAF SITES IN THE EAST. ANOTHER UPPER
LEVEL DISTURBANCE IS FORECASTED TO APPROACH FROM THE WEST TOMORROW
MORNING. HIGH RES MODELS HAVE SHOWED THIS RAIN SHIFTED FURTHER TO
THE SOUTH WHILE THE NAM BRINGS SOME PRECIP THROUGH OUR AREA. A
THIRD UPPER LEVEL DISTURBANCE WILL MOVE OVERHEAD TUESDAY AFTERNOON
WHICH WILL PROVIDE ANOTHER CHANCE OF RAIN. GLOBAL MODELS ARE AGAIN
SHOWING WIDESPREAD LIFR TO IFR CONDITIONS TUESDAY MORNING. GLOBAL
MODELS HAVE PERFORMED POORLY WITH LOW LEVEL RH AS OF LATE SO HAVE
DELAYED ONSET OF CIGS AND KEPT EVERYONE MVFR.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES POSSIBLE MONDAY NIGHT
THROUGH FRIDAY ALONG WITH A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HAINES
NEAR TERM...HAINES
SHORT TERM...
LONG TERM...HICKMAN
AVIATION...HAINES
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
146 PM EDT MON APR 6 2015
.SYNOPSIS...
AN EAST-WEST ORIENTED FRONT EXTENDING ACROSS THE LOWER GREAT
LAKES WILL SLOWLY SAG SOUTH INTO THE AREA DURING THE FIRST HALF OF
THE WEEK. THE FRONT WILL STALL NORTH OF THE OHIO RIVER LATE
WEDNESDAY AND THEN LIFT BACK NORTH ON THURSDAY. A COLD FRONT WILL
SWEEP THROUGH THE AREA ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NOT TO MANY CHANGES TO FORECAST THIS MORNING. LIGHT RAIN HAS MOVED
FROM WEST TO EAST THIS MORNING WITH MORE LIGHT RETURNS PUSHING IN
FROM THE WEST. A SHORTWAVE IS EXPECTED TO PUSH IN FROM THE
SOUTHWEST LATE THIS AFTERNOON INTO EVENING WHICH WILL HELP EXPAND
THE COVERAGE. HIGH RES MODELS AND NAM SHOWING COVERAGE EXPANDING
MORE IN OUR SOUTHEAST ZONES. HAVE RAISED POPS IN THE SOUTHEAST TO
ACCOUNT FOR THIS. COULD ALSO GET SOME THUNDER AS FORECAST
SOUNDINGS SHOWING K INDEX VALUES RISING TO NEAR 35. CAPE IS SKINNY
THOUGH AND DRY AIR ENTRAINMENT MIGHT LIMIT SOME OF THE THUNDER.
EXPECT HIGHS TO BE IN THE MID 60S TODAY AS SKIES REMAIN MOSTLY
CLOUDY TO OVERCAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
EAST-WEST FRONT LOCATED NORTH OF THE REGION WILL START TO SAG INTO
THE FORECAST AREA TONIGHT. PRETTY STRONG SIGNAL THAT SHOWERS AND
STORMS WILL DEVELOP ALONG THE BOUNDARY AND THEN MOVE EAST
SOUTHEAST ACROSS THE REGION LATE TONIGHT...EXITING TUESDAY
MORNING. IT IS NOT CLEAR WHETHER THIS WILL BE THE ONLY ACTIVITY ON
TUESDAY OR WHETHER ADDITIONAL CONVECTION MAY DEVELOP. SEEMED
PRUDENT TO KEEP CHANCE POPS IN THE AFTERNOON AS IT MAY NOT TAKE
MUCH TO GENERATE MORE SHOWERS AND STORMS WITH A MOIST...SLIGHTLY
UNSTABLE AND WEAKLY CAPPED ATMOSPHERE IN PLACE AND A FRONT IN THE
VICINITY.
00Z MODELS ARE INDICATING DIFFERENCES IN HOW FAR SOUTH THE FRONT
WILL TRACK THROUGH WEDNESDAY. THIS COULD HAVE AN IMPACT ON
CONVECTIVE COVERAGE AS WELL AS TEMPERATURES. USED A BROAD BRUSH
ENSEMBLE APPROACH WITH CHANCE POPS BOTH TUESDAY NIGHT AND
WEDNESDAY.
TEMPERATURES WILL BE WELL ABOVE NORMAL THROUGH THE PERIOD EXPECT
IN WEST CENTRAL OHIO WHICH SHOULD END UP ON THE NORTH SIDE OF THE
FRONT WITH MUCH COOLER HIGHS BOTH TUESDAY AND WEDNESDAY COMPARED
TO THE REST OF THE FORECAST AREA. FORECAST GENERALLY STAYED WITHIN
A FEW DEGREES OF GFS MOS TEMPERATURES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
FRONT WILL START TO LIFT BACK NORTH WEDNESDAY NIGHT AND MOVE NORTH
OF THE FORECAST AREA ON THURSDAY. APPEARS THAT CONVECTIVE COVERAGE
WILL INCREASE ALONG THIS BOUNDARY AS IT MOVES NORTHWARD. SCATTERED
ACTIVITY WILL STILL BE POSSIBLE IN THE WARM SECTOR. CHANCE OF
SHOWERS AND STORMS WILL INCREASE AGAIN LATE THURSDAY NIGHT INTO
FRIDAY AS A COLD FRONT APPROACHES AND PUSHES THROUGH THE REGION.
HIGH PRESSURE BUILDING IN FOR THE WEEKEND WILL BRING DRY
CONDITIONS AND TEMPERATURES CLOSE TO NORMAL.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
ALL SITES CURRENTLY VFR WITH ONLY ISOLATED LIGHT RAIN. FIRST
UPPER LEVEL DISTURBANCE THAT WAS SCHEDULED TO COME THROUGH THIS
EVENING HAS NOW SHIFTED FURTHER TO THE SOUTH TAKING THE BEST
CHANCES OF RAIN SOUTH WITH IT. HIGH RES NCEP WRF/ RAP STILL
SHOWING SOME DEVELOPMENT THIS AFTERNOON INTO EVENING THOUGH SO
WILL LEAVE MENTION IN FOR TAF SITES IN THE EAST. ANOTHER UPPER
LEVEL DISTURBANCE IS FORECASTED TO APPROACH FROM THE WEST TOMORROW
MORNING. HIGH RES MODELS HAVE SHOWED THIS RAIN SHIFTED FURTHER TO
THE SOUTH WHILE THE NAM BRINGS SOME PRECIP THROUGH OUR AREA. A
THIRD UPPER LEVEL DISTURBANCE WILL MOVE OVERHEAD TUESDAY AFTERNOON
WHICH WILL PROVIDE ANOTHER CHANCE OF RAIN. GLOBAL MODELS ARE AGAIN
SHOWING WIDESPREAD LIFR TO IFR CONDITIONS TUESDAY MORNING. GLOBAL
MODELS HAVE PERFORMED POORLY WITH LOW LEVEL RH AS OF LATE SO HAVE
DELAYED ONSET OF CIGS AND KEPT EVERYONE MVFR.
OUTLOOK...MVFR/IFR CEILINGS AND VISIBILITIES POSSIBLE MONDAY NIGHT THROUGH
FRIDAY ALONG WITH A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HAINES
NEAR TERM...HAINES
SHORT TERM...
LONG TERM...
AVIATION...HAINES
AREA FORECAST DISCUSSION
NWS TULSA OK
935 PM CDT TUE APR 7 2015
...UPDATE...
.DISCUSSION...
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 2 AM FOR THE
NORTHERN TIER OF COUNTIES IN NORTHEAST OKLAHOMA. RAISED POPS IN
THAT AREA EARLIER THIS EVENING BUT SO FAR HAVE HAD NO CONVECTIVE
DEVELOPMENT SOUTH OF THE KANSAS BORDER. STORMS WILL REMAIN
POSSIBLE OVERNIGHT IN THIS AREA. NO OTHER SIGNIFICANT CHANGES TO
THE AFTERNOON FORECAST HAVE BEEN MADE THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 608 PM CDT TUE APR 7 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE 0Z TAFS... VFR CONDITIONS WILL PREVAIL INTO THIS EVENING
AT ALL TAF SITES WITH FAIRLY STRONG SOUTHERLY WINDS CONTINUING. MVFR
CEILINGS ARE EXPECTED TO DEVELOP AREAWIDE BEFORE MIDNIGHT.
THUNDERSTORMS MAY AFFECT NORTHEAST OKLAHOMA SITES THIS EVENING BUT
CHANCES ARE LOW. MORE WIDESPREAD... POSSIBLE STRONG THUNDERSTORMS
WILL AFFECT ALL SITES BEGINNING WEDNESDAY AFTERNOON.
PREV DISCUSSION... /ISSUED 322 PM CDT TUE APR 7 2015/
DISCUSSION...
A WEAK FRONTAL BOUNDARY EXTENDS FROM WEST OF KANSAS CITY INTO NW
OKLAHOMA THIS AFTERNOON WITH A VERY UNSTABLE BUT STRONGLY CAPPED
AIRMASS RESIDING OVER EASTERN OK AND NORTHWEST AR. TEMPS ALONG AND
SE OF THE FRONT HAVE WARMED INTO THE MID 80S TO NEAR 90...AND ALSO
A SUBTLE OUTFLOW BOUNDARY FROM EARLIER STORMS PUSHING THROUGH SW
MISSOURI AT THIS TIME. NO SIGNIFICANT UPPER AIR FORCING AT THIS
POINT...BUT ISOLATED STORMS STILL MAY DEVELOP NEAR THE SFC FRONT
AND OUTFLOW BOUNDARY LATER THIS AFTERNOON OR EARLY THIS EVENING
AS HRRR AND TO A LESSER EXTENT OUR LOCALLY RUN 5KM WRF CONTINUE TO
INDICATE. GIVEN THE AMOUNT OF AVAILABLE CAPE AND AT LEAST MODERATE
SHEAR ANY STORMS COULD BECOME SEVERE SHOULD UPDRAFTS BE
SUSTAINED... LARGE HAIL AND WINDS THE MAIN THREATS. CAP WILL
REMAIN WITH US FOR THE MOST PART THROUGH TONIGHT WITH ONLY A
LIMITED CHANCE OF STORMS NEAR KANSAS AND MISSOURI BORDERS.
UNSTABLE AND CAPPED ENVIRONMENT REMAINS WITH US WEDNESDAY...
HOWEVER WITH UPPER LOW CURRENTLY OFF THE CALIFORNIA COAST MOVING
INTO THE CENTRAL ROCKIES DURING THE DAY...MID LEVEL HEIGHT FALLS
AND A POTENTIAL LEAD SHORT WAVE/ JET STREAK SHOULD HELP ERODE THE
CAP ENOUGH FOR SOME STORMS TO DEVELOP ALONG THE DRY LINE FROM
CENTRAL KS INTO NORTHERN OK. MOST LIKELY TIME WOULD BE 21-00Z
HOWEVER EARLIER RUNS OF THE NAM HAVE SHOWN SOME EARLIER
DEVELOPMENT THAN THAT. WIND PROFILES SUGGEST THAT ONCE A STORM
DEVELOPS IT WILL QUICKLY BECOME SUPERCELLULAR AND POSE A THREAT
FOR VERY LARGE GAIL AND DAMAGING WINDS...AND SOME DEGREE OF
TORNADO POTENTIAL. OVERALL STORM COVERAGE IS EXPECTED TO REMAIN
FAIRLY LIMITED THROUGH WED NIGHT DUE TO PERSISTENT CAP ISSUES.
MAIN UPPER SYSTEM CONTINUES TO PROGRESS EAST THURSDAY WITH A COLD
FRONT OVERTAKING THE DRY LINE AND LIKELY PUSHING THROUGH PARTS OF
NE OKLAHOMA BY EARLY AFTERNOON. CONTINUED MOIST AND VERY UNSTABLE
AHEAD OF THE FRONT WITH MORE WIDESPREAD THUNDERSTORMS LIKELY THU
AFTERNOON AND EVENING MAINLY OVER SOUTHEAST OK AND NORTHWEST AR.
SHEAR PROFILES SUGGEST A MORE LINEAR STORM MODE AT THIS TIME.
STORMS WILL END THU EVENING WITH A COOLER AND STABLE AIRMASS
SETTLING OVER THE AREA FRIDAY.
ANOTHER UPPER LEVEL SYSTEM WILL MOVE IN FROM THE WEST BY THIS
WEEKEND AND WITH THE PRESENCE OF A SFC BOUNDARY IN THE AREA...
THUNDERSTORM CHANCES WILL RETURN BY SATURDAY AND CONTINUE INTO
EARLY NEXT WEEK. GENERAL CONSENSUS IS THIS UPPER LOW WILL
ULTIMATELY TACK A MUCH MORE SOUTHERLY TRACK...ANY SEVERE WEATHER
THREATS DURING THIS TIME REMAIN EXTREMELY UNCERTAIN.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...06
LONG TERM....99
AREA FORECAST DISCUSSION
NWS TULSA OK
608 PM CDT TUE APR 7 2015
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE 0Z TAFS... VFR CONDITIONS WILL PREVAIL INTO THIS EVENING
AT ALL TAF SITES WITH FAIRLY STRONG SOUTHERLY WINDS CONTINUING. MVFR
CEILINGS ARE EXPECTED TO DEVELOP AREAWIDE BEFORE MIDNIGHT.
THUNDERSTORMS MAY AFFECT NORTHEAST OKLAHOMA SITES THIS EVENING BUT
CHANCES ARE LOW. MORE WIDESPREAD... POSSIBLE STRONG THUNDERSTORMS
WILL AFFECT ALL SITES BEGINNING WEDNESDAY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 322 PM CDT TUE APR 7 2015/
DISCUSSION...
A WEAK FRONTAL BOUNDARY EXTENDS FROM WEST OF KANSAS CITY INTO NW
OKLAHOMA THIS AFTERNOON WITH A VERY UNSTABLE BUT STRONGLY CAPPED
AIRMASS RESIDING OVER EASTERN OK AND NORTHWEST AR. TEMPS ALONG AND
SE OF THE FRONT HAVE WARMED INTO THE MID 80S TO NEAR 90...AND ALSO
A SUBTLE OUTFLOW BOUNDARY FROM EARLIER STORMS PUSHING THROUGH SW
MISSOURI AT THIS TIME. NO SIGNIFICANT UPPER AIR FORCING AT THIS
POINT...BUT ISOLATED STORMS STILL MAY DEVELOP NEAR THE SFC FRONT
AND OUTFLOW BOUNDARY LATER THIS AFTERNOON OR EARLY THIS EVENING
AS HRRR AND TO A LESSER EXTENT OUR LOCALLY RUN 5KM WRF CONTINUE TO
INDICATE. GIVEN THE AMOUNT OF AVAILABLE CAPE AND AT LEAST MODERATE
SHEAR ANY STORMS COULD BECOME SEVERE SHOULD UPDRAFTS BE
SUSTAINED... LARGE HAIL AND WINDS THE MAIN THREATS. CAP WILL
REMAIN WITH US FOR THE MOST PART THROUGH TONIGHT WITH ONLY A
LIMITED CHANCE OF STORMS NEAR KANSAS AND MISSOURI BORDERS.
UNSTABLE AND CAPPED ENVIRONMENT REMAINS WITH US WEDNESDAY...
HOWEVER WITH UPPER LOW CURRENTLY OFF THE CALIFORNIA COAST MOVING
INTO THE CENTRAL ROCKIES DURING THE DAY...MID LEVEL HEIGHT FALLS
AND A POTENTIAL LEAD SHORT WAVE/ JET STREAK SHOULD HELP ERODE THE
CAP ENOUGH FOR SOME STORMS TO DEVELOP ALONG THE DRY LINE FROM
CENTRAL KS INTO NORTHERN OK. MOST LIKELY TIME WOULD BE 21-00Z
HOWEVER EARLIER RUNS OF THE NAM HAVE SHOWN SOME EARLIER
DEVELOPMENT THAN THAT. WIND PROFILES SUGGEST THAT ONCE A STORM
DEVELOPS IT WILL QUICKLY BECOME SUPERCELLULAR AND POSE A THREAT
FOR VERY LARGE GAIL AND DAMAGING WINDS...AND SOME DEGREE OF
TORNADO POTENTIAL. OVERALL STORM COVERAGE IS EXPECTED TO REMAIN
FAIRLY LIMITED THROUGH WED NIGHT DUE TO PERSISTENT CAP ISSUES.
MAIN UPPER SYSTEM CONTINUES TO PROGRESS EAST THURSDAY WITH A COLD
FRONT OVERTAKING THE DRY LINE AND LIKELY PUSHING THROUGH PARTS OF
NE OKLAHOMA BY EARLY AFTERNOON. CONTINUED MOIST AND VERY UNSTABLE
AHEAD OF THE FRONT WITH MORE WIDESPREAD THUNDERSTORMS LIKELY THU
AFTERNOON AND EVENING MAINLY OVER SOUTHEAST OK AND NORTHWEST AR.
SHEAR PROFILES SUGGEST A MORE LINEAR STORM MODE AT THIS TIME.
STORMS WILL END THU EVENING WITH A COOLER AND STABLE AIRMASS
SETTLING OVER THE AREA FRIDAY.
ANOTHER UPPER LEVEL SYSTEM WILL MOVE IN FROM THE WEST BY THIS
WEEKEND AND WITH THE PRESENCE OF A SFC BOUNDARY IN THE AREA...
THUNDERSTORM CHANCES WILL RETURN BY SATURDAY AND CONTINUE INTO
EARLY NEXT WEEK. GENERAL CONSENSUS IS THIS UPPER LOW WILL
ULTIMATELY TACK A MUCH MORE SOUTHERLY TRACK...ANY SEVERE WEATHER
THREATS DURING THIS TIME REMAIN EXTREMELY UNCERTAIN.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...06
AREA FORECAST DISCUSSION
NWS NORMAN OK
336 PM CDT MON APR 6 2015
.DISCUSSION...
CONVECTION...
THE HRRR AND RAP HAVE SHOWN A RELATIVELY CONSISTENT SIGNAL OF
ISOLATED STORM/S/ DEVELOPING IN THE SOUTHWEST LATE THIS AFTERNOON.
MESOANALYSIS SHOW CONVECTIVE INHIBITION DECEASING ACROSS NORTHWEST
TEXAS. IT IS NOT A SURE THING THAT ANY STORM WILL DEVELOP AND
COVERAGE WILL BE LIMITED IF STORMS DO DEVELOP. BUT THERMODYNAMIC
PROFILE SHOWS QUITE AN UNSTABLE ATMOSPHERE... SO SEVERE WEATHER
WOULD BE LIKELY IF A STORM DOES INDEED DEVELOP. WILL KEEP POPS
BELOW 20 BUT ADD ISOLATED THUNDER IN THE WEATHER GRIDS IN TO COVER
THE POTENTIAL DEVELOPMENT. MUCH THE SAME SCENARIO IS EXPECTED
TOMORROW WITH AN UNSTABLE BUT GENERALLY CAPPED ATMOSPHERE WITHOUT
SIGNIFICANT FORCING... BUT CONVECTIVE INHIBITION DECREASES ENOUGH
THAT ISOLATED STORMS ARE POSSIBLE AGAIN IN THE LATE AFTERNOON AND
EARLY EVENING.
WEDNESDAY STILL LOOKS TO HAVE A MORE SIGNIFICANT SEVERE WEATHER
POTENTIAL AS THE TROUGH THAT IS CURRENTLY LOCATED OFF THE PACIFIC
COAST MOVES TOWARD THE HIGH PLAINS. WE EXPECT STORMS TO DEVELOP
WEDNESDAY AFTERNOON OR EVENING NEAR THE DRYLINE AND SPREAD EAST
WITH A DECENT CHANCE OF SEVERE WEATHER. THE STORM CHANCES WILL
LINGER INTO THURSDAY IN THE SOUTHEAST UNTIL THE SURFACE FRONT
MOVES THROUGH.
AFTER A BRIEF RESPITE FRIDAY...ANOTHER UPPER TROUGH APPROACHES
THIS WEEKEND INCREASING STORM CHANCES AGAIN THIS WEEKEND. EVEN AS
THE FIRST TROUGH MOVES BY THE PLAINS... THE MEAN TROUGH WILL
PERSIST IN THE WEST ALLOWING CONTINUED STORM CHANCES THROUGH
MONDAY.
FIRE WEATHER...
GUSTY POST-DRYLINE WINDS HAVE SPREAD INTO NORTHWESTERN OKLAHOMA
ALONG WITH TEMPERATURES IN THE LOWER 90S AND HUMIDITY IN THE
SINGLE DIGITS AND TEENS.... SO THE CURRENT RED FLAG WARNING LOOKS
GOOD INTO THE EARLY EVENING. ALTHOUGH WE WILL HAVE THE HEAT AND
LOW HUMIDITY AGAIN TOMORROW... WINDS ARE EXPECTED TO BE LIGHTER.
WINDS LOOK HIGHER AGAIN ON WEDNESDAY SO THE FIRE WEATHER WATCH IS
STILL VALID.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 63 84 66 82 / 10 20 20 30
HOBART OK 58 87 64 86 / 10 10 10 20
WICHITA FALLS TX 64 87 66 88 / 10 20 10 30
GAGE OK 51 88 53 85 / 10 0 10 10
PONCA CITY OK 61 87 64 85 / 10 20 20 40
DURANT OK 67 80 68 81 / 10 10 10 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR OKZ004-005-009-
010-014>016-021-033-034.
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR OKZ004>006-009>011-014>016-021-022-033>037.
TX...FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR TXZ083>085-087-088.
&&
$$
AREA FORECAST DISCUSSION
NWS MEDFORD OR
858 PM PDT TUE APR 7 2015
.DISCUSSION...THE CLOSED LOW PRESSURE HAS MOVED INTO NW
CALIFORNIA. THIS LOW WILL CONTINUE TO MOVE TO THE E-SE AND THE
CENTER IS EXPECTED TO BE IN NORTHERN NEVADA BY LATE TONIGHT.
SATELLITE IMAGERY SHOWS CONTINUED UPSLOPE PRECIPITATION INTO THE
WARNER MOUNTAINS AS WELL AS THE EAST SLOPES OF THE CASCADES. SHORT
TERM HIGH RESOLUTION MODELS CONTINUE TO PAINT SNOW SHOWERS ACROSS
THE WARNERS AS WELL AS THE MOUNTAINS OF EASTERN KLAMATH COUNTY,
WHILE ROADCAMS CONTINUE TO SHOW SNOW SHOWERS OVER THE CASCADES
PASSES. WILL KEEP THE CURRENT SUITE OF WINTER WEATHER ADVISORIES
GOING THROUGH THE NIGHT.
NEW MODEL RUNS SHOW NO BIG DEPARTURE FROM THE PREVIOUS FORECAST SO
NO UPDATES WILL ISSUED THIS EVENING. /FB
&&
.AVIATION...FOR THE 08/00Z TAF CYCLE...THIS EVENING THROUGH EARLY
WEDNESDAY MORNING...EXPECT MVFR CIGS/VISIBILITY FROM THE
CASCADES EASTWARD...WITH AREAS OF IFR IN LIGHT TO OCCASIONALLY
MODERATE SNOW SHOWERS. TERRAIN OBSCURATION WILL BE WIDESPREAD.
WEST OF THE CASCADES...EXPECT A MIX OF VFR/MVFR CIGS IN ISO/SCT
SHOWERS WITH MOUNTAINS OBSCURED. CONDITIONS WILL LIKELY IMPROVE TO
VFR FOR MOST AREAS MID TO LATE MORNING WEDNESDAY, THOUGH ISOLATED
SHOWERS WILL PERSIST. SPILDE
&&
.MARINE...UPDATED 400 PM PDT TUESDAY APR 07 2015...MAINLY LIGHT
WINDS AND LOW SEAS ARE EXPECTED TONIGHT THROUGH THURSDAY NIGHT AS
HIGH PRESSURE BUILDS INTO THE WATERS. A COLD FRONT WILL MOVE
THROUGH LATE FRIDAY OR FRIDAY NIGHT WITH SLIGHTLY HIGHER WINDS AND
SEAS. A LARGER WESTERLY SWELL WILL ARRIVE LATER SATURDAY NIGHT AND
PERSIST THROUGH MONDAY. SPILDE
&&
.PREV DISCUSSION... /ISSUED 500 PM PDT TUE APR 7 2015/
SHORT TERM...THE UPPER LOW CURRENTLY OFF THE COAST IN NORTHWEST
CAL IS MOVING SOUTH. WET SNOW CONTINUES IN SISKIYOU COUNTY, BUT
IT`S BECOMING SHOWERY AND ROADS ARE WET. THE MODELS ARE IN PRETTY
GOOD AGREEMENT SHOWING A DEFORMATION ZONE OF PRECIPITATION SETTING
UP EAST OF THE CASCADES LATER THIS EVENING AND LASTING INTO
WEDNESDAY MORNING, BUT DIFFER SLIGHTLY ON THE PLACEMENT OF THE
CORE OF HEAVIEST QPF. THE LATEST HRRR SHOWS THE DEFORMATION ZONE
WELL AND THE FORECAST FOR TONIGHT WILL LEAN TOWARDS THAT SOLUTION.
GIVEN THAT THIS WILL SET UP AT NIGHT, THERE WILL BE AN OPPORTUNITY
FOR SNOW TO ACCUMULATE ON ROADS DURING THE OVERNIGHT HOURS FOR
MOST AREAS EAST OF THE CASCADES. THE CASCADES WILL ALSO GET
ACCUMULATING SNOW TONIGHT, THUS HAVE EXTENDED THE END TIME OF THE
WINTER WEATHER ADVISORY UNTIL WEDNESDAY MORNING. DETAILS CAN BE
FOUND AT WSWMFR. GIVEN THE ABOVE MENTIONED SCENARIO, HAVE
INCREASED POPS...QPF AND SNOW AMOUNTS SIGNIFICANTLY, BUT IT STILL
MAY NOT BE ENOUGH. LATER SHIFTS MAY NEED TO TAKE ANOTHER LOOK AT
THIS AND ADJUST AMOUNTS HIGHER IF LATER MODEL RUNS CONTINUE TO
SHOW THE HIGHER QPF AMOUNTS.
WEDNESDAY WILL BE A TRANSITION DAY WITH THE DEFORMATION ZONE
WEAKENING IN THE MORNING. RAIN AND MOUNTAIN SNOW SHOWERS WILL
CONTINUE IN THE AFTERNOON, BUT SNOW LEVELS WILL COME UP TO AROUND
5000 FEET IN THE AFTERNOON, SO NOT EXPECTING MUCH IF ANY
ACCUMULATIONS FROM ABOUT MID MORNING WEDNESDAY ON DUE TO WARMING
ROAD TEMPERATURES AND SPOTTY PRECIPITATION.
DRY AND MILDER WEATHER FINALLY RETURNS THURSDAY AND CONTINUES INTO
THURSDAY NIGHT WITH SHORTWAVE RIDGING BUILDING INTO THE AREA.
MOST OF FRIDAY WILL BE DRY, THEN THE NEXT FRONT WILL REACH THE
COAST TOWARDS FRIDAY EVENING. THE GFS AND NAM ARE SLOWER WITH THE
ARRIVAL OF THE FRONT WHILE THE EC IS FASTER. FOR NOW WENT WITH A
BLEND BETWEEN THE TWO, BUT THE UPPER FLOW IS WEST OT NORTHWEST
WHICH NORMALLY LEADS TO QUICKER ARRIVAL TIMES OF FRONTS.
-PETRUCELLI
LONG TERM...THE ACTIVE PATTERN CONTINUES IN THE LONG TERM WITH
ANOTHER FRONTAL BOUNDARY MOVING INTO THE AREA LATE FRIDAY NIGHT
INTO SATURDAY MORNING. THE MODELS ARE IN FAIRLY GOOD AGREEMENT
THROUGH THE LONG TERM. THE EC IS A BIT FASTER TO PUSH THE FRONT
INLAND ON SATURDAY COMPARED TO THE GFS BUT BOTH MODELS HAVE IT
PUSHED THROUGH THE AREA BY LATE SATURDAY NIGHT. ZONAL FLOW WILL
SET UP FOR SUNDAY AND THE GFS IS HINTING AT SOME UPSLOPE SHOWERS
CONTINUING ALONG THE CASCADES THROUGH SUNDAY AFTERNOON. THERE MAY
ALSO BE SOME LINGERING SHOWERS FOR THE NORTHERN PORTION OF THE
CWA...MAINLY FROM THE UMPQUA DIVIDE NORTH. OTHERWISE, SUNDAY LOOKS
TO BE THE DRIEST DAY, RELATIVELY, THROUGH THE EXTENDED TERM. BY
MONDAY MORNING, THE MODELS ARE SLIGHTLY DIFFERENT IN THE TIMING
AND STRENGTH OF THE NEXT SYSTEM TO MOVE THROUGH. THE GFS IS FASTER
AND DEEPER WITH THE NEXT TROUGH, MEANING COOLER TEMPERATURES AND
LOWER SNOW LEVELS COMPARED TO THE EC...WHICH IS SLOWER BY ABOUT 12
HOURS AND NOT AS DEEP WITH THE TROUGH. EITHER WAY, IT LOOKS LIKE
UNSETTLED WEATHER WILL CONTINUE THROUGH THE END OF THE EXTENDED
TERM. MND
AVIATION...FOR THE 08/00Z TAF CYCLE...THIS EVENING THROUGH EARLY
WEDNESDAY MORNING...EXPECT MVFR CIGS/VISIBILITY FROM THE
CASCADES EASTWARD...WITH AREAS OF IFR IN LIGHT TO OCCASIONALLY
MODERATE SNOW SHOWERS. TERRAIN OBSCURATION WILL BE WIDESPREAD.
WEST OF THE CASCADES...EXPECT A MIX OF VFR/MVFR CIGS IN ISO/SCT
SHOWERS WITH MOUNTAINS OBSCURED. CONDITIONS WILL LIKELY IMPROVE TO
VFR FOR MOST AREAS MID TO LATE MORNING WEDNESDAY, THOUGH ISOLATED
SHOWERS WILL PERSIST. SPILDE
MARINE...UPDATED 500 PM PDT TUESDAY APR 07 2015...MAINLY LIGHT
WINDS AND LOW SEAS ARE EXPECTED TONIGHT THROUGH THURSDAY NIGHT AS
HIGH PRESSURE BUILDS INTO THE WATERS. A COLD FRONT WILL MOVE
THROUGH LATE FRIDAY OR FRIDAY NIGHT WITH SLIGHTLY HIGHER WINDS AND
SEAS. A LARGER WESTERLY SWELL WILL ARRIVE LATER SATURDAY NIGHT AND
PERSIST THROUGH MONDAY. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 9 AM PDT WEDNESDAY FOR
ORZ029>031-624-625.
WINTER WEATHER ADVISORY UNTIL 9 AM PDT WEDNESDAY FOR
ORZ027-028-617-621-623.
CA...WINTER WEATHER ADVISORY UNTIL 9 AM PDT WEDNESDAY FOR CAZ085-285.
PACIFIC COASTAL WATERS...NONE.
$$
FJB/CC/MAS
AREA FORECAST DISCUSSION...UPDATED
NWS MEDFORD OR
500 PM PDT TUE APR 7 2015
UPDATED AVIATION AND MARINE SECTIONS
.SHORT TERM...THE UPPER LOW CURRENTLY OFF THE COAST IN NORTHWEST
CAL IS MOVING SOUTH. WET SNOW CONTINUES IN SISKIYOU COUNTY, BUT
IT`S BECOMING SHOWERY AND ROADS ARE WET. THE MODELS ARE IN PRETTY
GOOD AGREEMENT SHOWING A DEFORMATION ZONE OF PRECIPITATION SETTING
UP EAST OF THE CASCADES LATER THIS EVENING AND LASTING INTO
WEDNESDAY MORNING, BUT DIFFER SLIGHTLY ON THE PLACEMENT OF THE
CORE OF HEAVIEST QPF. THE LATEST HRRR SHOWS THE DEFORMATION ZONE
WELL AND THE FORECAST FOR TONIGHT WILL LEAN TOWARDS THAT SOLUTION.
GIVEN THAT THIS WILL SET UP AT NIGHT, THERE WILL BE AN OPPORTUNITY
FOR SNOW TO ACCUMULATE ON ROADS DURING THE OVERNIGHT HOURS FOR
MOST AREAS EAST OF THE CASCADES. THE CASCADES WILL ALSO GET
ACCUMULATING SNOW TONIGHT, THUS HAVE EXTENDED THE END TIME OF THE
WINTER WEATHER ADVISORY UNTIL WEDNESDAY MORNING. DETAILS CAN BE
FOUND AT WSWMFR. GIVEN THE ABOVE MENTIONED SCENARIO, HAVE
INCREASED POPS...QPF AND SNOW AMOUNTS SIGNIFICANTLY, BUT IT STILL
MAY NOT BE ENOUGH. LATER SHIFTS MAY NEED TO TAKE ANOTHER LOOK AT
THIS AND ADJUST AMOUNTS HIGHER IF LATER MODEL RUNS CONTINUE TO
SHOW THE HIGHER QPF AMOUNTS.
WEDNESDAY WILL BE A TRANSITION DAY WITH THE DEFORMATION ZONE
WEAKENING IN THE MORNING. RAIN AND MOUNTAIN SNOW SHOWERS WILL
CONTINUE IN THE AFTERNOON, BUT SNOW LEVELS WILL COME UP TO AROUND
5000 FEET IN THE AFTERNOON, SO NOT EXPECTING MUCH IF ANY
ACCUMULATIONS FROM ABOUT MID MORNING WEDNESDAY ON DUE TO WARMING
ROAD TEMPERATURES AND SPOTTY PRECIPITATION.
DRY AND MILDER WEATHER FINALLY RETURNS THURSDAY AND CONTINUES INTO
THURSDAY NIGHT WITH SHORTWAVE RIDGING BUILDING INTO THE AREA.
MOST OF FRIDAY WILL BE DRY, THEN THE NEXT FRONT WILL REACH THE
COAST TOWARDS FRIDAY EVENING. THE GFS AND NAM ARE SLOWER WITH THE
ARRIVAL OF THE FRONT WHILE THE EC IS FASTER. FOR NOW WENT WITH A
BLEND BETWEEN THE TWO, BUT THE UPPER FLOW IS WEST OT NORTHWEST
WHICH NORMALLY LEADS TO QUICKER ARRIVAL TIMES OF FRONTS.
-PETRUCELLI
.LONG TERM...THE ACTIVE PATTERN CONTINUES IN THE LONG TERM WITH
ANOTHER FRONTAL BOUNDARY MOVING INTO THE AREA LATE FRIDAY NIGHT
INTO SATURDAY MORNING. THE MODELS ARE IN FAIRLY GOOD AGREEMENT
THROUGH THE LONG TERM. THE EC IS A BIT FASTER TO PUSH THE FRONT
INLAND ON SATURDAY COMPARED TO THE GFS BUT BOTH MODELS HAVE IT
PUSHED THROUGH THE AREA BY LATE SATURDAY NIGHT. ZONAL FLOW WILL
SET UP FOR SUNDAY AND THE GFS IS HINTING AT SOME UPSLOPE SHOWERS
CONTINUING ALONG THE CASCADES THROUGH SUNDAY AFTERNOON. THERE MAY
ALSO BE SOME LINGERING SHOWERS FOR THE NORTHERN PORTION OF THE
CWA...MAINLY FROM THE UMPQUA DIVIDE NORTH. OTHERWISE, SUNDAY LOOKS
TO BE THE DRIEST DAY, RELATIVELY, THROUGH THE EXTENDED TERM. BY
MONDAY MORNING, THE MODELS ARE SLIGHTLY DIFFERENT IN THE TIMING
AND STRENGTH OF THE NEXT SYSTEM TO MOVE THROUGH. THE GFS IS FASTER
AND DEEPER WITH THE NEXT TROUGH, MEANING COOLER TEMPERATURES AND
LOWER SNOW LEVELS COMPARED TO THE EC...WHICH IS SLOWER BY ABOUT 12
HOURS AND NOT AS DEEP WITH THE TROUGH. EITHER WAY, IT LOOKS LIKE
UNSETTLED WEATHER WILL CONTINUE THROUGH THE END OF THE EXTENDED
TERM. MND
&&
.AVIATION...FOR THE 08/00Z TAF CYCLE...THIS EVENING THROUGH EARLY
WEDNESDAY MORNING...EXPECT MVFR CIGS/VISIBILITY FROM THE
CASCADES EASTWARD...WITH AREAS OF IFR IN LIGHT TO OCCASIONALLY
MODERATE SNOW SHOWERS. TERRAIN OBSCURATION WILL BE WIDESPREAD.
WEST OF THE CASCADES...EXPECT A MIX OF VFR/MVFR CIGS IN ISO/SCT
SHOWERS WITH MOUNTAINS OBSCURED. CONDITIONS WILL LIKELY IMPROVE TO
VFR FOR MOST AREAS MID TO LATE MORNING WEDNESDAY, THOUGH ISOLATED
SHOWERS WILL PERSIST. SPILDE
&&
.MARINE...UPDATED 500 PM PDT TUESDAY APR 07 2015...MAINLY LIGHT
WINDS AND LOW SEAS ARE EXPECTED TONIGHT THROUGH THURSDAY NIGHT AS
HIGH PRESSURE BUILDS INTO THE WATERS. A COLD FRONT WILL MOVE
THROUGH LATE FRIDAY OR FRIDAY NIGHT WITH SLIGHTLY HIGHER WINDS AND
SEAS. A LARGER WESTERLY SWELL WILL ARRIVE LATER SATURDAY NIGHT AND
PERSIST THROUGH MONDAY. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 9 AM PDT
WEDNESDAY FOR ORZ029>031-624-625.
WINTER WEATHER ADVISORY UNTIL 9 AM PDT WEDNESDAY FOR
ORZ027-028-617-621-623.
CA...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 9 AM PDT
WEDNESDAY FOR CAZ085-285.
PACIFIC COASTAL WATERS...NONE.
$$
MAS/MAP/MND
AREA FORECAST DISCUSSION
NWS MEDFORD OR
1000 AM PDT MON APR 6 2015
.DISCUSSION...A FEW ADJUSTMENTS WERE MADE TO THE FORECAST TODAY,
BUT THE OVERALL IDEA PRESENTED IN THE PREVIOUS DISCUSSION REMAINS
VALID. THE NAM...GFS AND HRRR MODELS SHOWS THE CORE OF THE HEAVIER
PRECIPIATION FOR CURRY...COOS AND JOSEPHINE COUNTY. AS THE LOW
DEVELOPS AND MOVES SOUTH THE CORE OF HEAVIER PRECIPIATION WILL BE
ALIGNED FROM SOUTH TO NORTH ALONG THE COAST AND SPOTTY FURTHER
INLAND. WE`LL GET DOWNSLOPED IN THE ROGUE VALLEY TODAY, SO IT`S
POSSIBLE WE DON`T GET ANY RAIN DURING THE DAY. HOWEVER WINDS ARE
EXPECTED TO INCREASE WITH THE STRONGEST WINDS NEAR ASHLAND THIS
AFTERNOON AND EVENING.
REGARDING TONIGHT...THE NAM AND GFS HAVE TRENDED SLOWER WITH THE
EASTWARD PROGRESSION OF THE HEAVY PRECIPITATION IN NORTHERN CAL
AND MOUNT SHASTA REGION, BUT ALL SIGNS ARE STILL POINTING TOWARDS
A HEAVY WET SNOW EVENT OVERNIGHT TONIGHT INTO TUESDAY MORNING. THE
LATER ARRIVAL COULD RESULT IN LESS SNOW ACCUMULATIONS, BUT IT WILL
STILL BE CONSIDERED A HIGH IMPACT EVENT. -PETRUCELLI
&&
.AVIATION...AT THE COAST...MVFR CIGS ARE EXPECTED WITH LOCAL IFR
CIGS POSSIBLE LATE THIS MORNING INTO THIS EVENING AS A STRONG
FRONTAL BOUNDARY MOVES INLAND. INLAND WESTSIDE...VFR CONDITIONS
ARE EXPECTED INTO THIS EVENING. HOWEVER MVFR CIGS ARE POSSIBLE IN
THE ILLINOIS VALLEY AND JUST WEST OF ROSEBURG WITH MOUNTAINS
PARTLY OBSCURED IN CLOUDS AND SHOWERS. EAST OF THE CASCADES...VFR
CONDITIONS WILL CONTINUE INTO EARLY AFTERNOON. RAIN/SNOW WILL
BEGIN TO AFFECT THE EAST SIDE AND NORCAL LATE THIS AFTERNOON WITH
DETERIORATING CONDITIONS. -PETRUCELLI
&&
.MARINE...UPDATED 300 AM PDT MONDAY APR 2015...UNSETTLED WEATHER
WITH ISOLATED THUNDERSTORMS WILL CONTINUE TODAY. A STRONG LOW
PRESSURE WILL MOVE INTO THE WATERS MONDAY. SOUTHEAST WINDS WILL
INCREASE TO ADVISORY LEVELS THIS MORNING WITH GALES LIKELY IN THE
OUTER WATERS AND PARTS OF THE INNER WATERS SOUTH OF CAPE BLANCO. THE
STRONGER WINDS NEAR THE LOW WILL PRODUCE CHAOTIC AND VERY STEEP SEAS
AS IT MOVES NORTH ALONG THE WESTERN BORDER OF THE WATERS. THE CENTER
OF THE LOW WILL BE AROUND 60 NM OFFSHORE FROM CAPE BLANCO BY EARLY
THIS EVENING. THE LOW WEAKENS TONIGHT THEN MOVES INLAND TUESDAY.
A WEAK HIGH PRESSURE IS EXPECTED THROUGH LATE IN THE WEEK. /FB
&&
.PREV DISCUSSION... /ISSUED 414 AM PDT MON APR 6 2015/
DISCUSSION...
***A SIGNIFICANT SPRING SNOWSTORM WILL IMPACT PORTIONS OF
NORTHERN CALIFORNIA TONIGHT THROUGH TUESDAY MORNING***
A STRONG UPPER LEVEL LOW PRESSURE SYSTEM NEAR 44N AND 130W WILL
CONTINUE TO DROP SOUTH-SOUTHEASTWARD OFF THE OREGON COAST TODAY.
A VIGOROUS SHORT WAVE WILL DIG IN ON THE BACK SIDE OF THE UPPER
LOW AND THIS WILL SPAWN A SIGNIFICANT SURFACE LOW WHICH WILL MOVE
TO THE SOUTHERN PORTION OF OUR COASTAL WATERS BY THIS AFTERNOON.
SHOWERS ARE OCCURRING THIS MORNING, MAINLY ALONG AND WEST OF THE
CASCADES WITH ISOLATED THUNDERSTORMS ALONG THE COAST AND JUST
INLAND. AS THE SURFACE LOW DEVELOPS...A BAND OF MODERATE TO HEAVY
PRECIPITATION WILL TAKE AIM AT THE SOUTHWEST OREGON COAST AND
PORTIONS OF NORTHERN CALIFORNIA (MAINLY FROM ABOUT MOUNT SHASTA
WESTWARD) THIS AFTERNOON. PRECIPITATION WILL BE MUCH SPOTTIER EAST
OF THE CASCADES AS STRENGTHENING MID-LEVEL FLOW IN ADVANCE OF
THIS SYSTEM BACKS TO THE SOUTH.
DESPITE THE LACK OF A STRONG PRESSURE GRADIENT...RDD-MFR IS ABOUT
4 MB...700MB WINDS OF 50-55KT WILL CAUSE STRONG, GUSTY WINDS
THROUGH THE SHASTA VALLEY LATER THIS MORNING THROUGH LATE
TONIGHT...AND A WIND ADVISORY IS UP AT NPWMFR. DON`T THINK WINDS
WILL REACH ADVISORY LEVELS HERE IN THE ROGUE VALLEY...BUT THERE
MAY BE SOME GUSTS TO 35 OR 40 MPH ON THE SOUTH END NEAR TALENT
AND ASHLAND.
THE STRONG 700MB FLOW IN CONCERT WITH GOOD MOISTURE TRANSPORT AND
SUFFICIENT UPWARD MOTION WILL BRING A SIGNIFICANT UPSLOPE
PRECIPITATION EVENT TO PORTIONS OF NORTHERN CALIFORNIA TONIGHT AND
CONTINUE THROUGH TUESDAY MORNING. SOME MINOR TIMING DIFFERENCES
STILL EXIST IN THE MODEL GUIDANCE THIS MORNING, BUT ALL SIGNS
STILL POINT TO A HIGH IMPACT SNOW EVENT IN AND AROUND MOUNT SHASTA
CITY. MODEL 850 TEMPS ARE ABOUT -2 TO -3C AND 1000-700MB THICKNESS
VALUES BELOW 2840M SHOULD RESULT IN HEAVY, WET SNOW ALONG
INTERSTATE 5 SOUTH OF WEED. THE SNOW LEVEL WILL LIKELY LOWER DOWN
TO ~2000-2500 FEET (TO INCLUDE DUNSMUIR). WINTER STORM WARNINGS
ARE IN EFFECT AND EXPECTED SNOW ACCUMULATIONS CAN BE VIEWED AT
WSWMFR.
WITH SUCH STRONG MID-LEVEL WINDS, THERE WILL BE SOME DOWNSLOPING
IN THE VALLEYS WEST OF THE CASCADES TODAY INTO THIS EVENING, SO
IT MAY TAKE A WHILE FOR PRECIPITATION TO REACH MEDFORD. THERE
SHOULD BE A PERIOD OF RAIN OVERNIGHT INTO TUESDAY MORNING. THERE
WILL ALSO BE SOME SNOW ACROSS THE CASCADES TO THE EAST SIDE AND
THE REST OF NORTHERN CALIFORNIA OVERNIGHT INTO TUESDAY...BUT
ACCUMULATIONS IN THOSE AREAS WILL BE MOSTLY LIGHT. A SPECIAL
WEATHER STATEMENT HAS BEEN ISSUED AT SPSMFR TO HIGHLIGHT AREAS
WHERE SNOW COVERED OR SLUSHY ROADS MAY BE A TRAVEL IMPACT.
UPSLOPE FLOW WILL END BY LATE TUESDAY MORNING AND THE UPPER
TROUGH/LOW WILL MOVE INTO NORTHERN CALIFORNIA. THIS WILL STILL
KEEP SHOWERS GOING ACROSS THE AREA. ENOUGH INSTABILITY MAY TRIGGER
ISOLATED THUNDERSTORMS AS WELL, MAINLY ALONG AND EAST OF THE
CASCADES. A SHORT WAVE ON THE BACK SIDE OF THE TROUGH WILL KEEP A
CHANCE OF SHOWERS IN THE FORECAST FOR WEDNESDAY, BUT THESE SHOULD
BE LESS NUMEROUS THAN ON TUESDAY. A RIDGE WILL FINALLY BRING AN
END TO THE UNSETTLED WEATHER LATER WEDNESDAY NIGHT THROUGH
THURSDAY. SPILDE
EXTENDED FORECAST FROM SUNDAY AFTERNOON`S AFD...NO CHANGES...THE
UPPER LEVEL FLOW OVER THE WEST COAST WILL BECOME SPLIT ON FRIDAY
WITH A CLOSED LOW EXPECTED TO APPROACH NORTHERN CALIFORNIA BUT
REMAIN OFFSHORE. IT IS EXPECTED TO TRACK SOUTH-SOUTHEAST TO
SOUTHERN CALIFORNIA FRIDAY NIGHT AND SATURDAY. MEANTIME, AN UPPER
TROUGH IN THE NORTHERN BRANCH WILL MOVE EAST TO THE BRITISH
COLUMBIA COAST. TO A LARGE EXTENT, OUR AREA WILL BE BETWEEN THE
BRANCHES ON FRIDAY WITH CONDITIONS LIKELY TO RESEMBLE THOSE FROM
THURSDAY...SLIGHTLY WARMER BUT WITH CONTINUED SCATTERED TO BROKEN
HIGH CLOUDS. THE EXTENT TO WHICH CONDITIONS MAY BE DIFFERENT IS
THAT THE ECMWF SOLUTION IS FASTER THAN THE GFS WITH A VERY WEAK
WARM FRONT THAT MAY BRUSH NORTHERN DOUGLAS COUNTY LATE IN THE DAY.
FOR FRIDAY NIGHT INTO SATURDAY NIGHT, A MOIST ONSHORE FLOW IS LIKELY
INTO THE PACIFIC NORTHWEST WITH TEMPERATURES SLIGHTLY BELOW NORMAL.
THE TIMING AND TRACK OF A SERIES OF WEAK DISTURBANCES IS UNCERTAIN.
THE ECMWF REMAINS FASTER AND IS A COLDER AND WETTER SOLUTION, BUT
NEITHER MODEL IS PARTICULARLY STRONG. THE ECMWF INDICATES WEST SIDE
FOCUSED PRECIPITATION OF 0.05 TO 0.25 INCHES WHILE THE GFS INDICATES
ONLY UP TO 0.05 INCHES. ON SUNDAY, DAY 7, THE ECMWF REMAINS MORE
AMPLIFIED WITH THE UPPER LEVEL PATTERN AS IT INDICATES A STRONGER
RIDGE THAN THE GFS. /DW
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER STORM WARNING FROM 5 PM THIS AFTERNOON TO 11 AM PDT
TUESDAY ABOVE 3000 FEET FOR FOR ORZ621.
CA...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM PDT
TUESDAY FOR CAZ081-281.
WIND ADVISORY UNTIL 2 AM PDT TUESDAY FOR CAZ081-281.
WINTER STORM WARNING FROM 5 PM THIS AFTERNOON TO 11 AM PDT
TUESDAY ABOVE 3000 FEET FOR FOR CAZ080-280.
WINTER STORM WARNING FROM 5 PM THIS AFTERNOON TO 11 AM PDT
TUESDAY FOR CAZ082-282.
WINTER STORM WARNING FROM 5 PM THIS AFTERNOON TO 11 AM PDT
TUESDAY FOR CAZ083-284.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
PZZ356.
HAZARDOUS SEAS WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT
THIS EVENING FOR PZZ356-370-376.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 11 PM PDT THIS EVENING
FOR PZZ356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ350-356-370.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
PZZ350-370.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT THIS MORNING FOR
PZZ376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT THIS
MORNING FOR PZZ376.
$$
MAP/MAP/MAP
AREA FORECAST DISCUSSION
NWS PORTLAND
923 PM PDT SUN APR 5 2015
.SYNOPSIS...UPPER LOW OFF THE OREGON COAST WILL SLOWLY PUSH INTO N
CALIF MONDAY AND TUESDAY...AND MAINTAIN A THREAT OF SHOWERS FOR NW
OREGON AND SW WASHINGTON. HIGH PRESSURE WILL BUILD OVER THE PACIFIC
NORTHWEST WEDNESDAY AND THURSDAY FOR DRY AND MILD WEATHER. A COLD
FRONT MAY BRING A RETURN OF RAIN AND MOUNTAIN SNOW NEXT WEEKEND.
&&
.SHORT TERM...THE THUNDERSTORMS THIS AFTERNOON QUICKLY LOST STEAM
THIS EVENING AS THE SURFACE TEMPERATURES COOLED. SATELLITE AND RADAR
SHOW SHOWERS CONTINUING OVER THE REGION AS AN UPPER LOW CIRCULATES
JUST OFFSHORE THE NORTHERN OREGON COAST. THE UPPER LOW WILL CONTINUE
MOVING SOUTHWARD OFF OF THE OREGON COAST TONIGHT BEFORE PUSHING
ONSHORE OVER NORTHERN CALIFORNIA MONDAY AFTERNOON AND EVENING.
MODELS FORECAST THAT THE SHOWERS OVER THE PORTLAND FORECAST AREA
DECREASE TONIGHT FROM SOUTH TO NORTH AS THE LOW TRACKS SOUTHWARD. IF
THIS PANS OUT THEN MONDAY MORNING WILL BE WITH MOSTLY DRY WITH JUST
ISOLATED TO SCATTERED SHOWERS FOR THE HIGHER TERRAIN AND ALONG THE
IMMEDIATE COAST. HAVE LEANED TOWARDS THIS GUIDANCE WITH THE EVENING
UPDATE AND HAVE DECREASED POPS FOR THE INTERIOR LOW LANDS LATE
TONIGHT THROUGH MONDAY MORNING.
HOWEVER...SATELLITE SHOWS A BAND OF CONVECTIVE SHOWERS OFFSHORE OF THE
CALIFORNIA COAST THAT MAY SWING NORTHWARD OVER OREGON EARLY MONDAY
MORNING AND HAVE KEPT AT LEAST A SLIGHT CHANCE OF POPS FOR ALL
LOCATIONS. THE HRRR MODEL CURRENTLY CAPTURES THIS CONVECTIVE BAND THE
BEST AND FORECASTS THAT IT WILL WEAKEN AS IT NEARS THE PORTLAND
FORECAST AREA...BUT STILL SPREAD SOME SHOWERS ACROSS LANE COUNTY NEAR
SUNRISE...SO HAVE MAINTAINED CHANCE TO LIKELY POPS FOR LANE COUNTY
MONDAY MORNING.
THERE APPEARS TO BE ISOLATED ELEVATED THUNDERSTORMS WITH THIS BAND
THAT WILL NEED TO BE WATCHED CLOSELY OVERNIGHT...ALTHOUGH IT LOOKS
LIKE THEY WILL REMAIN SOUTH OF OREGON.
IT IS DIFFICULT TO FORECAST HOW MUCH IF ANY CLEARING WILL ACCOMPANY
THE DECREASE IN SHOWERS TONIGHT. SATELLITE IMAGERY SHOWS A LOT OF
CLOUDS ROTATING AROUND THE LOW...BUT WITH IT MOVING SOUTHWARD TONIGHT
IT IS POSSIBLE THAT SKIES MAY CLEAR FOR NW OREGON. WITH THE SHOWERS
THIS EVENING...MANY AREAS HAVE TEMPERATURE/DEW POINT DEPRESSIONS
WITHIN 5 DEGREES...AND WOULD NOT BE SURPRISED IF SOME PATCHY FOG
DEVELOPS IN AREAS WITH CLEARING.
SHOWER ACTIVITY WILL INCREASE ACROSS NW OREGON MONDAY AFTERNOON AND
EVENING AS THE UPPER LOW MOVES CLOSER TO THE S OR/N CA COAST. THE
POSITION OF THE LOW IS NOT VERY FAVORABLE FOR CONVECTION FOR THE
PORTLAND FORECAST AREA. HOWEVER...IF SUNSHINE IS ABUNDANT MONDAY
MORNING SUCH THAT THE SURFACE TEMPERATURES RISE TO NEAR 60 DEGREES
BEFORE THE ARRIVAL OF SHOWERS IN THE AFTERNOON...THEN A FEW
THUNDERSTORMS MAY DEVELOP. THE FORECAST CONFIDENCE FOR THUNDERSTORMS
IS NOT HIGH ENOUGH TO ADD A MENTION IN THE FORECAST THOUGH.
SHOWERS WRAPPING AROUND THE LOW WILL IMPACT THE REGION MONDAY NIGHT
AND TUESDAY MORNING AS THE LOW PUSHES FURTHER INLAND ACROSS
CALIFORNIA. SHOWERS WILL GRADUALLY DECREASE TUESDAY AS THE LOW MOVES
ACROSS NORTHERN NEVADA. TJ
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WEDNESDAY
NIGHT THROUGH SUNDAY...MODELS REMAIN IN FAIRLY GOOD AGREEMENT THAT AN
UPPER TROUGH AXIS WILL SET UP JUST OFFSHORE BY LATE WEDNESDAY. MAY
SEE A FEW SHOWERS IN THE HIGHER TERRAIN OF THE CASCADES BUT WEDNESDAY
NIGHT THROUGH EARLY FRIDAY SHOULD BE GENERALLY DRY FOR MOST LOCATIONS
ALONG WITH WARMING TEMPERATURES FOR THURSDAY...INTO THE MID 60S FOR
THE INTERIOR LOWLANDS AND AROUND 60 ALONG THE COAST. A FRONTAL SYSTEM
APPROACHES THE REGION SOMETIME FRIDAY TO BRING ANOTHER SHOT OF
PRECIPITATION AND COOLER AIR. SOME TIMING ISSUES IN THE LATEST
FORECAST MODELS...BUT CONTINUED THE FORECAST OF RAIN REACHING THE
COAST BY LATE FRIDAY AFTERNOON AND PUSHING INLAND EARLY FRIDAY NIGHT.
RAIN LIKELY CONTINUES INTO THE WEEKEND IN THE ONSHORE FLOW PATTERN
ALOFT. THIS FRONT WILL BRING SNOW LEVELS DOWN PERHAPS AS LOW AS
AROUND 3000 FT FOR SUNDAY WITH SOME...THOUGH PERHAPS
LIMITED...MOISTURE REMAINING. CULLEN
&&
.AVIATION...A LINE OF SHOWERS CURRENTLY EXTEND FROM SOUTH OF KTTD
NORTHWEST TO KAST AND CONTINUES OFFSHORE...WITH A SMALLER LINE
MOVING ONSHORE NEAR LINCOLN CITY AND EXTENDING EAST TO KSLE.
EXPECT THESE SHOWERS TO CONTINUE TO MOVE NORTH TO NORTHEAST OVER
THE NEXT SEVERAL HOURS. MOST TAF SITES WILL CONTINUE TO SEE VFR
CONDITIONS...WITH OCCASIONAL PERIODS OF REDUCED FLIGHT RULES UNDER
HEAVIER SHOWERS. THERE IS AN OUTSIDE CHANCE THAT INLAND TAF SITES
COULD SEE FOG/LOW STRATUS DEVELOP TONIGHT AFTER 08Z.
HOWEVER...WITH THE UPPER LEVEL LOW CONTINUING TO SPREAD SHOWERS
ONSHORE THERE COULD BE ENOUGH MIXING TO PREVENT IT. WIDESPREAD
SHOWERS LOOK TO RETURN TO CENTRAL OREGON AFTER 12Z TOMORROW
MORNING AND SPREAD NORTHWARD THROUGH THE DAY.
KPDX AND APPROACHES...EXPECT MOSTLY VFR CONDITIONS WITH OCCASIONAL
PERIODS OF MVFR CIGS AND VSBYS UNDER HEAVIER SHOWERS THROUGH
AROUND 08Z TONIGHT. AFTER A BRIEF BREAK...SHOWERS LOOK TO RETURN
AFTER 16Z TOMORROW MORNING. /64
&&
.MARINE...NO SIGNIFICANT CHANGES. PREVIOUS DISCUSSION
FOLLOWS...LOW PRES OFF THE WA AND OR COASTS WILL CONTINUE TO
DRIFT SOUTH AND STALL OFF THE NORTHERN CALIFORNIA COAST MONDAY AND
INTENSIFY. MODELS HAVE NOT HANDLED THE EVOLUTION OF THIS LOW VERY
WELL AS IT MOVES OFF THE NORTHERN CALIFORNIA COAST...BUT NOW HAVE
COME INTO BETTER AGREEMENT WITH TODAYS RUN. AT THIS POINT NO
ADVISORY OR WARNING WILL BE NEEDED FOR OUR FORECAST AREA. AT WORST
THERE COULD BE SMALL CRAFT ADVISORY WINDS SOUTH OF NEWPORT ON
MONDAY. THE LOW WEAKENS AND PUSHES ASHORE SOMEWHERE IN NORTHERN
CALIFORNIA ON TUE WITH HIGH PRES RETURNING TO THE WATERS FOR THE
MIDDLE OF NEXT WEEK.
SEAS CURRENTLY SITTING AT AROUND 8 FT. EXPECT SEAS TO CONTINUE
GRADUALLY SUBSIDING OVER THE NEXT COUPLE OF DAYS...REACHING NEAR 5
FT ON MON. /MH
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1054 PM EDT TUE APR 7 2015
.SYNOPSIS...
A STATIONARY FRONTAL BOUNDARY WILL REMAIN DRAPED WEST OF THE
APPALACHIAN MOUNTAINS THE NEXT COUPLE OF DAYS...WHILE HIGH
PRESSURE OVER THE CANADIAN MARITIMES NOSES SOUTHWESTWARD ACROSS
THE MID ATLANTIC REGION. A DEEP STORM SYSTEM WILL TRACK THROUGH
THE GREAT LAKES ON FRIDAY...DRAGGING A TRAILING COLD FRONT THROUGH
PENNSYLVANIA.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
RADAR TRENDS AND LATEST HRRR IMPLY AN INCREASING CHANCE OF RAIN
SHOWERS OVERNIGHT...AS NEXT SHORTWAVE AND ASSOC AREA OF LG SCALE
FORCING WORKS EASTWARD FROM THE LOWER GRT LKS. SFC ANALYSIS SHOWS BACK
DOOR COLD FRONT HAS PUSHED SOUTH OF THE MASON DIXON LINE LATE THIS
EVENING. A MOIST...EASTERLY FLOW NORTH OF THIS BOUNDARY WILL
PRODUCE OCNL DRIZZLE ACROSS CENTRAL PA LATER TONIGHT...IN
ADDITION TO THE SHRA ASSOC WITH APPROACHING SHORTWAVE. WILL
CONTINUE TO CARRY LIKELY POPS EVERYWHERE OVERNIGHT...ALTHOUGH
AMOUNTS ARE NOT EXPECTED TO BE SUBSTANTIAL. GENERALLY A TRACE TO A
FEW HUNDRETHS IN MOST AREAS...WITH UP TO A TENTH IN SOME
LOCATIONS.
1038 MB SFC HIGH SPREADING EASTWARD FROM ONTARIO TO QUEBEC WILL
INDUCE CAD ACROSS EASTERN PA OVERNIGHT WITH COOLER LLVL TEMPS
BLEEDING SOUTHWARD INTO WEDNESDAY MORNING. READINGS BY DAWN
SHOULD RANGE FROM THE U30S OVR THE HIGH TERRAIN NORTH AND EAST OF
KIPT...TO THE M40S OVR THE SOUTHERN COUNTIES.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
COOL AND DANK CONDITIONS WILL BE THE NORM ON WEDNESDAY IN CAD
REGIME WITH PLENTY OF LLVL MOISTURE AND OVERRUNNING ZONAL FLOW
ALOFT PROMOTING LIGHT SHOWERS ESPECIALLY IN THE AFTERNOON. HIGHS
WILL RANGE THROUGH THE 40S FOR MOST...BUT AREAS ALONG THE
ALLEGHENY FRONT MAY NUDGE INTO THE WARM SECTOR WITH WESTERN WARREN
AND WESTERN SOMERSET COUNTIES REACHING INTO THE 50S AND PERHAPS
NEAR 60 ACROSS SOUTHWEST SOMERSET COUNTY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
DID NOT CHANGE POPS OR WEATHER FOR WED NIGHT...GIVEN SLIGHT
CHANCE FOR A LITTLE FREEZING DRIZZLE OR RAIN ACROSS THE NE.
LOWS NEAR HUDSON AND JAMES BAY AREA WERE ZERO TO 20 BELOW
THIS MORNING. THAT IS COLD FOR EARLY APRIL.
DETAILS BELOW...
GIVEN THE FACT THAT WE/LL HAVE A 1040 MB SFC HIGH BECOMING PARKED
ACROSS SRN QUEBEC /WHERE CURRENT TEMPS ARE IN THE SINGLE DIGITS TO
TEENS/ AND 1000 MB AGEOSTROPHIC FLOW INCREASING FROM THE
NORTH-NORTHEAST /AND STAYING THERE FOR A 24-36 HOURS PERIOD/...WENT
SEVERAL DEG F BELOW MODEL TEMPS FOR WED MAXES AND WED NIGHT MINS.
EVEN MENTIONED A SLIGHT CHC FOR LIGHT FZRA ACROSS PARTS OF THE
NCENT MTNS AND WRN POCONOS LATE WED NIGHT AND EARLY THURSDAY.
THIS LLVL COLD AIR DAMMING LIKELY TO LINGER INTO THURSDAY AFT.
SOME NEW DETAIL BELOW...
WHILE TEMPS MAY NOT WARM REAL GOOD THU...AND I LEFT THEM
CLOSE TO WHAT WE HAD...WILL CONTINUE TO MONITOR. VERY TIGHT
TEMPERATURE GRADIENT AT 850 MB LATE WED EVENING ACROSS CENTRAL
NY...MINUS 4 TO PLUS 10 IN ABOUT 80 TO 100 MILE BAND.
ANYWAY...WARMER AIR WILL WORK INTO THE AREA LATE THU INTO
FRIDAY...AS LOW LEVEL WIND FIELDS INCREASE. WARMEST TEMPERATURES
MIGHT END UP BEING ACROSS WARREN COUNTY.
DID NOT UP TEMPS MUCH FOR FRIDAY...MODELS MOVE COLD FRONT ACROSS
THE AREA RATHER FAST.
SOME CHANCE OF A STRONG THUNDERSTORM ACROSS THE WEST LATER FRIDAY.
THIS BASED ON TIMING AND THE THERMAL RIDGE OVER THE BEST MOISTURE.
HAVE TO WATCH FOR SEVERE...BUT DYNAMICS LIKELY TO LIFT NE AWAY
FROM THE AREA. ALSO TIMING NOT THE BEST.
WHILE WE WILL SEE SOME SHOWERS EACH DAY THIS WEEK...NOT SEEING ANY
LARGE AMTS. THUS NOT SEEING ANY WIDESPREAD HYDRO CONCERNS AT THIS
POINT. ENJOY THE MILDER TEMPERATURES.
RATHER STRONG SMALL UPPER LEVEL TROUGH FOR LATE FRIDAY INTO SAT.
TOOK OUT SHOWERS AFTER EARLY FRIDAY EVENING. MAIN THING WAS TO
LOWER TEMPS FOR FRIDAY NIGHT INTO SAT...GIVEN AIRMASS TO THE NORTH
AND COLD ADVECTION.
WEEKEND SIMILAR TO LAST WEEKEND. BREEZY AND COOL ON SAT. WARMER
ON SUNDAY.
DID PUT SOME SHOWERS IN THE FAR WEST LATE MONDAY AND ACROSS THE
AREA ON TUE. MODELS SHOW ANOTHER COLD FRONT MOVING IN.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
LOW CIGS AND FOG WILL SUPPORT REDUCED FLYING CONDS ACROSS THE
ENTIRE AIRSPACE OVER NIGHT..WIDESPREAD MVFR AND IFR OR LOWER
ACROSS HIER ELEVATIONS. CONDS CAUSED BY FRONTAL BOUNDARY VCNTY
STATE AND ABUNDANT LOW LEVEL MOISTURE FROM ONGOING SHOWERS AND
THOSE FROM EARLIER TODAY.
WINDS WILL REMAIN LIGHT INTO WED.
OUTLOOK...
WED...WIDESPREAD MVFR/IFR IN SHRA/PERIODS OF RA.
THU...REDUCTIONS LIKELY IN SCT SHRA.
FRI...REDUCTIONS LIKELY IN SHRA...ESPECIALLY DURING THE
AFT. CHC OF THUNDER AFT.
SAT-SUN...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR/FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR
LONG TERM...LAMBERT/MARTIN
AVIATION...DEVOIR/GARTNER
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
806 PM EDT TUE APR 7 2015
.SYNOPSIS...
MOIST SOUTHWESTERLY FLOW WILL PERSIST OVER THE REGION THROUGH THE
WORK WEEK...KEEPING CONDITIONS UNSETTLED WITH CHANCES FOR SHOWERS
AND THUNDERSTORMS EACH DAY. A COLD FRONT IS THEN EXPECTED TO CROSS
THE CAROLINAS DURING THE FIRST HALF OF THE WEEKEND...WHICH SHOULD
ALLOW FOR DRIER WEATHER TO RETURN.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 745 PM...CLUSTER OF SHOWERS AND TSTMS PERSISTS OVER THE ERN
UPSTATE AND ADJACENT NC BORDER AREAS. THESE SEEM TO BE PROPAGATING
SLOWLY SWD AS THEY MOVE EAST...TOWARD MORE UNSTABLE AIR.
MESOANALYSIS STILL SHOWS A FAIR AMOUNT OF SBCAPE OVER MOST OF THE
CWA NORTH OF THE CURRENT ACTIVITY...AND THERE IS STILL THE SHORTWAVE
PASSAGE EXPECTED LATER THIS EVENING. WON/T RULE OUT SOME
REDEVELOPMENT. THE HRRR HAD BEEN SHOWING STORMS FIRING UP 00-02Z IN
THE NC FOOTHILLS AND MOVING EAST. IT NO LONGER APPEARS TO BE
VERIFYING THAT WELL...BUT SHOWS SOME SCT CELLS RE-FORMING THIS
EVENING. KEPT MOSTLY CHC POPS ACRS THE AREA UNTIL MIDNIGHT OR SO
WHEN THEY TAPER OFF TO SCHC OR LOWER. SUPPORTIVE LLVL PROFILES
SUGGEST SOME DENSE FOG WILL DEVELOP OVERNIGHT WHERE HEAVY RAIN FELL
THIS AFTN...AT LEAST OF A BRIEF OR PATCHY NATURE. ADDED THIS MENTION
TO THE FCST.
AS OF 230 PM TUESDAY...SBCAPE VALUES ARE BEGINNING TO INCREASE
ESPECIALLY ACROSS THE UPSTATE AND WESTERN PORTIONS OF THE PIEDMONT
AND FOOTHILLS AS SUNSHINE BEGINS TO PEEK THROUGH THE RATHER
WIDESPREAD CLOUD COVER. AN AREA OF SHOWERS AND THUNDERSTORMS MOVING
ACROSS THE MOUNTAINS ASSOCIATED WITH A WEAK SHORTWAVE ALOFT WILL
CONTINUE TO PUSH EAST FOR THE NEXT COUPLE OF HOURS. LIGHTNING
ACTIVITY IN THIS AREA OF CONVECTION HAS REALLY DROPPED OFF AS THE
PRECIPITATION CROSSED THE RIDGES. ANOTHER SHORTWAVE BEHIND THIS
INITIAL DISTURBANCE SHOULD PASS MAINLY TO OUR NORTH LATE THIS
EVENING AND EARLY OVERNIGHT...BUT HAS ENOUGH INFLUENCE THAT HIRES
REFLECTIVITY IS STILL DEVELOPING ISOLATED TO SCATTERED CONVECTION
ACROSS THE AREA OFF AND ON THROUGH ABOUT MIDNIGHT. OVERALL SEVERE
THREAT REMAINS MINIMAL...WITH CAPE CHARACTERISTICS GENERALLY TALL
AND SKINNY THIS AFTERNOON AND EVENING AND NOT CONDUCIVE TO MUCH MORE
THAN A FEW GUSTY WINDS AND PERHAPS SOME SMALL HAIL...BUT CONFIDENCE
IS LOW DESPITE THE SPC DAY1 MARGINAL RISK AREA JUST BECAUSE THERE
REALLY IS NOT MUCH CAPE IN THE HAIL GROWTH REGION. CANNOT RULE OUT
SOMETHING ISOLATED OF COURSE.
SHOULD SEE A LULL IN PRECIPITATION OVERNIGHT AS DEEPENING SYSTEM OUT
WEST INCREASES THE AMPLITUDE OF THE WAVETRAIN...INDUCING DOWNSTREAM
RIDGING TO STRENGTHEN OVER THE SOUTHEAST AND MID-ATLANTIC. DEPENDING
ON EXTENT OF EVENING/EARLY OVERNIGHT CONVECTION...COULD SEE MORE LOW
CLOUDS IN THE MORNING BUT OVERALL PATTERN REMAINS WELL ABOVE NORMAL
FOR OVERNIGHT LOWS...SOME AREAS MAYBE 15 DEGREES ABOVE NORMAL.
ANOTHER WEAK SHORTWAVE PUSHES THROUGH THE FLOW ALOFT MIDDAY
WEDNESDAY... AGAIN REMAINING GENERALLY FARTHER TO THE NORTH...BUT
ENOUGH TO CONTINUE THE NEARLY DIURNAL TREND IN CONVECTION CHANCES
THROUGH THE END OF THE NEAR TERM. HOWEVER...DUE TO THE RIDGING
ALOFT...BUFR SOUNDINGS ACROSS THE FORECAST AREA REMAIN CAPPED AND
WITHOUT ANY MECHANICAL LIFTING TO SPEAK OF WOULD NEED TO REACH
CONVECTIVE TEMPERATURES. NO SHEAR TO SPEAK OF TO ASSIST IN
ORGANIZING ANY POTENTIAL CONVECTION. HIGHS TOMORROW WILL DEFINITELY
BE ON THE WARM /AND WELL ABOVE SEASONAL NORMALS/ SIDE...WITH LOW TO
MID 80S ACROSS THE PIEDMONT AND FOOTHILLS AND EVEN UPPER 70S IN SOME
OF THE MOUNTAIN VALLEYS. OVERALL THOUGH PRECIPITATION AND CONVECTION
CHANCES TOMORROW LOOK LOWER THAN THOSE THIS AFTERNOON.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 230 PM TUESDAY...NOT MUCH HAS CHANGED WITH THE THINKING FOR
HOW THE SHORT RANGE MAY PLAY OUT. THE SLOWLY PROGRESSIVE AND
AMPLIFYING UPPER PATTERN WILL KEEP THE WRN CAROLINAS AND NE GEORGIA
IN A BROAD WARM SECTOR ON THURSDAY THAT WILL ENSURE SUFFICIENT LOW
LEVEL MOISTURE TO FUEL SHOWERS AND THUNDERSTORMS. ANY REMAINING
STORMS ON WEDNESDAY EVENING SHOULD SLOWLY DIMINISH WITH LOSS OF
HEATING...MAINLY OVER THE PIEDMONT. THINK WE SHOULD SEE A LULL IN
ACTIVITY ON THURSDAY MORNING AROUND DAYBREAK...SO THE PRECIP
PROBABILITY WAS TAKEN DOWN BELOW 15 PERCENT THEN. WITH SOME DAYTIME
HEATING...EXPECT DEEP CONVECTION TO FIRE ONCE AGAIN ON THURSDAY OVER
THE MTNS BY MIDDAY AND THEN SPREAD EASTWARD FROM THERE. A COUPLE OF
ISSUES COULD POTENTIALLY HAVE A BIG IMPACT. THERE REMAINS SOME
CONCERN ABOUT THE PRESENCE AND/OR LOCATION OF A BACK DOOR COLD FRONT
IN THE AFTERNOON. THE OPERATIONAL MODELS HINT THAT THE BOUNDARY MAY
MAKE IT DOWN TO THE NW PIEDMONT AND NO FARTHER...SO UNLESS THAT
DEPICTION IS WRONG...WE WILL NOT HAVE THAT TRIGGER OR FOCUS.
INSTEAD...WE MAY HAVE TO RELY ON DIFFERENTIAL HEATING OVER THE MTNS
AND THE PASSAGE OF ANOTHER WEAK SHORT WAVE LATE IN THE DAY. THE
MODELS SUGGEST THAT BUOYANCY WILL NOT BE AS GREAT AND LAPSE RATES
MAY NOT BE QUITE AS STEEP...BUT IT MAKES UP FOR THAT WITH INCREASED
SHEAR. THE MODELS ARE IN GENERAL AGREEMENT THAT SRH MAY APPROACH 150
M2/S2 AND SHEAR AROUND 30 KT. THAT COULD PROVIDE FOR SOME
OPPORTUNITY FOR STORM ORGANIZATION. WE WILL HAVE TO KEEP AN EYE ON
THIS POSSIBLE DEVELOPMENT.
THE MAIN FOCUS CONTINUES TO BE ON THE FRONTAL PASSAGE ON FRIDAY.
PRECIP CHANCES RAMP UP FROM THE WEST EARLY FRIDAY AND CONTINUE
UPWARD AND EASTWARD FROM THERE. THE COMBINATION OF AN UNSTABLE PRE-
FRONTAL AIR MASS AND INCREASING UPPER FORCING SUPPORT PRECIP
PROBABILITIES IN THE LIKELY RANGE BY THE AFTERNOON. THE MODELS ARE
IN GENERAL AGREEMENT WITH BRINGING THE BOUNDARY INTO THE MTNS BY THE
END OF THE DAYTIME PERIOD BUT HOLDING IT UP BRIEFLY FRIDAY EVENING.
THE AMOUNT AND COVERAGE OF SEVERE THUNDERSTORMS IS THE MAIN
CONCERN...AS NEARLY THE ENTIRE FCST AREA IS IN THE DAY 4 PART OF THE
SVR WX OUTLOOK. THIS IS BY NO MEANS CERTAIN. THE MODEL GUIDANCE
CONTINUES TO SHOW AN AIR MASS CONTAMINATED BY CONVECTIVE DEBRIS THAT
CUTS DOWN SIGNIFICANTLY ON BUOYANCY...BUT STILL HAS DECENT SHEAR.
BETTER INSTABILITY WILL BE ACROSS THE COASTAL PLAIN. CONFIDENCE IS
NOT HIGH ENOUGH TO MENTION THE SEVERE THREAT FOR FRIDAY IN THE HWO
UPDATE. THE FRONT SHOULD MOVE THRU LATE FRIDAY EVE/EARLY SATURDAY
MORNING...ENDING THE THUNDERSTORM THREAT. HAVE RETAINED A SMALL
CHANCE OVER THE EASTERN FRINGE AT 12Z SATURDAY IN DEFERENCE TO THE
OLD ECMWF...BUT HAVE A HUNCH THAT PRECIP WILL BE LONG GONE BY THEN.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 2 PM TUESDAY...THE MEDIUM RANGE FCST PICKS UP AT 12Z ON
SATURDAY WITH RELATIVELY FLAT UPPER RIDGING OVER THE CAROLINAS AND
AN UPPER TROF MOVING EAST OF THE GREAT LAKES AND REMAINING WELL TO
OUR NORTH. OVER THE REMAINDER OF THE WEEKEND...HEIGHTS GRADUALLY
RISE AS SMALL AMOUNTS OF SHORTWAVE ENERGY RIPPLE OVER THE AREA. AS
WE MOVE INTO EARLY NEXT WEEK...THE LONG RANGE MODELS SUGGEST THAT
THE PATTERN WILL AMPLIFY WITH A DEEP UPPER TROF APPROACHING THE CWFA
BY THE END OF THE PERIOD. AT THE SFC...CANADIAN HIGH PRESSURE WILL
BE SPREADING ACROSS THE FCST AREA AS THE PERIOD BEGINS. IT IS
EXPECTED TO LINGER THRU MOST OF THE WEEKEND AND SLIDE EAST AND
OFFSHORE EARLY NEXT WEEK. AS IT DOES...ANOTHER GREAT PLAINS LOW
DEVELOPS TO OUR WEST AND MAKES ITS WAY TOWARDS THE GREAT LAKES.
SIMULTANEOUSLY...MOIST SOUTHERLY LOW LVL FLOW SETS UP ACROSS THE
FCST AREA AGAIN AND LINGERS INTO NEW DAY 7. THIS TRANSLATES TO
MOSTLY DRY CONDITIONS ON SAT AND SUN AND INCREASING POPS FOR MON AND
TUES.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...THREAT OF CONVECTION HAS ALREADY PEAKED FOR THE
EVENING...BUT ANALYSES SHOW SOME LINGERING ELEVATED INSTABILITY
WHICH MIGHT BE ACTED UPON BY A PASSING SHORTWAVE. A TS IS NOT OUT OF
THE QUESTION BUT MORE LIKELY JUST SHOWERS WILL AFFECT THE FIELD...SO
TEMPO IS USED. MAINLY MIDLEVEL CIGS WILL BE SEEN OVERNIGHT AS
ELEVATED MOISTURE AND FORCING WANE. THE SFC WILL REMAIN FAIRLY MOIST
HOWEVER...AND SOME LIGHT FOG IS MORE LIKELY THAN NOT. DIURNAL
DESTABILIZATION WILL OCCUR AFTER DAYBREAK ALLOWING FOR CU TO FORM AT
LOW VFR. CHANCE OF TSRA RETURNS IN THE AFTN...HENCE PROB30. WINDS
WILL BE VARIABLE WITH PRECIP IN THE AREA THIS EVENING...BUT
OTHERWISE WILL PREVAIL MAINLY SOUTHERLY THRU THE PERIOD.
ELSEWHERE...CHANCE OF TSRA AT THE SITES IS RATHER LOW THIS EVENING
BUT UNTIL THE INCOMING SHORTWAVE DEPARTS A STRAY SHOWER OR TS IS NOT
OUT OF THE QUESTION. KGSP/KGMU SAW TS JUST BEFORE 00Z AND MAY SEE
SOME LINGERING EFFECTS FOR AN HR OR TWO TO START THE TAF.
KAVL...KGSP AND KGMU ALL TOOK DIRECT HITS FROM STORMS WHICH GAVE
THEM A GOOD SOAKING. KHKY GOT SOME LIGHT RAIN. THOUGH MIDLEVEL CIGS
WILL BE PRESENT...PROFILES LATER TONIGHT AT ALL 4 OF THESE SITES
WOULD SUPPORT SOME FOG THREAT GIVEN MOIST DEWPOINTS AND WET SOILS.
RESTRICTIONS OVERNIGHT ARE UNLIKELY EXCEPT FOR WHAT FOG OR LOW
STRATUS DEVELOP OVER AREAS THAT SAW APPRECIABLE RAINFALL THIS AFTN.
WINDS WILL FAVOR SOUTHERLY WHERE NOT AFFECTED BY SHRA/TSRA THIS
EVENING.
OUTLOOK...PATTERN OF UNSETTLED WEATHER WILL CONTINUE THROUGH THE
WEEK...UNTIL A COLD FRONT PUSHES THROUGH LATE FRIDAY. EXPECT AT
LEAST SCATTERED AFTERNOON CONVECTION EACH DAY WITH POTENTIAL FOR
RESTRICTIONS EACH MORNING. MUCH IMPROVED CONDITIONS FOR THE WEEKEND
AFTER THE FRONT CLEARS THE AREA.
CONFIDENCE TABLE...
00-06Z 06-12Z 12-18Z 18-00Z
KCLT HIGH 97% HIGH 88% HIGH 94% HIGH 100%
KGSP HIGH 100% HIGH 86% HIGH 100% HIGH 100%
KAVL HIGH 80% HIGH 86% MED 73% HIGH 100%
KHKY HIGH 96% HIGH 91% HIGH 89% HIGH 100%
KGMU HIGH 100% HIGH 94% HIGH 97% HIGH 100%
KAND HIGH 100% HIGH 80% MED 76% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...TDP/WIMBERLEY
SHORT TERM...PM
LONG TERM...JPT
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
841 PM CDT TUE APR 7 2015
.UPDATE...
SEE EVENING UPDATE.
&&
.DISCUSSION...
00Z SOUNDINGS SHOW A CAPPING LAYER BETWEEN 850-700 MB AND
RELATIVELY MEAGER PW VALUES. 850 MB MSTR IS CONFINED TO NE TX TO
SE LA. 700MB LOOKS VERY DRY WITH VERY WARM 700 MB TEMPS EXTENDING
FROM LCH TO BRO. TWEAKED SKY GRIDS AS LOW LEVEL CLOUDS EXPANDING
QUICKLY OVER THE COASTAL COUNTIES. LEANED TOWARD THE HRRR FOR
CLOUD COVER TONIGHT AND FEEL SKIES WILL BECOME MOSTLY CLOUDY PRIOR
TO SUNRISE. MIN TEMPS LOOK ON TRACK SO NO CHANGES PLANNED THERE.
PATCHY FOG STILL BEING REPORTED OVER THE WESTERN GULF SO WILL KEEP
WX GRIDS AS IS.
LOOKING AHEAD...CURRENT FCST SEEMS TO HAVE A GOOD HANDLE ON TWO
WEATHER EVENTS FOR LATER THIS WEEK AND OVER THE WEEKEND. LOOKS
LIKE HIGH RAIN CHANCES FRI-SUN WITH SUNDAY LOOKING INTERESTING FOR
BOTH HEAVY RAIN AND POSSIBLY STRONG STORMS.
THE HIGH AT BUSH IAH TODAY WAS 87 DEGREES. IT IS THE WARMEST
TEMPERATURE SO FAR THIS YEAR. THE LAST TIME HOUSTON REACHED 87
DEGREES WAS ON OCT 16 2014. 43
&&
.PREV DISCUSSION... /ISSUED 627 PM CDT TUE APR 7 2015/
DISCUSSION...
SEE THE 00Z AVIATION DISCUSSION BELOW.
40
AVIATION...
THE MODEL FORECAST SOUNDINGS CONTINUE THE THEME OF THE 12Z RAOB
SOUNDINGS AND KEEP A LOW-LEVEL CAPPING INVERSION IN PLACE TONIGHT
INTO WEDNESDAY. EXPECTING MVFR CEILINGS TO DEVELOP BY AROUND 06Z
AND PERSIST THROUGH POSSIBLY AS LATE AS 16Z. SOME LOCATIONS MAY
EXPERIENCE BRIEF IFR CONDITIONS...ALTHOUGH THESE LOOK TO BECOME
MORE PREVALENT AT KLBX AND KGLS. EXPECTING VFR AND BREEZY
CONDITIONS TO DEVELOP DURING THE LATE MORNING WEDNESDAY.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 69 84 70 83 68 / 10 10 20 50 40
HOUSTON (IAH) 69 83 71 83 70 / 10 10 10 30 30
GALVESTON (GLS) 70 79 71 80 71 / 10 10 10 20 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
703 PM CDT TUE APR 7 2015
.AVIATION... /00Z TAF UPDATE/
CONVECTION OVER MEXICO IS NOT ACCOUNTED FOR IN THE DRT IN THIS TAF
UPDATE AS MOST OF THE MODEL DATA SHOWS LITTLE OR NO ACTIVITY
LATER THIS EVENING. AN OUTLIER IS THE HRRR WHICH SHOWS A SMALL
COMPLEX DEVELOP AND POSSIBLY IMPACT AREAS ALONG THE RIO GRANDE
LATE TONIGHT. MODEL GUIDANCE SUGGESTS MVFR CIGS WILL ARRIVE BY
MIDNIGHT AGAIN AND LOWERS BOTH CIGS AND VSBYS INTO IFR CATEGORIES
EARLY WEDNESDAY. WILL LEAN ON PERSISTENCE TO KEEP VSBYS A BIT
HIGHER. AS WITH TODAY...MUCH OF THE DAY WEDNESDAY SKIES SHOULD BE
FILLED WITH AN MVFR CIG. WINDS SHOULD ALSO FOLLOW A DIURNAL
PERSISTENCE TREND.
&&
.PREV DISCUSSION... /ISSUED 310 PM CDT TUE APR 7 2015/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...STRATOCU HAS
BEEN SLOWER TO ERODE ALONG THE RIO GRANDE THAN EXPECTED THIS
AFTERNOON...BUT SHOULD EVENTUALLY SCATTER OUT THROUGH THE LATE
AFTERNOON HOURS. ISOLATED CONVECTION BEGINNING TO DEVELOP ALONG
THE HIGHER TERRAIN IN MEXICO. CAN NOT RULE AN ISOLATED STORM
CROSSING INTO VAL VERDE COUNTY EARLY THIS EVENING...BUT CAP MAY
HOLD...ESPECIALLY GIVEN AFOREMENTIONED CLOUDS THAT WERE SLOW TO
ERODE. STRATUS RE-DEVELOPS OVERNIGHT AND SCATTERS TOMORROW
AFTERNOON SIMILAR TO TODAY. OTHERWISE WARM AND BREEZY TOMORROW.
THE DRY LINE ADVANCES SLIGHTLY FARTHER EAST THURSDAY AFTERNOON...
AND WITH WEAK MID LEVEL DISTURBANCE THE CAP DOES ERODE LATE
AFTERNOON ACROSS THE FAR WESTERN AREAS. COULD SEE ISOLATED STORMS
DEVELOPING OVER THE FAR NORTHERN HILL COUNTRY AND EDWARDS PLATEAU
TOMORROW AFTERNOON ADVANCING SOUTHEAST INTO THE SOUTHERN HILL
COUNTRY TOMORROW EVENING. AT THE MOMENT UNSURE IF STORMS WILL HOLD
TOGETHER INTO THE I-35 CORRIDOR LATE EVENING GIVEN THE CAP. CAN
NOT RULE OUT THE POSSIBILITY OF A STRONG STORM OR TWO TOMORROW
AFTERNOON AND EVENING...ESPECIALLY CLOSER TO THE RIO GRANDE.
LONG TERM (THURSDAY THROUGH TUESDAY)...THE DRY LINE ADVANCES ALL
THE WAY INTO VAL VERDE COUNTY ON THURSDAY AFTERNOON....WITH THE
MOIST LOW LEVEL THETA-E RIDGE ALONG AND EAST OF I-35. ANOTHER MID
LEVEL SHORTWAVE AND COOLING HELPS TO ERODE CAP FARTHER INTO THE
CENTRAL AND EASTERN CWA. THE BETTER CHANCES FOR CONVECTION
THURSDAY WILL BE ALONG AND NORTH OF A FREDERICKSBURG TO SAN MARCOS
TO LA GRANGE LINE. A FEW STRONGER STORMS WILL BE POSSIBLE ALONG
AND NORTH OF THIS LINE.
A WEAK COLD FRONT ENTERS THE AREA EARLY FRIDAY MORNING...STALLING
ALONG OR NORTH OF I-10...THEN LIFTING BACK TO THE NORTH FRIDAY
AFTERNOON AND EVENING. MOISTURE POOLING WILL BE BEST ACROSS THE
WESTERN CWA...COINCIDING WITH BROAD LOW LEVEL CONVERGENCE AXIS.
SCATTERED POPS ARE FORECAST FOR THE ENTIRE...BUT BEST CHANCES WILL
BE OUT WEST. BOTH THE ECMWF AND GFS SHOW 700MB SHORTWAVE AND
MOISTURE POOL MOVING NORTHEAST THROUGH THE EDWARDS PLATEAU AND
NORTHERN HILL COUNTRY ON FRIDAY. FORECAST SOUNDINGS INDICANT DEEP
LAYER SHEAR AND INSTABILITY WILL BE SUFFICIENT FOR A FEW STRONG TO
SEVERE STORMS FRIDAY ALONG THE RIO GRANDE...EDWARDS PLATEAU AND
HILL COUNTRY.
DO MAINTAIN POPS INTO SATURDAY GIVEN THE MOISTURE POOL OVER THE
AREA...BUT LACK OF SIGNIFICANT FORCING FEATURE MAY KEEP COVERAGE
IN THE LOW END SCATTERED RANGE. BETTER SHOT FOR SHOWERS AND STORMS
COMES INTO THE FORECAST SUNDAY AND SUNDAY NIGHT...AS SOUTHERN
STREAM UPPER LEVEL SHORTWAVE ACROSS BAJA CALIFORNIA EJECTS EAST
ACROSS TEXAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 68 83 68 84 66 / - 10 20 40 30
AUSTIN BERGSTROM INTL AIRPORT 68 84 68 82 66 / - 10 20 30 30
NEW BRAUNFELS MUNI AIRPORT 68 86 67 85 66 / - 10 20 20 20
BURNET MUNI AIRPORT 67 82 66 84 64 / - 10 20 40 30
DEL RIO INTL AIRPORT 68 86 67 89 68 / 10 20 20 - 20
GEORGETOWN MUNI AIRPORT 68 83 67 83 65 / - 10 20 40 40
HONDO MUNI AIRPORT 68 86 67 86 67 / - 10 20 20 10
SAN MARCOS MUNI AIRPORT 69 82 68 84 66 / - 10 20 30 20
LA GRANGE - FAYETTE REGIONAL 70 84 70 83 69 / - 10 10 30 20
SAN ANTONIO INTL AIRPORT 69 86 69 85 67 / - 10 20 20 20
STINSON MUNI AIRPORT 69 87 68 85 68 / - 10 10 20 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...18
SYNOPTIC/GRIDS...05
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
604 PM CDT MON APR 6 2015
.AVIATION...
VFR IS CURRENTLY PREVAILING AT ALL SITES AT THE PRESENT HOUR.
HOWEVER...DETERIORATING CONDITIONS CAN BE EXPECTED ONCE AGAIN
AFTER SUNSET WITH MVFR RETURNING BY 04-05Z. CEILINGS WILL LOWER
EVEN FURTHER TO IFR BY 9Z. LIFR IS ALSO POSSIBLE BUT WILL KEEP
THINGS IFR FOR NOW. CONDITIONS WILL IMPROVE BACK TO MVFR AROUND
17Z...THEN VFR A COUPLE OF HOURS LATER. CONVECTION WEST OF THE RIO
GRANDE IS NOT EXPECTED TO IMPACT KDRT DUE TO A STRONG CAPPING
INVERSION.
HAMPSHIRE
&&
.PREV DISCUSSION... /ISSUED 321 PM CDT MON APR 6 2015/
SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...
THE AFTERNOON VISIBLE SATELLITE IMAGERY STILL SHOWS PLENTY OF CLOUD
COVER IN PLACE ACROSS SOUTH CENTRAL TEXAS. THIS WILL LIMIT THE
OVERALL INSTABILITY AND LIKELY ALLOW THE MID-LEVEL CAPPING
INVERSION TO KEEP CONVECTION FROM DEVELOPING ACROSS MOST AREAS
THROUGH EARLY THIS EVENING. THE ONE EXCEPTION WILL BE OUT WEST
ACROSS THE SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS. SPC
MESOANALYSIS SHOWS A NARROW AXIS OF SURFACE-BASED CAPE ALONG WITH
A LOCALIZED MIN IN CONVECTIVE INHIBITION. THE HRRR CONTINUES TO
SUGGEST THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS TO DEVELOP
NEAR THE SERRANIAS DEL BURRO MOUNTAINS...THEN MOVE EAST INTO THE
RIO GRANDE PLAINS. IF CONVECTION DOES MANAGE TO DEVELOP...A STRONG
STORM OR TWO REMAINS POSSIBLE WITH HAIL AND GUSTY WINDS BEING THE
MAIN THREATS. WARM AND DRY CONDITIONS ARE EXPECTED ON TUESDAY AS
SOUTHWESTERLY FLOW ALOFT REMAINS INTACT.
LONG TERM (WEDNESDAY THROUGH MONDAY)...
ON WEDNESDAY...SOUTHWEST FLOW ALOFT WILL CONTINUE ACROSS THE REGION. AN
INCREASE IN MID-LEVEL SHORTWAVE ACTIVITY COULD LEAD TO AN UPTICK IN
PRECIPITATION CHANCES ACROSS MOST AREAS LATE WEDNESDAY INTO EARLY
THURSDAY. A FEW STRONG TO SEVERE STORMS REMAIN POSSIBLE ACROSS THE
SOUTHERN EDWARDS PLATEAU AND NORTHWEST HILL COUNTRY DURING THE LATE
AFTERNOON AND EVENING HOURS. FOR THE REMAINDER OF THE WORK WEEK AND
UPCOMING WEEKEND...SOUTHWEST FLOW ALOFT CONTINUES AND BECOMES
INCREASINGLY ACTIVE. WE/LL CONTINUE TO MENTION A LOW CHANCE FOR SHOWERS
AND THUNDERSTORMS ACROSS MOST AREAS. THE MEDIUM RANGE MODELS SHOW A
STRONGER UPPER LEVEL TROUGH MOVING IN FROM THE WEST THIS WEEKEND.
THERE ARE SOME TIMING DIFFERENCES AND WILL AWAIT ADDITIONAL MODEL
RUNS BEFORE ADJUSTING THE CURRENT FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 69 84 69 84 68 / 10 10 10 10 10
AUSTIN BERGSTROM INTL AIRPORT 68 83 68 83 68 / 10 10 10 10 10
NEW BRAUNFELS MUNI AIRPORT 67 85 67 85 68 / 10 10 10 10 10
BURNET MUNI AIRPORT 67 84 66 83 66 / 10 10 10 10 20
DEL RIO INTL AIRPORT 69 87 69 88 68 / 20 10 10 10 30
GEORGETOWN MUNI AIRPORT 68 83 68 83 68 / 10 10 10 10 20
HONDO MUNI AIRPORT 68 84 68 86 68 / 10 10 - 10 10
SAN MARCOS MUNI AIRPORT 68 84 68 83 68 / 10 10 10 10 10
LA GRANGE - FAYETTE REGIONAL 69 84 70 83 71 / 10 10 10 10 10
SAN ANTONIO INTL AIRPORT 68 84 69 84 69 / 10 10 10 10 10
STINSON MUNI AIRPORT 68 84 68 85 69 / 10 10 10 10 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...29
SYNOPTIC/GRIDS...17
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
321 PM CDT MON APR 6 2015
.SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...
THE AFTERNOON VISIBLE SATELLITE IMAGERY STILL SHOWS PLENTY OF CLOUD
COVER IN PLACE ACROSS SOUTH CENTRAL TEXAS. THIS WILL LIMIT THE
OVERALL INSTABILITY AND LIKELY ALLOW THE MID-LEVEL CAPPING
INVERSION TO KEEP CONVECTION FROM DEVELOPING ACROSS MOST AREAS
THROUGH EARLY THIS EVENING. THE ONE EXCEPTION WILL BE OUT WEST
ACROSS THE SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS. SPC
MESOANALYSIS SHOWS A NARROW AXIS OF SURFACE-BASED CAPE ALONG WITH
A LOCALIZED MIN IN CONVECTIVE INHIBITION. THE HRRR CONTINUES TO
SUGGEST THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS TO DEVELOP
NEAR THE SERRANIAS DEL BURRO MOUNTAINS...THEN MOVE EAST INTO THE
RIO GRANDE PLAINS. IF CONVECTION DOES MANAGE TO DEVELOP...A STRONG
STORM OR TWO REMAINS POSSIBLE WITH HAIL AND GUSTY WINDS BEING THE
MAIN THREATS. WARM AND DRY CONDITIONS ARE EXPECTED ON TUESDAY AS
SOUTHWESTERLY FLOW ALOFT REMAINS INTACT.
&&
.LONG TERM (WEDNESDAY THROUGH MONDAY)...
ON WEDNESDAY...SOUTHWEST FLOW ALOFT WILL CONTINUE ACROSS THE REGION. AN
INCREASE IN MID-LEVEL SHORTWAVE ACTIVITY COULD LEAD TO AN UPTICK IN
PRECIPITATION CHANCES ACROSS MOST AREAS LATE WEDNESDAY INTO EARLY
THURSDAY. A FEW STRONG TO SEVERE STORMS REMAIN POSSIBLE ACROSS THE
SOUTHERN EDWARDS PLATEAU AND NORTHWEST HILL COUNTRY DURING THE LATE
AFTERNOON AND EVENING HOURS. FOR THE REMAINDER OF THE WORK WEEK AND
UPCOMING WEEKEND...SOUTHWEST FLOW ALOFT CONTINUES AND BECOMES
INCREASINGLY ACTIVE. WE/LL CONTINUE TO MENTION A LOW CHANCE FOR SHOWERS
AND THUNDERSTORMS ACROSS MOST AREAS. THE MEDIUM RANGE MODELS SHOW A
STRONGER UPPER LEVEL TROUGH MOVING IN FROM THE WEST THIS WEEKEND.
THERE ARE SOME TIMING DIFFERENCES AND WILL AWAIT ADDITIONAL MODEL
RUNS BEFORE ADJUSTING THE CURRENT FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 69 84 69 84 68 / 10 10 10 10 10
AUSTIN BERGSTROM INTL AIRPORT 68 83 68 83 68 / 10 10 10 10 10
NEW BRAUNFELS MUNI AIRPORT 67 85 67 85 68 / 10 10 10 10 10
BURNET MUNI AIRPORT 67 84 66 83 66 / 10 10 10 10 20
DEL RIO INTL AIRPORT 69 87 69 88 68 / 20 10 10 10 30
GEORGETOWN MUNI AIRPORT 68 83 68 83 68 / 10 10 10 10 20
HONDO MUNI AIRPORT 68 84 68 86 68 / 10 10 - 10 10
SAN MARCOS MUNI AIRPORT 68 84 68 83 68 / 10 10 10 10 10
LA GRANGE - FAYETTE REGIONAL 69 84 70 83 71 / 10 10 10 10 10
SAN ANTONIO INTL AIRPORT 68 84 69 84 69 / 10 10 10 10 10
STINSON MUNI AIRPORT 68 84 68 85 69 / 10 10 10 10 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...15
SYNOPTIC/GRIDS...24
PUBLIC SERVICE/DATA COLLECTION...12
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1141 PM CDT Sun Apr 5 2015
.AVIATION...
/06Z TAFS/
Stratus with IFR ceilings was just east of KABI and KBBD, with
MVFR stratus in the Hill Country south of KJCT. Expect stratus to
develop westward into terminal overnight. IFR ceiling should rise
to MVFR/VFR by 18Z. Thunderstorms west the Pecos River may affect
KSOA after 7Z and KJCT and KBBD after 8Z according to the short
range HRRR model, so have VCTS in those terminals through 12Z.
&&
.PREV DISCUSSION... /ISSUED 651 PM CDT Sun Apr 5 2015/
AVIATION...
/00Z TAFS/
Stratus along an Abilene to Brady to east of Junction line this
afternoon will move back west this evening. Ceilings initially will
start off as MVFR but fall to IFR overnight. IFR/MVFR stratus will
lift to MVFR/VFR early Monday afternoon.
PREV DISCUSSION... /ISSUED 326 PM CDT Sun Apr 5 2015/
SHORT TERM...
(Tonight and Tomorrow)
Main concern with this package is with the threat for a few
thunderstorms across Crockett County tonight and areas to the
east.
A couple of storms have formed in the Davis Mountains and they are
moving east. The models did show a jet max moving across West Texas
tonight, placing WC TX in the favored right rear entrance region.
This upper level jet max combined with the increasing low level jet
could sustain convection tonight. Although the latest HRRR run
progged a large area of convection moving into the southern half of
WC TX overnight, still have low confidence since all of the other
models showed nothing. Will continue slight chance Pops for
thunderstorms mainly across Crockett County tonight. If this
convection persists, the Pops may have to be adjusted east and
northeast.
Expect the low clouds across the east to slowly erode through the
early evening. With plenty of low level gulf moisture across the
region, expect low clouds to develop overnight.
As the low clouds burn off tomorrow afternoon, temperatures will
quickly warm mostly into the mid and upper 80s. The models show the
dryline setting up west of Crockett County across the Trans Pecos
region. Model soundings show a strong cap through 6 PM tomorrow and
this should keep any convection from forming.
26
LONG TERM...
(Tomorrow night through Sunday)
The main concern through the extended forecast is the potential for
showers and thunderstorms Wednesday, and toward the latter part of
the week for much of West Central Texas. Monday afternoon/evening
the dryline will set up across our western border. Showers and
thunderstorms may develop during the evening hours, mainly across
the Trans Pecos region of West Texas. A few of these storms may
drift into mainly Crockett County during the evening hours, where
slight chance PoPs are included. On Tuesday, the dryline will once
again move east to about our western boundary, during the late
afternoon/early evening. At this time, the cap looks to dominate,
with little to no convection developing. An isolated thunderstorms
will be possible if we are able to break the cap, but the forecast
was kept dry for now.
Models are in fairly good agreement showing the next upper level
low/trough centered across Utah/Colorado on Wednesday, then tracking
across the Central Plains Thursday. Ahead of this feature, a dryline
is forecast to move east to near our western border late Wednesday
afternoon/evening. Enough afternoon heating (highs in the mid 80s to
low 90s) and lift from the upper level trough should allow for the
development of isolated to scattered showers and thunderstorms,
mainly during the late afternoon/evening, then moving across the
area overnight. The ECMWF continues to be much drier than both the
GFS/Canadian, but geared the forecast closer to the wetter GFS. A
fairly unstable atmosphere will lie along and ahead of the dryline,
with SBCAPE values generally in the 1500-2500 J/KG range and 0-6 KM
shear values in the 35 to 50 knot range. Strong to severe
thunderstorms will be possible, with large hail and damaging winds
being the main hazards at this time.
With the passage of the upper level trough, a cold front will move
through West Central Texas on Thursday. Slightly cooler temperatures
are forecast Thursday into the weekend, with highs generally in the
mid 70s to low 80s. The next upper level low across the Pacific
Ocean will then begin to approach California, with West Central
Texas in southwest flow aloft. Intermittent disturbances may result
in isolated to scattered showers and thunderstorms, Friday into next
weekend, and this is reflected in the grids. The aforementioned
upper level low will eventually tack across West Texas or New
Mexico, which may bring an increasing chance of showers and
thunderstorms for late in the weekend or early next week.
Daniels
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 65 88 66 89 66 / 10 10 10 10 10
San Angelo 64 87 66 89 66 / 10 5 10 10 10
Junction 66 83 68 84 66 / 10 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
04
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1139 PM CDT SUN APR 5 2015
.DISCUSSION...
SEE 06Z AVIATION DISCUSSION.
&&
.AVIATION...
A WARM FRONT IS DRAPED ACROSS SE TX. LIFR CIGS/VSBY PREVAIL TO THE
NORTH OF THE FRONT AND IFR/MVFR CONDS PREVAIL TO THE SOUTH. THE
DILEMMA IS DECIDING HOW FAR NORTH THE FRONT WILL MOVE TONIGHT AND
THE CORRESPONDING CEILING HEIGHTS. FEEL THE RAP INITIALIZED BEST
AND LEANED TOWARD A RAP/HRRR/GFS BLEND. DRIER AIR ALOFT SHOULD
BEGIN TO MIX DOWN AROUND 15Z AND MVFR CONDS ARE EXPECTED TO
DEVELOP BETWEEN 15-17Z. MVFR/VFR CONDS EXPECTED DURING THE AFTN
WITH MVFR CONDS AGAIN EXPECTED AFTER 02Z MON NITE. MODERATE SE
WINDS ARE EXPECTED FOR THE NEXT 24 HOURS. 43
&&
.PREV DISCUSSION... /ISSUED 1001 PM CDT SUN APR 5 2015/
UPDATE...
TRICKY OVERNIGHT FORECAST IN TERMS OF TEMPERATURES WITH A WARM
FRONT STALLED ACROSS THE AREA. SUBJECTIVE SURFACE ANALYSIS AT 9 PM
CDT SHOWED THE FRONT DRAPED ROUGHLY ALONG A COLUMBUS TO ELLINGTON
FIELD TO SOUTH OF BEAUMONT LINE...WITH TEMPERATURES IN THE UPPER
50S TO MID 60S NORTH OF IT AND NEAR 70 TO THE SOUTH. THE FRONT IS
ANTICIPATED TO LIFT SLOWLY OVERNIGHT AND NOT MUCH CHANGE IN
TEMPERATURES IS EXPECTED FOR AREAS SOUTH OF THE FRONT
TONIGHT...WITH AREAS NORTH OF IT SEEING SOME ADDITIONAL COOLING
BEFORE WARM AIR ADVECTION BEHIND THE FRONT PROMOTES AN INCREASE IN
TEMPERATURES. LATEST GUIDANCE INDICATES SOME LIGHT RAIN/DRIZZLE
MAY ALSO BE POSSIBLE OVER THE FAR NORTHERN/NORTHEASTERN ZONES AS
A WEAK DISTURBANCE MOVES ACROSS THE AREA FROM NORTHERN MEXICO AND
TWEAKED POPS SLIGHTLY TO ACCOUNT FOR LOW END CHANCES.
PATCHY FOG IS EXPECTED TO PERSIST OVERNIGHT AND HAVE ADDED
MENTION OF PATCHY FOG ACROSS SOUTHEAST TEXAS AS WELL AS THE BAYS
AND NEARSHORE WATERS THROUGH MID-MORNING ON MONDAY. NEARSHORE
WATER TEMPERATURES ARE ESTIMATED TO BE AROUND 70 DEGREES...AND
WITH SOMEWHAT WARMER AND MOISTER AIR ADVECTING OVER THE MARINE
AREAS TONIGHT SOME PATCHY SEA FOG WILL ALSO BE POSSIBLE.
HUFFMAN
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 71 59 81 68 83 / 40 20 10 10 10
HOUSTON (IAH) 73 59 82 68 83 / 40 10 10 10 10
GALVESTON (GLS) 73 69 78 71 80 / 20 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...14
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
900 PM EDT TUE APR 7 2015
.SYNOPSIS...
A WEAK FRONT JUST NORTH OF THE REGION WILL SLIP BACK SOUTH TO
ALONG THE BLUE RIDGE LATE TONIGHT INTO WEDNESDAY. THE BOUNDARY
WILL THEN LIFT BACK TO THE NORTH THURSDAY AHEAD OF A STRONG COLD
FRONT APPROACHING FROM THE WEST. THIS FRONT WILL FINALLY PUSH
THROUGH FROM THE WEST FRIDAY FOLLOWED BY HIGH PRESSURE FOR THE
WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 840 PM EDT TUESDAY...
UPDATE MAINLY TO INCREASE POPS AND THUNDER CHANCES ACROSS THE FAR
WEST BY MIDNIGHT PER WEAKENING UPSTREAM MCS FEATURE THAT SHOULD
REACH THE WESTERNMOST CWA OVER THE NEXT FEW HOURS. HOWEVER GIVEN
LIMITED INSTABILITY PER LATEST SPC ANALYSIS ONLY EXPECTING A
PERIOD OF POSSIBLE HEAVY RAIN BEFORE WHATS LEFT OF THE IMPULSE
HEADS EAST DURING THE EARLY MORNING HOURS. THEREFORE ALSO BUMPED
UP POPS FOR A PERIOD OF LIKELYS OUT TO AND JUST EAST OF THE BLUE
RIDGE PENDING LATER TRENDS OFF THE RATHER WET HRRR. GIVEN LATE
TIMING AND POTENTIAL FOR THE SHRA/TSRA COMPLEX TO WEAKEN
FURTHER UPON ENCOUNTERING THE ALREADY WORKED OVER ATMOSPHERE
ACROSS MUCH OF THE REGION...WONT HOIST A FLOOD WATCH OVER THE
WEST FOR NOW AND CONTINUE TO MENTION IN THE HWO AT THIS POINT.
OTHERWISE BASICALLY REMOVED POPS OUT EAST TO INIT AND ADJUSTED
LOWS DOWN A TAD ESPCLY FAR WEST WHERE EXPECT MORE RAIN COOLER AIR
TO PUSH VALUES DOWN A LITTLE MORE.
PREVIOUS DISCUSSION AS OF 330 PM EDT TUESDAY...
WEATHER PATTERN HAS NOT CHANGED MUCH SINCE THIS MORNING...WITH A
STATIONARY FRONT SITUATED JUST NORTH OF THE OHIO RIVER...WHILE A
WARM FRONT STRETCHES FROM THE NORTH CAROLINA HIGHLANDS TO THE
SOUTHERN END OF THE OUTER BANKS. RADAR INDICATES THE DISTURBANCE
RIDING ALONG THE FRONT WHICH TRIGGERED HEAVY RAIN THIS MORNING AND
AFTERNOON ACROSS THE HIGHLANDS IS FINALLY PUSHING EAST...AFTER
DROPPING AN INCH OR MORE OF RAINFALL.
THIS EVENING...WEAK DISTURBANCES WILL PASS ACROSS THE CENTRAL
APPALACHIANS...TRIGGERING ROUNDS OF LIGHT TO OCCASIONALLY MODERATE
RAIN. THE MAIN CONCERN WILL BE AROUND MIDNIGHT...WHEN THE
THUNDERSTORM COMPLEX OVER SOUTHERN ILLINOIS APPROACHES OUR
WESTERN RIDGES. RAPID UPDATE MODELS THIS AFTERNOON ARE FOCUSING ON
THE COMPLEX ENTERING THE MOUNTAIN EMPIRE...PERHAPS CLIPPING AREAS
IN THE NORTH CAROLINA HIGHLANDS WHICH RECEIVED HEAVIER RAINFALL
TODAY. HOWEVER...ONLY SPOTTY RAINFALL IS EXPECTED UNTIL THEN...
AND MODELS AGREE THAT THE COMPLEX WILL PASS ACROSS OUR AREA
QUICKLY. HAVE THEREFORE OPTED TO FOREGO A FLASH FLOOD WATCH THIS
EVENING FOR THE NORTH CAROLINA HIGHLANDS...ALTHOUGH LOCALLY HEAVY
RAIN AND TRAINING OF STORMS IS POSSIBLE. WARM SOUTHWESTERLY FLOW
WILL KEEP TEMPERATURES ON THE MILD SIDE OVERNIGHT...HOLDING IN THE
MID 50S TO LOW 60S...APPROACHING RECORD HIGH MINIMUM TEMPERATURES
IN A FEW LOCATIONS. SEE THE CLIMATE SECTION BELOW FOR ADDITIONAL
DETAILS.
THE TRAIN OF SHOWER ACTIVITY WILL CONTINUE INTO WEDNESDAY AS UPPER
LEVEL DISTURBANCES PASS OVERHEAD. INSTABILITY WILL REMAIN MUTED
ACROSS THE EAST AS THE FRONT TO THE NORTH BEGINS TO SINK SOUTHWARD
AS A BACKDOOR COLD FRONT ACROSS THE PIEDMONT. MAY SEE A FEW
THUNDERSTORMS DEVELOP ACROSS THE MOUNTAINS DURING THE AFTERNOON
IN THE MORE UNSTABLE SOUTHWESTERLY FLOW...HOWEVER DO NOT SEE
STORMS HOLDING TOGETHER AS MUCH FURTHER EAST AS THEY RIDE INTO THE
WEDGE. UNDERCUT AFTERNOON TEMPERATURES IN THE EAST BY A FEW
DEGREES...WHILE STUCK CLOSE TO GUIDANCE ACROSS THE MOUNTAINS
WHERE CLOUDS MAY BREAK UP SOMEWHAT DURING LATE MORNING.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 315 PM EDT TUESDAY
BY THURSDAY MORNING...A BACKDOOR FRONT WILL HAVE PUSHED SOUTH OF OUR
FORECAST AREA ALLOWING A STABLE AIRMASS TO WEDGE DOWN THE EASTERN
PORTION OF OUR FORECAST AREA. LOWERED TEMPS A COUPLE OF DEGREE FOR
AREAS EXPECTED TO BE IN WEDGE...SUCH AS LYH.
DURING THE SHORT TERM PERIOD...THE UPPER LEVEL FLOW WILL TRANSITION
FROM ZONAL FLOW TO A SOUTHWEST FLOW IN ADVANCE OF A SHORTWAVE MOVING
THROUGH THE GREAT LAKES FRIDAY. THERE IS LOW CONFIDENCE IN THE
TIMING OF SHORTWAVES EMBEDDED THE DEVELOPING SOUTHWEST FLOW...BUT
THERE IS SOME AGREEMENT IN THE SHORT RANGE MODELS THAT WE MAY BE
BETWEEN SYSTEMS EARLY THURSDAY...KEEPING PRECIP CHANCES LOW.
THOSE CHANCES FOR PRECIP INCREASE THURSDAY AS A GOOD SURGE OF LOW
LEVEL THETA-E AIR ARRIVES FROM THE SOUTHWEST WITH AN INCREASING
SOUTHWESTERLY LOW LEVEL JET. ALOFT...AN UPPER LEVEL SHORTWAVE
EJECTING OUT OF THE SOUTHERN PLAINS ENTERS THE FAR WESTERN PORTION
OF OUR FORECAST AREA...HELPING TO INITIATE SHOWERS AND
STORMS...ESPECIALLY IN THE WEST.
A LOW LEVEL WEDGE CONTINUES IN THE EAST...AND WOULD EXPECT TO SEE A
LARGE RANGE IN TEMPS FOR HIGHS ON THURSDAY...WITH 60S IN THE VA
PIEDMONT (LYH AREA)...AND HIGHS NEAR 80 OUTSIDE OF THE WEDGE.
DEPENDING ON THE AMOUNT OF SUN...EXPECT ENOUGH INSTABILITY TO BE
REALIZED TO PRODUCE THUNDERSTORMS OUTSIDE OF THE WEDGE.
LOW LEVEL WEDGE ERODES LATE THURSDAY NIGHT AND FRIDAY...WITH THE
APPROACH OF A STRONG COLD FRONT THAT MOVES THROUGH DURING THE DAY
FRIDAY. THIS FRONT WILL INTERACT WITH A MOISTURE LADEN AIRMASS TO
SPARK A LINE OF SHOWERS AND STORMS. WITH FORECAST 0-6KM BULK SHEAR
IN EXCESS OF 35-40KTS...ORGANIZED STORMS POSSIBLE...AND WILL
CONTINUE TO MENTION THREAT OF POSSIBLE SEVERE STORMS IN HWO.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 315 PM EDT TUESDAY
THE LONG RANGE MODELS ARE IN GENERAL AGREEMENT EARLY IN THE LONG
TERM PERIOD THAT AN EASTERN U.S. TROF SATURDAY...SHIFTS EAST WITH A
SOUTHEAST RIDGE DEVELOPING SUNDAY.
THIS WILL KEEP DRY HIGH PRESSURE OVER THE AREA AND SLIGHTLY COOLER
TEMPS FOR THE WEEKEND.
AFTER SUNDAY...THERE ARE CONSIDERABLE DIFFERENCES ON THE EVOLUTION
OF A SOUTHERN STREAM SYSTEM POTENTIALLY IMPACTING OUR AREA EARLY
NEXT WEEK.
THE GFS IS WEAKER AND FASTER WITH THIS SYSTEM...LIFTING IT INTO THE
OHIO VALLEY BY THURSDAY. MEANWHILE THE ECMWF LIFTS THE SYSTEM OVER
OUR AREA...AND BUILDING A LOW LEVEL WEDGE OF HIGH PRESSURE BY THE
END OF THE LONG TERM PERIOD. THE CANADIAN IS IN BETTER AGREEMENT
WITH ECMWF RETURNING PRECIP INTO OUR AREA SUNDAY NIGHT INTO MONDAY.
AS A RESULT...INCREASED POPS SUNDAY NIGHT THROUGH MONDAY.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 645 PM EDT TUESDAY...
MOSTLY VFR CONDITIONS ARE EXPECTED INTO THE EVENING WITH POCKETS
OF MVFR IN SPOTTY RAIN SHOWERS MAINLY OVER THE MOUNTAINS. MAIN
CONCERN OVERNIGHT WITH STORM COMPLEX BACK ACROSS KENTUCKY AND
EXACTLY HOW FAR EAST IT WILL GET BEFORE WEAKENING OVERNIGHT.
LATEST HRRR BRINGS THIS FEATURE INTO THE WESTERN SLOPES AROUND
KBLF/KLWB SHORTLY AFTER MIDNIGHT BUT MOSTLY HEAVIER SHOWERS AT
THAT POINT GIVEN LACK OF INSTABILITY. THUS INCLUDING A PERIOD OF
MVFR CIGS OVER THE FAR WESTERN LOCATIONS AROUND MIDNIGHT WITH VCTS
MENTION ONLY AT KBLF. SHOWERS MAY ALSO SPREAD EAST TOWARD THE BLUE
RIDGE WITH ACCOMPANYING MVFR CIGS EXPECTED OUT TO KROA LATE.
PATCHY FOG ALONG WITH LOWER MVFR CIGS COULD ALSO FILL IN OUT EAST
AHEAD OF THE BACKDOOR FRONT ESPCLY AROUND KLYH WHERE SOME LOWER
STRATUS POSSIBLE LATE
OTHERWISE...FRONTAL BOUNDARY SITUATED TO THE NORTH OF
THE AREA WILL SINK SOUTH AS A BACKDOOR COLD FRONT ACROSS THE
PIEDMONT EARLY WEDNESDAY. EXPECT A NORTHEASTERLY WIND SHIFT AFTER
SUNRISE WEDNESDAY FOR KLYH...ALONG WITH MVFR/POSSIBLY IFR
STRATUS... WHICH WILL GRADUALLY LIFT IN THE AFTERNOON PENDING JUST
HOW FAR WEST LOW CLOUDS MAKE IT. ACROSS THE MOUNTAINS...
SOUTHWESTERLY FLOW WILL PERSIST INTO LATE AFTERNOON...AND MAY SEE
SHOWERS/THUNDERSTORMS DEVELOP DURING THE AFTERNOON IN THE MORE
UNSTABLE AIR AHEAD OF ANOTHER DISTURBANCE ARRIVING OVER THE WEST.
GUIDANCE REMAINS QUITE PESSIMISTIC WITH LOW CIGS OVER THE EAST
INTO WED AFTERNOON AND OVER THE WEST LATE IN THE DAY. SINCE
APPEARS OVERDONE...WILL KEEP MOSTLY MVFR LEVEL BASES FOR NOW WHILE
INCLUDING MORE IN THE WAY OF VSBY REDUCTIONS OVER THE MOUNTAINS
WEDNESDAY AFTERNOON WHERE OCNL MVFR VSBYS COULD OCCUR.
EXTENDED AVIATION DISCUSSION...
A PROLONGED PERIOD OF MVFR CONDITIONS LOOKS IN ORDER FROM
WEDNESDAY NIGHT INTO FRIDAY WITH A COLD FRONTAL PASSAGE EXPECTED
LATER FRIDAY. BEST SHOWER THREAT LIKELY WEDNESDAY EVENING AND
AGAIN MOUNTAINS LATE THURSDAY...FOLLOWED BY MORE WIDESPREAD
SHOWERS/STORMS FRIDAY JUST AHEAD OF THE FRONT WHEN IFR CIGS/VSBYS
COULD OCCUR.
COLD FRONT EXPECTED TO CLEAR THE REGION FRIDAY NIGHT- SATURDAY
MORNING WITH ANY SHOWERS SUBSIDING THOUGH SOME UPSLOPE MVFR CIGS
MAY LINGER INTO SATURDAY AT KBLF/KLWB. WIDESPREAD VFR THEN RETURNS
SATURDAY NIGHT AND SUNDAY UNDER HIGH PRESSURE BEHIND THE FRONT.
&&
.CLIMATE...
AS OF 400 AM EDT TUESDAY...
MILD TEMPERATURES ARE EXPECTED WEDNESDAY MORNING...WITH LOWS
ABOUT 10 TO 20 DEGREES ABOVE NORMAL. SOME RECORD WARM LOW
TEMPERATURES COULD BE BROKEN FOR APRIL 8TH.
STATION RECORD LOW/YEAR FORECAST LOW
ROANOKE 60/1991 59
LYNCHBURG 64/1908 59
DANVILLE 62/1954 60
BLACKSBURG 56/2001 55
BLUEFIELD 62/2001 57
LEWISBURG 59/2001 54
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/NF
NEAR TERM...JH/NF
SHORT TERM...PH
LONG TERM...PH
AVIATION...JH/NF/WP
CLIMATE...NF/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
713 PM EDT TUE APR 7 2015
.SYNOPSIS...
A WEAK FRONT JUST NORTH OF THE REGION WILL SLIP BACK SOUTH TO
ALONG THE BLUE RIDGE LATE TONIGHT INTO WEDNESDAY. THE BOUNDARY
WILL THEN LIFT BACK TO THE NORTH THURSDAY AHEAD OF A STRONG COLD
FRONT APPROACHING FROM THE WEST. THIS FRONT WILL FINALLY PUSH
THROUGH FROM THE WEST FRIDAY FOLLOWED BY HIGH PRESSURE FOR THE
WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 330 PM EDT TUESDAY...
WEATHER PATTERN HAS NOT CHANGED MUCH SINCE THIS MORNING...WITH A
STATIONARY FRONT SITUATED JUST NORTH OF THE OHIO RIVER...WHILE A
WARM FRONT STRETCHES FROM THE NORTH CAROLINA HIGHLANDS TO THE
SOUTHERN END OF THE OUTER BANKS. RADAR INDICATES THE DISTURBANCE
RIDING ALONG THE FRONT WHICH TRIGGERED HEAVY RAIN THIS MORNING AND
AFTERNOON ACROSS THE HIGHLANDS IS FINALLY PUSHING EAST...AFTER
DROPPING AN INCH OR MORE OF RAINFALL.
THIS EVENING...WEAK DISTURBANCES WILL PASS ACROSS THE CENTRAL
APPALACHIANS...TRIGGERING ROUNDS OF LIGHT TO OCCASIONALLY MODERATE
RAIN. THE MAIN CONCERN WILL BE AROUND MIDNIGHT...WHEN THE
THUNDERSTORM COMPLEX OVER SOUTHERN ILLINOIS APPROACHES OUR
WESTERN RIDGES. RAPID UPDATE MODELS THIS AFTERNOON ARE FOCUSING ON
THE COMPLEX ENTERING THE MOUNTAIN EMPIRE...PERHAPS CLIPPING AREAS
IN THE NORTH CAROLINA HIGHLANDS WHICH RECEIVED HEAVIER RAINFALL
TODAY. HOWEVER...ONLY SPOTTY RAINFALL IS EXPECTED UNTIL THEN...
AND MODELS AGREE THAT THE COMPLEX WILL PASS ACROSS OUR AREA
QUICKLY. HAVE THEREFORE OPTED TO FOREGO A FLASH FLOOD WATCH THIS
EVENING FOR THE NORTH CAROLINA HIGHLANDS...ALTHOUGH LOCALLY HEAVY
RAIN AND TRAINING OF STORMS IS POSSIBLE. WARM SOUTHWESTERLY FLOW
WILL KEEP TEMPERATURES ON THE MILD SIDE OVERNIGHT...HOLDING IN THE
MID 50S TO LOW 60S...APPROACHING RECORD HIGH MINIMUM TEMPERATURES
IN A FEW LOCATIONS. SEE THE CLIMATE SECTION BELOW FOR ADDITIONAL
DETAILS.
THE TRAIN OF SHOWER ACTIVITY WILL CONTINUE INTO WEDNESDAY AS UPPER
LEVEL DISTURBANCES PASS OVERHEAD. INSTABILITY WILL REMAIN MUTED
ACROSS THE EAST AS THE FRONT TO THE NORTH BEGINS TO SINK SOUTHWARD
AS A BACKDOOR COLD FRONT ACROSS THE PIEDMONT. MAY SEE A FEW
THUNDERSTORMS DEVELOP ACROSS THE MOUNTAINS DURING THE AFTERNOON
IN THE MORE UNSTABLE SOUTHWESTERLY FLOW...HOWEVER DO NOT SEE
STORMS HOLDING TOGETHER AS MUCH FURTHER EAST AS THEY RIDE INTO THE
WEDGE. UNDERCUT AFTERNOON TEMPERATURES IN THE EAST BY A FEW
DEGREES...WHILE STUCK CLOSE TO GUIDANCE ACROSS THE MOUNTAINS
WHERE CLOUDS MAY BREAK UP SOMEWHAT DURING LATE MORNING.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 315 PM EDT TUESDAY
BY THURSDAY MORNING...A BACKDOOR FRONT WILL HAVE PUSHED SOUTH OF OUR
FORECAST AREA ALLOWING A STABLE AIRMASS TO WEDGE DOWN THE EASTERN
PORTION OF OUR FORECAST AREA. LOWERED TEMPS A COUPLE OF DEGREE FOR
AREAS EXPECTED TO BE IN WEDGE...SUCH AS LYH.
DURING THE SHORT TERM PERIOD...THE UPPER LEVEL FLOW WILL TRANSITION
FROM ZONAL FLOW TO A SOUTHWEST FLOW IN ADVANCE OF A SHORTWAVE MOVING
THROUGH THE GREAT LAKES FRIDAY. THERE IS LOW CONFIDENCE IN THE
TIMING OF SHORTWAVES EMBEDDED THE DEVELOPING SOUTHWEST FLOW...BUT
THERE IS SOME AGREEMENT IN THE SHORT RANGE MODELS THAT WE MAY BE
BETWEEN SYSTEMS EARLY THURSDAY...KEEPING PRECIP CHANCES LOW.
THOSE CHANCES FOR PRECIP INCREASE THURSDAY AS A GOOD SURGE OF LOW
LEVEL THETA-E AIR ARRIVES FROM THE SOUTHWEST WITH AN INCREASING
SOUTHWESTERLY LOW LEVEL JET. ALOFT...AN UPPER LEVEL SHORTWAVE
EJECTING OUT OF THE SOUTHERN PLAINS ENTERS THE FAR WESTERN PORTION
OF OUR FORECAST AREA...HELPING TO INITIATE SHOWERS AND
STORMS...ESPECIALLY IN THE WEST.
A LOW LEVEL WEDGE CONTINUES IN THE EAST...AND WOULD EXPECT TO SEE A
LARGE RANGE IN TEMPS FOR HIGHS ON THURSDAY...WITH 60S IN THE VA
PIEDMONT (LYH AREA)...AND HIGHS NEAR 80 OUTSIDE OF THE WEDGE.
DEPENDING ON THE AMOUNT OF SUN...EXPECT ENOUGH INSTABILITY TO BE
REALIZED TO PRODUCE THUNDERSTORMS OUTSIDE OF THE WEDGE.
LOW LEVEL WEDGE ERODES LATE THURSDAY NIGHT AND FRIDAY...WITH THE
APPROACH OF A STRONG COLD FRONT THAT MOVES THROUGH DURING THE DAY
FRIDAY. THIS FRONT WILL INTERACT WITH A MOISTURE LADEN AIRMASS TO
SPARK A LINE OF SHOWERS AND STORMS. WITH FORECAST 0-6KM BULK SHEAR
IN EXCESS OF 35-40KTS...ORGANIZED STORMS POSSIBLE...AND WILL
CONTINUE TO MENTION THREAT OF POSSIBLE SEVERE STORMS IN HWO.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 315 PM EDT TUESDAY
THE LONG RANGE MODELS ARE IN GENERAL AGREEMENT EARLY IN THE LONG
TERM PERIOD THAT AN EASTERN U.S. TROF SATURDAY...SHIFTS EAST WITH A
SOUTHEAST RIDGE DEVELOPING SUNDAY.
THIS WILL KEEP DRY HIGH PRESSURE OVER THE AREA AND SLIGHTLY COOLER
TEMPS FOR THE WEEKEND.
AFTER SUNDAY...THERE ARE CONSIDERABLE DIFFERENCES ON THE EVOLUTION
OF A SOUTHERN STREAM SYSTEM POTENTIALLY IMPACTING OUR AREA EARLY
NEXT WEEK.
THE GFS IS WEAKER AND FASTER WITH THIS SYSTEM...LIFTING IT INTO THE
OHIO VALLEY BY THURSDAY. MEANWHILE THE ECMWF LIFTS THE SYSTEM OVER
OUR AREA...AND BUILDING A LOW LEVEL WEDGE OF HIGH PRESSURE BY THE
END OF THE LONG TERM PERIOD. THE CANADIAN IS IN BETTER AGREEMENT
WITH ECMWF RETURNING PRECIP INTO OUR AREA SUNDAY NIGHT INTO MONDAY.
AS A RESULT...INCREASED POPS SUNDAY NIGHT THROUGH MONDAY.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 645 PM EDT TUESDAY...
MOSTLY VFR CONDITIONS ARE EXPECTED INTO THE EVENING WITH POCKETS
OF MVFR IN SPOTTY RAIN SHOWERS MAINLY OVER THE MOUNTAINS. MAIN
CONCERN OVERNIGHT WITH STORM COMPLEX BACK ACROSS KENTUCKY AND
EXACTLY HOW FAR EAST IT WILL GET BEFORE WEAKENING OVERNIGHT.
LATEST HRRR BRINGS THIS FEATURE INTO THE WESTERN SLOPES AROUND
KBLF/KLWB SHORTLY AFTER MIDNIGHT BUT MOSTLY HEAVIER SHOWERS AT
THAT POINT GIVEN LACK OF INSTABILITY. THUS INCLUDING A PERIOD OF
MVFR CIGS OVER THE FAR WESTERN LOCATIONS AROUND MIDNIGHT WITH VCTS
MENTION ONLY AT KBLF. SHOWERS MAY ALSO SPREAD EAST TOWARD THE BLUE
RIDGE WITH ACCOMPANYING MVFR CIGS EXPECTED OUT TO KROA LATE.
PATCHY FOG ALONG WITH LOWER MVFR CIGS COULD ALSO FILL IN OUT EAST
AHEAD OF THE BACKDOOR FRONT ESPCLY AROUND KLYH WHERE SOME LOWER
STRATUS POSSIBLE LATE
OTHERWISE...FRONTAL BOUNDARY SITUATED TO THE NORTH OF
THE AREA WILL SINK SOUTH AS A BACKDOOR COLD FRONT ACROSS THE
PIEDMONT EARLY WEDNESDAY. EXPECT A NORTHEASTERLY WIND SHIFT AFTER
SUNRISE WEDNESDAY FOR KLYH...ALONG WITH MVFR/POSSIBLY IFR
STRATUS... WHICH WILL GRADUALLY LIFT IN THE AFTERNOON PENDING JUST
HOW FAR WEST LOW CLOUDS MAKE IT. ACROSS THE MOUNTAINS...
SOUTHWESTERLY FLOW WILL PERSIST INTO LATE AFTERNOON...AND MAY SEE
SHOWERS/THUNDERSTORMS DEVELOP DURING THE AFTERNOON IN THE MORE
UNSTABLE AIR AHEAD OF ANOTHER DISTURBANCE ARRIVING OVER THE WEST.
GUIDANCE REMAINS QUITE PESSIMISTIC WITH LOW CIGS OVER THE EAST
INTO WED AFTERNOON AND OVER THE WEST LATE IN THE DAY. SINCE
APPEARS OVERDONE...WILL KEEP MOSTLY MVFR LEVEL BASES FOR NOW WHILE
INCLUDING MORE IN THE WAY OF VSBY REDUCTIONS OVER THE MOUNTAINS
WEDNESDAY AFTERNOON WHERE OCNL MVFR VSBYS COULD OCCUR.
EXTENDED AVIATION DISCUSSION...
A PROLONGED PERIOD OF MVFR CONDITIONS LOOKS IN ORDER FROM
WEDNESDAY NIGHT INTO FRIDAY WITH A COLD FRONTAL PASSAGE EXPECTED
LATER FRIDAY. BEST SHOWER THREAT LIKELY WEDNESDAY EVENING AND
AGAIN MOUNTAINS LATE THURSDAY...FOLLOWED BY MORE WIDESPREAD
SHOWERS/STORMS FRIDAY JUST AHEAD OF THE FRONT WHEN IFR CIGS/VSBYS
COULD OCCUR.
COLD FRONT EXPECTED TO CLEAR THE REGION FRIDAY NIGHT- SATURDAY
MORNING WITH ANY SHOWERS SUBSIDING THOUGH SOME UPSLOPE MVFR CIGS
MAY LINGER INTO SATURDAY AT KBLF/KLWB. WIDESPREAD VFR THEN RETURNS
SATURDAY NIGHT AND SUNDAY UNDER HIGH PRESSURE BEHIND THE FRONT.
&&
.CLIMATE...
AS OF 400 AM EDT TUESDAY...
MILD TEMPERATURES ARE EXPECTED WEDNESDAY MORNING...WITH LOWS
ABOUT 10 TO 20 DEGREES ABOVE NORMAL. SOME RECORD WARM LOW
TEMPERATURES COULD BE BROKEN FOR APRIL 8TH.
STATION RECORD LOW/YEAR FORECAST LOW
ROANOKE 60/1991 59
LYNCHBURG 64/1908 59
DANVILLE 62/1954 60
BLACKSBURG 56/2001 55
BLUEFIELD 62/2001 57
LEWISBURG 59/2001 54
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/NF
NEAR TERM...NF
SHORT TERM...PH
LONG TERM...PH
AVIATION...JH/NF/WP
CLIMATE...NF/WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
337 PM CDT MON APR 6 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 337 PM CDT MON APR 6 2015
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED BROAD UPPER TROUGHING ALONG THE WEST COAST OF THE
U.S....RIDGING ACROSS THE PLAINS AND THEN ZONAL FLOW ACROSS THE
GREAT LAKES AND NEW ENGLAND. A STATIONARY SURFACE FRONTAL ZONE
EXISTS UNDERNEATH THE RIDGING AND ZONAL FLOW NEAR I-80...WITH A MID
LEVEL FRONTOGENESIS AXIS WELL TO THE NORTH ACROSS CENTRAL MN AND
NORTHERN WI. SOME PRECIPITATION WAS FALLING OUT OF THIS AXIS...BUT
A NORTHEAST FLOW OF CANADIAN DRY AIR FROM HIGH PRESSURE IN ONTARIO
HAS DIMINISHED MUCH OF THE PRECIPITATION. THE 12Z GRB SOUNDING AND
ESPECIALLY THE INL SOUNDING SHOWED THAT DRY AIR NICELY. SOME OF THAT
DRY AIR INFILTRATED INTO THE FORECAST AREA THIS MORNING TO CLEAR
SKIES OUT FROM THE STRATUS. HOWEVER...MID AND HIGH CLOUDS WERE
SPREADING BACK OVER THE AREA FROM A BROAD WARM ADVECTION REGIME
UNDER THE UPPER RIDGE...AND THEN SOME LOW STRATUS WAS TRYING TO BACK
INTO THE AREA FROM NORTHEAST WI. A FEW SHOWERS AND STORMS HAVE BEEN
GOING ON NEAR WATERLOO IA MARCHING EAST-NORTHEAST...ASSOCIATED WITH
A WEAK SHORTWAVE INTERACTING WITH THE WARM/MOIST ADVECTION. QUITE
THE LOW LEVEL THERMAL TEMPERATURE GRADIENT EXITS ACROSS THE FORECAST
AREA. PER RAP 925MB TEMPS... READINGS NORTH OF HIGHWAY 29 ARE AROUND
0C COMPARED TO 8C OVER NORTHERN IA AND SOUTHERN WI. FARTHER
SOUTHWEST 20C PLUS 925MB READINGS EXISTS IN WESTERN KS.
THE UPPER RIDGING OVER THE PLAINS IS PROGGED TO PROGRESS OVER THE
FORECAST AREA OVER THE NEXT 24 HOURS IN RESPONSE TO THE TROUGH ALONG
THE WEST COAST MOVING INLAND SLIGHTLY. THIS WILL PUT THE FORECAST
AREA IN A WARM/MOISTURE ADVECTION ZONE ALOFT. ISENTROPIC LIFT FIELDS
SHOW THIS NICELY...ESPECIALLY DURING THE DAY TUESDAY AND EVEN MORESO
IN THE AFTERNOON WEST OF THE MS RIVER ON 290-300K SURFACES.
THUS...WE SHOULD SEE A CONTINUOUS INCREASE AND THICKENING OF CLOUD
COVER. AN EAST TO NORTHEAST LOW LEVEL FLOW BRINGING IN DRIER AIR
FROM ONTARIO WILL HAMPER SOME OF THE PRECIPITATION PRODUCTION...OR
MAKE IT SPOTTY...UNTIL TUESDAY AFTERNOON WHEN PRECIPITABLE WATER
SURGES UP TO 0.75 TO 1 INCH. THEREFORE HIGHEST PRECIPITATION CHANCES
ARE PLACED IN THE LATE TUE AFTERNOON TIME PERIOD.
THE INCREASE IN CLOUD COVER WOULD HELP TO KEEP TEMPERATURES UP.
HOWEVER...THE EASTERLY FLOW OF COOLER DRY AIR IN CONJUNCTION WITH
SPOTTY PRECIPITATION WILL WORK TOGETHER TO KNOCK TEMPERATURES DOWN.
AS SUCH...925MB TEMPS FALL TO -2C NORTH TO +4C SOUTH BY 12Z TUE AND
LINGER NEAR THERE THROUGH MUCH OF TUESDAY. READINGS MAY STRUGGLE TO
CLIMB MUCH ON TUESDAY WITH LIMITED SUNSHINE...AND THE MORE
WIDESPREAD LATE AFTERNOON RAIN NOT HELPING MATTERS.
THE AFOREMENTIONED TEMPERATURES BRING ABOUT PRECIPITATION TYPE
CONCERNS ACROSS TAYLOR/CLARK COUNTY WHERE THE COLDEST AIR EXISTS.
SURFACE TEMPERATURES LOOK TO FALL BACK BELOW FREEZING TONIGHT. FOR
THE EVENING ICE IS SUGGESTED IN THE CLOUDS...SO THERE COULD BE A
RAIN/SNOW MIX. THEN DURING THE OVERNIGHT AND MUCH OF TUESDAY
MORNING...THE ICE IN THE CLOUDS DEPARTS TO THE NORTHEAST...LEAVING
THE POTENTIAL FOR FREEZING RAIN WITH ANY PRECIPITATION.
HOWEVER...ITS POSSIBLE THAT THE LOSS OF ICE MAY END UP ENDING THE
PRECIPITATION ENTIRELY AS SUGGESTED BY THE 06.12Z GFS.
THEREFORE...HAVE NOT ISSUED ANY WINTER WEATHER OR FREEZING RAIN
ADVISORY AT THIS TIME.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 337 PM CDT MON APR 6 2015
THERE ARE TWO MAIN PERIODS OF WEATHER FOCUS...TUESDAY NIGHT AND
LATE WEDNESDAY INTO THURSDAY NIGHT.
A SHORTWAVE TROUGH IS PROGGED TO CROSS MINNESOTA AND WISCONSIN
TUESDAY NIGHT...BRINGING WITH IT A DECENT SURGE OF 850MB MOISTURE
TRANSPORT / ISENTROPIC LIFT. MOISTURE SHOULD BE PLENTIFUL WITH
PRECIPITABLE WATER OF 0.75-1 INCH AND SATURATED SOUNDINGS. THEREFORE
CONDITIONS LOOK FAVORABLE FOR RAIN AND RAISED CHANCES UP TO 80. BEST
JUXTAPOSITION OF LIFT IS SITUATED SOUTH OF I-90 DURING THE EVENING.
ADDITIONALLY...WITH MUCAPE VALUES IN 200-500 J/KG RANGE DURING THE
EVENING ROOTED ABOVE 850MB AND LITTLE CAP...EXPECTING AT LEAST
ISOLATED THUNDERSTORMS TO OCCUR. PRECIPITATION SHOULD DIMINISH WEST
TO EAST AFTER MIDNIGHT AS THE LIFT MOVES OFF TO THE EAST AND
SUBSIDENCE COMES IN. PRECIPITATION TYPE FOR THE MOST PART LOOKS TO
BE RAIN WITH PLENTY OF WARM AIR IN PLACE...EXCEPT FOR TAYLOR COUNTY
SHOULD THE PRECIPITATION GET UP THERE. IN TAYLOR COUNTY...THE AIR
MAY BE COLD ENOUGH TO ALLOW FOR SLEET OR FREEZING RAIN.
A BRIEF BREAK LOOKS TO OCCUR FOR MUCH OF THE DAY WEDNESDAY...UNTIL
THE LATER AFTERNOON HOURS. THIS IS WHEN THE TROUGHING ALONG THE U.S.
WEST COAST BEGINS THE MARCH TOWARDS THE PLAINS...PUSHING ANOTHER
SURGE OF 850MB MOISTURE TRANSPORT AND ISENTROPIC LIFT INTO THE
FORECAST AREA. PRECIPITABLE WATER ALSO CLIMBS BACK TO 0.75-1 INCH
AFTER FALLING TO NEAR 0.5 INCH DURING THE MORNING. THE SURGE OF
MOISTURE TRANSPORT IS MORE IMPRESSIVE FOR WEDNESDAY NIGHT COMPARED
TO TUESDAY NIGHT...AND IT APPEARS EVERYWHERE SHOULD PICK OF
PRECIPITATION. ANTICIPATING RAIN TO BE THE MAIN PRECIPITATION TYPE
WITH ANY MIXED PRECIPITATION STAYING JUST NORTH OF THE FORECAST
AREA. SHOULD SEE SOME THUNDERSTORMS AGAIN SOUTH OF I-90 AS MUCAPE
ABOVE ANY ELEVATED CAPPING INCREASES TO 200-500 J/KG.
AS WE HEAD INTO THURSDAY...MODELS BEGIN TO SPREAD OUT ON THE SPEED
AND STRENGTH OF THE UPPER TROUGH...IMPACTING THE TRACK OF THE
SURFACE SYSTEM AND WARM SECTOR. THE ECMWF HAS BEEN HOLDING FAIRLY
STEADY WITH A MORE POSITIVE TILT TROUGH AND FARTHER SOUTHEAST
SURFACE LOW. ON THE OTHER HAND...THE 06.12Z GFS/CANADIAN/NAM ARE
MORE NEUTRAL AND EVEN NEGATIVE TILT IN THE NAM...RESULTING IN A
STRONGER SURFACE LOW. HARD TO SAY WHAT SCENARIO WILL PAN OUT...BUT
WITH THE ECMWF ENSEMBLE MEAN SIMILAR TO THE ECMWF...FEEL THE ECMWF
MAY BE MORE LIKELY TO WORK OUT. IN ANY EVENT...PRECIPITATION LOOKS
LIKE A GOOD BET TO CONTINUE ON THURSDAY...BUT OF A LIGHTER VARIETY
AS THE FORCING DIMINISHES TO JUST THE DPVA FROM THE UPPER TROUGH.
TYPE LOOKS TO HOLD AS RAIN. AGAIN THUNDERSTORMS ARE POSSIBLE SOUTH
OF I-90...AND IF THE FARTHER NORTHWEST 06.12Z CANADIAN/GFS PAN OUT
COULD EVEN SEE A SEVERE RISK IN FAR NORTHEAST IA/SOUTHWEST WI.
SOMETHING TO MONITOR. TEMPERATURES EXTREMELY TRICKY FOR THURSDAY AS
THEY DEPEND ON THE LOW TRACK. FOLLOWED A MODEL CONSENSUS FOR NOW.
THURSDAY NIGHT IS DOMINATED BY A COLD CONVEYOR BELT IMPACTING THE
NORTHWEST HALF OF THE FORECAST AREA...WHILE A DRY SLOT ACCOMPANYING
THE UPPER TROUGH TRIES TO MOVE THROUGH THE SOUTHEAST HALF. UNDER THE
COLD CONVEYOR BELT COULD SEE PRECIPITATION MIX WITH OR CHANGE OVER
TO SNOW...ESPECIALLY AS THE NIGHT WEARS ON AS TEMPERATURES COOL.
HOWEVER...BY THE TIME PRECIPITATION BEGINS TO SWITCH OVER...IT COULD
ALSO BE ENDING. THUS...NO SNOW ACCUMULATION IS ANTICIPATED AT THIS
TIME.
STILL KEPT SOME PRECIPITATION CHANCES IN FOR FRIDAY BASED ON A MODEL
CONSENSUS BUT NEW 06.12Z ECMWF/GFS WOULD SUGGEST A DRIER FORECAST
AND OUR FORECAST MAY BE ABLE TO BE DRIED OUT. ALTHOUGH COOL AIR
COMES IN BEHIND THE UPPER TROUGH FOR FRIDAY...POTENTIAL EXISTS FOR
MORE SUN COMPARED TO THURSDAY AND THUS HIGHS FOR MANY LOCATIONS END
UP SIMILAR.
FOR THE WEEKEND INTO EARLY NEXT WEEK. GOOD MODEL AGREEMENT EXISTS
AMONGST THE 06.12Z GFS/ECMWF/CANADIAN FOR UPPER RIDGING TO BUILD
INTO THE AREA FRIDAY NIGHT AND SATURDAY...RESULTING IN DRY
CONDITIONS. FRIDAY NIGHT COULD BE ON THE COOL SIDE WITH SURFACE HIGH
IN PLACE AND CLEARING. MAY EVEN END UP WITH SOME RADIATION FOG.
TEMPERATURES SHOULD REBOUND NICELY ON SATURDAY WITH SUN. THEN ON
SUNDAY AND MONDAY ANOTHER TROUGH THAT FORMS OVER THE WESTERN U.S.
LIFTS INTO/AFFECTS THE REGION. AS A RESULT PRECIPITATION CHANCES
RETURN. TYPE FOR THE MOST PART SHOULD BE RAIN. WARM ADVECTION HELPS
TO PUSH TEMPERATURES TO NEAR OR SLIGHTLY ABOVE SEASONABLE NORMALS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1243 PM CDT MON APR 6 2015
CURRENT RADAR MOSAIC ACROSS THE REGION SHOWING A BAND OF
CONVECTION ACROSS CENTRAL IA MOVING EAST AHEAD OF A MID-LEVEL
TROUGH PUSHING INTO WESTERN IA. PLAN ON THIS CONVECTION TO STAY
WELL SOUTH OF THE TAF SITES. MEANWHILE...DRY EASTERLY SURFACE FLOW
IS WORKING TO HOLD OFF STRATUS TO THE NORTH AND SOUTH OF THE
KRST/KLSE TAF SITE. EXPECT INCREASE IN ALTOCUMULUS GOING INTO
THIS AFTERNOON AHEAD OF THE TROUGH PUSHING INTO IOWA. WITH BETTER
FORCING FOR SHOWERS REMAINING SOUTH OF THE TAF SITES...WILL GO
WITH VCSH AT KRST/KLSE OVERNIGHT INTO TUESDAY MORNING.
MEANWHILE...EXPECTING MVFR/STRATUS CLOUD TO FILL IN AGAIN AFTER
01Z...LASTING THROUGH TUESDAY MORNING. PLAN ON SURFACE WINDS TO
REMAIN EASTERLY THROUGH THE PERIOD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1004 AM CDT MON APR 6 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CDT MON APR 6 2015
AT 3 AM...A BAND OF RAIN AND SNOW EXTENDED FROM TAMARACK MINNESOTA
EAST SOUTHEAST TO MENOMINEE WISCONSIN. THIS BAND OF PRECIPITATION
WAS CO-LOCATED WITH A BAND OF 700 TO 600 MB FRONTOGENETIC FORCING.
THE 06.00Z MESO AND DETERMINISTIC MODELS ARE IN GOOD AGREEMENT
THAT THIS FORCING WILL MOVE SOUTH INTO TAYLOR COUNTY THIS MORNING
AND GRADUALLY WEAKEN. THE PRECIPITATION MAY INITIALLY BE SNOW
EARLY THIS MORNING...BUT AS THE BOUNDARY LAYER WARMS AND THERE IS
A LOSS OF ICE CRYSTALS FROM ALOFT...THE SNOW WILL TRANSITION
QUICKLY TO RAIN. THIS BAND WILL THEN INTENSIFY AND DEEPEN LATE
THIS AFTERNOON AND TONIGHT AS THE FRONTOGENETIC BAND WILL EXTEND
FROM 800 TO 500 MB. SOUNDINGS AT THIS TIME...SHOW VERY LITTLE
ICING FROM ALOFT...THUS...THE PRECIPITATION WILL BE LIQUID. THIS
MAY PRESENT AN ISSUE IF THE TEMPERATURES ARE BELOW FREEZING. MANY
OF THE MOS GUIDANCES SUGGEST THAT THE TEMPERATURES WILL FALL INTO
THE UPPER 20S IN TAYLOR AND CLARK COUNTIES IN NORTH-CENTRAL
WISCONSIN. HOWEVER THIS DATA HAS BEEN RUNNING A BIT TOO COLD THE
LAST COUPLE OF NIGHTS...SO CONFIDENCE IS NOT THAT HIGH FOR
FREEZING RAIN. IN ADDITION...THE FROST IS OUT OF THE GROUND...IT
MAKES IT PROBLEMATIC ON WHAT THE EFFECT WILL BE ON ROADS. DUE TO
THIS...OPTED AT THIS TIME TO MENTION FREEZING RAIN...BUT MENTIONED
THE ICING ON ELEVATED SURFACES. THIS WOULD INCLUDE BRIDGES.
MEANWHILE FURTHER SOUTH...A 900 TO 700 MB BAND OF FRONTOGENETIC
FORCING WILL DEVELOP ALONG AND SOUTH OF INTERSTATE 94 AS A LOW
MOVES INTO THE CENTRAL PLAINS LATE THIS AFTERNOON AND TONIGHT. IN
ADDITION...THERE WILL BE WEAK 925 AND 850 MB MOISTURE TRANSPORT
INTO THE REGION. THIS RESULTS IN A SATURATED AIR MASS UP TO 700 MB
CO-LOCATED SOME WEAK OMEGA. THIS WILL RESULT IN THE DEVELOPMENT OF
LIGHT RAIN ACROSS THE REMAINDER OF THE AREA. ONE THING THAT WILL
HAVE TO BE WATCHED IS THAT THE ECMWF SUGGESTS THAT A DRY EASTERLY
FLOW MAY INHIBIT THE PRECIPITATION FROM DEVELOPING ACROSS THE
SOUTHERN HALF OF WISCONSIN. SINCE THIS IS THE ONLY MODEL SHOWING
THIS AND IT IS A RELATIVELY NEW DEVELOPMENT JUST LEFT THE LOW
LIKELY PRECIPITATION CHANCES GOING FOR THE ENTIRE AREA TONIGHT.
ANOTHER CHANGE TO THE FORECAST TONIGHT WAS TO TAKE OUT THE
THUNDERSTORM CHANCES SOUTH OF INTERSTATE 90. THE 06.00Z MODELS
ARE KEEPING THE MOST UNSTABLE CAPES WELL SOUTH OF THE AREA. THIS
SEEMS REASONABLE CONSIDERING THE STRENGTH OF THE WINDS ALOFT AND
THAT THE LOW IS STILL LOCATED WELL OF THE SOUTHWEST OF THE AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM CDT MON APR 6 2015
ON TUESDAY MORNING...BOTH THE GFS AND ECMWF ARE SHOWING THAT THE
DRY EASTERLY FLOW NORTH OF THE WARM FRONT AND THAT THE BEST 850 MB
MOISTURE TRANSPORT WILL REMAIN WELL SOUTHEAST AND SOUTHWEST OF THE
AREA. AS A RESULT...THEY HAVE MUCH OF WISCONSIN DRY. MEANWHILE THE
GEM AND NAM HAS THIS DRY AIR MUCH FURTHER NORTH...THUS...THEY ONLY
HAVE THE NORTHERN HALF OF WISCONSIN DRY. SINCE THERE WAS DECENT
CONSISTENCY IN THE NORTHERN HALF OF THE AREA...LOWERED THE
PRECIPITATION CHANCES FROM LIKELY TO CHANCE. IF THIS TREND
CONTINUES...MAY HAVE TO FURTHER DRY OUT WISCONSIN.
FROM TUESDAY AFTERNOON THOUGH TUESDAY NIGHT...WEAK TO MODERATE
925 MB AND 850 MB MOISTURE TRANSPORT MOVES INTO THE THE AREA. AS
THIS OCCURS...SOUNDINGS SATURATE QUICKLY ACROSS WISCONSIN...THUS
ALLOWING RAIN TO SPREAD INTO THE AREA. IN ADDITION...MOST UNSTABLE
CAPES WILL CLIMB UP TO 500 MB ALONG AND SOUTH OF INTERSTATE 90 ON
TUESDAY AFTERNOON. THIS WILL RESULT IN THE POTENTIAL FOR ISOLATED
THUNDERSTORMS. THE 0-6 KM SHEAR IS OVER 60 KNOTS. HOWEVER MUST OF
THIS IS DUE TO THE EAST WINDS AT THE SURFACE. LOOKING AT THE WINDS
ABOVE THIS STABLE LAYER...THE SHEAR IS LESS THAN 30 KNOTS...THUS
NOT CONCERNED WITH ANY SEVERE WEATHER. ANOTHER CONCERN FOR TUESDAY
NIGHT IS THAT THE SURFACE TEMPERATURES MAY BE BELOW FREEZING
ACROSS CLARK AND TAYLOR COUNTIES. WITH THE SOUNDINGS SHOWING
INTRODUCTION OF ICE CRYSTALS FROM ALOFT...MAY HAVE TO CONTEND WITH
ANOTHER ROUND OF FREEZING RAIN. LIKE TONIGHT...THINKING THAT THE
THE BEST CHANCES OF ICING WILL BE ON ELEVATED SURFACES.
FROM WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...THE MODELS SHOW THAT
A NEGATIVELY TILTED SHORT WAVE TROUGH WILL AFFECT THE AREA. THIS
SYSTEM WILL BRING GULF OF MEXICO MOISTURE AS FAR NORTH AS THE
INTERSTATE 90 CORRIDOR. THIS WILL AIR IN THE DEVELOPMENT OF MOST
UNSTABLE UP TO 1500 J/KG SOUTH OF THIS INTERSTATE. THE 0-6KM SHEAR
CLIMB UP TO 50 KNOTS. MUCH OF THIS SHEAR IS LOCATED BELOW 3 KM...
SO MAY HAVE TO WATCH FOR THE POTENTIAL OF DAMAGING WINDS FROM
THURSDAY AFTERNOON INTO THURSDAY EVENING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 1004 AM CDT MON APR 6 2015
UPDATE FROM PREVIOUS DISCUSSION...LATEST SATELLITE IMAGERY
SHOWING A CLEARING SLOT WORKING FROM WEST TO EAST ACROSS SOUTHERN
WI. THIS IS IN RESPONSE TO DRY EASTERLY LOW LEVEL FLOW. RAP MODEL
SHOWS THIS CLEARING TREND A BIT MORE MUDDLED ACROSS SOUTHEAST MN.
WILL HAVE TO KEEP AND EYE ON LOW CLOUD TRENDS BASED ON THIS
ANALYSIS. FOR NOW...BACKED OFF ON LOW/MVFR CLOUD COVER AT KLSE AND
WENT VFR THROUGH 01Z THIS EVENING. KEPT MVFR CLOUD COVER AT KRST
WITH CLEARING SIGNAL NOT AS STRONG THERE. LIGHT RAIN WILL
OVERSPREAD THE REGION BY EARLY THIS EVENING...WITH LIGHT RAIN
LIKELY AT BOTH TAF SITES AROUND 00Z. OTHERWISE...APPEARS MVFR
CLOUD WILL TAKE HOLD AGAIN WITH THE ONSET OF THE RAIN...WITH KRST
LOOKING LIKE IT WILL SLIP INTO IFR AFTER 06Z AS THE MOIST LOWER
BOUNDARY LAYER COOLS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1201 AM MDT MON APR 6 2015
.UPDATE...
ISSUED AT 830 PM MDT SUN APR 5 2015
CRITICAL FIRE WEATHER CONDITIONS ARE EASING THIS EVENING AS WINDS
STEADILY DECREASE AND HUMIDITIES IMPROVE. THUS...ALLOWED THE RED
FLAG WARNING TO EXPIRE ON TIME. INCREASED CLOUD COVER SLIGHTLY FOR
TONIGHT AS A FAIRLY BROAD CIRRUS SHIELD HAS MOVED UP FROM THE
SOUTHWEST. OTHERWISE...THE FORECAST LOOKS TO BE IN GOOD SHAPE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 228 PM MDT SUN APR 5 2015
THE PATTERN WILL AMPLIFY EARLY IN THE WEEK AS THE NEXT TROUGH CARVES
INTO THE WEST COAST. THE DOWNSTREAM IMPACTS WILL BE FOR FLOW TO
BECOME MORE SOUTHWESTERLY THRU TUESDAY ALONG WITH THE INITIAL
IMPULSES AND ASSOCIATED PACIFIC MOISTURE EJECTING INTO THE THE NRN
ROCKIES. BEFORE THEN...SATELLITE PIX THIS AFTERNOON SHOW THE CIRRUS
SHIELD SEEN EARLIER THIS MORNING ALL BUT GONE ACROSS THE CWFA...
WHICH HAS RESULTED IN DEEP MIXING IN THE BL THIS AFTERNOON. WIND
GUSTS OF 25-35 MPH AND HUMIDITIES OF 10-15 PERCENT TODAY HAVE
RESULTED IN A SOLID CRITICAL FIRE WEATHER DAY FOR SE WY. AS
EXPECTED...LLVL GRADIENTS HAVE STRUGGLED OVR WRN NEBRASKA WHICH HAS
MITIGATED CRITICAL CONDITIONS THERE. THESE CONDITIONS WILL CONTINUE
INTO EARLY EVENING...BEFORE THE ATMOSPHERE DECOUPLES. OTHERWISE...A
DRY AND MOSTLY CLEAR NIGHT AHEAD.
VIRTUALLY A CARBON COPY DAY AHEAD FOR MONDAY...ALTHOUGH A WEAK FRONT
OVR PORTIONS OF THE ERN PLAINS WILL COMBINE WITH A BIT MORE CLOUD
COVER TO KEEP TEMPERATURES A FEW DEGREES COOLER THAN TODAY. BY
21Z...THIS BOUNDARY/INVERTED SFC TROF SHOULD BE LOCATED FROM LUSK TO
NR SIDNEY. GRADIENTS WILL CERTAINLY BE ENOUGH FOR ANOTHER CRITICAL
FIRE WEATHER DAY...THOUGH LOWER TEMPS WILL KEEP HUMIDITIES A BIT
MORE MARGINAL THAN TODAY. EVEN SO...CONFIDENCE IS GROWING THAT AREAS
AT LEAST EAST OF THE LARAMIE RANGE WILL APPROACH IF NOT REACH
CRITICAL THRESHOLDS AGAIN ON MONDAY.
CONVECTION POTENTIAL INCREASE FOR TUESDAY AFTERNOON AS MODELS HAVE
BEEN VERY PERSISTENT IN SETTING UP AN INSTABILITY AXIS IN THE
VICINITY OF LLVL CONVERGENCE AREA ALONG THE LEE SIDE PRESSURE
TROUGH. MAY EVEN SEE SOME ISOLATED THUNDER WITH PROGD SBCAPES OF 200-
300 J/KG. HAVE CONFINED THESE CONVECTIVE CHANCES FOR THE SOUTHEAST
WYOMING PLAINS AND NRN NEBRASKA PANHANDLE TUESDAY AFTERNOON AND
EVENING. WOULD EXPECT VERY LIMITED COVERAGE HOWEVER. TEMPS WILL BE A
FEW DEGREES COOLER ON TUESDAY WITH THICKER CLOUD COVER AND CAA AS
THE NEXT SYSTEM APPROACHES. MODELS ARE HINTING AT A DRIZZLE AND/OR
LOW STRATUS/FOG EVENT SETTING UP ACROSS THE ERN PLAINS LATE TUESDAY
NT WITH BL PROGS SATURATED ON BOTH MODELS. THIS WILL SET THE STAGE
FOR BETTER CONVECTIVE CHANCES ON WEDNESDAY.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 228 PM MDT SUN APR 5 2015
THE MAIN CONCERN WITH THIS FORECAST PACKAGE IS THE IMPACTS FROM
THE UPPER LEVEL TROF MOVING INTO THE PACIFIC NORTHWEST.
WEDNESDAY-WEDNESDAY NIGHT:
LATEST WATER VAPOR/VISIBLE SATELLITE LOOPS WERE SHOWING OPEN CELL
CLOUD FORMATIONS OVER THE PACIFIC. THE OPEN CELLS APPEAR TO BE
DEVELOPING ON THE BACK SIDE OF THE SURFACE LOW WHICH IS INDICATION
OF COLD AIR ADVECTION. 90KT UPPER LEVEL JETLET (ACCORDING TO GOES
HIGH DENSITY WINDS) ALSO APPEARS TO BE DIGGING ACROSS THIS AREA.
THIS SHOULD ALLOW THIS UPPER TROF TO AMPLIFY AND INTENSIFY DURING
THE NEXT 24HRS OR SO. THE MODELS ARE PROGGING THIS WAVE TO SHIFT
EAST THROUGH THE ROCKIES THROUGH WEDNESDAY. AHEAD OF THIS
WAVE...WE SHOULD SEE THE LEE SIDE TROF INTENSIFY WHICH SHOULD
ALLOW FOR THE LOW LEVEL FLOW IN THE PLAINS TO BECOME SOUTHEAST AND
BRING UP MOISTURE FROM THE GULF DURING THE COURSE OF THE DAY. MAY
SEE A FEW THUNDERSTORMS DEVELOP WEDNESDAY AFTERNOON ALONG THE LEE
SIDE TROF WHICH MAY CONTAIN SOME DRY LIGHTNING. WE STILL KEPT THE
BEST CHANCE OF THUNDERSTORMS IN THE PICTURE EAST OF THE LARAMIE
RANGE WEDNESDAY EVENING AND OVERNIGHT...ESPECIALLY IF AN INVERTED
SURFACE TROF DEVELOPS AND THE LOW LEVEL MOISTURE STAYS LOCKED IN
PLACE. SOME OF THE STORMS MAY BE STRONG WEDNESDAY EVENING ESPECIALLY
WITH AMPLE AMOUNT OF SHEAR/INSTABILITY IN PLACE.
THURSDAY-THURSDAY NIGHT:
THE 12Z GFS APPEARS TO BE MUCH MORE PROGRESSIVE WITH THE TRACK OF
THE UPPER LEVEL TROF COMPARED TO PREVIOUS RUNS. MEANWHILE...THE
12Z ECMWF SOLUTION/SEVERAL MEMBERS OF THE GEFS ARE TRACKING THE
UPPER TROF ACROSS CENTRAL COLORADO AND LIFTING NORTHEAST INTO
WESTERN NEBRASKA BY THURSDAY EVENING WHICH IS A LITTLE FURTHER
SOUTH COMPARED TO PREVIOUS RUNS. THESE SOLUTIONS SEEM BE MORE
PLAUSIBLE AT THIS TIME ESPECIALLY CONSIDERING THE GEM/UKMET
SOLUTIONS HAVE SHIFTED THE UPPER TROF A LITTLE FURTHER SOUTH
COMPARED THEIR PREVIOUS RUNS.
THE MAIN QUESTION DURING THIS TIMEFRAME WILL BE THE TIMING OF WHEN
THIS UPPER TROF WILL INTENSIFY AND WHETHER OR NOT THE SYSTEM WILL
BEGIN TO WRAP UP THE MOISTURE AND BRING STRONGER COLD AIR
ADVECTION. AT THIS POINT...THE MODELS ARE SUGGESTING LATE
WEDNESDAY NIGHT INTO THURSDAY WHICH MAKES SENSE WITH THE JETLET
KICKING OUT INTO THE PLAINS. THE BEST CHANCE OF SNOW WILL BE IN
THE HIGHER ELEVATIONS ABOVE 5000FT MAINLY IN WYOMING...BUT THE
BETTER CHANCES OF PRECIP ARE EXPECTED TO BE IN THE NEBRASKA
PANHANDLE WHERE IT MAY BE A MIX OF RAIN/SNOW. IN FACT...PRECIPITATION
AMOUNTS COULD BE UP TO ONE HALF INCH IN THIS AREA. STILL TOO EARLY
TO CALL ON WHETHER OR NOT WE WILL SEE SNOW ACCUMULATION...BUT IF
THE WRAP AROUND PRECIP BEGINS WEDNESDAY NIGHT IT WILL CERTAINLY
BE WORTH WATCHING. ANOTHER CONCERN WILL BE STRONG GUSTY NORTH
WINDS DEVELOPING BEHIND THIS SYSTEM WHICH MAY INCREASE THE IMPACTS
IN AREAS THAT RECEIVE SNOWFALL. THE RAIN/SNOW SHOULD BEGIN TO
DIMINISH FROM WEST TO EAST THURSDAY NIGHT AS THE SYSTEM BEGINS TO
DEPART THE AREA.
FRIDAY-SUNDAY:
HIGH PRESSURE WILL BUILD INTO THE AREA ON FRIDAY WHICH WILL ALLOW
FOR CLEARING SKIES FROM WEST TO EAST. MAY STILL HAVE TO CONTEND
WITH LIGHT SNOW IN THE PANHANDLE EARLY FRIDAY MORNING...BUT THIS
SHOULD END FAIRLY QUICKLY AS SURFACE HIGH PRESSURE NOSES ITS WAY
INTO THE AREA. TEMPERATURES MAY BE A BIT SLOW TO RECOVER IN AREAS
EAST OF THE LARAMIE RANGE...BUT SHOULD RECOVER FAIRLY WELL INTO
THE 40S AND 50S IN THE WEST. SATURDAY-SUNDAY DOWNSLOPE FLOW IS
EXPECTED TO COMMENCE OVER THE AREA IN RESPONSE TO A WEAK UPPER
LEVEL RIDGE. AS A RESULT...WARMER TEMPERATURES WILL RETURN ON
SATURDAY BEFORE THE NEXT TROF MOVES INTO THE PICTURE EITHER LATE
SUNDAY INTO MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1201 AM MDT MON APR 6 2015
PERSISTENT EAST-NORTHEAST WINDS UP NEAR KCDR THIS EVENING ARE
EXPECTED TO CONTINUE TONIGHT...WITH LATEST SREF AND HRRR GUIDANCE
SUGGESTING PERHAPS STRATUS DEVELOPING INTO THE NORTHERN PANHANDLE
AROUND SUNRISE MONDAY. CONFIDENCE IS MARGINAL IN THIS HAPPENING
DUE TO LACK OF STRATUS REPORTS IN UPSTREAM OBS AT TAF
ISSUANCE...BUT DID MENTION AT LEAST SCT MVFR CIGS AT KCDR AS THIS
PATTERN SEEMS FAVORABLE FOR AT LEAST PATCHY STRATUS DEVELOPMENT.
ELSEWHERE SHOULD REMAIN VFR THROUGH MUCH OF MONDAY. THE STRATUS
WILL LIKELY RETURN TO THE PANHANDLE AND PERHAPS THE PLAINS OF
SOUTHEAST WYOMING MONDAY NIGHT...WITH CIGS LOWERING FROM EAST TO
WEST MAINLY AFTER 03Z TUESDAY.
THE SFC TROUGH STILL LOOKS LIKE IT WILL MOVE WESTWARD ACROSS THE
PLAINS OVERNIGHT...STALLING FROM KDGW-KSNY. THIS BOUNDARY WILL
SHIFT ONLY SLIGHTLY EAST THROUGH MONDAY AFTERNOON...WITH EAST-
SOUTHEAST WINDS EXPECTED TO PREVAIL OVER THE PANHANDLE SITES AND
SOUTHWEST WINDS ACROSS WYOMING. GUSTS 25-40 KTS ARE POSSIBLE
ACROSS WYOMING...ESPECIALLY ALONG AND WEST OF THE LARAMIE
RANGE...WITH UP TO 20 KTS IN THE PANHANDLE. WINDS WILL STEADILY
DIMINISH WITH SUNSET.
&&
.FIRE WEATHER...
ISSUED AT 830 PM MDT SUN APR 5 2015
CRITICAL CONDITIONS WILL BE MORE MARGINAL ON MONDAY...WITH
TEMPERATURES 3-5F DEGREES COOLER. HOWEVER...WINDS WOULD DEFINITELY
SUPPORT ANOTHER CRITICAL DAY ESPECIALLY FOR LOCATIONS EAST OF THE
LARAMIE RANGE. IT LOOKS LIKE ANY THREAT OF CRITICAL CONDITIONS COME
TO AN END TUE-WED AS MOISTURE AND AFTERNOON SHOWER/THUNDERSTORM
CHANCES INCREASE. WIDESPREAD PRECIPITATION CHANCES EXIST WEDNESDAY
NIGHT AND THURSDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...RJM
SHORT TERM...CAH
LONG TERM...REC
AVIATION...RJM
FIRE WEATHER...CAH/RJM
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1123 PM MDT TUE APR 7 2015
.UPDATE...
ISSUED AT 830 PM MDT TUE APR 7 2015
ALLOWED THIS EVENINGS RED FLAG WARNING TO EXPIRE. IN ADDITION...
ADDED AREAS OF DENSE FOG TO SECTIONS OF THE FAR SOUTHEASTERN
COLORADO PLAINS FROM LATER TONIGHT INTO WEDNESDAY MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 251 PM MDT TUE APR 7 2015
...EXTREME FIRE WEATHER CONDITIONS ON WEDNESDAY...
RED FLAG CONDITIONS CURRENTLY BEING MET OVER MOST OF THE
CWA...EXCEPT NR THE KS BORDER OVER THE FAR SERN PLAINS...WHERE QUASI-
STATIONARY BOUNDARY IS HOLDING STEADY AND ERLY WINDS STILL
MAINTAINING DEW POINTS IN THE 20S-30S. WILL SEE GUSTY SW WINDS
CONTINUE OVER THE REST OF OUR AREA THROUGH EARLY EVE. THE ERLY PUSH
SHOULD ADVANCE INTO CROWLEY AND OTERO COUNTIES TONIGHT...POSSIBLY
MAKING A RUN TOWARDS KPUB...BUT LOW CLOUDS WILL PROBABLY BE CONFINED
TO THE FAR NERN COUNTIES.
STILL LOOKS LIKE TOMORROW WILL SEE THE WORST OF THE CRITICAL FIRE WX
CONDITIONS. MAY TAKE A WHILE FOR ERN COUNTIES TO MIX OUT DO TO THE
OVERNIGHT PUSH OF LOW LEVEL MOISTURE...BUT BY MID TO LATE AFTERNOON
SHOULD SEE RH FALL BELOW 10 PERCENT FOR MOST SPOTS...AND SW WINDS
GUSTING IN THE 30-40 KT RANGE. THE WORST CONDITIONS LOOK TO BE ALONG
AND NR THE I-25 CORRIDOR FROM KPUB AND SOUTHWARD...BUT IT WILL NOT
BE MUCH BETTER ELSEWHERE. NEEDLESS TO SAY...WILL HAVE TO BE EXTREMELY
CAUTIOUS TOMORROW TO AVOID FIRE STARTS SINCE ANY FIRE COULD QUICKLY
GET OUT OF CONTROL.
TEMPS ALOFT WILL BE ON THE COOL SIDE THROUGH TOMORROW...SO DESPITE
THE STRONG WRLY FLOW SHOULD SEE TEMPS GENERALLY REMAIN IN THE 60S TO
AROUND 70 OVER THE I-25 CORRIDOR...AND IN THE 70S FOR THE ERN PLAINS
TOMORROW. NO PRECIP IS EXPECTED UNTIL TOMORROW AFTERNOON...THEN
SHOULD SEE SOME LIGHT SHSN DEVELOP OVER THE CONTDVD. ANY ACCUMS
TOMORROW WILL GENERALLY BE LIGHT AND CONFINED TO THE HIGHER PEAKS
ALONG THE DVD. HAVE CUT BACK POPS A BIT MORE FOR THE REST OF OUR AREA
TOMORROW...AS MOST GUIDANCE KEEPS THE PRECIP N OF OUR AREA WITH THE
H5 CENTER RIDING EWD ALONG THE CO-WY BORDER. ROSE
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 251 PM MDT TUE APR 7 2015
AN UPR TROF WL BE MOVING ACRS THE AREA WED NIGHT...WITH WEST TO NW
SFC WINDS ACRS THE AREA. IT LOOKS WINDY MANY AREAS IN THE EVENING
AND JUST BREEZY THE REST OF THE NIGHT. THE FORECAST MODELS SHOW THE
POTENTIAL FOR SOME SHOWERS OVER THE CENTRAL MTNS IN THE EVENING
HRS...WITH DRY CONDITIONS ELSEWHERE. THE UPR TROF WL EXIT THE AREA
THU MORNING...WITH BREEZY NORTH WINDS ACRS THE ERN PLAINS BEHIND THE
TROF. THE WX LOOKS DRY IN THE MORNING BUT THERE COULD BE SOME ISOLD
PCPN OVR SOME OF THE MTN AREAS IN THE AFTERNOON AND EARLY EVENING
HOURS...ESPECIALLY OVR THE PIKES PEAK AREA AND THE CENTRAL MTNS.
ALTHOUGH THERE WL BE SOME BREEZY CONDITIONS OVR THE FAR ERN PLAINS
THU AFTERNOON...RH VALUES ARE EXPECTED TO BE TOO HIGH FOR FIRE WX
CONCERNS. TEMPS ON THU WL BE COOLER IN THE WAKE OF THE TROF...BUT
HIGH ARE FORECAST TO BE CLOSE TO AVERAGE.
ON FRI WESTERLY FLOW ALOFT WL BE OVR THE FORECAST AREA WITH AN UPR
TROF MOVING THRU THE NRN ROCKIES OF MTN AND WY. THE WX GENERALLY
LOOKS DRY ON FRI WITH HIGH TEMPS A LITTLE ABOVE AVERAGE. SATURDAY
THAT UPR TROF TO THE NORTH WL MOVE INTO THE DAKOTAS SENDING A FRONT
INTO THE ERN CO PLAINS. A WEAK DISTURBANCE IN THE FLOW WL MOVE ACRS
THE AREA SAT AND COULD BRING A FEW SHOWERS. THE GFS KEEPS THE BEST
MSTR AND PCPN TO THE EAST...WHILE THE ECMWF SHOWS PCPN CHANCES ACRS
MUCH OF THE AREA SAT AFTERNOON. FOR NOW WL JUST GO WITH SOME ISOLD
POPS OVR THE MTNS AND NR THE KS BORDER.
FOR SUN AN UPR TROF IS FORECAST TO MOVE INTO WRN CO AND WRN NM LATE
IN THE DAY. CONDITIONS ARE STILL GENERALLY DRY ACRS THE FORECAST
AREA...WITH THE POSSIBLE EXCEPTION OF SOME ISOLD TO SCT MTNS
SHOWERS. HIGH TEMPS SHOULD AGAIN BE ABOVE AVERAGE. SUN NIGHT AND
EARLY MON THAT TROF MOVES ACRS THE STATE...POSSIBLY BRINGING A FEW
SHOWERS TO THE AREA. AS THE TROF EXITS THE STATE TO THE EAST...SOME
BREEZY NORTHERLY WINDS CAN BE EXPECTED IN ITS WAKE...ALONG WITH SOME
SLIGHTLY COOLER TEMPS.
ON TUE AS A NEW UPR TROF MOVES INTO THE WRN STATE...BREEZY SWRLY
WINDS RETURN TO THE AREA ALONG WITH THE POTENTIAL FOR CRITICAL FIRE
WX CONDITIONS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1116 PM MDT TUE APR 7 2015
MOIST AIR MASS AND ACCOMPANYING IFR STRATUS AND FOG CONTINUE TO
BACK SOUTHWESTWARD ACROSS THE COLORADO PLAINS THIS EVENING...WITH
04Z HRRR NOW SUGGESTING BOUNDARY WILL PUSH ALL THE WAY WEST TO
KPUB AND KCOS OVERNIGHT BEFORE RETREATING EASTWARD QUICKLY DURING
THE DAY WED. UNSURE IF STRATUS DECK WILL MAKE IT AS FAR WEST AS
WIND SHIFT DOES...SO WILL KEEP BOTH KCOS AND KPUB TAFS VFR
OVERNIGHT AND THROUGH THE DAY WED...AND INTRODUCE ONLY SOME SCT
LOWER CLOUDS AT THIS POINT. IFR CONDITIONS WON`T BE TOO FAR AWAY
FROM KCOS BY 12Z...AND SUSPECT KFLY AND KMNH WILL SEE A PERIOD OF
LOWER CLOUDS IN THE MORNING. KALS WILL REMAIN VFR OVERNIGHT AND
THROUGH THE DAY WED. W-SW WINDS WILL INCREASE ALL TERMINALS BY
18Z...WITH GUSTS IN THE 30-40 KNOT RANGE WIDESPREAD DURING THE
AFTERNOON.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 8 PM MDT WEDNESDAY FOR COZ222-
224>237.
&&
$$
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
416 AM EDT WED APR 8 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL THROUGH FRIDAY. A COLD FRONT
WILL SHIFT THROUGH THE AREA FRIDAY NIGHT INTO SATURDAY...THEN STALL
SOUTH OF THE REGION ON SUNDAY BEFORE LIFTING BACK NORTH THROUGH THE
AREA AS A WARM FRONT ON MONDAY. ATLANTIC HIGH PRESSURE WILL THEN
PREVAIL THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
THROUGH SUNRISE...THE REMNANTS OF A SEVERE QLCS...WHICH MOVED
THROUGH THE SOUTH CAROLINA MIDLANDS YESTERDAY EVENING...WILL
SLOWLY DISSIPATE ACROSS BERKELEY AND UPPER CHARLESTON COUNTIES
OVER THE NEXT FEW HOURS. THE CONVECTIVE OUTFLOW GENERATED BY THE
QLCS CAN BE SEEN ON KCLX RADAR REFLECTIVITY DATA DROPPING SLOWLY
SOUTH-SOUTHEAST AND COULD PROVIDE A FOCUS FOR ADDITIONAL ISOLATED
SHOWERS/TSTMS THROUGH 5 AM...MAINLY ACROSS THE CHARLESTON TRI-
COUNTY AREA EVEN AS THE PARENT CONVECTIVE STEADILY DIES OUT.
A RISK FOR SHALLOW GROUND FOG REMAINS...MAINLY ACROSS SOUTHEAST
GEORGIA WHERE SURFACE DEWPOINTS ARE RUNNING A BIT HIGHER. KCLX VAD
WIND PROFILE DATA SUGGEST MECHANICAL MIXING IS LIKELY OCCURRING
ATOP THE NOCTURNAL INVERSION WITH 1000 FT WINDS RUNNING ABOUT 30
KT. THIS WILL LIKELY PREVENT ANY FOG THAT DEVELOPS FROM BECOMING
TOO WIDESPREAD OR DENSE. WILL CONTINUE TO HIGHLIGHT PATCHY FOG
THROUGH 12Z.
TODAY...THE SURFACE AND UPPER AIR SYNOPTIC PATTERN IS VERY
REMINISCENT OF SUMMER WITH MEAN 500 HPA RIDING IN PLACE ACROSS
THE SOUTHEAST U.S. WITH THE AREA POSITIONED ALONG THE WESTERN
FLANKS OF ATLANTIC HIGH PRESSURE. CONVECTIVE DEBRIS CLOUDINESS
EARLY THIS MORNING WILL GIVE WAY TO INCREASING INSOLATION THROUGH
THE DAY...WHICH WILL EVENTUALLY YIELD A MODEST CUMULUS FIELD AHEAD
OF THE DEVELOPING SEA BREEZE.
THERE ARE NO APPARENT LOW-LEVEL TRIGGERS FOR CONVECTION TODAY
EXCEPT THE RESULTANT SEA BREEZE CIRCULATION...WHICH IN ITSELF
DOES NOT LOOK OVERLY STRONG...BUT CONVECTIVE OUTFLOWS ARE LIKELY
LURKING ACROSS INLAND AREAS BASED ON EARLIER REFLECTIVITY DATA.
THE 00Z MODELS ARE NOT OVERLY AGGRESSIVE WITH THE COVERAGE OF
SHOWERS/TSTMS DURING PEAK HEATING...WHICH SEEMS PLAUSIBLE WITH
WEAK DNVA NOTED IN THE WAKE OF SHORTWAVE ENERGY PASSING OFFSHORE
THIS MORNING. DESPITE WEAK SUBSIDENCE...MODIFIED RAP SOUNDINGS DO
SHOW MODEST INSTABILITY DEVELOPING THROUGH THE DAY AS TEMPERATURES
RISE WELL INTO THE 80S WITH DEWPOINTS HOLDING IN THE LOWER-MID
60S. SUSPECT ISOLATED CONVECTION WILL INITIATE EITHER ALONG THE
SEA BREEZE ITSELF OR MORE LIKELY ALONG THE LAKE BREEZE OR RESIDUAL
CONVECTIVE OUTFLOW OVER INLAND AREAS BY EARLY-MID AFTERNOON WITH
ADDITIONAL CONVECTIVE CLUSTERS DEVELOPING ALONG MESOSCALE BOUNDARY
COLLISIONS...MAINLY INLAND AHEAD OF THE SEA BREEZE. POPS OF 20-30
PERCENT WILL BE MAINTAINED FOR LAND AREAS TODAY AND WITH TIMING
AND PLACEMENT OF THE HIGHEST GRIDDED POPS BLENDED HEAVILY TOWARDS
THE LATEST 4KM NSSL WRF. HIGHS WILL WARM INTO THE MID-UPPER 80S
AWAY FROM THE BEACHES.
AN ISOLATED STRONG OR SEVERE TSTM CAN NOT BE RULED OUT WITHIN A
MODERATELY UNSTABLE ENVIRONMENT (SBCAPE 2600 J/KG...LIFTED INDEX
-6C...SHOWALTER INDEX -2C...HCAPE ~900 J/KG WITH DCAPE 1200 J/KG
PER MODIFIED KOGB RAP SOUNDING)...ESPECIALLY WHERE UPDRAFTS BECOME
ENHANCED ALONG MESOSCALE BOUNDARY COLLISIONS. WBZ HEIGHTS REMAIN
FAIRLY LOW FOR THE TIME YEAR AND 0-6KM BULK SHEAR IS FORECAST TO
REMAIN 20-25 KT...WHICH IS JUST HIGH ENOUGH TO SUPPORT SOME
LOOSELY ORGANIZED MULTICELLULAR CLUSTERS. WILL HIGHLIGHT ISOLATED
STRONG TO SEVERE TSTMS IN THE HAZARDOUS WEATHER OUTLOOK.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
TONIGHT...EARLY EVENING CONVECTION WILL DISSIPATE WELL INLAND WITH
THE LOSS OF INSOLATION. WARM AND HUMID CONDITIONS WILL LINGER WITH
LOWS FALLING INTO THE LOWER-MID 60S. COULD SEE ANOTHER AROUND OF
PATCHY GROUND FOG IN SOME LOCATIONS...ESPECIALLY THAT RECEIVES
RAINFALL THIS AFTERNOON...BUT THE FOG DOES NOT LOOK SIGNIFICANT
ATTM.
THURSDAY...THE AREA WILL REMAIN ALONG THE WESTERN EDGE OF ATLANTIC
HIGH PRESSURE AND UNDER A MID LVL RIDGE OF HIGH PRESSURE EXTENDING
NORTHWARD FROM THE GULF OF MEXICO. THE BULK OF PRECIP ACTIVITY
SHOULD SHIFT SLIGHTLY MORE INLAND THAN PREVIOUS DAYS AS THE MID LVL
RIDGE EXPANDS OVER THE AREA WELL AHEAD OF A LOW PRESSURE TROUGH
DIGGING OVER THE CENTRAL UNITED STATES. THE PATTERN WILL RESULT IN
WARM TEMPS...WITH HIGHS IN THE MID TO UPPER 80S OVER MOST LOCATIONS.
TEMPS WILL REMAIN COOLER ALONG THE COAST GIVEN AN ONSHORE FLOW.
SUFFICIENT HEATING AND MOISTURE WILL SUPPORT A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS AWAY FROM THE COAST...BUT ACTIVITY WILL
LIKELY BE DRIVEN BY AN AFTERNOON SEABREEZE GIVEN THE LACK OF LARGER
SCALE FORCING. EXPECT MOST PRECIP TO DIMINISH WITHIN A FEW HOURS OF
SUNSET. OVERNIGHT LOWS SHOULD RANGE IN THE MID 60S. WE COULD SEE
SOME PATCHY FOG DEVELOP LATE WHILE WINDS ARE LIGHT/CALM AND DEWPTS
REMAIN IN THE MID 60S.
FRIDAY...ANOTHER WARM DAY IS ANTICIPATED WELL AHEAD OF COLD FRONT
THAT WILL MAKE WAY TO THE REGION LATE. EXPECT HIGH TEMPS TO WARM IN
THE MID/UPPER 80S FOR MOST LOCATIONS...EVEN AS CLOUD COVER INCREASES
FROM THE WEST. CHANCES OF SHOWERS AND/OR THUNDERSTORMS WILL BE
POSSIBLE...ESPECIALLY LATE AS MOISTURE DEEPENS AND MID LVL FORCING
BEGINS TO INCREASE ALONG AND AHEAD OF A SFC COLD FRONT MAKING WAY
INTO THE AREA FRIDAY NIGHT. AT THIS TIME...THE THREAT OF SEVERE
WEATHER REMAINS LOW GIVEN THE TIMING OF FROPA DURING THE OVERNIGHT
PERIOD. HOWEVER...THERE IS A LOW CHANCE OF A FEW STRONGER
THUNDERSTORMS GIVEN SBCAPES APPROACHING 1000-1250 J/KG AND 20-30 KT
LOW/MID LVL WIND FIELDS SHIFTING OVER THE AREA FRIDAY EVENING.
OVERNIGHT LOWS SHOULD REMAIN MILD UNTIL FROPA...IN THE MID 60S FOR
MOST LOCATIONS
SATURDAY...A COLD FRONT WILL PUSH THROUGH THE AREA EARLY WITH AT
LEAST CHANCES OF SHOWERS AND/OR THUNDERSTORMS AS FROPA OCCURS. DRYER
AND COOLER CONDITIONS WILL FOLLOW THE FRONT AS HIGH PRESSURE BUILDS
IN FROM THE NORTH. OVERALL HIGH TEMPS SHOULD PEAK NEAR 80 FOR
LOCATIONS AWAY FROM THE COAST...BUT WILL LIKELY BE ON A COOLING
TREND BY MID AFTERNOON OVER NORTHERN AREAS WHERE SFC WINDS SHIFT TO
NORTHEAST BEHIND THE FRONT. BY SATURDAY EVENING...MOST PRECIP
ACTIVITY WILL LIKELY BE FOCUSED IN SOUTHEAST GEORGIA...WHERE THE
FRONT CONTINUES A SOUTHWARD SHIFT BEFORE STALLING WELL SOUTH OF THE
AREA.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
A WEAKENED/STALLED FRONT WILL BE POSITIONED SOUTH OF THE AREA
THROUGH SUNDAY...WHILE A WEDGE OF HIGH PRESSURE BUILDS FROM THE
NORTH. TEMPS WILL BE COOLER...WITH OVERALL HIGHS IN THE MID 70S OVER
MOST LOCATIONS. A SLIGHT CHANCE TO CHANCE OF SHOWERS AND/OR
THUNDERSTORMS WILL MAINLY BE CONFINED TO LOCATIONS SOUTH OF
INTERSTATE 16 IN SOUTHEAST GEORGIA THROUGH EARLY MONDAY. CHANCES OF
SHOWERS AND THUNDERSTORMS SHOULD RETURN TO MOST AREAS ON MONDAY AS
THE STALLED FRONT LIFTS BACK NORTH AS A WARM FRONT WELL AHEAD OF A
DEEPENING LOW PRESSURE SYSTEM OVER THE CENTRAL UNITED STATES. HIGH
TEMPS SHOULD THEN RETURN INTO THE 80S THROUGH THE MIDDLE OF NEXT
WEEK AS THE AREA REMAINS SITUATED ALONG THE WESTERN EDGE OF ATLANTIC
HIGH PRESSURE AND STRONG RIDGING ALOFT.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
KCHS...TSTMS EAST OF KOGB ARE POISED TO REMAIN NORTH OF THE KCHS
TERMINAL...BUT WATCHING FOR POSSIBLE REDEVELOPING ALONG THE
SOUTHWARD FLANKING CONVECTIVE OUTFLOW BOUNDARY THAT IS APPROACHING
KMKS-KDYB. OTHERWISE VFR. SMALL CHANCE FOR SHALLOW GROUND FOG TO
IMPACT THE TERMINAL RIGHT AT SUNRISE...BUT IMPACTS LOOK MINIMAL AT
BEST. SEA BREEZE WILL PASS ROUGHLY 18Z WITH A BRIEF PERIOD OF
ELEVATED WINDS. BEST TSTM CHANCES THIS AFTERNOON WILL REMAIN WEST
OF THE TERMINAL.
KSAV...WATCHING FOR SHALLOW GROUND FOG DEVELOPMENT OVER THE NEXT
FEW HOURS. DEWPOINTS REMAIN ELEVATED...BUT THERE MAY BE JUST
ENOUGH MIXING ATOP THE BOUNDARY LAYER TO PREVENT WIDESPREAD FOG.
SHORT TERM GUIDANCE HAS BACK OFF CONSIDERABLY ON THE FOG POTENTIAL
AND THE 06Z TAF WILL REFLECT THIS. WILL HIGHLIGHT 4SM MIFG SCT004
BEGINNING AT 09-13Z WITH A TEMPO GROUP JUST BEFORE SUNRISE OF 2SM
MIFG. WILL NOT MENTION PREVAILING IFR ATTM. OTHERWISE VFR. SEA
BREEZE WILL PASS THE TERMINAL ROUGHLY 19Z WITH A BRIEF PERIOD OF
ELEVATED WINDS. BEST TSTMS CHANCES THIS AFTERNOON WILL REMAIN WEST
OF THE TERMINAL.
EXTENDED AVIATION OUTLOOK...LOW CHANCES OF FLIGHT RESTRICTIONS
THURSDAY AND FRIDAY WITH AFTERNOON SHOWERS AND/OR THUNDERSTORMS.
FLIGHT RESTRICTION CHANCES INCREASE FRIDAY NIGHT INTO SATURDAY
SATURDAY AS A COLD FRONT PASSES OVER BOTH TERMINALS.
&&
.MARINE...
THROUGH TONIGHT...SOUTHERLY WIND REGIME WILL PERSIST. WINDS WILL
GENERALLY REMAIN 10 KT OR LESS WITH SEAS 2-4 FT.
THURSDAY THROUGH MONDAY...CONDITIONS WILL REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS THROUGH LATE WEEK ALONG THE WESTERN EDGE OF ATLANTIC
HIGH PRESSURE. IN GENERAL...A SOUTHERLY WIND WILL REMAIN AT OR BELOW
15 KTS OUTSIDE DAILY SHOWERS AND/OR THUNDERSTORMS. BRIEF SURGES AND
SLIGHT CHANGES IN WIND DIRECTION SHOULD OCCUR NEAR AFTERNOON
SEABREEZE CIRCULATIONS. SEAS WILL BE NO HIGHER THAN 4 FT. WINDS/SEAS
SHOULD THEN INCREASE/BUILD THIS WEEKEND AS A COLD FRONT APPROACHES
FROM THE NORTHWEST FRIDAY...THEN SHIFTS OVER THE COASTAL WATERS
FRIDAY NIGHT INTO EARLY SATURDAY. HOWEVER...CONDITIONS ARE EXPECTED
TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS OUTSIDE THUNDERSTORM
ACTIVITY. A FEW THUNDERSTORMS COULD BE STRONG DURING FROPA FRIDAY
NIGHT. WINDS WILL SHIFT TO NORTH/NORTHEAST BEHIND THE FRONT AS IT
STALLS SOUTH OF THE COASTAL WATERS SATURDAY NIGHT AND SUNDAY. THE
STALLED FRONT IS THEN EXPECTED TO LIFT BACK NORTH AS A WARM FRONT ON
MONDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/DPB
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1222 AM EDT WED APR 8 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL THROUGH FRIDAY. A COLD FRONT
COULD APPROACH FROM THE NORTHWEST ON SATURDAY OR SUNDAY. A STRONGER
COLD FRONT COULD APPROACH THE SOUTHEAST BY TUESDAY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MESOSCALE UPDATE...QLCS CONTINUE TO MARCH EAST EARLY THIS MORNING
WITH RECENT KCLX RADAR TRENDS SUGGESTING SOME SOUTHERN DEVELOPMENT
ALONG THE EMERGING OUTFLOW. SOME OF THIS ACTIVITY IS POISED TO
IMPACT THE CHARLESTON TRI-COUNTY AREA...ESPECIALLY BERKELEY
COUNTY...OVER THE NEXT FEW HOURS. HAVE ADJUSTED POPS ACCORDINGLY
BY RAISING GRIDDED POPS IN THE LIKELY CATEGORY FOR NORTHERN
BERKELEY. 08/06Z RAP SOUNDING AT SAINT STEPHEN WAS NOT OVERLY
UNSTABLE...BUT THE APPROACHING QLCS APPEARS TO HAVE A WELL-
DEFINED COLD POOL THAT IS HELPING TO DRIVE THE STORMS EAST AND
SOUTHEAST. SO AN ISOLATED SEVERE TSTM CAN NOT BE RULED OUT. THE
STORMS DO APPEAR TO HAVE GUSTED OUT...OR AT LEAST IN THE PROCESS
OF GUSTING OUT...SO ITS UNCLEAR IF THIS ACTIVITY WILL REACH THE
CHARLESTON COUNTY COAST. CONVECTIVE TRENDS ARE BEING MONITORED.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/...
WEDNESDAY AND THURSDAY WILL BE ALMOST SUMMERLIKE AS THE LOW LEVELS
ARE DOMINATED BY HIGH PRESSURE STRETCHING FROM BERMUDA ACROSS THE
WESTERN ATLANTIC TO THE SOUTHEAST COAST...WHILE AN UPPER RIDGE SETS
UP SHOP OVER THE SOUTHEAST. 925 MB TEMPS OF NEAR 20C OVER THE
INTERIOR EACH DAY WILL MIX DOWN SO MAX TEMPS WILL REACH WELL INTO
THE 80S...WITH THE USUAL 10 OR MORE DEGREES COOLER AT THE BEACHES
DUE TO AFTERNOON ONSHORE FLOW. THE MAIN FOCUS FOR ANY SHOWERS OR
THUNDERSTORMS WILL BE THE SEA BREEZE BOUNDARY AS IT MOVES INLAND
DURING THE AFTERNOON...BUT THE LACK OF A SYNOPTIC SCALE FORCING
MECHANISM...ALONG WITH MIDDLING LAPSE RATES FROM 700-500
MB...SUGGEST THE ACTIVITY WILL ONLY SCATTERED IN NATURE. AFTER ANY
INLAND EVENING CONVECTION DIES OFF...TEMPS WILL ONLY DROP DOWN TO
THE 60S.
I THINK THERE WILL ALSO BE SOME PATCHY FOG AROUND EARLY THURSDAY
MORNING AS THE PRESSURE GRADIENT RELAXES AND DEWPOINTS REACH
CLIMATOLOGICALLY FAVORABLE LEVELS.
ON FRIDAY...A COLD FRONT WILL APPROACH FROM THE NORTHWEST DURING THE
DAY. THE CWA SHOULD STAY ON THE WARM SIDE OF THE FRONT DURING THE
DAY...BUT AN INCREASE IN CLOUD COVER SHOULD KEEP MAX TEMPS A COUPLE
OF DEGREES COOLER THAN THURSDAY AFTERNOON. ADDITIONALLY...AS HEIGHTS
BEGIN TO FALL ALOFT AND A MODEST JET NOSES IN FROM THE WEST...THERE
WILL BE A LITTLE BETTER CHANCE FOR AFTERNOON CONVECTION. CURRENT
POPS MAY CURRENTLY A LITTLE LOW...BUT THERE IS STILL SOME QUESTIONS
ABOUT THE TIMING OF THE FRONT...SO I DID NOT WANT TO JUMP TOO HIGH
THIS FAR IN ADVANCE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A COLD FRONT WILL APPROACH FROM THE WEST/NORTHWEST BEFORE STALLING
OVER OR NEAR THE AREA THIS WEEKEND...BRINGING AN INCREASE IN SHOWER
AND THUNDERSTORM ACTIVITY TO THE AREA. THE STALLED BOUNDARY SHOULD
TAKE ON A MORE EAST/WEST ORIENTATION SATURDAY AND SUNDAY...WHILE A
WEDGE OF HIGH PRESSURE TRIES TO SET UP OVER THE MID ATLANTIC
STATES...PERHAPS REACHING THE TRI-COUNTY AREA INTO EARLY NEXT WEEK.
THE POSITION OF THE STALLED BOUNDARY AND THE WEDGE OF HIGH PRESSURE
WILL HAVE A LARGE IMPACT ON THE THERMAL GRADIENT OVER THE
AREA...WITH TEMPS REACHING THE LOW 70S IN NORTHERN AREAS TO AROUND
80 ON SUNDAY. THE STALLED BOUNDARY SHOULD THEN LIFT NORTH ON MONDAY
AHEAD OF ANOTHER LARGE AND STRONGER TROUGH OF LOW PRESSURE DIGGING
OVER THE CENTRAL UNITED STATES. HIGH TEMPS SHOULD ONCE AGAIN WARM
INTO THE LOWER 80S OVER MOST AREAS BEFORE A STRONGER COLD FRONT
SWEEPS THROUGH THE AREA WITH SHOWERS AND/OR THUNDERSTORMS.
&&
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
WILL CONTINUE TO ASSESS PROGRESS OF A THUNDERSTORM COMPLEX
ADVANCING E/SE THROUGH THE MIDLANDS. THUNDERSTORMS ARE STILL
EXPECTED TO REMAIN NORTH OF THE REGION...BUT THERE IS A LOW
PROBABILITY FOR SHOWERS/THUNDERSTORMS TO DEVELOP INTO THE I-26
CORRIDOR...PERHAPS IMPACTING KCHS AFTER 06Z. WILL AMEND FORECASTS
AS NEEDED.
OTHERWISE...VFR THIS EVENING. FLIGHT RESTRICTIONS IN FOG ARE
LIKELY OVERNIGHT INTO EARLY WEDNESDAY...MOST LIKELY MVFR WITH A
CHANCE FOR IFR OR LOWER AT KCHS AND OCCASIONALLY IFR WITH A CHANCE
FOR LIFR AT KSAV.
EXTENDED AVIATION OUTLOOK...FOG COULD AGAIN PRODUCE FLIGHT
RESTRICTIONS LATE WEDNESDAY NIGHT INTO EARLY THURSDAY. SLIGHT
CHANCE FOR FLIGHT RESTRICTIONS DUE TO CONVECTION THURSDAY...WITH
MOST ACTIVITY OCCURRING INLAND OF THE TERMINALS. THE CHANCES
INCREASE A LITTLE FRIDAY AFTERNOON WITH BETTER CONVECTIVE COVERAGE
EXPECTED...BUT THE DURATION SHOULD NOT BE LONG.
THE OTHER POTENTIAL PROBLEM IS PATCHY GROUND FOG AT THE TERMINALS.
THIS SEEMS MOST LIKELY THURSDAY MORNING...AND POSSIBLY FRIDAY
MORNING IF THE APPROACHING COLD FRONT IS A LITTLE SLOWER...BUT
CHANCES ARE NOT MUCH BETTER THAN AVERAGE AT THIS POINT.
&&
.MARINE...
OVERNIGHT...A WEAK PRESSURE PATTERN WILL TRANSLATE TO S/SE WINDS
VEERING TO S/SW AT 10 KT OR LESS. SEAS 2-3 FT WITHIN 20 NM AND
3-4 FT BEYOND WILL BE DOMINATED BY AN 8-10 SECOND EASTERLY SWELL.
WEDNESDAY THROUGH FRIDAY...WITH HIGH PRESSURE DOMINATING THE WESTERN
ATLANTIC...WINDS WILL BE GENERALLY OUT OF THE SOUTH TO SOUTHWEST
THROUGH THE PERIOD...WITH DIRECTION BACKING TO ONSHORE DURING THE
AFTERNOONS. SPEEDS WILL BE 15 KNOTS OR LESS WITH SEAS 3 FEET OR
LESS...ALTHOUGH THEY MAY APPROACH 4 FEET BEYOND 40 NM NEAR THE GULF
STREAM AT NIGHT.
SATURDAY AND SUNDAY...WINDS/SEAS SHOULD THEN INCREASE/BUILD THIS
WEEKEND AS A COLD FRONT APPROACHES FROM THE WEST AND STALLS OVER OR
NEAR THE AREA...BUT EXPECT CONDITIONS TO REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS INTO EARLY NEXT WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
347 AM CDT WED APR 8 2015
.SHORT TERM...
347 AM CDT
THROUGH THURSDAY...
TODAY THROUGH FRIDAY NIGHT...
MAIN FOCUS IS ON PERIODS OF CONVECTION...PARTICULARLY THIS
MORNING ACROSS PART OF THE FORECAST AREAS...AND ACROSS THE ENTIRE
AREA TONIGHT INTO THURSDAY. SEVERE WEATHER THREAT REMAINS OF GREAT
CONCERN THURSDAY AFTERNOON AND EVENING.
EARLY MORNING SURFACE ANALYSIS DEPICTS LOW PRESSURE OVER
NORTHEASTERN MISSOURI...WITH AN INVERTED TROUGH EXTENDING
NORTHEAST ACROSS SOUTHEAST WI/LAKE MICHIGAN. THESE FEATURES APPEAR
TO BE ASSOCIATED WITH A COUPLE OF MID-LEVEL SHORT WAVE TROUGHS
PROPAGATING ACROSS THE REGION IN BROAD WEST-SOUTHWESTERLY FLOW
ALOFT. A CLUSTER OF THUNDERSTORMS HAD DEVELOPED ACROSS SOUTHEAST
IOWA LAST EVENING IN LOW LEVEL WARM/MOIST ADVECTION MAXIMA
NORTHEAST OF THE SURFACE LOW...AND CONTINUE TO PERSIST AND EXPAND
SLOWLY EASTWARD ACROSS PARTS OF ILLINOIS EARLY THIS MORNING ON 30
KT 925 MB JET AHEAD OF SHORT WAVE. THESE STORMS ARE LIKELY TO
CONTINUE TO DEVELOP EASTWARD ACROSS MAINLY THE SOUTHERN TWO THIRDS
OR SO OF THE CWA EARLY THIS MORNING AS THE SURFACE WAVE MOVE
THROUGH THE AREA. SPC MESOANALYSIS DATA INDICATES UPSTREAM AIR
MASS CHARACTERIZED BY STEEP MID-LEVEL LAPSE RATES IN EXCESS OF 7.5
C/KM YIELDING 1000-1500 J/KG OF ELEVATED MUCAPE...AND ROUGHLY
40-45 KT OF EFFECTIVE DEEP LAYER BULK SHEAR. SOME OF THE STRONGER
CORES MAY BE CAPABLE OF PRODUCING SOME MARGINAL HAIL THIS
MORNING...THOUGH AN OVERALL WEAKENING TREND IS EXPECTED AS THE LOW
LEVEL FLOW VEERS MORE WESTERLY AND DECREASES AND REDUCES LOW LEVEL
MOISTURE TRANSPORT/THETA-E ADVECTION ACROSS OUR SOUTH AND
SOUTHEAST COUNTIES. THIS TREND IS SUPPORTED BY HIGH-RES HRRR/RAP
GUIDANCE WHICH INDICATE ACTIVITY MOVING ACROSS THE AREA THROUGH
13-14Z.
MOIST/SATURATED LOW LEVEL AIR MASS HAS ALSO REDUCED VISIBILITY IN
FOG OVER THE PAST SEVERAL HOURS...WITH SOME PATCHES OF DENSE FOG
NOTED. MAY HAVE TO CONSIDER A HEADLINE...THOUGH MORNING SHOWERS
MAY HELP RAISE VISIBILITY SOMEWHAT AND WILL CONTINUE TO MONITOR.
NOT MUCH IS EXPECTED IN THE WAY OF ORGANIZED PRECIP FROM MID-
MORNING INTO THIS AFTERNOON...WITH PASSAGE OF THE SHORT WAVE AND
WEAKENING OF THE SURFACE WAVE ALONG THE FRONT TO OUR SOUTH. WEAK
BUT PERSISTENT SOUTHWEST FLOW WILL CONTINUE ABOVE THE SHALLOW COOL
BOUNDARY LAYER NORTH OF THE SURFACE FRONT...WHICH COULD PRODUCE
SOME LIGHT SHOWERS OR DRIZZLE AT ABOUT ANY TIME...BUT IT APPEARS
THAT THE NEXT ORGANIZED ROUND OF PRECIPITATION WILL HOLD OFF UNTIL
LATER THIS AFTERNOON AND MORE SO THIS EVENING AS ANOTHER SHORT
WAVE EJECTS AHEAD OF ADVANCING WEST COAST UPPER TROUGH.
THUNDERSTORMS CHANCES INCREASE MARKEDLY THIS EVENING AS THIS NEXT
WAVE APPROACHES THIS EVENING. SOME OF THESE ELEVATED STORMS
TONIGHT MAY ALSO HAVE THE CAPABILITY OF PRODUCING LARGE HAIL WITH
STEEP LAPSE RATES AND STRONG DEEP SHEAR.
SHOWERS AND THUNDERSTORMS WILL VERY LIKELY BE ONGOING ACROSS THE
FORECAST AREA EARLY THURSDAY MORNING...AND THE EFFECT OF THE
RESULTING COLD POOL AND CLOUDINESS WILL LIKELY COMPLICATE THE
EVOLUTION OF AFTERNOON POTENTIALLY SEVERE CONVECTION ACROSS THE
AREA. NONETHELESS...A STRONG AND VERY DYNAMIC SHORT WAVE WILL
EMANATE FROM THE CURRENT WEST COAST TROUGH RESULTING IN A
DEEPENING SURFACE LOW LIFTING NORTHEAST INTO FAR NORTHERN ILLINOIS
OR SOUTHERN WISCONSIN BY THURSDAY EVENING. THE COMBINATION OF THE
APPROACHING VIGOROUS SHORT WAVE AND DEEPENING SURFACE LOW WILL
LIFT THE CURRENT STATIONARY FRONT NORTHWARD ACROSS THE FORECAST
AREA AS A WARM FRONT...WITH THE WARM SECTOR SOUTH OF THE FRONT
EXPECTED TO BECOME MODERATELY UNSTABLE DURING THE AFTERNOON AS
MLCAPES INCREASE TO 1500-2500 J/KG. STRONG WEST-SOUTHWEST FLOW
ALOFT AND BACKED SOUTHERLY WINDS IN LOW LEVELS AHEAD OF THE LOW
WILL SUPPLY COPIOUS SHEAR... SUPPORTIVE OF ORGANIZED SEVERE
THUNDERSTORMS DEVELOPING DURING THE AFTERNOON AND EARLY EVENING
HOURS AHEAD OF THE COLD FRONT WHICH WILL PUSH ACROSS THE CWA BY
MIDNIGHT. SPC HAS MAINTAINED A LARGE ENHANCED SEVERE RISK ACROSS
THE AREA FOR DAY 2/THURSDAY...WITH SOME UNCERTAINTY REMAINING
PRIMARILY TO THE EFFECT OF MORNING CONVECTION ON MESOSCALE SURFACE
FEATURES BY THURSDAY AFTERNOON. IF THE DYNAMIC SYSTEM IS ABLE TO
OVERCOME STABILIZING INFLUENCE OF EARLIER STORMS...AND IT LIKELY
WILL TO SOME DEGREE...THEN A SIGNIFICANT RISK OF DAMAGING
WIND...LARGE HAIL AND TORNADOES WILL EXIST.
WITH THE SURFACE LOW PASSING NEAR/NORTH OF THE AREA THURSDAY
NIGHT...THE COLD FRONT WILL SWEEP EAST DURING THE EVENING AND
BRING AN END TO THE SEVERE THREAT AS DRIER/COOLER AIR SPREADS IN.
A STRONG NORTHERN STREAM SHORT WAVE IS PROGGED TO DIG ACROSS THE
UPPER MIDWEST BEHIND THE FIRST SYSTEM ON FRIDAY...THOUGH DRY
AIRMASS AND CAPPING INVERSION IN 700-600 MB LAYER NOTED IN
FORECAST SOUNDINGS SHOULD PRECLUDE PRECIP IN ANY ORGANIZED
FASHION.
TEMPS...SHARP CONTRAST CONTINUES TODAY-TONIGHT WITH EAST-
NORTHEAST FLOW NORTH OF THE STATIONARY FRONT AND MOIST/CLOUDY LOW
LEVEL AIR MASS. MAY VERY WELL SEE HIGHS TODAY RANGING FROM THE
MID-40S IN FAR NORTHEAST IL TO THE LOWER 70S ALONG THE LOT/ILX
BORDER. WITH FRONT LIFTING NORTH THURSDAY MUCH OF THE AREA MAY BE
IN THE 70S...THOUGH AGAIN MORNING CONVECTION AND RESIDUAL OUTFLOW
OR CLOUDS COULD AFFECT MAX TEMPS. COOLER BUT NEAR NORMAL FRIDAY
BEHIND THE COLD FRONT...BUT STILL 55-60.
RATZER
&&
.LONG TERM...
142 AM CDT
SATURDAY THROUGH TUESDAY...
THE FIRST FEW PERIODS OF THE EXTENDED LOOK TO BE RELATIVELY
BENIGN FOR THE GREAT LAKES REGION...WITH ENSEMBLES DEMONSTRATING
MINIMAL SPREAD IN THE 500MB WAVE PATTERN. WEAK TROUGHING WILL BE
PIVOTING EAST ACROSS THE MID-ATLANTIC REGION SAT...WITH DIFFLUENT
FLOW ARRIVING FOR THE WESTERN GREAT LAKES SAT. THE PATTERN QUICKLY
FLATTENS SUN...WITH PRECIP CHANCES RETURNING FOR THE SECOND HALF
OF THE WEEKEND INTO EARLY NEXT WEEK.
ENSEMBLES BEGIN TO POINT TOWARDS A TROUGH TRYING TO DIG INTO THE
WESTERN CONUS MON...WHICH COULD SUPPORT A SHORTWAVE DEVELOPING ALONG
THE LEE-SIDE OF THE ROCKIES. WITH THE WESTERN GULF OF MEXICO
OPEN...MOISTURE SHOULD EASILY LIFT NORTH TOWARDS THE OZARKS INTO IL
LATE MON INTO TUE. AS A RESULT INSTABILITY WILL LIKELY INCREASE...SO
WILL CONTINUE TO MENTION THUNDER MON/TUE OF NEXT WEEK.
WITH THE RELATIVELY ACTIVE FLOW...THE EXTENDED TEMPS MAY END UP
SLIGHTLY ABOVE SEASONAL OR MAINLY IN THE LOW/MID 60S. PRIOR TO THE
SHORTWAVE ARRIVAL MON...TEMPS MAY PUSH INTO THE UPR 60S OR NEAR 70.
OVERNIGHT LOWS WILL ALSO REMAIN MILD.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* IFR/LIFR THRU THE PERIOD.
* EASTERLY WINDS THRU THE PERIOD.
* CHANCE OF SHOWERS OVERNIGHT THRU MID MORNING...LOW CHANCE FOR
THUNDERSTORMS.
* SCATTERED THUNDERSTORMS LATE EVENING INTO THURSDAY MORNING. CMS
//DISCUSSION...UPDATED 06Z...
COMPLEX OF THUNDERSTORMS OVER SOUTHEAST IA WILL MOVE GENERALLY
EAST INTO WEST CENTRAL IL OVER THE NEXT FEW HOURS. SHORT TERM/HI
RES GUIDANCE CONTINUES TO SHOW THIS ACTIVITY REMAINING MAINLY
SOUTH OF THE TERMINALS AND SLOWLY WEAKENING TOWARD SUNRISE WITH
ADDITIONAL DEVELOPMENT POSSIBLE ACROSS EASTERN IL AND NORTHWEST
INDIANA...WITH SHOWERS OR POSSIBLE DRIZZLE FURTHER NORTH.
CONFIDENCE OF TSRA AT THE TERMINALS IS LOW ENOUGH TO REMOVE
MENTION OTHER THAN VICINITY AT GYY BUT TRENDS WILL NEED TO BE
MONITORED EARLY THIS MORNING.
SHOWER ACTIVITY COULD CONTINUE THRU THE DAY BUT GENERALLY SOUTH OF
THE TERMINALS SO HAVE MAINTAINED DRY CONDITIONS INTO EARLY THIS
EVENING. SHRA/TSRA ARE EXPECTED TO DEVELOP LATER THIS EVENING AND
CONTINUE...PERHAPS IN A COUPLE OF WAVES...THRU THURSDAY MORNING.
MEDIUM CONFIDENCE SO INCLUDED VICINITY MENTION BUT LOW CONFIDENCE
FOR TIMING/DURATION.
WINDS HAVE SHIFTED EAST/SOUTHEAST EARLY THIS MORNING AND SHOULD
GRADUALLY TURN BACK EASTERLY OVERNIGHT AND THEN NORTHEASTERLY
LATER THIS MORNING. SPEEDS ARE BIT UNCERTAIN AS GUIDANCE SUGGEST
SPEEDS COULD DIMINISH UNDER 10KTS BUT NOT CONFIDENT ENOUGH TO
LOWER PREVAILING SPEEDS JUST YET. WINDS WILL TURN BACK MORE EAST
OR SOUTHEAST LATER THIS EVENING AND OVERNIGHT...THEN LIKELY SHIFT
SOUTHERLY BY THURSDAY MORNING.
IFR/LIFR CIGS ARE EXPECTED TO CONTINUE THRU THE PERIOD...PERHAPS
LOWERING A BIT TOWARD SUNRISE WITH VISIBILITIES ALSO LOWERING. ITS
POSSIBLE CIGS MAY LIFT TO LOWER MVFR THIS AFTERNOON BUT CONFIDENCE
IS LOW. CMS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH FOR IFR/LIFR THRU THE PERIOD.
* MEDIUM FOR WINDS THRU THE PERIOD.
* MEDIUM FOR SHOWERS OVERNIGHT...LOW FOR INTENSITY/DURATION. LOW
FOR CHANCE OF THUNDERSTORMS TOWARD DAYBREAK.
* MEDIUM FOR THUNDERSTORMS TONIGHT...LOW ON TIMING/DURATION. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY...STRONG TSRA. MVFR. STRONG/GUSTY SOUTH/SOUTHWEST
WINDS.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...DRY/VFR. SOUTHEAST WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. MVFR POSSIBLE. SOUTH WINDS.
BEACHLER
&&
.MARINE...
340 PM CDT
A PERIOD OF ACTIVE WEATHER IS UNDERWAY FOR LAKE MICHIGAN. AS OF
TUESDAY AFTERNOON...A STATIONARY FRONTAL BOUNDARY LIES SOUTH OF THE
LAKE WHILE STRONG HIGH PRESSURE TRACKS ACROSS EASTERN ONTARIO INTO
QUEBEC. BETWEEN THE FRONTAL TROUGH TO THE SOUTH LAKE AND THE HIGH
TO THE NORTH...PERSISTENT NORTHEAST TO EAST WINDS OF 25 TO 30 KT
WILL COVER THE LAKE...WITH THE STRONGEST WINDS OVER THE NORTHERN
PORTIONS OF THE LAKE. DEWPOINTS HAVE BEEN INCREASING OVER THE
SOUTHERN PORTIONS OF THE LAKE...LEADING TO THE FORMATION OF DENSE
FOG...ESPECIALLY FOR THE SOUTHERN PORTIONS OF THE LAKE. LOW PRESSURE
DEVELOPING OVER THE WESTERN PLAINS WILL QUICKLY DEEPEN AND TRACK TO
NORTHERN WISCONSIN...FORCING THE STATIONARY FRONT NORTH AS A WARM
FRONT. WINDS WILL SHIFT FROM ELY-SELY TO SWLY FOLLOWING THE PASSAGE
OF THE WARM FRONT AND TEMPORARILY SUBSIDE...BUT A STRENGTHENING
GRADIENT AHEAD OF AN APPROACHING COLD FRONT WILL HELP STRENGTHEN
WINDS BACK TO 25 TO 30 KT. THE COLD FRONT TRAILING SOUTHWEST FROM
THE FAST-MOVING LOW WILL SWEEP ACROSS THE LAKE ON SATURDAY. HIGH
PRESSURE IS EXPECTED TO SPREAD ACROSS THE LAKE ON
SATURDAY...USHERING IN A PERIOD OF QUIETER WEATHER THAT SHOULD
PERSIST INTO EARLY NEXT WEEK.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 5 AM
THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
256 AM CDT Wed Apr 8 2015
.SHORT TERM...(Today)
ISSUED AT 255 AM CDT WED APR 8 2015
Latest surface analysis indicates the frontal boundary that was
holding stationary over south central Illinois has shifted further
north early this morning as a weak wave of low pressure was
approaching west central Illinois. Scattered convection has been
occurring north of the boundary over parts of east central Iowa
east into our far northern counties with some nickel hail reported
over the past hour around Lacon in Marshall county. We expect the
scattered convection to continue into the morning hours as the wave
rides east along the boundary. As the surface low shifts to our east
later this morning, there may actually be a southward push to the
front which is going to cause some significant problems with respect
to the afternoon temperatures, especially along and north of I-74.
The latest HRRR does indicate another weak wave forming to our west
along the boundary early this afternoon with another complex of
storms approaching west central IL. Not sure if this particular
complex of storms will ride along the boundary into central Illinois
or dive more southeast into the higher instability air mass south
of the front. POPs will increase again this afternoon in response to
this secondary wave approaching from the west. Severe potential
increases this afternoon thru this evening as the boundary gets
a push northward as the more significant shortwave pushes into the
Plains. With the warm front expected to edge across the area this
afternoon and evening, damaging wind gusts, large hail and isolated
tornadoes will all be possible. The tornado threat looks tied more
into areas along and just north of the warm front later this
afternoon and evening. Coolest temps north of I-74 where more of an
easterly flow will prevail, while south of the boundary, a blend of
the MET/MAV guid seems reasonable at this point.
&&
.LONG TERM...(Tonight through Tuesday)
ISSUED AT 255 AM CDT WED APR 8 2015
Severe weather threat through Thursday evening continues to dominate
the first part of the forecast. Current upper low moving into
northwest Nevada will open up but remain a fairly sharp wave as it
traverses the Plains on Thursday. This will help develop a surface
low over western Kansas this evening, which will surge northeast and
shove the frontal boundary back northward tonight. The trailing cold
front will sweep from west to east across the state Thursday evening
as a result.
Convection to our southwest expected to expand northeastward into
the mid-Mississippi Valley this evening. Latest SPC Day1 outlook
extended the slight risk across the entire CWA, with an enhanced
risk of severe storms from basically Springfield-Peoria westward.
This enhanced risk covers the entire area on Thursday, with
high-resolution models focusing on the mid-afternoon through early
evening time frame as the best potential in our area.
Short period of cooler and drier weather on tap for the first part
of the weekend, as high pressure drifts across the Midwest. However,
longer range models showing extended periods of rain chances early
next week. The GFS and ECMWF have a sizable range on the position
of a frontal boundary that will be setting up Sunday night and
Monday, both starting off roughly along I-70 but the GFS shows a
much stronger surge to the north by Tuesday. However, with both
favoring some sort of precip, have kept healthy rain chances in the
forecast for early next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1155 PM CDT TUE APR 7 2015
A stationary front extending across central IL, just north of
I-70, is forecast to drift slowly northward overnight, in response
to the approach of a weakening low pressure center across
Missouri. The surface low and associated 500mb shortwave will help
trigger showers and storms in central IL the rest of the night.
A complex of storms has already developed west of PIA in SE Iowa.
The track of those storms looks to be just NW of PIA airport.
However, the HRRR and NCEP 4km WRF show additional development is
expected to the SE of the current storms. The new storms should
affect PIA and BMI between 07z and 12z, with the southern extend
possibly affecting the other terminal sites during that time.
SPI/DEC/CMI sites have returned to MVFR cloud heights. PIA/BMI
have remained LIFR due to 200ft cigs. BMI with vis now at 1/2sm FG.
Clouds are forecast to remain status quo for much of the night,
with some improvement as storms/showers pass near the terminals.
The weakening low pressure is still progged to advance across
central IL through early morning, dissipating before it reaches
Indiana. That will keep storm chances going through around 12z.
Additional storms are forecast to arrive tomorrow evening, per the
4km WRF.
ESE winds of 10-15kt will continue at 8-12kt overnight, with wind
directions highly dependent on how far north the stationary front
drifts by morning. Winds tomorrow morning could become variable
under the front, and eventually prevail from the N for PIA and
southwest for BMI/SPI/DEC/CMI. The GFS and NAM have differing wind
solutions, but went closer to the NAM with this set of TAFs.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1249 AM CDT WED APR 8 2015
.UPDATE...
WE HAVE MADE SOME CHANGES TO CUT BACK ON POPS A BIT OVER THE AREA
TONIGHT. CONVECTIVE TRENDS THIS EVENING ASSOCIATED WITH THE UPPER
LEVEL DISTURBANCE SHIFTING EASTWARD OVER NORTHEASTERN IOWA HAS
LARGELY SUGGESTED THAT MOST OF THE ACTIVITY WILL REMAIN RIGHT
ALONG OR JUST NORTH OF THE ILLINOIS BOARDER IN SOUTHERN WISCONSIN.
AS SUCH...I HAVE CUT POPS DOWN...ESPECIALLY SOUTH OF I88.
THE 00 UTC SOUNDING OUT OF KILX INDICATES SOME STEEP MID-LEVEL LAPSE
RATES...BUT REMAINS CAPPED TO ELEVATED CONVECTION. THEREFORE...IN
THE SHORT TERM PERIOD...THROUGH AT LEAST 06 UTC...IT APPEARS
UNLIKELY THAT ANY ACTIVITY WILL DEVELOP SOUTH OF THE CURRENT
ACTIVITY. HOWEVER...SOME HIRES GUIDANCE SUGGESTS THAT SOME WIDELY
SCATTERED STORMS COULD DEVELOP ACROSS MY SOUTHERN CWA VERY LATE
TONIGHT IN CLOSER PROXIMATE TO THE SURFACE FRONTAL ZONE...IN
ASSOCIATION WITH SOME BETTER MOISTURE TRANSPORT ALONG THE LOW LEVEL
JET. CONFIDENCE IS NOT THE GREATEST THAT THIS WILL MATERIALIZE
HOWEVER...BUT IF ANY STORMS WERE TO DEVELOP...THE STEEP LAPSE RATES
COULD SUPPORT A SMALL HAIL THREAT. IT APPEARS THE BEST CHANCES FOR
THIS WILL BE AFTER 09 UTC THROUGH EARLY THURSDAY MORNING.
IT ALSO APPEARS THE MAIN THREAT FOR DENSE FOG MAY REMAIN IN CLOSER
PROXIMATE TO THE SURFACE FRONTAL ZONE TO OUR SOUTH...WHERE DEW
POINTS ARE INTO THE 50S. THEREFORE...WHILE THERE WILL LIKELY
CONTINUE TO BE FOG WITH 1 TO 3 SM VISIBILITIES OVER THE AREA...IT
APPEARS LESS LIKELY FOR DENSE FOG DEVELOPMENT OVERNIGHT OVER
FAR NORTHERN ILLINOIS.
KJB
&&
.SHORT TERM...
327 PM CDT
THROUGH WEDNESDAY NIGHT...
STRONG QUASI-STATIONARY FRONT IS DRAPED ACROSS CENTRAL ILLINOIS WITH
WARM AND HUMID AIR RESIDING SOUTH OF THIS BOUNDARY WITH 60 DEGREE
DEWPOINTS BUTTING UP AGAINST OUR SOUTHERN MOST CWA BORDER. TO THE
NORTH OF THE BOUNDARY YOU JUMP BACK A SEASON WITH BRISK NORTHEAST
WINDS AND CLOUDINESS HOLDING TEMPS IN THE 40S...EXCEPT NEAR THE LAKE
WHERE TEMPS ARE STILL IN THE UPPER 30S WITH SOME MARINE FOG. WEBCAMS
CONTINUE TO SUGGEST DENSEST FOG IS RIGHT AT THE SHORE...THOUGH STILL
EXPECT THAT THIS FOG COULD BEGIN TO OOZE INLAND WITH TIME TONIGHT
AND POSSIBLY INTO WEDNESDAY AS WELL. FRONTAL BOUNDARY WILL LIKELY
WAVER AROUND A BIT THROUGH WEDNESDAY NIGHT...POTENTIALLY CREEPING
NORTH INTO OUR SOUTHERN CWA AT TIMES WHICH WILL UNDOUBTEDLY CAUSE
HAVOC IN MAINTAINING HOURLY TEMPERATURE GRIDS AND PLACES A HIGHER
DEGREE THAN NORMAL OF UNCERTAINTY IN HIGH AND LOW TEMP FORECAST THE
NEXT 36 HOURS.
WATER VAPOR IMAGERY SHOWS A WELL DEFINED SHORTWAVE MOVING EASTWARD
INTO THE WESTERN CORNBELT THIS AFTERNOON WITH WAA IN ADVANCE OF THIS
FEATURE RESULTING IN AN INCREASE IN COVERAGE OF SHOWERS AND
THUNDERSTORMS ACROSS IOWA THIS AFTERNOON. GIVEN THE FARTHER
SOUTHWARD PLACEMENT OF THE FRONTAL BOUNDARY AND INSTABILITY AXIS I
SUSPECT THAT THIS ACTIVITY WILL HAVE A TENDENCY TO PROPAGATE/DEVELOP
SOUTHWARD WITH AN INCREASE IN COVERAGE AND INTENSITY THIS EVENING
WITH THE NOCTURNAL STRENGTHENING OF THE LOW LEVEL JET. PWATS OF
AROUND 200 PERCENT OF NORMAL SUGGEST THAT ANY THUNDERSTORMS THAT DO
DEVELOP COULD BE VERY EFFICIENT RAIN PRODUCERS. EXTRAPOLATION HAS
THAT SHORTWAVE MOVING EAST OF OUR AREA BY 06Z SUGGESTING MOST
ORGANIZED PRECIP SHOULD SHIFT EAST WITH IT THOUGH CONTINUED WAA
OVER TOP SHALLOW COLD AIR MASS DOES RAISE AT LEAST THE POTENTIAL OF
CONTINUED CONVECTIVE DEVELOPMENT INTO THE OVERNIGHT HOURS.
CANNOT RULE OUT SOME LINGERING MORE SHOWERS...MAINLY EASTERN
CWA...BUT OVERALL WEDNESDAY LOOKS TO BE DRY OTHER THAN SOME POSSIBLE
DRIZZLE WITH THE THICKER FOG NEAR THE LAKE. NEXT SHORTWAVE AND
ASSOCIATED RAMPING OF LOW LEVEL JET/WAA LOOKS TO BE WEDNESDAY NIGHT
WHEN ONCE AGAIN LOCALLY HEAVY RAINFALL WILL BE A DISTINCT
POSSIBILITY. ANTECEDENT CONDITIONS ARE GENERALLY PRETTY DRY...SO
OTHER THAN URBAN AREAS OR REMOTE THREAT OF EXTREME RAINFALL TOTALS
THINK THE FLASH FLOOD CONCERNS LOOK NOT TOO IMPRESSIVE AT THIS
TIME.
IZZI
&&
.LONG TERM...
327 PM CDT
THURSDAY NIGHT THROUGH TUESDAY...
PRIMARY TROUGH IS STILL PROGGED TO MOVE QUICKLY EASTWARD AND INTO
THE MIDWEST BY THURSDAY AFTERNOON. GUIDANCE VARIES SOME WITH RESPECT
TO TIMING/INTENSITY OF THIS SYSTEM WITH 12Z ECMWF ON THE
FASTER/WEAKER END OF THE GUIDANCE SPECTRUM AND THE NAM/GEM ON THE
SLOWER DEEPER END OF THE SPECTRUM. OFTEN TIMES THE SLOWER GUIDANCE
ENDS UP VERIFYING BETTER WITH THESE STRONGER SYSTEMS...SO TRENDED
THE GRIDS TOWARD THE NAM/GEM SOLUTION. THE GFS SUPPORTS THE IDEA OF
STRONGER SYSTEM BUT SUSPECT IT IS A BIT TOO FAST.
SYNOPTICALLY SPEAKING THE LARGE SCALE PATTERN AND EVOLUTION OF THIS
CYCLONE CONTINUE TO RAISE RED FLAGS FOR THE POTENTIAL OF A
SIGNIFICANT SEVERE WEATHER EPISODE IN THE REGION THURSDAY AFTERNOON
AND EVENING. THE KINEMATIC FIELDS ARE EXTREMELY IMPRESSIVE WITH 90-
100KT UPPER LEVEL JET NOSING INTO THE REGION IN THE AFTERNOON WITH
40KT+ LOW LEVEL JET RESULTING IN VERY FAVORABLE DEEP LAYER SHEAR
PROFILE FOR SEVERE WEATHER. THE MAGNITUDE OF LOW LEVEL SHEAR WHICH
WILL PLAY A ROLE IN THE MAGNITUDE OF A TORNADO THREAT VARIES
DEPENDING ON THE MODEL. THE DEEPER SOLUTIONS HAVE A MORE BACKED
SURFACE FLOW AND LARGER LOW LEVEL HODOGRAPHS AND WOULD BE MUCH MORE
WORRISOME REGARDING TORNADO THREAT.
THE LATEST MODEL RUNS THIS MORNING ALSO SUGGEST AN UNUSUALLY
IMPRESSIVE PLUME OF STEEP MID LEVEL LAPSE RATES FOR SO FAR EASTWARD
BECOME JUXTAPOSED OVER TOP A WARM AND HUMID AIR MASS WITH SURFACE
DEWPOINTS LIKELY IN THE 60S WITHIN THE WARM SECTOR. GIVEN THE
PROGGED INTENSITY OF THE SYSTEM SUSPECT THAT EVEN MORNING CONVECTION
WILL NOT BE ENOUGH TO PREVENT THE WARM FRONT FROM BLASTING NORTH AND
PLACING ENTIRE CWA IN THE HUMID/UNSTABLE WARM SECTOR BY AFTERNOON.
OBVIOUSLY THERE ARE A TON OF MESOSCALE DETAILS THAT CANNOT BE
RESOLVED AT THIS DISTANCE...INCLUDING STORM MODE AND COVERAGE. THERE
IS A LOT THAT CAN CHANGE BETWEEN NOW AND THURSDAY SO A SIGNIFICANT
SEVERE WEATHER EVENT IS FAR FROM A SURE THING...BUT GIVEN THE TRENDS
IN MODEL GUIDANCE AND SYNOPTIC PATTERN THERE IS DEFINITELY REASON
FOR CONCERN ABOUT THE SEVERE WEATHER AND TORNADO POTENTIAL THURSDAY
AFTERNOON AND EVENING.
COOLER/DRIER PACIFIC AIR WILL FILTER INTO THE REGION FRIDAY ON BRISK
WESTERLY WINDS...FOLLOWED BY A MODERATING TREND HEADING INTO THE
WEEKEND IN ADVANCE OF THE NEXT SYSTEM WHICH LOOKS TO ARRIVE LATE
SUNDAY OR MONDAY WITH OUR NEXT SHOT OF SHOWERS AND THUNDERSTORMS.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* IFR/LIFR THRU THE PERIOD.
* EASTERLY WINDS THRU THE PERIOD.
* CHANCE OF SHOWERS OVERNIGHT THRU MID MORNING...LOW CHANCE FOR
THUNDERSTORMS.
* SCATTERED THUNDERSTORMS LATE EVENING INTO THURSDAY MORNING. CMS
//DISCUSSION...UPDATED 06Z...
COMPLEX OF THUNDERSTORMS OVER SOUTHEAST IA WILL MOVE GENERALLY
EAST INTO WEST CENTRAL IL OVER THE NEXT FEW HOURS. SHORT TERM/HI
RES GUIDANCE CONTINUES TO SHOW THIS ACTIVITY REMAINING MAINLY
SOUTH OF THE TERMINALS AND SLOWLY WEAKENING TOWARD SUNRISE WITH
ADDITIONAL DEVELOPMENT POSSIBLE ACROSS EASTERN IL AND NORTHWEST
INDIANA...WITH SHOWERS OR POSSIBLE DRIZZLE FURTHER NORTH.
CONFIDENCE OF TSRA AT THE TERMINALS IS LOW ENOUGH TO REMOVE
MENTION OTHER THAN VICINITY AT GYY BUT TRENDS WILL NEED TO BE
MONITORED EARLY THIS MORNING.
SHOWER ACTIVITY COULD CONTINUE THRU THE DAY BUT GENERALLY SOUTH OF
THE TERMINALS SO HAVE MAINTAINED DRY CONDITIONS INTO EARLY THIS
EVENING. SHRA/TSRA ARE EXPECTED TO DEVELOP LATER THIS EVENING AND
CONTINUE...PERHAPS IN A COUPLE OF WAVES...THRU THURSDAY MORNING.
MEDIUM CONFIDENCE SO INCLUDED VICINITY MENTION BUT LOW CONFIDENCE
FOR TIMING/DURATION.
WINDS HAVE SHIFTED EAST/SOUTHEAST EARLY THIS MORNING AND SHOULD
GRADUALLY TURN BACK EASTERLY OVERNIGHT AND THEN NORTHEASTERLY
LATER THIS MORNING. SPEEDS ARE BIT UNCERTAIN AS GUIDANCE SUGGEST
SPEEDS COULD DIMINISH UNDER 10KTS BUT NOT CONFIDENT ENOUGH TO
LOWER PREVAILING SPEEDS JUST YET. WINDS WILL TURN BACK MORE EAST
OR SOUTHEAST LATER THIS EVENING AND OVERNIGHT...THEN LIKELY SHIFT
SOUTHERLY BY THURSDAY MORNING.
IFR/LIFR CIGS ARE EXPECTED TO CONTINUE THRU THE PERIOD...PERHAPS
LOWERING A BIT TOWARD SUNRISE WITH VISIBILITIES ALSO LOWERING. ITS
POSSIBLE CIGS MAY LIFT TO LOWER MVFR THIS AFTERNOON BUT CONFIDENCE
IS LOW. CMS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH FOR IFR/LIFR THRU THE PERIOD.
* MEDIUM FOR WINDS THRU THE PERIOD.
* MEDIUM FOR SHOWERS OVERNIGHT...LOW FOR INTENSITY/DURATION. LOW
FOR CHANCE OF THUNDERSTORMS TOWARD DAYBREAK.
* MEDIUM FOR THUNDERSTORMS TONIGHT...LOW ON TIMING/DURATION. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY...STRONG TSRA. MVFR. STRONG/GUSTY SOUTH/SOUTHWEST
WINDS.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...DRY/VFR. SOUTHEAST WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. MVFR POSSIBLE. SOUTH WINDS.
BEACHLER
&&
.MARINE...
340 PM CDT
A PERIOD OF ACTIVE WEATHER IS UNDERWAY FOR LAKE MICHIGAN. AS OF
TUESDAY AFTERNOON...A STATIONARY FRONTAL BOUNDARY LIES SOUTH OF THE
LAKE WHILE STRONG HIGH PRESSURE TRACKS ACROSS EASTERN ONTARIO INTO
QUEBEC. BETWEEN THE FRONTAL TROUGH TO THE SOUTH LAKE AND THE HIGH
TO THE NORTH...PERSISTENT NORTHEAST TO EAST WINDS OF 25 TO 30 KT
WILL COVER THE LAKE...WITH THE STRONGEST WINDS OVER THE NORTHERN
PORTIONS OF THE LAKE. DEWPOINTS HAVE BEEN INCREASING OVER THE
SOUTHERN PORTIONS OF THE LAKE...LEADING TO THE FORMATION OF DENSE
FOG...ESPECIALLY FOR THE SOUTHERN PORTIONS OF THE LAKE. LOW PRESSURE
DEVELOPING OVER THE WESTERN PLAINS WILL QUICKLY DEEPEN AND TRACK TO
NORTHERN WISCONSIN...FORCING THE STATIONARY FRONT NORTH AS A WARM
FRONT. WINDS WILL SHIFT FROM ELY-SELY TO SWLY FOLLOWING THE PASSAGE
OF THE WARM FRONT AND TEMPORARILY SUBSIDE...BUT A STRENGTHENING
GRADIENT AHEAD OF AN APPROACHING COLD FRONT WILL HELP STRENGTHEN
WINDS BACK TO 25 TO 30 KT. THE COLD FRONT TRAILING SOUTHWEST FROM
THE FAST-MOVING LOW WILL SWEEP ACROSS THE LAKE ON SATURDAY. HIGH
PRESSURE IS EXPECTED TO SPREAD ACROSS THE LAKE ON
SATURDAY...USHERING IN A PERIOD OF QUIETER WEATHER THAT SHOULD
PERSIST INTO EARLY NEXT WEEK.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN
UNTIL 5 AM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1159 PM CDT Tue Apr 7 2015
.UPDATE...
ISSUED AT 902 PM CDT TUE APR 7 2015
The stationary front is not making much progress northward yet
this evening. The latest sfc analysis shows the front still
lingering between I-72 and I-70 at 02z/9pm. Minor clearing has
developed toward SPI and Jacksonville, but the last hour clouds
have begun to re-develop in response to an inversion and trapped
low level moisture. Have continued with including fog along and
north of I-74 the rest of the night, with some dense fog ongoing
around BMI.
Low pressure is expected to advance along the front tonight,
helping to give it a northward push. Showers and storms should
accompany the arrival of the low, with the help of a 500mb
shortwave and increasing instability. Storms will increase in
coverage from west to east after 06z/1am. The storms will be
elevated, so hail will be more of a concern than very strong wind
gusts. No severe storms are anticipated with the wave of storms
later tonight, as the overall system dynamics will be weakening
with time as it moves across Illinois.
Forecast updates included: delaying the onset of precip for a few
more hours, diminished PoPs NW of the IL river late tonight,
adjusted hourly temps to try to match expected frontal boundary
movement northward. Updated forecast info is already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 301 PM CDT TUE APR 7 2015
A quasi stationary front remains over central IL between I-70 and
I-72. The frontal boundary should start to slowly push back
northward across central IL later this evening and overnight as 1007
mb low pressure over northeast KS tracks into central IL by Wed
morning. An MCS was bringing showers and a few thunderstorms to
southeast IL at mid afternoon while the strong to severe storms with
heavy rains were south of highway 50 and approaching the Ohio river
as they tracked eastward. pushes southward, wavering over central
Illinois, southerly flow will continue to bring in more boundary
layer moisture. Scattered showers and thunderstorms will develop
during tonight along this boundary over central IL as low pressure
approaches and frontal boundary starts to lift back north with ample
moisture. Some fog still lingering north of I-72 and added some fog
to areas north of this boundary tonight especially from I-74
northward. Lows tonight mostly in the upper 50s and lower 60s,
except cooler low to mid 50s from Galesburg to Peoria and
Bloomington northward which stays north of the boundary much of the
night.
&&
.LONG TERM...(Wednesday through Tuesday)
ISSUED AT 301 PM CDT TUE APR 7 2015
Not too much has changed in the large scale pattern/expected weather
over the next few days. However, things will continue to be tricky
with respect to the convective details and temperatures due to the
wobbling surface boundary and model disagreement in the ultimate
strength of the main low/frontal passage for Thursday.
The frontal boundary that currently lies west-east across the
Midwest will not move appreciably through Wednesday. Nearly
continuous WAA/isentropic ascent is progged through a deep layer
across the area until the main system arrives heading into Wednesday
night. Until the system approaches, forecast soundings (and 12Z KILX
sounding for that matter) suggest a persistent elevated mixed layer,
but also a fairly stout low level capping inversion. Moisture
continues to be lacking within the EML, so PoPs will stay on the
lower side for most of Wednesday.
The remnants of the Pacific Coast will help force the frontal
boundary back northward Wednesday night as it pushes across the
Plains. This will spread more widespread showers/storms across the
area as early as late Wednesday afternoon into Wednesday night.
There will be ample shear for some of the storms to be on the
stronger side, but they should be elevated in nature for the most
part and most apt to be hail producers.
The main low/cold front are still on tap to cross the region
Thursday into Thursday evening, although there are still
considerable timing/strength differences. The ECMWF continues to be
much weaker and (not surprisingly) several hours slower than the
building model consensus. Do not have a compelling reason to
disregard the ECMWF, but have leaned more toward the larger model
consensus. This scenario supports strong/severe storms across the
forecast area along/ahead of the front on Thursday, mainly during
the afternoon. Instability and shear profiles are both expected to
be more than respectable, with CAPE values averaging 1500-2500 j/kg,
and bulk shear values from 35-45 kts.
The cold front is expected to clear most of the area by late
Thursday evening, ushering in quieter weather until Sunday. Then,
another storm system will bring renewed shower/storm chances to
start out next week. However, model spread and run-to-run
consistency in the details continues to be poor at best. This is
resulting in an extended period of PoPs from what should only be one
system passage. Hopefully a better agreed upon solution develops
soon.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1155 PM CDT TUE APR 7 2015
A stationary front extending across central IL, just north of
I-70, is forecast to drift slowly northward overnight, in response
to the approach of a weakening low pressure center across
Missouri. The surface low and associated 500mb shortwave will help
trigger showers and storms in central IL the rest of the night.
A complex of storms has already developed west of PIA in SE Iowa.
The track of those storms looks to be just NW of PIA airport.
However, the HRRR and NCEP 4km WRF show additional development is
expected to the SE of the current storms. The new storms should
affect PIA and BMI between 07z and 12z, with the southern extend
possibly affecting the other terminal sites during that time.
SPI/DEC/CMI sites have returned to MVFR cloud heights. PIA/BMI
have remained LIFR due to 200ft cigs. BMI with vis now at 1/2sm FG.
Clouds are forecast to remain status quo for much of the night,
with some improvement as storms/showers pass near the terminals.
The weakening low pressure is still progged to advance across
central IL through early morning, dissipating before it reaches
Indiana. That will keep storm chances going through around 12z.
Additional storms are forecast to arrive tomorrow evening, per the
4km wrf.
ESE winds of 10-15kt will continue at 8-12kt overnight, with wind
directions highly dependent on how far north the stationary front
drifts by morning. Winds tomorrow morning could become variable
under the front, and eventually prevail from the N for PIA and
southwest for BMI/SPI/DEC/CMI. The GFS and NAM have differing wind
solutions, but went closer to the NAM with this set of TAFs.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Shimon
SHORT TERM...07
LONG TERM...Bak
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
423 AM EDT WED APR 8 2015
.SYNOPSIS...
ISSUED AT 423 AM EDT WED APR 8 2015
SEVERAL PERIODS OF RAIN WILL BE POSSIBLE DURING THE NEXT FEW DAYS
AS A STATIONARY FRONT REMAINS OVER THE REGION. A FEW SHOWERS AND
THUNDERSTORMS ARE EXPECTED WEDNESDAY MORNING BEFORE CLEARING OUT
WEDNESDAY AFTERNOON. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS
EXPECTED WEDNESDAY EVENING INTO THE OVERNIGHT HOURS. HIGHS WEDNESDAY
WILL RANGE FROM THE MID 50S NORTH OF THE FRONT IN SOUTHERN
MICHIGAN TO THE LOW 70S SOUTH OF THE FRONT SOUTH OF US 30. LOWS
WEDNESDAY NIGHT WILL BE IN THE 50S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT WED APR 8 2015
THE CLOUDY...COOL PATTERN CONTINUES AS WE MAINTAIN OUR POSITION
NORTH OF THE STATIONARY FRONT. A WEAK SHORTWAVE HAS TRIGGERED SOME
CONVECTION IN SE IOWA/ WESTERN ILLINOIS JUST NORTH OF THIS
STATIONARY FRONT. THE STORMS SEEM TO BE STRUGGLING WITH EASTWARD
EXTENT...LIKELY DUE TO A SLIGHTLY STRONGER CAP AT 650MB AND LESS
INFLUENCE FROM THE MID LEVEL WAVE. GIVEN THE REMAINING UNCERTAINTY
WITH THE EVOLUTION OF THIS CONVECTIVE COMPLEX AS IT MOVES
EASTWARD...HAVE KEPT POPS IN THE HIGH CHANCE RANGE.
EXPECT A LULL IN THE PRECIPITATION DURING THE AFTERNOON ON TODAY
AS WEAK SHORTWAVE RIDGING BUILDS IN AHEAD OF THE NEXT SHORTWAVE TO
EJECT OUT OF THE CENTRAL PLAINS. THIS WILL ALSO ALLOW FOR A LONG
AWAITED SHIFT NORTHWARD IN THE FRONTAL BOUNDARY. THIS PSEUDO WARM
FRONTAL SURGE WILL CREATE SIGNIFICANT BUST POTENTIAL FOR HIGH
TEMPERATURES ON TODAY. AREAS SOUTH OF THE SURFACE FRONT WILL
LIKELY WARM INTO THE LOW 70S WITH AREAS NORTH OF THE FRONT REMAINING
IN THE MID 50S. THE EXACT PROGRESSION OF THIS FRONT NORTHWARD WILL
DICTATE EXACTLY WHO SEES THE WARMER TEMPERATURES...BUT THE LATEST
HIRES GUIDANCE PUTS THE MAX NORTHWARD PROGRESSION RIGHT ALONG US30.
REGARDLESS OF THE EXACT PLACEMENT OF THIS FRONT...ITS PRESENCE
ACROSS OUR AREA MEANS WE WILL BE FAVORABLE FOR THUNDERSTORM
DEVELOPMENT DURING THE EVENING AND INTO THE OVERNIGHT HOURS. THERE
IS SIGNIFICANT UNCERTAINTY WRT TIMING OF STORMS ACROSS THE AREA. NAM
AND RAP HAVE A DECENT SHORTWAVE SPAWNING STORMS NORTH OF SAINT LOUIS
DURING THE AFTERNOON AND MOVING THAT MCS THROUGH OUR AREA AROUND
00Z. ONLY GLOBAL GUIDANCE WHICH EVEN HINTS AT A WAVE MOVING THROUGH
AT THAT TIME IS THE GEM AND THEREFORE GLOBAL GUIDANCE HOLDS OFF ON
CONVECTION UNTIL AFTER MIDNIGHT. IR SATELLITE DOES SHOW SOME COOLER
CLOUD TOPS IN SW KANSAS WHERE THIS SW IS CURRENTLY SUPPOSED TO
BE...SO AM INCLINED TO BELIEVE THE HIRES GUIDANCE AND DISCOUNT THE
GLOBAL GUIDANCE AS LACKING THE RESOLUTION TO PROPERLY RESOLVE THIS
WAVE. SEVERE RISK DOES EXIST WITH ANY STORMS THAT DO DEVELOP IN THIS
AFTERNOON TIMEFRAME GIVEN 40 TO 50 KNOTS OF DEEP LAYER SHEAR AND
1500 TO 2000 J/KG OF SBCAPE SOUTH OF THE SURFACE FRONT. EVEN IF THE
EARLY EVENING STORM DEVELOPMENT ON THE HIRES GUIDANCE DOESN`T
MATERIALIZE...THERE WILL STILL BE AN ISOLATED RISK OF SEVERE WEATHER
DURING THE OVERNIGHT HOURS GIVEN THE ~2000 J/KG OF MUCAPE AND 30
KNOT LLJ WITH THE REMAINING PRESENCE OF 35 TO 45 KNOTS OF DEEP LAYER
SHEAR.
&&
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 419 AM EDT WED APR 8 2015
PRIMARY CONCERNS FOR THE LONG TERM WILL CENTER ON CONVECTIVE/SEVERE
POTENTIAL THURSDAY/THURSDAY NIGHT...FOLLOWED BY RENEWED PRECIP
CHANCES EARLY NEXT WEEK.
SHOWERS/STORMS WILL LIKELY BE ONGOING THURSDAY MORNING AS UPPER JET
STREAK ASSOCIATED WITH SUBTROPICAL JET ENCROACHES ON THE OHIO RIVER
VALLEY. AXIS OF 40-50 KNOT SOUTHWESTERLY LOW LEVEL FLOW NOSING INTO
THE AREA BY MIDDAY WILL ALLOW FOR APPRECIABLE LOW/MID LEVEL
MOISTURE ADVECTION. MOISTURE CONVERGENCE AT NOSE OF STRONGER LOW
LEVEL FLOW SHOULD ALLOW POCKET OF PWATS NEAR 1.5 INCHES TO TRACK
ACROSS FORECAST AREA THURSDAY MORNING WITH AMPLE ELEVATED MOISTURE
FOR SHOWERS AND EMBEDDED THUNDER. POTENTIAL OF SOME LOCALLY HEAVIER
RAINFALL AMOUNTS STILL APPEARS TO BE INTACT THROUGH THURSDAY MORNING
IN ASSOCIATION WITH THIS FORCING ALONG WITH POTENTIAL OF SOME HAIL
GIVEN ELEVATED INSTABILITY AND RELATIVELY LOW FREEZING/WBZ ZERO
HEIGHTS BETWEEN 9-10K FT.
SOME DEGREE OF UNCERTAINTY REMAINS REGARDING CONVECTIVE EVOLUTION
THURSDAY AFTERNOON AND ASSOCIATED IMPACTS ON INSTABILITY MAGNITUDES
DURING PEAK HEATING. ATTENTION FOR THURSDAY AFTERNOON/NIGHT WILL
SHIFT UPSTREAM TO MORE ROBUST EASTERN PACIFIC WAVE WHICH SHOULD
ACQUIRE NEGATIVE TILT ACROSS THE WESTERN GREAT LAKES THURSDAY
EVENING. FRONTAL CONVERGENCE AND LEADING EDGE OF MID LEVEL DRY SLOT
SHOULD REGENERATE POTENTIALLY VIGOROUS CONVECTIVE DEVELOPMENT
ACROSS ILLINOIS DURING THE AFTERNOON...POSSIBLY TRACKING INTO
WESTERN PORTIONS OF LOCAL AREA THURSDAY EVENING. EXTENT OF ANY
THINNING CLOUD COVER THURSDAY AFTERNOON/LOW LEVEL TEMP TRENDS WILL
HAVE A BIG IMPACT ON INSTABILITY MAGNITUDES. GIVEN STRENGTH OF
BACKGROUND WIND FIELDS...A WIND THREAT MAY EVOLVE THURSDAY EVENING
EVEN IF AFTERNOON INSTABILITY RECOVERY IS SOMEWHAT LIMITED. AS
MENTIONED IN PREVIOUS FORECAST...A SOMEWHAT HIGHER SEVERE THREAT MAY
UNFOLD IF GREATER LATE AFTERNOON INSTABILITY CAN BE REALIZED GIVEN
SUBSTANTIAL SHEAR PROFILES...AND IN LIGHT OF DIFFERENTIAL
MOISTURE ADVECTION IMMEDIATELY PRECEDING SFC FRONT THURSDAY NIGHT
ASSOCIATED WITH THE DRY SLOT. SPC DAY2 OUTLOOK HAS MAINTAINED HIGHER
SVR PROBS ACROSS WESTERN THIRD/HALF OF AREA...WITH POSSIBILITY OF
WEAK NEAR SFC DIURNAL COOLING LATER THURSDAY EVENING DIMINISHING
INSTABILITY MAGNITUDES A BIT ACROSS THE EAST. ONLY TWEAK TO PREVIOUS
FORECAST WAS TO SLIGHTLY SPEED UP TIMING OF WEST TO EAST POP
REDUCTION LATER THURSDAY NIGHT FOLLOWING COLD FRONT PROGRESSION.
DID MAINTAIN SLIGHT CHANCE RAIN SHOWER POPS ACROSS THE FAR NORTH/FAR
EAST EARLY FRIDAY MORNING GIVEN LINGERING MID/UPPER FORCING WITH A
SERIES OF SMALLER SCALE WAVES ROTATING THROUGH LONGWAVE TROUGH...BUT
ADDITIONAL PRECIP AMOUNTS ACROSS THESE LOCATIONS SHOULD BE QUITE
LIGHT. BREEZY/WINDY CONDITIONS CAN ALSO BE EXPECTED WITH DEEPER POST
FRONTAL MIXING LATE THURSDAY NIGHT INTO FRIDAY. IT STILL APPEARS AS
THOUGH THE FRIDAY NIGHT THROUGH SUNDAY PERIOD SHOULD BE DRY WITH
NEAR SEASONABLE TEMPS UNDER INFLUENCE OF MID/UPPER LEVEL RIDGING.
LOW LEVEL ANTICYCLONE TO DEPART TO THE EAST SUNDAY NIGHT INTO MONDAY
ALLOWING FOR A FAIRLY QUICK TRANSITION TO STRONGER LOW LEVEL
MOISTURE TRANSPORT FOR MONDAY. GOOD MOISTURE AVAILABILITY AND
APPROACH OF CUT-OFF SOUTHERN STREAM PV ANOMALY FOR TUE/WED SHOULD
KEEP CHANCES OF SHOWERS AND STORMS GOING THROUGH THE END OF THE
PERIOD AS THIS WAVE EVENTUALLY DAMPENS ACROSS THE AREA. THIS PATTERN
WILL ALSO BE CONDUCIVE FOR SHARPLY MODERATING TEMPERATURES ONCE
AGAIN FOR EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 128 AM EDT WED APR 8 2015
IFR CONDITIONS EXPECTED FOR A FEW MORE HOURS AT KSBN BEFORE LOWER
ALT MIN CIGS ADVECT IN AFTER 10Z. THESE LOW CIGS WILL PERSIST
AT BOTH TERMINALS THROUGH MID DAY WHEN A WARM FRONT WILL LIFT
NORTHWARD INTO THE AREA. WINDS WILL QUICKLY SHIFT AROUND TO
SOUTHWESTERLY SOUTH OF THIS FRONT AT KFWA AND WILL SWITCH TO
NORTHWESTERLY AT KSBN AS A WEAK WAVE TRAVERSES THIS FRONT. THIS
WAVE MAY BRING A FEW STORMS THROUGH THE AREA AROUND 00Z...BUT WILL
WAIT FOR LATER TAF ISSUANCES TO INTRODUCE ANY TSRA MENTION.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR LMZ043-046.
&&
$$
SYNOPSIS...BENTLEY
SHORT TERM...BENTLEY
LONG TERM...MARSILI
AVIATION...BENTLEY
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WWW.TWITTER.COM/NWSIWX
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AREA FORECAST DISCUSSION
NWS WICHITA KS
333 AM CDT WED APR 8 2015
.SYNOPSIS...
ISSUED AT 332 AM CDT WED APR 8 2015
WATER VAPOR IMAGERY SHOWS A STRONG SHORTWAVE TRACKING OVER THE
CENTRAL GREAT BASIN. AT THE SURFACE...LOW PRESSURE IS SITUATED
OVER SE CO WITH THE SYNOPTIC FRONT STRETCHING FROM JUST NORTH OF
KGAG TO BETWEEN KCNU AND KPPF. MEANWHILE...A LOSE DRYLINE EXTENDS
ACROSS THE OK PANHANDLE AND INTO WEST TX.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
ELEVATED STORMS DEVELOPED A COUPLE HOURS AGO OVER THE FLINT HILLS
IN RESPONSE TO A RAPID INCREASE IN MOISTURE TRANSPORT IN THE
850-700MB LAYER. THIS ACTIVITY SHOULD FOR THE MOST PART STAY
NORTHEAST OF THE FORECAST AREA.
SIGNIFICANT SEVERE STORMS STILL LOOK LIKELY THIS AFTERNOON AND
EVENING. CURRENTLY HAVE A LEAN TO THE RAP13 DUE TO ITS PERFORMANCE
WITH THE CONVECTION THAT OCCURRED OVER THE LAST SEVERAL HOURS OVER
SE KS. IN ADDITION...IT SEEMS TO BE DOING A DECENT JOB CAPTURING
THE CURRENT ELEVATED CONVECTION. THE GFS LIFTS THE WARM FRONT
MUCH FURTHER NORTH COMPARED TO THE NAM AND RAP WITH THE FRONT
ALONG I-70. MEANWHILE THE RAP AND NAM LIFT THE FRONT TO JUST NORTH
OF KICT TO SOUTH OF KSLN.
CURRENT THINKING IS THAT THE TRIPLE POINT BY LATE AFTERNOON WILL
BE SITUATED JUST SOUTHWEST OF THE FORECAST AREA NEAR OR JUST NORTH
OF KGAG WITH THE SYNOPTIC FRONT EXTENDING TO THE NORTHEAST NEAR
KICT AND THEN TO NEAR KEMP. WATER VAPOR IMAGERY SHOWS A LEAD
IMPULSE/JET MAX OVER NORTHERN BAJA. EXPECTING STORMS TO DEVELOP
NEAR THE TRIPLE POINT AS THIS FEATURE MOVES OUT OF THE SOUTHERN
HIGH PLAINS. ADDITIONAL DEVELOPMENT CAN THEN BE EXPECTED NORTHEAST
ALONG THE SYNOPTIC FRONT. IT SEEMS WITH EACH MODEL RUN THE DEEP
LAYER SHEAR HAS INCREASED SLIGHTLY AND THE 00Z RUNS WERE NO
EXCEPTION...WITH AROUND 50KTS OF 0-6KM SHEAR AND 65-80KTS OF
0-8KM SHEAR OVER SOUTH CENTRAL KS. THESE SHEAR VALUES WILL COMBINE
WITH 2000-3000J/KG OF CAPE TO ALLOW ANY STORM THAT DEVELOPS TO
QUICKLY BECOME SEVERE. THE SCARY PART IS THAT WITH THE
RETREATING DRYLINE AFTER 00Z...THE ENVIRONMENT ACTUALLY BECOMES
MORE FAVORABLE AFTER DARK AS WINDS BACK AND THE LOW LEVEL JET GETS
GOING. SO NOT OUT OF THE QUESTION TO GET A TORNADO AFTER DARK OVER
SOUTH CENTRAL KS. THE BEST TORNADO POTENTIAL TONIGHT LOOKS TO BE
SOUTH OF HIGHWAY 50 AND WEST OF HIGHWAY 99. IF THE NAM AND RAP13
VERIFIES...SEVERE STORMS OVER CENTRAL KS WOULD BE LESS LIKELY.
BY 12Z THU...THE SHORTWAVE WILL BE TRACKING ACROSS NORTHERN
KS/NEBRASKA WITH THE SYNOPTIC FRONT CATCHING UP TO THE DRYLINE AND
SURGING EAST. WHILE THERE MAYBE SOME REMNANT STORMS OVER SE KS
AROUND SUNRISE...THE BULK OF THE ACTIVITY AFTER 15Z THU WILL BE
EAST OF THE FORECAST AREA. IT NOW LOOKS LIKE THE BETTER CHANCES
FOR PRECIP ON THE BACKSIDE OF THIS SYSTEM SHOULD STAY NORTH OF THE
FORECAST AREA THU.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
A LARGE AREA OF HIGH PRESSURE WILL ENCOMPASS THE PLAINS FOR FRI
WITH TEMPS FINALLY GETTING BACK TO SEASONAL VALUES. BOTH THE GFS
AND ECMWF BRING A SOUTHERN STREAM SYSTEM OUT OF THE BAJA REGION
AND INTO WEST TX BY SUN EVENING. WARM ADVECTION AHEAD OF THIS
SYSTEM MAY BRING SOME SCATTERED SHOWERS AND STORMS SAT BUT THE
BETTER PRECIP CHANCES LOOK TO ARRIVE SUN NIGHT AND CONTINUE
THROUGH MON WHEN THE IMPULSE LIFTS ACROSS THE PLAINS. THE GFS HAS
THIS FEATURE QUITE A BIT FURTHER WEST COMPARED TO THE ECMWF WHICH
RESULTS IN THE ECMWF BEING THE WETTER SOLUTION.
LAWSON
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1147 PM CDT TUE APR 7 2015
IFR/LIFR CIGS CONTINUE TO SPREAD SOUTH AND EAST IN THE WAKE OF THE
FRONT WHILE SEVERE STORMS LINGER ACROSS SOUTHEAST KANSAS THROUGH
THE PREDAWN HOURS. A WARM FRONT IS PROGGED TO LIFT NORTH DURING
THE DAY ON WEDNESDAY ALLOWING MVFR/VFR TO RETURN DURING THE LATE
MORNING/EARLY AFTERNOON. WINDS ARE EXPECTED TO SHIFT TO THE SOUTH
WITH SCATTERED STORMS DEVELOPING ALONG A DRY LINE AND ALONG THE
WARM FRONT LATE WED AFTERNOON/EVENING SPREADING EASTWARD ACROSS
THE AREA.
&&
.FIRE WEATHER...
ISSUED AT 332 AM CDT WED APR 8 2015
MAIN FIRE WEATHER CONCERNS LOOK TO ON THURSDAY.
EVEN WITH PLENTY OF LOW LEVEL MOISTURE...VERY HIGH FIRE DANGER
WILL BE IN PLACE OVER SOUTH CENTRAL AND SE KS DUE TO GUSTY SOUTH
WINDS. HOWEVER...THE CRITICAL FIRE WEATHER DAY LOOKS TO BE THU.
THIS IS WHEN STRONG NW WINDS WILL BE IN PLACE BY THE AFTERNOON
HOURS ALONG WITH RH`S IN THE 35-45% RANGE. WIND SPEEDS THU
AFTERNOON WILL BE IN THE 20-30 MPH RANGE WITH HIGHER GUSTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 84 55 71 40 / 30 30 10 0
HUTCHINSON 80 51 68 37 / 30 20 10 0
NEWTON 81 53 68 39 / 30 30 10 0
ELDORADO 82 59 70 40 / 30 40 10 10
WINFIELD-KWLD 83 60 74 42 / 30 30 10 0
RUSSELL 70 47 64 34 / 20 20 20 10
GREAT BEND 74 47 65 34 / 20 10 10 0
SALINA 73 50 65 36 / 30 30 20 10
MCPHERSON 77 50 67 37 / 30 30 10 10
COFFEYVILLE 81 65 77 44 / 30 40 30 10
CHANUTE 80 64 75 42 / 30 50 30 10
IOLA 79 63 75 42 / 40 50 30 10
PARSONS-KPPF 81 64 76 43 / 30 50 30 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
422 AM EDT WED APR 8 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM EDT WED APR 8 2015
07Z SFC ANALYSIS SHOWS A STATIONARY BOUNDARY JUST NORTH OF
KENTUCKY PLACING THE AREA IN A WARM AND HUMID AIR MASS. THE
CONVECTION OF THE PAST DAY AND EVENING LEFT PLENTY OF GROUND
MOISTURE BEHIND AND NOW THAT CLOUDS ARE CLEARING OFF TO THE
EAST...EXPECT WIDESPREAD FOG TO DEVELOP AND BECOME LOCALLY DENSE
THIS MORNING. ALREADY JKL...SME...AND LOZ ARE SEEING DENSE FOG. AS
A RESULT...A DENSE FOG ADVISORY MAY BE NEEDED FOR MUCH OF THE
AREA THROUGH DAWN. OTHERWISE...TEMPERATURES ARE IN THE MID TO
UPPER 50S FOR MOST LOCATIONS WHILE DEWPOINTS ARE GENERALLY WITHIN
A DEGREE OF THE DRY BULB TEMP...ALSO WINDS REMAIN LIGHT AND
VARIABLE.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST. THEY ALL SHOW SOUTHWEST FLOW OVER
KENTUCKY WITH PACKETS OF ENERGY PASSING THROUGH THE REGION EVERY
FEW HOURS. SOME HEIGHT FALLS WILL GET INTO THE MIX LATE IN THE
PERIOD ON THURSDAY AS A LARGER TROUGH SWEEPS EAST AND INTO THE
UPPER MIDWEST. THE KEY TO THIS UNSETTLED PATTERN WILL BE THE
SMALLER FEATURES THAT THE HIGHER RESOLUTION MODELS HAVE A BETTER
CHANCE OF CATCHING. EVEN SO...THE CONFIDENCE IN ANY PARTICULAR
SOLUTION IS LOW SO THE FORECAST HAS AN ELEMENT OF HEDGING TO IT
WITH THE HRRR AND NAM12 FAVORED. THE NAM12 ACTUALLY DID A DECENT
JOB DEPICTING THE CONVECTION OF THE PAST DAY SO AM INCLINED TO
GIVE IT HIGHER WEIGHTING TODAY.
SENSIBLE WEATHER WILL LIKELY BE A REPEAT OF TUESDAY WITH A CLUSTER
OF STRONG TO SEVERE THUNDERSTORMS POSSIBLY DEVELOPING BY EARLY
AFTERNOON AND TRACKING THROUGH THE NORTHERN AND CENTRAL PORTION
OF THE CWA. THIS IS THE SAME PLACE THAT WAS HIT HARD YESTERDAY AND
PWS WILL BE SIMILAR TODAY...SO CONSIDERED A FLASH FLOOD WATCH FOR
THESE LOCATIONS. HOWEVER...THE UNCERTAINTY IS STILL TOO HIGH
BARRING OBVIOUS UPSTREAM DEVELOPMENT SO WILL HIT THIS THREAT WITH
AN SPS FOR NOW. THE CONVECTION SHOULD DIE DOWN LATER IN THE
EVENING WITH PATCHY FOG...LOCALLY DENSE AGAIN...A CONCERN. THE
SET UP REMAINS SIMILAR FOR STORMS ON THURSDAY...IF NOT A TAD
BETTER AS THE MAIN TROUGH APPROACHES. ACCORDINGLY...HAVE CONTINUED
THE FAIRLY HIGH CHANCES FOR SHOWERS AND STORMS INTO THURSDAY
AFTERNOON AND EVENING.
AGAIN USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR
THE WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON
TERRAIN FOR TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSE
TO OR A BIT HIGHER THAN A BLEND OF THE MAV AND MET VALUES THROUGH
THE PERIOD.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 421 AM EDT WED APR 8 2015
AN UPPER LEVEL TROUGH...WITH SEVERAL SHORTWAVES EMBEDDED AND
ROTATING WITHIN IT...WILL PUSH FROM THE UPPER MISSISSIPPI VALLEY
EASTWARD FROM 0Z FRIDAY AND THROUGH THE DAY FRIDAY. OVERNIGHT FRIDAY
AND INTO THE DAY SATURDAY...THIS WAVE WILL WEAKEN AND CONTINUE TO
SHIFT EASTWARD...WHILE BUILDING HEIGHTS AND DEAMPLIFIED RIDGING
TAKES HOLD ACROSS THE OHIO RIVER VALLEY. LONG RANGE MODELS ARE IN
AGREEMENT OF THIS FLOW BECOMING ZONAL THROUGH SUNDAY...WITH A
SHORTWAVE DEVELOPING AND RIDING EASTWARD ACROSS KY LATE IN THE DAY
AND CONTINUING INTO MONDAY. UNFORTUNATELY FOR THE REST OF THE
EXTENDED...THE FEATURES ARE WELL AGREED UPON...BUT THE TIMING AND
PLACEMENT IS NOT. SUNDAY NIGHT/MONDAY MORNING A UPPER LEVEL CLOSED
LOW WILL LIKELY DEVELOP OVER THE TX/NM AREA...CAUSING AMPLIFICATION
AND EVENTUALLY FALLING HEIGHTS ACROSS KY AS THE LOW STARTS TO MOVE
NEWARD DURING THE DAY MONDAY...LOSING CONSIDERABLE STRENGTH AS IT
REACHES THE UPPER MISSISSIPPI VALLEY BY TUESDAY. MULTIPLE WEAKER
SHORTWAVES WILL MOVE AROUND THESE CLOSED LOWS...TRAVELING DIRECTLY
INTO THE OHIO RIVER VALLEY.
AT THE SURFACE...A LOW PRESSURE SYSTEM WILL BE COLLOCATED WITH THE
UPPER LEVEL TROUGH ON FRIDAY AND FOLLOW THE TRACK NORTHEASTWARD
ACROSS THE GREAT LAKES. THIS WILL SEND A COLD FRONT EASTWARD AND
INTO THE STATE OF KY...STARTING OFF IN THE FAR WEST AROUND 0Z TO
3Z...AND REACHING THE JKL CWA BY LATE MORNING FRIDAY BEFORE QUICKLY
SHIFTING EASTWARD IN THE AFTERNOON...JUST AS THE UPPER LEVEL TROUGH
EXITS. BEST INSTABILITY AND MOISTURE WILL BE LOCATED ALONG AND JUST
AHEAD OF THE FRONT...WITH SHOWERS AND THUNDERSTORMS CHANCES EXPECTED
TO INCREASE THROUGH FRIDAY MORNING...BEFORE QUICKLY TAPERING OFF
ONCE THE FRONT PASSES THROUGH AND A STRONG SHOT OF DRIER AND COOLER
NRLY FLOW MOVES IN.
AS HEIGHTS BUILD SATURDAY INTO SATURDAY NIGHT...EXPECT SURFACE HIGH
PRESSURE TO BE IN CHARGE...WITH LIGHT WINDS AND GENERALLY CLEAR
SKIES. THE COULD CREATE SOME RIDGE VALLEY SPLIT CONDITIONS FOR
OVERNIGHT LOWS...AS WAS REFLECTED IN THE FORECAST. BY SUNDAY...THE
NEXT SHORTWAVE WILL BEGIN ENCROACHING UPON THE REGION...WITH YET
ANOTHER SURFACE LOW LOCATED JUST TO OUR SW. STRONG SRLY FLOW WILL
TAKE HOLD...WHICH COUPLED WITH INSTABILITY/LIFT FROM THE NEARBY
SYSTEM...WILL CREATE ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS SUNDAY EVENING AND INTO THE DAY MONDAY. FINALLY...THE
FUN CONTINUES AS SEVERAL MORE SHORTWAVES TRAVERSE THE UPPER LEVEL
TROUGH AND BRING UNSETTLED WEATHER TO THE REGION TO CONTINUE OUT THE
REMAINDER OF THE EXTENDED. GIVEN THE TIMING AND PLACEMENT
DISCREPANCIES OF THE LONG RANGE MODELS...CONTINUED WITH A MODEL
BLEND AT THIS TIME. HOWEVER...ONE NOTE...IF THE GFS40 MODEL PANS
OUT...SOME OF THESE SYSTEMS COULD PUT DOWN SOME HEAVY RAINS...WITH
PWATS TOPPING OUT ABOVE 1.3 TUESDAY AFTERNOON AND EVENING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 230 AM EDT WED APR 8 2015
NOW THAT THE CONVECTION HAS MOVED ON EAST...EXPECT SOME FOG AND
LOW CEILINGS TO DEVELOP LATER TONIGHT AND BUILD TOWARDS DAWN WITH
A TIME OF LIFR POSSIBLE. ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS IS EXPECTED THIS AFTERNOON. HAVE INCLUDED A VCTS
FOR THIS WITH MORE REFINEMENT POSSIBLE WITH FUTURE TAF ISSUANCES
AS THE TIMING AND EFFECTS OF THIS NEXT WAVE BECOME MORE CLEAR.
WINDS WILL REMAIN MAINLY LIGHT FROM THE SOUTH OUTSIDE OF
THUNDERSTORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR KYZ044-
050>052-058>060-068-069-079-080-083>088-104-106>120.
&&
$$
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
400 AM EDT WED APR 8 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM EDT WED APR 8 2015
07Z SFC ANALYSIS SHOWS A STATIONARY BOUNDARY JUST NORTH OF
KENTUCKY PLACING THE AREA IN A WARM AND HUMID AIR MASS. THE
CONVECTION OF THE PAST DAY AND EVENING LEFT PLENTY OF GROUND
MOISTURE BEHIND AND NOW THAT CLOUDS ARE CLEARING OFF TO THE
EAST...EXPECT WIDESPREAD FOG TO DEVELOP AND BECOME LOCALLY DENSE
THIS MORNING. ALREADY JKL...SME...AND LOZ ARE SEEING DENSE FOG. AS
A RESULT...A DENSE FOG ADVISORY MAY BE NEEDED FOR MUCH OF THE
AREA THROUGH DAWN. OTHERWISE...TEMPERATURES ARE IN THE MID TO
UPPER 50S FOR MOST LOCATIONS WHILE DEWPOINTS ARE GENERALLY WITHIN
A DEGREE OF THE DRY BULB TEMP...ALSO WINDS REMAIN LIGHT AND
VARIABLE.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST. THEY ALL SHOW SOUTHWEST FLOW OVER
KENTUCKY WITH PACKETS OF ENERGY PASSING THROUGH THE REGION EVERY
FEW HOURS. SOME HEIGHT FALLS WILL GET INTO THE MIX LATE IN THE
PERIOD ON THURSDAY AS A LARGER TROUGH SWEEPS EAST AND INTO THE
UPPER MIDWEST. THE KEY TO THIS UNSETTLED PATTERN WILL BE THE
SMALLER FEATURES THAT THE HIGHER RESOLUTION MODELS HAVE A BETTER
CHANCE OF CATCHING. EVEN SO...THE CONFIDENCE IN ANY PARTICULAR
SOLUTION IS LOW SO THE FORECAST HAS AN ELEMENT OF HEDGING TO IT
WITH THE HRRR AND NAM12 FAVORED. THE NAM12 ACTUALLY DID A DECENT
JOB DEPICTING THE CONVECTION OF THE PAST DAY SO AM INCLINED TO
GIVE IT HIGHER WEIGHTING TODAY.
SENSIBLE WEATHER WILL LIKELY BE A REPEAT OF TUESDAY WITH A CLUSTER
OF STRONG TO SEVERE THUNDERSTORMS POSSIBLY DEVELOPING BY EARLY
AFTERNOON AND TRACKING THROUGH THE NORTHERN AND CENTRAL PORTION
OF THE CWA. THIS IS THE SAME PLACE THAT WAS HIT HARD YESTERDAY AND
PWS WILL BE SIMILAR TODAY...SO CONSIDERED A FLASH FLOOD WATCH FOR
THESE LOCATIONS. HOWEVER...THE UNCERTAINTY IS STILL TOO HIGH
BARRING OBVIOUS UPSTREAM DEVELOPMENT SO WILL HIT THIS THREAT WITH
AN SPS FOR NOW. THE CONVECTION SHOULD DIE DOWN LATER IN THE
EVENING WITH PATCHY FOG...LOCALLY DENSE AGAIN...A CONCERN. THE
SET UP REMAINS SIMILAR FOR STORMS ON THURSDAY...IF NOT A TAD
BETTER AS THE MAIN TROUGH APPROACHES. ACCORDINGLY...HAVE CONTINUED
THE FAIRLY HIGH CHANCES FOR SHOWERS AND STORMS INTO THURSDAY
AFTERNOON AND EVENING.
AGAIN USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR
THE WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON
TERRAIN FOR TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSE
TO OR A BIT HIGHER THAN A BLEND OF THE MAV AND MET VALUES THROUGH
THE PERIOD.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 400 AM EDT WED APR 8 2015
WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 230 AM EDT WED APR 8 2015
NOW THAT THE CONVECTION HAS MOVED ON EAST...EXPECT SOME FOG AND
LOW CEILINGS TO DEVELOP LATER TONIGHT AND BUILD TOWARDS DAWN WITH
A TIME OF LIFR POSSIBLE. ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS IS EXPECTED THIS AFTERNOON. HAVE INCLUDED A VCTS
FOR THIS WITH MORE REFINEMENT POSSIBLE WITH FUTURE TAF ISSUANCES
AS THE TIMING AND EFFECTS OF THIS NEXT WAVE BECOME MORE CLEAR.
WINDS WILL REMAIN MAINLY LIGHT FROM THE SOUTH OUTSIDE OF
THUNDERSTORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
449 AM EDT WED APR 8 2015
.SYNOPSIS...
A BACKDOOR COLD FRONT WILL DROP SOUTH ACROSS THE LOCAL AREA EARLY
TODAY THROUGH TONIGHT. THE FRONT THEN WEAKENS AND LIFTS BACK
NORTH AS A WARM FRONT ON THURSDAY. ANOTHER COLD FRONT CROSSES THE
REGION LATE FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 405 AM EDT WED...
LATEST SURFACE ANALYSIS FEATURES SFC LOW PRESSURE IN PLACE OVER
THE CENTRAL HIGH PLAINS, WITH A QUASI-STATIONARY FRONTAL BOUNDARY
DRAPED ACROSS THE MID MS VLY OVER INTO THE OHIO VLY AND THE LWR
EASTERN SHORE. NOTING SOME POCKETS OF SHRAS ACROSS THE AREA ON
REGIONAL RADAR MOSAIC IN ASSOCIATION WITH A FEW WEAK DISTURBANCES.
A FEW SCT SHRAS ARE CURRENTLY PUSHING EAST ON THE SOUTHERN
PERIPHERY OF THE FRONTAL ZONE ACROSS THE LWR EASTERN SHORE THIS
MORNING. MEANWHILE TO THE WEST, A MORE SUBSTANTIAL AREA OF SHRAS
IN ASSOCIATION WITH DECAYING CONVECTIVE COMPLEX THAT ROLLED ACROSS
THE OHIO RVR VALLEY LAST NIGHT IS CURRENTLY PUSHING FROM E
WV/WESTERN VA OVER TO THE PIEDMONT IN THE FORM OF SOME LIGHT TO
MODERATE RAIN SHRAS. LATEST HRRR AND TO A LESSER EXTENT THE 00Z
NAM HAVE BEST HANDLED THIS FEATURE THUS FAR... AND HAVE THEREFORE
LEANED THE FORECAST IN THIS DIRECTION FOR THE NEAR TERM. HAVE GONE
WITH A BRIEF 4-6 HR PERIOD OF LIKELY SHRAS THIS MORNING MAINLY IN
THE WARM SECTOR...WITH THE BEST RAIN CHANCES FROM THE EASTERN
PIEDMONT/WEST OF RIC METRO EARLY THIS MORNING...REACHING THE I-95
CORRIDOR BY DAWN AND EVENTUALLY SOUTH CENTRAL VA/HAMPTON ROADS BY
MID TO LATE MORNING. EXPECT LESS SHRA ACTIVITY THIS AFTN BEHIND
DEPARTING SHORTWAVE AND HV THEREFORE CUT BACK ON POP FOR THE AFTN.
EXPECT THE FRONT TO THE NORTH TO DROP SOUTH-SOUTHEAST IN BACKDOOR
FASHION THIS MORNING, BRINGING ABOUT A WIND SHIFT TO THE NE FROM
MIDDAY INTO THE AFTN. TEMPERATURES WILL STABILIZE TO FALL SLIGHTLY
ACROSS THE NORTHERN NECK/EASTERN SHORE, AS TEMPERATURES WARM INTO
THE LOW TO MID 70S IN THE WARM SECTOR OVER INLAND SECTIONS ALONG
AND SOUTH OF THE VA/NC BORDER. FARTHER NORTH, LOOK FOR HIGHS IN
THE U40S NEAR OCEAN CITY...LOW TO MID 50S OVER THE NORTHERN HALF
OF THE AREA.
EXPECT ANOTHER ROUND OF CONVECTION BY EARLY EVENING AS NEXT
DISTURBANCE NOW OVER THE MID MO VLY TRANSLATES EAST. WILL INCREASE
POP AGAIN BRIEFLY TONIGHT AS DISTURBANCE MOVES ALONG THE FRONT,
IN PLACE ALONG OR JUST SOUTH OF THE VA/NC BORDER THIS EVENING.
RAIN CHANCES DROP OFF AGAIN TONIGHT BEHIND THIS FEATURE
OVERNIGHT. COOLER TONIGHT IN MOIST NE FLOW BEHIND THE FRONT, WITH
LOWS IN THE 40S NE TO MID 50S SW SECTIONS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 448 AM EDT WED...
THE FRONT WILL WEAKEN, WITH DEVELOPING SW FLOW EVENTUALLY PUSHING
IT BACK NWD AS A WARM FRONT BY THU AFTN. HIGHS THU WILL RANGE
FROM THE 50S ON THE LWR ERN SHORE TO THE U60S TO L70S WITH MORE
TIME IN THE WARM SECTOR ACROSS FAR SWRN/WRN AREAS. HAVE MADE A
MODEST DOWNWARD ADJUSTMENT ACROSS THE NORTHERN HALF OF THE AREA
WITH ONGOING NE FLOW. POPS REMAIN IN CHANCE RANGE AS SEVERAL WEAK
DISTURBANCES WILL RESULT IN TWO PERIODS FOR SCT SHRAS...MAINLY
ACROSS THE NORTH IN THE MORNING AND ACROSS CENTRAL AND SOUTHERN
ZONES ALONG THE FROTNAL ZONE.
SFC LOW OVER THE PLAINS WILL TRACK NE INTO THE GREAT LAKES LATE
THU/FRI WITH THE ASSOCIATED COLD FRONT CROSSING INTO OUR AREA
FM THE WEST LATE IN THE DAY ON FRI/FRI NGT. CHANCES OF ADDITIONAL
SHRAS/STORMS INCREASE FM W TO E THRU THE DAY FRI...WITH THE BEST
CHANCE (60% POPS) IN THE AFTN/EVE HRS. SOME TSTMS MAY HAVE STRONG
GUSTY WINDS AND HEAVY RAIN...AND HV MAINTAINED THIS MENTION IN
THE HWO. MORE SUN/COMPRESSIONAL HEATING AHEAD OF FRONT WILL ALLOW
FOR MUCH WARMER TEMPS ON FRIDAY AS THE REGION RETURNS INTO THE
WARM SECTOR. LOOK FOR HIGHS IN THE MID 70S TO LOW 80S...WITH SOME
MID 80S POSSIBLE ACROSS THE SOUTH IF CLEARING OCCURS A BIT QUICKER
THAN PRESENTLY MODELED.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 446 PM EDT TUE...
SFC CDFNT TO PUSH OFF THE CST AFT MDNGT FRI NGT...TO BE FOLLOWED
BY HI PRES FM THE WNW BUILDING OVR THE RGN THIS WKND. CONTG HI
CHC/LIKELY POPS FRI EVE...THEN TAPERING OFF W-E THROUGH LT FRI
NGT/EARLY SAT MRNG. XPCG CLRG ON SAT AS DRYING AIR FM THE WNW
SPREADS OVR THE RGN. THE HIGH MOVES OFF THE CST BY EARLY NEXT
WK...RESULTING IN WNDS BECOMING SSW...AND MOISTURE GRADUALLY
INCRSG. LO TEMPS FRI NGT FM THE M50S NW TO ARND 60F SE. HI TEMPS
SAT IN THE L/M60S AT THE CST...TO L70S INLAND. LO TEMPS SAT NGT FM
THE M40S NW TO L50S SE. HI TEMPS SUN NR 60F AT THE CST...TO 65 TO
70F ELSW. HI TEMPS MON/TUE FM THE M60S TO M70S.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
A BACKDOOR COLD FRONT IS DROPPING SOUTH INTO FAR NERN COUNTIES OF
THE FA EARLY THIS MORNING. VARIABLE BR WITH VISIBILITIES RANGING
FROM 1-5SM ACROSS THE REGION...WITH POCKETS OF FG WITH
VISIBILITIES FROM 1/4-1/2SM. NORTH OF THE FRONTAL BOUNDARY...WINDS
ARE NE AROUND 10-15KT. SOUTH OF THE BOUNDARY...WINDS ARE LIGHT
FROM THE SOUTH. AS THE FRONT SAGS SWD TODAY...EXPECT SIMILAR WIND
SHIFTS AND SPEEDS AS THE DAY PROGRESSES. MEANWHILE...A DECENT
SWATH OF RAIN SHOWERS ARE PUSHING WWD INTO THE ERN PIEDMONT AS OF
08/0800Z. RAIN WILL CONTINUE TO PUSH EWD ACROSS THE REGION
TODAY...BECOMING MORE FOCUSED ACROSS THE SOUTH WHERE THE FRONTAL
BOUNDARY IS LOCATED. EXPECT A COMBINATION OF MVFR/IFR CIGS IN RAIN
SHOWERS TODAY. PRECIP COMES TO AN END BY MID TO LATE
EVENING...WITH AREAS OF FOG EXPECTED TO DEVELOP QUICKLY OVERNIGHT.
CIGS ARE EXPECTED TO BE AROUND 400FT AGL WITH VARIABLE
VISIBILITIES IN IFR/MVFR CATEGORIES. THE BACKDOOR FRONT STALLS
ACROSS THE CAROLINAS WED NIGHT/THU AND CONDITIONS SHOULD BE SLOW
TO IMPROVE THU MORNING. THE FRONT LIFTS NWD THROUGH THE REGION THU
NIGHT/EARLY FRI MORNING. BREEZY CONDITIONS ANTICIPATED FRI AHEAD
OF AN APPROACHING COLD FRONT WHICH IS EXPECTED TO CROSS THE REGION
FRI EVENING. HIGH PRESSURE RETURNS TO THE REGION SAT/SUN.
&&
.MARINE...
SFC LOW PRESSURE WILL MOVE ACROSS THE WATERS INVOF A BACKDOOR COLD
FRONT...WHICH IS DROPPING DOWN ACROSS THE VA EASTERN SHORE AS OF
300 AM THIS MORNING. WINDS ARE GENERALLY LIGHT FROM THE S-SW SOUTH
OF THE FRONT...WITH BREEZY N-NE WINDS 10-20KT WITH GUSTS AROUND
25KT NORTH OF THE FRONT. AM ALREADY SEEING AN INCREASE IN WIND
SPEEDS IN CHES BAY NORTH OF TANGIER ISLAND AND ALONG THE ATLANTIC
COAST FROM FENWICK ISLAND TO PARRAMORE ISLAND. THE FRONT WILL
GRADUALLY DROP SWD THROUGH THE REST OF TODAY...STALLING ACROSS THE
CAROLINAS TONIGHT INTO THU. EXPECT NNE WINDS TO INCREASE OVER THE
WATERS THROUGH TODAY WITH A BRIEF REPRIEVE TONIGHT. SPEEDS WILL
GENERALLY BE 10-20KT OVER BAY/RIVERS/SOUND AND 15-25KT OVER THE
COASTAL WATERS. SEAS ARE ALSO EXPECTED TO BUILD FROM 2-3FT TO
5-7FT NORTH OF CAPE CHARLES LIGHT...3-4FT SOUTH. ONSHORE FLOW
PERSISTS ON THU WITH AN UPTICK IN WIND SPEEDS TO 10-15KT DURING
THE AFTN/EARLY EVENING. SEAS SUBSIDE BELOW 5FT IN SRN WATERS BY
THU AFTN...WHILE SEAS LINGER AROUND 4-5FT NORTH OF PARRAMORE
ISLAND UNTIL EARLY EVENING. SCA FLAGS FROM FENWICK ISLAND TO CAPE
CHARLES GO INTO EFFECT AT 600 AM THIS MORNING AND WILL MAINTAIN
THAT START TIME BASED ON CURRENT OBSERVATIONS.
THE STALLED FRONT LIFTS NWD AS A WARM FRONT THU NIGHT INTO EARLY FRI
AND WINDS BECOME SLY. SEAS 2-3FT...WAVES 1-2FT. SPEEDS BEGIN TO
INCREASE AROUND SUNRISE FRI MORNING AND WILL CONTINUE TO BE BREEZY
DURING THE DAY AHEAD OF AN APPROACHING COLD FRONT. SPEEDS WILL
AVERAGE 15-20KT (GUSTS UP TO 25KT OVER COASTAL WATERS). SEAS BUILD
TO 3-4FT AND MAY REACH UP TO 5FT NEAR BUOY 44009 BY LATE FRI
AFTN/EARLY EVENING. THE COLD FRONT CROSSES THE WATERS FRI NIGHT. THE
COOLER AIRMASS BEHIND THE FRONT DOES NOT ARRIVE UNTIL DURING THE DAY
ON SAT. A DAYTIME ARRIVAL OF COOLER AIR WILL DECREASE CHANCES FOR
POST-FRONTAL SCA WINDS. EXPECT NW WINDS ON SAT AOB 15KT...DECREASING
SAT NIGHT AS HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST AND
SETTLES OVER THE WATERS ON SUN/SUN NIGHT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 2 PM EDT
THURSDAY FOR ANZ652-654.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ650.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MAS/MAM
LONG TERM...ALB
AVIATION...BMD
MARINE...ALB/BMD
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
420 AM EDT WED APR 8 2015
.SYNOPSIS...
A BACKDOOR COLD FRONT WILL DROP SOUTH ACROSS THE LOCAL AREA EARLY
TODAY THROUGH TONIGHT. THE FRONT THEN WEAKENS AND LIFTS BACK
NORTH AS A WARM FRONT ON THURSDAY. ANOTHER COLD FRONT CROSSES THE
REGION LATE FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 405 AM EDT...
LATEST SURFACE ANALYSIS FEATURES SFC LOW PRESSURE IN PLACE OVER
THE CENTRAL HIGH PLAINS, WITH A QUASI- STATIONARY FRONTAL BOUNDARY
DRAPED ACROSS THE MID MS VLY OVER INTO THE OHIO VLY AND THE LWR
EASTERN SHORE. NOTING SOME POCKETS OF SHRAS ACROSS THE AREA ON
REGIONAL RADAR MOSAIC IN ASSOCIATION WITH A FEW WEAK DISTURBANCES.
NOTING A FEW SCT SHRAS PUSHING ACROSS THE LWR EASTERN SHORE THIS
MORNING ALONG THE FRONT. MEANWHILE, TO THE WEST A MORE SUBSTANTIAL
AREA OF SHRAS IN ASSOCIATION WITH DECAYING CONVECTIVE COMPLEX THAT
ROLLED ACROSS THE OHIO RVR VALLEY LAST NIGHT. THIS ACTIVITY IS
PUSHING FROM E WV/WESTERN VA OVER TO THE PIEDMONT THIS MORNING IN
THE FORM OF SOME LIGHT TO MODERATE RAIN SHRAS. LATEST HRRR AND TO
A LESSER EXTENT THE 00Z NAM HAVE BEST HANDLED THIS FEATURE THUS
FAR... AND HAVE THEREFORE LEANED THE FORECAST IN THIS DIRECTION
FOR THE NEAR TERM. HAVE GONE WITH A BRIEF PERIOD OF LIKELY SHRAS
THIS MORNING MAINLY IN THE WARM SECTOR... WITH THE BEST RAIN
CHANCES FROM THE EASTERN PIEDMONT/WEST OF RIC METRO EARLY THIS
MORNING...REACHING THE I-95 CORRIDOR BY DAWN AND EVENTUALLY SOUTH
CENTRAL VA/HAMPTON ROADS BY MID TO LATE MORNING. EXPECT LESS SHRA
ACTIVITY THIS AFTN BEHIND DEPARTING SHORTWAVE AND HV THEREFORE CUT
BACK ON POP FOR THE AFTN. EXPECT THE FRONT TO THE NORTH TO DROP
SOUTH- SOUTHEAST IN BACKDOOR FASHION THIS MORNING, BRINGING ABOUT
A WIND SHIFT TO THE NE FROM MIDDAY INTO THE AFTN. TEMPERATURES
WILL STABILIZE TO FALL SLIGHTLY ACROSS THE NORTHERN NECK/EASTERN
SHORE, AS TEMPERATURES WARM INTO THE LOW TO MID 70S IN THE WARM
SECTOR OVER INLAND SECTIONS ALONG AND SOUTH OF THE VA/NC BORDER.
FARTHER NORTH, LOOK FOR HIGHS IN THE U40S NEAR OCEAN CITY...LOW TO
MID 50S OVER THE NORTHERN HALF OF THE AREA.
EXPECT ANOTHER ROUND OF CONVECTION BY EARLY EVENING AS NEXT
DISTURBANCE NOW OVER THE MID MO VLY TRANSLATES EAST. WILL INCREASE
POP AGAIN BRIEFLY TONIGHT AS DISTURBANCE MOVES ALONG THE FRONT,
IN PLACE ALONG OR JUST SOUTH OF THE VA/NC BORDER THIS EVENING.
RAIN CHANCES DROP OFF AGAIN TONIGHT BEHIND THIS FEATURE
OVERNIGHT. COOLER TONIGHT IN MOIST NE FLOW BEHIND THE FRONT, WITH
LOWS IN THE 40S NE TO MID 50S SW SECTIONS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
THE FRONT WILL WEAKEN AND SLOWLY PUSH BACK NWD AS A WARM FRONT ON
THU...WITH HIGHS RANGING FM THE 50S LWR ERN SHORE TO THE 70S IN
THE WARM SECTOR ACROSS FAR SRN/WRN AREAS.
NEXT COLD FRONT APPROACHES FM THE W ON FRI. CHANCES OF
SHRAS/TSTMS INCREASE FM W TO E THRU THE DAY...WITH THE BEST CHANCE
(60% POPS) IN THE AFTN/EVE HRS. SOME TSTMS MAY HAVE STRONG GUSTY
WINDS AND HEAVY RAIN...MAINTAINED MENTION IN THE HWO. TEMPS WILL
BE MUCH HIGHER THAN PREVIOUS DAYS WITH THE REGION IN THE WARM
SECTOR...HIGHS IN THE MID 70S TO MID 80S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
SFC CDFNT TO PUSH OFF THE CST AFT MDNGT FRI NGT...TO BE FOLLOWED
BY HI PRES FM THE WNW BUILDING OVR THE RGN THIS WKND. CONTG HI
CHC/LIKELY POPS FRI EVE...THEN TAPERING OFF W-E THROUGH LT FRI
NGT/EARLY SAT MRNG. XPCG CLRG ON SAT AS DRYING AIR FM THE WNW
SPREADS OVR THE RGN. THE HIGH MOVES OFF THE CST BY EARLY NEXT
WK...RESULTING IN WNDS BECOMING SSW...AND MOISTURE GRADUALLY
INCRSG. LO TEMPS FRI NGT FM THE M50S NW TO ARND 60F SE. HI TEMPS
SAT IN THE L/M60S AT THE CST...TO L70S INLAND. LO TEMPS SAT NGT FM
THE M40S NW TO L50S SE. HI TEMPS SUN NR 60F AT THE CST...TO 65 TO
70F ELSW. HI TEMPS MON/TUE FM THE M60S TO M70S.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
A BACKDOOR COLD FRONT IS DROPPING SOUTH INTO FAR NERN COUNTIES OF
THE FA EARLY THIS MORNING. VARIABLE BR WITH VISIBILITIES RANGING
FROM 1-5SM ACROSS THE REGION...WITH POCKETS OF FG WITH
VISIBILITIES FROM 1/4-1/2SM. NORTH OF THE FRONTAL BOUNDARY...WINDS
ARE NE AROUND 10-15KT. SOUTH OF THE BOUNDARY...WINDS ARE LIGHT
FROM THE SOUTH. AS THE FRONT SAGS SWD TODAY...EXPECT SIMILAR WIND
SHIFTS AND SPEEDS AS THE DAY PROGRESSES. MEANWHILE...A DECENT
SWATH OF RAIN SHOWERS ARE PUSHING WWD INTO THE ERN PIEDMONT AS OF
08/0800Z. RAIN WILL CONTINUE TO PUSH EWD ACROSS THE REGION
TODAY...BECOMING MORE FOCUSED ACROSS THE SOUTH WHERE THE FRONTAL
BOUNDARY IS LOCATED. EXPECT A COMBINATION OF MVFR/IFR CIGS IN RAIN
SHOWERS TODAY. PRECIP COMES TO AN END BY MID TO LATE
EVENING...WITH AREAS OF FOG EXPECTED TO DEVELOP QUICKLY OVERNIGHT.
CIGS ARE EXPECTED TO BE AROUND 400FT AGL WITH VARIABLE
VISIBILITIES IN IFR/MVFR CATEGORIES. THE BACKDOOR FRONT STALLS
ACROSS THE CAROLINAS WED NIGHT/THU AND CONDITIONS SHOULD BE SLOW
TO IMPROVE THU MORNING. THE FRONT LIFTS NWD THROUGH THE REGION THU
NIGHT/EARLY FRI MORNING. BREEZY CONDITIONS ANTICIPATED FRI AHEAD
OF AN APPROACHING COLD FRONT WHICH IS EXPECTED TO CROSS THE REGION
FRI EVENING. HIGH PRESSURE RETURNS TO THE REGION SAT/SUN.
&&
.MARINE...
SFC LOW PRESSURE WILL MOVE ACROSS THE WATERS INVOF A BACKDOOR COLD
FRONT...WHICH IS DROPPING DOWN ACROSS THE VA EASTERN SHORE AS OF
300 AM THIS MORNING. WINDS ARE GENERALLY LIGHT FROM THE S-SW SOUTH
OF THE FRONT...WITH BREEZY N-NE WINDS 10-20KT WITH GUSTS AROUND
25KT NORTH OF THE FRONT. AM ALREADY SEEING AN INCREASE IN WIND
SPEEDS IN CHES BAY NORTH OF TANGIER ISLAND AND ALONG THE ATLANTIC
COAST FROM FENWICK ISLAND TO PARRAMORE ISLAND. THE FRONT WILL
GRADUALLY DROP SWD THROUGH THE REST OF TODAY...STALLING ACROSS THE
CAROLINAS TONIGHT INTO THU. EXPECT NNE WINDS TO INCREASE OVER THE
WATERS THROUGH TODAY WITH A BRIEF REPRIEVE TONIGHT. SPEEDS WILL
GENERALLY BE 10-20KT OVER BAY/RIVERS/SOUND AND 15-25KT OVER THE
COASTAL WATERS. SEAS ARE ALSO EXPECTED TO BUILD FROM 2-3FT TO
5-7FT NORTH OF CAPE CHARLES LIGHT...3-4FT SOUTH. ONSHORE FLOW
PERSISTS ON THU WITH AN UPTICK IN WIND SPEEDS TO 10-15KT DURING
THE AFTN/EARLY EVENING. SEAS SUBSIDE BELOW 5FT IN SRN WATERS BY
THU AFTN...WHILE SEAS LINGER AROUND 4-5FT NORTH OF PARRAMORE
ISLAND UNTIL EARLY EVENING. SCA FLAGS FROM FENWICK ISLAND TO CAPE
CHARLES GO INTO EFFECT AT 600 AM THIS MORNING AND WILL MAINTAIN
THAT START TIME BASED ON CURRENT OBSERVATIONS.
THE STALLED FRONT LIFTS NWD AS A WARM FRONT THU NIGHT INTO EARLY FRI
AND WINDS BECOME SLY. SEAS 2-3FT...WAVES 1-2FT. SPEEDS BEGIN TO
INCREASE AROUND SUNRISE FRI MORNING AND WILL CONTINUE TO BE BREEZY
DURING THE DAY AHEAD OF AN APPROACHING COLD FRONT. SPEEDS WILL
AVERAGE 15-20KT (GUSTS UP TO 25KT OVER COASTAL WATERS). SEAS BUILD
TO 3-4FT AND MAY REACH UP TO 5FT NEAR BUOY 44009 BY LATE FRI
AFTN/EARLY EVENING. THE COLD FRONT CROSSES THE WATERS FRI NIGHT. THE
COOLER AIRMASS BEHIND THE FRONT DOES NOT ARRIVE UNTIL DURING THE DAY
ON SAT. A DAYTIME ARRIVAL OF COOLER AIR WILL DECREASE CHANCES FOR
POST-FRONTAL SCA WINDS. EXPECT NW WINDS ON SAT AOB 15KT...DECREASING
SAT NIGHT AS HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST AND
SETTLES OVER THE WATERS ON SUN/SUN NIGHT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 2 PM EDT
THURSDAY FOR ANZ652-654.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ650.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MAS/MAM
LONG TERM...ALB
AVIATION...BMD
MARINE...BMD
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
405 AM EDT WED APR 8 2015
.SYNOPSIS...
A BACKDOOR COLD FRONT WILL DROP SOUTH ACROSS THE LOCAL AREA EARLY
TODAY THROUGH TONIGHT. THE FRONT THEN WEAKENS AND LIFTS BACK
NORTH AS A WARM FRONT ON THURSDAY. ANOTHER COLD FRONT CROSSES THE
REGION LATE FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 405 AM EDT...
LATEST SURFACE ANALYSIS FEATURES SFC LOW PRESSURE IN PLACE OVER
THE CENTRAL HIGH PLAINS, WITH A QUASI- STATIONARY FRONTAL BOUNDARY
DRAPED ACROSS THE MID MS VLY OVER INTO THE OHIO VLY AND THE LWR
EASTERN SHORE. NOTING SOME POCKETS OF SHRAS ACROSS THE AREA ON
REGIONAL RADAR MOSAIC IN ASSOCIATION WITH A FEW WEAK DISTURBANCES.
NOTING A FEW SCT SHRAS PUSHING ACROSS THE LWR EASTERN SHORE THIS
MORNING ALONG THE FRONT. MEANWHILE, TO THE WEST A MORE SUBSTANTIAL
AREA OF SHRAS IN ASSOCIATION WITH DECAYING CONVECTIVE COMPLEX THAT
ROLLED ACROSS THE OHIO RVR VALLEY LAST NIGHT. THIS ACTIVITY IS
PUSHING FROM E WV/WESTERN VA OVER TO THE PIEDMONT THIS MORNING IN
THE FORM OF SOME LIGHT TO MODERATE RAIN SHRAS. LATEST HRRR AND TO
A LESSER EXTENT THE 00Z NAM HAVE BEST HANDLED THIS FEATURE THUS
FAR... AND HAVE THEREFORE LEANED THE FORECAST IN THIS DIRECTION
FOR THE NEAR TERM. HAVE GONE WITH A BRIEF PERIOD OF LIKELY SHRAS
THIS MORNING MAINLY IN THE WARM SECTOR... WITH THE BEST RAIN
CHANCES FROM THE EASTERN PIEDMONT/WEST OF RIC METRO EARLY THIS
MORNING...REACHING THE I-95 CORRIDOR BY DAWN AND EVENTUALLY SOUTH
CENTRAL VA/HAMPTON ROADS BY MID TO LATE MORNING. EXPECT LESS SHRA
ACTIVITY THIS AFTN BEHIND DEPARTING SHORTWAVE AND HV THEREFORE CUT
BACK ON POP FOR THE AFTN. EXPECT THE FRONT TO THE NORTH TO DROP
SOUTH- SOUTHEAST IN BACKDOOR FASHION THIS MORNING, BRINGING ABOUT
A WIND SHIFT TO THE NE FROM MIDDAY INTO THE AFTN. TEMPERATURES
WILL STABILIZE TO FALL SLIGHTLY ACROSS THE NORTHERN NECK/EASTERN
SHORE, AS TEMPERATURES WARM INTO THE LOW TO MID 70S IN THE WARM
SECTOR OVER INLAND SECTIONS ALONG AND SOUTH OF THE VA/NC BORDER.
FARTHER NORTH, LOOK FOR HIGHS IN THE U40S NEAR OCEAN CITY...LOW TO
MID 50S OVER THE NORTHERN HALF OF THE AREA.
EXPECT ANOTHER ROUND OF CONVECTION BY EARLY EVENING AS NEXT
DISTURBANCE NOW OVER THE MID MO VLY TRANSLATES EAST. WILL INCREASE
POP AGAIN BRIEFLY TONIGHT AS DISTURBANCE MOVES ALONG THE FRONT,
IN PLACE ALONG OR JUST SOUTH OF THE VA/NC BORDER THIS EVENING.
RAIN CHANCES DROP OFF AGAIN TONIGHT BEHIND THIS FEATURE
OVERNIGHT. COOLER TONIGHT IN MOIST NE FLOW BEHIND THE FRONT, WITH
LOWS IN THE 40S NE TO MID 50S SW SECTIONS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
THE FRONT WILL WEAKEN AND SLOWLY PUSH BACK NWD AS A WARM FRONT ON
THU...WITH HIGHS RANGING FM THE 50S LWR ERN SHORE TO THE 70S IN
THE WARM SECTOR ACROSS FAR SRN/WRN AREAS.
NEXT COLD FRONT APPROACHES FM THE W ON FRI. CHANCES OF
SHRAS/TSTMS INCREASE FM W TO E THRU THE DAY...WITH THE BEST CHANCE
(60% POPS) IN THE AFTN/EVE HRS. SOME TSTMS MAY HAVE STRONG GUSTY
WINDS AND HEAVY RAIN...MAINTAINED MENTION IN THE HWO. TEMPS WILL
BE MUCH HIGHER THAN PREVIOUS DAYS WITH THE REGION IN THE WARM
SECTOR...HIGHS IN THE MID 70S TO MID 80S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
SFC CDFNT TO PUSH OFF THE CST AFT MDNGT FRI NGT...TO BE FOLLOWED
BY HI PRES FM THE WNW BUILDING OVR THE RGN THIS WKND. CONTG HI
CHC/LIKELY POPS FRI EVE...THEN TAPERING OFF W-E THROUGH LT FRI
NGT/EARLY SAT MRNG. XPCG CLRG ON SAT AS DRYING AIR FM THE WNW
SPREADS OVR THE RGN. THE HIGH MOVES OFF THE CST BY EARLY NEXT
WK...RESULTING IN WNDS BECOMING SSW...AND MOISTURE GRADUALLY
INCRSG. LO TEMPS FRI NGT FM THE M50S NW TO ARND 60F SE. HI TEMPS
SAT IN THE L/M60S AT THE CST...TO L70S INLAND. LO TEMPS SAT NGT FM
THE M40S NW TO L50S SE. HI TEMPS SUN NR 60F AT THE CST...TO 65 TO
70F ELSW. HI TEMPS MON/TUE FM THE M60S TO M70S.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
ALL TAF SITES VFR EARLY THIS EVENING. MOST OF THE RAIN HAS MOVED
OFFSHORE OR DISSIPATED. WINDS ARE MOSTLY FROM THE SE-S AND LESS
THAN 10KT.
A BACKDOOR COLD FRONT IS EXPECTED TO DROP THROUGH THE REGION LATE
TONIGHT/WED MORNING. WINDS WILL SHFT TO THE NE OVERNIGHT AND CIGS
WILL LOWER TO MVFR/IFR CONDS. KRIC/KORF/KPHF SHOULD SEE FRONTAL
PASSAGE IN THE 11Z TO 13Z TIME FRAME...WITH IFR MOVING IN AT OR
JUST AFTER FRONTAL PASSAGE. ATTM...NOT EXPECTING A LOT OF RA/SHRA
ACTIVITY WITH FRONT...ALTHOUGH SOME LIGHT RAIN/DRIZZLE LIKELY TO
OCCUR ANYTIME AFTER 06Z WED.
ONCE FRONT MOVES THROUGH...AN 18-30 HOUR PERIOD OF IFR/LOW MVFR
CEILINGS LIKELY TO PERSIST BEFORE FRONT LIFTS BACK NORTH AS A WARM
FRONT THURSDAY NIGHT/FRIDAY MORNING. COLD FRONT EXPECTED TO MOVE
THROUGH FRIDAY AFTERNOON/NIGHT...BRINGING ADDITIONAL SHWR/TSTM
ACTIVITY.
&&
.MARINE...
SFC LO PRES WILL DEVELOP/MOVE ACRS THE WTRS INVOF BACKDOOR CDFNT
THAT DROPS S ACRS THE WTRS TNGT THROUGH WED...SWITCHING WNDS TO
THE N-NE. XPCG NNE WINDS TO INCREASE OVER THE WATER VERY LT
TNGT/ERY WED FAR NRN OCN WTRS...THEN CONT ELSW DURG WED. SPEEDS
OF 10-20 KT OVER THE ERN VA RIVERS/BAY/SOUND AND 15 TO 25 KT OVER
THE COASTAL WATERS. SEAS ALSO BUILD TO 5-7 FT NORTH OF CAPE
CHARLES LIGHT...3-4 FT SOUTH. ONSHORE FLOW PERSISTS THU WITH SEAS
IN THE NRN WATERS HOVERING AROUND 5-6 FT...COULD BE A PD OF NR 5
FT SRN OCN WTRS WED NGT/THU AS WELL. FRONT LIFTS BACK NORTH OF
THE WATERS THU NGT-FRI WITH WNDS BECOMING SSW. COLD FRONT CROSSES
THE WATERS FRI NIGHT. STRONGEST CAA EXPECTED TO REMAIN N OF THE
REGION POST CDFNT (INTO SAT)...SO DO NOT ANTICIPATE SCA
CONDITIONS ATTM.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 2 PM EDT
THURSDAY FOR ANZ652-654.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ650.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MAS
LONG TERM...ALB
AVIATION...JEF/WRS
MARINE...ALB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
436 AM EDT WED APR 8 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 448 PM EDT TUE APR 7 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE CONFLUENT FLOW
THAT HAS BEEN ACROSS THE UPPER GREAT LAKES IS SHIFTING E AND NE AS
THE NRN STREAM TROF OVER ERN CANADA IS SLOWLY LIFTING OUT AND SRN
BRANCH RIDGE OVER THE PLAINS DOWNSTREAM OF TROF ALONG THE W COAST IS
GRADUALLY BUILDING NE AND E. SFC HIGH PRES SUPPORTED BY THE
CONFLUENT FLOW ALOFT RIDGES W-E ACROSS NRN ONTARIO INTO SRN QUEBEC.
ALTHOUGH THERE HAVE BEEN SOME MID-LEVEL RADAR RETURNS ACROSS THE
FCST AREA...ESPECIALLY EARLIER TODAY...THE VERY DRY AIR AT THE LOWER
LEVELS EMANATING FROM THE HIGH PRES RIDGE HAS RESULTED IN DRY
WEATHER ACROSS THE FCST AREA TODAY. IN FACT...THE KEWEENAW AND ERN
UPPER MI HAVE ENJOYED MOSTLY SUNNY SKIES FOR A GOOD PART OF THE DAY.
TO THE S...WARM FRONT/STATIONARY FRONT EXTENDS FROM KS ACROSS CNTRL
IL INTO NRN OHIO. TO THE W AND SW...A WELL-DEFINED SHORTWAVE IS
TRACKING ENE ACROSS SE SASKATCHEWAN WHILE WEAKER WAVES ARE MOVING
ACROSS WY/CO AND OUT ACROSS THE PLAINS. THESE FEATURES WILL PLAY A
ROLE IN A CHALLENGING FCST HERE TONIGHT/WED.
INITIALLY...EXPECT DRY WEATHER TO PREVAIL THIS EVENING UNDER A
CONTINUED FEED OF DRY LOW-LEVEL AIR FROM THE E AND NE. SFC DWPTS AS
OF 19Z WERE STILL MOSTLY IN THE 5-10F RANGE ALONG THE MI/WI
BORDER...INDICATING THE DRYNESS THAT IS STILL AT THE SFC...AND
LATEST RAP FCST SOUNDINGS SHOW THE DRY AIR IN THE LOWER LEVELS
HANGING ON DURING THE EVENING. LATER TONIGHT INTO WED...FOCUS SHIFTS
TO THE AFORMENTIONED SHORTWAVES. THE STRONGER NRN WAVE WILL REACH
NRN ONTARIO EARLY WED MORNING WHILE THE WEAKER SRN WAVES WILL TRACK
INTO THE UPPER LAKES. TRACK OF THE STRONGER NRN WAVE INDICATES ITS
MAIN FORCING WILL PASS N OF HERE...AND THAT IS WHAT MODELS SHOW FOR
PROGRESSION OF DEEP LAYER QVECTORS. FARTHER S...THE WEAKER SRN WAVES
WILL BE ABLE TO INTERACT WITH THE SFC-850MB WARM FRONT AND
CONSIDERABLY MORE GENEROUS MOISTURE AS WELL AS ABUNDANT INSTABILITY.
LEAD SUBTLE WAVE IS ALREADY GENERATING AN EXPANDING AREA OF
SHRA/TSRA IN SRN MN/NW IA ON THE MUCAPE GRADIENT PER LATEST SPC
MESOANALYSIS. THRU WED MORNING...MODELS SHOW 850MB WARM FRONT NEVER
LIFTING ANY FARTHER N THAN SRN WI. BELIEVE THOSE MODEL SOLUTIONS
WHICH SHOW THE MAIN AREA OF PCPN PASSING S OF UPPER MI TONIGHT/WED
MORNING CLOSER TO 850MB WARM FRONT OR EVEN SFC FRONT ARE PROBABLY ON
THE RIGHT TRACK. THIS WOULD BE ESPECIALLY TRUE IF SIGNIFICANT
CONVECTION ENDS UP DEVELOPING/EXPANDING NEAR THE WARM FRONT...A
DEFINITE POSSIBILITY GIVEN THE MAGNITUDE OF INSTABILITY THAT WILL
REMAIN MUCH FARTHER S. WHILE THE SHRA/TSRA MOVING ACROSS SRN MN INTO
SW WI IS A CONCERN...THAT PCPN SHOULD TEND TO PEEL MORE EASTWARD
WITH TIME AS THE SHRA/TSRA SHOULDN`T BREAK TOO FAR AWAY FROM THE
INSTABILITY GRADIENT WHICH WILL REMAIN WELL S OF HERE. SO...THE GFS
WHICH CARRIES 1/3RD TO 1/2 INCH OF PCPN INTO SCNTRL UPPER MI
CERTAINLY LOOKS LIKE AN OUTLIER COMPARED TO THE OTHER MODELS WHICH
ARE MUCH LIGHTER ON PCPN. NONETHELESS...TAIL END OF NRN SHORTWAVE
WILL PROVIDE SUPPORT FOR AN EXTENSION OF PCPN N AND NW FROM HEAVIER
PCPN TO THE S. UTILIZING A CONSENSUS APPROACH FOR POPS...WEIGHTED
TOWARD HIGH RES GUIDANCE...WILL SPREAD A BAND OF CHC POPS ACROSS THE
AREA OVERNIGHT/WED MORNING WITH TREND TOWARD LOWER POPS OVER THE
NRN/ERN FCST AREA. WILL INCLUDE LIKELY POPS INTO MENOMINEE COUNTY.
PCPN WILL END (OR DIMINISH TO DZ BEFORE ENDING) FROM SW TO NE MID
MORNING THRU EARLY AFTN.
PTYPE IS A CHALLENGE. INITIAL DRY AIR MASS/EVAPORATIVE COOLING
SHOULD MAKE SNOW THE MORE DOMINANT PTYPE. HOWEVER...PERUSAL OF MODEL
FCST SOUNDINGS SHOW TEMP PROFILE HOVERING AROUND 0C OVER A FAIRLY
SIGNIFICANT DEPTH...INDICATING A VARIETY OF PTYPES WILL BE POSSIBLE
WITH ONLY VERY SLIGHT CHANGES TO THE TEMP PROFILE. SO...FCST WILL
REFLECT A WINTRY MIX OF SN/IP/FZRA/RA AT MOST LOCATIONS...THOUGH
MAINLY SN IS MORE LIKELY IN HIGHER TERRAIN AREAS. FOR PCPN
AMOUNTS...EXPECT TOTAL WATER EQUIVALENT PCPN OF ROUGHLY 0.05 TO 0.15
INCHES....GREATEST SCNTRL. SNOW AMOUNTS SHOULD BE UNDER 1 INCH...AND
WHERE FRZA OCCURS...A COUPLE OF HUNDREDTHS ARE POSSIBLE. AT THIS
POINT...ADVY HEADLINES ARE NOT WARRANTED. IF FOR SOME REASON TRENDS
THIS EVENING POINT TOWARD HEAVIER PCPN REACHING THE AREA...HEADLINES
WILL NEED TO BE RECONSIDERED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 431 AM EDT WED APR 8 2015
MAIN FCST CONCERN IN THE LONGER TERM PERIOD WL BE ON POPS/PTYPE
FOR THE THU INTO FRI TIME IN ASSOCIATION WITH LO PRES THAT IS FCST
TO MOVE NE FM THE PLAINS AND THRU THE GREAT LKS. THE EXACT DETAILS
ON THIS FAIRLY COMPLEX SCENARIO...INCLUDING LO INTENSITY AND
TRACK...WL DEPEND ON THE PHASING/INTERACTION BTWN NRN AND SRN BRANCH
SHRTWVS AND THE EVENTUAL INTENSITY OF THE SRN BRANCH DISTURBANCE
THAT IS NOW OVER THE SW CONUS. FORTUNATELY...THE LATEST ROUND OF
EXPLICIT MODEL FCSTS IS BEGINNING TO COME INTO BETTER AGREEMENT ON
THE FCST DETAILS. HI PRES AND TRANQUIL WX WL RETURN FOR SAT.
THU/THU NGT...THE UPR FLOW ON THU WL FEATURE A NRN BRANCH SHRTWV
DIGGING SE INTO NW ONTARIO WHILE SRN BRANCH SHRTWV THAT IS CURRENTLY
OVER THE SW CONUS WL BE LIFTING NEWD TOWARD THE UPR MIDWEST ON THE
NW FLANK OF UPR RDG OVER THE SE CONSU. ON THU NGT...SOME OF THE
MODELS SHOW MORE PHASING BTWN THESE WAVES...WITH A DEEPER FARTHER W
SFC LO TRACK AS FAR W AS UPR MI. IN GENERAL...RECENT ECMWF RUNS HAVE
FAVORED THE LESS PHASED/WEAKER SRN BRANCH DISTURANCE AND WEAKER SFC
LO SCENARIO...WHILE THE CNDN MODEL AND ESPECIALLY THE GFS RUNS HAVE
SIDED WITH MORE PHASING AND A DEEPER SRN BRANCH SHRTWV/FARTHER W SFC
LO TRACK. ALTHOUGH CHALLENGING A CONSISTENT ECMWF FCST IS RISKY...
THE INTENSITY OF THE DISTURBANCE NOW OVER THE SW CONUS WOULD
SEEM TO FAVOR A DEEPER AND FARTHER W SFC LO TRACK THAN SHOWN BY THE
ECMWF RUNS...EVEN IF THERE IS NOT A LOT OF PHASING WITH THE NRN
BRANCH SHRTWV. IN FACT...THE 00Z NAM DOES SUPPORT A 993MB SFC LO
TRACKING ACROSS NW LOWER MI AT 06Z FRI TO THE E OF SLIGHTLY
NEGATIVELY TILTED SRN BRANCH DISTURBANCE EVEN WITHOUT SGNFT PHASING
WITH THE NRN SHRTWV. THE 00Z GFS REMAINS A BIT DEEPER WITH A
990MB SFC LO AT 06Z...BUT ITS LO TRACK IS NOW ONLY A BIT FARTHER W
THAN SHOWN BY THE NAM. GIVEN THIS FAIRLY GOOD AGREEMENT AND
PREFERENCE FOR A STRONGER SRN BRANCH SHRTWV...WL RELY ON THE 00Z
NAM/GFS FCSTS FOR FCST DETAILS. QUICK LOOK AT THE 00Z ECMWF
SHOWS A TREND IN THIS DIRECTION...INCRSG CONFIDENCE IN THE
FCST. THESE MODELS SHOW SOME GENERALLY LGT PCPN DVLPG ON THU MRNG
WITH LARGER SCALE ISENTROPIC ASCENT TO THE NE OF THE APRCHG SRN
BRANCH SHRTWV/SFC LO. EXCEPT OVER THE FAR NW CWA OVER LK SUP...THIS
PCPN WL BE LIQUID AS H85 TEMPS ARE FCST TO BE HIER THAN 0C. BUT
LINGERING NEAR SFC COLD AIR/HI STABILITY SHOWN ON FCST SDNGS WL
SUPPORT GOING FCST OF FREEZING RA OVER MUCH OF THE CWA BEFORE SOME
WARMING ALLOWS TEMPS TO RISE ABOVE 32 AT MOST PLACES AND CHANGES THE
PCPN TO PLAIN RA WITH SLOW INFLUX OF WARMER NEAR SFC AIR. GIVEN THE
MOISTENING SHALLOW STABLE LYR...ADDED SOME PATCHY FOG FOR MOST OF
THE CWA. AS THE DAY WEARS ON AND THE SRN BRANCH SHRTWV APRCHS...THE
ARRIVAL OF MORE VIGOROUS DEEP LYR QVECTOR CNVGC/UPR DVGC/AXIS OF MID
LVL FGEN THAT WL SUPPORT SHARPENING H85 THERMAL GRADIENT WL SUPPORT
HIER POPS/QPF. OVER THE W...THE FCST THERMAL FIELDS WITH THIS MORE
VIGOROUS UVV INDICATE A MIX WITH SN TOWARD 00Z FRI. DESPITE THE
DIFFERENCES ON THE PHASING BTWN BRANCHES...ALL THE MODELS ARE IN
FAIRLY GOOD AGREEMENT SHOWING SOME ENHANCED UPR DVGC OVER THE CWA ON
THU NGT IN COUPLED UPR JET STRUCTURE...RRQ OF NRN BRANCH JET CORE
NEAR JAMES BAY AND LEFT EXIT OF SRN BRANCH JET STREAK MOVING TOWARD
LOWER MI. THIS SHARPER UPR DVGC SHOULD ENHANCE UVV/DYNAMIC COOLING
AND LEAD TO A CHANGE TO MAINLY SN W-E. ALTHOUGHTHERE ARE SOME SUBTLE
DIFFERENCES EVEN AMONG THE NAM AND GFS...LOOKS LIKE THE W AND CENTRAL
PORTIONS OF CWA HAVE THE BEST CHC FOR SEEING SOME HEADLINE SN AMOUNTS
GIVEN TRACK OF SHRTWV AND PLACEMENT ON CYC SIDE OF ACCOMPANYING H7 LO
TRACK/HINT OF A TROWAL FEATURE UNDER AXIS OF HIER H7 SPECIFIC
HUMIDITY AOA 4 G/KG. AT THIS POINT...DECIDED TO ISSUE AN SPS TO COVER
THE COMPLEX WINTER WX/MIXED PCPN EXPECTED THIS MRNG AND THEN AGAIN
LATE TNGT THRU THU NGT.
FRI...AS SRN SHRTWV LIFTS TO THE NE AND LINGERING DEEP LYR QVECTOR
CNVGC EXITS TO THE NE IN THE MRNG...EXPECT PCPN TO DIMINISH...
ESPECIALLY IN THE AFTN WITH APRCH OF SFC HI PRES AND WEAKENING CYC
NW FLOW. BUT PASSING NRN BRANCH SHRTWV/AXIS OF SOME QVECTOR CNVGC WL
MAINTAIN AT LEAST POPS. ANY LINGERING SN SHOWERS WL LIKELY MIX WITH
RA IN THE PRESENCE OF DAYTIME HEATING.
FRI NGT THRU SAT NGT...HI PRES IS FCST TO FOLLOW INTO THE WRN LKS ON
FRI NGT AND END ANY LINGERING PCPN. AS THE RDG AXIS/DRIER AIRMASS
WITH PWAT AOB 0.25 INCH TRACK OVER THE UPR LKS ON SAT...EXPECT
MOSUNNY AND WARMER WX AS H85 TEMPS REBOUND TO ARND 4C. MAX TEMPS
SHOULD RISE WELL INTO THE 50S AWAY FM LK MODERATION. A WAA REGIME WL
TAKE OVER ON SAT NGT AND BRING A RETURN OF AT LEAST SOME MID CLDS
AS THE SFC HI PRES SHIFTS TO THE E AND A STRONG SW WIND DEVELOPS.
RECENT GFS RUNS HAVE GENERATED SOME LGT PCPN AS PWAT REBOUNDS CLOSE
TO 0.75 INCH. BUT SINCE MOST OF THE GUIDANCE SHOWS A DRY FCST...
WENT NO HIER THAN SCHC POPS.
SUN THRU TUE...A SHRTWV TRACKING THRU CENTRAL CANADA WL DRAG A
COLD FNT THRU THE UPR LKS LATE THIS WEEKEND/EARLY NEXT WEEK. THE
AIRMASS IN PLACE WL BE WARM ENUF FOR ALL LIQUID PCPN DURING THIS
FROPA...WHICH WL BE FOLLOWED BY A MARITIME POLAR PACIFIC AIRMASS. SO
TEMPS SHOULD AVERAGE AOA NORMAL ON SUN THRU TUE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 129 AM EDT WED APR 8 2015
AS A DISTURBANCE MOVES INTO THE GREAT LAKES TONIGHT...LIGHT PCPN
WILL PROBABLY AFFECT ALL TERMINALS LATE TONIGHT INTO WED MORNING.
ALONG WITH -SN...THERE MAY BE SOME -RA/-FZRA/PL...THOUGH CONFIDENCE
IS QUITE LOW ON PTYPE. EXPECT MVFR CONDITIONS TO EVENTUALLY
DEVELOP...AND LINGER THRU THE END OF THE FCST PERIOD...ALTHOUGH PCPN
SHOULD GENERALLY END BY LATE WED MORNING/WED AFTERNOON IN THE WAKE
OF THE DISTURBANCE. THERE IS A CHANCE FOR IFR CONDITIONS TO DEVELOP
AT KSAW WED EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 448 PM EDT TUE APR 7 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HIGH PRES THAT WILL MOVE
FROM NRN ONTARIO INTO QUEBEC THRU WED AND A WARM FRONT THAT
WILL REMAIN TO THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO
NE WINDS WILL PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE
STRONGEST OVER WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE
ISLANDS AND MN NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE
THE WINDS. IN THAT AREA...EXPECT NE WINDS OF 20-30KT TONIGHT...WITH
SOME GALE FORCE GUSTS TO AROUND 35 KT THRU THE EVENING. E TO NE
WINDS...MOSTLY 10-20KT...WILL THEN CONTINUE ON WED AND ON INTO THU
AS LOW PRES LIFTS NE FROM THE CENTRAL PLAINS INTO THE GREAT LAKES
REGION. AT THIS TIME...IT APPEARS THE LOW WILL NOT BE STRONG ENOUGH
TO RESULT IN GALES AS THE LOW APPROACHES AND THEN DEPARTS. WINDS
WILL BACK TO THE N THU AND THEN NW 20-30KT THU NIGHT INTO FRI AS THE
LOW SHIFTS TO THE E AND HIGH PRES BUILDS INTO THE PLAINS. A PERIOD
OF LIGHT WINDS WILL OCCUR FRI NIGHT INTO SAT AS HIGH PRES RIDGE
MOVES ACROSS THE UPPER LAKES. S WINDS WILL THEN BE ON THE INCREASE
TO AT LEAST 10-20KT ON SUN AS THE RIDGE SHIFTS E AND A LOW PRES TROF
MOVES E TO THE UPPER MISSISSIPPI VALLEY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KC
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
129 AM EDT WED APR 8 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 448 PM EDT TUE APR 7 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE CONFLUENT FLOW
THAT HAS BEEN ACROSS THE UPPER GREAT LAKES IS SHIFTING E AND NE AS
THE NRN STREAM TROF OVER ERN CANADA IS SLOWLY LIFTING OUT AND SRN
BRANCH RIDGE OVER THE PLAINS DOWNSTREAM OF TROF ALONG THE W COAST IS
GRADUALLY BUILDING NE AND E. SFC HIGH PRES SUPPORTED BY THE
CONFLUENT FLOW ALOFT RIDGES W-E ACROSS NRN ONTARIO INTO SRN QUEBEC.
ALTHOUGH THERE HAVE BEEN SOME MID-LEVEL RADAR RETURNS ACROSS THE
FCST AREA...ESPECIALLY EARLIER TODAY...THE VERY DRY AIR AT THE LOWER
LEVELS EMANATING FROM THE HIGH PRES RIDGE HAS RESULTED IN DRY
WEATHER ACROSS THE FCST AREA TODAY. IN FACT...THE KEWEENAW AND ERN
UPPER MI HAVE ENJOYED MOSTLY SUNNY SKIES FOR A GOOD PART OF THE DAY.
TO THE S...WARM FRONT/STATIONARY FRONT EXTENDS FROM KS ACROSS CNTRL
IL INTO NRN OHIO. TO THE W AND SW...A WELL-DEFINED SHORTWAVE IS
TRACKING ENE ACROSS SE SASKATCHEWAN WHILE WEAKER WAVES ARE MOVING
ACROSS WY/CO AND OUT ACROSS THE PLAINS. THESE FEATURES WILL PLAY A
ROLE IN A CHALLENGING FCST HERE TONIGHT/WED.
INITIALLY...EXPECT DRY WEATHER TO PREVAIL THIS EVENING UNDER A
CONTINUED FEED OF DRY LOW-LEVEL AIR FROM THE E AND NE. SFC DWPTS AS
OF 19Z WERE STILL MOSTLY IN THE 5-10F RANGE ALONG THE MI/WI
BORDER...INDICATING THE DRYNESS THAT IS STILL AT THE SFC...AND
LATEST RAP FCST SOUNDINGS SHOW THE DRY AIR IN THE LOWER LEVELS
HANGING ON DURING THE EVENING. LATER TONIGHT INTO WED...FOCUS SHIFTS
TO THE AFORMENTIONED SHORTWAVES. THE STRONGER NRN WAVE WILL REACH
NRN ONTARIO EARLY WED MORNING WHILE THE WEAKER SRN WAVES WILL TRACK
INTO THE UPPER LAKES. TRACK OF THE STRONGER NRN WAVE INDICATES ITS
MAIN FORCING WILL PASS N OF HERE...AND THAT IS WHAT MODELS SHOW FOR
PROGRESSION OF DEEP LAYER QVECTORS. FARTHER S...THE WEAKER SRN WAVES
WILL BE ABLE TO INTERACT WITH THE SFC-850MB WARM FRONT AND
CONSIDERABLY MORE GENEROUS MOISTURE AS WELL AS ABUNDANT INSTABILITY.
LEAD SUBTLE WAVE IS ALREADY GENERATING AN EXPANDING AREA OF
SHRA/TSRA IN SRN MN/NW IA ON THE MUCAPE GRADIENT PER LATEST SPC
MESOANALYSIS. THRU WED MORNING...MODELS SHOW 850MB WARM FRONT NEVER
LIFTING ANY FARTHER N THAN SRN WI. BELIEVE THOSE MODEL SOLUTIONS
WHICH SHOW THE MAIN AREA OF PCPN PASSING S OF UPPER MI TONIGHT/WED
MORNING CLOSER TO 850MB WARM FRONT OR EVEN SFC FRONT ARE PROBABLY ON
THE RIGHT TRACK. THIS WOULD BE ESPECIALLY TRUE IF SIGNIFICANT
CONVECTION ENDS UP DEVELOPING/EXPANDING NEAR THE WARM FRONT...A
DEFINITE POSSIBILITY GIVEN THE MAGNITUDE OF INSTABILITY THAT WILL
REMAIN MUCH FARTHER S. WHILE THE SHRA/TSRA MOVING ACROSS SRN MN INTO
SW WI IS A CONCERN...THAT PCPN SHOULD TEND TO PEEL MORE EASTWARD
WITH TIME AS THE SHRA/TSRA SHOULDN`T BREAK TOO FAR AWAY FROM THE
INSTABILITY GRADIENT WHICH WILL REMAIN WELL S OF HERE. SO...THE GFS
WHICH CARRIES 1/3RD TO 1/2 INCH OF PCPN INTO SCNTRL UPPER MI
CERTAINLY LOOKS LIKE AN OUTLIER COMPARED TO THE OTHER MODELS WHICH
ARE MUCH LIGHTER ON PCPN. NONETHELESS...TAIL END OF NRN SHORTWAVE
WILL PROVIDE SUPPORT FOR AN EXTENSION OF PCPN N AND NW FROM HEAVIER
PCPN TO THE S. UTILIZING A CONSENSUS APPROACH FOR POPS...WEIGHTED
TOWARD HIGH RES GUIDANCE...WILL SPREAD A BAND OF CHC POPS ACROSS THE
AREA OVERNIGHT/WED MORNING WITH TREND TOWARD LOWER POPS OVER THE
NRN/ERN FCST AREA. WILL INCLUDE LIKELY POPS INTO MENOMINEE COUNTY.
PCPN WILL END (OR DIMINISH TO DZ BEFORE ENDING) FROM SW TO NE MID
MORNING THRU EARLY AFTN.
PTYPE IS A CHALLENGE. INITIAL DRY AIR MASS/EVAPORATIVE COOLING
SHOULD MAKE SNOW THE MORE DOMINANT PTYPE. HOWEVER...PERUSAL OF MODEL
FCST SOUNDINGS SHOW TEMP PROFILE HOVERING AROUND 0C OVER A FAIRLY
SIGNIFICANT DEPTH...INDICATING A VARIETY OF PTYPES WILL BE POSSIBLE
WITH ONLY VERY SLIGHT CHANGES TO THE TEMP PROFILE. SO...FCST WILL
REFLECT A WINTRY MIX OF SN/IP/FZRA/RA AT MOST LOCATIONS...THOUGH
MAINLY SN IS MORE LIKELY IN HIGHER TERRAIN AREAS. FOR PCPN
AMOUNTS...EXPECT TOTAL WATER EQUIVALENT PCPN OF ROUGHLY 0.05 TO 0.15
INCHES....GREATEST SCNTRL. SNOW AMOUNTS SHOULD BE UNDER 1 INCH...AND
WHERE FRZA OCCURS...A COUPLE OF HUNDREDTHS ARE POSSIBLE. AT THIS
POINT...ADVY HEADLINES ARE NOT WARRANTED. IF FOR SOME REASON TRENDS
THIS EVENING POINT TOWARD HEAVIER PCPN REACHING THE AREA...HEADLINES
WILL NEED TO BE RECONSIDERED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 414 PM EDT TUE APR 7 2015
...AREAS OF FREEZING RAIN/ICING WED NIGHT INTO THU MORNING AND
POSSIBLE HEAVY SNOW THU NIGHT...
LARGE SCALE UPPER LEVEL PATTERN TO START THE LONG TERM FEATURES
TROUGHING FM CENTRAL CANADA SOUTHWEST ACROSS MUCH OF THE WESTERN
CONUS. MAIN SHORTWAVES WITHIN THE TROUGH ON WEDNESDAY NIGHT WILL BE
DIVING SOUTHEAST ACROSS MANITOBA AND STREAMING EASTWARD NEAR THE
FOUR CORNERS REGION. MAIN JET STREAKS WITHIN THE FLOW PATTERN ARE
ORIENTED FM GREAT LAKES TO NEW ENGLAND AND PUSHING ACROSS NORTHERN
MEXICO. AT THE SFC...MAIN CYCLONE IS VCNTY OF CNTRL PLAINS WITH WARM
FRONT EAST ACROSS THE OHIO VALLEY...LIFTING NORTHWARD.
WEAKER LEAD SHORTWAVE/INCREASING DIVERGENCE IN RRQ OF GREAT LAKES
JET/WARM AIR ADVECTION COMBINE TO BRING SOME PRECIP IN THE FORM OF
RAIN SHOWERS OVER THE REGION WEDNESDAY NIGHT INTO THURSDAY MORNING.
GFS/ECMWF/GEM-NH QUICKER IN BRINGING PRECIP OVER AREA...MORE 06Z-12Z
THURSDAY. NAM IS DELAYED...FAVORING 12Z-18Z ON THURSDAY. EITHER WAY
THINK BEST FOCUS FOR RAIN WILL BE ON NOSE OF VEERING H85 JET MAINLY
IMPACTING SOUTH AND EAST CWA. TSRA THAT COULD BE ONGOING ALONG WARM
FRONT COULD FURTHER DISRUPT MOISTURE TRANSPORT INTO UPPER GREAT
LAKES. DUE TO THESE REASONS...LIKE THE IDEA OF LESS QPF SINCE LARGER
SCALE FORCING OVER UPR MICHIGAN IS GENERALLY WEAK. SOUNDINGS AHEAD
OF ANY POTENTIAL PRECIP INDICATE LOW-LEVEL MOISTURE TO H9 BUT DRY
AIR ABOVE THROUGH H5 MUCH OF WEDNESDAY EVENING. SFC WINDS FM EAST
BTWN HIGH PRESSURE RIDGE OVER EASTERN CANADA AND LOW PRESSURE
LIFTING NORTHEAST OVER THE CNTRL PLAINS SUPPORTS BEST CHANCE OF
DZ/FZDZ GENERATED BY UPSLOPE LIFTING OVER HIGHER TERRAIN OF CNTRL
CWA FM MICHIGAMME HIGHLANDS IN BARAGA AND MARQUETTE COUNTY SOUTHWEST
TO MUCH OF IRON AND DICKINSON COUNTIES. EITHER FM THE FZDZ OR
EVENTUALLY ARRIVAL OF LIGHT FZRA...LIGHT ICING IS LIKELY ON
WEDNESDAY NIGHT AS TEMPS WILL STAY AT OR BLO FREEZING MOST OF THE
NIGHT. MAIN CONCERN WOULD BE ON UNTREATED ROADS AND SIDEWALKS BUT
THERE COULD ALSO BE SOME ICING THAT WOULD IMPACT ELEVATED OBJECTS
SUCH AS TREES AND POWERLINES. BEST SHOT OF MOST ICING WILL BE OVER
THE HIGHER TERRAIN AREAS FM BARAGA AND MARQUETTE COUNTY TO IRON AND
DICKINSON COUNTY. DID NOT GET TOO SPECIFIC BTWN DZ/FZDZ AND
RAIN/FZRA. SINCE EVEN IN THE DRIER SCENARIO THERE WOULD BE
MEASURABLE QPF...WENT WITH RAIN/FZRA. WILL KEEP MENTION OF THIS IN
HWO/EHWO...BUT NO HEADLINE ISSUED NOW AS AT THIS POINT SEEMS THAT AT
WORST COULD NEED AN ADVY.
BRIEF LULL POSSIBLE LATER THURSDAY MORNING INTO THURSDAY AFTERNOON
IN BETWEEN SHORTWAVES...LEAD ONE LIFTING ACROSS EASTERN ONTARIO AND
A MUCH STRONGER ONE...EDGING EASTWARD ACROSS CNTRL PLAINS...SET TO
ARRIVE OVER UPR GREAT LAKES THURSDAY NIGHT. SOUNDINGS FOR LATER
THURSDAY INDICATE SOME MOISTURE MAY STICK AROUND ON NORTHERN EDGE OF
SFC LOW LIFTING NORTHEAST FROM THE CNTRL MISSISSIPPI RIVER VALLEY
TOWARD THE WESTERN GREAT LAKES...BUT SEEMS THAT NET FORCING FOR
ANY PRECIP WILL BE MINIMAL. NORTHERN EDGE OF HIGHER MLCAPE AND
INTERSECTION OF LOW-LEVEL AND UPPER LEVEL JET AND H85 THETA-E
AXIS/MAX WARM AIR ADVECTION WOULD KEEP POTENTIAL FOR TSRA STAYING
WELL TO THE SOUTHEAST OF UPR MICHIGAN...LIKELY OVER LOWER GREAT
LAKES OR OHIO VALLEY DEPENDING ON LOCATION OF EMBEDDED WEAKER
CONVECTIVELY DRIVEN SHORTWAVES IN THE WSW FLOW ALOFT. GENERALLY
QUIET WEATHER SHOULD PREVAIL OVER UPPER LAKES THURSDAY AFTN UNTIL
MAIN SHORTWAVE ARRIVES ON THURSDAY NIGHT. MOISTURE ADVECTION INTO
THE AREA MAY CONTINUE TO SPUR ON SOME SHOWERS OR PATCHY RAIN...SO
KEPT CHANCES GOING THROUGH THE PERIOD DESPITE THE MINIMAL FORCING.
MODEL DIFFERENCES WITH STRENGTH AND WESTWARD EXTENT OF THURSDAY
NIGHT SHORTWAVE IS THE MAIN ISSUE ON INTO FRIDAY MORNING. OVERALL...
RECENT NAM/GEM-NH RUNS WERE FARTHER WEST WITH UPPER WAVE AND SFC
LOW WHILE THE 00Z ECMWF WAS MUCH FASTER WITH EASTWARD PUSH OF THE
SHORTWAVE/SFC LOW AND COLD FRONT. GFS REPRESENTED A COMPROMISE
SOLUTION. BY FAR...00Z AND 12Z ECMWF ARE DRIEST...INDICATING LESS
THAN 0.25 INCH OF QPF FM 00Z FRIDAY TO 12Z FRIDAY. MEANWHILE...
NAM/GFS/GEM-NH SHOWED QPF AMOUNTS AT LEAST UP TO 1 INCH...SO QUITE
THE DIFFERENCE.
12Z NAM TRENDED MORE LIKE THE GFS IN TERMS OF LOCATION OF SFC LOW FM
00Z FRIDAY TO 12Z FRIDAY. IN TERMS OF QPF...NAM TRENDED AWAY FM
STRIPE OF 1.5 INCH PLUS AMOUNTS IT WAS SHOWING BUT STILL HAS UP TO
1.25 INCHES OVER PARTS OF WESTERN UPR MICHIGAN. IN FACT...IN THE
VCNTY OF KIWD IS HAS TRENDED MUCH WETTER AS 00Z RUN SHOWED LESS THAN
0.10 INCH...BUT 12Z RUN NOW HAS ALMOST 0.75 INCHES. GUESSING THIS IS
DUE TO MORE PHASING OCCURRING BTWN SHORTWAVE CROSSING THE UPPER
LAKES AND THE APPROACHING WAVE DRIVING SOUTHEAST OVER MANITOBA AND
NORTHERN ONTARIO WHICH IN TURN INCREASES RIGHT ENTRANCE JET STREAK
DIVERGENCE AND ASSOCIATED MID-LEVEL FGEN. 12Z GFS SIMILAR TO
PREVIOUS RUNS WITH SFC LOW POSITION...BUT NOW FOCUSES QPF MORE OVER
WESTERN CWA. GFS SHOWS NOT ONLY MAIN SHORTWAVE LIFTING OVER UPPER
GREAT LAKES AND WAVE OVER NORTHERN ONTARIO...BUT ALSO ANOTHER WAVE
TRYING TO SNEAK IN FM NORTHERN PLAINS. SCENARIO JUST BECOMES MORE
COMPLICATED YET. PTYPE WITH MOST OF THE PRECIP WOULD BE RAIN
CHANGING TO SNOW. POSSIBLE FZRA AS WELL AS ADVECTION OF COLDER LOW-
LEVEL AIRMASS UNDERCUTS LINGERING WARM LAYER ALOFT AT H8-H75. SIGNAL
FOCUSING THAT FAR WEST VCNTY OF KIWD COULD SEE HEAVY SNOW THURSDAY
EVENING INTO THE EARLY MORNING OF FRIDAY DUE TO QUICKER CHANGE FM
RAIN TO SNOW AND GREATER POTENTIAL FOR HEAVIER QPF. WILL CONTINUE TO
MENTION THIS IN THE HWO/EHWO BUT NOT HIT IT UP MUCH HARDER JUST YET
AS UNCERTAINTY REMAINS SINCE THE TYPICALLY BETTER PERFORMING ECMWF
HAS BEEN CONSISTENTLY NOT NEAR AS BULLISH WITH THE SYSTEM AS OTHER
MODELS. AND ITS REALLY NOT EVEN CLOSE.
LOW PRESSURE SYSTEM EXITS ACROSS EASTERN CANADA ON FRIDAY. LINGERING
AIRMASS IS COOL THOUGH AS LOWERED TEMPS WITH THERMAL TROUGH AT H85
REMAINING OVER THE AREA. SHOULD STAY MOSTLY CLOUDY EVEN FARTHER
INLAND WITH POSSIBLE INSTABILITY RAIN/SNOW SHOWERS SINCE THE THERMAL
TROUGH STAYS IN THE VCNTY. HIGH PRESSURE SLIDES OVERHEAD TO START
THE WEEKEND SO LOOKING FOR DRY AND MUCH WARMER CONDITIONS ON
SATURDAY. WINDS BECOME SOUTHWEST AS RIDGE PASSES SATURDAY AFTN.
MIXING TO H9 WOULD SUPPORT HIGHS WELL INTO THE 50S OVER MOST CWA. BY
LATE WEEKEND...UPPER PATTERN SHOWS LARGER TROUGH OVER WESTERN CANADA
AND NORTHWEST CONUS...WITH MORE COMPACT UPPER LOW TRACKING OVER THE
SOUTHWEST CONUS. THERE IS A LOT OF UNCERTAINTY IN HOW THAT SOUTHERN
STREAM WAVE EVOLVES. PREVIOUS ECMWF SHOWED A WRAPPED UP SFC LOW OVER
THE CNTRL PLAINS...WHILE THE 12Z ECMWF SHOWS NOTHING OF THE SORT.
ESSENTIALLY...SEE NO REASON TO STRAY FM CONSENSUS BEYOND THE LATE
WEEK SYSTEM GIVEN THE BIGGER UNCERTAINTY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 129 AM EDT WED APR 8 2015
AS A DISTURBANCE MOVES INTO THE GREAT LAKES TONIGHT...LIGHT PCPN
WILL PROBABLY AFFECT ALL TERMINALS LATE TONIGHT INTO WED MORNING.
ALONG WITH -SN...THERE MAY BE SOME -RA/-FZRA/PL...THOUGH CONFIDENCE
IS QUITE LOW ON PTYPE. EXPECT MVFR CONDITIONS TO EVENTUALLY
DEVELOP...AND LINGER THRU THE END OF THE FCST PERIOD...ALTHOUGH PCPN
SHOULD GENERALLY END BY LATE WED MORNING/WED AFTERNOON IN THE WAKE
OF THE DISTURBANCE. THERE IS A CHANCE FOR IFR CONDITIONS TO DEVELOP
AT KSAW WED EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 448 PM EDT TUE APR 7 2015
WITH LAKE SUPERIOR SITUATED BETWEEN HIGH PRES THAT WILL MOVE
FROM NRN ONTARIO INTO QUEBEC THRU WED AND A WARM FRONT THAT
WILL REMAIN TO THE S AND SW ACROSS THE PLAINS TO OHIO VALLEY...E TO
NE WINDS WILL PERSIST. TYPICAL FOR E TO NE WINDS...WINDS WILL BE
STRONGEST OVER WRN LAKE SUPERIOR...IN PARTICULAR BTWN THE APOSTLE
ISLANDS AND MN NSHORE WHERE FUNNELING/COASTAL CONVERGENCE ENHANCE
THE WINDS. IN THAT AREA...EXPECT NE WINDS OF 20-30KT TONIGHT...WITH
SOME GALE FORCE GUSTS TO AROUND 35 KT THRU THE EVENING. E TO NE
WINDS...MOSTLY 10-20KT...WILL THEN CONTINUE ON WED AND ON INTO THU
AS LOW PRES LIFTS NE FROM THE CENTRAL PLAINS INTO THE GREAT LAKES
REGION. AT THIS TIME...IT APPEARS THE LOW WILL NOT BE STRONG ENOUGH
TO RESULT IN GALES AS THE LOW APPROACHES AND THEN DEPARTS. WINDS
WILL BACK TO THE N THU AND THEN NW 20-30KT THU NIGHT INTO FRI AS THE
LOW SHIFTS TO THE E AND HIGH PRES BUILDS INTO THE PLAINS. A PERIOD
OF LIGHT WINDS WILL OCCUR FRI NIGHT INTO SAT AS HIGH PRES RIDGE
MOVES ACROSS THE UPPER LAKES. S WINDS WILL THEN BE ON THE INCREASE
TO AT LEAST 10-20KT ON SUN AS THE RIDGE SHIFTS E AND A LOW PRES TROF
MOVES E TO THE UPPER MISSISSIPPI VALLEY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DULUTH MN
326 AM CDT WED APR 8 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 325 AM CDT WED APR 8 2015
LAST OF THE PIECES OF SHORT WAVE ENERGY EARLY THIS MORNING WAS
MOVING ALONG THE INTERNATIONAL BORDER WHILE ANOTHER WAS EXITING NW
WI JUST BEFORE 08Z. THE LIGHT FREEZING RAIN IS COMING TO AN
END...BUT SOME LIGHT SNOW REMAINS ALONG THE INTERNATIONAL BORDER
AREA. CALLS TO AREA LAW ENFORCEMENT REVEALED NO SLIPPERY ROADS DUE
TO THE FREEZING RAIN. THE LIGHT ICE ACCUMULATION WAS ALL ELEVATED. 2
INCHES OF SNOW WAS REPORTED AT INL WITH THE 06Z OB. LITTLE IN THE
WAY OF ADDITIONAL ACCUMULATION IS EXPECTED BEFORE 12Z.
MODELS ARE INDICATING ONE LAST PIECE OF ENERGY WILL CROSS NORTHERN
MN THIS MORNING AND HAVE POPS AROUND THE PERIPHERY OF LAKE SUPERIOR
TO REFLECT THIS TREND. THERE IS STILL A POTENTIAL FOR SOME LIGHT
FREEZING RAIN...SNOW OR SLEET...ESPECIALLY OVER THE TIP OF THE
ARROWHEAD. HAVE A LIGHT ICE ACCUMULATION MENTIONED. ELSEWHERE...THE
HIGH PRESSURE REMAINS IN CHARGE. THE PRECIPITATION WILL END BY 15Z.
MODELS ARE IN GENERAL AGREEMENT WEDNESDAY EVENING WITH SFC RIDGING
COVERING A MAJORITY OF THE FORECAST AREA. THE EXCEPTION IS THE NAM
WHICH IS TRYING TO GENERATE SOME PCPN UP THE NORTH SHORE. GFS IS TOO
FAST AND TOO FAR NORTH WITH ITS QPF PRIOR TO 06Z. AS A
COMPROMISE...HAVE SOME SMALL POPS TO ACCOUNT FOR THESE TRENDS. AFTER
06Z...MODEL DIFFERENCES BECOME A BIT LARGER WITH RESPECT TO NEXT
ROUND OF PCPN SPREADING NORTHWARD FROM SOUTHERN MINNESOTA AND HIGH
PRESSURE OVER THE FORECAST AREA. TRIED TO ALIGN POPS/QPF/WEATHER TO
BETTER REFLECT MODEL SOLUTIONS AND MATCH NEIGHBORING OFFICES. THERE
WILL BE MORE MIXED PCPN AS WAA MOVES OVER THE TOP OF COLD AIR IN THE
LOWEST LEVELS.
ON THURSDAY...A SFC LOW WILL MOVE FROM SW IA TO SE WI.
MEANWHILE...AN UPPER LEVEL TROF WITH SEVERAL PIECES OF SHORT WAVE
ENERGY WILL AFFECT THE FORECAST AREA. AT THIS TIME...IT APPEARS THAT
NO PCPN WILL OCCUR TO THE WEST OF A LINE FROM LONGVILLE TO HIBBING
TO NEAR ELY. HAVE REMOVED POPS AS A RESULT. EXPECT A RAIN/SNOW/SLEET
MIX IN THE MORNING BEFORE TRANSITIONING TO ALL SNOW IN THE
AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 325 AM CDT WED APR 8 2015
COLD UPPER TROUGH WILL BE SLOWLY EXITING TO THE ESE THURSDAY NIGHT
AND FRIDAY MORNING WITH A WINTRY MIX OF RAIN...SNOW...SLEET AND
POSSIBLY FREEZING RAIN ASSOCIATED WITH IT THURSDAY EVENING AND A
CHANGE OVER TO ALL SNOW LATE THURSDAY NIGHT. COULD SEE A COUPLE
INCHES OF SNOW/SLEET OVER PORTIONS OF NW WI DURING THIS TIME...WITH
LIGHT ICING AS WELL. TRAVEL CONDITIONS COULD DETERIORATE RAPIDLY. AS
THE MAIN FORCING FROM THIS SYSTEM MOVES EWD...THE COLD AIR BEHIND
THE FRONT WILL POUR IN FROM THE NW AND TRIGGER ADDITIONAL CHANCES
FOR WEAK CONVECTIVE SNOW SHOWERS FRIDAY MORNING AND RAIN SHOWERS IN
THE AFTERNOON. ADDITIONAL PRECIP AMTS WILL BE LIGHT. A LARGE WARM
RIDGE OF HIGH PRESSURE WILL BUILD IN THIS WEEKEND AND KEEP
CONDITIONS QUIET THROUGH SUN MORNING. THE NEXT TROUGH MOVES IN
SUNDAY AFTERNOON WITH LIGHT RAIN CHANCES INTO EARLY MONDAY. HIGH
PRESSURE SETTLES IN OVER NORTHERN MINNESOTA BY TUESDAY.
TEMPERATURES WILL WARM QUICKLY THROUGH THE END OF THE WEEK WITH
HIGHS ON FRIDAY IN THE UPPER 30S TO LOWER 50S...AND INTO THE 50S AND
LOWER 60S BY SUNDAY. OVERNIGHT LOWS IN THE 20S AND LOWER 30S ARE
EXPECTED FRI AND SAT MORNING...WITH 30S AND 40S LATER IN THE WEEKEND
AND EARLY NEXT WEEK. CONDITIONS WILL REMAIN MILD INTO THE EARLY TO
MIDDLE PART OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1220 AM CDT WED APR 8 2015
PRECIPITATION RANGED FROM LIGHT RAIN OVER PORTIONS OF NORTHERN
WISCONSIN...TO SNOW ALONG THE INTERNATIONAL BORDER. BETWEEN THESE
TWO AREAS WAS SLEET...SNOW AND FREEZING RAIN. IFR CONDITIONS WILL
OCCUR IN THE HEAVIER SNOW OVER FAR NORTHERN MINNESOTA...WITH MAINLY
MVFR CONDITIONS ELSEWHERE. THE PRECIPITATION WILL DIMINISH FROM THE
WEST AND SOUTH LATER TONIGHT.
A PERIOD OF FREEZING DRIZZLE/DRIZZLE AND FOG WILL BE POSSIBLE AS THE
PRECIP EXITS THE AREA AND A MIX OF LOW MVFR/IFR CONDITIONS WILL
PREVAIL INTO WEDNESDAY MORNING. THE LATEST NAM SUGGEST CEILINGS WILL
RISE THROUGH THE DAY AND BECOME SCATTERED IN SPOTS. HOWEVER...THE
LATEST RAP KEEPS THE CLOUDS AROUND LONGER. WE SIDED WITH THE RAP.
SOME OF THE GUIDANCE SHOWS SOME FOG AND LOWER CEILINGS MOVING BACK
IN WEDNESDAY EVENING...AND WE TRENDED THAT WAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 39 31 41 31 / 10 50 60 30
INL 45 29 49 28 / 0 30 0 30
BRD 48 35 48 27 / 0 60 40 20
HYR 48 35 42 30 / 10 60 80 60
ASX 41 32 38 30 / 20 50 80 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
141>148.
&&
$$
SHORT TERM...GSF
LONG TERM...BJT
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1222 AM CDT WED APR 8 2015
.UPDATE...
ISSUED AT 1220 AM CDT WED APR 8 2015
UPDATED FOR AVIATION DISCUSSION BELOW.
UPDATE ISSUED AT 936 PM CDT TUE APR 7 2015
HAVE UPDATED GRIDS THIS EVENING TO ACCOUNT FOR LATEST TRENDS
REGARDING COVERAGE AND PRECIP TYPE. SPOTTER AND LAW ENFORCEMENT
REPORT FREEZING RAIN OVER PORTIONS OF AITKIN AND FAR SOUTHERN
ITASCA COUNTIES WITH SLEET AND SNOW FURTHER NORTH. WE THOUGHT
ABOUT ISSUING AN ADVISORY FOR SEVERAL HOURS IN THE AREA GETTING
THE FREEZING RAIN...BUT DECIDED TO HOLD OFF FOR NOW BASED ON
CURRENT RADAR TRENDS. WE WILL WATCH CLOSELY.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 335 PM CDT TUE APR 7 2015
CLOUDY TODAY WITH BREEZY CONDITIONS ALONG THE HEAD OF LAKE SUPERIOR
DUE TO NORTHEASTERLY WINDS ACROSS THE LAKE. TONIGHT A COMPLEX WINTRY
MIX WILL DEVELOP ACROSS MUCH OF THE REGION WHICH WILL BRING A MIX OF
SNOW...SLEET...AND FREEZING RAIN AND POSSIBLY RESULT IN A MESSY
WEDNESDAY MORNING COMMUTE FOR THE NORTHLAND. A MID-LEVEL DRY SLOT
WILL BE QUICK TO MOVE IN BEHIND THIS SYSTEM BY WEDNESDAY MORNING BUT
LOW LEVEL CLOUDS WILL STICK AROUND FOR MOST OF THE DAY.
ON THE SYNOPTIC SCALE THE PRIMARY FEATURE AFFECTING OUR WEATHER IN
THE SHORT TERM IS A MID-LEVEL SHORTWAVE TROUGH MOVING ACROSS
SOUTHERN SASASK/MANITOBA. ACROSS THE CONUS A DEEPENING TROUGH OFF
THE CALIFORNIA COAST AND A NEAR-ZONAL FLOW ACROSS THE EASTERN
SEABOARD IS RESULTING IN SOUTHWESTERLY FLOW FROM THE
CENTRAL/SOUTHERN ROCKIES AND DESERT SOUTHWEST EAST TO THE UPPER
GREAT LAKES AND MISSISSIPPI RIVER VALLEY. AT THE SURFACE AN AREA OF
HIGH PRESSURE OVER MUCH OF ONTARIO AND A SFC LOW IN EASTERN KANSAS
IS RESULTING IN EASTERLY FLOW AT THE SFC.
REST OF TODAY...GENERALLY CLOUDY AND SLIGHTLY COOLER THAN NORMAL. IN
THE TWIN PORTS AND NEARBY COASTAL AREAS WINDS ARE BREEZY /GUSTING TO
NEAR 30 KTS/ DUE TO NORTHEASTERLY WINDS ACROSS LAKE SUPERIOR...WHICH
IS ALSO CAUSING TEMPS TO BE COOLER THAN SURROUNDING AREAS. ELSEWHERE
LIGHT EASTERLY WINDS WITH TEMPS IN THE MID 30S TO NEAR 40...WARMEST
ALONG THE INTERNATIONAL BORDER WHERE CLOUDS WERE MORE SCATTERED
ALLOWING SUNSHINE THROUGH. CONDITIONS ARE GENERALLY VERY DRY...AND
IN AREAS WHERE SUNSHINE HAS BEEN ABLE TO BREAK THROUGH THE CLOUDS
IT IS UNUSUALLY DRY...WITH RELATIVE HUMIDITY 20 TO 30 PERCENT. THIS
DRY AIRMASS WILL DELAY THE INITIAL ONSET ON PRECIP...AND WHILE SOME
SPORADIC LIGHT RAIN/SLEET HAS BEEN REPORTED ACROSS CASS/CROW
WING/AITKIN COUNTIES THIS AFTERNOON...IT HAS BEEN DRY FOR THE MOST
PART DUE TO T/TD SPREADS OF 15 TO 30 DEGREES ACROSS MUCH OF
NORTHEAST MINNESOTA.
TONIGHT...A WINTRY MIX WILL SPREAD OVER THE REGION TONIGHT
ASSOCIATED WITH A QUICK-MOVING MID-LEVEL TROUGH AXIS MOVING
NORTHEAST ACROSS THE REGION TONIGHT. SOUTHERLY WINDS AT LOW/MID
LEVELS /EG. 925MB TO 700MB/ WILL RESULT IN WARM AIR ADVECTION
THROUGHOUT THE NIGHT...BRINGING A WARM LAYER ALOFT INTO NORTHWEST
WISCONSIN AND MUCH OF NORTHEASTERN MINNESOTA ALONG/SOUTH OF HIGHWAY
2. THIS COMBINATION OF TROUGH MOVING ACROSS THE REGION AND WARM AIR
ADVECTION WILL PROVIDE AMPLE LARGE-SCALE FORCING FOR PRECIPITATION
ACROSS THE REGION.
AS FAR AS PRECIPITATION TYPE GOES...SHORT RANGE GUIDANCE HAS BEEN
TRENDING TOWARDS WEAKER WARM AIR ADVECTION...MEANING PRECIP WOULD BE
MORE SNOW THAN FREEZING RAIN/SLEET. THE EXCEPTION WILL BE ACROSS FAR
SOUTHERN PORTION OF THE CWA WHERE PRECIP WILL BE MORE RAIN/SLEET
THAN SNOW...BUT GIVEN MODEL TRENDS WOULD NOT BE SURPRISED IF THESE
LOCATIONS TOO WERE MAINLY SNOW. AS FAR AS SNOWFALL TOTALS GO...ONE
TO THREE INCHES IN NORTHEAST MINNESOTA /NORTH OF HWY 2/...WITH LESS
THAN AN INCH ALONG HWY 2 AND LITTLE TO NO ACCUMULATION TO THE SOUTH
DUE TO RAIN MIXING IN AT TIMES.
DECIDED NOT TO ISSUE A WINTER WEATHER ADVISORY AT THIS TIME MAINLY
BECAUSE OF THE LIGHT PRECIP AMOUNTS. WHERE PRECIP WILL BE MAINLY
SNOW /MOST OF NORTHEAST MINNESOTA/ SNOWFALL AMOUNTS WILL BE
GENERALLY LESS THAN THREE INCHES...AND WHERE A MIX IS EXPECTED IT IS
NOT EXPECTED TO LAST VERY LONG. IN NORTHWEST WISCONSIN SFC TEMPS
WILL BE NEAR TO JUST ABOVE FREEZING...LIMITING ICE/SNOW ACCUMULATION
ON ROADWAYS. HAVE DECIDED INSTEAD TO ISSUE AN SPS TO GIVE A HEADS UP
FOR A SLICK COMMUTE.
WEDNESDAY...MID-LEVEL DRYING BEHIND THE TROUGH WILL LEAD TO A QUICK
END OF PRECIP...POSSIBLY AS DRIZZLE/FREEZING DRIZZLE...BUT LOW
CLOUDS WILL STICK AROUND THROUGHOUT MOST OF THE DAY. A WEAK
MID-LEVEL RIDGE MOVING ACROSS THE MIDWEST MAY LEAD TO SOME PARTIAL
CLEARING...BUT GENERALLY EXPECT CLOUDY SKIES. LIGHT EASTERLY WINDS
WITH NORTHEAST WINDS OVER THE LAKE...BUT MUCH LESS WINDY THAN TODAY.
HIGHS IN THE LOW TO MID 40S INLAND...AND MID TO UPPER 30S NEAR LAKE
SUPERIOR.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 335 PM CDT TUE APR 7 2015
THE MESSY SPRING PATTERN WILL CONTINUE THROUGHOUT THE WORK WEEK...AS
THE MAIN SHORTWAVE IN THE SOUTHWEST FLOW PATTERN EJECTS INTO THE
PLAINS AND THEN UPPER MIDWEST FROM WEDNESDAY NIGHT INTO THURSDAY
NIGHT. THE FIRST BATCH OF WAA INDUCED PRECIPITATION WILL ARRIVE
WEDNESDAY NIGHT...FOLLOWED BY PRECIPITATION FROM THE UPPER LEVEL
SYSTEM INTO THURSDAY AND THURSDAY NIGHT. AS HAS BEEN THE CASE THIS
WEEK...WE WILL LIKELY SEE MYRIAD OF WINTER WEATHER CONDITIONS DURING
THE DIFFERENT PHASES OF THE EVOLUTION OF THIS MORE MAJOR SYSTEM.
STILL NOT RULING OUT THE POTENTIAL FOR SOME SNOW ACCUMULATION WITH
THE SYSTEM...ESPECIALLY ACROSS THE NORTH AND ESPECIALLY IN THE AREA
OF DEFORMATION ON THE BACK SIDE OF THE DEPARTING SYSTEM. IT DOES
LOOK LIKE THERE WILL BE A MIX OF RAIN...FREEZING RAIN...SLEET AND
SNOW WITH MOST PLACES SEEING A FAIRLY WIDESPREAD PERIOD OF
PRECIPITATION FROM WEDNESDAY NIGHT INTO THURSDAY NIGHT. SOME
SCATTERED SNOW SHOWERS WILL THEN LINGER INTO FRIDAY MORNING AS THE
COLD CORE MOVES ACROSS THE CWA. SHOULD BE MAINLY RAIN SHOWERS BY
AFTERNOON FRIDAY. SATURDAY IS SHAPING UP TO BE A GENERALLY DRY
DAY...WITH ANOTHER CHANCE OF RAIN SHOWERS MOVING BACK IN ON SUNDAY
AND SUNDAY NIGHT. LOOKS LIKE DEEP MOISTURE WITH THIS SYSTEM AND
WOULD NOT BE SURPRISED TO SEE A FEW THUNDERSTORMS AS WELL. HIGH
TEMPERATURES WILL WARM INTO THE WEEKEND...WITH 50S AND 60S BY THE
WEEKEND AND INTO EARLY IN THE WORK WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1220 AM CDT WED APR 8 2015
PRECIPITATION RANGED FROM LIGHT RAIN OVER PORTIONS OF NORTHERN
WISCONSIN...TO SNOW ALONG THE INTERNATIONAL BORDER. BETWEEN THESE
TWO AREAS WAS SLEET...SNOW AND FREEZING RAIN. IFR CONDITIONS WILL
OCCUR IN THE HEAVIER SNOW OVER FAR NORTHERN MINNESOTA...WITH MAINLY
MVFR CONDITIONS ELSEWHERE. THE PRECIPITATION WILL DIMINISH FROM THE
WEST AND SOUTH LATER TONIGHT.
A PERIOD OF FREEZING DRIZZLE/DRIZZLE AND FOG WILL BE POSSIBLE AS THE
PRECIP EXITS THE AREA AND A MIX OF LOW MVFR/IFR CONDITIONS WILL
PREVAIL INTO WEDNESDAY MORNING. THE LATEST NAM SUGGEST CEILINGS WILL
RISE THROUGH THE DAY AND BECOME SCATTERED IN SPOTS. HOWEVER...THE
LATEST RAP KEEPS THE CLOUDS AROUND LONGER. WE SIDED WITH THE RAP.
SOME OF THE GUIDANCE SHOWS SOME FOG AND LOWER CEILINGS MOVING BACK
IN WEDNESDAY EVENING...AND WE TRENDED THAT WAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 32 41 30 51 / 80 70 50 20
INL 31 49 27 49 / 60 40 20 20
BRD 31 47 29 53 / 80 60 40 20
HYR 33 45 30 50 / 80 80 70 30
ASX 32 41 30 45 / 80 70 60 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
141>148.
&&
$$
SHORT TERM...JJM
LONG TERM...DAP
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1110 PM CDT TUE APR 7 2015
.UPDATE...
ISSUED AT 1104 PM CDT TUE APR 7 2015
UPDATED TO INCLUDE 06Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 330 PM CDT TUE APR 7 2015
CURRENT CONDITIONS SYNOPSIS...
CLUSTER OF SHOWERS AND EMBEDDED THUNDERSTORMS CURRENTLY MOVING
THROUGH THE SOUTHERN PORTION OF THE AREA ALONG THE NORTHERN
PERIPHERY OF THE INSTABILITY... WITH A NOTABLE GRADIENT IN MUCAPE
JUMPING FROM 0 TO 500 J/KG SOUTH OF THE BORDER. DEEP LAYER SHEAR
IS STRONG... AND ONE STORM DID BRIEFLY SHOW SOME MID-LEVEL
ROTATION... AND MANAGED TO PRODUCE MARGINALLY SEVERE HAIL. THE
ACTIVITY SHOULD TRANSLATE EAST AND FOCUS MORE SOUTH AS THE
SHORTWAVE EVIDENT ON WATER VAPOR NEAR THE NEBRASKA/IOWA BORDERS
SHIFTS EAST THROUGH EARLY EVENING.
FORECAST ITEM/S/ OF CONCERN...
CHANCES FOR PCPN... SOME THUNDER... AND PERHAPS SOME MIXED PCPN
INTO TONIGHT... WITH THINGS DRYING OUT WEDNESDAY.
MODEL DISCUSSION/PREFERENCES...
PRIMARILY RELYING ON CAM GUIDANCE... PARTICULARLY HRRR AND HOPWRF
MEMBERS... WHICH HAVE A DECENT HANDLE ON CURRENT CONVECTIVE
ACTIVITY ACROSS THE AREA... BLENDING MORE TOWARD NAM/GFS SOLUTIONS
ON WEDNESDAY.
SENSIBLE WEATHER EXPECTATIONS...
EXPECT SHRA AND EMBEDDED TSRA TO IMPACT THE SOUTHERN PORTION OF
THE AREA INTO PERHAPS THE EARLY EVENING... OTHERWISE WILL SEE
PCPN ON THE NORTH SIDE OF SURFACE LOW MOVE EAST ACROSS THE AREA
THROUGH THE REMAINDER OF THE EVENING. SOME SLEET COULD MIX IN AT
TIMES OVER THE NORTH AND NORTHEAST PORTION OF THE AREA WHERE THE
WARM LAYER IS A BIT LESS DEEP. SHOULD SEE ENOUGH DRYING/SUBSIDENCE
IN THE MID-LEVELS FOR PCPN TO COME TO AN END LATER TONIGHT... WITH
DRY WEATHER OTHER THAN PERHAPS SOME PATCHY DRIZZLE THROUGH MOST OF
WEDNESDAY. SOME SHRA COULD WORK BACK INTO THE SOUTHERN PART OF THE
AREA BY LATER WEDNESDAY AS THE NEXT SHORTWAVE AND SURFACE IMPULSE
ALONG THE BAROCLINIC ZONE WORK INTO THE REGION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 PM CDT TUE APR 7 2015
THE STORM SYSTEM OFF THE COAST OF CALIFORNIA WILL IMPACT OUR
REGION FROM WEDNESDAY NIGHT THRU EARLY FRIDAY MORNING. THE FIRST
PART OF THE STORM HAS THE POTENTIAL OF SVR WX IN THE FAR SE BASED
ON STABILITY PARAMETERS...LOW FREEZING LEVEL AND MID LEVEL LAPSE
RATES. THE BEST POTENTIAL WILL BE THURSDAY AFTERNOON FROM ALBERT
LEA...NORTHEAST TO EAU CLAIRE WISCONSIN. SEE THE LATEST SPC DAY 3
OUTLOOK.
SEVERAL FACTORS NEED TO COME TOGETHER FOR SNOWFALL TO ACCUMULATE
IN OUR CWA. FIRST...THE BEST CHC OF PRECIPITATION AND HIGHER
PRECIPITATION RATES OCCUR BETWEEN 18Z THU TO 06Z FRIDAY. THE SFC
LOW REMAINS IN A FAVORABLE TRACK FOR THE PRECIPITATION TO CHANGE
OVER TO SNOW DURING THE LATE AFTN/EVENING. HOWEVER...THERMAL
PROFILERS REMAINED UNFAVORABLE OF THIS CHANGE OVER IN OUR
CWA...WITH ONLY A SMALL AREA OF THICKNESS VALUES DROPPING TO
CRITICAL LEVELS IN EC MN/WC WI THURSDAY EVENING. THERE REMAINS A
VERY STRONG SIGNAL OF A TROWAL AND DEFORMATION ZONE DEVELOPMENT IN
EC MN/WC WI THURSDAY EVENING. AS WITH PREVIOUS DISCUSSIONS...
THERE IS A POTENTIAL OF HEAVY SNOWFALL IN A SMALL BAND IF ALL THE
WEATHER ELEMENTS COME TOGETHER. IN ADDITION...A CROSS SECTION OF
THE ATMOSPHERE FROM WC MN TO SOUTHERN WI HAS EC MN IN FAVORABLE
AREA OF CONVECTIVE STABILITY INDEX /CSI/ AND SLANTWISE CONVECTIVE.
THEREFORE...IT IS HIGHLY PROBABLE FOR SOMEWHERE IN EASTERN
MN/WESTERN WI TO SEE A HEAVY SNOWFALL EVENT THURSDAY EVENING IF
THIS TYPE OF SCENARIO DEVELOPS.
PAST THURSDAY...A COOL PERIOD WILL OCCUR FROM FRIDAY THRU
SATURDAY BEFORE SOUTHERLY FLOW BEGINS. LATE IN THE WEEKEND AND
INTO NEXT WEEK REMAIN VERY UNSETTLED AS ANOTHER STORM SYSTEM
BEGINS TO DEVELOP ACROSS THE CENTRAL U.S. WITH THIS TYPE OF
PATTERN...TEMPS MAY FLUCTUATE RAPIDLY BASED ON THE AMOUNT CLOUD
COVER AND PRECIPITATION POTENTIAL...BUT AN OVERALL MEAN IS TO
CONTINUE WITH SLIGHTLY BLW NORMAL TEMPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1104 PM CDT TUE APR 7 2015
ISOLATED CLUSTERS OF -RA/-IP HAVE DEVELOPED OVER NORTHERN PORTIONS
OF THE COVERAGE AREA...MAINLY AFFECTING KAXN-KSTC...WITH POSSIBLY
SOME -SHRA AS FAR S AS KMSP-KRNH-KEAU. PRECIP IS VERY LIGHT...IF
ANYTHING IS AT ALL RECEIVED...AND IS NOT EXPECTED TO PRODUCE
REDUCTIONS IN VSBY. HOWEVER...WHAT WILL CAUSE REDUCTIONS IN
FLIGHT CATEGORY IS LOW CEILINGS. CEILINGS ARE WIDESPREAD SOLIDLY
IN MVFR AT INITIALIZATION TIME AND WILL CONTINUE TO DROP THROUGH
LOWER-RANGE MVFR TO IFR BY SUNRISE AND LAST THERE THRU LATE
MORNING BEFORE RECOVERING MIDDAY. CEILINGS WILL LIKELY REMAIN IN
MVFR ALL DAY WEDNESDAY...IN ADVANCE OF ADDITIONAL RAINFALL
THURSDAY EVENING ACROSS ALL TAF SITES. WINDS WILL REMAIN GENERALLY
OUT OF THE E TO NE WITH SPEEDS IN THE 5-10 KT RANGE.
KMSP...NOT LOOKING FOR PRECIP TO REACH KMSP OVERNIGHT BUT A FEW
SPRINKLES/SHOWERS CANNOT BE RULED OUT. THE MAIN ISSUE WILL BE
CEILINGS THAT DROP INTO MVFR AND IFR THROUGH THE MORNING PUSH.
MVFR CEILINGS THEN REMAIN IN PLACE THRU THE WED EVENING PUSH BUT
ADDITIONAL PRECIP LOOKS TO HOLD OFF UNTIL LATE EVE.
/OUTLOOK FOR KMSP/
THU...MVFR POSSIBLY IFR. RA LIKELY. WINDS N 15-25 KTS.
FRI...VFR. WINDS NW 10-15 KTS.
SAT...VFR. WINDS S 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...JPC
SHORT TERM...
LONG TERM...JLT
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
342 AM CDT WED APR 8 2015
.SYNOPSIS...
ISSUED AT 342 AM CDT WED APR 8 2015
H5 ANALYSIS FROM EARLIER THIS EVENING HAD A CLOSED LOW OVER NRN
CALIFORNIA WITH A TROUGH OF LOW PRESSURE EXTENDING SWD INTO SO
CALIFORNIA. SWLY FLOW ALOFT EXTENDED FROM THE SWRN CONUS NEWD INTO
THE ROCKIES AND PLAINS STATES. WV IMAGERY TONIGHT HAS THE BULK OF
MID AND UPPER LEVEL MOISTURE WITH THIS FEATURE ACROSS MEXICO AND
TEXAS. FURTHER NORTH...MAINLY DRY MID AND UPPER LEVELS WERE
NOTED...HOWEVER A SMALL DISTURBANCE...HAS SPREAD MID LEVEL CLOUDS
AND SHOWERS TO THE NORTHWESTERN CWA TONIGHT...WITH AN OCCASIONAL
LIGHTNING STRIKE NOTED. FOR THE REMAINDER OF THE FORECAST AREA...A
MOIST BOUNDARY LAYER AND EASTERLY WINDS...HAS LED TO ANOTHER NIGHT
OF LOW CLOUDS...FOG AND DRIZZLE. AT THE SURFACE...A STATIONARY
FRONT EXTENDED FROM AROUND COLORADO SPRINGS...SEWD TO THE KS/OK
BORDER. NORTH OF THE FRONT...EASTERLY WINDS AND MOSTLY CLOUDY
SKIES WERE PRESENT ACROSS ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA. AS OF 3 AM CDT...TEMPERATURES RANGED FROM 39 AT
VALENTINE AND AINSWORTH TO 43 AT IMPERIAL AND OGALLALA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CDT WED APR 8 2015
THE MAIN FORECAST CHALLENGE OVER THE NEXT TWO PERIODS IS
PRECIPITATION CHANCES AND PRECIPITATION TYPES OVERNIGHT TONIGHT.
FOR TODAY...EASTERLY WINDS WILL CONTINUE TO FAVOR LOW CLOUDS FOR
MOST OF THE FORECAST AREA. SOME CLEARING IS POSSIBLE IN THE
PANHANDLE ZONES AND ACROSS FAR SWRN PORTIONS OF THE CWA THIS
AFTERNOON...PER HRRR AND NAM12 H85 AND H85-H90 RH FIELDS. WITH
THIS IN MIND...FILTERED SUN WILL LEAD TO HIGHS IN THE UPPER 50S.
ELSEWHERE...HIGHS WILL RANGE FROM THE UPPER 40S TO LOWER 50S. LATE
THIS AFTERNOON AS THE UPPER LEVEL LOW PUSHES EAST INTO WESTERN
WYOMING...NRN UT AND NWRN COLORADO ELEVATED AND SURFACE BASED
INSTABILITY WILL BEGIN TO INCREASE ACROSS THE PANHANDLE. THE
LATEST NAM12 IS INDICATIVE OF NEGATIVE LI`S ACROSS THE PANHANDLE
FROM 21Z THROUGH 03Z AND ACROSS PORTIONS OF SWRN NEBRASKA WITH
ELEVATED INSTABILITY FROM 00Z THROUGH 06Z THIS EVENING. DID GO
AHEAD AND INTRODUCE THUNDERSTORMS TO THE FORECAST IN THE FAR WEST
AND SWRN CWA FOR LATE THIS AFTERNOON AND EVENING IN LIGHT OF THE
NEGATIVE LI/S. AS FOR PCPN CHANCES...THE HIGHEST POPS WILL
CONTINUE IN THE WEST AND NORTHWEST...TRANSITIONING ACROSS THE
SANDHILLS AND NORTH CENTRAL NEBRASKA OVERNIGHT. THESE AREAS ARE IN
THE MOST FAVORABLE AREAS FOR ISENTROPIC LIFT AHEAD OF THE APPG
TROUGH THIS EVENING...THEN IN THE WRAP AROUND OVERNIGHT. AS FOR
PRECIPITATION TYPE OVERNIGHT...DECIDED TO KEEP THE BULK OF PCPN AS
ALL RAIN AS BUFKIT SOUNDINGS INDICATE ONLY A 1 TO 2 HOUR WINDOW
FOR CHANGEOVER TO SNOW...AND THIS IS MAINLY THURSDAY MORNING
ACROSS THE FAR NORTHWESTERN AND NORTHERN CWA. DECIDED TO WORD THE
FCST AS RAIN OR SNOW...AS LOWS ARE ONLY EXPECTED TO DROP INTO 33
TO 35 DEGREE RANGE IN THE NORTHWEST OVERNIGHT. AS FOR SNOW
ACCUMS...DECIDED TO KEEP THESE AT A MINIMUM AS IT IS EXPECTED TO
MIX WITH RAIN...AND WARM GROUND CONDS SHOULD LIMIT ANY ACCUMS IF
THEY DO OCCUR.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 342 AM CDT WED APR 8 2015
UPPER LEVEL TROUGH AND ASSOCIATED COLD POOL WILL WORK EAST ACROSS
THE FORECAST AREA ON THURSDAY. PRECIPITATION IS EXPECTED TO
CONTINUE THROUGH MUCH OF THE MORNING HOURS...BUT BEGIN TO WANE IN
THE AFTERNOON AS SYSTEM RELATIVE UPGLIDE ASSOCIATED WITH A FRONTAL
BOUNDARY SHIFTS SOUTH AND EAST. IN ADDITION...LARGE SCALE LIFT
DECREASES AS THE TROUGH AXIS WORKS INTO EASTERN IOWA BY MID
AFTERNOON. PRECIPITATION AMOUNTS ARE ANTICIPATED TO BE LIGHT
DURING THE DAYLIGHT HOURS. MOST LOCATIONS WILL ONLY ACCUMULATE A
FEW ADDITIONAL TENTHS AT MOST. WHAT CONTINUES TO BE THE GREATEST
ENIGMA WITH THIS SYSTEM IS WHEN AND IF A CHANGE OVER TO SNOW WERE
TO OCCUR. ENOUGH MID AND UPPER LEVEL COOLING WILL HELP WITH THE
CHANGE OVER...ESPECIALLY SINCE H85-H9 TEMPERATURES FALL BELOW 0C
AFTER 12Z ACROSS OUR NORTHWEST THURSDAY MORNING. WOULD EXPECT THAT
THE FROZEN HYDROMETEOR WOULD MAKE IT TO THE SURFACE...BUT SFC T/S
ARE SHOWN LARGELY TO REMAIN JUST ABOVE 0C. CURRENT THINKING IS
THAT A CHANGE OVER WILL OCCUR...AFTER SUNRISE THURSDAY...BUT THEN
QUICKLY CHANGE BACK TO ALL RAIN AS THE DIURNAL HEATING TAKES
CONTROL. WHERE THERE IS ENHANCEMENT OF QPF FALLING AS SNOW...SOME
ACCUMULATION MAY OCCUR FOR AN HOUR OR TWO PERIOD. HOWEVER WITH THE
RECENT WARM SPELL GROUND TEMPERATURES WOULD SUPPORT MELTING...THUS
ACCUMULATIONS WOULD BE INSIGNIFICANT...A COUPLE TENTHS AT MOST.
NORTHWEST FLOW WILL TRANSPORT COOLER AIR INTO THE REGION
OVERNIGHT...WITH MORNING LOWS BELOW 0C FOR THE ENTIRE CWA FRIDAY
MORNING.
RETURN FLOW AND TRANSITORY UPPER RIDGING WILL PROMOTE A QUICK
WARM-UP ON FRIDAY. HIGHS WILL CLIMB BACK INTO THE 60S. THE RETURN
FLOW WILL ALLOW FOR AN INCREASE IN MOISTURE ACROSS THE HIGH PLAINS
AND WEST CENTRAL NEBRASKA. A THETA-E GRADIENT NOSES INTO THE
FORECAST AREA EARLY SATURDAY. ELEVATED INSTABILITY DEVELOPS ALONG
THE GRADIENT...WITH LI/S APPROACHING -5C BY SATURDAY AFTERNOON. A
FEW ELEVATED STORMS ARE POSSIBLE.
SUNDAY...A SIMILAR SETUP IS IN PLACE HOWEVER THE MODELS SHOW A COLD
FRONT ADVANCING ACROSS THE CWA EARLY AFTERNOON. MODEL CONSISTENCY
IS NOT TOO STRONG AT THIS POINT...BUT SUFFICIENT ENOUGH FOR A
MENTION OF THUNDERS ONCE AGAIN ESPECIALLY ALONG AND SOUTH OF THE
FRONT. WILL NEED TO WATCH AS PRE-FRONTAL CONDITIONS WOULD HAVE
SLIGHTLY MORE ENERGY TO WORK WITH.
THE PATTERN REMAINS ACTIVE EARLY NEXT WEEK...AND WILL HAVE TO WATCH
THE PROGRESSION OF A SOUTHERN STREAM CLOSED LOW...WHICH MAY BRING
ADDITIONAL CHANCES OF QPF TO THE REGION. THE INIT GAVE US SLIGHT
CHANCES...WHICH IS REASONABLE GIVEN A LACK OF CONSISTENCY IN THE
LONG RANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1135 PM CDT TUE APR 7 2015
LIFR CEILINGS CONTINUE FROM KVTN AND KBBW AND AREAS TO THE EAST.
IFR CEILINGS AT KLBF ARE FORECAST TO BECOME LIFR AT 3SM -DZ BR
OVC004 FROM 08Z-16Z...THEN P6SM OVC007 TIL 18Z. AFTER 18Z MVFR
CEILINGS ARE EXPECTED. AT KVTN...LIFR CEILINGS NEAR 2SM -DZ BR
OVC002 UNTIL 18Z...THEN MVFR FOR REMAINDER OF PERIOD.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...JACOBS
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
204 AM EDT WED APR 8 2015
.SYNOPSIS...
A FRONTAL BOUNDARY STALLED FROM THE OHIO VALLEY TO THE MID
ATLANTIC COAST WILL PROVIDE PERIODS OF UNSETTLED WEATHER AROUND
THE REGION THROUGH THURSDAY. TEMPERATURES WILL GENERALLY SUPPORT
RAIN DURING THE DAYLIGHT HOURS...BUT MAY TAIL OFF TO BELOW
FREEZING AT NIGHT...PROVIDING A CHANCE FOR SOME LIGHT FREEZING
RAIN OR SLEET BOTH LATE TONIGHT AND AGAIN LATE WEDNESDAY NIGHT FOR
THE MOHAWK VALLEY...WESTERN CATSKILLS AND NORTHERN POCONOS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
950 PM UPDATE...
LATEST HRRR GUIDANCE FORECASTS THE NEXT SHORT WAVE / IMPULSE INVOF
OF ELEVATED WARM FRONT TO PUSH PRECIP INTO WESTERN FA AROUND 6Z.
THE PRECIPITATION WILL GRADUALLY SPREAD NORTH AND EAST THROUGHOUT
THE PREDAWN HOURS UNTIL RAIN SHOWERS COVER THE ENTIRE REGION FOR
THE MID-MORNING COMMUTE.
A VERY SLIGHT POSSIBILITY EXISTS FOR SLEET OR FREEZING RAIN OVER
THE NORTHERN FA, WHERE COLD AIR BLEEDS OFF OF THE HIGHER TERRAIN.
POPS ARE VERY LOW (MAINLY SLIGHT CHANCE TO LOW CHANCE) DURING THE
PERIOD OF THE MORNING WHEN TEMPS ARE MARGINAL, SO WILL KEEP THE
THREAT MINIMIZED. SEE NO NEED TO RAISE A FLAG FOR SUCH A LOW
PERCENTAGE EVENT.
4 PM UPDATE...
FAST ZONAL FLOW ALOFT WITH MINOR IMPULSES MOVING
ALONG AN 850-700 MB WARM FRONT OVER THE REGION WILL PROVIDE THE
NECESSARY FORCING FOR PERIODIC BOUTS OF PRECIPITATION THROUGH
THURSDAY. TIMING IS DIFFICULT IN THIS TYPE OF PATTERN TO GET A
HANDLE ON EXACTLY WHEN AND WHERE IT WILL HAPPEN...BUT 12Z MODELS
ARE SHOWING A LULL IN ACTION AS THIS FIRST WAVE DEPARTS THIS
EVENING...FOLLOWED BY A RESURGENCE OF ENERGY AFTER MIDNIGHT
AFFECTING MAINLY OUR SW ZONES...THEN THE NEPA AND WRN CATSKILLS
SHORTLY AFTER DAYBREAK. COLDER AND SLIGHTLY DRIER AIRMASS UNDER
HIGH PRESSURE OVER NRN NEW YORK WILL ALLOW FOR OUR NORTHERN AND
EASTERN ZONES TO DROP TO NEAR AND BELOW FREEZING BEFORE PRECIP
STARTS. EARLIER FORECASTS HAD MENTION OF FREEZING RAIN/SLEET FOR
THE MOHAWK VALLEY AND WRN CATS LATE TONIGHT AND EARLY WEDNESDAY
BEFORE WARMING. 12Z FORECAST SOUNDINGS AND GENERAL THICKNESS
FIELDS MAINTAIN THIS IDEA. NO WINTER HEADLINES AT THIS TIME AS THE
POPS ARE STILL UNCERTAIN AS TO THIS HAPPENING BEFORE TEMPS
WARM...AND TEMPS ARE RIGHT ON THE FREEZING LINE ANYWAY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
TIMING CONTINUES TO BE PROBLEMATIC IN THIS FAST PATTERN THROUGH
THURSDAY...HOWEVER THE 12Z GUIDANCE IS IN FAIR AGREEMENT ON A
COUPLE OF KEY PERIODS WHERE MOST OF OUR FORECAST AREA SHOULD SEE
PRECIP. A SURGE ALONG THE WARM FRONT ALOFT OCCURS WEDNESDAY
MORNING...FOLLOWED BY ANOTHER LULL WEDNESDAY NIGHT AND THURSDAY
MORNING. GREATER AMPLIFICATION OF THE PATTERN THEN TAKES PLACE
WITH A DEEPER BOUNDARY LAYER FLOW INCREASING ON THURSDAY AFTERNOON
WITH ADDITIONAL PERIODS OF RAIN SWEEPING INTO THE AREA.
WE CONTINUE TO SEE SIGNS OF CLASSIC COLD AIR DAMMING ALONG OUR
EASTERN ZONES AGAIN WEDNESDAY THROUGH THURSDAY WITH TEMPERATURES
STRUGGLING TO GET OUT OF THE UPPER 30S TOMORROW FROM THE CATSKILLS
TO THE NRN POCONOS. THIS WILL AGAIN SET THE STAGE FOR TEMPERATURES
TO SLIP BELOW FREEZING IN THESE AREAS AS SOME LINGERING
PRECIPITATION WORKS IN AGAIN LATER WEDNESDAY NIGHT AND EARLY
THURSDAY FOR ANOTHER POTENTIAL ROUND OF FREEZING RAIN OR SLEET.
WHEN ALL IS SAID AND DONE THURSDAY AFTERNOON...THERE COULD BE
QUITE A TEMPERATURE GRADIENT FROM THE FINGER LAKES TO THE POCONOS
RANGING FROM THE 50S TO THE UPPER 30S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
3 PM UPDATE...
THE UNSETTLED PATTERN WILL CONTINUE THROUGH THE FIRST PART OF THE
EXTENDED WITH FAIR WEATHER TO FOLLOW FOR THE WEEKEND.
EXPECT SHOWERS THURSDAY NIGHT ALONG AND AHEAD OF A WARM FRONT WITH
TEMPS NUDGING UP OVERNIGHT. WE ALSO CONTINUE TO MENTION THE SLIGHT
CHANCE OF ELEVATED CONVECTION OVER WESTERN ZONES. FOR FRIDAY,
STILL EXPECTING THE AREA TO BRIEFLY BREAK INTO THE WARM SECTOR
BEFORE A COLD FRONT MOVES THROUGH IN THE AFTERNOON. SHOWALTER
INDICES AND/OR LIFTED INDICES GET NEAR OR SLIGHTLY BELOW ZERO.
PRECIPITABLE WATER VALUES GET PAST 1.25 INCHES.. CAPE ITSELF WILL
BE VERY LIMITED...WHICH WILL HOLD BACK COVERAGE OF ANY
THUNDER...BUT THERE APPEARS TO BE GREAT JET SUPPORT VIA FORCED
ASCENT OF RIGHT ENTRANCE REGION. SO THERE WILL AT LEAST BE A GOOD
BATCH OF SHOWERS WITH THE FRONTAL PASSAGE. CONTINUED THE MENTION
OF THUNDER FOR MOST OF THE CWA BUT EXCLUDED NW AREAS OVER THE LAKE
PLAIN SINCE FRONT WILL CROSS THIS AREA EARLIER IN THE DAY.
ISOLATED LIGHT SHOWERS COULD STILL OCCUR IN THE BRIEF COLD AIR
ADVECTION BEHIND THE FRONT SATURDAY...MAINLY CENTRAL NY...BUT IN
GENERAL THINGS WILL DRY OUT THIS WEEKEND. HIGH PRESSURE SUNDAY
SHOULD YIELD SUNSHINE AND TEMPERATURES EDGING BACK ABOVE
CLIMATOLOGY AFTER A CHILLY DAWN. FURTHER WARMING EXPECTED EARLY
NEXT WEEK WITH THE NEXT CHANCE OF RAIN ARRIVING LATE MONDAY INTO
TUESDAY.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
WORST FLYING CONDITIONS THROUGH MID MORNING WILL BE THE SOUTHERN
TERMINALS. HERE WIDESPREAD MVFR CIGS AND VSBYS EXPECTED AS LIGHT
RAIN OVERSPREADS THE TERMINALS. AT KELM AND KITH SOME IFR CIGS ARE
POSSIBLE BETWEEN 09Z AND 14Z, WHILE AT KBGM IFR CIGS ARE LIKELY
FROM NOW THROUGH MID MORNING. IN FACT AT KBGM BELOW ALT MINS
LIKELY PRIOR TO DAYBREAK.
BY LATE MORNING CIGS SLOWLY CREEP UP INTO MVFR RANGE AS SHOWERS
COME TO AN END ACROSS THE SOUTH. UP NORTH SHOWERS BECOME MORE
LIKELY WITH MVFR CIGS AND VSBYS IN RESPONSE TO THE SHOWERS.
.OUTLOOK...
WED NIGHT-FRI...BUSY PATTERN WITH WAFFLING FRONTAL BOUNDARY
REMAINING IN THE VICINITY...AND WAVES OF SHRA PLUS ASSOCIATED
RESTRICTIONS MOVING ALONG IT. SLIGHT CHC TSRA AS WELL FRI.
SAT...MAINLY VFR BUT ISOLATED -SHRA STILL POSSIBLE OVER CENTRAL
NY.
SUN...VFR.
SUN...VFR.
.HYDROLOGY...
RIVERS WILL CONTINUE TO RUN HIGH AS WE CONTINUE THE GRADUAL SNOW
MELT RUN OFF FROM THE NORTH FACING SLOPES AND DEEP WOODS THIS
WEEK. THAT COUPLED WITH THESE PERIODIC EPISODES OF RAIN WILL HAVE
US FLIRT WITH A MINOR RIVER FLOOD POTENTIAL IN OUR MOST SENSITIVE
HEADWATER AREAS. AT THIS TIME...THE RAIN AMOUNTS IN THE MODELS
LOOK TOO ROBUST THROUGH THURSDAY...AS SEVERAL MODELS ARE OVER
PERFORMING WITH EVEN TODAY`S RAIN...BUT AS THE DEEPER SYSTEM OVER
THE UPPER MIDWEST WORKS EAST THIS WEEKEND IS WHEN WE WILL REALLY
NEED TO PAY ATTENTION AS THEN CONFIDENCE IN MORE RIVER POINTS
REACHING FLOOD STAGE MAY INCREASE. IN THE MEANTIME...THE NEXT 72
HOURS OR SO SHOULD BE OK WITH RIVERS RISING 3/4 TO NEAR BANKFULL
AT TIMES.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JAB
NEAR TERM...DJP
SHORT TERM...JAB
LONG TERM...PCF
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
447 AM EDT WED APR 8 2015
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTH INTO THE REGION LATE TODAY AND STALL
OVER THE AREA TONIGHT. THE FRONT WILL LIFT NORTH OF THE REGION
LATE THURSDAY. A COLD FRONT WILL APPROACH FROM THE WEST LATE
FRIDAY AND MOVE OFFSHORE SATURDAY MORNING. HIGH PRESSURE WILL
EXTEND OVER THE AREA FROM THE NORTH SATURDAY NIGHT AND SUNDAY. A
WARM FRONT WILL LIFT NORTH OF THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 400 AM WEDNESDAY...VERY DIFFICULT FORECAST NEXT 36 HOURS IN
TRYING TO PROVIDE DETAIL ON PRECIPITATION CHANCES IN THE MOIST
BUT WEAKLY FORCED ATMOSPHERE OVER THE CAROLINAS. ZONAL FLOW WILL
CONTINUE ALBEIT WITH RIDGING AND ASSOCIATED SUBTLE HEIGHT RISES
OVER THE SOUTHEAST STATES THROUGH THURSDAY. WEAK LOW AMPLITUDE MID
LEVEL WAVES IN THIS FLOW WILL HAVE THE POTENTIAL TO ENHANCE
PRECIPITATION CHANCES ESPECIALLY IF THE ORGANIZED CONVECTION
EXPECTED OVER THE PLAINS TODAY TRIGGERS A MCV WHICH WOULD THEN
MOVE EASTWARD TONIGHT. THE LARGE SCALE MODELS HAVE BEEN HAVING A
DIFFICULT TIME IN HANDLING THIS SITUATION SO HAVE A RELAYED ON THE
HRRR AND THE HIGH RESOLUTION NMM AND WRF MODELS TO TRY TO GET A
BETTER HANDLE ON THIS.
2 MAIN AREAS OF PRECIPITATION OCCURRING EARLY THIS MORNING. ONE
OVER THE COASTAL PLAIN AND ANOTHER MOVING INTO PIEDMONT. THE HRRR
MODEL BRINGS BOTH OF THESE AREAS ACROSS EASTERN NC TODAY MAINLY
THIS MORNING THEN INDICATES A LULL IN THE PRECIPITATION THIS
AFTERNOON. WILL BROADBRUSH THE FORECAST WITH 30-40% POPS DUE TO
INHERENT UNCERTAINTY ESPECIALLY THIS AFTERNOON WHEN THE ATMOSPHERE
BECOMES UNSTABLE AND A BACK DOOR COLD FRONT BEGINS TO DROP SOUTH
INTO NORTHERN PORTIONS OF THE AREA DURING PEAK HEATING.
TEMPERATURES WILL BE ABOVE NORMAL TODAY IN THE SOUTHERLY PRE
FRONTAL FLOW WITH HIGHS INLAND IN THE LOWER 80S AND LOWER 70S
BEACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 400 AM WEDNESDAY...THE BACK DOOR FRONT WILL SAG SOUTH TO
NEAR THE CRYSTAL COAST THEN STALL. STILL UNCERTAIN ON
PRECIPITATION DETAILS SO WILL FORECAST 30-50% POPS HIGHEST OUTER
BANKS. LOWS ARE FORECAST TO CONTINUE MILD WITH READINGS IN THE
UPPER 50S/LOWER 60S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 330 AM WEDNESDAY...00Z MODELS HAVE COME INTO BETTER
AGREEMENT WITH BACKDOOR FRONT STALLING OVER SRN SECTIONS LATE WED
NIGHT...THEN RETREATING NORTH ON THU. ECWMF AND GFS ALSO IN GOOD
AGREEMENT THAT STRONGER COLD FRONT WILL MOVE IN FRIDAY NIGHT AND
BE NEAR COAST SAT MORNING...THUS INCREASED POPS FRI NIGHT AND
DECREASED INLAND SAT.
THURSDAY AND THURSDAY NIGHT...SFC FRONT EXPECTED TO RETREAT NORTH
DURING THE DAY WITH WEAK RIDGING ALOFT. LACK OF UPR SUPPORT
EXPECTED TO LIMIT CONVECTIVE DEVELOPMENT BUT KEPT 20% POPS WITH
FRONT MOVING BACK NORTH. DID DROP POPS FOR THU NIGHT WITH MODELS
INDICATING PCPN THREAT WEST AND NORTH OF AREA. MOS GDNC CONTINUES
TO HAVE LARGE DIFFERENCES ON HIGH TEMPS WITH GFS COOLER AND NAM
WARMER DUE TO HANDLING OF FRONT. UPDATED PREVIOUS FCST WITH LEAN
TO COOLER GFS...HIGHS RANGING FROM AROUND 80 SOUTH TO 65-70 NORTH.
FRIDAY THROUGH SATURDAY...VERY WARM TEMPS EXPECTED FRIDAY AHEAD
OF A STRONGER COLD FRONT APPROACHING FRIDAY NIGHT. NO CHANGE TO
PREVIOUS THINKING FOR SHOWERS AND THUNDERSTORMS FRIDAY FOR INLAND
SECTIONS AS DECENT INSTABILITY AND UNIDIRECTIONAL WEST-SOUTHWEST
FLOW IS ENOUGH TO SUPPORT CHC POPS IN AFTERNOON INLAND OF SEA
BREEZE. LOW LEVEL THICKNESSES SUPPORT MID 80S FOR INLAND SECTIONS.
LATEST MODELS AGREE ON MAIN THREAT OF SHOWERS AND TSTMS ALONG AND
AHEAD OF COLD FRONT FRIDAY NIGHT...AND INCREASED POPS TO 60% ALL
ZONES...MAINLY FOR WRN HALF DURING EVENING AND ERN HALF OVERNIGHT.
CONCUR WITH SPC OUTLOOK OF SLIGHT RISK OF SVR WITH SUFFICIENT MID
LVL SHEAR TO SUPPORT ORGANIZED STRONG CONVECTION.
FRONT EXPECTED TO MOVE OFFSHORE SAT MORNING AND HAVE LOWERED POPS
TO INDICATE DRIER TREND. MAX TEMPS ABOUT 10 DEGS COOLER THAN
FRIDAY WITH MID 70S INLAND TO LOWER 60S NRN OBX.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...STRONG HIGH PRES WILL EXTEND
OVER AREA FROM NORTH SAT NIGHT AND SUNDAY AND GRADUALLY MOVE EAST
SUN NIGHT. DRY CONDITIONS EXPECTED WITH TEMPS NEAR NORMAL.
MONDAY INTO TUESDAY...NO CHANGE TO PREVIOUS FCST. HIGH PRES WILL
CONTINUE MOVING OFFSHORE WITH MOIST S TO SW FLOW RETURNING. SLIGHT
CHC POPS FOR SW HALF OF AREA MONDAY AND MON NIGHT...INCREASING TO
20-30% ALL AREAS TUESDAY. MAIN TEMP CHANGE WILL BE MIN TEMPS 10-15
DEGS ABOVE NORMAL MON NIGHT.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1245 AM WEDNESDAY...DIFFICULT FORECAST WITH CONVECTIVE
DEBRIS CLOUDS AND MIXING LIMITING RADIATIONAL COOLING AT
TIMES...AND PRECIPITATION APPROACHING THE TAF SITES FROM THE WEST.
THE PRECIPITATION WILL AFFECT ALL OF THE TAF SITES LATE TONIGHT
INTO WEDNESDAY MORNING ESPECIALLY KOAJ AND KEWN BUT SHOULD BE
MOSTLY LIGHT WITH BRIEF MVFR CONDITIONS. OUTSIDE OF THE
PRECIPITATION FORECAST SOUNDINGS INDICATED A SATURATED BOUNDARY
LAYER WHICH WILL LEAD TO FOG AND OR LOW STRATUS CLOUDS. NEW BERN
HAS DECOUPLED AS HAS RICHLANDS SO THESE AREAS HAVE THE BEST
POTENTIAL FOR IFR FOG OVERNIGHT AS THE GUIDANCE INDICATES THAT
KPGV AND KISO MAY REMAIN MIXED. HOWEVER THE HRRR AND NARRE
GUIDANCE IS INDICATING IFR CEILINGS ALL TAF SITES BY 09Z SO
EXPECTING POOR CONDITIONS OVERNIGHT EARLY WEDNESDAY FOR AT LEAST
SEVERAL HOURS AT ALL OF THE TAF SITES. CONDITIONS SHOULD IMPROVE
TO VFR LATE WEDNESDAY MORNING AND AFTERNOON OUTSIDE OF ANY
SCATTERED SHOWER/THUNDERSTORM ACTIVITY THAT DEVELOPS. GUIDANCE IS
AGAIN POINTING TO THE POTENTIAL FOR IFR CONDITIONS REDEVELOPING
AGAIN WEDNESDAY EVENING AS THE BL REMAINS SATURATED.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 400 AM WEDNESDAY...SOME LOWER CIGS COULD PERSIST THURS
MORNING WITH LOW LEVEL NE FLOW. VFR MAINLY EXPECTED THURS NIGHT
INTO FRIDAY...THEN HIGHER THREAT OF SUB-VFR CONDITIONS FRI NIGHT
INTO EARLY SAT WITH GOOD COVERAGE OF SHOWERS AND TSTMS EXPECTED
AS STRONGER FRONT MOVES INTO AREA. GUSTY SW WINDS 15-25 MPH LIKELY
FRIDAY AHEAD OF FRONT. HIGH PRESSURE WILL ALLOW AVIATION
CONDITIONS TO IMPROVE TO VFR SATURDAY EVENING THROUGH SUNDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 400 AM WEDNESDAY...WINDS WILL REMAIN 15 KT OR LESS THROUGH
TONIGHT. THE MAIN FEATURE WILL BE A BACK DOOR COLD FRONT WHICH IS
FORECAST TO PUSH SOUTH INTO THE NORTHERN WATERS/ALBEMARLE SOUND
LATE TODAY THEN CONTINUE SOUTH TONIGHT INTO THE CENTRAL
WATERS/PAMLICO SOUND WHERE IT WILL SATLL. EXPECT WINDS TO VEER
FROM SOUTHERLY THIS MORNING TO SOUTHWEST TO WEST THIS AFTERNOON
THEN TO NORTH AND NORTHEAST BEHIND THE FRONT LATE TODAY AND
TONIGHT. SEAS WILL REMAIN IN THE 2-4 FT RANGE THROUGH THE PERIOD.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 400 AM WEDNESDAY...CONTINUED PREVIOUS FCST THINKING WITH
WINDS GRADUALLY RETURNING TO S-SW DURING THE DAY THU AS FRONT
RETREATS BACK NORTH. MAIN CHANGE WAS TO INDICATE FASTER COLD FRONT
PASSAGE SAT MORNING WITH LATEST MODELS IN GOOD AGREEMENT. STILL
EXPECT STRONGEST WINDS FRI AND FRI NIGHT AHEAD OF FRONT...SW
15-25 KT WITH SEAS BUILDING TO SMALL CRAFT ADVISORY LEVELS FRI
AFTN INTO EARLY SAT. NE SURGE 10-20 KT EXPECTED LATE SAT THROUGH
SUNDAY. ADJUSTED SEAS WITH LATEST NWPS. HEIGHTS MAINLY 3-4 FT
THU...BUILDING TO 4-6 FT FRI-FRI NIGHT...THEN DIMINISHING 2-4 FT
SUNDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JME
NEAR TERM...JME
SHORT TERM...JME
LONG TERM...JBM
AVIATION...JME/JBM
MARINE...JME/JBM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
330 AM EDT WED APR 8 2015
.SYNOPSIS...A MOIST AIR MASS AND SOUTHERLY FLOW WILL PERSIST OVER
THE REGION TODAY THROUGH TONIGHT. A BACKDOOR COLD FRONT WILL DROP
INTO NORTHEAST NORTH CAROLINA FROM THE NORTH LATE TONIGHT... THEN
LIFT BACK NORTH LATE THURSDAY. A COLD FRONT WILL APPROACH THE REGION
LATE FRIDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 315 AM WEDNESDAY...
TOUGH FORECAST THIS MORNING TRYING TO PINPOINT THE DETAILS OF
EXPECTED CONVECTION. LATEST SURFACE ANALYSIS SHOWS A PROMINENT COLD
FRONT FROM NRN OK THROUGH NRN MO... WITH A MORE DIFFUSE FRONTAL ZONE
EXTENDING ACROSS IL AND THE OH VALLEY THEN SOUTHEAST THROUGH NRN/ERN
VA. ISOLATED BUT STRONG AND ORGANIZED CONVECTION OVER SC INTO SE NC
EARLIER TONIGHT IS EXITING BUT ADDITIONAL LESS-ORGANIZED SHOWERS AND
ISOLATED STORMS ARE CLOSE BEHIND... THE DYING REMNANTS OF AN EARLIER
MATURE COMPLEX THAT CROSSED KY LAST EVENING. THIS HAS MANIFESTED
INTO A WEAK MCV THAT CAN BE DISCERNED IN RADAR AND WATER VAPOR
IMAGERY CENTERED OVER WEST CENTRAL VA. THE LAST FEW HRRR MODEL RUNS
REFLECTED BOTH OF THESE FEATURES BETTER THAN THE LARGER-SCALE MODELS
WITH PARAMETERIZED CONVECTION (NOT A SURPRISE)... AND HAVE LARGELY
FOLLOWED THIS SOLUTION FOR THE NEXT 12 HRS OR SO. EXPECT SCATTERED
SHOWERS AND A FEW STORMS THROUGH MID MORNING... WITH THE BEST CHANCE
SHIFTING TO NRN/ERN CWA NEAR AND SOON AFTER SUNRISE. WE SHOULD THEN
SEE A PERIOD OF RELATIVE SUBSIDENCE FROM ROUGHLY LATE MORNING
THROUGH MID AFTERNOON... AS THE VA MCV SHIFTS OFF THE COAST INDUCING
SURFACE LOW FORMATION ALONG THE WEAK FRONTAL ZONE. AS THIS OCCURS...
THE NORTHEAST FLOW ON THE BACKSIDE OF THIS LOW SHOULD HELP DRAW THE
FRONTAL ZONE SOUTHWARD INTO NORTH CENTRAL/NE NC. THE LAST SEVERAL
GFS RUNS HAVE TAKEN THIS FRONT MUCH FURTHER INTO NC THAN THE OTHER
MODEL SOLUTIONS. WHILE THERE IS A CHILLY SURFACE HIGH CENTERED OVER
QUEBEC NOSING SOUTHWARD OVER THE NORTHEAST STATES INTO THE NRN
MIDATLANTIC REGION... THIS LOOKS TO BE CENTERED TOO FAR NORTH TO
HAVE MUCH INFLUENCE ON THE FRONT THIS FAR SOUTH. EXPECT A WIND SHIFT
TO NORTHEASTERLY OVER THE NE CWA WITH SLIGHTLY COOLER TEMPS MOVING
IN LATE TODAY INTO TONIGHT... BUT THE COOLING SHOULDN`T BE THAT
EXTREME. WILL FORECAST HIGHS TODAY IN THE LOW-MID 80S EXCEPT FOR MID-
UPPER 70S IN THE FAR NE. ATTENTION THEN TURNS TO THE CONVECTION NOW
ALONG THE FRONT OVER KS/MO/IA/IL AND THE POTENTIAL FOR ITS RESULTING
MCV TO MOVE ESE ALONG THE FRONTAL ZONE INTO OUR REGION LATE TODAY
INTO TONIGHT. THE GFS HINTS AT THIS... SHOWING SPOTTY MID LEVEL
VORTICITY MAXIMA (LOOKING LIKE CONVECTIVE FEEDBACK) MOVING TO THE
CENTRAL/SRN APPALACHIANS LATE TODAY INTO TONIGHT. IT MAKES SENSE
THAT THIS WOULD TRIGGER CONVECTION ALONG AND EAST OF THE MOUNTAINS
WHERE MODELS INDICATE MUCAPE OF 1500-2500 J/KG IN THE 21Z-06Z TIME
FRAME WITH DEEP LAYER BULK SHEAR AROUND 30 KTS... STILL RATHER
MODEST BUT ENOUGH TO SUSTAIN CONVECTION AS THE COLD POOL TRACKS ESE
THROUGH NRN/ERN NC. WILL SHOW A PERIOD OF LOW POPS THROUGH MID
AFTERNOON... FOLLOWED BY A RISE TO SCATTERED SHOWERS/STORMS LATE
AFTERNOON THROUGH THIS EVENING... TRENDING DOWN OVERNIGHT AS THIS
PERTURBATION EXITS TO OUR EAST. WITH THE FRONT STILL EXPECTED TO BE
SITTING OVER THE NE CWA OVERNIGHT... WILL HAVE LOWS IN THE 60-65
RANGE EXCEPT FOR MID-UPPER 50S NE. -GIH
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM WEDNESDAY...
STRONG SURFACE LOW PRESSURE OVER THE CO/KS BORDER TODAY WILL REMAIN
STRONG AS TRACKS ALONG THE FRONT TO SRN WI LATE THU AND NEAR SAULT
STE MARIE BY DAYBREAK FRI. THE FRONTAL ZONE MEANWHILE BY LATE THU
WILL EXTEND ACROSS SRN MI DOWN THROUGH WRN PA/VA THEN EASTWARD ALONG
THE ERN VA/NC BORDER AREA. THE NAM/GFS SHOW DESTABILIZATION THU
AFTERNOON INTO EARLY EVENING (THE NAM MORESO THAN THE GFS)
ESPECIALLY OVER THE SW CWA SW OF THE FRONT WITH MUCAPE EXCEEDING
1500 J/KG... HOWEVER THE DEEP LAYER BULK SHEAR DECREASES TO LESS
THAN 25 KTS... A REFLECTION OF THE DIGGING ENERGY OVER THE MIDWEST
(LEADING TO THE STRONG SURFACE LOW) PROMPTING RISING HEIGHTS AND
REDUCED MID LEVEL WINDS OVER THE CAROLINAS/SOUTHEAST STATES... AND
THIS SHOULD REDUCE THE PROBABILITY FOR ANY STRONG TO SEVERE STORMS.
WILL BRING IN CHANCE POPS FOR SHOWERS AND STORMS... FOCUSED MAINLY
OVER THE NW HALF OF THE CWA... PEAKING DURING THE AFTERNOON INTO
EARLY EVENING. EXPECT HIGHS FROM THE MID 70S NE TO LOWER 80S SW.
WARM LOWS THU NIGHT IN THE MID 60S... WHICH WILL APPROACH RECORD
HIGH MINIMUMS FOR APRIL 10TH. -GIH
&&
LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 230 AM WEDNESDAY...
THERE IS GROWING CONFIDENCE WITH REGARD TO A FRONTAL SYSTEM THAT IS
PROGGED TO MOVE ACROSS THE CAROLINAS ON FRIDAY EVENING THROUGH
SATURDAY MORNING. THIS WILL BE FOLLOWED BY WEAK RIDGING ALOFT AND
SURFACE HIGH PRESSURE OVER THE MID ATLANTIC THROUGH THE WEEKEND.
CONFIDENCE IN THE FORECAST TAKES A BIG TURN FOR THE WORSE BEGINNING
ON MONDAY AS MODEL SOLUTIONS DIVERGE CONSIDERABLY. ABOUT THE ONLY
THING THEY AGREE ON AT THIS POINT IS SOME KIND OF UPPER RIDGING OVER
THE SOUTHEAST BUT EVEN THE POSITION AND TIMING OF THAT IS IN
QUESTION AT THIS TIME. THE PROBLEMS EARLY NEXT WEEK STEM FROM A
CUTOFF UPPER LEVEL LOW OVER TEXAS THAT FUNNELS MOISTURE OUT OF THE
GULF AND OVER THE DEEP SOUTH BUT THERE ARE MASSIVE QUESTIONS IN
TIMING AS THE ECMWF SOLUTION HAS PRECIPITATION REACHING CENTRAL NC
BY MONDAY AFTERNOON AND THE GFS DOESN`T HAVE ANYTHING MEASURABLE
OVER THE CWA UNTIL THURSDAY NIGHT. THAT QUALIFIES AS AN EXTREMELY
LOW CONFIDENCE FORECAST AND WILL BE HANDLED AS SUCH. THEREFORE WILL
MAINTAIN CHANCE POPS FROM MONDAY THROUGH THE END OF THE PERIOD.
SHIFTING THE CONVERSATION FROM WHAT WE DON`T KNOW TO MORE OF WHAT WE
DO KNOW REGARDING THE FRONTAL SYSTEM ON FRIDAY...SPC STILL HAS AN
AREA OF 15% RISK OF SEVERE STORMS OVER ALL OF CENTRAL NC. AFTER A
CLOSER LOOK AT THE FORECAST SOUNDINGS ON FRIDAY AFTERNOON...STORMS
WILL BE INSTABILITY DRIVEN WITH THE SOUTHEASTERN PART OF THE CWA
MOST LIKELY TO SEE STRONGER STORM ACTIVITY BUT THE POSSIBILITY WILL
REMAIN EVERYWHERE. THE KFAY MODEL SOUNDINGS SHOW JUST OVER 1100 J/KG
OF SURFACE BASED CAPE WITH 500 J/KG OCCURRING WITHIN THE HAIL GROWTH
ZONE. THE HAIL THREAT LOOKS BETTER THAN THE WIND THREAT AT THIS TIME
AS SHEAR IS MEAGER...ESPECIALLY IN THE LOW LEVELS. SOME INVERTED V
SIGNATURES IN THE SOUNDING AND SOME RELATIVE DRYING AT THE 700 MB
LEVEL COULD INCREASE THE POTENTIAL FOR SOME WET MICROBURSTS BUT
OVERALL THE ENVIRONMENT FOR WIND OUTSIDE OF A LARGER HAIL CORE
COLLAPSING IS LESS FAVORABLE AND VERY LOW AMOUNTS OF HELICITY
SUGGEST TORNADOES WILL NOT BE LIKELY EITHER. OVERALL FEELING IS THAT
SOME STRONGER STORMS WILL POP UP FRIDAY AFTERNOON BUT ANY SEVERE
WILL BE FAIRLY ISOLATED. WORTH WATCHING TO SEE HOW IT EVOLVES OVER
THE NEXT COUPLE OF DAYS. CONVECTION SHOULD PRODUCE DECENT QPF VALUES
IN THE RANGE OF A QUARTER TO THREE QUARTERS OF AN INCH. PW VALUES
ARE OVER AN INCH AND A HALF.
FRIDAY WILL BE THE WARMEST DAY AHEAD OF THE FRONT WITH HIGHS IN THE
MID 80S AND THEN TEMPS WILL COOL OFF AFTER THE FRONT PASSES WITH
HIGH PRESSURE BRINGING IN COOL AIR FROM THE NORTH. EXPECT MOSTLY LOW
TO MID 70S FOR HIGHS FOR THE REMAINDER OF THE PERIOD AFTER FRIDAY.
LOWS IN THE LOWER 50S TO MID 60S.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 110 AM WEDNESDAY...
PRIMARY AVIATION CONCERN NEXT 24 HRS: CHANCE OF MVFR OR IFR CIGS NOW
THROUGH MID MORNING WITH A FEW SHOWERS AND POSSIBLE ISOLATED STORMS.
CONFIDENCE IS LOWER THAN USUAL REGARDING THE FORECAST THROUGH THIS
MORNING. A VERY MOIST AIR MASS REMAINS IN PLACE FROM THE SURFACE UP
THROUGH THE MID LEVELS (ABOVE 15 000 FT). FLIGHT CATEGORIES ARE
LIKELY TO WAVER AMONG MVFR... IFR... AND VFR THIS MORNING... HOWEVER
EXPECT VFR CONDITIONS TO OCCUR MOST OF THE TIME THROUGH MID MORNING.
AVIATORS SHOULD REMAIN ALERT FOR POCKETS OF SUB-VFR CIGS... AS THEY
ARE LIKELY TO HAPPEN BUT DIFFICULT TO PINPOINT. SCATTERED SHOWERS
WILL AFFECT CENTRAL NC THROUGH THE FIRST 6-9 HRS OF THE TAF VALID
PERIOD... BUT VSBYS SHOULD REMAIN MAINLY VFR WITH THESE... ONLY
BRIEFLY DROPPING TO MVFR FOR LESS THAN A HALF HOUR AT A TIME. MODELS
HAVE HAD DIFFICULTY WITH RECENT AND CURRENT CONDITIONS HERE AND
UPSTREAM... BUT ALL AGREE ON A HIGH PROBABILITY OF VFR CONDITIONS
FROM LATE MORNING THROUGH THE DAY... WITH VERY FEW IF ANY
SHOWERS/STORMS AS WE SHOULD BE IN A RELATIVE LULL PERIOD BETWEEN
CONVECTIVE SYSTEMS. A COUPLE OF MODELS HINT AT MORE STORMS ROLLING
OVER THE CENTRAL/SRN APPALACHIANS THIS EVENING AND POTENTIALLY
AFFECTING INT/GSO/RDU TOWARD THE END OF THE TAF VALID PERIOD WITH
BRIEF SUB-VFR CIGS/VSBYS AND GUSTY WINDS... HOWEVER CONFIDENCE IS
NOT HIGH ENOUGH IN THE LOCATION AND TIMING OF ANY SUCH SYSTEM TO
INCLUDE IN THE TAFS AT THIS TIME. WILL CONTINUE TO MONITOR.
LOOKING BEYOND 06Z EARLY THU MORNING... MAY NEED TO INCLUDE A CHANCE
FOR SUB-VFR SHOWERS/STORMS INTO THE OVERNIGHT HOURS. OTHERWISE... WE
SHOULD SEE AREAS OF LOW CLOUDS AND FOG DEVELOP ESPECIALLY AFFECTING
RDU/RWI AS A BACKDOOR FRONT DROPS SOUTHWARD INTO THE NORTHEAST
PORTION OF CENTRAL NC... WITH LIGHT SURFACE WINDS SHIFTING AROUND TO
NORTHEASTERLY. ANY LOW CLOUDS SHOULD LIFT TO VFR THU MORNING...
REMAINING VFR THROUGH THU EVENING WITH A FEW SHOWERS/STORMS POSSIBLE
THU AFTERNOON. AN APPROACHING COLD FRONT ON FRIDAY WILL BRING A GOOD
CHANCE OF SUB-VFR CONDITIONS WITHIN SHOWERS AND STORMS FRI AFTERNOON
AND EVENING. VFR CIGS/VSBYS ARE EXPECTED BEHIND THE FRONT LATE FRI
NIGHT THROUGH SUN AS HIGH PRESSURE BUILDS IN. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 AM EDT WED APR 8 2015
.SYNOPSIS...A MOIST AIR MASS AND SOUTHERLY FLOW WILL PERSIST OVER
THE REGION TODAY THROUGH TONIGHT. A BACKDOOR COLD FRONT WILL DROP
INTO NORTHEAST NORTH CAROLINA FROM THE NORTH LATE TONIGHT... THEN
LIFT BACK NORTH LATE THURSDAY. A COLD FRONT WILL APPROACH THE REGION
LATE FRIDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 315 AM WEDNESDAY...
TOUGH FORECAST THIS MORNING TRYING TO PINPOINT THE DETAILS OF
EXPECTED CONVECTION. LATEST SURFACE ANALYSIS SHOWS A PROMINENT COLD
FRONT FROM NRN OK THROUGH NRN MO... WITH A MORE DIFFUSE FRONTAL ZONE
EXTENDING ACROSS IL AND THE OH VALLEY THEN SOUTHEAST THROUGH NRN/ERN
VA. ISOLATED BUT STRONG AND ORGANIZED CONVECTION OVER SC INTO SE NC
EARLIER TONIGHT IS EXITING BUT ADDITIONAL LESS-ORGANIZED SHOWERS AND
ISOLATED STORMS ARE CLOSE BEHIND... THE DYING REMNANTS OF AN EARLIER
MATURE COMPLEX THAT CROSSED KY LAST EVENING. THIS HAS MANIFESTED
INTO A WEAK MCV THAT CAN BE DISCERNED IN RADAR AND WATER VAPOR
IMAGERY CENTERED OVER WEST CENTRAL VA. THE LAST FEW HRRR MODEL RUNS
REFLECTED BOTH OF THESE FEATURES BETTER THAN THE LARGER-SCALE MODELS
WITH PARAMETERIZED CONVECTION (NOT A SURPRISE)... AND HAVE LARGELY
FOLLOWED THIS SOLUTION FOR THE NEXT 12 HRS OR SO. EXPECT SCATTERED
SHOWERS AND A FEW STORMS THROUGH MID MORNING... WITH THE BEST CHANCE
SHIFTING TO NRN/ERN CWA NEAR AND SOON AFTER SUNRISE. WE SHOULD THEN
SEE A PERIOD OF RELATIVE SUBSIDENCE FROM ROUGHLY LATE MORNING
THROUGH MID AFTERNOON... AS THE VA MCV SHIFTS OFF THE COAST INDUCING
SURFACE LOW FORMATION ALONG THE WEAK FRONTAL ZONE. AS THIS OCCURS...
THE NORTHEAST FLOW ON THE BACKSIDE OF THIS LOW SHOULD HELP DRAW THE
FRONTAL ZONE SOUTHWARD INTO NORTH CENTRAL/NE NC. THE LAST SEVERAL
GFS RUNS HAVE TAKEN THIS FRONT MUCH FURTHER INTO NC THAN THE OTHER
MODEL SOLUTIONS. WHILE THERE IS A CHILLY SURFACE HIGH CENTERED OVER
QUEBEC NOSING SOUTHWARD OVER THE NORTHEAST STATES INTO THE NRN
MIDATLANTIC REGION... THIS LOOKS TO BE CENTERED TOO FAR NORTH TO
HAVE MUCH INFLUENCE ON THE FRONT THIS FAR SOUTH. EXPECT A WIND SHIFT
TO NORTHEASTERLY OVER THE NE CWA WITH SLIGHTLY COOLER TEMPS MOVING
IN LATE TODAY INTO TONIGHT... BUT THE COOLING SHOULDN`T BE THAT
EXTREME. WILL FORECAST HIGHS TODAY IN THE LOW-MID 80S EXCEPT FOR MID-
UPPER 70S IN THE FAR NE. ATTENTION THEN TURNS TO THE CONVECTION NOW
ALONG THE FRONT OVER KS/MO/IA/IL AND THE POTENTIAL FOR ITS RESULTING
MCV TO MOVE ESE ALONG THE FRONTAL ZONE INTO OUR REGION LATE TODAY
INTO TONIGHT. THE GFS HINTS AT THIS... SHOWING SPOTTY MID LEVEL
VORTICITY MAXIMA (LOOKING LIKE CONVECTIVE FEEDBACK) MOVING TO THE
CENTRAL/SRN APPALACHIANS LATE TODAY INTO TONIGHT. IT MAKES SENSE
THAT THIS WOULD TRIGGER CONVECTION ALONG AND EAST OF THE MOUNTAINS
WHERE MODELS INDICATE MUCAPE OF 1500-2500 J/KG IN THE 21Z-06Z TIME
FRAME WITH DEEP LAYER BULK SHEAR AROUND 30 KTS... STILL RATHER
MODEST BUT ENOUGH TO SUSTAIN CONVECTION AS THE COLD POOL TRACKS ESE
THROUGH NRN/ERN NC. WILL SHOW A PERIOD OF LOW POPS THROUGH MID
AFTERNOON... FOLLOWED BY A RISE TO SCATTERED SHOWERS/STORMS LATE
AFTERNOON THROUGH THIS EVENING... TRENDING DOWN OVERNIGHT AS THIS
PERTURBATION EXITS TO OUR EAST. WITH THE FRONT STILL EXPECTED TO BE
SITTING OVER THE NE CWA OVERNIGHT... WILL HAVE LOWS IN THE 60-65
RANGE EXCEPT FOR MID-UPPER 50S NE. -GIH
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 220 PM TUESDAY...
THE WEST-CENTRAL UNITED STATES TROUGH AND UPPER RIDGING OVER THE
SOUTH ATLANTIC STATES WILL GENERATE WARMTH THURSDAY INTO FRIDAY WITH
A CHANCE OF SHOWERS AND THUNDERSTORMS LATE FRIDAY INTO FRIDAY NIGHT.
THE MID/UPPER TROUGH IS FORECAST TO MOVE EAST AND BRING AN ACTIVE
COLD FRONT ACROSS THE APPALACHIANS LATE FRIDAY. HOWEVER... THE
SYSTEM IS FORECAST TO BE IN A WEAKENING MODE AS IT PUSHES EAST OF
THE MOUNTAINS RESULTING IN LESS IN THE WAY OF A SEVERE WEATHER
THREAT OVER OUR REGION AS OPPOSED TO WEST OF THE MOUNTAINS. THE
FRONT WILL PUSH OFFSHORE BY SATURDAY LATE AND THIS WILL DECREASE THE
CHANCE OF SHOWERS WITH A BRIEF PERIOD OF TRANQUIL WEATHER EXPECTED
SUNDAY INTO MONDAY. A RETURN TO STORMY WEATHER IS EXPECTED
ESPECIALLY BY MONDAY NIGHT AND TUESDAY AS YET ANOTHER SYSTEM IS
FORECAST TO DEVELOP OVER THE MID MISSISSIPPI VALLEY PULLING GULF
MOISTURE AND A WARM FRONT INTO THE TENNESSEE VALLEY AND MID ATLANTIC
REGION.
THURSDAY AND FRIDAY SHOULD BE THE WARMEST DAYS WITH HIGHS 80-85 AND
LOWS IN THE 60S. THE CHANCE OF SHOWERS AND THUNDERSTORMS WILL
INCREASE FRIDAY INTO FRIDAY NIGHT WITH THE COLD FRONT APPROACHING.
THERE IS A CHANCE OF SHOWERS... MAINLY IN THE SOUTH AND EAST
SATURDAY MORNING... OTHERWISE DRIER AND COOLER WEATHER IS EXPECTED
LATER SATURDAY THROUGH SUNDAY. LOWS IN THE 50S. HIGHS IN THE LOWER O
MID 70S. THERE IS A CHANCE OF SHOWERS AGAIN LATE MONDAY INTO TUESDAY
WITH WARMER TEMPERATURES. -BV
&&
LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 230 AM WEDNESDAY...
THERE IS GROWING CONFIDENCE WITH REGARD TO A FRONTAL SYSTEM THAT IS
PROGGED TO MOVE ACROSS THE CAROLINAS ON FRIDAY EVENING THROUGH
SATURDAY MORNING. THIS WILL BE FOLLOWED BY WEAK RIDGING ALOFT AND
SURFACE HIGH PRESSURE OVER THE MID ATLANTIC THROUGH THE WEEKEND.
CONFIDENCE IN THE FORECAST TAKES A BIG TURN FOR THE WORSE BEGINNING
ON MONDAY AS MODEL SOLUTIONS DIVERGE CONSIDERABLY. ABOUT THE ONLY
THING THEY AGREE ON AT THIS POINT IS SOME KIND OF UPPER RIDGING OVER
THE SOUTHEAST BUT EVEN THE POSITION AND TIMING OF THAT IS IN
QUESTION AT THIS TIME. THE PROBLEMS EARLY NEXT WEEK STEM FROM A
CUTOFF UPPER LEVEL LOW OVER TEXAS THAT FUNNELS MOISTURE OUT OF THE
GULF AND OVER THE DEEP SOUTH BUT THERE ARE MASSIVE QUESTIONS IN
TIMING AS THE ECMWF SOLUTION HAS PRECIPITATION REACHING CENTRAL NC
BY MONDAY AFTERNOON AND THE GFS DOESN`T HAVE ANYTHING MEASURABLE
OVER THE CWA UNTIL THURSDAY NIGHT. THAT QUALIFIES AS AN EXTREMELY
LOW CONFIDENCE FORECAST AND WILL BE HANDLED AS SUCH. THEREFORE WILL
MAINTAIN CHANCE POPS FROM MONDAY THROUGH THE END OF THE PERIOD.
SHIFTING THE CONVERSATION FROM WHAT WE DON`T KNOW TO MORE OF WHAT WE
DO KNOW REGARDING THE FRONTAL SYSTEM ON FRIDAY...SPC STILL HAS AN
AREA OF 15% RISK OF SEVERE STORMS OVER ALL OF CENTRAL NC. AFTER A
CLOSER LOOK AT THE FORECAST SOUNDINGS ON FRIDAY AFTERNOON...STORMS
WILL BE INSTABILITY DRIVEN WITH THE SOUTHEASTERN PART OF THE CWA
MOST LIKELY TO SEE STRONGER STORM ACTIVITY BUT THE POSSIBILITY WILL
REMAIN EVERYWHERE. THE KFAY MODEL SOUNDINGS SHOW JUST OVER 1100 J/KG
OF SURFACE BASED CAPE WITH 500 J/KG OCCURRING WITHIN THE HAIL GROWTH
ZONE. THE HAIL THREAT LOOKS BETTER THAN THE WIND THREAT AT THIS TIME
AS SHEAR IS MEAGER...ESPECIALLY IN THE LOW LEVELS. SOME INVERTED V
SIGNATURES IN THE SOUNDING AND SOME RELATIVE DRYING AT THE 700 MB
LEVEL COULD INCREASE THE POTENTIAL FOR SOME WET MICROBURSTS BUT
OVERALL THE ENVIRONMENT FOR WIND OUTSIDE OF A LARGER HAIL CORE
COLLAPSING IS LESS FAVORABLE AND VERY LOW AMOUNTS OF HELICITY
SUGGEST TORNADOES WILL NOT BE LIKELY EITHER. OVERALL FEELING IS THAT
SOME STRONGER STORMS WILL POP UP FRIDAY AFTERNOON BUT ANY SEVERE
WILL BE FAIRLY ISOLATED. WORTH WATCHING TO SEE HOW IT EVOLVES OVER
THE NEXT COUPLE OF DAYS. CONVECTION SHOULD PRODUCE DECENT QPF VALUES
IN THE RANGE OF A QUARTER TO THREE QUARTERS OF AN INCH. PW VALUES
ARE OVER AN INCH AND A HALF.
FRIDAY WILL BE THE WARMEST DAY AHEAD OF THE FRONT WITH HIGHS IN THE
MID 80S AND THEN TEMPS WILL COOL OFF AFTER THE FRONT PASSES WITH
HIGH PRESSURE BRINGING IN COOL AIR FROM THE NORTH. EXPECT MOSTLY LOW
TO MID 70S FOR HIGHS FOR THE REMAINDER OF THE PERIOD AFTER FRIDAY.
LOWS IN THE LOWER 50S TO MID 60S.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 110 AM WEDNESDAY...
PRIMARY AVIATION CONCERN NEXT 24 HRS: CHANCE OF MVFR OR IFR CIGS NOW
THROUGH MID MORNING WITH A FEW SHOWERS AND POSSIBLE ISOLATED STORMS.
CONFIDENCE IS LOWER THAN USUAL REGARDING THE FORECAST THROUGH THIS
MORNING. A VERY MOIST AIR MASS REMAINS IN PLACE FROM THE SURFACE UP
THROUGH THE MID LEVELS (ABOVE 15 000 FT). FLIGHT CATEGORIES ARE
LIKELY TO WAVER AMONG MVFR... IFR... AND VFR THIS MORNING... HOWEVER
EXPECT VFR CONDITIONS TO OCCUR MOST OF THE TIME THROUGH MID MORNING.
AVIATORS SHOULD REMAIN ALERT FOR POCKETS OF SUB-VFR CIGS... AS THEY
ARE LIKELY TO HAPPEN BUT DIFFICULT TO PINPOINT. SCATTERED SHOWERS
WILL AFFECT CENTRAL NC THROUGH THE FIRST 6-9 HRS OF THE TAF VALID
PERIOD... BUT VSBYS SHOULD REMAIN MAINLY VFR WITH THESE... ONLY
BRIEFLY DROPPING TO MVFR FOR LESS THAN A HALF HOUR AT A TIME. MODELS
HAVE HAD DIFFICULTY WITH RECENT AND CURRENT CONDITIONS HERE AND
UPSTREAM... BUT ALL AGREE ON A HIGH PROBABILITY OF VFR CONDITIONS
FROM LATE MORNING THROUGH THE DAY... WITH VERY FEW IF ANY
SHOWERS/STORMS AS WE SHOULD BE IN A RELATIVE LULL PERIOD BETWEEN
CONVECTIVE SYSTEMS. A COUPLE OF MODELS HINT AT MORE STORMS ROLLING
OVER THE CENTRAL/SRN APPALACHIANS THIS EVENING AND POTENTIALLY
AFFECTING INT/GSO/RDU TOWARD THE END OF THE TAF VALID PERIOD WITH
BRIEF SUB-VFR CIGS/VSBYS AND GUSTY WINDS... HOWEVER CONFIDENCE IS
NOT HIGH ENOUGH IN THE LOCATION AND TIMING OF ANY SUCH SYSTEM TO
INCLUDE IN THE TAFS AT THIS TIME. WILL CONTINUE TO MONITOR.
LOOKING BEYOND 06Z EARLY THU MORNING... MAY NEED TO INCLUDE A CHANCE
FOR SUB-VFR SHOWERS/STORMS INTO THE OVERNIGHT HOURS. OTHERWISE... WE
SHOULD SEE AREAS OF LOW CLOUDS AND FOG DEVELOP ESPECIALLY AFFECTING
RDU/RWI AS A BACKDOOR FRONT DROPS SOUTHWARD INTO THE NORTHEAST
PORTION OF CENTRAL NC... WITH LIGHT SURFACE WINDS SHIFTING AROUND TO
NORTHEASTERLY. ANY LOW CLOUDS SHOULD LIFT TO VFR THU MORNING...
REMAINING VFR THROUGH THU EVENING WITH A FEW SHOWERS/STORMS POSSIBLE
THU AFTERNOON. AN APPROACHING COLD FRONT ON FRIDAY WILL BRING A GOOD
CHANCE OF SUB-VFR CONDITIONS WITHIN SHOWERS AND STORMS FRI AFTERNOON
AND EVENING. VFR CIGS/VSBYS ARE EXPECTED BEHIND THE FRONT LATE FRI
NIGHT THROUGH SUN AS HIGH PRESSURE BUILDS IN. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...VINCENT
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1250 AM EDT WED APR 8 2015
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE OFFSHORE THROUGH MIDWEEK. A COLD
FRONT WILL PUSH SOUTH INTO THE REGION LATE WEDNESDAY AND STALL
OVER THE AREA THROUGH EARLY THURSDAY. THE FRONT WILL LIFT NORTH
OF THE REGION THURSDAY NIGHT AND FRIDAY. A COLD FRONT WILL
APPROACH FROM THE WEST FRIDAY NIGHT. THE FRONT WILL CROSS EASTERN
NC SATURDAY THEN STALL SOUTH OF THE AREA SUNDAY INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1245 AM WEDNESDAY...NORTHERN FRINGE OF PRECIPITATION AREA
OVER SOUTH CAROLINA EXTENDS NORTH INTO OUR COASTAL PLAIN COUNTIES
LATE TONIGHT. BASED ON TRENDS IN THE RADAR WITH ACTIVITY HOLDING
TOGETHER AND LATEST HRRR MODEL RUN WHICH TAKES THE PRECIPITATION
SLOWLY EAST ACROSS THE REGION THROUGH THE MORNING HOURS HAVE
DECIDED TO INCREASE POPS TO LIKELY ALONG AND SOUTH OF THE HIGHWAY
70 CORRIDOR WITH CHANCE POPS ELSEWHERE. LOW AMPLITUDE SHORTWAVES
WILL CONTINUE TO TRAVERSE THE AREA DURING THE NEXT 24-36 HOURS
ENHANCING PRECIPITATION AS THEY CROSS THE REGION. MILD TEMPS
EXPECTED WITH LOWS IN THE UPPER 50S/LOWER 60S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM THURSDAY/...
AS OF 255 PM TUESDAY...CONTINUED PREVIOUS FCST INDICATING A WEAK
BACK DOOR FRONT PUSHING S INTO NERN SXNS LATE WED. EXPECT THERE
WILL BE ENOUGH MOISTURE LIFT AND INSTABILITY FOR SCT SHRA/TSRA
AWAY FROM THE COAST DURING MAX HEATING. TEMPS WARM FROM THE LOWER
80S INLAND TO LOWER 70S COAST.
&&
.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
AS OF 355 PM TUESDAY...SOME DIFFERENCES EXIST BETWEEN THE 12Z
GUIDANCE WITH REGARDS TO THE BACKDOOR COLD FRONT MOVING SOUTH INTO
EASTERN NC WEDNESDAY EVENING INTO WEDNESDAY NIGHT. WEAK ZONAL FLOW
ALOFT WED NIGHT. GUIDANCE NOW SUGGESTS THE FRONT WILL STRUGGLE TO
REACH SOUTHERN ZONES AND HAVE INDICATED THIS TREND IN WINDS
FORECAST. MAINTAINED LOW CHANCE TO SLIGHT CHANCE POPS WEDNESDAY
NIGHT INTO THURSDAY AND KEPT MENTION OF THUNDERSTORMS FOR SOUTHERN
ZONES/COAST THURSDAY DUE TO WEAK INSTABILITY NOTED IN FORECAST
SOUNDINGS/SREF PLUMES. WEAK SHORT WAVE RIDGING WILL EVOLVE ACROSS
AREA THURSDAY AS THE WEAK SURFACE FRONT LIFTS NORTH OF THE CWA.
MORE CONFIDENT WITH WARMER TEMPS THURSDAY AS THE FRONT REMAINS
VERY WEAK EARLY, THEN LIFTS NORTH OF THE AREA DURING THE DAY
ALLOWING FOR AMPLE INSOLATION. THIS SHOULD AID IN DESTABILIZING
THE ATMOSPHERE THOUGH SHEAR REMAINS THE LIMITING FACTOR.
THURSDAY NIGHT THROUGH FRIDAY NIGHT, SW FLOW EXPECTED TO PERSIST
AHEAD OF A STRONGER COLD FRONT APPROACHING LATE FRIDAY NIGHT.
THURSDAY NIGHT SHOULD STAY MOSTLY DRY. NO CHANGE TO PREVIOUS
THINKING FOR SHOWERS AND THUNDERSTORMS FRIDAY FOR INLAND SECTIONS
AS DECENT INSTABILITY AND UNIDIRECTIONAL WEST-SOUTHWEST FLOW IS
ENOUGH TO SUPPORT CHC POPS IN AFTERNOON INLAND OF SEA BREEZE. LOW
LEVEL THICKNESSES SUPPORT MID 80S FOR INLAND SECTIONS.
INCREASING CHANCES FOR SHOWERS/TSTMS AHEAD OF FRONT FRI NIGHT
INTO SAT WITH FRONT EXPECTED TO PUSH THROUGH AREA SAT MIDDAY.
DROPPED POPS SAT NIGHT WITH MODELS INDICATING FRONT S AND E OF
AREA. MILD OVERNIGHT TEMPS FRI AND WARM SATURDAY MORNING AHEAD OF
THE FRONT, HIGHS IN THE MID 70S INLAND TO 60S ALONG THE COAST.
SUNDAY INTO TUESDAY, MODELS INDICATE DRY CONDITIONS SUN AND SUN
NIGHT WITH HIGH PRESSURE EXTENDING OVER THE AREA FROM THE DELMARVA
REGION. HIGH MOVES OFFSHORE MON LEADING TO SOUTHEASTERLY FLOW
ACROSS EASTERN NC. SOME DIFFERENCES BEGIN TO APPEAR IN THE
EXTENDED GUIDANCE WITH THE GFS MUCH SLOWER WITH A FRONT
APPROACHING FROM THE WEST MONDAY NIGHT, WHILE THE ECMWF MOVES A
WEAK BOUNDARY INTO THE AREA BY EARLY TUESDAY MORNING. TEMPS FOR
THE WEEKEND INTO TUESDAY WILL BE NEAR CLIMATOLOGY WITH HIGHS IN
THE 70S AND LOWS IN THE 50S.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH WEDNESDAY NIGHT/...
AS OF 1245 AM WEDNESDAY...DIFFICULT FORECAST WITH CONVECTIVE
DEBRIS CLOUDS AND MIXING LIMITING RADIATIONAL COOLING AT
TIMES...AND PRECIPITATION APPROACHING THE TAF SITES FROM THE WEST.
THE PRECIPITATION WILL AFFECT ALL OF THE TAF SITES LATE TONIGHT
INTO WEDNESDAY MORNING ESPECIALLY KOAJ AND KEWN BUT SHOULD BE
MOSTLY LIGHT WITH BRIEF MVFR CONDITIONS. OUTSIDE OF THE
PRECIPITATION FORECAST SOUNDINGS INDICATED A SATURATED BOUNDARY
LAYER WHICH WILL LEAD TO FOG AND OR LOW STRATUS CLOUDS. NEW BERN
HAS DECOUPLED AS HAS RICHLANDS SO THESE AREAS HAVE THE BEST
POTENTIAL FOR IFR FOG OVERNIGHT AS THE GUIDANCE INDICATES THAT
KPGV AND KISO MAY REMAIN MIXED. HOWEVER THE HRRR AND NARRE
GUIDANCE IS INDICATING IFR CEILINGS ALL TAF SITES BY 09Z SO
EXPECTING POOR CONDITIONS OVERNIGHT EARLY WEDNESDAY FOR AT LEAST
SEVERAL HOURS AT ALL OF THE TAF SITES. CONDITIONS SHOULD IMPROVE
TO VFR LATE WEDNESDAY MORNING AND AFTERNOON OUTSIDE OF ANY
SCATTERED SHOWER/THUNDERSTORM ACTIVITY THAT DEVELOPS. GUIDANCE IS
AGAIN POINTING TO THE POTENTIAL FOR IFR CONDITIONS REDEVELOPING
AGAIN WEDNESDAY EVENING AS THE BL REMAINS SATURATED.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 430 PM TUESDAY...SOME LOWER CIGS COULD PERSIST THURS
MORNING WITH LOW LEVEL NE FLOW. VFR MAINLY EXPECTED THURS NIGHT
INTO FRIDAY...THEN HIGHER THREAT OF SUB-VFR CONDITIONS FRI NIGHT
INTO SAT WITH GOOD COVERAGE OF SHOWERS AND TSTMS EXPECTED AS
STRONGER FRONT MOVES INTO AREA. GUSTY SW WINDS 15-25 MPH LIKELY
FRIDAY AHEAD OF FRONT. HIGH PRESSURE WILL ALLOW AVIATION
CONDITIONS TO IMPROVE TO VFR SATURDAY EVENING THROUGH SUNDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1245 AM WEDNESDAY...NO CHANGES TO PREVIOUS THINKING.
OFFSHORE HIGH PRESSURE WILL CONTINUE TO EXTEND WEST INTO THE NC
WATERS THROUGH TONIGHT. S-SW FLOW 5 TO 15 KT WITH SEAS MAINLY 2-4
FT. SW WINDS 10-15 KT MOST OF THE DAY ON WED EXCEPT FOR THE NRN
WATERS WHERE A BACKDOOR FRONT MOVES INTO THE NRN COASTAL WATERS
LATE. WINDS SHIFT TO N ACROSS THE NRN WATERS AROUND 10 KT IN THE
AFTERNOON. SEAS WILL BE 2-4 FT ON WED.
LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 430 PM TUESDAY...WEAK BACKDOOR FRONT WILL SAG SOUTH INTO THE
EASTERN NC WATERS WED EVENING INTO WED NIGHT, WITH FRONT EXPECTED
TO RETURN NORTH THURS. WINDS GENERALLY 15 KT OR LESS WITH THIS
FRONT. STRONGEST WINDS EXPECTED FRI AND FRI NIGHT AHEAD OF
STRONGER COLD FRONT, SW 15-25 KT WITH SEAS BUILDING TO SMALL CRAFT
ADVISORY LEVELS FRI NIGHT THROUGH MIDDAY SATURDAY. NE SURGE 10-20 KT
EXPECTED LATE SAT THROUGH SUNDAY. ADJUSTED SEAS WITH LATEST NWPS.
HEIGHTS MAINLY 3-4 FT WED-THURS, BUILDING TO 4-6 FT FRI-SAT THEN
DIMINISHING 2-4 FT SUNDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JAC
NEAR TERM...JAC/JME/BTC
SHORT TERM...JAC
LONG TERM...DAG
AVIATION...JME/DAG
MARINE...JAC/JME/BTC/DAG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1158 PM CDT TUE APR 7 2015
.UPDATE...
ISSUED AT 1158 PM CDT TUE APR 7 2015
INCLUDED A BIT OF MIXED PRECIP IN THE SOUTHEASTERN COUNTIES AS
PRECIP WINDS DOWN. A FEW SPOTS HAVE REPORTED SOME SLEET. SHOULD
NOT LAST TOO MUCH LONGER.
UPDATE ISSUED AT 945 PM CDT TUE APR 7 2015
PRECIP CURRENTLY STRETCHING FROM LAKE OF THE WOODS DOWN IN A
NARROWING BAND TOWARDS FARGO. THE PRECIP SHOULD CONTINUE TO PUSH
EASTWARD AS A RAIN/SNOW MIX AND ADJUSTED GRIDS TO REFLECT THE
RADAR TRENDS AND RAP/HRRR WHICH SEEM TO HAVE A GOOD HANDLE ON THE
PRECIP. THE 21Z SREF HAS BACKED OFF ON THE VERY HIGH PROBABILITIES
OF LOW VISIBILITY IN THE NORTHWESTERN COUNTIES...BUT THE RAP AND
HRRR STILL HAVE SOME FOG FORMATION. A FEW SPOTS IN THE JAMES AND
SHEYENNE VALLEYS HAVE SEEN DROPS IN VISIBILITY SO WILL KEEP THE
PATCHY/AREAS OF FOG FORMATION FOR NOW BUT AT THIS POINT DO NOT
THINK WE WILL GET A LOT OF SUPER DENSE FOG.
UPDATE ISSUED AT 652 PM CDT TUE APR 7 2015
TWEAKED POPS FOR CURRENT RADAR TRENDS...THINK THAT THE PRECIP
SHOULD CONTINUE TO MOVE EASTWARD THROUGH THE RED RIVER VALLEY AND
WILL BE MOSTLY IN WESTERN MINNESOTA BY LATE EVENING. REPORTS HAVE
1 TO 2 INCHES MAINLY IN THE NORTHERN COUNTIES...SO WILL KEEP THE
1-3 INCH ACCUMULATIONS NORTH OF HIGHWAY 2 THAT WE HAVE GOING. SREF
PROBABILITIES AND HRRR VIS SHOW SOME FOG IN THE DEVILS LAKE BASIN
TOWARDS MORNING. BUMPED UP MENTION TO AREAS OF FOG AND WILL KEEP
AN EYE ON DENSITY FOR NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 300 PM CDT TUE APR 7 2015
CHALLENGES CENTER AROUND PRECIP AND PRECIP TYPE THROUGH THU...THEN
TEMPS. MODELS ARE IN PRETTY GOOD OVERALL AGREEMENT THROUGH
FRIDAY...LEADING TO SOME INCREASED CONFIDENCE IN THIS FORECAST.
FOR THE REST OF THIS AFTERNOON AND OVERNIGHT...THE BAND OF PRECIP
WILL SLOWLY SHIFT FROM WEST TO EAST. THERE IS STRONG OMEGA/WAA IN
THE MID LEVELS THAT SHOULD TARGET AREAS ALONG AND NORTH OF US
HIGHWAY 2 THROUGH 6Z. EXPECT MOST SNOW IN THE FAR NORTH WITH A MIX
OF RAIN/SNOW POSSIBLE FURTHER SOUTH AND PROBABLY JUST RAIN IN THE
SOUTH. THERE COULD BE AN INCH OR 2 OF SNOW IN THE NORTH THROUGH
THE OVERNIGHT...WITH SOME SLICK SPOTS IF SNOW RATES BECOME HIGH
ENOUGH AND AFTER DARK. TEMPS WON/T FALL TOO MUCH OVERNIGHT GIVEN
THE POTENTIAL OF LOW CLOUDS AND EVEN SOME PATCHY FOG LATE IN THE
WEST. FOR NOW WON/T MENTION FOG...BUT POTENTIAL WILL HAVE TO BE MONITORED.
FOR WED...IT SHOULD BE DRY FOR MOST OF THE DAY...WITH THE THREAT
FOR SOME LIGHT PRECIP MOVING INTO THE WEST AND SOUTH TOWARDS 00Z
THU. TEMPS SHOULD WARM A BIT FROM TODAY...AND HINGE LARGELY ON IF
THERE IS ANY SUNSHINE.
FOR WED NIGHT...THE COLUMN WILL SATURATE AS A LARGE STORM SYSTEM
MOVES INTO THE CENTRAL PLAINS. EXPECT SOME RAIN INITIALLY IN THE
SOUTH WITH PRECIP POSSIBLY MIXING WITH SOME SNOW FURTHER NORTH
OVERNIGHT. NOT EXPECTING HEAVY PRECIP RATES WITH THIS SYSTEM...SO
LITTLE IF ANY SNOW ACCUMS EXPECTED.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 300 PM CDT TUE APR 7 2015
FOR THURSDAY...ANY PRECIP SHOULD MOVE OUT OF THE SOUTHEAST FA BY
18Z. TEMPS WILL WARM A BIT FROM WED WITH SOME SUNSHINE EXPECTED.
ON FRIDAY...ANOTHER DRY DAY IS EXPECTED WITH TEMPS SIMILAR TO THU.
THERE WILL BE SOME COOL AIR ALOFT IN THE FAR NORTHEAST...AND CAN/T
RULE OUT A SPRINKLE...BUT FOR NOW WILL KEEP IT DRY.
FOR FRIDAY NIGHT THROUGH TUESDAY...WILL START OFF THE PERIOD WITH
RIDGING AT 500MB AND THUS MILD TEMPS FOR SAT/SUN. THE 12Z GFS SHOWS
A LITTLE PREFRONTAL PCPN ACROSS THE FA AS EARLY AS SATURDAY
AFTERNOON...WHILE THE OTHER MODELS ARE DRY. THINK PCPN CHANCES WILL
INCREASE AS A COLD FRONT MOVES THRU SUNDAY/SUN NIGHT. SHOULD STILL
BE WARM ENOUGH THAT THIS PCPN WILL FALL AS RAIN. MORE UNCERTAINTY
ENTERS THE FORECAST BY MON INTO TUE WITH THE 12Z GFS ESSENTIALLY
DRY. ECMWF SHOWS A LITTLE LIGHT PCPN BUT CONFIDENCE PRETTY LOW AT
THIS POINT. WILL KEEP THE LOW GUIDANCE PCPN CHANCES ON MONDAY BUT
THINK THAT MAY BE OVERDONE. SHOULD BE A LITTLE COOLER MON/TUE BEHIND
THE COLD FRONT BUT TEMPS STILL LOOK TO BE WARMER THAN NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1158 PM CDT TUE APR 7 2015
KDVL HAS ALREADY DROPPED BELOW IFR...EVERYONE ELSE IS CURRENTLY
MVFR. CIGS SHOULD START TO DROP DOWN A BIT MORE IN THE VALLEY AND
SOME VIS AROUND 2-5SM IS POSSIBLE. HAVE KDVL GOING DOWN TO 1SM OR
SO EARLY THIS MORNING. SHOULD IMPROVE TO MVFR BY MID MORNING AND
THEN VFR BY LATE IN THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...DK
LONG TERM...GODON/DK
AVIATION...JR
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
602 AM EDT WED APR 8 2015
.SYNOPSIS...
A QUASI-STATIONARY FRONT WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PENNSYLVANIA TODAY THROUGH THURSDAY. A COLD FRONT
WILL MOVE THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE SHOWER ACTIVITY FROM OVERNIGHT HAS DECREASED AS EXPECTED.
SHOWERS AND A FEW THUNDERSTORMS ARE FORMING TO THE WEST AND THIS
SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED TO INCREASE LATE THIS
MORNING AND INTO THE AFTERNOON. PATCHY DENSE FOG HAS FORMED IN
MANY LOCATIONS THIS MORNING...INCLUDING REPORTS IN NW PA. I WILL
EXPAND THE MENTION OF PATCHY DENSE FOG TO ALMOST ALL AREAS FOR THE
NEXT FEW HOURS. MINOR ADJUSTMENTS TO TEMPERATURES AND PRECIPITATION
TO REFLECT THE CURRENT TRENDS.
PREVIOUS DISCUSSION...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PA TODAY. LITTLE MOVEMENT IS EXPECTED WITH THE FRONT
WHICH IS TYPICAL FOR THIS TIME OF YEAR AS THESE TYPE OF STATIONARY
FRONTS SET UP ON THE SOUTH SHORE OF LAKE ERIE. SHOWERS ARE EXPECTED
NEAR THE FRONTAL BOUNDARY TODAY BUT I DO NOT EXPECT WIDE SPREAD
AREAL COVERAGE. IT WILL BE TOUGH TO PREDICT THE TIMING. LOCALIZED
BOUNDARIES AND DAYTIME HEATING WILL MOST LIKELY TRIGGER THE SHOWERS.
THIS IS RE-ENFORCED BY THE HRRR MODEL AS SEVERAL RUNS INDICATED
SCATTERED/ISOLATED SHOWER PATTERN OVER THE REGION THROUGH THE DAY.
I WILL KEEP HIGH CHANCE TO LOW LIKELY RANGED POPS OVER THE AREA.
THUNDER IS POSSIBLE AND THE THREAT WILL INCREASE THIS AFTERNOON.
THE STORM PREDICTION CENTER HAS PLACED SOME OF THE NORTHWEST AND
NORTH CENTRAL OHIO IN A SLIGHT RISK CATEGORY FOR SEVERE
THUNDERSTORMS TODAY. BIG TEMPERATURE GRADIENT AGAIN NORTH TO SOUTH
ACROSS THE AREA. NORTHEAST FLOW NEAR THE LAKE WILL KEEP
TEMPERATURES MUCH COOLER
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER THE FORECAST AREA
WEDNESDAY NIGHT INTO THURSDAY. WITH THE LACK OF STRONG DYNAMICS
EARLY IN THE PERIOD...THE SHOWERS WILL ONCE AGAIN BE DIFFICULT TO TIME.
SHOWERS AND A FEW THUNDERSTORMS WILL REMAIN OVER THE AREA BUT IT
WILL BE FAIRLY UNORGANIZED. AS THE SHORT WAVE IN ADVANCE OF THE
COLD FRONT BEGINS TO MOVE TOWARDS THE AREA THURSDAY...THE STATIONARY
FRONT WILL MOVE NORTHWARD AS A WARM FRONT AND THE UPPER LEVEL
SUPPORT WILL BECOME MORE FOCUSED. A LARGE AREA OF Q-VECTOR
CONVERGENCE IS NOTED THURSDAY NIGHT WITH THE UPPER LEVEL SYSTEM.
THE SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH MORE NUMEROUS
AND ORGANIZED ON THURSDAY NIGHT AND SEVERE WEATHER THREAT IS STILL A
QUESTION. THE TIMING IS NOT OPTIMAL AS THE BEST LIFT WILL OCCUR
DURING THE OVERNIGHT HOURS. WE WILL STILL CONTINUE TO MONITOR THE
THREAT. AT THIS TIME MOST OF THE FORECAST AREA HAS A MARGINAL RISK
FOR SEVERE THUNDERSTORMS THURSDAY NIGHT.
THE COLD FRONT WILL SWEEP ACROSS THE REGION ON FRIDAY. A FEW
SHOWERS AND A POSSIBLE THUNDERSTORM MAY LINGER OVER THE EASTERN
SECTIONS OF THE AREA FRIDAY MORNING BUT SHOWER ACTIVITY SHOULD
RAPIDLY DECREASE IN THE AFTERNOON. DRY AIR AND COLD ADVECTION WILL
OCCUR FRIDAY NIGHT. 850MB TEMPS AS LOW AS -8C COULD MOVE OVER THE
LAKE FRIDAY NIGHT INTO EARLY SATURDAY. A FEW WET SNOW FLAKES ARE
NOT OUT OF THE QUESTION FOR NE OH AND NW PA BUT I WILL LEAVE THE
MENTION OF SNOW OUT OF THE FORECAST AT THIS TIME. THE AIR IS VERY
DRY BEHIND THE FRONT AND IT MAY BE DIFFICULT TO GET ANY TYPE OF
PRECIPITATION WITHOUT ASSISTANCE FROM THE LAKE. HIGH PRESSURE WILL
BUILD OVER THE REGION LATE SATURDAY THROUGH SATURDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE OVER THE AREA SHOULD PROVIDE DRY CONDITIONS ON SUN
AND ALLOW TEMPS TO MODERATE BACK A FEW DEGREES ABOVE NORMAL. THE DRY
CONDITIONS WILL QUICKLY CHANGE GOING INTO SUN NIGHT AS RETURN FLOW
MOISTURE ARRIVES ALONG WITH A WEAK COLD FRONT FROM THE WEST. WILL
GENERALLY LEAVE SUN NIGHT FORECAST AS IS BUT ALLOW FOR A MORE
UNIFORM PRECIP THREAT ON MON. MODELS TRYING TO SHOW A REPEAT SETUP
OF THE CURRENT PATTERN WITH A FRONT STALLED NEAR THE AREA STARTING
BY TUE AND LASTING ALL WEEK SO WILL INCREASE POPS A LITTLE MORE.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
FRONT IN CENTRAL OH WILL DRIFT SLOWLY NORTH TO BE NEAR LAKE ERIE BY
MIDNIGHT. LITTLE WILL CHANGE INTO DAYLIGHT SO IFR SHOULD PREVAIL
WITH SCT SHRA. GUIDANCE INDICATES IMPROVEMENT TO MVFR/LOW VFR LATE
MORNING INTO MIDDAY. BETTER THREAT FOR TSRA THIS AFTERNOON AND EARLY
TONIGHT AS AIRMASS BECOMES MORE UNSTABLE...BUT WHERE AND WHEN TSRA
MAY OCCUR IS ANYBODY`S GUESS SO FOR NOW WILL KEEP OUT OF TAFS OTHER
THAN MENTION WITH VCTS. CONDITIONS SHOULD START TO LOWER AGAIN BY
LATE EVENING AS LOW LEVELS COOL A FEW DEGREES.
.OUTLOOK...NON VFR AT TIMES INTO FRIDAY...POSSIBLY CONTINUING IN NW
PA EARLY SATURDAY.
&&
.MARINE...
WILL LEAVE SCA FOR WEST PART OF THE LAKE GOING UNTIL 3 PM BUT COULD
BE TAKEN DOWN SOONER IF FRONT LIFTS INTO NEARSHORE WATERS A LITTLE
BEFORE THEN AND TURNS WINDS MORE SOUTH AT A DIMINISHED SPEED. MODELS
INDICATE THE FRONT MAY SAG BACK SOUTH OF THE LAKE TOWARD
EVENING...POSSIBLY DUE TO LAKE BREEZE ENHANCEMENT BUT THEN SHOULD
START TO LIFT BACK INTO THE LAKE LATER IN THE NIGHT AND CONTINUE OFF
TO THE NORTH ON THU. THE WARM AIR FLOWING OVER THE COLD LAKE SHOULD
PROVIDE A STABILIZING EFFECT SO WILL CONTINUE TO KEEP WINDS UNDER 20
KTS UNTIL THU NIGHT WHEN LOW LEVEL FLOW INCREASES MORE AND STARTS TO
TURN SW. THIS WILL PROVIDE MORE FAVORABLE CONDITIONS FOR WINDS TO
INCREASE TO AT LEAST 15 TO 25 KNOTS.
THE PASSAGE OF THE COLD FRONT LATE THU NIGHT AND FRI MORNING WILL
TURN THE WINDS TO THE WEST AND AS COLDER AIR MOVES IN CAN SEE WINDS
AROUND 30 KNOTS SO WILL INCREASE THE FORECAST. HIGH PRESSURE SLOWLY
PUSHES INTO OH TO GRADUALLY DIMINISH THE WINDS FRI NIGHT THRU SAT SO
THE SCA WILL END. NOT SURE IF THE ICE IS BROKEN UP ENOUGH OR NOT BUT
THIS MAY BE THE EVENT WHERE THE ICE TYPICALLY GETS PUSHED INTO THE
EAST END OF THE LAKE WITH THE STRONGER SW TO W WINDS.
THE HIGH WILL SHIFT OFF THE MID ATLANTIC COAST BY SUN NIGHT TO ALLOW
LIGHT WINDS TO TURN SE AND START TO INCREASE SOME.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
LEZ142>146.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET
SHORT TERM...GARNET
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
300 AM EDT WED APR 8 2015
.SYNOPSIS...
A QUASI-STATIONARY FRONT WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PENNSYLVANIA TODAY THROUGH THURSDAY. A COLD FRONT
WILL MOVE THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PA TODAY. LITTLE MOVEMENT IS EXPECTED WITH THE FRONT
WHICH IS TYPICAL FOR THIS TIME OF YEAR AS THESE TYPE OF STATIONARY
FRONTS SET UP ON THE SOUTH SHORE OF LAKE ERIE. SHOWERS ARE EXPECTED
NEAR THE FRONTAL BOUNDARY TODAY BUT I DO NOT EXPECT WIDE SPREAD
AREAL COVERAGE. IT WILL BE TOUGH TO PREDICT THE TIMING. LOCALIZED
BOUNDARIES AND DAYTIME HEATING WILL MOST LIKELY TRIGGER THE SHOWERS.
THIS IS RE-ENFORCED BY THE HRRR MODEL AS SEVERAL RUNS INDICATED
SCATTERED/ISOLATED SHOWER PATTERN OVER THE REGION THROUGH THE DAY.
I WILL KEEP HIGH CHANCE TO LOW LIKELY RANGED POPS OVER THE AREA.
THUNDER IS POSSIBLE AND THE THREAT WILL INCREASE THIS AFTERNOON.
THE STORM PREDICTION CENTER HAS PLACED SOME OF THE NORTHWEST AND
NORTH CENTRAL OHIO IN A SLIGHT RISK CATEGORY FOR SEVERE
THUNDERSTORMS TODAY. BIG TEMPERATURE GRADIENT AGAIN NORTH TO SOUTH
ACROSS THE AREA. NORTHEAST FLOW NEAR THE LAKE WILL KEEP
TEMPERATURES MUCH COOLER
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER THE FORECAST AREA
WEDNESDAY NIGHT INTO THURSDAY. WITH THE LACK OF STRONG DYNAMICS
EARLY IN THE PERIOD...THE SHOWERS WILL ONCE AGAIN BE DIFFICULT TO TIME.
SHOWERS AND A FEW THUNDERSTORMS WILL REMAIN OVER THE AREA BUT IT
WILL BE FAIRLY UNORGANIZED. AS THE SHORT WAVE IN ADVANCE OF THE
COLD FRONT BEGINS TO MOVE TOWARDS THE AREA THURSDAY...THE STATIONARY
FRONT WILL MOVE NORTHWARD AS A WARM FRONT AND THE UPPER LEVEL
SUPPORT WILL BECOME MORE FOCUSED. A LARGE AREA OF Q-VECTOR
CONVERGENCE IS NOTED THURSDAY NIGHT WITH THE UPPER LEVEL SYSTEM.
THE SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH MORE NUMEROUS
AND ORGANIZED ON THURSDAY NIGHT AND SEVERE WEATHER THREAT IS STILL A
QUESTION. THE TIMING IS NOT OPTIMAL AS THE BEST LIFT WILL OCCUR
DURING THE OVERNIGHT HOURS. WE WILL STILL CONTINUE TO MONITOR THE
THREAT. AT THIS TIME MOST OF THE FORECAST AREA HAS A MARGINAL RISK
FOR SEVERE THUNDERSTORMS THURSDAY NIGHT.
THE COLD FRONT WILL SWEEP ACROSS THE REGION ON FRIDAY. A FEW
SHOWERS AND A POSSIBLE THUNDERSTORM MAY LINGER OVER THE EASTERN
SECTIONS OF THE AREA FRIDAY MORNING BUT SHOWER ACTIVITY SHOULD
RAPIDLY DECREASE IN THE AFTERNOON. DRY AIR AND COLD ADVECTION WILL
OCCUR FRIDAY NIGHT. 850MB TEMPS AS LOW AS -8C COULD MOVE OVER THE
LAKE FRIDAY NIGHT INTO EARLY SATURDAY. A FEW WET SNOW FLAKES ARE
NOT OUT OF THE QUESTION FOR NE OH AND NW PA BUT I WILL LEAVE THE
MENTION OF SNOW OUT OF THE FORECAST AT THIS TIME. THE AIR IS VERY
DRY BEHIND THE FRONT AND IT MAY BE DIFFICULT TO GET ANY TYPE OF
PRECIPITATION WITHOUT ASSISTANCE FROM THE LAKE. HIGH PRESSURE WILL
BUILD OVER THE REGION LATE SATURDAY THROUGH SATURDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE OVER THE AREA SHOULD PROVIDE DRY CONDITIONS ON SUN
AND ALLOW TEMPS TO MODERATE BACK A FEW DEGREES ABOVE NORMAL. THE DRY
CONDITIONS WILL QUICKLY CHANGE GOING INTO SUN NIGHT AS RETURN FLOW
MOISTURE ARRIVES ALONG WITH A WEAK COLD FRONT FROM THE WEST. WILL
GENERALLY LEAVE SUN NIGHT FORECAST AS IS BUT ALLOW FOR A MORE
UNIFORM PRECIP THREAT ON MON. MODELS TRYING TO SHOW A REPEAT SETUP
OF THE CURRENT PATTERN WITH A FRONT STALLED NEAR THE AREA STARTING
BY TUE AND LASTING ALL WEEK SO WILL INCREASE POPS A LITTLE MORE.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
FRONT IN CENTRAL OH WILL DRIFT SLOWLY NORTH TO BE NEAR LAKE ERIE BY
MIDNIGHT. LITTLE WILL CHANGE INTO DAYLIGHT SO IFR SHOULD PREVAIL
WITH SCT SHRA. GUIDANCE INDICATES IMPROVEMENT TO MVFR/LOW VFR LATE
MORNING INTO MIDDAY. BETTER THREAT FOR TSRA THIS AFTERNOON AND EARLY
TONIGHT AS AIRMASS BECOMES MORE UNSTABLE...BUT WHERE AND WHEN TSRA
MAY OCCUR IS ANYBODY`S GUESS SO FOR NOW WILL KEEP OUT OF TAFS OTHER
THAN MENTION WITH VCTS. CONDITIONS SHOULD START TO LOWER AGAIN BY
LATE EVENING AS LOW LEVELS COOL A FEW DEGREES.
.OUTLOOK...NON VFR AT TIMES INTO FRIDAY...POSSIBLY CONTINUING IN NW
PA EARLY SATURDAY.
&&
.MARINE...
WILL LEAVE SCA FOR WEST PART OF THE LAKE GOING UNTIL 3 PM BUT COULD
BE TAKEN DOWN SOONER IF FRONT LIFTS INTO NEARSHORE WATERS A LITTLE
BEFORE THEN AND TURNS WINDS MORE SOUTH AT A DIMINISHED SPEED. MODELS
INDICATE THE FRONT MAY SAG BACK SOUTH OF THE LAKE TOWARD
EVENING...POSSIBLY DUE TO LAKE BREEZE ENHANCEMENT BUT THEN SHOULD
START TO LIFT BACK INTO THE LAKE LATER IN THE NIGHT AND CONTINUE OFF
TO THE NORTH ON THU. THE WARM AIR FLOWING OVER THE COLD LAKE SHOULD
PROVIDE A STABILIZING EFFECT SO WILL CONTINUE TO KEEP WINDS UNDER 20
KTS UNTIL THU NIGHT WHEN LOW LEVEL FLOW INCREASES MORE AND STARTS TO
TURN SW. THIS WILL PROVIDE MORE FAVORABLE CONDITIONS FOR WINDS TO
INCREASE TO AT LEAST 15 TO 25 KNOTS.
THE PASSAGE OF THE COLD FRONT LATE THU NIGHT AND FRI MORNING WILL
TURN THE WINDS TO THE WEST AND AS COLDER AIR MOVES IN CAN SEE WINDS
AROUND 30 KNOTS SO WILL INCREASE THE FORECAST. HIGH PRESSURE SLOWLY
PUSHES INTO OH TO GRADUALLY DIMINISH THE WINDS FRI NIGHT THRU SAT SO
THE SCA WILL END. NOT SURE IF THE ICE IS BROKEN UP ENOUGH OR NOT BUT
THIS MAY BE THE EVENT WHERE THE ICE TYPICALLY GETS PUSHED INTO THE
EAST END OF THE LAKE WITH THE STRONGER SW TO W WINDS.
THE HIGH WILL SHIFT OFF THE MID ATLANTIC COAST BY SUN NIGHT TO ALLOW
LIGHT WINDS TO TURN SE AND START TO INCREASE SOME.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
LEZ142>146.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET
SHORT TERM...GARNET
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS NORMAN OK
424 AM CDT WED APR 8 2015
.DISCUSSION...
AN APPROACHING UPPER-LEVEL WAVE MAY GENERATE A FEW
SHOWERS/THUNDERSTORMS THIS MORNING OR EARLY AFTERNOON OVER NORTH
TEXAS AND OKLAHOMA. THESE SHOWERS/STORMS WOULD BE ELEVATED...AND
WOULD POSE LITTLE OR NO RISK OF PRODUCING SEVERE WEATHER.
THE RISK OF SEVERE WEATHER LATER THIS AFTERNOON AND THIS EVENING
CONTINUES TO BE PROBLEMATIC...AS A RATHER STRONG CAPPING INVERSION
WILL REDUCE THE ABILITY OF STORMS TO DEVELOP IN AN OTHERWISE
FAVORABLE ENVIRONMENT FOR SEVERE WEATHER. WE CONTINUE WITH
RELATIVELY LOW PROBABILITIES OF RAIN...BUT IT IS STILL THE CASE
THAT ANY STORM OR STORMS THAT DO FORM WILL HAVE PLENTY OF
INSTABILITY AND SHEAR TO WORK WITH. THE PRESENCE OF A DRYLINE AND
STATIONARY FRONT WILL LIKELY OVERCOME THE CAP...AT LEAST NEAR THE
KANSAS BORDER...THIS AFTERNOON. THAT CONVECTION WILL LIKELY
GENERATE NEW CONVECTION AS OUTFLOW BOUNDARIES PROVIDE SUFFICIENT
LOW-LEVEL CONVERGENCE TO OVERCOME THE WEAKER PARTS OF THE CAP.
STORMS THAT DEVELOP WILL LIKELY PERSIST INTO THE NIGHT.
STORMS WILL CONTINUE OFF AND ON INTO TOMORROW AFTERNOON...AND AN
APPARENTLY SLOWER MOVEMENT OF THE COLD FRONT WILL KEEP RAIN
CHANCES IN OUR SOUTHEAST COUNTIES THROUGH EARLY FRIDAY. IN
ADDITION TO THE SLOWNESS...IT APPEARS THAT THE FRONT WILL NOT GO
VERY FAR SOUTH...AND RETURN MOISTURE WILL BRING RAIN CHANCES BACK
INTO OUR SOUTHERN COUNTIES FRIDAY EVENING...ELIMINATING THE ONLY
DAY THAT HAD BEEN FORECAST TO BE COMPLETELY RAIN-FREE BETWEEN NOW
AND THE EARLY PART OF NEXT WEEK.
SHOWERS AND STORMS WILL PROBABLY BECOME FAIRLY NUMEROUS OVER THE
WEEKEND...THEN DIMINISH SLOWLY IN PROBABILITY INTO EARLY NEXT
WEEK.
ALSO PROBLEMATIC TODAY IS THE WILDFIRE POTENTIAL FOR THIS
AFTERNOON AND THIS EVENING. ALL MODELS SHOW THE DRYLINE FARTHER
WEST THAN BEFORE...AND NONE OF THEM SUPPORT A RED FLAG WARNING
OUTSIDE THE NEW WARNING AREA...GENERALLY WEST OF A LINE FROM
WOODWARD TO SAYRE. THE HRRR DOES SHOW THE DRYLINE FARTHER EAST
THAN THIS...BUT DOES NOT HAVE SUFFICIENT WIND SPEEDS OUTSIDE THIS
AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 82 63 78 49 / 20 30 10 10
HOBART OK 87 61 78 46 / 20 20 10 10
WICHITA FALLS TX 85 66 84 51 / 20 30 10 10
GAGE OK 92 53 71 39 / 10 10 0 0
PONCA CITY OK 81 60 74 44 / 40 30 10 10
DURANT OK 80 66 77 53 / 20 30 30 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS
EVENING FOR OKZ004-009-010-014-021.
TX...NONE.
&&
$$
09/23
AREA FORECAST DISCUSSION
NWS TULSA OK
1149 PM CDT TUE APR 7 2015
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
RATHER STRONG SOUTHERLY WINDS WILL PREVAIL THROUGH THE FORECAST
PERIOD. MVFR CEILINGS WILL DEVELOP AROUND SUNRISE AT ALL SITES
WITH SOME IMPROVEMENT EXPECTED BY AFTERNOON. WIDELY SCATTERED
THUNDERSTORMS WILL BE POSSIBLE WEDNESDAY AFTERNOON AND EVENING BUT
THE EXPECTED COVERAGE IS TOO LOW TO INCLUDE IN THE TAFS AT THIS
TIME.
&&
.PREV DISCUSSION... /ISSUED 935 PM CDT TUE APR 7 2015/
..UPDATE...
DISCUSSION...
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 2 AM FOR THE
NORTHERN TIER OF COUNTIES IN NORTHEAST OKLAHOMA. RAISED POPS IN
THAT AREA EARLIER THIS EVENING BUT SO FAR HAVE HAD NO CONVECTIVE
DEVELOPMENT SOUTH OF THE KANSAS BORDER. STORMS WILL REMAIN
POSSIBLE OVERNIGHT IN THIS AREA. NO OTHER SIGNIFICANT CHANGES TO
THE AFTERNOON FORECAST HAVE BEEN MADE THIS EVENING.
PREV DISCUSSION... /ISSUED 608 PM CDT TUE APR 7 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE 0Z TAFS... VFR CONDITIONS WILL PREVAIL INTO THIS EVENING
AT ALL TAF SITES WITH FAIRLY STRONG SOUTHERLY WINDS CONTINUING. MVFR
CEILINGS ARE EXPECTED TO DEVELOP AREAWIDE BEFORE MIDNIGHT.
THUNDERSTORMS MAY AFFECT NORTHEAST OKLAHOMA SITES THIS EVENING BUT
CHANCES ARE LOW. MORE WIDESPREAD... POSSIBLE STRONG THUNDERSTORMS
WILL AFFECT ALL SITES BEGINNING WEDNESDAY AFTERNOON.
PREV DISCUSSION... /ISSUED 322 PM CDT TUE APR 7 2015/
DISCUSSION...
A WEAK FRONTAL BOUNDARY EXTENDS FROM WEST OF KANSAS CITY INTO NW
OKLAHOMA THIS AFTERNOON WITH A VERY UNSTABLE BUT STRONGLY CAPPED
AIRMASS RESIDING OVER EASTERN OK AND NORTHWEST AR. TEMPS ALONG AND
SE OF THE FRONT HAVE WARMED INTO THE MID 80S TO NEAR 90...AND ALSO
A SUBTLE OUTFLOW BOUNDARY FROM EARLIER STORMS PUSHING THROUGH SW
MISSOURI AT THIS TIME. NO SIGNIFICANT UPPER AIR FORCING AT THIS
POINT...BUT ISOLATED STORMS STILL MAY DEVELOP NEAR THE SFC FRONT
AND OUTFLOW BOUNDARY LATER THIS AFTERNOON OR EARLY THIS EVENING
AS HRRR AND TO A LESSER EXTENT OUR LOCALLY RUN 5KM WRF CONTINUE TO
INDICATE. GIVEN THE AMOUNT OF AVAILABLE CAPE AND AT LEAST MODERATE
SHEAR ANY STORMS COULD BECOME SEVERE SHOULD UPDRAFTS BE
SUSTAINED... LARGE HAIL AND WINDS THE MAIN THREATS. CAP WILL
REMAIN WITH US FOR THE MOST PART THROUGH TONIGHT WITH ONLY A
LIMITED CHANCE OF STORMS NEAR KANSAS AND MISSOURI BORDERS.
UNSTABLE AND CAPPED ENVIRONMENT REMAINS WITH US WEDNESDAY...
HOWEVER WITH UPPER LOW CURRENTLY OFF THE CALIFORNIA COAST MOVING
INTO THE CENTRAL ROCKIES DURING THE DAY...MID LEVEL HEIGHT FALLS
AND A POTENTIAL LEAD SHORT WAVE/ JET STREAK SHOULD HELP ERODE THE
CAP ENOUGH FOR SOME STORMS TO DEVELOP ALONG THE DRY LINE FROM
CENTRAL KS INTO NORTHERN OK. MOST LIKELY TIME WOULD BE 21-00Z
HOWEVER EARLIER RUNS OF THE NAM HAVE SHOWN SOME EARLIER
DEVELOPMENT THAN THAT. WIND PROFILES SUGGEST THAT ONCE A STORM
DEVELOPS IT WILL QUICKLY BECOME SUPERCELLULAR AND POSE A THREAT
FOR VERY LARGE GAIL AND DAMAGING WINDS...AND SOME DEGREE OF
TORNADO POTENTIAL. OVERALL STORM COVERAGE IS EXPECTED TO REMAIN
FAIRLY LIMITED THROUGH WED NIGHT DUE TO PERSISTENT CAP ISSUES.
MAIN UPPER SYSTEM CONTINUES TO PROGRESS EAST THURSDAY WITH A COLD
FRONT OVERTAKING THE DRY LINE AND LIKELY PUSHING THROUGH PARTS OF
NE OKLAHOMA BY EARLY AFTERNOON. CONTINUED MOIST AND VERY UNSTABLE
AHEAD OF THE FRONT WITH MORE WIDESPREAD THUNDERSTORMS LIKELY THU
AFTERNOON AND EVENING MAINLY OVER SOUTHEAST OK AND NORTHWEST AR.
SHEAR PROFILES SUGGEST A MORE LINEAR STORM MODE AT THIS TIME.
STORMS WILL END THU EVENING WITH A COOLER AND STABLE AIRMASS
SETTLING OVER THE AREA FRIDAY.
ANOTHER UPPER LEVEL SYSTEM WILL MOVE IN FROM THE WEST BY THIS
WEEKEND AND WITH THE PRESENCE OF A SFC BOUNDARY IN THE AREA...
THUNDERSTORM CHANCES WILL RETURN BY SATURDAY AND CONTINUE INTO
EARLY NEXT WEEK. GENERAL CONSENSUS IS THIS UPPER LOW WILL
ULTIMATELY TACK A MUCH MORE SOUTHERLY TRACK...ANY SEVERE WEATHER
THREATS DURING THIS TIME REMAIN EXTREMELY UNCERTAIN.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...05
AREA FORECAST DISCUSSION
NWS MEDFORD OR
1013 PM PDT TUE APR 7 2015
.UPDATE...UPDATED POPS TO TAPER OFF WEST SIDE POPS TO SCATTERED
SHOWERS AFTER MIDNIGHT AS THE UPPER LOW PULLS FARTHER TO THE
EAST. /FB
&&
.PREV DISCUSSION... /ISSUED 858 PM PDT TUE APR 7 2015/
DISCUSSION...THE CLOSED LOW PRESSURE HAS MOVED INTO NW
CALIFORNIA. THIS LOW WILL CONTINUE TO MOVE TO THE E-SE AND THE
CENTER IS EXPECTED TO BE IN NORTHERN NEVADA BY LATE TONIGHT.
SATELLITE IMAGERY SHOWS CONTINUED UPSLOPE PRECIPITATION INTO THE
WARNER MOUNTAINS AS WELL AS THE EAST SLOPES OF THE CASCADES. SHORT
TERM HIGH RESOLUTION MODELS CONTINUE TO PAINT SNOW SHOWERS ACROSS
THE WARNERS AS WELL AS THE MOUNTAINS OF EASTERN KLAMATH COUNTY,
WHILE ROADCAMS CONTINUE TO SHOW SNOW SHOWERS OVER THE CASCADES
PASSES. WILL KEEP THE CURRENT SUITE OF WINTER WEATHER ADVISORIES
GOING THROUGH THE NIGHT.
NEW MODEL RUNS SHOW NO BIG DEPARTURE FROM THE PREVIOUS FORECAST SO
NO UPDATES WILL ISSUED THIS EVENING. /FB
AVIATION...FOR THE 08/00Z TAF CYCLE...THIS EVENING THROUGH EARLY
WEDNESDAY MORNING...EXPECT MVFR CIGS/VISIBILITY FROM THE
CASCADES EASTWARD...WITH AREAS OF IFR IN LIGHT TO OCCASIONALLY
MODERATE SNOW SHOWERS. TERRAIN OBSCURATION WILL BE WIDESPREAD.
WEST OF THE CASCADES...EXPECT A MIX OF VFR/MVFR CIGS IN ISO/SCT
SHOWERS WITH MOUNTAINS OBSCURED. CONDITIONS WILL LIKELY IMPROVE TO
VFR FOR MOST AREAS MID TO LATE MORNING WEDNESDAY, THOUGH ISOLATED
SHOWERS WILL PERSIST. SPILDE
MARINE...UPDATED 400 PM PDT TUESDAY APR 07 2015...MAINLY LIGHT
WINDS AND LOW SEAS ARE EXPECTED TONIGHT THROUGH THURSDAY NIGHT AS
HIGH PRESSURE BUILDS INTO THE WATERS. A COLD FRONT WILL MOVE
THROUGH LATE FRIDAY OR FRIDAY NIGHT WITH SLIGHTLY HIGHER WINDS AND
SEAS. A LARGER WESTERLY SWELL WILL ARRIVE LATER SATURDAY NIGHT AND
PERSIST THROUGH MONDAY. SPILDE
PREV DISCUSSION... /ISSUED 500 PM PDT TUE APR 7 2015/
SHORT TERM...THE UPPER LOW CURRENTLY OFF THE COAST IN NORTHWEST
CAL IS MOVING SOUTH. WET SNOW CONTINUES IN SISKIYOU COUNTY, BUT
IT`S BECOMING SHOWERY AND ROADS ARE WET. THE MODELS ARE IN PRETTY
GOOD AGREEMENT SHOWING A DEFORMATION ZONE OF PRECIPITATION SETTING
UP EAST OF THE CASCADES LATER THIS EVENING AND LASTING INTO
WEDNESDAY MORNING, BUT DIFFER SLIGHTLY ON THE PLACEMENT OF THE
CORE OF HEAVIEST QPF. THE LATEST HRRR SHOWS THE DEFORMATION ZONE
WELL AND THE FORECAST FOR TONIGHT WILL LEAN TOWARDS THAT SOLUTION.
GIVEN THAT THIS WILL SET UP AT NIGHT, THERE WILL BE AN OPPORTUNITY
FOR SNOW TO ACCUMULATE ON ROADS DURING THE OVERNIGHT HOURS FOR
MOST AREAS EAST OF THE CASCADES. THE CASCADES WILL ALSO GET
ACCUMULATING SNOW TONIGHT, THUS HAVE EXTENDED THE END TIME OF THE
WINTER WEATHER ADVISORY UNTIL WEDNESDAY MORNING. DETAILS CAN BE
FOUND AT WSWMFR. GIVEN THE ABOVE MENTIONED SCENARIO, HAVE
INCREASED POPS...QPF AND SNOW AMOUNTS SIGNIFICANTLY, BUT IT STILL
MAY NOT BE ENOUGH. LATER SHIFTS MAY NEED TO TAKE ANOTHER LOOK AT
THIS AND ADJUST AMOUNTS HIGHER IF LATER MODEL RUNS CONTINUE TO
SHOW THE HIGHER QPF AMOUNTS.
WEDNESDAY WILL BE A TRANSITION DAY WITH THE DEFORMATION ZONE
WEAKENING IN THE MORNING. RAIN AND MOUNTAIN SNOW SHOWERS WILL
CONTINUE IN THE AFTERNOON, BUT SNOW LEVELS WILL COME UP TO AROUND
5000 FEET IN THE AFTERNOON, SO NOT EXPECTING MUCH IF ANY
ACCUMULATIONS FROM ABOUT MID MORNING WEDNESDAY ON DUE TO WARMING
ROAD TEMPERATURES AND SPOTTY PRECIPITATION.
DRY AND MILDER WEATHER FINALLY RETURNS THURSDAY AND CONTINUES INTO
THURSDAY NIGHT WITH SHORTWAVE RIDGING BUILDING INTO THE AREA.
MOST OF FRIDAY WILL BE DRY, THEN THE NEXT FRONT WILL REACH THE
COAST TOWARDS FRIDAY EVENING. THE GFS AND NAM ARE SLOWER WITH THE
ARRIVAL OF THE FRONT WHILE THE EC IS FASTER. FOR NOW WENT WITH A
BLEND BETWEEN THE TWO, BUT THE UPPER FLOW IS WEST OT NORTHWEST
WHICH NORMALLY LEADS TO QUICKER ARRIVAL TIMES OF FRONTS.
-PETRUCELLI
LONG TERM...THE ACTIVE PATTERN CONTINUES IN THE LONG TERM WITH
ANOTHER FRONTAL BOUNDARY MOVING INTO THE AREA LATE FRIDAY NIGHT
INTO SATURDAY MORNING. THE MODELS ARE IN FAIRLY GOOD AGREEMENT
THROUGH THE LONG TERM. THE EC IS A BIT FASTER TO PUSH THE FRONT
INLAND ON SATURDAY COMPARED TO THE GFS BUT BOTH MODELS HAVE IT
PUSHED THROUGH THE AREA BY LATE SATURDAY NIGHT. ZONAL FLOW WILL
SET UP FOR SUNDAY AND THE GFS IS HINTING AT SOME UPSLOPE SHOWERS
CONTINUING ALONG THE CASCADES THROUGH SUNDAY AFTERNOON. THERE MAY
ALSO BE SOME LINGERING SHOWERS FOR THE NORTHERN PORTION OF THE
CWA...MAINLY FROM THE UMPQUA DIVIDE NORTH. OTHERWISE, SUNDAY LOOKS
TO BE THE DRIEST DAY, RELATIVELY, THROUGH THE EXTENDED TERM. BY
MONDAY MORNING, THE MODELS ARE SLIGHTLY DIFFERENT IN THE TIMING
AND STRENGTH OF THE NEXT SYSTEM TO MOVE THROUGH. THE GFS IS FASTER
AND DEEPER WITH THE NEXT TROUGH, MEANING COOLER TEMPERATURES AND
LOWER SNOW LEVELS COMPARED TO THE EC...WHICH IS SLOWER BY ABOUT 12
HOURS AND NOT AS DEEP WITH THE TROUGH. EITHER WAY, IT LOOKS LIKE
UNSETTLED WEATHER WILL CONTINUE THROUGH THE END OF THE EXTENDED
TERM. MND
AVIATION...FOR THE 08/00Z TAF CYCLE...THIS EVENING THROUGH EARLY
WEDNESDAY MORNING...EXPECT MVFR CIGS/VISIBILITY FROM THE
CASCADES EASTWARD...WITH AREAS OF IFR IN LIGHT TO OCCASIONALLY
MODERATE SNOW SHOWERS. TERRAIN OBSCURATION WILL BE WIDESPREAD.
WEST OF THE CASCADES...EXPECT A MIX OF VFR/MVFR CIGS IN ISO/SCT
SHOWERS WITH MOUNTAINS OBSCURED. CONDITIONS WILL LIKELY IMPROVE TO
VFR FOR MOST AREAS MID TO LATE MORNING WEDNESDAY, THOUGH ISOLATED
SHOWERS WILL PERSIST. SPILDE
MARINE...UPDATED 500 PM PDT TUESDAY APR 07 2015...MAINLY LIGHT
WINDS AND LOW SEAS ARE EXPECTED TONIGHT THROUGH THURSDAY NIGHT AS
HIGH PRESSURE BUILDS INTO THE WATERS. A COLD FRONT WILL MOVE
THROUGH LATE FRIDAY OR FRIDAY NIGHT WITH SLIGHTLY HIGHER WINDS AND
SEAS. A LARGER WESTERLY SWELL WILL ARRIVE LATER SATURDAY NIGHT AND
PERSIST THROUGH MONDAY. SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 9 AM PDT WEDNESDAY FOR
ORZ029>031-624-625.
WINTER WEATHER ADVISORY UNTIL 9 AM PDT WEDNESDAY FOR
ORZ027-028-617-621-623.
CA...WINTER WEATHER ADVISORY UNTIL 9 AM PDT WEDNESDAY FOR CAZ085-285.
PACIFIC COASTAL WATERS...NONE.
$$
FJB/CC/FJB
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
528 AM EDT WED APR 8 2015
.SYNOPSIS...
A NEARLY STATIONARY FRONT JUST SOUTH OF PENNSYLVANIA WILL COMBINE
WITH STRONG HIGH PRESSURE OVER QUEBEC CANADA...TO KEEP MOIST AND
COOL CONDITIONS OVER THE REGION THROUGH THURSDAY WITH PERIODS OF
RAIN AND DRIZZLE...AND A GENERALLY LIGHT EAST TO NORTHEAST WIND.
DEEPENING LOW PRESSURE MOVING NORTHEAST ACROSS THE UPPER GREAT
LAKES THURSDAY NIGHT WILL PUSH ITS TRAILING COLD FRONT ACROSS
PENNSYLVANIA DURING THE MIDDAY AND AFTERNOON HOURS FRIDAY. MUCH
COOLER CONDITIONS WILL FOLLOW FOR SATURDAY...WITH EVEN A FEW SNOW
SHOWERS POSSIBLE ACROSS THE NORTHWEST MOUNTAINS SATURDAY MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE EARLIER LULL IN THE RAIN SHOWERS IS COMING TO AN END AS A
COMPACT AND QUITE FLAT UPPER SHORT WAVE SLIDES EAST OF THE
PENN/OHIO BORDER.
WEAK LLVL RIDGING THROUGH THE SUSQ VALLEY AND SCENT MTNS WILL
CONTINUE THE RELATIVE MIN IN SHOWERS THERE FOR THE NEXT 1-2 HOURS.
05Z HRRR WAS BLENDED IN TO POPULATE NEAR TERM POPS/WEATHER AND QPF
GRIDS THROUGH THIS AFTERNOON. THIS DATA SHOWS A STEADY PROGRESSION
OF SHOWERS ACROSS CENTRAL PENN DURING THE MID TO LATER MORNING
HOURS...FOLLOWED BY A DISTINCT LULL IN THE PRECIP THIS AFTERNOON
WITH WIDESPREAD STRATUS REMAINING AND JUST A FEW ISOLATED SHOWERS
OR SOME PATCHY DRIZZLE POSSIBLE.
CONSIDERING THE TIGHT TEMP/DWPT SPREAD OF GENERALLY 1-2 DEG F
ACROSS THE CENTRAL AND WESTERN ZONES...TEMPS ARE RIGHT NEAR THEIR
MINS. A SLIGHTLY GREATER T/TD SPREAD ACROSS THE SUSQ VALLEY WILL
ALLOW FOR A 2-4 DEG F TEMP DROP BETWEEN 10-12Z AS THE INCREASING
COVERAGE OF SHOWERS SPREADS EWD INTO THAT AREA.
HIGH TEMPS THIS AFTERNOON WILL BE MUCH COOLER THAN
TUESDAY...RANGING FROM AROUND 40 DEG ACROSS THE HIGHER TERRAIN OF
THE WRN POCONOS AND ENDLESS MTNS NW OF KIPT...TO THE MID 50S ON
THE WRN SIDE OF THE ATLANTIC/GOMEX WATER SHED BOUNDARY /NEAR THE
RT 219 CORRIDOR/.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
CLOUDY...COOL AND DAMP CONDITIONS WILL CONTINUE TONIGHT AS HIGH
PRESSURE OVER QUEBEC CANADA RIDGES SWWD INTO THE STATE ACCOMPANIED
BY A LIGHT EAST TO NE BREEZE. AT THE SAME TIME...MEAN TEMPS IN
THE 900-850 MB LAYER WILL INCREASE BY ABOUT 2-3 DEG C /BETWEEN
00Z-12Z THU/. THIS SHOULD LEAD TO RIDGE SHROUDING FOG ACROSS MUCH
OF THE REGION WITH THE LOWEST VSBYS ON THE EAST-FACING UPPER
SLOPES.
ANOTHER FLAT SHORTWAVE /OR MCV FROM WEAKENING UPSTREAM TSRA/
APPEARS TO MOVE EAST FROM THE OHIO VALLEY AND TARGET MUCH OF THE
REGION OVERNIGHT TONIGHT. CAN/T RULE OUT A FEW TSRA ACROSS OUR
WESTERN ZONES LATE TODAY/THIS EVENING...NEAR THE EASTERN EDGE OF
WEAK-MDT LEVELS OF MLCAPE OF 500-1000 J/KG. ELSEWHERE...A FEW
SHOWERS WILL BE LIKELY WITH BASIN AVG RAINFALL AMOUNTS AROUND 0.10
OF AN INCH /PERHAPS A FEW TENTHS HIGHER THOUGH ACROSS THE LAURELS
- CLOSER TO THE WEAKENING TSRA/.
TEMPS TONIGHT COULD DIP OR STAY 3-5F COOLER THAN MOST GUIDANCE AS
VERY SHALLOW AND ANOMALOUSLY COOL NEAR SFC AIR WILL BE FUNNELED
SWWD FROM THE NEW ENGLAND STATES AND HUDSON VALLEY. APPROX 03Z
SREF GUIDANCE WAS USED FOR TONIGHT/S MINS...WHICH SUPPORT A LOW
PROBABILITY FOR -FZRA/-FZDZ ACROSS THE WRN POCONOS AND ENDLESS
MTNS REGION NE OF KIPT. LOWS TONIGHT RANGE FROM THE LOWER 30S
ACROSS THE ERN HIGH TERRAIN...TO THE MID AND UPPER 40S WEST OF RT
219 IN WRN PENN.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
WARMER AIR WILL WORK INTO THE AREA LATE THU INTO FRIDAY...AS LOW
LEVEL WIND FIELDS INCREASE. WARMEST TEMPERATURES MIGHT END UP
BEING ACROSS WARREN COUNTY.
DID NOT UP TEMPS MUCH FOR FRIDAY...MODELS MOVE COLD FRONT ACROSS
THE AREA RATHER FAST.
SOME CHANCE OF A STRONG THUNDERSTORM ACROSS THE WEST LATER FRIDAY.
THIS BASED ON TIMING AND THE THERMAL RIDGE OVER THE BEST MOISTURE.
HAVE TO WATCH FOR SEVERE...BUT DYNAMICS LIKELY TO LIFT NE AWAY
FROM THE AREA. ALSO TIMING NOT THE BEST.
WHILE WE WILL SEE SOME SHOWERS EACH DAY THIS WEEK...NOT SEEING ANY
LARGE AMTS. THUS NOT SEEING ANY WIDESPREAD HYDRO CONCERNS AT THIS
POINT. ENJOY THE MILDER TEMPERATURES.
RATHER STRONG SMALL UPPER LEVEL TROUGH FOR LATE FRIDAY INTO SAT.
TOOK OUT SHOWERS AFTER EARLY FRIDAY EVENING. MAIN THING WAS TO
LOWER TEMPS FOR FRIDAY NIGHT INTO SAT...GIVEN AIRMASS TO THE NORTH
AND COLD ADVECTION.
WEEKEND SIMILAR TO LAST WEEKEND. BREEZY AND COOL ON SAT. WARMER
ON SUNDAY.
DID PUT SOME SHOWERS IN THE FAR WEST LATE MONDAY AND ACROSS THE
AREA ON TUE. MODELS SHOW ANOTHER COLD FRONT MOVING IN.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
LOW CIGS AND FOG WILL SUPPORT REDUCED FLYING CONDS ACROSS THE
ENTIRE AIRSPACE OVER NIGHT..WIDESPREAD MVFR AND IFR OR LOWER
ACROSS HIGHER ELEVATIONS. CONDS CAUSED BY FRONTAL BOUNDARY VCNTY
STATE AND ABUNDANT LOW LEVEL MOISTURE FROM ONGOING SHOWERS AND
THOSE FROM EARLIER TODAY.
WINDS WILL REMAIN LIGHT INTO WED.
OUTLOOK...
WED...WIDESPREAD MVFR/IFR IN SHRA/PERIODS OF RA.
THU...REDUCTIONS LIKELY IN SCT SHRA.
FRI...REDUCTIONS LIKELY IN SHRA...ESPECIALLY DURING THE
AFT. CHC OF THUNDER AFT.
SAT-SUN...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...MARTIN
AVIATION...DEVOIR/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
201 AM EDT WED APR 8 2015
.SYNOPSIS...
A STATIONARY FRONTAL BOUNDARY WILL REMAIN DRAPED FROM NORTHERN
VIRGINIA TO CENTRAL OHIO TODAY...BEFORE MOVING NORTHEAST ACROSS
PENNSYLVANIA AS A WARM FRONT ON THURSDAY. HIGH PRESSURE OVER THE
CANADIAN MARITIMES WILL SUPPLY A NORTHEAST FLOW OF COOL...MOIST
AIR INTO THE REGION TODAY...HELPING TO CREATE AREAS OF RAIN AND
DRIZZLE. A DEEP STORM SYSTEM WILL TRACK NORTHEAST ACROSS THE GREAT
LAKES ON FRIDAY...DRAGGING A TRAILING COLD FRONT THROUGH
PENNSYLVANIA.
&&
.NEAR TERM /UNTIL 9 AM THIS MORNING/...
REGIONAL RADAR MOSAIC AND LATEST...04Z HRRR INDICATE THAT THE BEST
CHANCE FOR RAIN THROUGH THE MID MORNING HOURS WILL BE ACROSS THE
NRN MTNS AND LAUREL HIGHLANDS OF SWRN PENN...CLOSE TO THE
STATIONARY FRONT NEAR THE MASON-DIXON LINE...AND AN INVERTED
TROUGH NEAR THE SOUTH SHORE OF LAKE ERIE.
WEAK LLVL RIDGING THROUGH THE SUSQ VALLEY AND CENT MTNS WILL
CONTINUE THE RELATIVE MIN IN SHOWERS THERE.
CONSIDERING THE TIGHT TEMP/DWPT SPREAD OF GENERALLY 2 DEG F OR
LESS...TEMPS WILL ONLY FALL ANOTHER DEG OR SO BY DAYBREAK...WITH
MINS RANGING FROM THE U30S ACROSS THE NRN AND ERN MTNS...TO THE
UPPER 40S IN OUR SWRN ZONES.
&&
.SHORT TERM /9 AM THIS MORNING THROUGH 6 PM THURSDAY/...
COOL AND DANK CONDITIONS WILL BE THE NORM TODAY IN LLVL CAD
REGIME WITH PLENTY OF LLVL MOISTURE AND OVERRUNNING ZONAL FLOW
ALOFT PROMOTING LIGHT SHOWERS ESPECIALLY IN THE AFTERNOON. HIGHS
WILL RANGE THROUGH THE 40S FOR MOST...BUT AREAS ALONG THE
ALLEGHENY FRONT MAY NUDGE INTO THE WARM SECTOR WITH WESTERN WARREN
AND WESTERN SOMERSET COUNTIES REACHING INTO THE 50S /AND PERHAPS
NEAR 60 ACROSS SOUTHWEST SOMERSET COUNTY/.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
DID NOT CHANGE POPS OR WEATHER FOR TONIGHT...GIVEN SLIGHT CHANCE
FOR A LITTLE FREEZING DRIZZLE OR RAIN ACROSS THE NE. LOWS NEAR
HUDSON AND JAMES BAY AREA WERE ZERO TO 20 BELOW THIS MORNING. THAT
IS VERY COLD FOR EARLY APRIL.
DETAILS BELOW...
GIVEN THE FACT THAT WE/LL HAVE A 1040 MB SFC HIGH BECOMING PARKED
ACROSS SRN QUEBEC /WHERE CURRENT TEMPS ARE IN THE SINGLE DIGITS TO
TEENS/ AND 1000 MB AGEOSTROPHIC FLOW INCREASING FROM THE
NORTH-NORTHEAST /AND STAYING THERE FOR A 24-36 HOUR PERIOD/...WENT
SEVERAL DEG F BELOW MODEL TEMPS FOR WED MAXES AND WED NIGHT MINS.
EVEN MENTIONED A SLIGHT CHC FOR LIGHT FZRA ACROSS PARTS OF THE
NCENT MTNS AND WRN POCONOS LATE WED NIGHT AND EARLY THURSDAY.
THIS LLVL COLD AIR DAMMING LIKELY TO LINGER INTO THURSDAY AFT.
SOME NEW DETAIL BELOW...
WHILE TEMPS MAY NOT WARM UP TO A GREAT EXTENT THU...AND I LEFT
THEM CLOSE TO WHAT WE HAD...WILL CONTINUE TO MONITOR. VERY TIGHT
TEMPERATURE GRADIENT AT 850 MB LATE WED EVENING ACROSS CENTRAL
NY...MINUS 4 TO PLUS 10 IN ABOUT 80 TO 100 MILE BAND.
ANYWAY...WARMER AIR WILL WORK INTO THE AREA LATE THU INTO
FRIDAY...AS LOW LEVEL WIND FIELDS INCREASE. WARMEST TEMPERATURES
MIGHT END UP BEING ACROSS WARREN COUNTY.
DID NOT UP TEMPS MUCH FOR FRIDAY...MODELS MOVE COLD FRONT ACROSS
THE AREA RATHER FAST.
SOME CHANCE OF A STRONG THUNDERSTORM ACROSS THE WEST LATER FRIDAY.
THIS BASED ON TIMING AND THE THERMAL RIDGE OVER THE BEST MOISTURE.
HAVE TO WATCH FOR SEVERE...BUT DYNAMICS LIKELY TO LIFT NE AWAY
FROM THE AREA. ALSO TIMING NOT THE BEST.
WHILE WE WILL SEE SOME SHOWERS EACH DAY THIS WEEK...NOT SEEING ANY
LARGE AMTS. THUS NOT SEEING ANY WIDESPREAD HYDRO CONCERNS AT THIS
POINT. ENJOY THE MILDER TEMPERATURES.
RATHER STRONG SMALL UPPER LEVEL TROUGH FOR LATE FRIDAY INTO SAT.
TOOK OUT SHOWERS AFTER EARLY FRIDAY EVENING. MAIN THING WAS TO
LOWER TEMPS FOR FRIDAY NIGHT INTO SAT...GIVEN AIRMASS TO THE NORTH
AND COLD ADVECTION.
WEEKEND SIMILAR TO LAST WEEKEND. BREEZY AND COOL ON SAT. WARMER
ON SUNDAY.
DID PUT SOME SHOWERS IN THE FAR WEST LATE MONDAY AND ACROSS THE
AREA ON TUE. MODELS SHOW ANOTHER COLD FRONT MOVING IN.
&&
.AVIATION /05Z WEDNESDAY THROUGH SUNDAY/...
LOW CIGS AND FOG WILL SUPPORT REDUCED FLYING CONDS ACROSS THE
ENTIRE AIRSPACE OVER NIGHT..WIDESPREAD MVFR AND IFR OR LOWER
ACROSS HIGHER ELEVATIONS. CONDS CAUSED BY FRONTAL BOUNDARY VCNTY
STATE AND ABUNDANT LOW LEVEL MOISTURE FROM ONGOING SHOWERS AND
THOSE FROM EARLIER TODAY.
WINDS WILL REMAIN LIGHT INTO WED.
OUTLOOK...
WED...WIDESPREAD MVFR/IFR IN SHRA/PERIODS OF RA.
THU...REDUCTIONS LIKELY IN SCT SHRA.
FRI...REDUCTIONS LIKELY IN SHRA...ESPECIALLY DURING THE
AFT. CHC OF THUNDER AFT.
SAT-SUN...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT/FITZGERALD
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/DEVOIR
LONG TERM...LAMBERT/MARTIN
AVIATION...DEVOIR/GARTNER
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
434 AM CDT WED APR 8 2015
.DISCUSSION...
AS OF 4AM...TEMPERATURES ARE MILD ONCE AGAIN THIS MORNING WITH
READINGS MAINLY IN THE MID TO UPPER 60S ACROSS THE REGION. EARLIER
CONVECTION NEAR THE SOUTHERN KANSAS/MISSOURI BORDER HAS WEAKENED
SIGNIFICANTLY IN THE LAST COUPLE OF HOURS WITH ONLY LIGHT SHOWERS
DEVELOPING TO THE SOUTH OF THE LEFTOVER COMPLEX. A BROAD AREA OF
SCATTERED SHOWERS AND THUNDERSTORMS WERE MOVING OVER PORTIONS OF
CENTRAL AND NORTHEAST ARKANSAS ASSOCIATED WITH A WEAK SHORTWAVE
EMBEDDED IN THE MEAN FLOW. WATER VAPOR IMAGERY ALSO SHOWS A LARGE
CUTOFF LOW ROTATING OVER THE GREAT BASIN THIS MORNING. THIS
FEATURE WILL BE MAIN WEATHER MAKER ACROSS OUR AREA OVER THE NEXT
48 HOURS OR SO.
SHORT TERM...TODAY THROUGH FRIDAY...
THE HRRR HI-RES SHORT TERM MODEL INDICATES THAT SHOWERS AND
SCATTERED THUNDERSTORMS WILL MOVE THROUGH THE MID-SOUTH AGAIN
THIS MORNING. COVERAGE IS EXPECTED TO LESS THAN YESTERDAY...BUT
WILL STILL WARRANT A 20 POP. BY EARLY AFTERNOON...SHOWERS WILL
EXIT THE AREA AND SLIGHT UPPER LEVEL RIDGING WILL RESULT IN
CLEARING SKIES AND VERY WARM CONDITIONS FOR THIS TIME OF YEAR.
READINGS WILL BE IN THE LOW TO MID 80S THIS AFTERNOON...WHICH IS
AS MUCH AS 15 DEGREES ABOVE THE CLIMATOLOGICAL NORMAL FOR THIS
TIME OF YEAR AND NEAR RECORD HIGHS.
BY LATE TONIGHT...MODELS ARE IN REASONABLE AGREEMENT THAT THE
UPPER LEVEL CLOSED LOW OUT WEST WILL EVOLVE INTO AN OPEN WAVE AS
IT MOVES ACROSS THE ROCKIES...AND SURFACE LOW PRESSURE WILL
DEVELOP NEAR THE OKLAHOMA PANHANDLE. THIS SURFACE LOW WILL MOVE
ACROSS THE CENTRAL PLAINS AND INTO THE GREAT LAKES REGION FROM
THURSDAY MORNING AND INTO FRIDAY. AS IT DOES...A STRONG COLD FRONT
WILL SWEEP ACROSS THE MISSISSIPPI VALLEY AND INTERACT WITH A
MODERATELY UNSTABLE AIRMASS. MLCAPE VALUES APPROACHING 2000 J/KG
AND A 50 KT MID LEVEL JET WILL SUPPORT AT LEAST A FEW STRONG TO
SEVERE STORMS. STORM MODE IS STILL A LITTLE UNCLEAR AT THE
MOMENT...BUT IT DOES APPEAR SOME STORMS COULD DEVELOP AHEAD OF THE
LINE AS HEIGHT FALLS OVERSPREAD THE REGION...BEFORE CONGEALING
INTO A QLCS STRUCTURE BY LATE THURSDAY EVENING. DAMAGING WINDS AND
LARGE HAIL LOOK TO BE THE MAIN THREATS...WITH A SECONDARY THREAT
OF FLASH FLOODING. TORNADO THREAT LOOKS VERY MINIMAL...AS THE
FAVORABLE JET STRUCTURE REMAINS WELL TO OUR NORTH. WILL CONTINUE
TO MAKE A MENTION OF SEVERE STORMS IN THE HWO WITH THE BEST
CHANCES REMAINING OVER NORTHEAST ARKANSAS...THE MISSOURI
BOOTHEEL...AND PORTIONS OF NORTHWEST TENNESSEE.
BY FRIDAY AFTERNOON...THE FRONT WILL PUSH TO THE SOUTH AND EAST
AS SURFACE HIGH PRESSURE BUILDS IN. TEMPERATURES WILL BE MILD
DURING THE DAY WITH UPPER 60S AND LOWER 70S EXPECTED.
SATURDAY WILL BE A BEAUTIFUL MILD SPRING DAY WITH LOW HUMIDITY...
TEMPERATURES IN THE LOWER 70...AND ABUNDANT SUNSHINE.
LONG TERM...SUNDAY THROUGH EARLY NEXT WEEK...
A STALLED COLD FRONT TO OUR SOUTH WILL PUSH NORTH AS A WARM FRONT
ON SUNDAY MORNING. AS IT DOES...SHOWERS AND THUNDERSTORMS WILL
OVERSPREAD THE REGION BY THE AFTERNOON HOURS. SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO CONTINUE ON MONDAY BEFORE A COLD
FRONT PUSHES THROUGH THE MID-SOUTH BY TUESDAY. CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO MIDWEEK AS RETURN FLOW
REMAINS DOMINANT ACROSS THE REGION.
AC3
&&
.AVIATION...
06Z TAF SET
VFR CONDITIONS PREVAIL AT ALL TAF SITES TONIGHT. HI RES GUIDANCE
SHOWS SOME SHOWER DEVELOPMENT DURING THE EARLY MORNING SO HAVE
ADDED -RA TO THE TEMPO GROUP BETWEEN 09 AND 12Z FOR JBR AND MEM.
THIS SHOULD MOVE OUT QUICKLY WEDNESDAY MORNING. MVFR CONDITIONS
ARE POSSIBLE DURING THIS PERIOD AS WELL. THIS WILL PERSIST
THROUGH THE EARLY MORNING HOURS BUT LIFT AS THE DAY PROGRESSES.
VFR CONDITIONS ARE EXPECTED AFTER 18Z AT ALL SITES. WINDS WILL BE
STRONG OUT OF THE SOUTH NEAR 15 KTS WITH GUSTS NEAR 20 KTS.
TVT
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
458 AM CDT Wed Apr 8 2015
.SHORT TERM...
(Today and Tonight)
...Severe weather possible this afternoon/evening...
The forecast challenges are plentiful through the next 24 hours. The
TTU WRF and HRRR models indicate showers should be developing to our
southwest at 4 AM, moving into the region from west to east this
morning through mid-afternoon. They then try to re-develop
convection to our west by late afternoon, with this convection
dissipating before midnight as it approaches our western counties.
Conversely, the NAM/GFS/ECMWF all show nothing for this morning
through mid afternoon, and then develop convection from mid-
afternoon through midnight at varying locations/intensities across
the region. Given the current satellite imagery and upstream
observations, we`ll lean more towards this scenario.
The NAM/GFS have also trended significantly farther west with the
dryline position this afternoon. The ECMWF brings it farther east
with it positioned along a line from eastern Haskell County, to San
Angelo, to west of Ozona. We`ll take a middle-ground approach with
the expectation of the dryline halting its eastward progression,
being located along the western edge of the forecast area. A
strong cap will remain in place for much of the day. By late
afternoon/early evening, a mid-level jet streak will approach the
area from the southwest. Increasing ascent from this, afternoon
mixing, and convergence along the dryline, may be sufficient to
weaken the cap enough for a few storms to develop.
If this occurs, the environment will be characterized by 1500-2500
J/kg of SBCAPE (possibly more if skies are less cloudy than
currently forecast), steep mid-level lapse rates near 8 C/km, with
0-6km effective shear values of 40-55 kts. With this type of setup,
storms would rapidly become severe/supercells with large hail and
damaging winds the main concerns. Soundings also show low-level
winds backing to the southeast, which really increases 0-3km
helicity values making isolated tornadoes a possibility as well,
especially across the northwestern this of the area which is closer to
the track of the mid-level disturbance.
.LONG TERM...
(Thursday through Tuesday)
Rain chances remain in most periods of the long term. Another cold
front will push across West Central Texas on Thursday and bring
cooler air, and it will enhance the rain potential for Friday
through the weekend. A developing upper-level disturbance well to
our west will also enhance the rain potential by creating
southwest flow aloft, where embedded minor disturbance will move
across Texas. Isentropic upglide will be best across our southern
counties from Friday through the weekend. Thus, the best chance
for rain will be there. The ECMWF is more aggressive than the GFS
regarding QPF amounts for Friday through the weekend, and the
ECMWF indicates better divergence aloft over Texas for those
periods. So, continuing the best rain chances across our southern
counties looks best. Plus, continuing a PoP forecast closer to
the ECMWF looks better than something closer to the drier GFS.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 84 65 86 55 73 / 30 40 5 10 20
San Angelo 84 65 86 57 74 / 40 40 10 10 40
Junction 83 64 87 61 75 / 30 30 30 10 50
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Doll/Huber
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
101 AM CDT WED APR 8 2015
.AVIATION...
MVFR CIGS WILL DIP DOWN INTO IFR AFTER 08-09Z FOR THE I-35 TAF
SITES...BUT LATER TOWARD 13Z AT KDRT. THEN LOOK FOR CIGS TO LIFT
BACK INTO MVFR BY 18Z...THEN BECOME SCT BY 20Z. WINDS WILL BE
S-SE AND FAIRLY STEADY AT 10-15 KTS THROUGH THE FORECAST PERIOD.
&&
.PREV DISCUSSION... /ISSUED 703 PM CDT TUE APR 7 2015/
AVIATION... /00Z TAF UPDATE/
CONVECTION OVER MEXICO IS NOT ACCOUNTED FOR IN THE DRT IN THIS TAF
UPDATE AS MOST OF THE MODEL DATA SHOWS LITTLE OR NO ACTIVITY
LATER THIS EVENING. AN OUTLIER IS THE HRRR WHICH SHOWS A SMALL
COMPLEX DEVELOP AND POSSIBLY IMPACT AREAS ALONG THE RIO GRANDE
LATE TONIGHT. MODEL GUIDANCE SUGGESTS MVFR CIGS WILL ARRIVE BY
MIDNIGHT AGAIN AND LOWERS BOTH CIGS AND VSBYS INTO IFR CATEGORIES
EARLY WEDNESDAY. WILL LEAN ON PERSISTENCE TO KEEP VSBYS A BIT
HIGHER. AS WITH TODAY...MUCH OF THE DAY WEDNESDAY SKIES SHOULD BE
FILLED WITH AN MVFR CIG. WINDS SHOULD ALSO FOLLOW A DIURNAL
PERSISTENCE TREND.
PREV DISCUSSION... /ISSUED 310 PM CDT TUE APR 7 2015/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...STRATOCU HAS
BEEN SLOWER TO ERODE ALONG THE RIO GRANDE THAN EXPECTED THIS
AFTERNOON...BUT SHOULD EVENTUALLY SCATTER OUT THROUGH THE LATE
AFTERNOON HOURS. ISOLATED CONVECTION BEGINNING TO DEVELOP ALONG
THE HIGHER TERRAIN IN MEXICO. CAN NOT RULE AN ISOLATED STORM
CROSSING INTO VAL VERDE COUNTY EARLY THIS EVENING...BUT CAP MAY
HOLD...ESPECIALLY GIVEN AFOREMENTIONED CLOUDS THAT WERE SLOW TO
ERODE. STRATUS RE-DEVELOPS OVERNIGHT AND SCATTERS TOMORROW
AFTERNOON SIMILAR TO TODAY. OTHERWISE WARM AND BREEZY TOMORROW.
THE DRY LINE ADVANCES SLIGHTLY FARTHER EAST THURSDAY AFTERNOON...
AND WITH WEAK MID LEVEL DISTURBANCE THE CAP DOES ERODE LATE
AFTERNOON ACROSS THE FAR WESTERN AREAS. COULD SEE ISOLATED STORMS
DEVELOPING OVER THE FAR NORTHERN HILL COUNTRY AND EDWARDS PLATEAU
TOMORROW AFTERNOON ADVANCING SOUTHEAST INTO THE SOUTHERN HILL
COUNTRY TOMORROW EVENING. AT THE MOMENT UNSURE IF STORMS WILL HOLD
TOGETHER INTO THE I-35 CORRIDOR LATE EVENING GIVEN THE CAP. CAN
NOT RULE OUT THE POSSIBILITY OF A STRONG STORM OR TWO TOMORROW
AFTERNOON AND EVENING...ESPECIALLY CLOSER TO THE RIO GRANDE.
LONG TERM (THURSDAY THROUGH TUESDAY)...THE DRY LINE ADVANCES ALL
THE WAY INTO VAL VERDE COUNTY ON THURSDAY AFTERNOON....WITH THE
MOIST LOW LEVEL THETA-E RIDGE ALONG AND EAST OF I-35. ANOTHER MID
LEVEL SHORTWAVE AND COOLING HELPS TO ERODE CAP FARTHER INTO THE
CENTRAL AND EASTERN CWA. THE BETTER CHANCES FOR CONVECTION
THURSDAY WILL BE ALONG AND NORTH OF A FREDERICKSBURG TO SAN MARCOS
TO LA GRANGE LINE. A FEW STRONGER STORMS WILL BE POSSIBLE ALONG
AND NORTH OF THIS LINE.
A WEAK COLD FRONT ENTERS THE AREA EARLY FRIDAY MORNING...STALLING
ALONG OR NORTH OF I-10...THEN LIFTING BACK TO THE NORTH FRIDAY
AFTERNOON AND EVENING. MOISTURE POOLING WILL BE BEST ACROSS THE
WESTERN CWA...COINCIDING WITH BROAD LOW LEVEL CONVERGENCE AXIS.
SCATTERED POPS ARE FORECAST FOR THE ENTIRE...BUT BEST CHANCES WILL
BE OUT WEST. BOTH THE ECMWF AND GFS SHOW 700MB SHORTWAVE AND
MOISTURE POOL MOVING NORTHEAST THROUGH THE EDWARDS PLATEAU AND
NORTHERN HILL COUNTRY ON FRIDAY. FORECAST SOUNDINGS INDICANT DEEP
LAYER SHEAR AND INSTABILITY WILL BE SUFFICIENT FOR A FEW STRONG TO
SEVERE STORMS FRIDAY ALONG THE RIO GRANDE...EDWARDS PLATEAU AND
HILL COUNTRY.
DO MAINTAIN POPS INTO SATURDAY GIVEN THE MOISTURE POOL OVER THE
AREA...BUT LACK OF SIGNIFICANT FORCING FEATURE MAY KEEP COVERAGE
IN THE LOW END SCATTERED RANGE. BETTER SHOT FOR SHOWERS AND STORMS
COMES INTO THE FORECAST SUNDAY AND SUNDAY NIGHT...AS SOUTHERN
STREAM UPPER LEVEL SHORTWAVE ACROSS BAJA CALIFORNIA EJECTS EAST
ACROSS TEXAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 85 68 83 68 84 / - - 10 20 40
AUSTIN BERGSTROM INTL AIRPORT 84 68 84 68 82 / - - 10 20 30
NEW BRAUNFELS MUNI AIRPORT 85 68 86 67 85 / - - 10 20 20
BURNET MUNI AIRPORT 84 67 82 66 84 / - - 10 20 40
DEL RIO INTL AIRPORT 84 68 86 67 89 / - 10 20 20 -
GEORGETOWN MUNI AIRPORT 84 68 83 67 83 / - - 10 20 40
HONDO MUNI AIRPORT 85 68 86 67 86 / - - 10 20 20
SAN MARCOS MUNI AIRPORT 84 69 82 68 84 / - - 10 20 30
LA GRANGE - FAYETTE REGIONAL 84 70 84 70 83 / - - 10 10 30
SAN ANTONIO INTL AIRPORT 85 69 86 69 85 / - - 10 20 20
STINSON MUNI AIRPORT 85 69 87 68 85 / - - 10 10 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...26
SYNOPTIC/GRIDS...04
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1145 PM CDT TUE APR 7 2015
.DISCUSSION...
SEE THE 06Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
11-3.9 MICRON IR WAS SHOWING LOW CLOUDS SPREADING INLAND FROM THE
COAST. THE LATEST HIGH RESOLUTION MODELS FORECAST AT LEAST MVFR
CONDITIONS THROUGH ABOUT 15Z. WHILE THERE IS A CHANCE FOR IFR...
DECIDED TO GO WITH PREVAILING MVFR FOR NOW. VFR AND BREEZY
CONDITIONS WILL DEVELOP DURING THE LATE MORNING.
40
&&
.PREV DISCUSSION... /ISSUED 841 PM CDT TUE APR 7 2015/
UPDATE...
SEE EVENING UPDATE.
DISCUSSION...
00Z SOUNDINGS SHOW A CAPPING LAYER BETWEEN 850-700 MB AND
RELATIVELY MEAGER PW VALUES. 850 MB MSTR IS CONFINED TO NE TX TO
SE LA. 700MB LOOKS VERY DRY WITH VERY WARM 700 MB TEMPS EXTENDING
FROM LCH TO BRO. TWEAKED SKY GRIDS AS LOW LEVEL CLOUDS EXPANDING
QUICKLY OVER THE COASTAL COUNTIES. LEANED TOWARD THE HRRR FOR
CLOUD COVER TONIGHT AND FEEL SKIES WILL BECOME MOSTLY CLOUDY PRIOR
TO SUNRISE. MIN TEMPS LOOK ON TRACK SO NO CHANGES PLANNED THERE.
PATCHY FOG STILL BEING REPORTED OVER THE WESTERN GULF SO WILL KEEP
WX GRIDS AS IS.
LOOKING AHEAD...CURRENT FCST SEEMS TO HAVE A GOOD HANDLE ON TWO
WEATHER EVENTS FOR LATER THIS WEEK AND OVER THE WEEKEND. LOOKS
LIKE HIGH RAIN CHANCES FRI-SUN WITH SUNDAY LOOKING INTERESTING FOR
BOTH HEAVY RAIN AND POSSIBLY STRONG STORMS.
THE HIGH AT BUSH IAH TODAY WAS 87 DEGREES. IT IS THE WARMEST
TEMPERATURE SO FAR THIS YEAR. THE LAST TIME HOUSTON REACHED 87
DEGREES WAS ON OCT 16 2014. 43
PREV DISCUSSION... /ISSUED 627 PM CDT TUE APR 7 2015/
DISCUSSION...
SEE THE 00Z AVIATION DISCUSSION BELOW.
40
AVIATION...
THE MODEL FORECAST SOUNDINGS CONTINUE THE THEME OF THE 12Z RAOB
SOUNDINGS AND KEEP A LOW-LEVEL CAPPING INVERSION IN PLACE TONIGHT
INTO WEDNESDAY. EXPECTING MVFR CEILINGS TO DEVELOP BY AROUND 06Z
AND PERSIST THROUGH POSSIBLY AS LATE AS 16Z. SOME LOCATIONS MAY
EXPERIENCE BRIEF IFR CONDITIONS...ALTHOUGH THESE LOOK TO BECOME
MORE PREVALENT AT KLBX AND KGLS. EXPECTING VFR AND BREEZY
CONDITIONS TO DEVELOP DURING THE LATE MORNING WEDNESDAY.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 69 84 70 83 68 / 10 10 20 50 40
HOUSTON (IAH) 69 83 71 83 70 / 10 10 10 30 30
GALVESTON (GLS) 70 79 71 80 71 / 10 10 10 20 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1104 PM MDT TUE APR 7 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 230 PM MDT TUE APR 7 2015
MAIN FORECAST CONCERN CONTINUES TO BE THE PACIFIC STORM SYSTEM
CURRENTLY NEAR THE NORTHERN CALIFORNIA COASTLINE FOR WEDNESDAY AND
THURSDAY. FOR TODAY...LOW STRATUS CLOUD DECK STILL LINGERING
ACROSS WESTERN NEBRASKA AS FAR WEST AS SCOTTSBLUFF. THE FOG HAS
LIFTED FROM THIS MORNING...BUT EXPECT THE FOG TO REFORM TONIGHT.
CURRENT KCYS RADAR LOOP SHOWS SOME RAIN SHOWERS DEVELOPING NEAR
AND SLIGHTLY EAST OF THE LARAMIE RANGE THIS AFTERNOON. CAN NOT
RULE OUT SOME THUNDER INTO THIS EVENING...SO KEPT ISOLATED THUNDER
WITH A 20 TO 30 PERCENT CHANCE OF RAIN SHOWERS MAINLY ALONG AND
EAST OF THE LARAMIE RANGE. THE BEST CHANCE APPEARS TO BE EAST OF
I25.
FOR TONIGHT...ISOLATED RAIN SHOWERS ACTIVITY ACROSS THE HIGH
PLAINS WILL GRADUALLY DISSIPATE OVERNIGHT. FOG WILL REFORM AND
POTENTIALLY PUSH AS FAR WEST AS THE LARAMIE RANGE FOOTHILLS. MODEL
SOUNDINGS ARE MARGINAL FOR SOME DRIZZLE ACROSS WESTERN
NEBRASKA...BUT KEPT LOW POP AND PATCHY/OCCASIONAL DRIZZLE FOR
NOW. DRY AIR JUST ABOVE 750 MB MAY PREVENT WIDESPREAD DRIZZLE FROM
DEVELOPING HOWEVER.
MODELS ARE COMING INTO SLIGHTLY BETTER AGREEMENT REGARDING THE
NORTHWARD TRACK OF THIS STORM SYSTEM...AS THE UPPER LEVEL TROUGH
AXIS INITIALLY MOVES OVER WYOMING...AND THEN DIGS A BIT SOUTHEAST
WEDNESDAY NIGHT DUE TO CYCLOGENESIS OVER EASTERN COLORADO AND
WESTERN KANSAS. WITH THE MORE NORTHWARD TRACK AND RELATIVE
PROGRESSIVE NATURE OF THE SYSTEM...SNOWFALL APPEARS TO BE MUCH LESS
OF A CONCERN COMPARED TO 3 TO 4 DAYS AGO. IN FACT...SOME AREAS
FURTHER SOUTH WILL BE LUCKY TO GET ANYTHING AT ALL FROM THIS
SYSTEM. HOWEVER...TSTORMS MAY DEVELOP ACROSS THE FORECAST AREA
EARLY WEDNESDAY AFTERNOON AND SOME MAY BECOME STRONG OVER THE HIGH
PLAINS. CAPE VALUES AND LI/S ARE NOT TOO IMPRESSIVE...BUT THERE IS
SOME DYNAMIC FORCING WITH THIS STORM SYSTEM. DYNAMICS AND STRONG
WIND SHEAR MAY BE JUST ENOUGH TO TRIGGER A FEW STRONGER STORMS
EAST OF THE LARAMIE RANGE...WITH THE BEST CHANCE OVER WESTERN
NEBRASKA. SOME OF THESE SHOWERS AND STORMS WILL CONTAIN BRIEF
HEAVY RAINFALL...HAIL...AND GUSTY WINDS AS THEY MOVE NORTHEAST
INTO WEDNESDAY EVENING. THE GFS...NAM...AND GEM ALL SHOW A DRY
SLOT MOVING ALONG THE I80 CORRIDOR WHILE THE ECMWF SHOWS THE
PRECIPITATION MORE WIDESPREAD OVER THE HIGH PLAINS. KEPT POP ABOVE
60 PERCENT FURTHER NORTH AND EAST...MAINLY NORTH OF I80 WITH LOWER
POP NEAR THE COLORADO BORDER. COLDER AIR BEHIND THE PACIFIC COLD
FRONT PUSHES INTO THE AREA WEDNESDAY EVENING FROM WEST TO
EAST...WITH RAINFALL CHANGING TO SNOW FROM RAWLINS TO LARAMIE
AROUND SUNSET. THIS COLDER AIR WILL NOT MAKE IT INTO THE HIGH
PLAINS UNTIL LATE WEDNESDAY EVENING. SNOW LEVELS APPEARS TO BE
LOWER AROUND 4500 FEET BY EARLY THURSDAY. MODELS INDICATE THAT
THIS STORM SYSTEM WILL RAPIDLY MOVE EAST INTO THE GREAT PLAINS ON
THURSDAY...GREATLY LIMITING SNOWFALL AMOUNTS. EXPECT MAYBE 1 TO 2
INCHES OF SNOW WEST OF THE LARAMIE RANGE WITH 3 TO 6 INCHES OVER
THE MOUNTAINS. FOR THE HIGH PLAINS...GENERALLY A DUSTING TO UP TO
ONE INCH OF SNOW IS POSSIBLE...MAINLY NEAR THE LARAMIE RANGE AND
AROUND THE PINE AND CHEYENNE RIDGE. HIGH TEMPERATURES ON THURSDAY
WILL BE COOLER...BUT STILL IN THE 40S FOR HIGHS DUE TO SOME LATE
DAY SUNSHINE.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 212 PM MDT TUE APR 7 2015
A FEW MINOR MODEL DIFFERENCES EARLY IN THE FCST PERIOD WITH THE GFS
SHOWING A WEAK MID LEVEL SHORTWAVE DRIFTING ACROSS CENTRAL MT ON FRI
AFTN. THE ECMWF SUGGESTS BROAD RIDGING AND SUBSIDENCE ALOFT...WHICH
WOULD TEND TO BE THE WARMER AND DRIER SOLUTION. THIS IS THE OUTLIER
ATTM SO HAVE KEPT TEMPS ON THE COOLER SIDE OF AVAILABLE GUIDANCE AND
MAINTAINED MENTION OF ISOLATED SHOWERS OVER THE MOUNTAINS. A QUASI-
ZONAL FLOW PATTERN WILL GOVERN THE PATTERN THROUGH THE WEEKEND INTO
EARLY NEXT WEEK. H7-H3 RH PROGS FROM THE GFS/ECM/GEM ALL SUGGEST WE
SHOULD SEE MORE SUNSHINE AS A TRANSITORY RIDGE PASSES OVER THE AREA
AHEAD OF THE NEXT SYSTEM. H7 TEMPS AROUND 3-5 C AND LOW LEVEL DOWNSLOPE
FLOW WILL HELP YIELD 65-75 DEGREE READINGS EAST OF THE LARAMIE
RANGE ON SAT AFTN. A FAIRLY POTENT SHORTWAVE WILL MOVE FROM THE
PACIFIC NORTHWEST INTO THE NORTHERN AND CENTRAL ROCKIES ON
SUN/MON. MEDIUM RANGE GUIDANCE DIFFERS WITH THE TIMING AND
AMPLITUDE OF THIS SYSTEM WITH THE GFS KEEPING MOST OF THE ENERGY
TO OUR NORTH. THAT IS WHERE THE HIGHER CHANCES FOR PCPN COULD
REMAIN AS WELL. DEFINITELY LOOKING AT A WINDIER STRETCH OF DAYS
SUN/MON WITH INCREASING H7-H5 GRADIENTS AND RESULTANT STRONG FLOW
ALOFT. OVERALL EXPECT A PERIOD OF SEASONAL WEATHER CONDITIONS WITH
MINIMAL CHANCES FOR PCPN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1102 PM MDT TUE APR 7 2015
IFR/LIFR CONDITIONS EXPECTED ONCE AGAIN OVERNIGHT WITH EAST TO
SOUTHEAST UPSLOPE FLOW. HRRR GUIDANCE KEEPS LOW CONDITIONS IN
THROUGH MOST OF THE MORNING FOR AREAS EAST OF THE LARAMIE RANGE
BEFORE BREAKING AT 17Z OR SO.
&&
.FIRE WEATHER...
ISSUED AT 212 PM MDT TUE APR 7 2015
LOW FIRE WEATHER CONCERNS FOR THE REST OF THIS WEEK AS A PACIFIC
STORM SYSTEM IMPACTS THE REGION STARTING TOMORROW. COOLER
TEMPERATURES ARE EXPECTED ALONG WITH HIGHER RELATIVE HUMIDITIES
THROUGH FRIDAY. THERE IS A DECENT CHANCE OF RAIN SHOWERS AND
TSTORMS ON WEDNESDAY AS WELL...MAINLY ACROSS WESTERN NEBRASKA.
DRIER WEATHER IS EXPECTED THIS WEEKEND WITH WARMER TEMPERATURES
AND RELATIVE HUMIDITIES TRENDING LOWER.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...TJT
LONG TERM...CLH
AVIATION...GCC
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1051 AM EDT WED APR 8 2015
.SYNOPSIS...
A NEARLY STATIONARY FRONT WILL REMAIN TO THE SOUTH THROUGH
THURSDAY. LOW PRESSURE MOVES THROUGH THE GREAT LAKES WITH A WARM
FRONT APPROACHING THURSDAY NIGHT. THE WARM FRONT PUSHES NORTHWEST
OF THE REGION EARLY FRIDAY WITH LOW PRESSURE DEEPENING IN
SOUTHEAST CANADA. AN ASSOCIATED COLD FRONT WILL MOVE ACROSS FRIDAY
EVENING. A SECONDARY WEAK COLD FRONT MOVES ACROSS SATURDAY WITH
HIGH PRESSURE FROM THE WEST BUILDING INTO THE REGION FOR THE REST
OF THE WEEKEND. HIGH PRESSURE MOVES OFFSHORE EARLY NEXT WEEK
AFTER WHICH LOW PRESSURE APPROACHES FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR THIS UPDATE HAVE CUT BACK SIGNIFICANTLY ON CHANCES OF RAIN OR
DRIZZLE. COOL/DRY AIR DAMMING WEST EXTENDING SW FROM STRONG HIGH
PRESSURE BUILDING ACROSS NEW ENGLAND...WITH THE OKX 12Z SOUNDING
VERY DRY BELOW 900 MB...AND LOW LEVELS FCST TO REMAIN SO THROUGH
MUCH OF TODAY AS THE DAMMING REMAINS IN PLACE. THIS DAMMING SHOULD
SHUNT MOST OF THE PRECIP ASSOCIATED WITH A DEVELOPING WEAK LOW E
OF THE VA CAPE...AND WEAKEN SHOWERS MOVING E FROM THE SUSQUEHANNA
VALLEY IN PA. HRRR STILL DOES FCST SOME OF THIS ACTIVITY TO MAKE
IT INTO AREAS WEST OF NYC THIS AFTERNOON...WITH MORE ISOLD
ACTIVITY FARTHER EAST VIA MOISTURE AND WEAK H7-8 LIFT...SO STILL
HAVE SLIGHT CHANCE POP THIS AFTERNOON FOR SRN CT AND LONG ISLAND.
HIGH TEMPS TODAY WILL LIKELY RUN 10-15 DEGREES BELOW SEASONABLE
TODAY...LOWER/MID 40S. COMBINED WITH NE WINDS OF 15 TO 20 MPH AND
GUSTS TO 30 MPH ALONG THE COAST BETWEEN THE HIGH TO THE NORTH AND
DEVELOPING LOW TO OUR SOUTH...IT WILL BE A RAW DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
MODELS IN GOOD AGREEMENT WITH A DEVELOPING CENTRAL US TROUGH AS A
NORTHERN STREAM SHORTWAVE AND UPPER LOW EJECTING OUT OF THE
ROCKIES PHASE...RESULTING IN AN UPSTREAM GRADUAL RISE IN HEIGHTS
UP THE EASTERN SEABOARD.
RESULTANT LOW PRESSURE TRACKS FROM THE CENTRAL PLAINS TO THE CENTRAL
GREAT LAKES...WITH THE COLD FRONT TO THE SOUTH TONIGHT GRADUALLY
WORKING NORTH TOWARDS THE AREA AS A WARM FRONT LATE THU/THU NIGHT.
MEANWHILE...HIGH PRESSURE WILL ONLY SLOWLY RELENT ITS POSITION ACROSS
THE CANADIAN MARITIMES AND DRIFT OFFSHORE.
THE RESULT WILL BE A CONTINUATION OF STRATUS...PERIODS OF RAIN
SHOWERS...AND AREAS OF DRIZZLE TONIGHT INTO THURSDAY WITH A BRISK
AND CHILLY NE FLOW. WITH NORTHERN STREAM SHORTWAVE PASSING TO THE
EAST BY THURSDAY MORNING...SHOWER ACTIVITY MAY BECOME LESS
WIDESPREAD. THEN INCREASING CHANCE FOR SHOWER ACTIVITY LATE
THURSDAY AND MORE SO THURSDAY NIGHT WITH STRONG WARM AIR
ADVECTION PATTERN DEVELOPING OVER APPROACHING WARM FRONT. MOST
WIDESPREAD DRIZZLE WILL LIKELY BE ACROSS AREAS NW AND W OF NYC
WITH SOME OROGRAPHIC LIFT. HAVE ASSIGNED POPS BASED ON ABOVE
THINKING.
ALTHOUGH THERMAL PROFILES SUPPORT LIQUID PRECIPITATION FOR THE
MOST PART...MODELS ARE INDICATING A DEVELOPING LOW-LEVEL COLD
LAYER BETWEEN 975-900 MB AFTER MIDNIGHT INTO EARLY THURSDAY
MORNING...WHICH COULD RESULT IN FREEZING RAIN ACROSS ELEVATIONS
ABOVE 500-750 FT. IF STRENGTH OF COLD LAYER IS CLOSER TO NAM
SOUNDINGS...POTENTIAL FOR A BIT OF SLEET ACROSS INTERIOR TONIGHT.
WILL HOLD OFF ON ANY ADVISORIES FOR THE FREEZING RAIN AT THIS
POINT WITH LIMITED COVERAGE...POTENTIAL FOR SLEET...AND MARGINALLY
COLD CONDITIONS.
HIGH TEMPS THURSDAY WILL LIKELY RUN 10-15 DEGREES BELOW SEASONABLE
ONCE AGAIN (LOWER TO MID 40S)...WITH A CONTINUATION OF THE RAW
CONDITIONS WITH GUSTY NE WINDS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
OVERALL IN THE UPPER LEVELS...THE JET STREAM WILL BE
NORTH OF THE REGION...MOVING INTO THE REGION FRIDAY NIGHT AND JUST
SOUTH OF THE REGION FOR THE WEEKEND BEFORE RISING BACK NORTH EARLY
NEXT WEEK.
IN THE MID LEVELS...THE LONGWAVE RIDGE MOVES OFF THE EAST
COAST THURSDAY NIGHT THROUGH FRIDAY. THERE IS AN EMBEDDED SUBTLE
SHORTWAVE WITH A STREAK OF POSITIVE VORTICITY ADVECTION FRIDAY
WHICH WILL HELP ENHANCE LIFT FOR SHOWERS AND POSSIBLE
THUNDERSTORMS NEAR AREAS WHICH HAVE GREATER MAX TEMPS. A LARGER
SHORTWAVE APPROACHES SATURDAY AND MOVES THROUGH LATE IN THE DAY
WITH A LONGWAVE RIDGE SETTLING IN THEREAFTER.
AT THE SURFACE...THE APPROACH OF A WARM FRONT ASSOCIATED WITH A
PARENT LOW MOVING THROUGH THE GREAT LAKES FRIDAY NIGHT WILL KEEP A
MILD AIR MASS IN PLACE. WARM AND MOIST AIR ADVECTION INCREASE
GOING INTO FRIDAY ONCE THE WARM FRONT IS NORTH OF THE REGION.
A PRETTY STEEP INVERSION WILL BE SET UP AROUND 925MB WHERE TEMPS
COULD REACH AS HIGH AS 19 DEGREES CELSIUS. SOME UNCERTAINTY ON
GROUND TEMPS AND HOW MUCH OF THE HIGHER TEMPS ABOVE MIX DOWN. THE
SOUTHERLY FLOW THROUGHOUT THE ATMOSPHERE AND APPROACH OF A WARM
FRONT SUGGEST AN ADVECTION FOG SETUP. INDICATED PATCHY FOG
DEVELOPING THURSDAY NIGHT INTO FRIDAY AND THEN AREAS OF FOG FRIDAY
ON THE WATERS WHICH WILL PROBABLY TAKE SOME TIME TO DISSIPATE
THROUGH THE DAY. IT IS TOO EARLY TO INDICATE EXPLICITLY IN
FORECAST...BUT THERE IS THE POSSIBILITY OF DENSE FOG.
IN TERMS OF PRECIPITATION...MODELS HAVE SOME DISAGREEMENT WITH
SHOWER DEVELOPMENT ALONG WARM FRONT BUT ENOUGH OF SIGNAL SUGGESTS
SHOWERS OR DRIZZLE WILL BE LIKELY THURSDAY NIGHT INTO FRIDAY. THEN
A LULL IN ACTIVITY WITH THE AREA BEING IN THE WARM SECTOR WITH A
CHANCE OF SHOWERS...BEFORE LIKELY SHOWERS AND POSSIBLE
THUNDERSTORMS MOVE ACROSS FRIDAY AFTERNOON INTO THE EVENING AHEAD
OF A COLD FRONT.
THE COLD FRONT MOVES ACROSS FRIDAY EVENING WITH HIGH PRESSURE TO THE
WEST STARTING TO MOVE EAST. HOWEVER...IT WILL NOT BE THAT PROMINENT
INITIALLY AS THE SHORTWAVE TROUGH AND A SECONDARY WEAK COLD FRONT
MOVE ACROSS SATURDAY. MAINLY DRY CONDITIONS SATURDAY ARE ANTICIPATED
BUT CANNOT RULE OUT A SHOWER ASSOCIATED WITH THE PASSAGE OF FRONT
AND SHORTWAVE...PROBABLY ACROSS THE LOWER HUDSON VALLEY WHERE BETTER
DYNAMICS ARE CONVEYED.
DRY WEATHER FOR SUNDAY AND MONDAY WITH HIGH PRESSURE TAKING OVER.
OVERALL...TEMPS LOOK TO BE A FEW DEGREES ABOVE NORMAL.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
HIGH PRESSURE BUILDS TO THE NORTH THEN NORTHEAST THROUGH TONIGHT.
MEANWHILE...A STATIONARY FRONT REMAINS TO OUR SOUTH...WITH WAVES
OF LOW PRESSURE RIDING ALONG IT.
VFR...WITH CEILINGS GENERALLY BETWEEN 3500-6000FT TODAY. CEILINGS
DECREASE TO MVFR LATE THIS AFTERNOON AND THIS EVENING...THEN TO
IFR OVERNIGHT.
NE-ENE WINDS 10-15KT AT CITY/CT/LONG ISLAND TERMINALS...SLIGHTLY
LESS AT THE TERMINALS NORTH NYC. WINDS HAVE BECOME A BIT GUSTY
WITH SPEEDS INTO THE UPPER TEENS AND LOWER 20S. WINDS BEGIN TO
DIMINISH THIS AFTERNOON AT MOST TERMINALS...EXCEPTION IS COASTAL
CT...WHERE WINDS INCREASE THIS EVENING...WITH GUSTS TO 25-30KT.
PEAK GUSTS COULD BE UP TO 5 TO MAYBE 10 KT HIGHER THAN WHAT IS IN
THE TAFS.
WINDS THEN DIMINISH FROM MID-LATE EVENING ON...FAIRLY QUICKLY
LOSING THEIR GUSTINESS.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT:
HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILINGS. TIMING OF CHANGES IN WIND SPEED...DIRECTION AND
ON/OFFSET OF GUSTS COULD BE OFF +/- 2-3 HOURS.
KLGA FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILINGS. TIMING OF CHANGES IN WIND SPEED...DIRECTION AND
ON/OFFSET OF GUSTS COULD BE OFF +/- 2-3 HOURS.
KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILINGS. TIMING OF CHANGES IN WIND SPEED...DIRECTION AND
ON/OFFSET OF GUSTS COULD BE OFF +/- 2-3 HOURS.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS YELLOW...WHICH
IMPLIES SLANT RANGE VISIBILITY 4-6SM OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILINGS. TIMING OF CHANGES IN WIND SPEED...DIRECTION AND
ON/OFFSET OF GUSTS COULD BE OFF +/- 2-3 HOURS.
KHPN FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILINGS. TIMING OF CHANGES IN WIND SPEED...DIRECTION AND
ON/OFFSET OF GUSTS COULD BE OFF +/- 2-3 HOURS.
KISP FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILINGS. TIMING OF CHANGES IN WIND SPEED...DIRECTION AND
ON/OFFSET OF GUSTS COULD BE OFF +/- 2-3 HOURS.
.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
.THURSDAY-FRIDAY MORNING...MVFR TO VFR AT DAY...THEN MVFR TO IFR
AT NIGHT IN PERIODS -RA/DZ. E-NE WINDS G15-20KT THURSDAY. LLWS
POSSIBLE S/E TERMINALS LATE THURSDAY NIGHT/FRIDAY MORNING.
.FRIDAY AFTERNOON/NIGHT...MVFR OR LOWER IN SHRA AND SLIGHT CHANCE
TSTMS INTO FRIDAY EVENING...THEN BECOMING VFR. NW WINDS G20-25KT
POSSIBLE FROM MID FRIDAY EVENING ON.
.SATURDAY-SUNDAY...VFR. NW WINDS G15-20KT POSSIBLE DURING THE
DAYLIGHT HOURS SATURDAY.
&&
.MARINE...
A TIGHTENING PRESSURE GRADIENT AS HIGH PRESSURE BUILDS INTO NEW
ENGLAND AND A WEAK LOW DEVELOPS ALONG THE MID ATLANTIC COAST
EXPECTED TO DEVELOP MARGINAL GALE CONDITIONS ON THE OCEAN WATERS
AND SCA CONDITIONS OVER THE REMAINDER OF THE WATERS THIS
MORNING...AND CONTINUING INTO THIS EVENING.
A GRADUAL SLACKENING OF THE GRADIENT EXPECTED LATE TONIGHT INTO
THU AS SURFACE WAVE DISSIPATES AND HIGH PRESSURE SLIDES FURTHER
OFFSHORE. THIS SHOULD ALLOW GALE CONDITIONS TO FALL TO SCA ON THE
OCEAN LATE THIS EVENING. SCA WINDS LIKELY CONTINUE ON THE OCEAN
WATERS THRU THU...BUT LOWER CONFIDENCE ON THE NEARSHORE WATERS
SEEING SCA CONDITIONS CONTINUE ON THU.
OCEAN SEAS EXPECTED TO BUILD TO 6 TO 10 FT WITH LONG PERIOD EASTERLY
SWELLS TODAY INTO TONIGHT...AND LIKELY SLOW TO SUBSIDE ON THU.
SCA CONDITIONS FORECAST ON THE OCEAN MUCH OF THE PERIOD THURSDAY
NIGHT THROUGH SATURDAY NIGHT. SCA CONDITIONS FORECAST FOR ALL WATERS
SATURDAY. SUB SCA CONDITIONS FORECAST OVERALL FOR SUNDAY.
&&
.HYDROLOGY...
RAINFALL OF 1/10 TO 2/10 INCH EXPECTED THROUGH THU. RAINFALL OF
AROUND 1/2 INCH LIKELY THU NIGHT THROUGH FRI NIGHT.
HYDROLOGIC IMPACTS NOT EXPECTED.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEB SITE.
&&
.TIDES/COASTAL FLOODING...
NE WINDS OF 15-25 KT TODAY INTO TONIGHT WILL HAVE WATER LEVELS
APPROACHING MINOR FLOODING LEVELS ACROSS THE MOST VULNERABLE AREAS
OF THE WESTERN GREAT SOUTH BAY DURING THE LATE TONIGHT HIGH TIDE
CYCLE. THERE IS A LOW PROBABILITY THAT MINOR FLOODING THRESHOLDS
ARE TOUCHED IN THESE AREAS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ338.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR ANZ330-335-
340-345.
GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR ANZ350-353-355.
&&
$$
SYNOPSIS...GOODMAN/NV
NEAR TERM...GOODMAN/NV
SHORT TERM...NV
LONG TERM...JM
AVIATION...BC/MALOIT
MARINE...GOODMAN/JM/NV
HYDROLOGY...GOODMAN/JM/NV
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1046 AM EDT WED APR 8 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL THROUGH FRIDAY. A COLD FRONT
WILL SHIFT THROUGH THE AREA FRIDAY NIGHT INTO SATURDAY...THEN STALL
SOUTH OF THE REGION ON SUNDAY BEFORE LIFTING BACK NORTH THROUGH THE
AREA AS A WARM FRONT ON MONDAY. ATLANTIC HIGH PRESSURE WILL THEN
PREVAIL THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATE THIS MORNING...SKIES HAVE CLEARED OUT ACROSS THE FORECAST
AREA AND PLENTIFUL SUNSHINE WILL PREVAIL INTO THE AFTERNOON. THE
OVERALL SETUP CONTINUES TO LOOK A LOT LIKE SUMMER. ALOFT...THE
REGION IS WITHIN THE BROAD RIDGE AXIS AND RELATIVELY WEAK WESTERLY
FLOW. AT THE SURFACE...ATLANTIC HIGH PRESSURE PREVAILS WITH A
RATHER BENIGN PATTERN. WITHIN THE BROADLY ANTICYCLONIC FLOW
ALOFT...THE MODELS SHOW A CLEAR AREA OF NVA THAT CURRENTLY SITS
ACROSS MUCH OF GEORGIA AND EASTERN ALABAMA. THIS WILL SLOWLY DRIFT
EASTWARD TODAY...AND SHOULD HELP TO KEEP CONVECTIVE DEVELOPMENT AT
A MINIMUM FOR MOST OF SOUTHEAST GEORGIA. FURTHER TO THE
EAST...THERE IS A WEAK VORT MAX ON THE LEADING EDGE OF THE
NVA...WHICH MAY HELP TO FOCUS CONVECTIVE DEVELOPMENT ACROSS INLAND
PORTIONS OF THE TRI-COUNTY AND SOUTHEAST SOUTH CAROLINA. THERE
SHOULD BE A ROBUST AND PROGRESSIVE SEA BREEZE THIS AFTERNOON WITH
LAND TEMPERATURES REACHING THE MID 80S AND WATER TEMPERATURES IN
THE MID 60S. THIS WILL HELP TO KEEP SHOWER/THUNDERSTORM
DEVELOPMENT FURTHER INLAND AS WELL.
CONCERNING THE THERMODYNAMIC ENVIRONMENT...TEMPERATURES REACHING
THE MID/UPPER 80S WILL RESULT IN A MUCH MORE UNSTABLE AIRMASS THAN
PREVIOUS DAYS. IN FACT...MODIFIED HRRR AND RAP SOUNDINGS GIVE CAPE
VALUES ON THE ORDER OF 2000-2300 J/KG. THE COLUMN DRIES OUT A BIT
TOO AND DCAPES ARE PROGGED TO BE IN EXCESS OF 1000 J/KG. LAPSE
RATES STEEPEN TO AROUND -6 C/KM AND THERE IS A NICE SEPARATION
BETWEEN THE FREEZING LEVEL AND THE WET BULB ZERO. SO...EVEN THOUGH
COVERAGE WILL BE SCATTERED AT BEST...THERE IS THE POTENTIAL FOR A
COUPLE OF STRONG TO SEVERE STORMS. IT APPEARS CONVECTIVE
INITIATIONWILL BEGIN AROUND 19Z...AND POPS HAVE BEEN ADJUSTED TO
CONTAIN THE CHANCES JUST TO THE TRI-COUNTY AND SOUTHEAST SOUTH
CAROLINA AREA. WILL MAINTAIN THE MENTION IN THE HWO.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
TONIGHT...EARLY EVENING CONVECTION WILL DISSIPATE WELL INLAND WITH
THE LOSS OF INSOLATION. WARM AND HUMID CONDITIONS WILL LINGER WITH
LOWS FALLING INTO THE LOWER-MID 60S. COULD SEE ANOTHER AROUND OF
PATCHY GROUND FOG IN SOME LOCATIONS...ESPECIALLY THAT RECEIVES
RAINFALL THIS AFTERNOON...BUT THE FOG DOES NOT LOOK SIGNIFICANT
ATTM.
THURSDAY...THE AREA WILL REMAIN ALONG THE WESTERN EDGE OF ATLANTIC
HIGH PRESSURE AND UNDER A MID LVL RIDGE OF HIGH PRESSURE EXTENDING
NORTHWARD FROM THE GULF OF MEXICO. THE BULK OF PRECIP ACTIVITY
SHOULD SHIFT SLIGHTLY MORE INLAND THAN PREVIOUS DAYS AS THE MID LVL
RIDGE EXPANDS OVER THE AREA WELL AHEAD OF A LOW PRESSURE TROUGH
DIGGING OVER THE CENTRAL UNITED STATES. THE PATTERN WILL RESULT IN
WARM TEMPS...WITH HIGHS IN THE MID TO UPPER 80S OVER MOST LOCATIONS.
TEMPS WILL REMAIN COOLER ALONG THE COAST GIVEN AN ONSHORE FLOW.
SUFFICIENT HEATING AND MOISTURE WILL SUPPORT A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS AWAY FROM THE COAST...BUT ACTIVITY WILL
LIKELY BE DRIVEN BY AN AFTERNOON SEABREEZE GIVEN THE LACK OF LARGER
SCALE FORCING. EXPECT MOST PRECIP TO DIMINISH WITHIN A FEW HOURS OF
SUNSET. OVERNIGHT LOWS SHOULD RANGE IN THE MID 60S. WE COULD SEE
SOME PATCHY FOG DEVELOP LATE WHILE WINDS ARE LIGHT/CALM AND DEWPTS
REMAIN IN THE MID 60S.
FRIDAY...ANOTHER WARM DAY IS ANTICIPATED WELL AHEAD OF COLD FRONT
THAT WILL MAKE WAY TO THE REGION LATE. EXPECT HIGH TEMPS TO WARM IN
THE MID/UPPER 80S FOR MOST LOCATIONS...EVEN AS CLOUD COVER INCREASES
FROM THE WEST. CHANCES OF SHOWERS AND/OR THUNDERSTORMS WILL BE
POSSIBLE...ESPECIALLY LATE AS MOISTURE DEEPENS AND MID LVL FORCING
BEGINS TO INCREASE ALONG AND AHEAD OF A SFC COLD FRONT MAKING WAY
INTO THE AREA FRIDAY NIGHT. AT THIS TIME...THE THREAT OF SEVERE
WEATHER REMAINS LOW GIVEN THE TIMING OF FROPA DURING THE OVERNIGHT
PERIOD. HOWEVER...THERE IS A LOW CHANCE OF A FEW STRONGER
THUNDERSTORMS GIVEN SBCAPES APPROACHING 1000-1250 J/KG AND 20-30 KT
LOW/MID LVL WIND FIELDS SHIFTING OVER THE AREA FRIDAY EVENING.
OVERNIGHT LOWS SHOULD REMAIN MILD UNTIL FROPA...IN THE MID 60S FOR
MOST LOCATIONS
SATURDAY...A COLD FRONT WILL PUSH THROUGH THE AREA EARLY WITH AT
LEAST CHANCES OF SHOWERS AND/OR THUNDERSTORMS AS FROPA OCCURS. DRYER
AND COOLER CONDITIONS WILL FOLLOW THE FRONT AS HIGH PRESSURE BUILDS
IN FROM THE NORTH. OVERALL HIGH TEMPS SHOULD PEAK NEAR 80 FOR
LOCATIONS AWAY FROM THE COAST...BUT WILL LIKELY BE ON A COOLING
TREND BY MID AFTERNOON OVER NORTHERN AREAS WHERE SFC WINDS SHIFT TO
NORTHEAST BEHIND THE FRONT. BY SATURDAY EVENING...MOST PRECIP
ACTIVITY WILL LIKELY BE FOCUSED IN SOUTHEAST GEORGIA...WHERE THE
FRONT CONTINUES A SOUTHWARD SHIFT BEFORE STALLING WELL SOUTH OF THE
AREA.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
A WEAKENED/STALLED FRONT WILL BE POSITIONED SOUTH OF THE AREA
THROUGH SUNDAY...WHILE A WEDGE OF HIGH PRESSURE BUILDS FROM THE
NORTH. TEMPS WILL BE COOLER...WITH OVERALL HIGHS IN THE MID 70S OVER
MOST LOCATIONS. A SLIGHT CHANCE TO CHANCE OF SHOWERS AND/OR
THUNDERSTORMS WILL MAINLY BE CONFINED TO LOCATIONS SOUTH OF
INTERSTATE 16 IN SOUTHEAST GEORGIA THROUGH EARLY MONDAY. CHANCES OF
SHOWERS AND THUNDERSTORMS SHOULD RETURN TO MOST AREAS ON MONDAY AS
THE STALLED FRONT LIFTS BACK NORTH AS A WARM FRONT WELL AHEAD OF A
DEEPENING LOW PRESSURE SYSTEM OVER THE CENTRAL UNITED STATES. HIGH
TEMPS SHOULD THEN RETURN INTO THE 80S THROUGH THE MIDDLE OF NEXT
WEEK AS THE AREA REMAINS SITUATED ALONG THE WESTERN EDGE OF ATLANTIC
HIGH PRESSURE AND STRONG RIDGING ALOFT.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
VFR. STILL LOOKS LIKE THE BEST CHANCES FOR TSTMS WILL REMAIN WEST
OF THE TERMINALS THIS AFTERNOON.
EXTENDED AVIATION OUTLOOK...LOW CHANCES OF FLIGHT RESTRICTIONS
THURSDAY AND FRIDAY WITH AFTERNOON SHOWERS AND/OR THUNDERSTORMS.
FLIGHT RESTRICTION CHANCES INCREASE FRIDAY NIGHT INTO SATURDAY
SATURDAY AS A COLD FRONT PASSES OVER BOTH TERMINALS.
&&
.MARINE...
THROUGH TONIGHT...SOUTHERLY WIND REGIME WILL PERSIST. WINDS WILL
GENERALLY REMAIN 10 KT OR LESS WITH SEAS 2-4 FT.
THURSDAY THROUGH MONDAY...CONDITIONS WILL REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS THROUGH LATE WEEK ALONG THE WESTERN EDGE OF ATLANTIC
HIGH PRESSURE. IN GENERAL...A SOUTHERLY WIND WILL REMAIN AT OR BELOW
15 KTS OUTSIDE DAILY SHOWERS AND/OR THUNDERSTORMS. BRIEF SURGES AND
SLIGHT CHANGES IN WIND DIRECTION SHOULD OCCUR NEAR AFTERNOON
SEABREEZE CIRCULATIONS. SEAS WILL BE NO HIGHER THAN 4 FT. WINDS/SEAS
SHOULD THEN INCREASE/BUILD THIS WEEKEND AS A COLD FRONT APPROACHES
FROM THE NORTHWEST FRIDAY...THEN SHIFTS OVER THE COASTAL WATERS
FRIDAY NIGHT INTO EARLY SATURDAY. HOWEVER...CONDITIONS ARE EXPECTED
TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS OUTSIDE THUNDERSTORM
ACTIVITY. A FEW THUNDERSTORMS COULD BE STRONG DURING FROPA FRIDAY
NIGHT. WINDS WILL SHIFT TO NORTH/NORTHEAST BEHIND THE FRONT AS IT
STALLS SOUTH OF THE COASTAL WATERS SATURDAY NIGHT AND SUNDAY. THE
STALLED FRONT IS THEN EXPECTED TO LIFT BACK NORTH AS A WARM FRONT ON
MONDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...BSH
SHORT TERM...DPB
LONG TERM...DPB
AVIATION...ST
MARINE...ST/DPB
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
648 AM EDT WED APR 8 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL THROUGH FRIDAY. A COLD FRONT
WILL SHIFT THROUGH THE AREA FRIDAY NIGHT INTO SATURDAY...THEN STALL
SOUTH OF THE REGION ON SUNDAY BEFORE LIFTING BACK NORTH THROUGH THE
AREA AS A WARM FRONT ON MONDAY. ATLANTIC HIGH PRESSURE WILL THEN
PREVAIL THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO SIGNIFICANT CHANGES WERE MADE FOR THE SUNRISE UPDATE. A SPECIAL
WEATHER STATEMENT HAS BEEN ISSUED TO ADDRESS AREAS OF FOG IN
SOUTHEAST GEORGIA.
THE SURFACE AND UPPER AIR SYNOPTIC PATTERN IS VERY REMINISCENT OF
SUMMER WITH MEAN 500 HPA RIDING IN PLACE ACROSS THE SOUTHEAST U.S.
WITH THE AREA POSITIONED ALONG THE WESTERN FLANKS OF ATLANTIC HIGH
PRESSURE. CONVECTIVE DEBRIS CLOUDINESS EARLY THIS MORNING WILL
GIVE WAY TO INCREASING INSOLATION THROUGH THE DAY...WHICH WILL
EVENTUALLY YIELD A MODEST CUMULUS FIELD AHEAD OF THE DEVELOPING
SEA BREEZE.
THERE ARE NO APPARENT LOW-LEVEL TRIGGERS FOR CONVECTION TODAY
EXCEPT THE RESULTANT SEA BREEZE CIRCULATION...WHICH IN ITSELF
DOES NOT LOOK OVERLY STRONG...BUT CONVECTIVE OUTFLOWS ARE LIKELY
LURKING ACROSS INLAND AREAS BASED ON EARLIER REFLECTIVITY DATA.
THE 00Z MODELS ARE NOT OVERLY AGGRESSIVE WITH THE COVERAGE OF
SHOWERS/TSTMS DURING PEAK HEATING...WHICH SEEMS PLAUSIBLE WITH
WEAK DNVA NOTED IN THE WAKE OF SHORTWAVE ENERGY PASSING OFFSHORE
THIS MORNING. DESPITE WEAK SUBSIDENCE...MODIFIED RAP SOUNDINGS DO
SHOW MODEST INSTABILITY DEVELOPING THROUGH THE DAY AS TEMPERATURES
RISE WELL INTO THE 80S WITH DEWPOINTS HOLDING IN THE LOWER-MID
60S. SUSPECT ISOLATED CONVECTION WILL INITIATE EITHER ALONG THE
SEA BREEZE ITSELF OR MORE LIKELY ALONG THE LAKE BREEZE OR RESIDUAL
CONVECTIVE OUTFLOW OVER INLAND AREAS BY EARLY-MID AFTERNOON WITH
ADDITIONAL CONVECTIVE CLUSTERS DEVELOPING ALONG MESOSCALE BOUNDARY
COLLISIONS...MAINLY INLAND AHEAD OF THE SEA BREEZE. POPS OF 20-30
PERCENT WILL BE MAINTAINED FOR LAND AREAS TODAY AND WITH TIMING
AND PLACEMENT OF THE HIGHEST GRIDDED POPS BLENDED HEAVILY TOWARDS
THE LATEST 4KM NSSL WRF. HIGHS WILL WARM INTO THE MID-UPPER 80S
AWAY FROM THE BEACHES.
AN ISOLATED STRONG OR SEVERE TSTM CAN NOT BE RULED OUT WITHIN A
MODERATELY UNSTABLE ENVIRONMENT (SBCAPE 2600 J/KG...LIFTED INDEX
-6C...SHOWALTER INDEX -2C...HCAPE ~900 J/KG WITH DCAPE 1200 J/KG
PER MODIFIED KOGB RAP SOUNDING)...ESPECIALLY WHERE UPDRAFTS BECOME
ENHANCED ALONG MESOSCALE BOUNDARY COLLISIONS. WBZ HEIGHTS REMAIN
FAIRLY LOW FOR THE TIME YEAR AND 0-6KM BULK SHEAR IS FORECAST TO
REMAIN 20-25 KT...WHICH IS JUST HIGH ENOUGH TO SUPPORT SOME
LOOSELY ORGANIZED MULTICELLULAR CLUSTERS. WILL HIGHLIGHT ISOLATED
STRONG TO SEVERE TSTMS IN THE HAZARDOUS WEATHER OUTLOOK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
TONIGHT...EARLY EVENING CONVECTION WILL DISSIPATE WELL INLAND WITH
THE LOSS OF INSOLATION. WARM AND HUMID CONDITIONS WILL LINGER WITH
LOWS FALLING INTO THE LOWER-MID 60S. COULD SEE ANOTHER AROUND OF
PATCHY GROUND FOG IN SOME LOCATIONS...ESPECIALLY THAT RECEIVES
RAINFALL THIS AFTERNOON...BUT THE FOG DOES NOT LOOK SIGNIFICANT
ATTM.
THURSDAY...THE AREA WILL REMAIN ALONG THE WESTERN EDGE OF ATLANTIC
HIGH PRESSURE AND UNDER A MID LVL RIDGE OF HIGH PRESSURE EXTENDING
NORTHWARD FROM THE GULF OF MEXICO. THE BULK OF PRECIP ACTIVITY
SHOULD SHIFT SLIGHTLY MORE INLAND THAN PREVIOUS DAYS AS THE MID LVL
RIDGE EXPANDS OVER THE AREA WELL AHEAD OF A LOW PRESSURE TROUGH
DIGGING OVER THE CENTRAL UNITED STATES. THE PATTERN WILL RESULT IN
WARM TEMPS...WITH HIGHS IN THE MID TO UPPER 80S OVER MOST LOCATIONS.
TEMPS WILL REMAIN COOLER ALONG THE COAST GIVEN AN ONSHORE FLOW.
SUFFICIENT HEATING AND MOISTURE WILL SUPPORT A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS AWAY FROM THE COAST...BUT ACTIVITY WILL
LIKELY BE DRIVEN BY AN AFTERNOON SEABREEZE GIVEN THE LACK OF LARGER
SCALE FORCING. EXPECT MOST PRECIP TO DIMINISH WITHIN A FEW HOURS OF
SUNSET. OVERNIGHT LOWS SHOULD RANGE IN THE MID 60S. WE COULD SEE
SOME PATCHY FOG DEVELOP LATE WHILE WINDS ARE LIGHT/CALM AND DEWPTS
REMAIN IN THE MID 60S.
FRIDAY...ANOTHER WARM DAY IS ANTICIPATED WELL AHEAD OF COLD FRONT
THAT WILL MAKE WAY TO THE REGION LATE. EXPECT HIGH TEMPS TO WARM IN
THE MID/UPPER 80S FOR MOST LOCATIONS...EVEN AS CLOUD COVER INCREASES
FROM THE WEST. CHANCES OF SHOWERS AND/OR THUNDERSTORMS WILL BE
POSSIBLE...ESPECIALLY LATE AS MOISTURE DEEPENS AND MID LVL FORCING
BEGINS TO INCREASE ALONG AND AHEAD OF A SFC COLD FRONT MAKING WAY
INTO THE AREA FRIDAY NIGHT. AT THIS TIME...THE THREAT OF SEVERE
WEATHER REMAINS LOW GIVEN THE TIMING OF FROPA DURING THE OVERNIGHT
PERIOD. HOWEVER...THERE IS A LOW CHANCE OF A FEW STRONGER
THUNDERSTORMS GIVEN SBCAPES APPROACHING 1000-1250 J/KG AND 20-30 KT
LOW/MID LVL WIND FIELDS SHIFTING OVER THE AREA FRIDAY EVENING.
OVERNIGHT LOWS SHOULD REMAIN MILD UNTIL FROPA...IN THE MID 60S FOR
MOST LOCATIONS
SATURDAY...A COLD FRONT WILL PUSH THROUGH THE AREA EARLY WITH AT
LEAST CHANCES OF SHOWERS AND/OR THUNDERSTORMS AS FROPA OCCURS. DRYER
AND COOLER CONDITIONS WILL FOLLOW THE FRONT AS HIGH PRESSURE BUILDS
IN FROM THE NORTH. OVERALL HIGH TEMPS SHOULD PEAK NEAR 80 FOR
LOCATIONS AWAY FROM THE COAST...BUT WILL LIKELY BE ON A COOLING
TREND BY MID AFTERNOON OVER NORTHERN AREAS WHERE SFC WINDS SHIFT TO
NORTHEAST BEHIND THE FRONT. BY SATURDAY EVENING...MOST PRECIP
ACTIVITY WILL LIKELY BE FOCUSED IN SOUTHEAST GEORGIA...WHERE THE
FRONT CONTINUES A SOUTHWARD SHIFT BEFORE STALLING WELL SOUTH OF THE
AREA.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
A WEAKENED/STALLED FRONT WILL BE POSITIONED SOUTH OF THE AREA
THROUGH SUNDAY...WHILE A WEDGE OF HIGH PRESSURE BUILDS FROM THE
NORTH. TEMPS WILL BE COOLER...WITH OVERALL HIGHS IN THE MID 70S OVER
MOST LOCATIONS. A SLIGHT CHANCE TO CHANCE OF SHOWERS AND/OR
THUNDERSTORMS WILL MAINLY BE CONFINED TO LOCATIONS SOUTH OF
INTERSTATE 16 IN SOUTHEAST GEORGIA THROUGH EARLY MONDAY. CHANCES OF
SHOWERS AND THUNDERSTORMS SHOULD RETURN TO MOST AREAS ON MONDAY AS
THE STALLED FRONT LIFTS BACK NORTH AS A WARM FRONT WELL AHEAD OF A
DEEPENING LOW PRESSURE SYSTEM OVER THE CENTRAL UNITED STATES. HIGH
TEMPS SHOULD THEN RETURN INTO THE 80S THROUGH THE MIDDLE OF NEXT
WEEK AS THE AREA REMAINS SITUATED ALONG THE WESTERN EDGE OF ATLANTIC
HIGH PRESSURE AND STRONG RIDGING ALOFT.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
VFR. SHALLOW FOG AT KSAV WILL LINGER FOR ANOTHER HOUR BEFORE
LIFTING. THIS MAY PRODUCE VARYING VSBYS...BUT THE FOG LAYER LOOKS
RATHER THIN PER WEBCAMS. STILL LOOKS LIKE THE BEST CHANCES FOR
TSTMS WILL REMAIN WEST OF THE TERMINALS THIS AFTERNOON.
EXTENDED AVIATION OUTLOOK...LOW CHANCES OF FLIGHT RESTRICTIONS
THURSDAY AND FRIDAY WITH AFTERNOON SHOWERS AND/OR THUNDERSTORMS.
FLIGHT RESTRICTION CHANCES INCREASE FRIDAY NIGHT INTO SATURDAY
SATURDAY AS A COLD FRONT PASSES OVER BOTH TERMINALS.
&&
.MARINE...
THROUGH TONIGHT...SOUTHERLY WIND REGIME WILL PERSIST. WINDS WILL
GENERALLY REMAIN 10 KT OR LESS WITH SEAS 2-4 FT.
THURSDAY THROUGH MONDAY...CONDITIONS WILL REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS THROUGH LATE WEEK ALONG THE WESTERN EDGE OF ATLANTIC
HIGH PRESSURE. IN GENERAL...A SOUTHERLY WIND WILL REMAIN AT OR BELOW
15 KTS OUTSIDE DAILY SHOWERS AND/OR THUNDERSTORMS. BRIEF SURGES AND
SLIGHT CHANGES IN WIND DIRECTION SHOULD OCCUR NEAR AFTERNOON
SEABREEZE CIRCULATIONS. SEAS WILL BE NO HIGHER THAN 4 FT. WINDS/SEAS
SHOULD THEN INCREASE/BUILD THIS WEEKEND AS A COLD FRONT APPROACHES
FROM THE NORTHWEST FRIDAY...THEN SHIFTS OVER THE COASTAL WATERS
FRIDAY NIGHT INTO EARLY SATURDAY. HOWEVER...CONDITIONS ARE EXPECTED
TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS OUTSIDE THUNDERSTORM
ACTIVITY. A FEW THUNDERSTORMS COULD BE STRONG DURING FROPA FRIDAY
NIGHT. WINDS WILL SHIFT TO NORTH/NORTHEAST BEHIND THE FRONT AS IT
STALLS SOUTH OF THE COASTAL WATERS SATURDAY NIGHT AND SUNDAY. THE
STALLED FRONT IS THEN EXPECTED TO LIFT BACK NORTH AS A WARM FRONT ON
MONDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/DPB
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1034 AM CDT Wed Apr 8 2015
.UPDATE...
ISSUED AT 1034 AM CDT WED APR 8 2015
Have made some adjustments to PoPs and Wx based on position of
boundaries from earlier convection and the anticipated evolution
of incoming wave. High temperature forecasts remain reasonable.
Elevated boundary over southeast forecast area continues to
produce isolated thunderstorms as it sags south. Next system is
moving through Missouri this morning. Leading edge is weakening as
it moves into more stable air in wake of morning convection and
fog. This trend should change as temps rise well into the 70s and
dew pts reach well into 60s over much of the southern two-thirds
of CWA. Lastest HRRR suggests that best chances for afternoon storms
should remain south of I-72.
&&
.SHORT TERM...(Today)
ISSUED AT 255 AM CDT WED APR 8 2015
Latest surface analysis indicates the frontal boundary that was
holding stationary over south central Illinois has shifted further
north early this morning as a weak wave of low pressure was
approaching west central Illinois. Scattered convection has been
occurring north of the boundary over parts of east central Iowa
east into our far northern counties with some nickel hail reported
over the past hour around Lacon in Marshall county. We expect the
scattered convection to continue into the morning hours as the wave
rides east along the boundary. As the surface low shifts to our east
later this morning, there may actually be a southward push to the
front which is going to cause some significant problems with respect
to the afternoon temperatures, especially along and north of I-74.
The latest HRRR does indicate another weak wave forming to our west
along the boundary early this afternoon with another complex of
storms approaching west central IL. Not sure if this particular
complex of storms will ride along the boundary into central Illinois
or dive more southeast into the higher instability air mass south
of the front. POPs will increase again this afternoon in response to
this secondary wave approaching from the west. Severe potential
increases this afternoon thru this evening as the boundary gets
a push northward as the more significant shortwave pushes into the
Plains. With the warm front expected to edge across the area this
afternoon and evening, damaging wind gusts, large hail and isolated
tornadoes will all be possible. The tornado threat looks tied more
into areas along and just north of the warm front later this
afternoon and evening. Coolest temps north of I-74 where more of an
easterly flow will prevail, while south of the boundary, a blend of
the MET/MAV guid seems reasonable at this point.
&&
.LONG TERM...(Tonight through Tuesday)
ISSUED AT 255 AM CDT WED APR 8 2015
Severe weather threat through Thursday evening continues to dominate
the first part of the forecast. Current upper low moving into
northwest Nevada will open up but remain a fairly sharp wave as it
traverses the Plains on Thursday. This will help develop a surface
low over western Kansas this evening, which will surge northeast and
shove the frontal boundary back northward tonight. The trailing cold
front will sweep from west to east across the state Thursday evening
as a result.
Convection to our southwest expected to expand northeastward into
the mid-Mississippi Valley this evening. Latest SPC Day1 outlook
extended the slight risk across the entire CWA, with an enhanced
risk of severe storms from basically Springfield-Peoria westward.
This enhanced risk covers the entire area on Thursday, with
high-resolution models focusing on the mid-afternoon through early
evening time frame as the best potential in our area.
Short period of cooler and drier weather on tap for the first part
of the weekend, as high pressure drifts across the Midwest. However,
longer range models showing extended periods of rain chances early
next week. The GFS and ECMWF have a sizable range on the position
of a frontal boundary that will be setting up Sunday night and
Monday, both starting off roughly along I-70 but the GFS shows a
much stronger surge to the north by Tuesday. However, with both
favoring some sort of precip, have kept healthy rain chances in the
forecast for early next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
ISSUED AT 615 AM CDT WED APR 8 2015
Frontal boundary located over the northern portion of the forecast
area this morning will be the focus for periods of showers and
thunderstorms along with LIFR cigs and vsbys with some of the
heavy thunderstorms. Outside of the convection, and south of
the frontal boundary, we will see a period of VFR cigs today
with the main band of convection moving in after 21z but scattered
in nature, so will continue to handle with VCTS until we see how
the storms develop to our west later today.
Surface winds will be quite variable in direction and speed in
and near the thunderstorms today. Most of our area will see
southeast winds at 10 to 15 kts today into tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barker
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
650 AM CDT WED APR 8 2015
.SHORT TERM...
347 AM CDT
THROUGH THURSDAY...
TODAY THROUGH FRIDAY NIGHT...
MAIN FOCUS IS ON PERIODS OF CONVECTION...PARTICULARLY THIS
MORNING ACROSS PART OF THE FORECAST AREAS...AND ACROSS THE ENTIRE
AREA TONIGHT INTO THURSDAY. SEVERE WEATHER THREAT REMAINS OF GREAT
CONCERN THURSDAY AFTERNOON AND EVENING.
EARLY MORNING SURFACE ANALYSIS DEPICTS LOW PRESSURE OVER
NORTHEASTERN MISSOURI...WITH AN INVERTED TROUGH EXTENDING
NORTHEAST ACROSS SOUTHEAST WI/LAKE MICHIGAN. THESE FEATURES APPEAR
TO BE ASSOCIATED WITH A COUPLE OF MID-LEVEL SHORT WAVE TROUGHS
PROPAGATING ACROSS THE REGION IN BROAD WEST-SOUTHWESTERLY FLOW
ALOFT. A CLUSTER OF THUNDERSTORMS HAD DEVELOPED ACROSS SOUTHEAST
IOWA LAST EVENING IN LOW LEVEL WARM/MOIST ADVECTION MAXIMA
NORTHEAST OF THE SURFACE LOW...AND CONTINUE TO PERSIST AND EXPAND
SLOWLY EASTWARD ACROSS PARTS OF ILLINOIS EARLY THIS MORNING ON 30
KT 925 MB JET AHEAD OF SHORT WAVE. THESE STORMS ARE LIKELY TO
CONTINUE TO DEVELOP EASTWARD ACROSS MAINLY THE SOUTHERN TWO THIRDS
OR SO OF THE CWA EARLY THIS MORNING AS THE SURFACE WAVE MOVE
THROUGH THE AREA. SPC MESOANALYSIS DATA INDICATES UPSTREAM AIR
MASS CHARACTERIZED BY STEEP MID-LEVEL LAPSE RATES IN EXCESS OF 7.5
C/KM YIELDING 1000-1500 J/KG OF ELEVATED MUCAPE...AND ROUGHLY
40-45 KT OF EFFECTIVE DEEP LAYER BULK SHEAR. SOME OF THE STRONGER
CORES MAY BE CAPABLE OF PRODUCING SOME MARGINAL HAIL THIS
MORNING...THOUGH AN OVERALL WEAKENING TREND IS EXPECTED AS THE LOW
LEVEL FLOW VEERS MORE WESTERLY AND DECREASES AND REDUCES LOW LEVEL
MOISTURE TRANSPORT/THETA-E ADVECTION ACROSS OUR SOUTH AND
SOUTHEAST COUNTIES. THIS TREND IS SUPPORTED BY HIGH-RES HRRR/RAP
GUIDANCE WHICH INDICATE ACTIVITY MOVING ACROSS THE AREA THROUGH
13-14Z.
MOIST/SATURATED LOW LEVEL AIR MASS HAS ALSO REDUCED VISIBILITY IN
FOG OVER THE PAST SEVERAL HOURS...WITH SOME PATCHES OF DENSE FOG
NOTED. MAY HAVE TO CONSIDER A HEADLINE...THOUGH MORNING SHOWERS
MAY HELP RAISE VISIBILITY SOMEWHAT AND WILL CONTINUE TO MONITOR.
NOT MUCH IS EXPECTED IN THE WAY OF ORGANIZED PRECIP FROM MID-
MORNING INTO THIS AFTERNOON...WITH PASSAGE OF THE SHORT WAVE AND
WEAKENING OF THE SURFACE WAVE ALONG THE FRONT TO OUR SOUTH. WEAK
BUT PERSISTENT SOUTHWEST FLOW WILL CONTINUE ABOVE THE SHALLOW COOL
BOUNDARY LAYER NORTH OF THE SURFACE FRONT...WHICH COULD PRODUCE
SOME LIGHT SHOWERS OR DRIZZLE AT ABOUT ANY TIME...BUT IT APPEARS
THAT THE NEXT ORGANIZED ROUND OF PRECIPITATION WILL HOLD OFF UNTIL
LATER THIS AFTERNOON AND MORE SO THIS EVENING AS ANOTHER SHORT
WAVE EJECTS AHEAD OF ADVANCING WEST COAST UPPER TROUGH.
THUNDERSTORMS CHANCES INCREASE MARKEDLY THIS EVENING AS THIS NEXT
WAVE APPROACHES THIS EVENING. SOME OF THESE ELEVATED STORMS
TONIGHT MAY ALSO HAVE THE CAPABILITY OF PRODUCING LARGE HAIL WITH
STEEP LAPSE RATES AND STRONG DEEP SHEAR.
SHOWERS AND THUNDERSTORMS WILL VERY LIKELY BE ONGOING ACROSS THE
FORECAST AREA EARLY THURSDAY MORNING...AND THE EFFECT OF THE
RESULTING COLD POOL AND CLOUDINESS WILL LIKELY COMPLICATE THE
EVOLUTION OF AFTERNOON POTENTIALLY SEVERE CONVECTION ACROSS THE
AREA. NONETHELESS...A STRONG AND VERY DYNAMIC SHORT WAVE WILL
EMANATE FROM THE CURRENT WEST COAST TROUGH RESULTING IN A
DEEPENING SURFACE LOW LIFTING NORTHEAST INTO FAR NORTHERN ILLINOIS
OR SOUTHERN WISCONSIN BY THURSDAY EVENING. THE COMBINATION OF THE
APPROACHING VIGOROUS SHORT WAVE AND DEEPENING SURFACE LOW WILL
LIFT THE CURRENT STATIONARY FRONT NORTHWARD ACROSS THE FORECAST
AREA AS A WARM FRONT...WITH THE WARM SECTOR SOUTH OF THE FRONT
EXPECTED TO BECOME MODERATELY UNSTABLE DURING THE AFTERNOON AS
MLCAPES INCREASE TO 1500-2500 J/KG. STRONG WEST-SOUTHWEST FLOW
ALOFT AND BACKED SOUTHERLY WINDS IN LOW LEVELS AHEAD OF THE LOW
WILL SUPPLY COPIOUS SHEAR... SUPPORTIVE OF ORGANIZED SEVERE
THUNDERSTORMS DEVELOPING DURING THE AFTERNOON AND EARLY EVENING
HOURS AHEAD OF THE COLD FRONT WHICH WILL PUSH ACROSS THE CWA BY
MIDNIGHT. SPC HAS MAINTAINED A LARGE ENHANCED SEVERE RISK ACROSS
THE AREA FOR DAY 2/THURSDAY...WITH SOME UNCERTAINTY REMAINING
PRIMARILY TO THE EFFECT OF MORNING CONVECTION ON MESOSCALE SURFACE
FEATURES BY THURSDAY AFTERNOON. IF THE DYNAMIC SYSTEM IS ABLE TO
OVERCOME STABILIZING INFLUENCE OF EARLIER STORMS...AND IT LIKELY
WILL TO SOME DEGREE...THEN A SIGNIFICANT RISK OF DAMAGING
WIND...LARGE HAIL AND TORNADOES WILL EXIST.
WITH THE SURFACE LOW PASSING NEAR/NORTH OF THE AREA THURSDAY
NIGHT...THE COLD FRONT WILL SWEEP EAST DURING THE EVENING AND
BRING AN END TO THE SEVERE THREAT AS DRIER/COOLER AIR SPREADS IN.
A STRONG NORTHERN STREAM SHORT WAVE IS PROGGED TO DIG ACROSS THE
UPPER MIDWEST BEHIND THE FIRST SYSTEM ON FRIDAY...THOUGH DRY
AIRMASS AND CAPPING INVERSION IN 700-600 MB LAYER NOTED IN
FORECAST SOUNDINGS SHOULD PRECLUDE PRECIP IN ANY ORGANIZED
FASHION.
TEMPS...SHARP CONTRAST CONTINUES TODAY-TONIGHT WITH EAST-
NORTHEAST FLOW NORTH OF THE STATIONARY FRONT AND MOIST/CLOUDY LOW
LEVEL AIR MASS. MAY VERY WELL SEE HIGHS TODAY RANGING FROM THE
MID-40S IN FAR NORTHEAST IL TO THE LOWER 70S ALONG THE LOT/ILX
BORDER. WITH FRONT LIFTING NORTH THURSDAY MUCH OF THE AREA MAY BE
IN THE 70S...THOUGH AGAIN MORNING CONVECTION AND RESIDUAL OUTFLOW
OR CLOUDS COULD AFFECT MAX TEMPS. COOLER BUT NEAR NORMAL FRIDAY
BEHIND THE COLD FRONT...BUT STILL 55-60.
RATZER
&&
.LONG TERM...
142 AM CDT
SATURDAY THROUGH TUESDAY...
THE FIRST FEW PERIODS OF THE EXTENDED LOOK TO BE RELATIVELY
BENIGN FOR THE GREAT LAKES REGION...WITH ENSEMBLES DEMONSTRATING
MINIMAL SPREAD IN THE 500MB WAVE PATTERN. WEAK TROUGHING WILL BE
PIVOTING EAST ACROSS THE MID-ATLANTIC REGION SAT...WITH DIFFLUENT
FLOW ARRIVING FOR THE WESTERN GREAT LAKES SAT. THE PATTERN QUICKLY
FLATTENS SUN...WITH PRECIP CHANCES RETURNING FOR THE SECOND HALF
OF THE WEEKEND INTO EARLY NEXT WEEK.
ENSEMBLES BEGIN TO POINT TOWARDS A TROUGH TRYING TO DIG INTO THE
WESTERN CONUS MON...WHICH COULD SUPPORT A SHORTWAVE DEVELOPING ALONG
THE LEE-SIDE OF THE ROCKIES. WITH THE WESTERN GULF OF MEXICO
OPEN...MOISTURE SHOULD EASILY LIFT NORTH TOWARDS THE OZARKS INTO IL
LATE MON INTO TUE. AS A RESULT INSTABILITY WILL LIKELY INCREASE...SO
WILL CONTINUE TO MENTION THUNDER MON/TUE OF NEXT WEEK.
WITH THE RELATIVELY ACTIVE FLOW...THE EXTENDED TEMPS MAY END UP
SLIGHTLY ABOVE SEASONAL OR MAINLY IN THE LOW/MID 60S. PRIOR TO THE
SHORTWAVE ARRIVAL MON...TEMPS MAY PUSH INTO THE UPR 60S OR NEAR 70.
OVERNIGHT LOWS WILL ALSO REMAIN MILD.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* LIFR CIGS/VIS IMPROVING TO IFR THIS AFTERNOON.
* SCATTERED THUNDERSTORMS DEVELOPING THIS EVENING AND CONTINUING
OVERNIGHT.
* LIFR VIS/CIGS POSSIBLE TONIGHT...IMPROVING THURSDAY MORNING.
//DISCUSSION...UPDATED 12Z...
CIGS/VIS SHOULD SLOWLY IMPROVE THIS MORNING WITH IFR CIGS LIKELY
BY THIS AFTERNOON WITH VIS IMPROVING POSSIBLY TO MVFR. CIGS/VIS
COULD POSSIBLY LOWER BACK TO LIFR THIS EVENING INTO EARLY
OVERNIGHT BUT CONFIDENCE IS LOW.
COMPLEX OF THUNDERSTORMS ACROSS EASTERN IL INTO NORTH CENTRAL
INDIANA WILL CONTINUE TO MOVE EAST/SOUTHEAST AND AWAY FROM THE
AREA THIS MORNING. SOME DRIZZLE THIS MORNING AND PERHAPS A BRIEF
SHOWER BUT THE DAYLIGHT HOURS APPEAR DRY FOR THE TERMINALS. FOCUS
SHIFTS TO COMPLEX OF THUNDERSTORMS OVER NORTHEAST MO...WHICH WILL
LIKELY MOVE EAST/NORTHEAST AND INTO PARTS OF WEST CENTRAL IL MID/
LATE AFTERNOON. ADDITIONAL THUNDERSTORMS ARE EXPECTED TO DEVELOP
ACROSS NORTHERN IL THIS EVENING AND CONTINUE INTO THE OVERNIGHT
HOURS. CONFIDENCE REGARDING TIMING/LOCATION/COVERAGE IS STILL LOW
ENOUGH THAT OPTED TO CONTINUE WITH A LONGER DURATION OF VICINITY
THUNDER.
GENERALLY EASTERLY WINDS WILL CONTINUE THRU THIS EVENING WITH
SPEEDS LIKELY AT OR ABOVE 10 KTS. WINDS WILL BEGIN TO TURN
SOUTHEAST LATER THIS EVENING AND OVERNIGHT...THEN MORE SOUTH/
SOUTHWEST THURSDAY MORNING AS A WARM FRONT LIFTS THROUGH THE
TERMINALS. WHEN THIS OCCURS...EXPECT RAPID IMPROVEMENT THROUGH
MVFR CIGS AND LIKELY TO PREVAILING VFR CIGS...OUTSIDE PRECIP...
INTO THURSDAY MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM FOR CIGS/VIS THRU THE PERIOD.
* MEDIUM FOR WINDS THRU PERIOD.
* MEDIUM FOR THUNDERSTORMS TONIGHT...LOW FOR TIMING/COVERAGE. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
* THURSDAY NIGHT...STRONG TSRA IN THE EVENING. MVFR POSSIBLE.
STRONG/GUSTY SOUTHWEST WINDS BECOMING WEST.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...SLIGHT CHANCE OF SHRA. SOUTH WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. SOUTHWEST WINDS.
* TUESDAY...CHANCE OF SHRA. SOUTHWEST WINDS.
&&
.MARINE...
415 AM...A FRONTAL BOUNDARY WILL REMAIN STATIONARY JUST SOUTH OF
LAKE MICHIGAN INTO THIS EVENING...THEN BEGIN TO LIFT NORTH ACROSS
THE LAKE LATE TONIGHT AND THURSDAY AS A WARM FRONT AS LOW PRESSURE
OVER THE PLAINS MOVES NORTHEAST TONIGHT AND THURSDAY...REACHING
NORTHERN LAKE MICHIGAN BY FRIDAY MORNING. NORTHEAST WINDS WILL
REMAIN IN THE 20-25KT RANGE TODAY...WITH SOME HIGHER GUSTS
POSSIBLE. WINDS WILL SLOWLY DIMINISH LATE TONIGHT INTO THURSDAY
MORNING...THEN AS WINDS SHIFTING SOUTHWESTERLY THURSDAY AFTERNOON
AND ESPECIALLY THURSDAY EVENING...THEY WILL INCREASE TO 30 KT...
SHIFTING WESTERLY THURSDAY NIGHT AFTER A COLD FRONT MOVES ACROSS
THE LAKE. WINDS WILL SLOWLY DIMINISH FRIDAY AFTERNOON INTO FRIDAY
EVENING...THEN BECOME LIGHT SATURDAY AS HIGH PRESSURE MOVES ACROSS
THE REGION. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN
UNTIL 5 AM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
631 AM CDT Wed Apr 8 2015
.SHORT TERM...(Today)
ISSUED AT 255 AM CDT WED APR 8 2015
Latest surface analysis indicates the frontal boundary that was
holding stationary over south central Illinois has shifted further
north early this morning as a weak wave of low pressure was
approaching west central Illinois. Scattered convection has been
occurring north of the boundary over parts of east central Iowa
east into our far northern counties with some nickel hail reported
over the past hour around Lacon in Marshall county. We expect the
scattered convection to continue into the morning hours as the wave
rides east along the boundary. As the surface low shifts to our east
later this morning, there may actually be a southward push to the
front which is going to cause some significant problems with respect
to the afternoon temperatures, especially along and north of I-74.
The latest HRRR does indicate another weak wave forming to our west
along the boundary early this afternoon with another complex of
storms approaching west central IL. Not sure if this particular
complex of storms will ride along the boundary into central Illinois
or dive more southeast into the higher instability air mass south
of the front. POPs will increase again this afternoon in response to
this secondary wave approaching from the west. Severe potential
increases this afternoon thru this evening as the boundary gets
a push northward as the more significant shortwave pushes into the
Plains. With the warm front expected to edge across the area this
afternoon and evening, damaging wind gusts, large hail and isolated
tornadoes will all be possible. The tornado threat looks tied more
into areas along and just north of the warm front later this
afternoon and evening. Coolest temps north of I-74 where more of an
easterly flow will prevail, while south of the boundary, a blend of
the MET/MAV guid seems reasonable at this point.
&&
.LONG TERM...(Tonight through Tuesday)
ISSUED AT 255 AM CDT WED APR 8 2015
Severe weather threat through Thursday evening continues to dominate
the first part of the forecast. Current upper low moving into
northwest Nevada will open up but remain a fairly sharp wave as it
traverses the Plains on Thursday. This will help develop a surface
low over western Kansas this evening, which will surge northeast and
shove the frontal boundary back northward tonight. The trailing cold
front will sweep from west to east across the state Thursday evening
as a result.
Convection to our southwest expected to expand northeastward into
the mid-Mississippi Valley this evening. Latest SPC Day1 outlook
extended the slight risk across the entire CWA, with an enhanced
risk of severe storms from basically Springfield-Peoria westward.
This enhanced risk covers the entire area on Thursday, with
high-resolution models focusing on the mid-afternoon through early
evening time frame as the best potential in our area.
Short period of cooler and drier weather on tap for the first part
of the weekend, as high pressure drifts across the Midwest. However,
longer range models showing extended periods of rain chances early
next week. The GFS and ECMWF have a sizable range on the position
of a frontal boundary that will be setting up Sunday night and
Monday, both starting off roughly along I-70 but the GFS shows a
much stronger surge to the north by Tuesday. However, with both
favoring some sort of precip, have kept healthy rain chances in the
forecast for early next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
ISSUED AT 615 AM CDT WED APR 8 2015
Frontal boundary located over the northern portion of the forecast
area this morning will be the focus for periods of showers and
thunderstorms along with LIFR cigs and vsbys with some of the
heavy thunderstorms. Outside of the convection, and south of
the frontal boundary, we will see a period of VFR cigs today
with the main band of convection moving in after 21z but scattered
in nature, so will continue to handle with VCTS until we see how
the storms develop to our west later today.
Surface winds will be quite variable in direction and speed in
and near the thunderstorms today. Most of our area will see
southeast winds at 10 to 15 kts today into tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1029 AM EDT WED APR 8 2015
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 304 AM EDT WED APR 8 2015
A FRONTAL SYSTEM IS EXPECTED TO REMAIN ACROSS THE AREA THROUGH
TONIGHT...BEFORE LIFTING OFF TO THE NORTH ON THURSDAY. A COLD FRONT
IS EXPECTED TO MOVE THROUGH THE AREA THURSDAY NIGHT. IN THE WAKE OF
THIS FRONT...HIGH PRESSURE WILL MOVE INTO THE AREA OVER THE WEEKEND.
ANOTHER FRONTAL SYSTEM MAY AFFECT THE AREA BY EARLY NEXT WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 1028 AM EDT WED APR 8 2015
THERE SHOULD BE A BREAK IN THE ACTION THANKS TO STABILIZATION FROM
THIS MORNINGS SYSTEM. HOWEVER THE HRRR REINTRODUCES PRECIPITATION
DURING THE AFTERNOON AS A WARM HUMID FLOW CONTINUES FROM THE
SOUTHWEST. ALSO...BASED ON WHAT WE SEE IN ILLINOIS THERE MAY WELL
BE SOME BREAKS EARLY IN THE AFTERNOON WHICH WOULD LEAD TO RAPID
DESTABILIZATION.
ALL THINGS CONSIDERED...LIKELY POPS SEEM BEST OVER THE SOUTHERN CWA
MOST OF THE AFTERNOON AND OVER THE ENTIRE CWA BY LATER AFTERNOON.
FORECAST TEMPERATURES FOR TODAY MIGHT BE TOO HIGH. HOWEVER WITH EVEN
A FEW BREAKS THE THERMOMETER WILL ROCKET UP. HIGHS FROM THE EARLIER
FORECAST WILL BE KEPT IN THE UPDATE.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
ISSUED AT 304 AM EDT WED APR 8 2015
SURFACE WAVE EXPECTED TO MOVE ACROSS NORTHERN INDIANA
TONIGHT...WHICH MAY ALLOW FOR THE FRONT TO SAG BACK TO THE SOUTH
TEMPORARILY. MODELS SUGGEST A STRONGER LOW LEVEL JET...ON THE ORDER
OF AROUND 40 KTS...WILL BE NOSING TOWARDS WESTERN INDIANA LATE
TONIGHT. AS A RESULT...THINK THE POTENTIAL FOR CONVECTION WILL BE
HIGHER TONIGHT. WILL GO WITH HIGH POPS OVER THE NORTHERN AND
CENTRAL ZONES...TAPERING OFF TO CHANCE POPS OVER THE SOUTH. LAPSE
RATES AND DEEP LAYER SHEAR SUGGEST POTENTIAL FOR ORGANIZED SEVERE
STORMS TONIGHT.
WILL CONTINUE WITH HIGH POPS ON THURSDAY AND THURSDAY NIGHT AS
PROGGED LOW LEVEL JET OF 45-50 KTS INTERACTS WITH AN APPROACHING
UPPER TROUGH AND SURFACE COLD FRONT. MAY BE A LULL IN THE
PRECIPITATION THREAT THURSDAY AFTERNOON AS THE LOCAL AREA GETS
FURTHER INTO THE WARM SECTOR BEFORE COLD FRONT ARRIVES THURSDAY
EVENING...BUT WON/T GET TOO DETAILED IN THE TIMING AT THIS POINT.
APPEARS DEEP SHEAR WILL BE MAXIMIZED OVER THE AREA THURSDAY NIGHT AS
THE CORE OF THE MID LEVEL JET APPROACHES. POTENTIAL FOR SEVERE
WILL CONTINUE UNTIL FRONTAL PASSAGE LATE THURSDAY NIGHT.
FRONTAL SHOULD BE FAR ENOUGH OFF TO THE EAST BY FRIDAY MORNING TO GO
DRY FOR FRIDAY AND FRIDAY NIGHT.
LOW LEVEL THICKNESS PROGS SUGGEST THE GFS MOS TEMPERATURE GUIDANCE
IN THE LATER PERIODS LOOK REASONABLE AT THIS POINT...ALTHOUGH THE
LOWS FRIDAY MORNING LOOK TOO WARM IN THE WAKE OF THE COLD FRONT.
WILL LOWER THEM ABOUT 3-5 DEGREES IN THAT PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
ISSUED AT 304 AM EDT WED APR 8 2015
DRY PLEASANT WEATHER EXPECTED FOR MUCH OF THE WEEKEND AS HIGH
PRESSURE MOVES THROUGH THE OHIO VALLEY. AN UPPER TROUGH WILL BE IN
THE PROCESS OF MOVING AWAY TO THE EAST ON SATURDAY...WITH RIDGING
ALOFT AND WARM ADVECTION DEVELOPING FOR THE SECOND HALF OF THE
WEEKEND. HIGHS IN THE UPPER 50S AND LOWER 60S SATURDAY WILL WARM
PRIMARILY INTO THE 60S FOR SUNDAY.
UNSETTLED WEATHER THEN RETURNS FOR MUCH OF THE REST OF THE EXTENDED.
BROAD UPPER TROUGH EXPANDING ACROSS THE PACIFIC NORTHWEST AND
NORTHERN PLAINS WILL SERVE TO FLATTEN THE RIDGE BY LATE WEEKEND WITH
MOISTURE INCREASING AS A WEAK FRONT MOVES INTO THE GREAT LAKES.
COULD SEE A FEW SHOWERS BY SUNDAY AFTERNOON OVER WESTERN COUNTIES
WITH MORE EXTENSIVE PRECIP COVERAGE SUNDAY NIGHT AS THE SYSTEM TAPS
INTO A GULF MOISTURE FETCH. FAST MOVING UPPER LOW TRACKING WITH THE
SUBTROPICAL JET WILL MOVE FROM BAJA CALIFORNIA EARLY SUNDAY INTO THE
SOUTHERN PLAINS BY LATE MONDAY WITH SURFACE CYCLOGENESIS BY MONDAY
NIGHT. WARM FRONT SETS UP INTO THE OHIO VALLEY LATE MONDAY THROUGH
TUESDAY AND WILL PROMOTE ANOTHER PERIOD WITH SHOWERS AND
THUNDERSTORMS AS THE SURFACE WAVE TRACKS INTO THE REGION BY EARLY
WEDNESDAY. WILL CARRY CHANCE POPS FROM SUNDAY NIGHT INTO MIDWEEK.
HIGHS WILL LARGELY REMAIN IN THE 60S FOR MONDAY AND TUESDAY AS
CLOUDS AND RAINFALL LIKELY TO LIMIT TEMP RISES.
&&
.AVIATION /UPDATE FOR 081200Z TAFS/...
ISSUED AT 956 AM EDT WED APR 8 2015
FIRST THUNDERSTORM COMPLEX EXITING TAF SITES AT 081400Z AFTER
PRODUCING A LOT OF QUARTER INCH TO HALF INCH DIAMETER HAIL AND
ISOLATED 40 KNOT WIND GUSTS. TORRENTIAL RAINS ALSO DROPPED
VISIBILITIES TO AROUND ONE MILE BRIEFLY.
WINDS SWITCHED TO NORTHWEST WITH SQUALL LINE PASSAGE AND ARE
CURRENTLY WORKING THERE WAY AROUND THE DIAL FROM EAST TO SOUTHEAST
AND EVENTUALLY TO SOUTH AND SOUTHWEST BY 081700Z AND BECOMING GUSTY.
CLOUD DECKS BRIEFLY DROPPED BELOW 2000 FEET AT CORE OF STORMS BUT
HAVE RECOVERED TO BASES OVER 3000 FEET.
FORECASTS WILL BE ADJUSTED TO VFR VSBY AND CLOUD DECKS WHILE WINDS
WORK THERE WAY BACK TO SOUTH. THE FEW CELLS REFORMING IN EASTERN
ILLINOIS DO NOT APPEAR TO GROW IN COVERAGE BUT WILL BE THREAT TO
TERRE HAUTE THROUGH 081600Z.
MISSOURI THUNDERSTORM COMPLEX LIKELY TO BECOME A PLAYER FOR
CENTRAL INDIANA TAF SITES LATE THIS AFTERNOON AND EVENING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JAS
NEAR TERM...JK
SHORT TERM...JAS
LONG TERM....RYAN
AVIATION...TUCEK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1011 AM EDT WED APR 8 2015
.SYNOPSIS...
ISSUED AT 1003 AM EDT WED APR 8 2015
SEVERAL PERIODS OF RAIN WILL BE POSSIBLE DURING THE NEXT COUPLE
OF DAYS. A STATIONARY FRONT OVER CENTRAL PORTIONS OF INDIANA AND
OHIO IS EXPECTED TO LIFT SLOWLY NORTH INTO MICHIGAN TONIGHT.
SCATTERED THUNDERSTORMS ARE POSSIBLE NEAR THE FRONT TODAY WITH
SHOWERS AND THUNDERSTORMS LIKELY BECOMING NUMEROUS TONIGHT. A COLD
FRONT WILL APPROACH THE AREA ON THURSDAY LIKELY CAUSING ANOTHER
ROUND OF THUNDERSTORMS. HIGHS TODAY ARE EXPECTED TO RANGE FROM
THE MID 50S NORTH OF THE FRONT IN SOUTHERN MICHIGAN TO THE LOW 70S
SOUTH OF THE FRONT SOUTH OF US 30. LOWS TONIGHT WILL BE IN THE
50S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT WED APR 8 2015
THE CLOUDY...COOL PATTERN CONTINUES AS WE MAINTAIN OUR POSITION
NORTH OF THE STATIONARY FRONT. A WEAK SHORTWAVE HAS TRIGGERED SOME
CONVECTION IN SE IOWA/ WESTERN ILLINOIS JUST NORTH OF THIS
STATIONARY FRONT. THE STORMS SEEM TO BE STRUGGLING WITH EASTWARD
EXTENT...LIKELY DUE TO A SLIGHTLY STRONGER CAP AT 650MB AND LESS
INFLUENCE FROM THE MID LEVEL WAVE. GIVEN THE REMAINING UNCERTAINTY
WITH THE EVOLUTION OF THIS CONVECTIVE COMPLEX AS IT MOVES
EASTWARD...HAVE KEPT POPS IN THE HIGH CHANCE RANGE.
EXPECT A LULL IN THE PRECIPITATION DURING THE AFTERNOON ON TODAY
AS WEAK SHORTWAVE RIDGING BUILDS IN AHEAD OF THE NEXT SHORTWAVE TO
EJECT OUT OF THE CENTRAL PLAINS. THIS WILL ALSO ALLOW FOR A LONG
AWAITED SHIFT NORTHWARD IN THE FRONTAL BOUNDARY. THIS PSEUDO WARM
FRONTAL SURGE WILL CREATE SIGNIFICANT BUST POTENTIAL FOR HIGH
TEMPERATURES ON TODAY. AREAS SOUTH OF THE SURFACE FRONT WILL
LIKELY WARM INTO THE LOW 70S WITH AREAS NORTH OF THE FRONT REMAINING
IN THE MID 50S. THE EXACT PROGRESSION OF THIS FRONT NORTHWARD WILL
DICTATE EXACTLY WHO SEES THE WARMER TEMPERATURES...BUT THE LATEST
HIRES GUIDANCE PUTS THE MAX NORTHWARD PROGRESSION RIGHT ALONG US30.
REGARDLESS OF THE EXACT PLACEMENT OF THIS FRONT...ITS PRESENCE
ACROSS OUR AREA MEANS WE WILL BE FAVORABLE FOR THUNDERSTORM
DEVELOPMENT DURING THE EVENING AND INTO THE OVERNIGHT HOURS. THERE
IS SIGNIFICANT UNCERTAINTY WRT TIMING OF STORMS ACROSS THE AREA. NAM
AND RAP HAVE A DECENT SHORTWAVE SPAWNING STORMS NORTH OF SAINT LOUIS
DURING THE AFTERNOON AND MOVING THAT MCS THROUGH OUR AREA AROUND
00Z. ONLY GLOBAL GUIDANCE WHICH EVEN HINTS AT A WAVE MOVING THROUGH
AT THAT TIME IS THE GEM AND THEREFORE GLOBAL GUIDANCE HOLDS OFF ON
CONVECTION UNTIL AFTER MIDNIGHT. IR SATELLITE DOES SHOW SOME COOLER
CLOUD TOPS IN SW KANSAS WHERE THIS SW IS CURRENTLY SUPPOSED TO
BE...SO AM INCLINED TO BELIEVE THE HIRES GUIDANCE AND DISCOUNT THE
GLOBAL GUIDANCE AS LACKING THE RESOLUTION TO PROPERLY RESOLVE THIS
WAVE. SEVERE RISK DOES EXIST WITH ANY STORMS THAT DO DEVELOP IN THIS
AFTERNOON TIMEFRAME GIVEN 40 TO 50 KNOTS OF DEEP LAYER SHEAR AND
1500 TO 2000 J/KG OF SBCAPE SOUTH OF THE SURFACE FRONT. EVEN IF THE
EARLY EVENING STORM DEVELOPMENT ON THE HIRES GUIDANCE DOESN`T
MATERIALIZE...THERE WILL STILL BE AN ISOLATED RISK OF SEVERE WEATHER
DURING THE OVERNIGHT HOURS GIVEN THE ~2000 J/KG OF MUCAPE AND 30
KNOT LLJ WITH THE REMAINING PRESENCE OF 35 TO 45 KNOTS OF DEEP LAYER
SHEAR.
&&
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 419 AM EDT WED APR 8 2015
PRIMARY CONCERNS FOR THE LONG TERM WILL CENTER ON CONVECTIVE/SEVERE
POTENTIAL THURSDAY/THURSDAY NIGHT...FOLLOWED BY RENEWED PRECIP
CHANCES EARLY NEXT WEEK.
SHOWERS/STORMS WILL LIKELY BE ONGOING THURSDAY MORNING AS UPPER JET
STREAK ASSOCIATED WITH SUBTROPICAL JET ENCROACHES ON THE OHIO RIVER
VALLEY. AXIS OF 40-50 KNOT SOUTHWESTERLY LOW LEVEL FLOW NOSING INTO
THE AREA BY MIDDAY WILL ALLOW FOR APPRECIABLE LOW/MID LEVEL
MOISTURE ADVECTION. MOISTURE CONVERGENCE AT NOSE OF STRONGER LOW
LEVEL FLOW SHOULD ALLOW POCKET OF PWATS NEAR 1.5 INCHES TO TRACK
ACROSS FORECAST AREA THURSDAY MORNING WITH AMPLE ELEVATED MOISTURE
FOR SHOWERS AND EMBEDDED THUNDER. POTENTIAL OF SOME LOCALLY HEAVIER
RAINFALL AMOUNTS STILL APPEARS TO BE INTACT THROUGH THURSDAY MORNING
IN ASSOCIATION WITH THIS FORCING ALONG WITH POTENTIAL OF SOME HAIL
GIVEN ELEVATED INSTABILITY AND RELATIVELY LOW FREEZING/WBZ ZERO
HEIGHTS BETWEEN 9-10K FT.
SOME DEGREE OF UNCERTAINTY REMAINS REGARDING CONVECTIVE EVOLUTION
THURSDAY AFTERNOON AND ASSOCIATED IMPACTS ON INSTABILITY MAGNITUDES
DURING PEAK HEATING. ATTENTION FOR THURSDAY AFTERNOON/NIGHT WILL
SHIFT UPSTREAM TO MORE ROBUST EASTERN PACIFIC WAVE WHICH SHOULD
ACQUIRE NEGATIVE TILT ACROSS THE WESTERN GREAT LAKES THURSDAY
EVENING. FRONTAL CONVERGENCE AND LEADING EDGE OF MID LEVEL DRY SLOT
SHOULD REGENERATE POTENTIALLY VIGOROUS CONVECTIVE DEVELOPMENT
ACROSS ILLINOIS DURING THE AFTERNOON...POSSIBLY TRACKING INTO
WESTERN PORTIONS OF LOCAL AREA THURSDAY EVENING. EXTENT OF ANY
THINNING CLOUD COVER THURSDAY AFTERNOON/LOW LEVEL TEMP TRENDS WILL
HAVE A BIG IMPACT ON INSTABILITY MAGNITUDES. GIVEN STRENGTH OF
BACKGROUND WIND FIELDS...A WIND THREAT MAY EVOLVE THURSDAY EVENING
EVEN IF AFTERNOON INSTABILITY RECOVERY IS SOMEWHAT LIMITED. AS
MENTIONED IN PREVIOUS FORECAST...A SOMEWHAT HIGHER SEVERE THREAT MAY
UNFOLD IF GREATER LATE AFTERNOON INSTABILITY CAN BE REALIZED GIVEN
SUBSTANTIAL SHEAR PROFILES...AND IN LIGHT OF DIFFERENTIAL
MOISTURE ADVECTION IMMEDIATELY PRECEDING SFC FRONT THURSDAY NIGHT
ASSOCIATED WITH THE DRY SLOT. SPC DAY2 OUTLOOK HAS MAINTAINED HIGHER
SVR PROBS ACROSS WESTERN THIRD/HALF OF AREA...WITH POSSIBILITY OF
WEAK NEAR SFC DIURNAL COOLING LATER THURSDAY EVENING DIMINISHING
INSTABILITY MAGNITUDES A BIT ACROSS THE EAST. ONLY TWEAK TO PREVIOUS
FORECAST WAS TO SLIGHTLY SPEED UP TIMING OF WEST TO EAST POP
REDUCTION LATER THURSDAY NIGHT FOLLOWING COLD FRONT PROGRESSION.
DID MAINTAIN SLIGHT CHANCE RAIN SHOWER POPS ACROSS THE FAR NORTH/FAR
EAST EARLY FRIDAY MORNING GIVEN LINGERING MID/UPPER FORCING WITH A
SERIES OF SMALLER SCALE WAVES ROTATING THROUGH LONGWAVE TROUGH...BUT
ADDITIONAL PRECIP AMOUNTS ACROSS THESE LOCATIONS SHOULD BE QUITE
LIGHT. BREEZY/WINDY CONDITIONS CAN ALSO BE EXPECTED WITH DEEPER POST
FRONTAL MIXING LATE THURSDAY NIGHT INTO FRIDAY. IT STILL APPEARS AS
THOUGH THE FRIDAY NIGHT THROUGH SUNDAY PERIOD SHOULD BE DRY WITH
NEAR SEASONABLE TEMPS UNDER INFLUENCE OF MID/UPPER LEVEL RIDGING.
LOW LEVEL ANTICYCLONE TO DEPART TO THE EAST SUNDAY NIGHT INTO MONDAY
ALLOWING FOR A FAIRLY QUICK TRANSITION TO STRONGER LOW LEVEL
MOISTURE TRANSPORT FOR MONDAY. GOOD MOISTURE AVAILABILITY AND
APPROACH OF CUT-OFF SOUTHERN STREAM PV ANOMALY FOR TUE/WED SHOULD
KEEP CHANCES OF SHOWERS AND STORMS GOING THROUGH THE END OF THE
PERIOD AS THIS WAVE EVENTUALLY DAMPENS ACROSS THE AREA. THIS PATTERN
WILL ALSO BE CONDUCIVE FOR SHARPLY MODERATING TEMPERATURES ONCE
AGAIN FOR EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 639 AM EDT WED APR 8 2015
A SHORT WAVE ACROSS CENTRAL ILLINOIS AND ACCOMPANYING LOW LEVEL
WARM/MOIST ADVECTION HAS LED TO SUFFICIENT ELEVATED INSTABILITY
FOR SCATTERED SHOWERS AND THUNDERSTORMS. ORIENTATION OF THE LOW
LEVEL WARM FRONT WOULD SUGGEST BEST CHANCE OF THUNDER ALONG AND
SOUTH OF ROUTE 30 THROUGH AROUND 15Z. VEERING LOW LEVEL JET SHOULD
TEND TO WEAKEN LOW LEVEL MOISTURE CONVERGENCE A BIT OVER THE NEXT
HOUR OR TWO...SO STILL SOME UNCERTAINTY AS TO COVERAGE OF TS AS
FAR EAST AS KFWA BUT MAY NEED TO CARRY VCTS FOR A FEW HOURS. LIFR
CONDITIONS SHOULD GRADUALLY IMPROVE TO LOWER END MVFR FROM SOUTH
TO NORTH LATER THIS MORNING INTO EARLY AFTERNOON AS WARM FRONT
EDGES A BIT FARTHER NORTH. THE NEXT FAST MOVING SHORT WAVE
EJECTING OUT OF SOUTHWEST CONUS TONIGHT WILL ALLOW FOR RENEWED LOW
LEVEL THETAE ADVECTION AND AN INCREASING CHANCE OF SHOWERS/STORMS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...JT
SHORT TERM...BENTLEY
LONG TERM...MARSILI
AVIATION...MARSILI
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
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AREA FORECAST DISCUSSION
NWS WICHITA KS
1045 AM CDT WED APR 8 2015
.MESOSCALE DISCUSSION...
ISSUED AT 1037 AM CDT WED APR 8 2015
LOOKS LIKE THE SCENARIO MAY BE STARTING TO SHOW ITSELF. RADAR DATA
SHOWING SOME LIGHT RETURNS OVER OKLAHOMA. THIS MATCHES WELL WITH
THE HRRR/RAP RUNS...WHICH HAVE BEEN SUGGESTING TWO ROUNDS OF
STORMS.
THE MOST LIKELY SCENARIO RIGHT NOW LOOKS LIKE THE WEAK RETURNS
WILL DEVELOP INTO ELEVATED STORMS ACROSS OKLAHOMA. THESE ARE
EXPECTED TO MOVE NORTHEAST INTO SOUTH-CENTRAL KANSAS AROUND 19Z
AND MOVE THROUGH SOUTHEAST KANSAS EAST OF THE TURNPIKE. AS
STATED...THESE WILL MORE THAN LIKELY BE ELEVATED WITH A VERY LARGE
HAIL AND WIND THREAT. IF THE STORMS CAN GET SURFACE BASED...THEN
IT SEEMS THAT WE COULD GET A TORNADO...BUT THAT REMAINS UNCERTAIN.
THE SECOND ROUND OCCURS AROUND 00Z WHERE THE DRYLINE RETREATS AND
SHEAR INCREASES AS A RESULT OF THE LOW LEVEL JET AND UPPER LEVEL
DISTURBANCE COUPLING AND MOVING THROUGH. THIS IS THE SIGNIFICANT
TORNADO AREA...SOUTH-CENTRAL KANSAS.
KRC
&&
.SYNOPSIS...
ISSUED AT 332 AM CDT WED APR 8 2015
WATER VAPOR IMAGERY SHOWS A STRONG SHORTWAVE TRACKING OVER THE
CENTRAL GREAT BASIN. AT THE SURFACE...LOW PRESSURE IS SITUATED
OVER SE CO WITH THE SYNOPTIC FRONT STRETCHING FROM JUST NORTH OF
KGAG TO BETWEEN KCNU AND KPPF. MEANWHILE...A LOSE DRYLINE EXTENDS
ACROSS THE OK PANHANDLE AND INTO WEST TX.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
ELEVATED STORMS DEVELOPED A COUPLE HOURS AGO OVER THE FLINT HILLS
IN RESPONSE TO A RAPID INCREASE IN MOISTURE TRANSPORT IN THE
850-700MB LAYER. THIS ACTIVITY SHOULD FOR THE MOST PART STAY
NORTHEAST OF THE FORECAST AREA.
SIGNIFICANT SEVERE STORMS STILL LOOK LIKELY THIS AFTERNOON AND
EVENING. CURRENTLY HAVE A LEAN TO THE RAP13 DUE TO ITS PERFORMANCE
WITH THE CONVECTION THAT OCCURRED OVER THE LAST SEVERAL HOURS OVER
SE KS. IN ADDITION...IT SEEMS TO BE DOING A DECENT JOB CAPTURING
THE CURRENT ELEVATED CONVECTION. THE GFS LIFTS THE WARM FRONT
MUCH FURTHER NORTH COMPARED TO THE NAM AND RAP WITH THE FRONT
ALONG I-70. MEANWHILE THE RAP AND NAM LIFT THE FRONT TO JUST NORTH
OF KICT TO SOUTH OF KSLN.
CURRENT THINKING IS THAT THE TRIPLE POINT BY LATE AFTERNOON WILL
BE SITUATED JUST SOUTHWEST OF THE FORECAST AREA NEAR OR JUST NORTH
OF KGAG WITH THE SYNOPTIC FRONT EXTENDING TO THE NORTHEAST NEAR
KICT AND THEN TO NEAR KEMP. WATER VAPOR IMAGERY SHOWS A LEAD
IMPULSE/JET MAX OVER NORTHERN BAJA. EXPECTING STORMS TO DEVELOP
NEAR THE TRIPLE POINT AS THIS FEATURE MOVES OUT OF THE SOUTHERN
HIGH PLAINS. ADDITIONAL DEVELOPMENT CAN THEN BE EXPECTED NORTHEAST
ALONG THE SYNOPTIC FRONT. IT SEEMS WITH EACH MODEL RUN THE DEEP
LAYER SHEAR HAS INCREASED SLIGHTLY AND THE 00Z RUNS WERE NO
EXCEPTION...WITH AROUND 50KTS OF 0-6KM SHEAR AND 65-80KTS OF
0-8KM SHEAR OVER SOUTH CENTRAL KS. THESE SHEAR VALUES WILL COMBINE
WITH 2000-3000J/KG OF CAPE TO ALLOW ANY STORM THAT DEVELOPS TO
QUICKLY BECOME SEVERE. THE SCARY PART IS THAT WITH THE
RETREATING DRYLINE AFTER 00Z...THE ENVIRONMENT ACTUALLY BECOMES
MORE FAVORABLE AFTER DARK AS WINDS BACK AND THE LOW LEVEL JET GETS
GOING. SO NOT OUT OF THE QUESTION TO GET A TORNADO AFTER DARK OVER
SOUTH CENTRAL KS. THE BEST TORNADO POTENTIAL TONIGHT LOOKS TO BE
SOUTH OF HIGHWAY 50 AND WEST OF HIGHWAY 99. IF THE NAM AND RAP13
VERIFIES...SEVERE STORMS OVER CENTRAL KS WOULD BE LESS LIKELY.
BY 12Z THU...THE SHORTWAVE WILL BE TRACKING ACROSS NORTHERN
KS/NEBRASKA WITH THE SYNOPTIC FRONT CATCHING UP TO THE DRYLINE AND
SURGING EAST. WHILE THERE MAYBE SOME REMNANT STORMS OVER SE KS
AROUND SUNRISE...THE BULK OF THE ACTIVITY AFTER 15Z THU WILL BE
EAST OF THE FORECAST AREA. IT NOW LOOKS LIKE THE BETTER CHANCES
FOR PRECIP ON THE BACKSIDE OF THIS SYSTEM SHOULD STAY NORTH OF THE
FORECAST AREA THU.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
A LARGE AREA OF HIGH PRESSURE WILL ENCOMPASS THE PLAINS FOR FRI
WITH TEMPS FINALLY GETTING BACK TO SEASONAL VALUES. BOTH THE GFS
AND ECMWF BRING A SOUTHERN STREAM SYSTEM OUT OF THE BAJA REGION
AND INTO WEST TX BY SUN EVENING. WARM ADVECTION AHEAD OF THIS
SYSTEM MAY BRING SOME SCATTERED SHOWERS AND STORMS SAT BUT THE
BETTER PRECIP CHANCES LOOK TO ARRIVE SUN NIGHT AND CONTINUE
THROUGH MON WHEN THE IMPULSE LIFTS ACROSS THE PLAINS. THE GFS HAS
THIS FEATURE QUITE A BIT FURTHER WEST COMPARED TO THE ECMWF WHICH
RESULTS IN THE ECMWF BEING THE WETTER SOLUTION.
LAWSON
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1147 PM CDT TUE APR 7 2015
IFR/LIFR CIGS CONTINUE TO SPREAD SOUTH AND EAST IN THE WAKE OF THE
FRONT WHILE SEVERE STORMS LINGER ACROSS SOUTHEAST KANSAS THROUGH
THE PREDAWN HOURS. A WARM FRONT IS PROGGED TO LIFT NORTH DURING
THE DAY ON WEDNESDAY ALLOWING MVFR/VFR TO RETURN DURING THE LATE
MORNING/EARLY AFTERNOON. WINDS ARE EXPECTED TO SHIFT TO THE SOUTH
WITH SCATTERED STORMS DEVELOPING ALONG A DRY LINE AND ALONG THE
WARM FRONT LATE WED AFTERNOON/EVENING SPREADING EASTWARD ACROSS
THE AREA.
&&
.FIRE WEATHER...
ISSUED AT 332 AM CDT WED APR 8 2015
MAIN FIRE WEATHER CONCERNS LOOK TO ON THURSDAY.
EVEN WITH PLENTY OF LOW LEVEL MOISTURE...VERY HIGH FIRE DANGER
WILL BE IN PLACE OVER SOUTH CENTRAL AND SE KS DUE TO GUSTY SOUTH
WINDS. HOWEVER...THE CRITICAL FIRE WEATHER DAY LOOKS TO BE THU.
THIS IS WHEN STRONG NW WINDS WILL BE IN PLACE BY THE AFTERNOON
HOURS ALONG WITH RH`S IN THE 35-45% RANGE. WIND SPEEDS THU
AFTERNOON WILL BE IN THE 20-30 MPH RANGE WITH HIGHER GUSTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 79 56 71 38 / 30 30 10 0
HUTCHINSON 74 52 67 37 / 30 20 10 0
NEWTON 77 54 67 38 / 40 30 10 0
ELDORADO 80 60 69 40 / 40 40 10 10
WINFIELD-KWLD 82 61 72 41 / 40 30 10 0
RUSSELL 60 46 63 35 / 20 20 10 10
GREAT BEND 65 46 64 35 / 20 10 10 0
SALINA 70 50 65 35 / 30 30 20 10
MCPHERSON 72 51 66 36 / 30 30 10 10
COFFEYVILLE 82 65 76 43 / 40 40 30 10
CHANUTE 81 64 73 41 / 40 50 30 10
IOLA 80 63 72 40 / 40 50 30 10
PARSONS-KPPF 81 64 74 42 / 40 50 30 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
951 AM CDT WED APR 8 2015
.MESOSCALE DISCUSSION...
ISSUED AT 950 AM CDT WED APR 8 2015
LATEST DATA ANALYSIS SHOWS THE FRONT EXTENDING FROM NEAR KMCI-
KEMP-KVNX. IT IS SLOWLY MOVING NORTH AS OF 1430Z. 0-6KM BULK SHEAR
VALUES VIA LAPS ARE 40-50 KNOTS ALONG THE FRONT WITH 0-1KM BULK
SHEAR VALUES OF 15 TO 20 KNOTS. THIS MEANS THAT CONDITIONS REMAIN
FAVORABLE FOR TORNADIC THUNDERSTORMS THIS AFTERNOON.
LATEST RUNS OF THE HRRR...EXPERIMENTAL HRRR...AND THE RAP ARE
SUGGESTING CONVECTIVE INITIATION EARLIER...PERHAPS AS EARLY AS
19-20Z. THIS IS LIKELY FROM THE UPPER LEVEL DISTURBANCE BEING
FURTHER EAST THAN SOME OF THE PREVIOUS RUNS OF THE MODELS. MOREOVER...TRENDS
HAVE BEEN SUGGESTING STORMS SLIGHTLY FURTHER EAST...BUT WANT TO
HOLD OFF ON MAKING ANY CONCLUSIONS ON THAT UNTIL IT IS VERY CLEAR.
RIGHT NOW...THINKING THE THREAT AREA IS STILL FINE WITH INITIATION
AROUND 20Z.
KRC
&&
.SYNOPSIS...
ISSUED AT 332 AM CDT WED APR 8 2015
WATER VAPOR IMAGERY SHOWS A STRONG SHORTWAVE TRACKING OVER THE
CENTRAL GREAT BASIN. AT THE SURFACE...LOW PRESSURE IS SITUATED
OVER SE CO WITH THE SYNOPTIC FRONT STRETCHING FROM JUST NORTH OF
KGAG TO BETWEEN KCNU AND KPPF. MEANWHILE...A LOSE DRYLINE EXTENDS
ACROSS THE OK PANHANDLE AND INTO WEST TX.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
ELEVATED STORMS DEVELOPED A COUPLE HOURS AGO OVER THE FLINT HILLS
IN RESPONSE TO A RAPID INCREASE IN MOISTURE TRANSPORT IN THE
850-700MB LAYER. THIS ACTIVITY SHOULD FOR THE MOST PART STAY
NORTHEAST OF THE FORECAST AREA.
SIGNIFICANT SEVERE STORMS STILL LOOK LIKELY THIS AFTERNOON AND
EVENING. CURRENTLY HAVE A LEAN TO THE RAP13 DUE TO ITS PERFORMANCE
WITH THE CONVECTION THAT OCCURRED OVER THE LAST SEVERAL HOURS OVER
SE KS. IN ADDITION...IT SEEMS TO BE DOING A DECENT JOB CAPTURING
THE CURRENT ELEVATED CONVECTION. THE GFS LIFTS THE WARM FRONT
MUCH FURTHER NORTH COMPARED TO THE NAM AND RAP WITH THE FRONT
ALONG I-70. MEANWHILE THE RAP AND NAM LIFT THE FRONT TO JUST NORTH
OF KICT TO SOUTH OF KSLN.
CURRENT THINKING IS THAT THE TRIPLE POINT BY LATE AFTERNOON WILL
BE SITUATED JUST SOUTHWEST OF THE FORECAST AREA NEAR OR JUST NORTH
OF KGAG WITH THE SYNOPTIC FRONT EXTENDING TO THE NORTHEAST NEAR
KICT AND THEN TO NEAR KEMP. WATER VAPOR IMAGERY SHOWS A LEAD
IMPULSE/JET MAX OVER NORTHERN BAJA. EXPECTING STORMS TO DEVELOP
NEAR THE TRIPLE POINT AS THIS FEATURE MOVES OUT OF THE SOUTHERN
HIGH PLAINS. ADDITIONAL DEVELOPMENT CAN THEN BE EXPECTED NORTHEAST
ALONG THE SYNOPTIC FRONT. IT SEEMS WITH EACH MODEL RUN THE DEEP
LAYER SHEAR HAS INCREASED SLIGHTLY AND THE 00Z RUNS WERE NO
EXCEPTION...WITH AROUND 50KTS OF 0-6KM SHEAR AND 65-80KTS OF
0-8KM SHEAR OVER SOUTH CENTRAL KS. THESE SHEAR VALUES WILL COMBINE
WITH 2000-3000J/KG OF CAPE TO ALLOW ANY STORM THAT DEVELOPS TO
QUICKLY BECOME SEVERE. THE SCARY PART IS THAT WITH THE
RETREATING DRYLINE AFTER 00Z...THE ENVIRONMENT ACTUALLY BECOMES
MORE FAVORABLE AFTER DARK AS WINDS BACK AND THE LOW LEVEL JET GETS
GOING. SO NOT OUT OF THE QUESTION TO GET A TORNADO AFTER DARK OVER
SOUTH CENTRAL KS. THE BEST TORNADO POTENTIAL TONIGHT LOOKS TO BE
SOUTH OF HIGHWAY 50 AND WEST OF HIGHWAY 99. IF THE NAM AND RAP13
VERIFIES...SEVERE STORMS OVER CENTRAL KS WOULD BE LESS LIKELY.
BY 12Z THU...THE SHORTWAVE WILL BE TRACKING ACROSS NORTHERN
KS/NEBRASKA WITH THE SYNOPTIC FRONT CATCHING UP TO THE DRYLINE AND
SURGING EAST. WHILE THERE MAYBE SOME REMNANT STORMS OVER SE KS
AROUND SUNRISE...THE BULK OF THE ACTIVITY AFTER 15Z THU WILL BE
EAST OF THE FORECAST AREA. IT NOW LOOKS LIKE THE BETTER CHANCES
FOR PRECIP ON THE BACKSIDE OF THIS SYSTEM SHOULD STAY NORTH OF THE
FORECAST AREA THU.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
A LARGE AREA OF HIGH PRESSURE WILL ENCOMPASS THE PLAINS FOR FRI
WITH TEMPS FINALLY GETTING BACK TO SEASONAL VALUES. BOTH THE GFS
AND ECMWF BRING A SOUTHERN STREAM SYSTEM OUT OF THE BAJA REGION
AND INTO WEST TX BY SUN EVENING. WARM ADVECTION AHEAD OF THIS
SYSTEM MAY BRING SOME SCATTERED SHOWERS AND STORMS SAT BUT THE
BETTER PRECIP CHANCES LOOK TO ARRIVE SUN NIGHT AND CONTINUE
THROUGH MON WHEN THE IMPULSE LIFTS ACROSS THE PLAINS. THE GFS HAS
THIS FEATURE QUITE A BIT FURTHER WEST COMPARED TO THE ECMWF WHICH
RESULTS IN THE ECMWF BEING THE WETTER SOLUTION.
LAWSON
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1147 PM CDT TUE APR 7 2015
IFR/LIFR CIGS CONTINUE TO SPREAD SOUTH AND EAST IN THE WAKE OF THE
FRONT WHILE SEVERE STORMS LINGER ACROSS SOUTHEAST KANSAS THROUGH
THE PREDAWN HOURS. A WARM FRONT IS PROGGED TO LIFT NORTH DURING
THE DAY ON WEDNESDAY ALLOWING MVFR/VFR TO RETURN DURING THE LATE
MORNING/EARLY AFTERNOON. WINDS ARE EXPECTED TO SHIFT TO THE SOUTH
WITH SCATTERED STORMS DEVELOPING ALONG A DRY LINE AND ALONG THE
WARM FRONT LATE WED AFTERNOON/EVENING SPREADING EASTWARD ACROSS
THE AREA.
&&
.FIRE WEATHER...
ISSUED AT 332 AM CDT WED APR 8 2015
MAIN FIRE WEATHER CONCERNS LOOK TO ON THURSDAY.
EVEN WITH PLENTY OF LOW LEVEL MOISTURE...VERY HIGH FIRE DANGER
WILL BE IN PLACE OVER SOUTH CENTRAL AND SE KS DUE TO GUSTY SOUTH
WINDS. HOWEVER...THE CRITICAL FIRE WEATHER DAY LOOKS TO BE THU.
THIS IS WHEN STRONG NW WINDS WILL BE IN PLACE BY THE AFTERNOON
HOURS ALONG WITH RH`S IN THE 35-45% RANGE. WIND SPEEDS THU
AFTERNOON WILL BE IN THE 20-30 MPH RANGE WITH HIGHER GUSTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 79 56 71 38 / 30 30 10 0
HUTCHINSON 74 52 67 37 / 30 20 10 0
NEWTON 77 54 67 38 / 40 30 10 0
ELDORADO 80 60 69 40 / 40 40 10 10
WINFIELD-KWLD 82 61 72 41 / 40 30 10 0
RUSSELL 60 46 63 35 / 20 20 10 10
GREAT BEND 65 46 64 35 / 20 10 10 0
SALINA 70 50 65 35 / 30 30 20 10
MCPHERSON 72 51 66 36 / 30 30 10 10
COFFEYVILLE 82 65 76 43 / 40 40 30 10
CHANUTE 81 64 73 41 / 40 50 30 10
IOLA 80 63 72 40 / 40 50 30 10
PARSONS-KPPF 81 64 74 42 / 40 50 30 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
800 AM EDT WED APR 8 2015
.UPDATE...
ISSUED AT 745 AM EDT WED APR 8 2015
THE ARRIVAL OF LOWER CLOUDS FROM THE WEST HAS ALLOWED THE EARLIER
DENSE FOG TO BREAK UP AROUND DAWN. ACCORDINGLY...THIS UPDATE WAS
MAINLY TO REMOVE THE ADVISORY AND FOG MENTION...BUT ALSO UPDATED
THE POPS THROUGH NOON AND ADJUSTED TEMPS/DEWPOINTS PER THE LATEST
OBS AND TRENDS. THE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS ALONG WITH UPDATES TO THE ZFP AND HWO.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM EDT WED APR 8 2015
07Z SFC ANALYSIS SHOWS A STATIONARY BOUNDARY JUST NORTH OF
KENTUCKY PLACING THE AREA IN A WARM AND HUMID AIR MASS. THE
CONVECTION OF THE PAST DAY AND EVENING LEFT PLENTY OF GROUND
MOISTURE BEHIND AND NOW THAT CLOUDS ARE CLEARING OFF TO THE
EAST...EXPECT WIDESPREAD FOG TO DEVELOP AND BECOME LOCALLY DENSE
THIS MORNING. ALREADY JKL...SME...AND LOZ ARE SEEING DENSE FOG. AS
A RESULT...A DENSE FOG ADVISORY MAY BE NEEDED FOR MUCH OF THE
AREA THROUGH DAWN. OTHERWISE...TEMPERATURES ARE IN THE MID TO
UPPER 50S FOR MOST LOCATIONS WHILE DEWPOINTS ARE GENERALLY WITHIN
A DEGREE OF THE DRY BULB TEMP...ALSO WINDS REMAIN LIGHT AND
VARIABLE.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST. THEY ALL SHOW SOUTHWEST FLOW OVER
KENTUCKY WITH PACKETS OF ENERGY PASSING THROUGH THE REGION EVERY
FEW HOURS. SOME HEIGHT FALLS WILL GET INTO THE MIX LATE IN THE
PERIOD ON THURSDAY AS A LARGER TROUGH SWEEPS EAST AND INTO THE
UPPER MIDWEST. THE KEY TO THIS UNSETTLED PATTERN WILL BE THE
SMALLER FEATURES THAT THE HIGHER RESOLUTION MODELS HAVE A BETTER
CHANCE OF CATCHING. EVEN SO...THE CONFIDENCE IN ANY PARTICULAR
SOLUTION IS LOW SO THE FORECAST HAS AN ELEMENT OF HEDGING TO IT
WITH THE HRRR AND NAM12 FAVORED. THE NAM12 ACTUALLY DID A DECENT
JOB DEPICTING THE CONVECTION OF THE PAST DAY SO AM INCLINED TO
GIVE IT HIGHER WEIGHTING TODAY.
SENSIBLE WEATHER WILL LIKELY BE A REPEAT OF TUESDAY WITH A CLUSTER
OF STRONG TO SEVERE THUNDERSTORMS POSSIBLY DEVELOPING BY EARLY
AFTERNOON AND TRACKING THROUGH THE NORTHERN AND CENTRAL PORTION
OF THE CWA. THIS IS THE SAME PLACE THAT WAS HIT HARD YESTERDAY AND
PWS WILL BE SIMILAR TODAY...SO CONSIDERED A FLASH FLOOD WATCH FOR
THESE LOCATIONS. HOWEVER...THE UNCERTAINTY IS STILL TOO HIGH
BARRING OBVIOUS UPSTREAM DEVELOPMENT SO WILL HIT THIS THREAT WITH
AN SPS FOR NOW. THE CONVECTION SHOULD DIE DOWN LATER IN THE
EVENING WITH PATCHY FOG...LOCALLY DENSE AGAIN...A CONCERN. THE
SET UP REMAINS SIMILAR FOR STORMS ON THURSDAY...IF NOT A TAD
BETTER AS THE MAIN TROUGH APPROACHES. ACCORDINGLY...HAVE CONTINUED
THE FAIRLY HIGH CHANCES FOR SHOWERS AND STORMS INTO THURSDAY
AFTERNOON AND EVENING.
AGAIN USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR
THE WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON
TERRAIN FOR TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSE
TO OR A BIT HIGHER THAN A BLEND OF THE MAV AND MET VALUES THROUGH
THE PERIOD.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 421 AM EDT WED APR 8 2015
AN UPPER LEVEL TROUGH...WITH SEVERAL SHORTWAVES EMBEDDED AND
ROTATING WITHIN IT...WILL PUSH FROM THE UPPER MISSISSIPPI VALLEY
EASTWARD FROM 0Z FRIDAY AND THROUGH THE DAY FRIDAY. OVERNIGHT FRIDAY
AND INTO THE DAY SATURDAY...THIS WAVE WILL WEAKEN AND CONTINUE TO
SHIFT EASTWARD...WHILE BUILDING HEIGHTS AND DEAMPLIFIED RIDGING
TAKES HOLD ACROSS THE OHIO RIVER VALLEY. LONG RANGE MODELS ARE IN
AGREEMENT OF THIS FLOW BECOMING ZONAL THROUGH SUNDAY...WITH A
SHORTWAVE DEVELOPING AND RIDING EASTWARD ACROSS KY LATE IN THE DAY
AND CONTINUING INTO MONDAY. UNFORTUNATELY FOR THE REST OF THE
EXTENDED...THE FEATURES ARE WELL AGREED UPON...BUT THE TIMING AND
PLACEMENT IS NOT. SUNDAY NIGHT/MONDAY MORNING A UPPER LEVEL CLOSED
LOW WILL LIKELY DEVELOP OVER THE TX/NM AREA...CAUSING AMPLIFICATION
AND EVENTUALLY FALLING HEIGHTS ACROSS KY AS THE LOW STARTS TO MOVE
NEWARD DURING THE DAY MONDAY...LOSING CONSIDERABLE STRENGTH AS IT
REACHES THE UPPER MISSISSIPPI VALLEY BY TUESDAY. MULTIPLE WEAKER
SHORTWAVES WILL MOVE AROUND THESE CLOSED LOWS...TRAVELING DIRECTLY
INTO THE OHIO RIVER VALLEY.
AT THE SURFACE...A LOW PRESSURE SYSTEM WILL BE COLLOCATED WITH THE
UPPER LEVEL TROUGH ON FRIDAY AND FOLLOW THE TRACK NORTHEASTWARD
ACROSS THE GREAT LAKES. THIS WILL SEND A COLD FRONT EASTWARD AND
INTO THE STATE OF KY...STARTING OFF IN THE FAR WEST AROUND 0Z TO
3Z...AND REACHING THE JKL CWA BY LATE MORNING FRIDAY BEFORE QUICKLY
SHIFTING EASTWARD IN THE AFTERNOON...JUST AS THE UPPER LEVEL TROUGH
EXITS. BEST INSTABILITY AND MOISTURE WILL BE LOCATED ALONG AND JUST
AHEAD OF THE FRONT...WITH SHOWERS AND THUNDERSTORMS CHANCES EXPECTED
TO INCREASE THROUGH FRIDAY MORNING...BEFORE QUICKLY TAPERING OFF
ONCE THE FRONT PASSES THROUGH AND A STRONG SHOT OF DRIER AND COOLER
NRLY FLOW MOVES IN.
AS HEIGHTS BUILD SATURDAY INTO SATURDAY NIGHT...EXPECT SURFACE HIGH
PRESSURE TO BE IN CHARGE...WITH LIGHT WINDS AND GENERALLY CLEAR
SKIES. THE COULD CREATE SOME RIDGE VALLEY SPLIT CONDITIONS FOR
OVERNIGHT LOWS...AS WAS REFLECTED IN THE FORECAST. BY SUNDAY...THE
NEXT SHORTWAVE WILL BEGIN ENCROACHING UPON THE REGION...WITH YET
ANOTHER SURFACE LOW LOCATED JUST TO OUR SW. STRONG SRLY FLOW WILL
TAKE HOLD...WHICH COUPLED WITH INSTABILITY/LIFT FROM THE NEARBY
SYSTEM...WILL CREATE ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS SUNDAY EVENING AND INTO THE DAY MONDAY. FINALLY...THE
FUN CONTINUES AS SEVERAL MORE SHORTWAVES TRAVERSE THE UPPER LEVEL
TROUGH AND BRING UNSETTLED WEATHER TO THE REGION TO CONTINUE OUT THE
REMAINDER OF THE EXTENDED. GIVEN THE TIMING AND PLACEMENT
DISCREPANCIES OF THE LONG RANGE MODELS...CONTINUED WITH A MODEL
BLEND AT THIS TIME. HOWEVER...ONE NOTE...IF THE GFS40 MODEL PANS
OUT...SOME OF THESE SYSTEMS COULD PUT DOWN SOME HEAVY RAINS...WITH
PWATS TOPPING OUT ABOVE 1.3 TUESDAY AFTERNOON AND EVENING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 800 AM EDT WED APR 8 2015
THE FOG PROVED TO BE FLEETING THIS MORNING AS A LAYER OF LOW TO
MID CLOUDS MOVED IN AND CLEARED OUT THE LOWER VIS. LATER TODAY
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS EXPECTED THIS
AFTERNOON. HAVE STAYED WITH A VCTS FOR THIS WITH MORE REFINEMENT
POSSIBLE WITH FUTURE TAF ISSUANCES AS THE TIMING AND EFFECTS OF
THIS NEXT WAVE BECOME MORE CLEAR. AFTER THIS WAVE OF ACTIVITY
PASSES PATCHY FOG WILL BE A POSSIBILITY MAINLY...IN THE
VALLEYS...AND HAVE ADDED SOME TO THE SME AND LOZ TAFS. WINDS WILL
REMAIN MAINLY LIGHT FROM THE SOUTH...OUTSIDE OF ANY THUNDERSTORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1201 PM EDT WED APR 8 2015
.SYNOPSIS...
A BACKDOOR COLD FRONT WILL DROP SOUTH ACROSS THE LOCAL AREA EARLY
TODAY THROUGH TONIGHT. THE FRONT THEN WEAKENS AND LIFTS BACK
NORTH AS A WARM FRONT ON THURSDAY. ANOTHER COLD FRONT CROSSES THE
REGION LATE FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
FORECAST UPDATED TO LWR POPS FOR THE REMAINDER OF THE DAY AND MAKE
CHANGES TO HRLY TEMPS WHICH ARE QUITE TRICKY DUE TO A SLOWLY
SAGGING COLD FRNT THRU THE AREA.
PREVIOUS DISCUSSION...
LATEST SURFACE ANALYSIS FEATURES SFC LOW PRESSURE IN PLACE OVER
THE CENTRAL HIGH PLAINS, WITH A QUASI- STATIONARY FRONTAL BOUNDARY
DRAPED ACROSS THE MID MS VLY OVER INTO THE OHIO VLY AND THE LWR
EASTERN SHORE. NOTING SOME POCKETS OF SHRAS ACROSS THE AREA ON
REGIONAL RADAR MOSAIC IN ASSOCIATION WITH A FEW WEAK DISTURBANCES.
A FEW SCT SHRAS ARE CURRENTLY PUSHING EAST ON THE SOUTHERN
PERIPHERY OF THE FRONTAL ZONE ACROSS THE LWR EASTERN SHORE THIS
MORNING. MEANWHILE TO THE WEST, A MORE SUBSTANTIAL AREA OF SHRAS
IN ASSOCIATION WITH DECAYING CONVECTIVE COMPLEX THAT ROLLED ACROSS
THE OHIO RVR VALLEY LAST NIGHT IS CURRENTLY PUSHING FROM E
WV/WESTERN VA OVER TO THE PIEDMONT IN THE FORM OF SOME LIGHT TO
MODERATE RAIN SHRAS. LATEST HRRR AND TO A LESSER EXTENT THE 00Z
NAM HAVE BEST HANDLED THIS FEATURE THUS FAR... AND HAVE THEREFORE
LEANED THE FORECAST IN THIS DIRECTION FOR THE NEAR TERM. HAVE GONE
WITH A BRIEF 4-6 HR PERIOD OF LIKELY SHRAS THIS MORNING MAINLY IN
THE WARM SECTOR...WITH THE BEST RAIN CHANCES FROM THE EASTERN
PIEDMONT/WEST OF RIC METRO EARLY THIS MORNING...REACHING THE I-95
CORRIDOR BY DAWN AND EVENTUALLY SOUTH CENTRAL VA/HAMPTON ROADS BY
MID TO LATE MORNING. EXPECT LESS SHRA ACTIVITY THIS AFTN BEHIND
DEPARTING SHORTWAVE AND HV THEREFORE CUT BACK ON POP FOR THE AFTN.
EXPECT THE FRONT TO THE NORTH TO DROP SOUTH-SOUTHEAST IN BACKDOOR
FASHION THIS MORNING, BRINGING ABOUT A WIND SHIFT TO THE NE FROM
MIDDAY INTO THE AFTN. TEMPERATURES WILL STABILIZE TO FALL SLIGHTLY
ACROSS THE NORTHERN NECK/EASTERN SHORE, AS TEMPERATURES WARM INTO
THE LOW TO MID 70S IN THE WARM SECTOR OVER INLAND SECTIONS ALONG
AND SOUTH OF THE VA/NC BORDER. FARTHER NORTH, LOOK FOR HIGHS IN
THE U40S NEAR OCEAN CITY...LOW TO MID 50S OVER THE NORTHERN HALF
OF THE AREA.
EXPECT ANOTHER ROUND OF CONVECTION BY EARLY EVENING AS NEXT
DISTURBANCE NOW OVER THE MID MO VLY TRANSLATES EAST. WILL INCREASE
POP AGAIN BRIEFLY TONIGHT AS DISTURBANCE MOVES ALONG THE FRONT,
IN PLACE ALONG OR JUST SOUTH OF THE VA/NC BORDER THIS EVENING.
RAIN CHANCES DROP OFF AGAIN TONIGHT BEHIND THIS FEATURE
OVERNIGHT. COOLER TONIGHT IN MOIST NE FLOW BEHIND THE FRONT, WITH
LOWS IN THE 40S NE TO MID 50S SW SECTIONS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 448 AM EDT WED...
THE FRONT WILL WEAKEN, WITH DEVELOPING SW FLOW EVENTUALLY PUSHING
IT BACK NWD AS A WARM FRONT BY THU AFTN. HIGHS THU WILL RANGE
FROM THE 50S ON THE LWR ERN SHORE TO THE U60S TO L70S WITH MORE
TIME IN THE WARM SECTOR ACROSS FAR SWRN/WRN AREAS. HAVE MADE A
MODEST DOWNWARD ADJUSTMENT ACROSS THE NORTHERN HALF OF THE AREA
WITH ONGOING NE FLOW. POPS REMAIN IN CHANCE RANGE AS SEVERAL WEAK
DISTURBANCES WILL RESULT IN TWO PERIODS FOR SCT SHRAS...MAINLY
ACROSS THE NORTH IN THE MORNING AND ACROSS CENTRAL AND SOUTHERN
ZONES ALONG THE FROTNAL ZONE.
SFC LOW OVER THE PLAINS WILL TRACK NE INTO THE GREAT LAKES LATE
THU/FRI WITH THE ASSOCIATED COLD FRONT CROSSING INTO OUR AREA
FM THE WEST LATE IN THE DAY ON FRI/FRI NGT. CHANCES OF ADDITIONAL
SHRAS/STORMS INCREASE FM W TO E THRU THE DAY FRI...WITH THE BEST
CHANCE (60% POPS) IN THE AFTN/EVE HRS. SOME TSTMS MAY HAVE STRONG
GUSTY WINDS AND HEAVY RAIN...AND HV MAINTAINED THIS MENTION IN
THE HWO. MORE SUN/COMPRESSIONAL HEATING AHEAD OF FRONT WILL ALLOW
FOR MUCH WARMER TEMPS ON FRIDAY AS THE REGION RETURNS INTO THE
WARM SECTOR. LOOK FOR HIGHS IN THE MID 70S TO LOW 80S...WITH SOME
MID 80S POSSIBLE ACROSS THE SOUTH IF CLEARING OCCURS A BIT QUICKER
THAN PRESENTLY MODELED.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 446 PM EDT TUE...
SFC CDFNT TO PUSH OFF THE CST AFT MDNGT FRI NGT...TO BE FOLLOWED
BY HI PRES FM THE WNW BUILDING OVR THE RGN THIS WKND. CONTG HI
CHC/LIKELY POPS FRI EVE...THEN TAPERING OFF W-E THROUGH LT FRI
NGT/EARLY SAT MRNG. XPCG CLRG ON SAT AS DRYING AIR FM THE WNW
SPREADS OVR THE RGN. THE HIGH MOVES OFF THE CST BY EARLY NEXT
WK...RESULTING IN WNDS BECOMING SSW...AND MOISTURE GRADUALLY
INCRSG. LO TEMPS FRI NGT FM THE M50S NW TO ARND 60F SE. HI TEMPS
SAT IN THE L/M60S AT THE CST...TO L70S INLAND. LO TEMPS SAT NGT FM
THE M40S NW TO L50S SE. HI TEMPS SUN NR 60F AT THE CST...TO 65 TO
70F ELSW. HI TEMPS MON/TUE FM THE M60S TO M70S.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
A BACKDOOR COLD FRONT IS DROPPING SOUTH INTO FAR NERN COUNTIES OF
THE FA EARLY THIS MORNING. VARIABLE BR WITH VISIBILITIES RANGING
FROM 1-5SM ACROSS THE REGION...WITH POCKETS OF FG WITH
VISIBILITIES FROM 1/4-1/2SM. NORTH OF THE FRONTAL BOUNDARY...WINDS
ARE NE AROUND 10-15KT. SOUTH OF THE BOUNDARY...WINDS ARE LIGHT
FROM THE SOUTH. AS THE FRONT SAGS SWD TODAY...EXPECT SIMILAR WIND
SHIFTS AND SPEEDS AS THE DAY PROGRESSES. MEANWHILE...A DECENT
SWATH OF RAIN SHOWERS ARE PUSHING WWD INTO THE ERN PIEDMONT AS OF
08/0800Z. RAIN WILL CONTINUE TO PUSH EWD ACROSS THE REGION
TODAY...BECOMING MORE FOCUSED ACROSS THE SOUTH WHERE THE FRONTAL
BOUNDARY IS LOCATED. EXPECT A COMBINATION OF MVFR/IFR CIGS IN RAIN
SHOWERS TODAY. PRECIP COMES TO AN END BY MID TO LATE
EVENING...WITH AREAS OF FOG EXPECTED TO DEVELOP QUICKLY OVERNIGHT.
CIGS ARE EXPECTED TO BE AROUND 400FT AGL WITH VARIABLE
VISIBILITIES IN IFR/MVFR CATEGORIES. THE BACKDOOR FRONT STALLS
ACROSS THE CAROLINAS WED NIGHT/THU AND CONDITIONS SHOULD BE SLOW
TO IMPROVE THU MORNING. THE FRONT LIFTS NWD THROUGH THE REGION THU
NIGHT/EARLY FRI MORNING. BREEZY CONDITIONS ANTICIPATED FRI AHEAD
OF AN APPROACHING COLD FRONT WHICH IS EXPECTED TO CROSS THE REGION
FRI EVENING. HIGH PRESSURE RETURNS TO THE REGION SAT/SUN.
&&
.MARINE...
SFC LOW PRESSURE WILL MOVE ACROSS THE WATERS INVOF A BACKDOOR COLD
FRONT...WHICH IS DROPPING DOWN ACROSS THE VA EASTERN SHORE AS OF
300 AM THIS MORNING. WINDS ARE GENERALLY LIGHT FROM THE S-SW SOUTH
OF THE FRONT...WITH BREEZY N-NE WINDS 10-20KT WITH GUSTS AROUND
25KT NORTH OF THE FRONT. AM ALREADY SEEING AN INCREASE IN WIND
SPEEDS IN CHES BAY NORTH OF TANGIER ISLAND AND ALONG THE ATLANTIC
COAST FROM FENWICK ISLAND TO PARRAMORE ISLAND. THE FRONT WILL
GRADUALLY DROP SWD THROUGH THE REST OF TODAY...STALLING ACROSS THE
CAROLINAS TONIGHT INTO THU. EXPECT NNE WINDS TO INCREASE OVER THE
WATERS THROUGH TODAY WITH A BRIEF REPRIEVE TONIGHT. SPEEDS WILL
GENERALLY BE 10-20KT OVER BAY/RIVERS/SOUND AND 15-25KT OVER THE
COASTAL WATERS. SEAS ARE ALSO EXPECTED TO BUILD FROM 2-3FT TO
5-7FT NORTH OF CAPE CHARLES LIGHT...3-4FT SOUTH. ONSHORE FLOW
PERSISTS ON THU WITH AN UPTICK IN WIND SPEEDS TO 10-15KT DURING
THE AFTN/EARLY EVENING. SEAS SUBSIDE BELOW 5FT IN SRN WATERS BY
THU AFTN...WHILE SEAS LINGER AROUND 4-5FT NORTH OF PARRAMORE
ISLAND UNTIL EARLY EVENING. SCA FLAGS FROM FENWICK ISLAND TO CAPE
CHARLES GO INTO EFFECT AT 600 AM THIS MORNING AND WILL MAINTAIN
THAT START TIME BASED ON CURRENT OBSERVATIONS.
THE STALLED FRONT LIFTS NWD AS A WARM FRONT THU NIGHT INTO EARLY FRI
AND WINDS BECOME SLY. SEAS 2-3FT...WAVES 1-2FT. SPEEDS BEGIN TO
INCREASE AROUND SUNRISE FRI MORNING AND WILL CONTINUE TO BE BREEZY
DURING THE DAY AHEAD OF AN APPROACHING COLD FRONT. SPEEDS WILL
AVERAGE 15-20KT (GUSTS UP TO 25KT OVER COASTAL WATERS). SEAS BUILD
TO 3-4FT AND MAY REACH UP TO 5FT NEAR BUOY 44009 BY LATE FRI
AFTN/EARLY EVENING. THE COLD FRONT CROSSES THE WATERS FRI NIGHT. THE
COOLER AIRMASS BEHIND THE FRONT DOES NOT ARRIVE UNTIL DURING THE DAY
ON SAT. A DAYTIME ARRIVAL OF COOLER AIR WILL DECREASE CHANCES FOR
POST-FRONTAL SCA WINDS. EXPECT NW WINDS ON SAT AOB 15KT...DECREASING
SAT NIGHT AS HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST AND
SETTLES OVER THE WATERS ON SUN/SUN NIGHT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THURSDAY FOR ANZ652-654.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ650.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAS/MAM
SHORT TERM...MAS/MAM
LONG TERM...ALB
AVIATION...BMD
MARINE...ALB/BMD
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1004 AM CDT Wed Apr 8 2015
.MESOSCALE DISCUSSION...
Issued at 1004 AM CDT WED APR 8 2015
Convection continuing to role east across the CWA this morning along
the heels of an 850-hPa low-level jet. Bulk of severe now centered
well east of the KC metro and as a result...have trimmed the western
two tiers of counties from Severe Thunderstorm Watch 31.
Additionally...plenty of obs still reporting widespread fog across
the region and have extended to inherited dense fog advisory through
11 AM.
Once this morning/s activity exits to the east...eyes will quickly be
drawn upstream to renewed convective development across the central
Plains. Latest HRRR has convection firing over south-central KS by
20z in the form of loosely organized single cells. After
developing...all models (both high-resolution convection allowing and
standard operational) show convection quickly lifting northeast into
the CWA by late afternoon. Right now the biggest concerns will be for
locations south of Interstate 70 as these areas will likely have the
best potential of seeing recovery following the passage of the warm
front later this morning/early afternoon. With plenty of dynamics
aloft...expect activity to quickly become severe as it moves into our
area with large hail...damaging winds...and isolated tornadoes all
possible. Convection later today/evening may come in a few waves as
additional shortwave energy embedded with strong southwest flow aloft
leads to renewed development along/near the cold front draped across
south-central Kansas. In any event...will continue to monitor and
update as needed.
UPDATE Issued at 538 AM CDT WED APR 8 2015
Warm air wing of convection has developed more early this morning
across eastern Kansas with storms quickly approaching the Missouri
border at this time. Storms north of I-70 are elevated in nature and
have stayed below severe warning limits, though large hail may be
possible if the shear above the boundary layer inversion can organize
the storms somewhat this morning. Storms farther south, generally
south of a Paola Kansas to Warrensburg Missouri, Marshall and
Moberly line, will have more opportunity to develop severe weather
this morning. These storms will be in the vicinity of the boundary
left over from last night which might help these storms get a better
connection to deep layer shear and instability. Continue to think that
the activity north of the Missouri River will keep the inverted
surface trough anchored along our southeast border through the
morning. For this reason, have added areas of fog and drizzle this
morning to the western half of the forecast area.
&&
.DISCUSSION...
Issued at 403 AM CDT WED APR 8 2015
Looks like more storms are in store for eastern Kansas and Missouri
today. Overnight activity took awhile Tuesday evening to get going,
but once the the cap was broken there where several rather strong
storms, which could have been much stronger if there had been upper
level dynamics to support the storms. The difference today is that a
significant trough is moving into the Plains States, which will
provide any storms this afternoon or this evening with plenty of
upper level support for strong robust severe thunderstorms. But,
first to what will happen this morning.
Today - This Morning: Early this morning an inverted surface trough
remains anchored from southeast Kansas northeast through northeast
Missouri, with the resulting boundary residing within the trough
along our southeast county warning area border. A verity of model
solutions have now coalesced on keeping this inverted surface trough
in place through the morning and, possibly, through the first part
of the afternoon. Additionally...it`s noted that storms are bubbling
back up across east central Kansas in the elevated environment north
of the trough thanks to isentropic assent on the 40 knot southwest
nocturnal jet. Thoughts are that these early morning storms will
likely not be severe due to their elevated nature, though marginally
large hail can not be ruled out. More general thinking is that this
area of storms will advect northeast into northern Missouri, staying
on the cool side of the inverted trough. As a result, have added
patchy fog into the northwest half few the CWA for this morning, and
nudged afternoon highs near the Iowa border down a degree or two;
but did up POPs for the morning, though they may need updating based
on radar trends as the forecast becomes valid later this morning.
Also, these morning storms could limit our instability early in the
day, delaying the potential onset time for afternoon/evening
activity. So, while another round of activity might wait to fire up
in the late afternoon and evening hours, it is still expected to
occur.
Today - This Afternoon and Tonight: Expect the inverted trough to
remain where it is till early afternoon when sufficient pressure
falls begin across the Plains in response to the trough over the
Great Basin shifting east, lifting the trough north as a warm front
this afternoon. As this occurs, the environment that was rather well
capped could rapidly lose that cap with any little shortwave
undulation present in the flow aloft, resulting in fast development
of strong and severe thunderstorms. Currently, expect storms to
develop along the southern end of the inverted trough as it starts
moving north this afternoon --after 20Z-- in southeast Kansas. MUCAPE
values of 4000+ J/KG and 0-6KM shear of possibly 40 to 50 knots would
make supercell thunderstorms possible from the first initial storms.
Expect this activity to spread northeast through west central
Missouri into northern Missouri during the late afternoon and evening
hours Wednesday, with storms likely crossing into our area between 5
and 7 PM this evening. Uncertain as to how far into the overnight
hours the strong and severe convection will last, but currently there
looks to be a bit of a dry slot that works in across northwest
Missouri as associated surface low lifts from Kansas into Iowa. this
should bring the threat for severe storms to an end by midnight,
though lingering storms could persist into Thursday. Thoughts persist
that all types of severe weather may accompany our storms today, with
large hail --larger than 2 inches-- strong damaging winds and
isolated tornadoes possible.
Thursday: The upper level trough responsible for our recent storms
will be swinging past us to the north. The surface low moving into
Iowa that morning will drag a Pacific cold front through the region
that day. The cool air behind the front will lag far enough back to
not be very notable till Friday. However, this front might be able to
generate some showers and or isolated thunderstorms as it moves
through, though no severe weather.
Friday and through the Weekend: Cooler conditions will prevail
Friday as a cool, but dry, air mass wafts through Kansas and
Missouri. Temperatures will warm back into the 70s for the weekend.
Saturday looks nice and dry, but by Saturday night through Sunday
and into Monday a significant rain event may develop.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 721 AM CDT WED APR 8 2015
Fog and thunderstorms greeted the terminals along the Kansas-Missouri
border this morning. Location of a front across central Missouri
indicates that the fog may linger well into the morning with easterly
winds through the morning. Thunderstorm activity currently at the
terminals early this morning will move east and is expected to not
redevelop until this afternoon. Expect the front to lift north this
afternoon allowing winds to veer to the south late this afternoon and
this evening and becoming gusty as the pressure gradient tightens.
Additionally, more storms are expect late this afternoon into this
evening which might affect the terminals.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...DENSE FOG ADVISORY until 11 AM CDT this morning FOR KSZ025-057-
102>105.
MO...DENSE FOG ADVISORY until 11 AM CDT this morning FOR MOZ020-021-
028>031-037>040-043>046.
&&
$$
MESOSCALE DISCUSSION...32
UPDATE...Cutter
DISCUSSION...Cutter
AVIATION...Cutter
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
645 AM CDT WED APR 8 2015
.SYNOPSIS...
ISSUED AT 342 AM CDT WED APR 8 2015
H5 ANALYSIS FROM EARLIER THIS EVENING HAD A CLOSED LOW OVER NRN
CALIFORNIA WITH A TROUGH OF LOW PRESSURE EXTENDING SWD INTO SO
CALIFORNIA. SWLY FLOW ALOFT EXTENDED FROM THE SWRN CONUS NEWD INTO
THE ROCKIES AND PLAINS STATES. WV IMAGERY TONIGHT HAS THE BULK OF
MID AND UPPER LEVEL MOISTURE WITH THIS FEATURE ACROSS MEXICO AND
TEXAS. FURTHER NORTH...MAINLY DRY MID AND UPPER LEVELS WERE
NOTED...HOWEVER A SMALL DISTURBANCE...HAS SPREAD MID LEVEL CLOUDS
AND SHOWERS TO THE NORTHWESTERN CWA TONIGHT...WITH AN OCCASIONAL
LIGHTNING STRIKE NOTED. FOR THE REMAINDER OF THE FORECAST AREA...A
MOIST BOUNDARY LAYER AND EASTERLY WINDS...HAS LED TO ANOTHER NIGHT
OF LOW CLOUDS...FOG AND DRIZZLE. AT THE SURFACE...A STATIONARY
FRONT EXTENDED FROM AROUND COLORADO SPRINGS...SEWD TO THE KS/OK
BORDER. NORTH OF THE FRONT...EASTERLY WINDS AND MOSTLY CLOUDY
SKIES WERE PRESENT ACROSS ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA. AS OF 3 AM CDT...TEMPERATURES RANGED FROM 39 AT
VALENTINE AND AINSWORTH TO 43 AT IMPERIAL AND OGALLALA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CDT WED APR 8 2015
THE MAIN FORECAST CHALLENGE OVER THE NEXT TWO PERIODS IS
PRECIPITATION CHANCES AND PRECIPITATION TYPES OVERNIGHT TONIGHT.
FOR TODAY...EASTERLY WINDS WILL CONTINUE TO FAVOR LOW CLOUDS FOR
MOST OF THE FORECAST AREA. SOME CLEARING IS POSSIBLE IN THE
PANHANDLE ZONES AND ACROSS FAR SWRN PORTIONS OF THE CWA THIS
AFTERNOON...PER HRRR AND NAM12 H85 AND H85-H90 RH FIELDS. WITH
THIS IN MIND...FILTERED SUN WILL LEAD TO HIGHS IN THE UPPER 50S.
ELSEWHERE...HIGHS WILL RANGE FROM THE UPPER 40S TO LOWER 50S. LATE
THIS AFTERNOON AS THE UPPER LEVEL LOW PUSHES EAST INTO WESTERN
WYOMING...NRN UT AND NWRN COLORADO ELEVATED AND SURFACE BASED
INSTABILITY WILL BEGIN TO INCREASE ACROSS THE PANHANDLE. THE
LATEST NAM12 IS INDICATIVE OF NEGATIVE LI`S ACROSS THE PANHANDLE
FROM 21Z THROUGH 03Z AND ACROSS PORTIONS OF SWRN NEBRASKA WITH
ELEVATED INSTABILITY FROM 00Z THROUGH 06Z THIS EVENING. DID GO
AHEAD AND INTRODUCE THUNDERSTORMS TO THE FORECAST IN THE FAR WEST
AND SWRN CWA FOR LATE THIS AFTERNOON AND EVENING IN LIGHT OF THE
NEGATIVE LI/S. AS FOR PCPN CHANCES...THE HIGHEST POPS WILL
CONTINUE IN THE WEST AND NORTHWEST...TRANSITIONING ACROSS THE
SANDHILLS AND NORTH CENTRAL NEBRASKA OVERNIGHT. THESE AREAS ARE IN
THE MOST FAVORABLE AREAS FOR ISENTROPIC LIFT AHEAD OF THE APPG
TROUGH THIS EVENING...THEN IN THE WRAP AROUND OVERNIGHT. AS FOR
PRECIPITATION TYPE OVERNIGHT...DECIDED TO KEEP THE BULK OF PCPN AS
ALL RAIN AS BUFKIT SOUNDINGS INDICATE ONLY A 1 TO 2 HOUR WINDOW
FOR CHANGEOVER TO SNOW...AND THIS IS MAINLY THURSDAY MORNING
ACROSS THE FAR NORTHWESTERN AND NORTHERN CWA. DECIDED TO WORD THE
FCST AS RAIN OR SNOW...AS LOWS ARE ONLY EXPECTED TO DROP INTO 33
TO 35 DEGREE RANGE IN THE NORTHWEST OVERNIGHT. AS FOR SNOW
ACCUMS...DECIDED TO KEEP THESE AT A MINIMUM AS IT IS EXPECTED TO
MIX WITH RAIN...AND WARM GROUND CONDS SHOULD LIMIT ANY ACCUMS IF
THEY DO OCCUR.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 342 AM CDT WED APR 8 2015
UPPER LEVEL TROUGH AND ASSOCIATED COLD POOL WILL WORK EAST ACROSS
THE FORECAST AREA ON THURSDAY. PRECIPITATION IS EXPECTED TO
CONTINUE THROUGH MUCH OF THE MORNING HOURS...BUT BEGIN TO WANE IN
THE AFTERNOON AS SYSTEM RELATIVE UPGLIDE ASSOCIATED WITH A FRONTAL
BOUNDARY SHIFTS SOUTH AND EAST. IN ADDITION...LARGE SCALE LIFT
DECREASES AS THE TROUGH AXIS WORKS INTO EASTERN IOWA BY MID
AFTERNOON. PRECIPITATION AMOUNTS ARE ANTICIPATED TO BE LIGHT
DURING THE DAYLIGHT HOURS. MOST LOCATIONS WILL ONLY ACCUMULATE A
FEW ADDITIONAL TENTHS AT MOST. WHAT CONTINUES TO BE THE GREATEST
ENIGMA WITH THIS SYSTEM IS WHEN AND IF A CHANGE OVER TO SNOW WERE
TO OCCUR. ENOUGH MID AND UPPER LEVEL COOLING WILL HELP WITH THE
CHANGE OVER...ESPECIALLY SINCE H85-H9 TEMPERATURES FALL BELOW 0C
AFTER 12Z ACROSS OUR NORTHWEST THURSDAY MORNING. WOULD EXPECT THAT
THE FROZEN HYDROMETEOR WOULD MAKE IT TO THE SURFACE...BUT SFC T/S
ARE SHOWN LARGELY TO REMAIN JUST ABOVE 0C. CURRENT THINKING IS
THAT A CHANGE OVER WILL OCCUR...AFTER SUNRISE THURSDAY...BUT THEN
QUICKLY CHANGE BACK TO ALL RAIN AS THE DIURNAL HEATING TAKES
CONTROL. WHERE THERE IS ENHANCEMENT OF QPF FALLING AS SNOW...SOME
ACCUMULATION MAY OCCUR FOR AN HOUR OR TWO PERIOD. HOWEVER WITH THE
RECENT WARM SPELL GROUND TEMPERATURES WOULD SUPPORT MELTING...THUS
ACCUMULATIONS WOULD BE INSIGNIFICANT...A COUPLE TENTHS AT MOST.
NORTHWEST FLOW WILL TRANSPORT COOLER AIR INTO THE REGION
OVERNIGHT...WITH MORNING LOWS BELOW 0C FOR THE ENTIRE CWA FRIDAY
MORNING.
RETURN FLOW AND TRANSITORY UPPER RIDGING WILL PROMOTE A QUICK
WARM-UP ON FRIDAY. HIGHS WILL CLIMB BACK INTO THE 60S. THE RETURN
FLOW WILL ALLOW FOR AN INCREASE IN MOISTURE ACROSS THE HIGH PLAINS
AND WEST CENTRAL NEBRASKA. A THETA-E GRADIENT NOSES INTO THE
FORECAST AREA EARLY SATURDAY. ELEVATED INSTABILITY DEVELOPS ALONG
THE GRADIENT...WITH LI/S APPROACHING -5C BY SATURDAY AFTERNOON. A
FEW ELEVATED STORMS ARE POSSIBLE.
SUNDAY...A SIMILAR SETUP IS IN PLACE HOWEVER THE MODELS SHOW A COLD
FRONT ADVANCING ACROSS THE CWA EARLY AFTERNOON. MODEL CONSISTENCY
IS NOT TOO STRONG AT THIS POINT...BUT SUFFICIENT ENOUGH FOR A
MENTION OF THUNDERS ONCE AGAIN ESPECIALLY ALONG AND SOUTH OF THE
FRONT. WILL NEED TO WATCH AS PRE-FRONTAL CONDITIONS WOULD HAVE
SLIGHTLY MORE ENERGY TO WORK WITH.
THE PATTERN REMAINS ACTIVE EARLY NEXT WEEK...AND WILL HAVE TO WATCH
THE PROGRESSION OF A SOUTHERN STREAM CLOSED LOW...WHICH MAY BRING
ADDITIONAL CHANCES OF QPF TO THE REGION. THE INIT GAVE US SLIGHT
CHANCES...WHICH IS REASONABLE GIVEN A LACK OF CONSISTENCY IN THE
LONG RANGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 645 AM CDT WED APR 8 2015
AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL SPREAD ABUNDANT CLOUDS
AND THE THREAT FOR RAIN AND CONTINUED LOW CIGS ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA OVER THE NEXT 24 HOURS. FOR THE KLBF
TERMINAL...LIFR CIGS UNDER 1000 FT AGL WILL CONTINUE THROUGH MID
MORNING...WITH MVFR CIGS OF 1200 TO 1800 FT AGL AFTER 15Z. SOME
LIMITED CLEARING WILL BE POSSIBLE AT THE KLBF TERMINAL LATER THIS
AFTERNOON WITH OVERCAST SKIES EXPECTED AFTER 01Z THURSDAY. LIGHT
RAIN WILL BE POSSIBLE AFTER THE LATE EVENING HOURS...WITH CIGS
DROPPING DOWN TO UNDER 1000 FT AGL OVERNIGHT. FOR THE KVTN
TERMINAL...EXPECT LIFR CIGS UNDER 1000 FT AGL THIS MORNING. MVFR
CIGS OF 1500 FT AGL ARE EXPECTED THIS AFTERNOON. FOR
TONIGHT...CIGS WILL LOWER TO UNDER 1000 FT AGL WITH RAIN EXPECTED
AFTER 04Z THURSDAY. PERIODIC VISIBILITIES DOWN TO 4SM ARE POSSIBLE
AS WELL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...JACOBS
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
959 AM EDT WED APR 8 2015
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTH INTO THE REGION THIS AFTERNOON AND
STALL OVER THE AREA TONIGHT. THE FRONT WILL LIFT NORTH OF THE
REGION LATE THURSDAY. A COLD FRONT WILL APPROACH FROM THE WEST
LATE FRIDAY AND MOVE OFFSHORE SATURDAY MORNING. HIGH PRESSURE WILL
EXTEND OVER THE AREA FROM THE NORTH SATURDAY NIGHT AND SUNDAY. A
WARM FRONT WILL LIFT NORTH OF THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 10 AM WEDNESDAY...ONE AREA OF PRECIP ALBEMARLE SOUND REGION
AND NORTHERN OUTER BANKS MOVG OFFSHORE AND ANOTHER DVLPG JUST W OF
THE NRN COASTAL PLAINS. THE 4 KM WRF MODEL SHOWS AREA OF
CONVECTION MOVG INTO THE NRN COASTAL PLAINS AND PROGRESSING E-SE
ACRS THE AREA THROUGH ABT 18Z. GIVEN RADAR TRENDS...AND ADDITIONAL
FOCUS OF BACKDOOR FNT ACRS NERN AREAS WILL RAISE POPS TO LIKELY
WITH MODERATE SHOWERS AND HIGHER QPF VALUES ACRS THE NRN TIER CWFA
AND EXTEND THROUGH EARLY AFTN. WILL CONT WITH HIGH CHC 40% POPS
FOR SRN TIER THROUGH EARLY AFTN AS WELL. H5 IMPL WORKING THROUGH
THE AREA HELPING TO INITIATE CONVECTION LATE THIS MORN THROUGH
EARLY AFTN. LIKELY WILL SEE SUBSIDENCE IN THE WAKE OF THE WAVE
WITH CONVECTION DIMINISHING BUT WITH UNSTABLE AMS WITH TEMPS IN
THE LWR 80S AND FOCUS OF BACKDOOR FNT WILL KEEP LOW CHC POPS ALL
BUT IMMEDIATE COAST WHERE WILL HAVE SLGT CHC POPS FOR THE RMNDR OF
THE AFTN. OTRW...MADE MINOR TWEAKS TO INIT T/TD.
PREV DISC...VERY DIFFICULT FORECAST NEXT 36 HOURS IN TRYING TO
PROVIDE DETAIL REGARDING PRECIPITATION CHANCES IN THE MOIST BUT
WEAKLY FORCED ATMOSPHERE OVER THE CAROLINAS. ZONAL FLOW WILL
CONTINUE ALBEIT WITH RIDGING AND ASSOCIATED SUBTLE HEIGHT RISES
OVER THE SOUTHEAST STATES THROUGH THURSDAY. WEAK LOW AMPLITUDE MID
LEVEL WAVES IN THIS FLOW WILL HAVE THE POTENTIAL TO ENHANCE
PRECIPITATION CHANCES ESPECIALLY IF THE ORGANIZED CONVECTION
EXPECTED OVER THE PLAINS TODAY TRIGGERS A STRONGER MCV WHICH WOULD
THEN MOVE EASTWARD TONIGHT. THE LARGE SCALE MODELS HAVE BEEN
HAVING A DIFFICULT TIME IN HANDLING THIS SITUATION SO HAVE A
RELIED ON THE HRRR AND THE HIGH RESOLUTION NMM AND WRF MODELS TO
TRY TO GET A BETTER HANDLE ON THIS. TEMPERATURES WILL BE ABOVE
NORMAL TODAY IN THE SOUTHERLY PRE FRONTAL FLOW WITH HIGHS INLAND
IN THE LOWER 80S AND LOWER 70S BEACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 400 AM WEDNESDAY...THE BACK DOOR FRONT WILL SAG SOUTH TO
NEAR THE CRYSTAL COAST OVERNIGHT THEN STALL. STILL UNCERTAIN ON
PRECIPITATION DETAILS SO WILL FORECAST 30-50% POPS HIGHEST OUTER
BANKS. LOWS ARE FORECAST TO CONTINUE MILD WITH READINGS IN THE
UPPER 50S/LOWER 60S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 330 AM WEDNESDAY...00Z MODELS HAVE COME INTO BETTER
AGREEMENT WITH BACKDOOR FRONT STALLING OVER SRN SECTIONS LATE WED
NIGHT...THEN RETREATING NORTH ON THU. ECWMF AND GFS ALSO IN GOOD
AGREEMENT THAT STRONGER COLD FRONT WILL MOVE IN FRIDAY NIGHT AND
BE NEAR COAST SAT MORNING...THUS INCREASED POPS FRI NIGHT AND
DECREASED INLAND SAT.
THURSDAY AND THURSDAY NIGHT...SFC FRONT EXPECTED TO RETREAT NORTH
DURING THE DAY WITH WEAK RIDGING ALOFT. LACK OF UPR SUPPORT
EXPECTED TO LIMIT CONVECTIVE DEVELOPMENT BUT KEPT 20% POPS WITH
FRONT MOVING BACK NORTH. DID DROP POPS FOR THU NIGHT WITH MODELS
INDICATING PCPN THREAT WEST AND NORTH OF AREA. MOS GDNC CONTINUES
TO HAVE LARGE DIFFERENCES ON HIGH TEMPS WITH GFS COOLER AND NAM
WARMER DUE TO HANDLING OF FRONT. UPDATED PREVIOUS FCST WITH LEAN
TO COOLER GFS...HIGHS RANGING FROM AROUND 80 SOUTH TO 65-70 NORTH.
FRIDAY THROUGH SATURDAY...VERY WARM TEMPS EXPECTED FRIDAY AHEAD
OF A STRONGER COLD FRONT APPROACHING FRIDAY NIGHT. NO CHANGE TO
PREVIOUS THINKING FOR SHOWERS AND THUNDERSTORMS FRIDAY FOR INLAND
SECTIONS AS DECENT INSTABILITY AND UNIDIRECTIONAL WEST-SOUTHWEST
FLOW IS ENOUGH TO SUPPORT CHC POPS IN AFTERNOON INLAND OF SEA
BREEZE. LOW LEVEL THICKNESSES SUPPORT MID 80S FOR INLAND SECTIONS.
LATEST MODELS AGREE ON MAIN THREAT OF SHOWERS AND TSTMS ALONG AND
AHEAD OF COLD FRONT FRIDAY NIGHT...AND INCREASED POPS TO 60% ALL
ZONES...MAINLY FOR WRN HALF DURING EVENING AND ERN HALF OVERNIGHT.
CONCUR WITH SPC OUTLOOK OF SLIGHT RISK OF SVR WITH SUFFICIENT MID
LVL SHEAR TO SUPPORT ORGANIZED STRONG CONVECTION.
FRONT EXPECTED TO MOVE OFFSHORE SAT MORNING AND HAVE LOWERED POPS
TO INDICATE DRIER TREND. MAX TEMPS ABOUT 10 DEGS COOLER THAN
FRIDAY WITH MID 70S INLAND TO LOWER 60S NRN OBX.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...STRONG HIGH PRES WILL EXTEND
OVER AREA FROM NORTH SAT NIGHT AND SUNDAY AND GRADUALLY MOVE EAST
SUN NIGHT. DRY CONDITIONS EXPECTED WITH TEMPS NEAR NORMAL.
MONDAY INTO TUESDAY...NO CHANGE TO PREVIOUS FCST. HIGH PRES WILL
CONTINUE MOVING OFFSHORE WITH MOIST S TO SW FLOW RETURNING. SLIGHT
CHC POPS FOR SW HALF OF AREA MONDAY AND MON NIGHT...INCREASING TO
20-30% ALL AREAS TUESDAY. MAIN TEMP CHANGE WILL BE MIN TEMPS 10-15
DEGS ABOVE NORMAL MON NIGHT.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 10 AM WEDNESDAY...DIFFICULT FORECAST WITH PRECIPITATION
APPROACHING THE TAF SITES FROM THE WEST. PRECIPITATION WILL
AFFECT THE TAF SITES ON AND OFF FM 14-18Z WITH BRIEF MVFR
CONDITIONS POSSIBLE IN HEAVIER SHOWERS AND STORMS. VFR CONDITIONS
EXPECTED OUTSIDE OF SCATTERED SHOWER/THUNDERSTORM ACTIVITY THROUGH
THIS EVENING. GUIDANCE IS AGAIN POINTING TO THE POTENTIAL FOR IFR
CONDITIONS REDEVELOPING AGAIN LATE THIS EVENING AS THE BL REMAINS
SATURATED BUT CONFIDENCE IN THIS LOW DUE TO RECENT TENDENCY FOR
GUIDANCE TO OVER FORECAST THESE CONDITIONS. LOW LEVEL EASTERLY
FLOW BEHIND THE BACK DOOR FRONT MAY BE MORE CONDUCIVE TO IFR
CONDITIONS THOUGH SO WILL HAVE TO CONTINUE TO MONITOR.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 400 AM WEDNESDAY...SOME LOWER CIGS COULD PERSIST THURS
MORNING WITH LOW LEVEL NE FLOW. VFR MAINLY EXPECTED THURS NIGHT
INTO FRIDAY...THEN HIGHER THREAT OF SUB-VFR CONDITIONS FRI NIGHT
INTO EARLY SAT WITH GOOD COVERAGE OF SHOWERS AND TSTMS EXPECTED
AS STRONGER FRONT MOVES INTO AREA. GUSTY SW WINDS 15-25 MPH LIKELY
FRIDAY AHEAD OF FRONT. HIGH PRESSURE WILL ALLOW AVIATION
CONDITIONS TO IMPROVE TO VFR SATURDAY EVENING THROUGH SUNDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 10 AM WEDNESDAY...NO SIG CHANGES ON UPDATE. WINDS WILL
REMAIN 15 KT OR LESS THROUGH TONIGHT. THE MAIN FEATURE WILL BE A
BACK DOOR COLD FRONT WHICH IS FORECAST TO PUSH SOUTH INTO THE
NORTHERN WATERS/ALBEMARLE SOUND TODAY THEN CONTINUE SOUTH TONIGHT
INTO THE CENTRAL WATERS/PAMLICO SOUND WHERE IT WILL STALL. EXPECT
WINDS TO VEER FROM SOUTHERLY THIS MORNING TO SOUTHWEST TO WEST BY
THIS AFTERNOON THEN TO NORTH AND NORTHEAST BEHIND THE FRONT LATER
TODAY AND TONIGHT. SEAS WILL REMAIN IN THE 2-4 FT RANGE THROUGH
THE PERIOD.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 400 AM WEDNESDAY...CONTINUED PREVIOUS FCST THINKING WITH
WINDS GRADUALLY RETURNING TO S-SW DURING THE DAY THU AS FRONT
RETREATS BACK NORTH. MAIN CHANGE WAS TO INDICATE FASTER COLD FRONT
PASSAGE SAT MORNING WITH LATEST MODELS IN GOOD AGREEMENT. STILL
EXPECT STRONGEST WINDS FRI AND FRI NIGHT AHEAD OF FRONT...SW
15-25 KT WITH SEAS BUILDING TO SMALL CRAFT ADVISORY LEVELS FRI
AFTN INTO EARLY SAT. NE SURGE 10-20 KT EXPECTED LATE SAT THROUGH
SUNDAY. ADJUSTED SEAS WITH LATEST NWPS. HEIGHTS MAINLY 3-4 FT
THU...BUILDING TO 4-6 FT FRI-FRI NIGHT...THEN DIMINISHING 2-4 FT
SUNDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JME
NEAR TERM...JAC/JME
SHORT TERM...JME
LONG TERM...JBM
AVIATION...JAC/JME/JBM
MARINE...JAC/JME/JBM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
819 AM EDT WED APR 8 2015
.SYNOPSIS...
UNSEASONABLY WARM AND HUMID WEATHER WILL PREVAIL OVER THE NEXT
FEW DAYS...AS HIGH PRESSURE OFFSHORE CIRCULATES BALMY AIR INTO
THE REGION. SHOWERS AND A FEW THUNDERSTORMS WILL ACCOMPANY THE
MILD CONDITIONS...WITH RAIN CHANCES INCREASING FRIDAY NIGHT AND
SATURDAY MORNING ASSOCIATED WITH A FRONTAL PASSAGE. A DRYING TREND
WITH SEASONABLE TEMPERATURES WILL ARRIVE FOR THE REMAINDER OF THE
WEEKEND...WITH A WARMING TREND EXPECTED EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 600 AM WEDNESDAY...THE LAST OF THE SHORTWAVE ENERGY WAS
PIVOTING ACROSS FORECAST AREA. A FEW VERY LIGHT SHOWERS WERE
ONGOING...BUT WERE ENDING WEST OF INTERSTATE 95. THE HIGH
RESOLUTION HRRR MODEL WAS INDICATING A SLIGHT REJUVENATION IN THIS
ACTIVITY ACROSS THE CAPE FEAR RIVER AREA AFTER SUNRISE AND HAVE
INCLUDED HIGHEST MORNING POPS HERE. THE TROUGH WILL BE OFFSHORE BY
MID MORNING.
CURRENT THINKING IS THAT IN THE WAKE OF THE MID-LEVEL TROUGH...
SUBSIDENCE WILL BE ON THE INCREASE MID AND LATE MORNING.
HOWEVER...THE COLUMN IS EXPECTED TO BECOME QUITE UNSTABLE WITH
MIXED LAYER CAPE VALUES ON THE ORDER OF 1500-2000 J/KG...HIGHEST
THIS AFTERNOON. DO NOT SEE ANY DISCERNIBLE FEATURES ALOFT TO
TRIGGER ANYTHING MORE THAN AIRMASS SHOWERS AND THUNDERSTORMS. THE
INLAND PENETRATING SEABREEZE BOUNDARY AND RESIDUAL OUTFLOW
BOUNDARIES MAY BECOME POINTS OF CONVECTIVE INITIATION/ORGANIZATION.
RATHER WARM AND RELATIVELY DRIER AIR ALOFT MAY ALSO ACT TO HINDER
CONVECTION THIS AFTERNOON.
WILL CAP POPS AT SLIGHT CHANCE/SMALL CHANCE FOR THE REMAINDER OF
THE DAY. CONCERN FOR TONIGHT IS THAT WITH A POTENT...BUT
DAMPENING MID-LEVEL TROUGH APPROACHING FROM THE WNW...ITS
ASSOCIATED COOLER AIR IN THE MID LEVELS MAY HELP TO MAINTAIN
UPSTREAM CONVECTION AS IT MOVES INTO THE EASTERN CAROLINAS.
THUS...WILL SHOW MAINLY SCATTERED SHOWERS AND SOME THUNDERSTORMS...
LIKELY MOST NUMEROUS ACROSS INLAND PORTIONS OF SOUTHEAST NORTH
CAROLINA AND THE ADJACENT PEE DEE REGION OF SOUTH CAROLINA.
CONSIDERABLE CLOUD COVER IS EXPECTED TO GIVE WAY TO SIGNIFICANT
BREAKS OF SUNSHINE AND WITH THAT...EXPECT TEMPS WELL UP INTO THE 80S
INLAND TODAY WHERE RECORDS AT KLBT AND KFLO ARE 90 DEGREES. ALONG
THE COAST...THE SEABREEZE IS EXPECTED TO MAKE DECENT INLAND
PROGRESS...ESPECIALLY ACROSS NORTH CAROLINA AND SO WILL CAP HIGHS IN
THE CAPE FEAR REGION IN THE UPPER 70S AND LOWER 80S. THE MORE
IMMEDIATE CAROLINA COAST WILL LIKELY BE STYMIED IN THE MID 70S WITH
SOME BEACHES IN THE LOWER 70S. ANOTHER BALMY NIGHT UPCOMING WITH
LOWS TONIGHT REMAINING WELL ABOVE NORMAL...LOWER TO MID 60S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM WEDNESDAY...EXPECT SUMMER-LIKE WEATHER THROUGH THURS
AND FRI WITH UNSEASONABLY WARM TEMPERATURES AS BERMUDA HIGH
DOMINATES THE WEATHER. A BACKDOOR COLD FRONT WILL DROP DOWN INTO
NORTH CAROLINA AND MAY REACH FAR ENOUGH SOUTH TO PRODUCE MORE
VARIABLE WINDS EARLY THURS MORNING...BUT NOT EXPECTING THIS
FEATURE TO BE MUCH OF A PLAYER IN OUR OVERALL FORECAST. HIGH
PRESSURE OFF SHORE WILL DOMINATE...PRODUCING A DEEPER WARM AND
MOIST S-SW RETURN FLOW THROUGH THE LOW LEVELS OF THE
ATMOSPHERE...INCREASING INTO FRIDAY AS COLD FRONT APPROACHES THE
CAROLINAS FROM THE W-NW. THIS MORE SUMMER-LIKE MOIST AND MORE UNSTABLE
AIR MASS WILL HAVE THE POTENTIAL TO PRODUCE SOME LOCALIZED CLOUDS
AND CONVECTION ESPECIALLY AS MID TO UPPER RIDGE SLIPS OFF THE
COAST LATE THURS. THE SEA BREEZE WILL PENETRATE FAR ENOUGH INLAND
ON THURS TO KEEP MOST SHOWER ACTIVITY AWAY FROM THE COAST BUT THE
WESTERLY FLOW ALOFT SHOULD CARRY SOME OF THE DEBRIS CLOUDS
EASTWARD. WITH CLOUDS AND HIGH DEWPOINT AIR...TEMPS WILL REMAIN
WELL ABOVE NORMAL OVERNIGHT GIVING A JUMPSTART TO DAY TIME HIGHS
WHICH WILL REACH INTO THE 80S AND 70S CLOSER TO THE COAST.
DEEP MOIST SOUTHWESTERLY FLOW WILL INCREASE THROUGH FRIDAY AS
COLD FRONT APPROACHES FROM THE W-NW. THIS WILL INCREASE MOISTURE
THROUGH THE COLUMN WITH PCP WATER VALUES INCREASING UP CLOSE TO
1.75 INCHES BY FRI NIGHT IN DECENT LLJ. INITIALLY A STRONGER SEA
BREEZE SHOULD KEEP BEST CONVERGENCE AND CONVECTION AWAY FROM COAST
BUT AS STEERING FLOW VEERS AROUND WITH APPROACH OF FRONT...SHWRS
AND STORMS WILL REACH THE COAST. STRONGER CONVECTION IS LIKELY
AHEAD OF THE COLD FRONT...BUT THE BEST DYNAMICS ALOFT WILL REMAIN
NW OF FORECAST AREA AND THE COLD FRONT WILL COME THROUGH OVERNIGHT
AFTER BEST DIURNAL HEATING CUTS OFF. THEREFORE STRONGER CONVECTION
MAY REMAIN MORE ISOLATED. COLD FRONT SHOULD BE RIGHT AT THE COAST
BY SAT MORNING.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM WEDNESDAY...COLD FRONT RIGHT ALONG THE CAROLINA COAST
SATURDAY MORNING MAY GET HUNG UP BEFORE MAKING ITS WAY SOUTH LATER
IN THE DAY. THIS COULD LEAVE SOME LINGERING PCP ALONG THE COAST
THROUGH SAT MORNING BUT OVERALL EXPECT HIGH PRESSURE TO BUILD DOWN
BEHIND FRONT BRINGING A CHANGE OF AIR MASS TO THE CAROLINAS. PCP
WATER VALUES WILL DROP FROM CLOSE TO 1.75 INCHES AHEAD OF FRONT
DOWN CLOSE TO A HALF INCH BEHIND IT BY SAT AFTN. EXPECT WINDS TO
SHIFT AROUND TO A MORE NORTHERLY DIRECTION. COOLER AIR BEHIND
FRONT WILL BRING TEMPS BACK TO NORMAL SEASONABLE VALUES THROUGH
THE SECOND HALF OF THE WEEKEND INTO EARLY NEXT WEEK. GFS IS MORE
OPTIMISTIC WITH THE CLEARING BEHIND THE FRONT AND WILL HEDGE
TOWARD THIS SOLUTION WITH CLEARING THROUGH LATE SATURDAY AND SUNSHINE
FOR SUNDAY.
HIGH PRESSURE WILL SLIP OFF THE COAST MONDAY INTO TUES WITH A
DEEPER RETURN FLOW SETTING UP ONCE AGAIN. THIS WILL INTRODUCE POPS
BACK INTO THE FORECAST WITH A WARMER AND MORE UNSTABLE AIR MASS
RETURNING....BUT THE GFS KEEPS THE RIDGE FARTHER WEST AND
THEREFORE KEEPS BEST RETURN FLOW FARTHER INLAND. ALSO THE COOLER
OCEAN WATERS WILL KEEP A STRONGER SEA BREEZE THIS TIME OF YEAR AND
THEREFORE SHOULD PENETRATE FARTHER INLAND MON AND TUES KEEPING
BEST CHC OF PCP FARTHER INLAND. MAY END UP SUNNIER WEATHER BOTH
MON AND TUES FOR MOST OF THE FORECAST AREA.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...INTERMITTENT MVFR THIS MORNING WILL GIVE WAY TO VFR
OVER THE NEXT FEW HOURS AND CONTINUE THROUGH THE REST OF TODAY.
POTENTIAL FOR MVFR LATE OVERNIGHT INTO EARLY THURSDAY MORNING DUE
TO AREAS OF FOG AND LOW CIGS.
VFR PREVAILS ACROSS MOST OF THE FORECAST AREA THIS MORNING...WITH
THE EXCEPTION OF KLBT WHICH IS CURRENTLY OBSERVING MVFR CONDITIONS
DUE TO FOG. EXPECT OVER THE NEXT FEW HOURS FOR CONDITIONS TO
IMPROVE TO VFR ACROSS THE ENTIRE AREA...THOUGH WOULD NOT RULE OUT
A PASSING LIGHT SHOWER OR TWO. LIGHT WINDS THIS MORNING WILL
BECOME SOUTH-SOUTHWESTERLY...BACKING TO THE SOUTH THIS AFTERNOON
AOB 10 KTS WITH ISOLATED SHOWERS POSSIBLE ON THE AFTERNOON SEA
BREEZE. TONIGHT...VFR WILL PREVAIL WITH WINDS BECOMING LIGHT. MVFR
POSSIBLE DUE TO FOG AND PASSING LOW CIGS LATE OVERNIGHT INTO THE
EARLY MORNING HOURS ON THURSDAY.
EXTENDED OUTLOOK...CHANCE OF SHOWERS AND THUNDERSTORMS EACH DAY
AND BEST CHANCE FOR PRECIPITATION IS FRIDAY NIGHT INTO SATURDAY
MORNING. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 600 AM WEDNESDAY...A BACKDOOR COLD FRONT WILL SLOWLY SAG
SOUTH TOWARD THE AREA...REACHING JUST SOUTH OF THE VIRGINIA-NORTH
CAROLINA LINE BY THE END OF THE PERIOD. CIRCULATION AROUND
OFFSHORE HIGH PRESSURE WILL BE A LITTLE MORE WEST OF DUE SOUTH
THAN IN RECENT DAYS...BUT THE DIRECTION IS EXPECTED TO BACK
SLIGHTLY AS THE SEABREEZE BOUNDARY SHARPENS AND MOVES INLAND LATE
MORNING AND THIS AFTERNOON AND EXPECT WIND SPEEDS WILL BE ENHANCED
SLIGHTLY ACROSS THE NEAR SHORE WATERS DURING THIS TIME.
STILL...WILL NOT FORECAST SUSTAINED WINDS ANY HIGHER THAN 10 TO 15
KT WITH GUSTS AROUND 20 KT LIKELY. THE WIND DIRECTION WILL BE SW
TONIGHT. SOME NOCTURNAL JETTING MAY MIX DOWN ACROSS THE WARMER
OFFSHORE WATERS...BUT WITHIN 20 NM...EXPECT WIND SPEEDS WILL BE
CAPPED AT 15 KT. A SE SWELL ON THE ORDER OF 8 TO 9 SECONDS ALONG
WITH WIND ENERGY WILL HELP KEEP SEAS IN THE 3 TO 4 FT RANGE.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM WEDNESDAY...RETURN FLOW AROUND BERMUDA HIGH THURS
INTO FRIDAY WILL INCREASE ON FRIDAY AS COLD FRONT APPROACHES FROM
THE NORTHWEST. SEAS 2 TO 3 FT EXPECTED WITH S-SW WINDS OF 10 TO 15
KT WILL INCREASE THROUGH LATE FRI AHEAD OF FRONT...UP TO 3 TO 5 FT.
THE COOLER OCEAN WATERS COMPARED TO THE UNSEASONABLE WARM AIR
TEMPS EXPECTED OVER LAND WILL PRODUCE STRONGER SEA BREEZES CAUSING
A RISE IN BOTH WINDS AND SEAS WITH GUSTY NEAR SHORE WINDS.
INCREASING S WINDS AND ELEVATED DEWPOINTS LATE THURSDAY OVER THE
RELATIVELY COOLER INSHORE WATERS MAY PRODUCE PATCHY MARINE FOG
PRIMARILY THURSDAY NIGHT.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 330 AM WEDNESDAY...COLD FRONT APPROACHING FROM THE NORTHWEST WILL
REACH THE COAST SATURDAY MORNING AND SHOULD CROSS THE WATERS
THROUGH THE MORNING HOURS. SW WINDS AHEAD OF FRONT UP TO 10 TO 15
KT WILL SHIFT AROUND TO N THROUGH SAT MORNING. HIGH PRESSURE WILL
BUILD IN BEHIND COLD FRONT WITH WINDS VEERING SLIGHTLY THROUGH
SUNDAY AS THE HIGH SHIFTS FARTHER EAST TOWARD THE COAST WHILE
REMAINING NORTH OF LOCAL WATERS. SEAS UP TO 3 TO 5 FT AHEAD OF
FRONT EARLY SAT WILL SUBSIDE IN OFF SHORE TO NORTHERLY FLOW
THROUGH SAT AFTN DOWN TO 2 TO 4 FT BUT MAY SPIKE UP A LITTLE ON
SUNDAY IN PERSISTENT NE FLOW.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RJD
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...SGL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
650 AM EDT WED APR 8 2015
.SYNOPSIS...A MOIST AIR MASS AND SOUTHERLY FLOW WILL PERSIST OVER
THE REGION TODAY THROUGH TONIGHT. A BACKDOOR COLD FRONT WILL DROP
INTO NORTHEAST NORTH CAROLINA FROM THE NORTH LATE TONIGHT... THEN
LIFT BACK NORTH LATE THURSDAY. A COLD FRONT WILL APPROACH THE REGION
LATE FRIDAY.
&&
.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 315 AM WEDNESDAY...
TOUGH FORECAST THIS MORNING TRYING TO PINPOINT THE DETAILS OF
EXPECTED CONVECTION. LATEST SURFACE ANALYSIS SHOWS A PROMINENT COLD
FRONT FROM NRN OK THROUGH NRN MO... WITH A MORE DIFFUSE FRONTAL ZONE
EXTENDING ACROSS IL AND THE OH VALLEY THEN SOUTHEAST THROUGH NRN/ERN
VA. ISOLATED BUT STRONG AND ORGANIZED CONVECTION OVER SC INTO SE NC
EARLIER TONIGHT IS EXITING BUT ADDITIONAL LESS-ORGANIZED SHOWERS AND
ISOLATED STORMS ARE CLOSE BEHIND... THE DYING REMNANTS OF AN EARLIER
MATURE COMPLEX THAT CROSSED KY LAST EVENING. THIS HAS MANIFESTED
INTO A WEAK MCV THAT CAN BE DISCERNED IN RADAR AND WATER VAPOR
IMAGERY CENTERED OVER WEST CENTRAL VA. THE LAST FEW HRRR MODEL RUNS
REFLECTED BOTH OF THESE FEATURES BETTER THAN THE LARGER-SCALE MODELS
WITH PARAMETERIZED CONVECTION (NOT A SURPRISE)... AND HAVE LARGELY
FOLLOWED THIS SOLUTION FOR THE NEXT 12 HRS OR SO. EXPECT SCATTERED
SHOWERS AND A FEW STORMS THROUGH MID MORNING... WITH THE BEST CHANCE
SHIFTING TO NRN/ERN CWA NEAR AND SOON AFTER SUNRISE. WE SHOULD THEN
SEE A PERIOD OF RELATIVE SUBSIDENCE FROM ROUGHLY LATE MORNING
THROUGH MID AFTERNOON... AS THE VA MCV SHIFTS OFF THE COAST INDUCING
SURFACE LOW FORMATION ALONG THE WEAK FRONTAL ZONE. AS THIS OCCURS...
THE NORTHEAST FLOW ON THE BACKSIDE OF THIS LOW SHOULD HELP DRAW THE
FRONTAL ZONE SOUTHWARD INTO NORTH CENTRAL/NE NC. THE LAST SEVERAL
GFS RUNS HAVE TAKEN THIS FRONT MUCH FURTHER INTO NC THAN THE OTHER
MODEL SOLUTIONS. WHILE THERE IS A CHILLY SURFACE HIGH CENTERED OVER
QUEBEC NOSING SOUTHWARD OVER THE NORTHEAST STATES INTO THE NRN
MIDATLANTIC REGION... THIS LOOKS TO BE CENTERED TOO FAR NORTH TO
HAVE MUCH INFLUENCE ON THE FRONT THIS FAR SOUTH. EXPECT A WIND SHIFT
TO NORTHEASTERLY OVER THE NE CWA WITH SLIGHTLY COOLER TEMPS MOVING
IN LATE TODAY INTO TONIGHT... BUT THE COOLING SHOULDN`T BE THAT
EXTREME. WILL FORECAST HIGHS TODAY IN THE LOW-MID 80S EXCEPT FOR MID-
UPPER 70S IN THE FAR NE. ATTENTION THEN TURNS TO THE CONVECTION NOW
ALONG THE FRONT OVER KS/MO/IA/IL AND THE POTENTIAL FOR ITS RESULTING
MCV TO MOVE ESE ALONG THE FRONTAL ZONE INTO OUR REGION LATE TODAY
INTO TONIGHT. THE GFS HINTS AT THIS... SHOWING SPOTTY MID LEVEL
VORTICITY MAXIMA (LOOKING LIKE CONVECTIVE FEEDBACK) MOVING TO THE
CENTRAL/SRN APPALACHIANS LATE TODAY INTO TONIGHT. IT MAKES SENSE
THAT THIS WOULD TRIGGER CONVECTION ALONG AND EAST OF THE MOUNTAINS
WHERE MODELS INDICATE MUCAPE OF 1500-2500 J/KG IN THE 21Z-06Z TIME
FRAME WITH DEEP LAYER BULK SHEAR AROUND 30 KTS... STILL RATHER
MODEST BUT ENOUGH TO SUSTAIN CONVECTION AS THE COLD POOL TRACKS ESE
THROUGH NRN/ERN NC. WILL SHOW A PERIOD OF LOW POPS THROUGH MID
AFTERNOON... FOLLOWED BY A RISE TO SCATTERED SHOWERS/STORMS LATE
AFTERNOON THROUGH THIS EVENING... TRENDING DOWN OVERNIGHT AS THIS
PERTURBATION EXITS TO OUR EAST. WITH THE FRONT STILL EXPECTED TO BE
SITTING OVER THE NE CWA OVERNIGHT... WILL HAVE LOWS IN THE 60-65
RANGE EXCEPT FOR MID-UPPER 50S NE. -GIH
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM WEDNESDAY...
STRONG SURFACE LOW PRESSURE OVER THE CO/KS BORDER TODAY WILL REMAIN
STRONG AS TRACKS ALONG THE FRONT TO SRN WI LATE THU AND NEAR SAULT
STE MARIE BY DAYBREAK FRI. THE FRONTAL ZONE MEANWHILE BY LATE THU
WILL EXTEND ACROSS SRN MI DOWN THROUGH WRN PA/VA THEN EASTWARD ALONG
THE ERN VA/NC BORDER AREA. THE NAM/GFS SHOW DESTABILIZATION THU
AFTERNOON INTO EARLY EVENING (THE NAM MORESO THAN THE GFS)
ESPECIALLY OVER THE SW CWA SW OF THE FRONT WITH MUCAPE EXCEEDING
1500 J/KG... HOWEVER THE DEEP LAYER BULK SHEAR DECREASES TO LESS
THAN 25 KTS... A REFLECTION OF THE DIGGING ENERGY OVER THE MIDWEST
(LEADING TO THE STRONG SURFACE LOW) PROMPTING RISING HEIGHTS AND
REDUCED MID LEVEL WINDS OVER THE CAROLINAS/SOUTHEAST STATES... AND
THIS SHOULD REDUCE THE PROBABILITY FOR ANY STRONG TO SEVERE STORMS.
WILL BRING IN CHANCE POPS FOR SHOWERS AND STORMS... FOCUSED MAINLY
OVER THE NW HALF OF THE CWA... PEAKING DURING THE AFTERNOON INTO
EARLY EVENING. EXPECT HIGHS FROM THE MID 70S NE TO LOWER 80S SW.
WARM LOWS THU NIGHT IN THE MID 60S... WHICH WILL APPROACH RECORD
HIGH MINIMUMS FOR APRIL 10TH. -GIH
&&
LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 230 AM WEDNESDAY...
THERE IS GROWING CONFIDENCE WITH REGARD TO A FRONTAL SYSTEM THAT IS
PROGGED TO MOVE ACROSS THE CAROLINAS ON FRIDAY EVENING THROUGH
SATURDAY MORNING. THIS WILL BE FOLLOWED BY WEAK RIDGING ALOFT AND
SURFACE HIGH PRESSURE OVER THE MID ATLANTIC THROUGH THE WEEKEND.
CONFIDENCE IN THE FORECAST TAKES A BIG TURN FOR THE WORSE BEGINNING
ON MONDAY AS MODEL SOLUTIONS DIVERGE CONSIDERABLY. ABOUT THE ONLY
THING THEY AGREE ON AT THIS POINT IS SOME KIND OF UPPER RIDGING OVER
THE SOUTHEAST BUT EVEN THE POSITION AND TIMING OF THAT IS IN
QUESTION AT THIS TIME. THE PROBLEMS EARLY NEXT WEEK STEM FROM A
CUTOFF UPPER LEVEL LOW OVER TEXAS THAT FUNNELS MOISTURE OUT OF THE
GULF AND OVER THE DEEP SOUTH BUT THERE ARE MASSIVE QUESTIONS IN
TIMING AS THE ECMWF SOLUTION HAS PRECIPITATION REACHING CENTRAL NC
BY MONDAY AFTERNOON AND THE GFS DOESN`T HAVE ANYTHING MEASURABLE
OVER THE CWA UNTIL THURSDAY NIGHT. THAT QUALIFIES AS AN EXTREMELY
LOW CONFIDENCE FORECAST AND WILL BE HANDLED AS SUCH. THEREFORE WILL
MAINTAIN CHANCE POPS FROM MONDAY THROUGH THE END OF THE PERIOD.
SHIFTING THE CONVERSATION FROM WHAT WE DON`T KNOW TO MORE OF WHAT WE
DO KNOW REGARDING THE FRONTAL SYSTEM ON FRIDAY...SPC STILL HAS AN
AREA OF 15% RISK OF SEVERE STORMS OVER ALL OF CENTRAL NC. AFTER A
CLOSER LOOK AT THE FORECAST SOUNDINGS ON FRIDAY AFTERNOON...STORMS
WILL BE INSTABILITY DRIVEN WITH THE SOUTHEASTERN PART OF THE CWA
MOST LIKELY TO SEE STRONGER STORM ACTIVITY BUT THE POSSIBILITY WILL
REMAIN EVERYWHERE. THE KFAY MODEL SOUNDINGS SHOW JUST OVER 1100 J/KG
OF SURFACE BASED CAPE WITH 500 J/KG OCCURRING WITHIN THE HAIL GROWTH
ZONE. THE HAIL THREAT LOOKS BETTER THAN THE WIND THREAT AT THIS TIME
AS SHEAR IS MEAGER...ESPECIALLY IN THE LOW LEVELS. SOME INVERTED V
SIGNATURES IN THE SOUNDING AND SOME RELATIVE DRYING AT THE 700 MB
LEVEL COULD INCREASE THE POTENTIAL FOR SOME WET MICROBURSTS BUT
OVERALL THE ENVIRONMENT FOR WIND OUTSIDE OF A LARGER HAIL CORE
COLLAPSING IS LESS FAVORABLE AND VERY LOW AMOUNTS OF HELICITY
SUGGEST TORNADOES WILL NOT BE LIKELY EITHER. OVERALL FEELING IS THAT
SOME STRONGER STORMS WILL POP UP FRIDAY AFTERNOON BUT ANY SEVERE
WILL BE FAIRLY ISOLATED. WORTH WATCHING TO SEE HOW IT EVOLVES OVER
THE NEXT COUPLE OF DAYS. CONVECTION SHOULD PRODUCE DECENT QPF VALUES
IN THE RANGE OF A QUARTER TO THREE QUARTERS OF AN INCH. PW VALUES
ARE OVER AN INCH AND A HALF.
FRIDAY WILL BE THE WARMEST DAY AHEAD OF THE FRONT WITH HIGHS IN THE
MID 80S AND THEN TEMPS WILL COOL OFF AFTER THE FRONT PASSES WITH
HIGH PRESSURE BRINGING IN COOL AIR FROM THE NORTH. EXPECT MOSTLY LOW
TO MID 70S FOR HIGHS FOR THE REMAINDER OF THE PERIOD AFTER FRIDAY.
LOWS IN THE LOWER 50S TO MID 60S.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 650 AM WEDNESDAY...
PRIMARY AVIATION CONCERN NEXT 24 HRS: CHANCE OF MVFR OR IFR CIGS NOW
THROUGH MID MORNING... WITH A FEW SHOWERS AND POSSIBLE ISOLATED
STORMS.
CONFIDENCE IS LOWER THAN USUAL REGARDING THE FORECAST THROUGH THIS
MORNING. A VERY MOIST AIR MASS REMAINS IN PLACE FROM THE SURFACE UP
THROUGH THE MID LEVELS (ABOVE 15 000 FT). CIGS ARE EXPECTED TO BE
MAINLY IFR FOR ANOTHER FEW HOURS... BEFORE THEY RISE TO MVFR NEAR OR
SOON AFTER 13Z THEN TO VFR BY AROUND 16Z... HOWEVER AS THESE LOW
CLOUDS WILL VARY BETWEEN SCT AND BKN... FLIGHT CATEGORIES ARE LIKELY
TO WAVER AMONG MVFR... IFR... AND VFR THIS MORNING. AVIATORS SHOULD
REMAIN ALERT FOR THESE CHANGING CONDITIONS THIS MORNING. SCATTERED
SHOWERS WILL AFFECT RDU/RWI/FAY THROUGH 16Z... BUT VSBYS SHOULD GO
BE MAINLY MVFR IN THESE SHOWERS. AN ISOLATED STORM OR TWO IS
POSSIBLE... ESPECIALLY AT RDU/RWI BEFORE 14Z. THERE IS A HIGH
PROBABILITY OF VFR CONDITIONS FROM LATE MORNING THROUGH THE DAY...
WITH VERY FEW IF ANY SHOWERS/STORMS AS WE SHOULD BE IN A RELATIVE
LULL PERIOD BETWEEN CONVECTIVE SYSTEMS. A COUPLE OF MODELS HINT AT
MORE STORMS ROLLING OVER THE CENTRAL/SRN APPALACHIANS THIS EVENING
AND POTENTIALLY AFFECTING INT/GSO/RDU IN THE LAST 6-9 HRS OF THE TAF
VALID PERIOD WITH BRIEF SUB-VFR CIGS/VSBYS AND GUSTY WINDS...
HOWEVER CONFIDENCE IS NOT HIGH ENOUGH IN THE LOCATION AND TIMING OF
ANY SUCH SYSTEM TO INCLUDE IN THE TAFS AT THIS TIME. WILL CONTINUE
TO MONITOR. WE SHOULD SEE AREAS OF LOW CLOUDS AND FOG DEVELOP LATE
TONIGHT ESPECIALLY AFFECTING RDU/RWI AS A BACKDOOR FRONT DROPS
SOUTHWARD INTO THE NORTHEAST PORTION OF CENTRAL NC... WITH LIGHT
SURFACE WINDS SHIFTING AROUND TO NORTHEASTERLY.
LOOKING BEYOND 12Z EARLY THU MORNING... ANY LOW CLOUDS SHOULD LIFT
TO VFR THU MORNING... REMAINING VFR THROUGH THU EVENING WITH A FEW
SHOWERS/STORMS POSSIBLE THU AFTERNOON. AN APPROACHING COLD FRONT ON
FRIDAY WILL BRING A GOOD CHANCE OF SUB-VFR CONDITIONS WITHIN SHOWERS
AND STORMS FRI AFTERNOON AND EVENING. VFR CIGS/VSBYS ARE EXPECTED
BEHIND THE FRONT LATE FRI NIGHT THROUGH SUN AS HIGH PRESSURE BUILDS
IN. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...HARTFIELD
LONG TERM...ELLIS
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
620 AM EDT WED APR 8 2015
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTH INTO THE REGION LATE TODAY AND STALL
OVER THE AREA TONIGHT. THE FRONT WILL LIFT NORTH OF THE REGION
LATE THURSDAY. A COLD FRONT WILL APPROACH FROM THE WEST LATE
FRIDAY AND MOVE OFFSHORE SATURDAY MORNING. HIGH PRESSURE WILL
EXTEND OVER THE AREA FROM THE NORTH SATURDAY NIGHT AND SUNDAY. A
WARM FRONT WILL LIFT NORTH OF THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 620 AM WEDNESDAY...VERY DIFFICULT FORECAST NEXT 36 HOURS IN
TRYING TO PROVIDE DETAIL REGARDING PRECIPITATION CHANCES IN THE
MOIST BUT WEAKLY FORCED ATMOSPHERE OVER THE CAROLINAS. ZONAL FLOW
WILL CONTINUE ALBEIT WITH RIDGING AND ASSOCIATED SUBTLE HEIGHT
RISES OVER THE SOUTHEAST STATES THROUGH THURSDAY. WEAK LOW
AMPLITUDE MID LEVEL WAVES IN THIS FLOW WILL HAVE THE POTENTIAL TO
ENHANCE PRECIPITATION CHANCES ESPECIALLY IF THE ORGANIZED
CONVECTION EXPECTED OVER THE PLAINS TODAY TRIGGERS A STRONGER MCV
WHICH WOULD THEN MOVE EASTWARD TONIGHT. THE LARGE SCALE MODELS
HAVE BEEN HAVING A DIFFICULT TIME IN HANDLING THIS SITUATION SO
HAVE A RELIED ON THE HRRR AND THE HIGH RESOLUTION NMM AND WRF
MODELS TO TRY TO GET A BETTER HANDLE ON THIS.
2 MAIN AREAS OF PRECIPITATION OCCURRING EARLY THIS MORNING. ONE
ALONG THE IMMEDIATE COAST, ESPECIALLY THE ALBEMARLE SOUND REGION
AND NORTHERN OUTER BANKS, AND ANOTHER MOVING INTO THE COASTAL
PLAIN. THE HRRR MODEL BRINGS BOTH OF THESE AREAS ACROSS EASTERN
NC TODAY MAINLY THIS MORNING THEN INDICATES A LULL IN THE
PRECIPITATION THIS AFTERNOON AFTER 16Z. WILL BROADBRUSH THE
FORECAST WITH 30-40% POPS DUE TO INHERENT UNCERTAINTY ESPECIALLY
THIS AFTERNOON WHEN THE ATMOSPHERE BECOMES UNSTABLE AND A BACK
DOOR COLD FRONT BEGINS TO DROP SOUTH INTO NORTHERN PORTIONS OF THE
AREA DURING PEAK HEATING. TEMPERATURES WILL BE ABOVE NORMAL TODAY
IN THE SOUTHERLY PRE FRONTAL FLOW WITH HIGHS INLAND IN THE LOWER
80S AND LOWER 70S BEACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
AS OF 400 AM WEDNESDAY...THE BACK DOOR FRONT WILL SAG SOUTH TO
NEAR THE CRYSTAL COAST OVERNIGHT THEN STALL. STILL UNCERTAIN ON
PRECIPITATION DETAILS SO WILL FORECAST 30-50% POPS HIGHEST OUTER
BANKS. LOWS ARE FORECAST TO CONTINUE MILD WITH READINGS IN THE
UPPER 50S/LOWER 60S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 330 AM WEDNESDAY...00Z MODELS HAVE COME INTO BETTER
AGREEMENT WITH BACKDOOR FRONT STALLING OVER SRN SECTIONS LATE WED
NIGHT...THEN RETREATING NORTH ON THU. ECWMF AND GFS ALSO IN GOOD
AGREEMENT THAT STRONGER COLD FRONT WILL MOVE IN FRIDAY NIGHT AND
BE NEAR COAST SAT MORNING...THUS INCREASED POPS FRI NIGHT AND
DECREASED INLAND SAT.
THURSDAY AND THURSDAY NIGHT...SFC FRONT EXPECTED TO RETREAT NORTH
DURING THE DAY WITH WEAK RIDGING ALOFT. LACK OF UPR SUPPORT
EXPECTED TO LIMIT CONVECTIVE DEVELOPMENT BUT KEPT 20% POPS WITH
FRONT MOVING BACK NORTH. DID DROP POPS FOR THU NIGHT WITH MODELS
INDICATING PCPN THREAT WEST AND NORTH OF AREA. MOS GDNC CONTINUES
TO HAVE LARGE DIFFERENCES ON HIGH TEMPS WITH GFS COOLER AND NAM
WARMER DUE TO HANDLING OF FRONT. UPDATED PREVIOUS FCST WITH LEAN
TO COOLER GFS...HIGHS RANGING FROM AROUND 80 SOUTH TO 65-70 NORTH.
FRIDAY THROUGH SATURDAY...VERY WARM TEMPS EXPECTED FRIDAY AHEAD
OF A STRONGER COLD FRONT APPROACHING FRIDAY NIGHT. NO CHANGE TO
PREVIOUS THINKING FOR SHOWERS AND THUNDERSTORMS FRIDAY FOR INLAND
SECTIONS AS DECENT INSTABILITY AND UNIDIRECTIONAL WEST-SOUTHWEST
FLOW IS ENOUGH TO SUPPORT CHC POPS IN AFTERNOON INLAND OF SEA
BREEZE. LOW LEVEL THICKNESSES SUPPORT MID 80S FOR INLAND SECTIONS.
LATEST MODELS AGREE ON MAIN THREAT OF SHOWERS AND TSTMS ALONG AND
AHEAD OF COLD FRONT FRIDAY NIGHT...AND INCREASED POPS TO 60% ALL
ZONES...MAINLY FOR WRN HALF DURING EVENING AND ERN HALF OVERNIGHT.
CONCUR WITH SPC OUTLOOK OF SLIGHT RISK OF SVR WITH SUFFICIENT MID
LVL SHEAR TO SUPPORT ORGANIZED STRONG CONVECTION.
FRONT EXPECTED TO MOVE OFFSHORE SAT MORNING AND HAVE LOWERED POPS
TO INDICATE DRIER TREND. MAX TEMPS ABOUT 10 DEGS COOLER THAN
FRIDAY WITH MID 70S INLAND TO LOWER 60S NRN OBX.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...STRONG HIGH PRES WILL EXTEND
OVER AREA FROM NORTH SAT NIGHT AND SUNDAY AND GRADUALLY MOVE EAST
SUN NIGHT. DRY CONDITIONS EXPECTED WITH TEMPS NEAR NORMAL.
MONDAY INTO TUESDAY...NO CHANGE TO PREVIOUS FCST. HIGH PRES WILL
CONTINUE MOVING OFFSHORE WITH MOIST S TO SW FLOW RETURNING. SLIGHT
CHC POPS FOR SW HALF OF AREA MONDAY AND MON NIGHT...INCREASING TO
20-30% ALL AREAS TUESDAY. MAIN TEMP CHANGE WILL BE MIN TEMPS 10-15
DEGS ABOVE NORMAL MON NIGHT.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 620 AM WEDNESDAY...DIFFICULT FORECAST WITH CONVECTIVE
DEBRIS CLOUDS AND MIXING LIMITING RADIATIONAL COOLING AT TIMES
THIS MORNING...AND PRECIPITATION APPROACHING THE TAF SITES FROM
THE WEST. THE MOSTLY LIGHT PRECIPITATION WILL AFFECT THE TAF SITES
ON AND OFF THROUGH ABOUT 16Z WITH BRIEF MVFR CONDITIONS POSSIBLE
IN HEAVIER SHOWERS. THREAT NOT LOOKING AS WIDESPREAD AS EARLIER
AND SHOULD END BY 14Z. VFR CONDITIONS EXPECTED OUTSIDE OF
SCATTERED SHOWER/THUNDERSTORM ACTIVITY THROUGH THIS EVENING.
GUIDANCE IS AGAIN POINTING TO THE POTENTIAL FOR IFR CONDITIONS
REDEVELOPING AGAIN LATE THIS EVENING AS THE BL REMAINS SATURATED
BUT CONFIDENCE IN THIS LOW DUE TO RECENT TENDENCY FOR GUIDANCE TO
OVER FORECAST THESE CONDITIONS. LOW LEVEL EASTERLY FLOW BEHIND
THE BACK DOOR FRONT MAY BE MORE CONDUCIVE TO IFR CONDITIONS THOUGH
SO WILL HAVE TO CONTINUE TO MONITOR.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 400 AM WEDNESDAY...SOME LOWER CIGS COULD PERSIST THURS
MORNING WITH LOW LEVEL NE FLOW. VFR MAINLY EXPECTED THURS NIGHT
INTO FRIDAY...THEN HIGHER THREAT OF SUB-VFR CONDITIONS FRI NIGHT
INTO EARLY SAT WITH GOOD COVERAGE OF SHOWERS AND TSTMS EXPECTED
AS STRONGER FRONT MOVES INTO AREA. GUSTY SW WINDS 15-25 MPH LIKELY
FRIDAY AHEAD OF FRONT. HIGH PRESSURE WILL ALLOW AVIATION
CONDITIONS TO IMPROVE TO VFR SATURDAY EVENING THROUGH SUNDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 620 AM WEDNESDAY...WINDS WILL REMAIN 15 KT OR LESS THROUGH
TONIGHT. THE MAIN FEATURE WILL BE A BACK DOOR COLD FRONT WHICH IS
FORECAST TO PUSH SOUTH INTO THE NORTHERN WATERS/ALBEMARLE SOUND
TODAY THEN CONTINUE SOUTH TONIGHT INTO THE CENTRAL WATERS/PAMLICO
SOUND WHERE IT WILL STALL. EXPECT WINDS TO VEER FROM SOUTHERLY
THIS MORNING TO SOUTHWEST TO WEST BY THIS AFTERNOON THEN TO NORTH
AND NORTHEAST BEHIND THE FRONT LATER TODAY AND TONIGHT. SEAS WILL
REMAIN IN THE 2-4 FT RANGE THROUGH THE PERIOD.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 400 AM WEDNESDAY...CONTINUED PREVIOUS FCST THINKING WITH
WINDS GRADUALLY RETURNING TO S-SW DURING THE DAY THU AS FRONT
RETREATS BACK NORTH. MAIN CHANGE WAS TO INDICATE FASTER COLD FRONT
PASSAGE SAT MORNING WITH LATEST MODELS IN GOOD AGREEMENT. STILL
EXPECT STRONGEST WINDS FRI AND FRI NIGHT AHEAD OF FRONT...SW
15-25 KT WITH SEAS BUILDING TO SMALL CRAFT ADVISORY LEVELS FRI
AFTN INTO EARLY SAT. NE SURGE 10-20 KT EXPECTED LATE SAT THROUGH
SUNDAY. ADJUSTED SEAS WITH LATEST NWPS. HEIGHTS MAINLY 3-4 FT
THU...BUILDING TO 4-6 FT FRI-FRI NIGHT...THEN DIMINISHING 2-4 FT
SUNDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JME
NEAR TERM...JME
SHORT TERM...JME
LONG TERM...JBM
AVIATION...JME/JBM
MARINE...JME/JBM
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1150 AM EDT WED APR 8 2015
.SYNOPSIS...
A QUASI-STATIONARY FRONT WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PENNSYLVANIA TODAY THROUGH THURSDAY. A COLD FRONT
WILL MOVE THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...ADJUSTED TEMPS AGAIN BASED ON HRRR. POPS DECENT BUT
TRIMMED BACK THE FOG TO THE WEST.
ORIGINAL...THE SHOWER ACTIVITY FROM OVERNIGHT HAS DECREASED AS
EXPECTED. SHOWERS AND A FEW THUNDERSTORMS ARE FORMING TO THE WEST
AND THIS SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED TO INCREASE
LATE THIS MORNING AND INTO THE AFTERNOON. PATCHY DENSE FOG HAS
FORMED IN MANY LOCATIONS THIS MORNING...INCLUDING REPORTS IN NW
PA. I WILL EXPAND THE MENTION OF PATCHY DENSE FOG TO ALMOST ALL
AREAS FOR THE NEXT FEW HOURS. MINOR ADJUSTMENTS TO TEMPERATURES
AND PRECIPITATION TO REFLECT THE CURRENT TRENDS.
PREVIOUS DISCUSSION...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PA TODAY. LITTLE MOVEMENT IS EXPECTED WITH THE FRONT
WHICH IS TYPICAL FOR THIS TIME OF YEAR AS THESE TYPE OF STATIONARY
FRONTS SET UP ON THE SOUTH SHORE OF LAKE ERIE. SHOWERS ARE EXPECTED
NEAR THE FRONTAL BOUNDARY TODAY BUT I DO NOT EXPECT WIDE SPREAD
AREAL COVERAGE. IT WILL BE TOUGH TO PREDICT THE TIMING. LOCALIZED
BOUNDARIES AND DAYTIME HEATING WILL MOST LIKELY TRIGGER THE SHOWERS.
THIS IS RE-ENFORCED BY THE HRRR MODEL AS SEVERAL RUNS INDICATED
SCATTERED/ISOLATED SHOWER PATTERN OVER THE REGION THROUGH THE DAY.
I WILL KEEP HIGH CHANCE TO LOW LIKELY RANGED POPS OVER THE AREA.
THUNDER IS POSSIBLE AND THE THREAT WILL INCREASE THIS AFTERNOON.
THE STORM PREDICTION CENTER HAS PLACED SOME OF THE NORTHWEST AND
NORTH CENTRAL OHIO IN A SLIGHT RISK CATEGORY FOR SEVERE
THUNDERSTORMS TODAY. BIG TEMPERATURE GRADIENT AGAIN NORTH TO SOUTH
ACROSS THE AREA. NORTHEAST FLOW NEAR THE LAKE WILL KEEP
TEMPERATURES MUCH COOLER
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER THE FORECAST AREA
WEDNESDAY NIGHT INTO THURSDAY. WITH THE LACK OF STRONG DYNAMICS
EARLY IN THE PERIOD...THE SHOWERS WILL ONCE AGAIN BE DIFFICULT TO
TIME. SHOWERS AND A FEW THUNDERSTORMS WILL REMAIN OVER THE AREA BUT
IT WILL BE FAIRLY UNORGANIZED. AS THE SHORT WAVE IN ADVANCE OF THE
COLD FRONT BEGINS TO MOVE TOWARDS THE AREA THURSDAY...THE STATIONARY
FRONT WILL MOVE NORTHWARD AS A WARM FRONT AND THE UPPER LEVEL
SUPPORT WILL BECOME MORE FOCUSED. A LARGE AREA OF Q-VECTOR
CONVERGENCE IS NOTED THURSDAY NIGHT WITH THE UPPER LEVEL SYSTEM.
THE SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH MORE NUMEROUS
AND ORGANIZED ON THURSDAY NIGHT AND SEVERE WEATHER THREAT IS STILL A
QUESTION. THE TIMING IS NOT OPTIMAL AS THE BEST LIFT WILL OCCUR
DURING THE OVERNIGHT HOURS. WE WILL STILL CONTINUE TO MONITOR THE
THREAT. AT THIS TIME MOST OF THE FORECAST AREA HAS A MARGINAL RISK
FOR SEVERE THUNDERSTORMS THURSDAY NIGHT.
THE COLD FRONT WILL SWEEP ACROSS THE REGION ON FRIDAY. A FEW
SHOWERS AND A POSSIBLE THUNDERSTORM MAY LINGER OVER THE EASTERN
SECTIONS OF THE AREA FRIDAY MORNING BUT SHOWER ACTIVITY SHOULD
RAPIDLY DECREASE IN THE AFTERNOON. DRY AIR AND COLD ADVECTION WILL
OCCUR FRIDAY NIGHT. 850MB TEMPS AS LOW AS -8C COULD MOVE OVER THE
LAKE FRIDAY NIGHT INTO EARLY SATURDAY. A FEW WET SNOW FLAKES ARE
NOT OUT OF THE QUESTION FOR NE OH AND NW PA BUT I WILL LEAVE THE
MENTION OF SNOW OUT OF THE FORECAST AT THIS TIME. THE AIR IS VERY
DRY BEHIND THE FRONT AND IT MAY BE DIFFICULT TO GET ANY TYPE OF
PRECIPITATION WITHOUT ASSISTANCE FROM THE LAKE. HIGH PRESSURE WILL
BUILD OVER THE REGION LATE SATURDAY THROUGH SATURDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE OVER THE AREA SHOULD PROVIDE DRY CONDITIONS ON SUN
AND ALLOW TEMPS TO MODERATE BACK A FEW DEGREES ABOVE NORMAL. THE DRY
CONDITIONS WILL QUICKLY CHANGE GOING INTO SUN NIGHT AS RETURN FLOW
MOISTURE ARRIVES ALONG WITH A WEAK COLD FRONT FROM THE WEST. WILL
GENERALLY LEAVE SUN NIGHT FORECAST AS IS BUT ALLOW FOR A MORE
UNIFORM PRECIP THREAT ON MON. MODELS TRYING TO SHOW A REPEAT SETUP
OF THE CURRENT PATTERN WITH A FRONT STALLED NEAR THE AREA STARTING
BY TUE AND LASTING ALL WEEK SO WILL INCREASE POPS A LITTLE MORE.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
WEST TO EAST LYING FRONT NEAR MFD WILL DRIFT SLOWLY NORTH TO THE
SOUTH SHORE OF LAKE ERIE THIS AFTERNOON AND THEN WAVER SOME BEFORE
HEADING OFF TO THE NORTH INTO FRI MORNING. GUIDANCE INDICATES
IMPROVEMENT TO MVFR/LOW VFR LATE MORNING INTO MIDDAY SO WILL PLAY
TAFS THAT WAY. SCT SHRA WILL AFFECT THE AREA THRU THE PERIOD. BETTER
THREAT FOR TSRA THIS AFTERNOON AND TONIGHT AS AIRMASS BECOMES MORE
UNSTABLE...BUT WHERE AND WHEN TSRA MAY OCCUR IS ANYBODY`S GUESS SO
FOR NOW WILL KEEP OUT OF TAFS OTHER THAN MENTION WITH VCTS.
CONDITIONS EXPECTED TO LOWER AGAIN BY LATE EVENING AS LOW LEVELS
COOL A FEW DEGREES.
.OUTLOOK...NON VFR SHOULD IMPROVE WEST TO EAST ON FRI WITH PASSAGE
OF COLD FRONT BUT AREAS OF NON VFR MAY HANG AROUND SNOWBELT INTO
EARLY SATURDAY.
&&
.MARINE...
WILL LEAVE SCA FOR WEST PART OF THE LAKE GOING UNTIL 3 PM BUT COULD
BE TAKEN DOWN SOONER IF FRONT LIFTS INTO NEARSHORE WATERS A LITTLE
BEFORE THEN AND TURNS WINDS MORE SOUTH AT A DIMINISHED SPEED. MODELS
INDICATE THE FRONT MAY SAG BACK SOUTH OF THE LAKE TOWARD
EVENING...POSSIBLY DUE TO LAKE BREEZE ENHANCEMENT BUT THEN SHOULD
START TO LIFT BACK INTO THE LAKE LATER IN THE NIGHT AND CONTINUE OFF
TO THE NORTH ON THU. THE WARM AIR FLOWING OVER THE COLD LAKE SHOULD
PROVIDE A STABILIZING EFFECT SO WILL CONTINUE TO KEEP WINDS UNDER 20
KTS UNTIL THU NIGHT WHEN LOW LEVEL FLOW INCREASES MORE AND STARTS TO
TURN SW. THIS WILL PROVIDE MORE FAVORABLE CONDITIONS FOR WINDS TO
INCREASE TO AT LEAST 15 TO 25 KNOTS.
THE PASSAGE OF THE COLD FRONT LATE THU NIGHT AND FRI MORNING WILL
TURN THE WINDS TO THE WEST AND AS COLDER AIR MOVES IN CAN SEE WINDS
AROUND 30 KNOTS SO WILL INCREASE THE FORECAST. HIGH PRESSURE SLOWLY
PUSHES INTO OH TO GRADUALLY DIMINISH THE WINDS FRI NIGHT THRU SAT SO
THE SCA WILL END. NOT SURE IF THE ICE IS BROKEN UP ENOUGH OR NOT BUT
THIS MAY BE THE EVENT WHERE THE ICE TYPICALLY GETS PUSHED INTO THE
EAST END OF THE LAKE WITH THE STRONGER SW TO W WINDS.
THE HIGH WILL SHIFT OFF THE MID ATLANTIC COAST BY SUN NIGHT TO ALLOW
LIGHT WINDS TO TURN SE AND START TO INCREASE SOME.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
LEZ142>146.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET/TK
SHORT TERM...GARNET
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1038 AM EDT WED APR 8 2015
.SYNOPSIS...
A WARM AND MOIST SOUTH TO SOUTHWEST WIND FLOW WILL BRING ROUNDS OF
SHOWERS AND THUNDERSTORMS THROUGHOUT THE WEEK. COLD FRONT CROSSES AT
THE END OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
1025 AM UPDATE...THE 12Z HRRR HAS FINALLY LATCHED ON TO CONVECTION
COMING ACROSS INDIANA...UP TO THIS POINT EVERYTHING TRIED TO KEEP
ACTIVITY WELL TO OUR NORTH...BUT THE RECENT HRRR AND NEW 12Z NAM
AS ITS JUST ROLLING IN ARE MUCH MORE BELIEVABLE ROLLING A LINE OF
CONVECTION ACROSS SOUTHERN OHIO LATE THIS MORNING INTO THIS
AFTERNOON. RELIED VERY HEAVILY ON THE 12Z HRRR TO UPDATE POPS.
THINGS MAY BE SPEEDING UP JUST A TOUCH...SO MAY NEED TO ADJUST
TIMING AGAIN IN A COUPLE HOURS AS THINGS APPROACH. DECENT
LINE...ALTHOUGH HAVE NOT SEEN ANY SEVERE LEVEL LSRS OUT OF
UPSTREAM OFFICES...BUT EXPECT AT LEAST SOME RISK OF SEVERE LEVEL
WINDS AS THIS LINE CONTINUES TOWARD US. HAVE COORDINATED A SEVERE
THUNDERSTORM WATCH INTO OUR WESTERN COUNTIES.
PREVIOUS DISCUSSION...
MESO NAM SHOWS A BOUNDARY MOVING INTO THE FORECAST AREA THIS
AFTERNOON PRODUCING SHOWERS AND THUNDERSTORMS. TRACING THIS BOUNDARY
BACK TO THE CURRENT TIME...IT MATCHES WELL WITH CONVECTION OVER
MISSOURI AND IOWA. THEREFORE...WILL CONTINUE WITH LIKELY POPS
PROPAGATING WEST TO EAST DURING THE AFTERNOON HOURS. WITH THIS BAND
HITTING DURING THE AFTERNOON HOURS...AM A BIT CONCERNED ABOUT THE
POTENTIAL FOR FLOODING. HOWEVER...NAM IS SHOWING THE BAND
ORIENTATION IS PERPENDICULAR TO THE STORM MOVEMENT WITH A DECENT 15
KNOT MOVEMENT. IN ADDITION...PRECIPITABLE WATER IS NOT THAT HIGH.
THEREFORE...WILL HOLD OFF ON A WATCH FOR NOW AND CONTINUE TO
HIGHLIGHT IN THE HWO.
NAM HAS ANOTHER DISTURBANCE MOVING OVER TONIGHT THAT IS NOT
REFLECTED IN THE GFS. THIS BAND ORIGINATES FROM A VORTICITY LOBE
DURING CONVECTION THIS AFTERNOON. THAT LEADS TO A LOWER
CONFIDENCE...SO WILL BE FAIRLY GENERIC WITH POPS.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/...
WARMEST DAY OF THE WEEK STILL SHAPING UP FOR WEDNESDAY. STILL TRICKY
FORECASTING HIGHS AS AREA WILL BE BATTLING SHRA/TSRA
CHANCES...ESPECIALLY EARLY AND ACROSS SE OH AND N WV. WILL ROLL A
MIDDLE GROUND SOLUTION WITH LOW 80S...PRIMARILY ACROSS S ZONES. IT
WILL BE BREEZY AMID STRENGTHENING S FLOW. CANT RULE OUT A FEW SHRA
AND TSRA IN THE AFTERNOON. SOME OF THESE STORMS COULD BE STRONG TO
SVR...ESPECIALLY ACROSS SE OH.
A BREEZY AND WARM NIGHT THURSDAY NIGHT WITH THE COLD FRONT MAKING AN
APPROACH ON OUR WESTERN FLANK AFTER MIDNIGHT. MODELS CONTINUE TO
SPEED UP THE FRONT...NOW BLOWING IT THRU BY MIDDAY FRIDAY. SO...HAVE
THE BOUNDARY CROSSING THE OH RIVER 12Z FRIDAY AND C WV 15Z...EXITING
THE MOUNTAINS BY 18Z. WILL HAVE SOME FRONTAL SHRA/TSRA TO CONTEND
WITH...SOME OF WHICH COULD BE STRONG TO LOW END SVR AS HIGHLIGHTED
BY SPC CONVECTIVE OUTLOOK.
CLEARING WILL TAKE PLACE IN THE FRESHENING POSTFRONTAL AIRMASS
FRIDAY NIGHT. THIS WILL TAKE US INTO WHAT WILL BE A STELLAR
WEEKEND...WITH MILD DAYTIME TEMPS AND A PARTLY CLOUDY SKY. TI WILL
CHILL OFF PRETTY GOOD SATURDAY NIGHT WITH HIGH PRESSURE OVERHEAD
WITH A FROST CONCERN FOR THE LOWLANDS.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
MODELS ARE QUICKER WITH THE COLD FRONTAL PASSAGE ON FRIDAY LEAVING
FRIDAY NIGHT MOSTLY DRY. THE OUTLIER IS THE ECMWF WHICH LAGS ABOUT 6
HOURS IN ITS QPF FIELD. WENT WITH THE CONSENSUS OF MODELS WITH A
FASTER SOLUTIONS.
HIGH PRESSURE BRINGS WIDESPREAD DRY WEATHER FRIDAY NIGHT THROUGH THE
WEEKEND. ANOTHER UPPER WAVE APPROACHES MONDAY BRINGING BACK CHANCES
FOR PCPN ACROSS THE AREA.
TEMPERATURES EXPECTED TO BE WARM REACHING THE UPPER 70S THROUGH THE
PERIOD...EXCEPT FOR A SLIGHT COOL DOWN BEHIND THE COLD FRONT
SATURDAY...GENERALLY IN THE MID TO UPPER 60S. WENT CLOSE TO WPC
GUIDANCE WITH FEW TWEAKS THROUGH THE PERIOD.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
A STRATUS DECK ACROSS THE AREA THIS MORNING HAS SOME HOLES THAT HAVE
ALLOWED PATCHY FOG. AFTER ANY MORNING FOG BURNS OFF THIS
MORNING...EXPECT THE STRATUS DECK TO CHANGE INTO A CUMULUS
DECK...GRADUALLY RISING DURING THE DAY. AN AREA OF SHOWERS AND
THUNDERSTORMS IS EXPECTED THIS AFTERNOON...BEGINNING FIRST IN
SOUTHEAST OHIO AND NORTHEASTERN KY...THEN PUSHING EASTWARD. BRIEF
IFR RESTRICTIONS ARE POSSIBLE WITH THE STRONG CELLS.
CLOUDS SHOULD GENERALLY BE VFR WEDNESDAY EVENING...BUT DEPENDING ON
SKY COVER...SOME PATCHES OF FOG COULD ALSO FORM. SHOWERS AND
THUNDERSTORMS WILL REMAIN A POSSIBILITY TONIGHT. THE HEIGHT OF ANY
CLOUD DECKS LATE TONIGHT IS HARD TO FORECAST...AS MOISTURE AT MOST
LEVELS COULD FORM A CLOUD DECK.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z THURSDAY...
FORECAST CONFIDENCE: MEDIUM TODAY...LOW TONIGHT.
ALTERNATE SCENARIOS: TIMING AND DENSITY OF FOG THIS MORNING AND
TONIGHT COULD VARY. STRONGER STORMS THIS AFTERNOON COULD CAUSE BRIEF
IFR CONDITIONS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY M H M H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H M H H H H H H H
EKN CONSISTENCY M H H H H H H H H H H H
PKB CONSISTENCY H H H M M M H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z THURSDAY...
BRIEF IFR POSSIBLE IN SHOWERS AND/OR THUNDERSTORMS THROUGH FRIDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/RPY/30
NEAR TERM...RPY/MZ
SHORT TERM...30
LONG TERM...ARJ
AVIATION...RPY
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
941 AM EDT WED APR 8 2015
.SYNOPSIS...
A QUASI-STATIONARY FRONT WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PENNSYLVANIA TODAY THROUGH THURSDAY. A COLD FRONT
WILL MOVE THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...ADJUSTED TEMPS BASED ON HRRR. ALSO ADJUSTED POPS. TRIED
TO TIME CURRENT CONVECTION EAST ACROSS THE AREA BASED ON
EXTRAPOLATION AND HRRR GUIDANCE.
ORIGINAL...THE SHOWER ACTIVITY FROM OVERNIGHT HAS DECREASED AS
EXPECTED. SHOWERS AND A FEW THUNDERSTORMS ARE FORMING TO THE WEST
AND THIS SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED TO INCREASE
LATE THIS MORNING AND INTO THE AFTERNOON. PATCHY DENSE FOG HAS
FORMED IN MANY LOCATIONS THIS MORNING...INCLUDING REPORTS IN NW
PA. I WILL EXPAND THE MENTION OF PATCHY DENSE FOG TO ALMOST ALL
AREAS FOR THE NEXT FEW HOURS. MINOR ADJUSTMENTS TO TEMPERATURES
AND PRECIPITATION TO REFLECT THE CURRENT TRENDS.
PREVIOUS DISCUSSION...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PA TODAY. LITTLE MOVEMENT IS EXPECTED WITH THE FRONT
WHICH IS TYPICAL FOR THIS TIME OF YEAR AS THESE TYPE OF STATIONARY
FRONTS SET UP ON THE SOUTH SHORE OF LAKE ERIE. SHOWERS ARE EXPECTED
NEAR THE FRONTAL BOUNDARY TODAY BUT I DO NOT EXPECT WIDE SPREAD
AREAL COVERAGE. IT WILL BE TOUGH TO PREDICT THE TIMING. LOCALIZED
BOUNDARIES AND DAYTIME HEATING WILL MOST LIKELY TRIGGER THE SHOWERS.
THIS IS RE-ENFORCED BY THE HRRR MODEL AS SEVERAL RUNS INDICATED
SCATTERED/ISOLATED SHOWER PATTERN OVER THE REGION THROUGH THE DAY.
I WILL KEEP HIGH CHANCE TO LOW LIKELY RANGED POPS OVER THE AREA.
THUNDER IS POSSIBLE AND THE THREAT WILL INCREASE THIS AFTERNOON.
THE STORM PREDICTION CENTER HAS PLACED SOME OF THE NORTHWEST AND
NORTH CENTRAL OHIO IN A SLIGHT RISK CATEGORY FOR SEVERE
THUNDERSTORMS TODAY. BIG TEMPERATURE GRADIENT AGAIN NORTH TO SOUTH
ACROSS THE AREA. NORTHEAST FLOW NEAR THE LAKE WILL KEEP
TEMPERATURES MUCH COOLER
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER THE FORECAST AREA
WEDNESDAY NIGHT INTO THURSDAY. WITH THE LACK OF STRONG DYNAMICS
EARLY IN THE PERIOD...THE SHOWERS WILL ONCE AGAIN BE DIFFICULT TO
TIME. SHOWERS AND A FEW THUNDERSTORMS WILL REMAIN OVER THE AREA BUT
IT WILL BE FAIRLY UNORGANIZED. AS THE SHORT WAVE IN ADVANCE OF THE
COLD FRONT BEGINS TO MOVE TOWARDS THE AREA THURSDAY...THE STATIONARY
FRONT WILL MOVE NORTHWARD AS A WARM FRONT AND THE UPPER LEVEL
SUPPORT WILL BECOME MORE FOCUSED. A LARGE AREA OF Q-VECTOR
CONVERGENCE IS NOTED THURSDAY NIGHT WITH THE UPPER LEVEL SYSTEM.
THE SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH MORE NUMEROUS
AND ORGANIZED ON THURSDAY NIGHT AND SEVERE WEATHER THREAT IS STILL A
QUESTION. THE TIMING IS NOT OPTIMAL AS THE BEST LIFT WILL OCCUR
DURING THE OVERNIGHT HOURS. WE WILL STILL CONTINUE TO MONITOR THE
THREAT. AT THIS TIME MOST OF THE FORECAST AREA HAS A MARGINAL RISK
FOR SEVERE THUNDERSTORMS THURSDAY NIGHT.
THE COLD FRONT WILL SWEEP ACROSS THE REGION ON FRIDAY. A FEW
SHOWERS AND A POSSIBLE THUNDERSTORM MAY LINGER OVER THE EASTERN
SECTIONS OF THE AREA FRIDAY MORNING BUT SHOWER ACTIVITY SHOULD
RAPIDLY DECREASE IN THE AFTERNOON. DRY AIR AND COLD ADVECTION WILL
OCCUR FRIDAY NIGHT. 850MB TEMPS AS LOW AS -8C COULD MOVE OVER THE
LAKE FRIDAY NIGHT INTO EARLY SATURDAY. A FEW WET SNOW FLAKES ARE
NOT OUT OF THE QUESTION FOR NE OH AND NW PA BUT I WILL LEAVE THE
MENTION OF SNOW OUT OF THE FORECAST AT THIS TIME. THE AIR IS VERY
DRY BEHIND THE FRONT AND IT MAY BE DIFFICULT TO GET ANY TYPE OF
PRECIPITATION WITHOUT ASSISTANCE FROM THE LAKE. HIGH PRESSURE WILL
BUILD OVER THE REGION LATE SATURDAY THROUGH SATURDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE OVER THE AREA SHOULD PROVIDE DRY CONDITIONS ON SUN
AND ALLOW TEMPS TO MODERATE BACK A FEW DEGREES ABOVE NORMAL. THE DRY
CONDITIONS WILL QUICKLY CHANGE GOING INTO SUN NIGHT AS RETURN FLOW
MOISTURE ARRIVES ALONG WITH A WEAK COLD FRONT FROM THE WEST. WILL
GENERALLY LEAVE SUN NIGHT FORECAST AS IS BUT ALLOW FOR A MORE
UNIFORM PRECIP THREAT ON MON. MODELS TRYING TO SHOW A REPEAT SETUP
OF THE CURRENT PATTERN WITH A FRONT STALLED NEAR THE AREA STARTING
BY TUE AND LASTING ALL WEEK SO WILL INCREASE POPS A LITTLE MORE.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
WEST TO EAST LYING FRONT NEAR MFD WILL DRIFT SLOWLY NORTH TO THE
SOUTH SHORE OF LAKE ERIE THIS AFTERNOON AND THEN WAVER SOME BEFORE
HEADING OFF TO THE NORTH INTO FRI MORNING. GUIDANCE INDICATES
IMPROVEMENT TO MVFR/LOW VFR LATE MORNING INTO MIDDAY SO WILL PLAY
TAFS THAT WAY. SCT SHRA WILL AFFECT THE AREA THRU THE PERIOD. BETTER
THREAT FOR TSRA THIS AFTERNOON AND TONIGHT AS AIRMASS BECOMES MORE
UNSTABLE...BUT WHERE AND WHEN TSRA MAY OCCUR IS ANYBODY`S GUESS SO
FOR NOW WILL KEEP OUT OF TAFS OTHER THAN MENTION WITH VCTS.
CONDITIONS EXPECTED TO LOWER AGAIN BY LATE EVENING AS LOW LEVELS
COOL A FEW DEGREES.
.OUTLOOK...NON VFR SHOULD IMPROVE WEST TO EAST ON FRI WITH PASSAGE
OF COLD FRONT BUT AREAS OF NON VFR MAY HANG AROUND SNOWBELT INTO
EARLY SATURDAY.
&&
.MARINE...
WILL LEAVE SCA FOR WEST PART OF THE LAKE GOING UNTIL 3 PM BUT COULD
BE TAKEN DOWN SOONER IF FRONT LIFTS INTO NEARSHORE WATERS A LITTLE
BEFORE THEN AND TURNS WINDS MORE SOUTH AT A DIMINISHED SPEED. MODELS
INDICATE THE FRONT MAY SAG BACK SOUTH OF THE LAKE TOWARD
EVENING...POSSIBLY DUE TO LAKE BREEZE ENHANCEMENT BUT THEN SHOULD
START TO LIFT BACK INTO THE LAKE LATER IN THE NIGHT AND CONTINUE OFF
TO THE NORTH ON THU. THE WARM AIR FLOWING OVER THE COLD LAKE SHOULD
PROVIDE A STABILIZING EFFECT SO WILL CONTINUE TO KEEP WINDS UNDER 20
KTS UNTIL THU NIGHT WHEN LOW LEVEL FLOW INCREASES MORE AND STARTS TO
TURN SW. THIS WILL PROVIDE MORE FAVORABLE CONDITIONS FOR WINDS TO
INCREASE TO AT LEAST 15 TO 25 KNOTS.
THE PASSAGE OF THE COLD FRONT LATE THU NIGHT AND FRI MORNING WILL
TURN THE WINDS TO THE WEST AND AS COLDER AIR MOVES IN CAN SEE WINDS
AROUND 30 KNOTS SO WILL INCREASE THE FORECAST. HIGH PRESSURE SLOWLY
PUSHES INTO OH TO GRADUALLY DIMINISH THE WINDS FRI NIGHT THRU SAT SO
THE SCA WILL END. NOT SURE IF THE ICE IS BROKEN UP ENOUGH OR NOT BUT
THIS MAY BE THE EVENT WHERE THE ICE TYPICALLY GETS PUSHED INTO THE
EAST END OF THE LAKE WITH THE STRONGER SW TO W WINDS.
THE HIGH WILL SHIFT OFF THE MID ATLANTIC COAST BY SUN NIGHT TO ALLOW
LIGHT WINDS TO TURN SE AND START TO INCREASE SOME.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
LEZ142>146.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET/TK
SHORT TERM...GARNET
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
702 AM EDT WED APR 8 2015
.SYNOPSIS...
A QUASI-STATIONARY FRONT WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PENNSYLVANIA TODAY THROUGH THURSDAY. A COLD FRONT
WILL MOVE THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE SHOWER ACTIVITY FROM OVERNIGHT HAS DECREASED AS EXPECTED.
SHOWERS AND A FEW THUNDERSTORMS ARE FORMING TO THE WEST AND THIS
SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED TO INCREASE LATE THIS
MORNING AND INTO THE AFTERNOON. PATCHY DENSE FOG HAS FORMED IN
MANY LOCATIONS THIS MORNING...INCLUDING REPORTS IN NW PA. I WILL
EXPAND THE MENTION OF PATCHY DENSE FOG TO ALMOST ALL AREAS FOR THE
NEXT FEW HOURS. MINOR ADJUSTMENTS TO TEMPERATURES AND PRECIPITATION
TO REFLECT THE CURRENT TRENDS.
PREVIOUS DISCUSSION...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PA TODAY. LITTLE MOVEMENT IS EXPECTED WITH THE FRONT
WHICH IS TYPICAL FOR THIS TIME OF YEAR AS THESE TYPE OF STATIONARY
FRONTS SET UP ON THE SOUTH SHORE OF LAKE ERIE. SHOWERS ARE EXPECTED
NEAR THE FRONTAL BOUNDARY TODAY BUT I DO NOT EXPECT WIDE SPREAD
AREAL COVERAGE. IT WILL BE TOUGH TO PREDICT THE TIMING. LOCALIZED
BOUNDARIES AND DAYTIME HEATING WILL MOST LIKELY TRIGGER THE SHOWERS.
THIS IS RE-ENFORCED BY THE HRRR MODEL AS SEVERAL RUNS INDICATED
SCATTERED/ISOLATED SHOWER PATTERN OVER THE REGION THROUGH THE DAY.
I WILL KEEP HIGH CHANCE TO LOW LIKELY RANGED POPS OVER THE AREA.
THUNDER IS POSSIBLE AND THE THREAT WILL INCREASE THIS AFTERNOON.
THE STORM PREDICTION CENTER HAS PLACED SOME OF THE NORTHWEST AND
NORTH CENTRAL OHIO IN A SLIGHT RISK CATEGORY FOR SEVERE
THUNDERSTORMS TODAY. BIG TEMPERATURE GRADIENT AGAIN NORTH TO SOUTH
ACROSS THE AREA. NORTHEAST FLOW NEAR THE LAKE WILL KEEP
TEMPERATURES MUCH COOLER
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER THE FORECAST AREA
WEDNESDAY NIGHT INTO THURSDAY. WITH THE LACK OF STRONG DYNAMICS
EARLY IN THE PERIOD...THE SHOWERS WILL ONCE AGAIN BE DIFFICULT TO
TIME. SHOWERS AND A FEW THUNDERSTORMS WILL REMAIN OVER THE AREA BUT
IT WILL BE FAIRLY UNORGANIZED. AS THE SHORT WAVE IN ADVANCE OF THE
COLD FRONT BEGINS TO MOVE TOWARDS THE AREA THURSDAY...THE STATIONARY
FRONT WILL MOVE NORTHWARD AS A WARM FRONT AND THE UPPER LEVEL
SUPPORT WILL BECOME MORE FOCUSED. A LARGE AREA OF Q-VECTOR
CONVERGENCE IS NOTED THURSDAY NIGHT WITH THE UPPER LEVEL SYSTEM.
THE SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH MORE NUMEROUS
AND ORGANIZED ON THURSDAY NIGHT AND SEVERE WEATHER THREAT IS STILL A
QUESTION. THE TIMING IS NOT OPTIMAL AS THE BEST LIFT WILL OCCUR
DURING THE OVERNIGHT HOURS. WE WILL STILL CONTINUE TO MONITOR THE
THREAT. AT THIS TIME MOST OF THE FORECAST AREA HAS A MARGINAL RISK
FOR SEVERE THUNDERSTORMS THURSDAY NIGHT.
THE COLD FRONT WILL SWEEP ACROSS THE REGION ON FRIDAY. A FEW
SHOWERS AND A POSSIBLE THUNDERSTORM MAY LINGER OVER THE EASTERN
SECTIONS OF THE AREA FRIDAY MORNING BUT SHOWER ACTIVITY SHOULD
RAPIDLY DECREASE IN THE AFTERNOON. DRY AIR AND COLD ADVECTION WILL
OCCUR FRIDAY NIGHT. 850MB TEMPS AS LOW AS -8C COULD MOVE OVER THE
LAKE FRIDAY NIGHT INTO EARLY SATURDAY. A FEW WET SNOW FLAKES ARE
NOT OUT OF THE QUESTION FOR NE OH AND NW PA BUT I WILL LEAVE THE
MENTION OF SNOW OUT OF THE FORECAST AT THIS TIME. THE AIR IS VERY
DRY BEHIND THE FRONT AND IT MAY BE DIFFICULT TO GET ANY TYPE OF
PRECIPITATION WITHOUT ASSISTANCE FROM THE LAKE. HIGH PRESSURE WILL
BUILD OVER THE REGION LATE SATURDAY THROUGH SATURDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE OVER THE AREA SHOULD PROVIDE DRY CONDITIONS ON SUN
AND ALLOW TEMPS TO MODERATE BACK A FEW DEGREES ABOVE NORMAL. THE DRY
CONDITIONS WILL QUICKLY CHANGE GOING INTO SUN NIGHT AS RETURN FLOW
MOISTURE ARRIVES ALONG WITH A WEAK COLD FRONT FROM THE WEST. WILL
GENERALLY LEAVE SUN NIGHT FORECAST AS IS BUT ALLOW FOR A MORE
UNIFORM PRECIP THREAT ON MON. MODELS TRYING TO SHOW A REPEAT SETUP
OF THE CURRENT PATTERN WITH A FRONT STALLED NEAR THE AREA STARTING
BY TUE AND LASTING ALL WEEK SO WILL INCREASE POPS A LITTLE MORE.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
WEST TO EAST LYING FRONT NEAR MFD WILL DRIFT SLOWLY NORTH TO THE
SOUTH SHORE OF LAKE ERIE THIS AFTERNOON AND THEN WAVER SOME BEFORE
HEADING OFF TO THE NORTH INTO FRI MORNING. GUIDANCE INDICATES
IMPROVEMENT TO MVFR/LOW VFR LATE MORNING INTO MIDDAY SO WILL PLAY
TAFS THAT WAY. SCT SHRA WILL AFFECT THE AREA THRU THE PERIOD. BETTER
THREAT FOR TSRA THIS AFTERNOON AND TONIGHT AS AIRMASS BECOMES MORE
UNSTABLE...BUT WHERE AND WHEN TSRA MAY OCCUR IS ANYBODY`S GUESS SO
FOR NOW WILL KEEP OUT OF TAFS OTHER THAN MENTION WITH VCTS.
CONDITIONS EXPECTED TO LOWER AGAIN BY LATE EVENING AS LOW LEVELS
COOL A FEW DEGREES.
.OUTLOOK...NON VFR SHOULD IMPROVE WEST TO EAST ON FRI WITH PASSAGE
OF COLD FRONT BUT AREAS OF NON VFR MAY HANG AROUND SNOWBELT INTO
EARLY SATURDAY.
&&
.MARINE...
WILL LEAVE SCA FOR WEST PART OF THE LAKE GOING UNTIL 3 PM BUT COULD
BE TAKEN DOWN SOONER IF FRONT LIFTS INTO NEARSHORE WATERS A LITTLE
BEFORE THEN AND TURNS WINDS MORE SOUTH AT A DIMINISHED SPEED. MODELS
INDICATE THE FRONT MAY SAG BACK SOUTH OF THE LAKE TOWARD
EVENING...POSSIBLY DUE TO LAKE BREEZE ENHANCEMENT BUT THEN SHOULD
START TO LIFT BACK INTO THE LAKE LATER IN THE NIGHT AND CONTINUE OFF
TO THE NORTH ON THU. THE WARM AIR FLOWING OVER THE COLD LAKE SHOULD
PROVIDE A STABILIZING EFFECT SO WILL CONTINUE TO KEEP WINDS UNDER 20
KTS UNTIL THU NIGHT WHEN LOW LEVEL FLOW INCREASES MORE AND STARTS TO
TURN SW. THIS WILL PROVIDE MORE FAVORABLE CONDITIONS FOR WINDS TO
INCREASE TO AT LEAST 15 TO 25 KNOTS.
THE PASSAGE OF THE COLD FRONT LATE THU NIGHT AND FRI MORNING WILL
TURN THE WINDS TO THE WEST AND AS COLDER AIR MOVES IN CAN SEE WINDS
AROUND 30 KNOTS SO WILL INCREASE THE FORECAST. HIGH PRESSURE SLOWLY
PUSHES INTO OH TO GRADUALLY DIMINISH THE WINDS FRI NIGHT THRU SAT SO
THE SCA WILL END. NOT SURE IF THE ICE IS BROKEN UP ENOUGH OR NOT BUT
THIS MAY BE THE EVENT WHERE THE ICE TYPICALLY GETS PUSHED INTO THE
EAST END OF THE LAKE WITH THE STRONGER SW TO W WINDS.
THE HIGH WILL SHIFT OFF THE MID ATLANTIC COAST BY SUN NIGHT TO ALLOW
LIGHT WINDS TO TURN SE AND START TO INCREASE SOME.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
LEZ142>146.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET
SHORT TERM...GARNET
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS NORMAN OK
648 AM CDT WED APR 8 2015
.DISCUSSION...
THE 12Z AVIATION DISCUSSION FOLLOWS....
&&
.AVIATION...
A STATIONARY FRONT VERY NEAR THE OK/KS BORDER MAY SAG A LITTLE
FARTHER S THIS MORNING...BEFORE MOVING N AS A WARM FRONT LATER
TODAY. IF IT MOVES S OF KGAG/KWWR/KPNC EARLY THIS MORNING...LOW
CLOUDS AND BR/FG COULD MOVE INTO THOSE SITES...BUT SHOULD BE
SHORT-LIVED. TSRA MAY FORM THIS MORNING...MOST LIKELY ALONG
I-44...AND ARE EXPECTED TO BE ELEVATED IN NATURE...SO NOT LIKELY
SEVERE. MUCH MORE ROBUST TSRA...POSSIBLY WITH SEVERE
WEATHER...OUTFLOW...AND OTHER TYPICAL AVIATION HAZARDS...WILL
DEVELOP AROUND MID-AFTERNOON THROUGH THIS EVENING IF THE LOW-LEVEL
INVERSION CAN BE OVERCOME. THIS IS MOST LIKELY TO HAPPEN AT
KPNC...BUT IS ALSO POSSIBLE AT ALL OTHER TAF SITES. TSRA SHOULD
BECOME MORE NUMEROUS...BUT LESS SEVERE...OVERNIGHT AS THE DRYLINE
AND A COLD FRONT BEGIN TO ADVANCE E. LOW CEILINGS ARE LIKELY
TOMORROW MORNING IN ADVANCE OF THE DRYLINE/FRONT COMBINATION.
CMS
&&
.PREV DISCUSSION... /ISSUED 424 AM CDT WED APR 8 2015/
DISCUSSION...
AN APPROACHING UPPER-LEVEL WAVE MAY GENERATE A FEW
SHOWERS/THUNDERSTORMS THIS MORNING OR EARLY AFTERNOON OVER NORTH
TEXAS AND OKLAHOMA. THESE SHOWERS/STORMS WOULD BE ELEVATED...AND
WOULD POSE LITTLE OR NO RISK OF PRODUCING SEVERE WEATHER.
THE RISK OF SEVERE WEATHER LATER THIS AFTERNOON AND THIS EVENING
CONTINUES TO BE PROBLEMATIC...AS A RATHER STRONG CAPPING INVERSION
WILL REDUCE THE ABILITY OF STORMS TO DEVELOP IN AN OTHERWISE
FAVORABLE ENVIRONMENT FOR SEVERE WEATHER. WE CONTINUE WITH
RELATIVELY LOW PROBABILITIES OF RAIN...BUT IT IS STILL THE CASE
THAT ANY STORM OR STORMS THAT DO FORM WILL HAVE PLENTY OF
INSTABILITY AND SHEAR TO WORK WITH. THE PRESENCE OF A DRYLINE AND
STATIONARY FRONT WILL LIKELY OVERCOME THE CAP...AT LEAST NEAR THE
KANSAS BORDER...THIS AFTERNOON. THAT CONVECTION WILL LIKELY
GENERATE NEW CONVECTION AS OUTFLOW BOUNDARIES PROVIDE SUFFICIENT
LOW-LEVEL CONVERGENCE TO OVERCOME THE WEAKER PARTS OF THE CAP.
STORMS THAT DEVELOP WILL LIKELY PERSIST INTO THE NIGHT.
STORMS WILL CONTINUE OFF AND ON INTO TOMORROW AFTERNOON...AND AN
APPARENTLY SLOWER MOVEMENT OF THE COLD FRONT WILL KEEP RAIN
CHANCES IN OUR SOUTHEAST COUNTIES THROUGH EARLY FRIDAY. IN
ADDITION TO THE SLOWNESS...IT APPEARS THAT THE FRONT WILL NOT GO
VERY FAR SOUTH...AND RETURN MOISTURE WILL BRING RAIN CHANCES BACK
INTO OUR SOUTHERN COUNTIES FRIDAY EVENING...ELIMINATING THE ONLY
DAY THAT HAD BEEN FORECAST TO BE COMPLETELY RAIN-FREE BETWEEN NOW
AND THE EARLY PART OF NEXT WEEK.
SHOWERS AND STORMS WILL PROBABLY BECOME FAIRLY NUMEROUS OVER THE
WEEKEND...THEN DIMINISH SLOWLY IN PROBABILITY INTO EARLY NEXT
WEEK.
ALSO PROBLEMATIC TODAY IS THE WILDFIRE POTENTIAL FOR THIS
AFTERNOON AND THIS EVENING. ALL MODELS SHOW THE DRYLINE FARTHER
WEST THAN BEFORE...AND NONE OF THEM SUPPORT A RED FLAG WARNING
OUTSIDE THE NEW WARNING AREA...GENERALLY WEST OF A LINE FROM
WOODWARD TO SAYRE. THE HRRR DOES SHOW THE DRYLINE FARTHER EAST
THAN THIS...BUT DOES NOT HAVE SUFFICIENT WIND SPEEDS OUTSIDE THIS
AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 82 63 78 49 / 20 30 10 10
HOBART OK 87 61 78 46 / 20 20 10 10
WICHITA FALLS TX 85 66 84 51 / 20 30 10 10
GAGE OK 92 53 71 39 / 10 10 0 0
PONCA CITY OK 81 60 74 44 / 40 30 10 10
DURANT OK 80 66 77 53 / 20 30 30 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS
EVENING FOR OKZ004-009-010-014-021.
TX...NONE.
&&
$$
09/23/23
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
758 AM EDT WED APR 8 2015
.SYNOPSIS...
A NEARLY STATIONARY FRONT JUST SOUTH OF PENNSYLVANIA WILL COMBINE
WITH STRONG HIGH PRESSURE OVER QUEBEC CANADA...TO KEEP MOIST AND
COOL CONDITIONS OVER THE REGION THROUGH THURSDAY WITH PERIODS OF
RAIN AND DRIZZLE...AND A GENERALLY LIGHT EAST TO NORTHEAST WIND.
DEEPENING LOW PRESSURE MOVING NORTHEAST ACROSS THE UPPER GREAT
LAKES THURSDAY NIGHT WILL PUSH ITS TRAILING COLD FRONT ACROSS
PENNSYLVANIA DURING THE MIDDAY AND AFTERNOON HOURS FRIDAY. MUCH
COOLER CONDITIONS WILL FOLLOW FOR SATURDAY...WITH EVEN A FEW SNOW
SHOWERS POSSIBLE ACROSS THE NORTHWEST MOUNTAINS SATURDAY MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE EARLIER LULL IN THE RAIN SHOWERS IS COMING TO AN END AS A
COMPACT AND QUITE FLAT UPPER SHORT WAVE SLIDES EAST OF THE
PENN/OHIO BORDER.
WEAK LLVL RIDGING THROUGH THE SUSQ VALLEY AND SCENT MTNS WILL
CONTINUE THE RELATIVE MIN IN SHOWERS THERE FOR THE NEXT 1-2 HOURS.
05Z HRRR WAS BLENDED IN TO POPULATE NEAR TERM POPS/WEATHER AND QPF
GRIDS THROUGH THIS AFTERNOON. THIS DATA SHOWS A STEADY PROGRESSION
OF SHOWERS ACROSS CENTRAL PENN DURING THE MID TO LATER MORNING
HOURS...FOLLOWED BY A DISTINCT LULL IN THE PRECIP THIS AFTERNOON
WITH WIDESPREAD STRATUS REMAINING AND JUST A FEW ISOLATED SHOWERS
OR SOME PATCHY DRIZZLE POSSIBLE.
CONSIDERING THE TIGHT TEMP/DWPT SPREAD OF GENERALLY 1-2 DEG F
ACROSS THE CENTRAL AND WESTERN ZONES...TEMPS ARE RIGHT NEAR THEIR
MINS. A SLIGHTLY GREATER T/TD SPREAD ACROSS THE SUSQ VALLEY WILL
ALLOW FOR A 2-4 DEG F TEMP DROP BETWEEN 10-12Z AS THE INCREASING
COVERAGE OF SHOWERS SPREADS EWD INTO THAT AREA.
HIGH TEMPS THIS AFTERNOON WILL BE MUCH COOLER THAN
TUESDAY...RANGING FROM AROUND 40 DEG ACROSS THE HIGHER TERRAIN OF
THE WRN POCONOS AND ENDLESS MTNS NW OF KIPT...TO THE MID 50S ON
THE WRN SIDE OF THE ATLANTIC/GOMEX WATER SHED BOUNDARY /NEAR THE
RT 219 CORRIDOR/.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
CLOUDY...COOL AND DAMP CONDITIONS WILL CONTINUE TONIGHT AS HIGH
PRESSURE OVER QUEBEC CANADA RIDGES SWWD INTO THE STATE ACCOMPANIED
BY A LIGHT EAST TO NE BREEZE. AT THE SAME TIME...MEAN TEMPS IN
THE 900-850 MB LAYER WILL INCREASE BY ABOUT 2-3 DEG C /BETWEEN
00Z-12Z THU/. THIS SHOULD LEAD TO RIDGE SHROUDING FOG ACROSS MUCH
OF THE REGION WITH THE LOWEST VSBYS ON THE EAST-FACING UPPER
SLOPES.
ANOTHER FLAT SHORTWAVE /OR MCV FROM WEAKENING UPSTREAM TSRA/
APPEARS TO MOVE EAST FROM THE OHIO VALLEY AND TARGET MUCH OF THE
REGION OVERNIGHT TONIGHT. CAN/T RULE OUT A FEW TSRA ACROSS OUR
WESTERN ZONES LATE TODAY/THIS EVENING...NEAR THE EASTERN EDGE OF
WEAK-MDT LEVELS OF MLCAPE OF 500-1000 J/KG. ELSEWHERE...A FEW
SHOWERS WILL BE LIKELY WITH BASIN AVG RAINFALL AMOUNTS AROUND 0.10
OF AN INCH /PERHAPS A FEW TENTHS HIGHER THOUGH ACROSS THE LAURELS
- CLOSER TO THE WEAKENING TSRA/.
TEMPS TONIGHT COULD DIP OR STAY 3-5F COOLER THAN MOST GUIDANCE AS
VERY SHALLOW AND ANOMALOUSLY COOL NEAR SFC AIR WILL BE FUNNELED
SWWD FROM THE NEW ENGLAND STATES AND HUDSON VALLEY. APPROX 03Z
SREF GUIDANCE WAS USED FOR TONIGHT/S MINS...WHICH SUPPORT A LOW
PROBABILITY FOR -FZRA/-FZDZ ACROSS THE WRN POCONOS AND ENDLESS
MTNS REGION NE OF KIPT. LOWS TONIGHT RANGE FROM THE LOWER 30S
ACROSS THE ERN HIGH TERRAIN...TO THE MID AND UPPER 40S WEST OF RT
219 IN WRN PENN.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
WARMER AIR WILL WORK INTO THE AREA LATE THU INTO FRIDAY...AS LOW
LEVEL WIND FIELDS INCREASE. WARMEST TEMPERATURES MIGHT END UP
BEING ACROSS WARREN COUNTY.
DID NOT UP TEMPS MUCH FOR FRIDAY...MODELS MOVE COLD FRONT ACROSS
THE AREA RATHER FAST.
SOME CHANCE OF A STRONG THUNDERSTORM ACROSS THE WEST LATER FRIDAY.
THIS BASED ON TIMING AND THE THERMAL RIDGE OVER THE BEST MOISTURE.
HAVE TO WATCH FOR SEVERE...BUT DYNAMICS LIKELY TO LIFT NE AWAY
FROM THE AREA. ALSO TIMING NOT THE BEST.
WHILE WE WILL SEE SOME SHOWERS EACH DAY THIS WEEK...NOT SEEING ANY
LARGE AMTS. THUS NOT SEEING ANY WIDESPREAD HYDRO CONCERNS AT THIS
POINT. ENJOY THE MILDER TEMPERATURES.
RATHER STRONG SMALL UPPER LEVEL TROUGH FOR LATE FRIDAY INTO SAT.
TOOK OUT SHOWERS AFTER EARLY FRIDAY EVENING. MAIN THING WAS TO
LOWER TEMPS FOR FRIDAY NIGHT INTO SAT...GIVEN AIRMASS TO THE NORTH
AND COLD ADVECTION.
WEEKEND SIMILAR TO LAST WEEKEND. BREEZY AND COOL ON SAT. WARMER
ON SUNDAY.
DID PUT SOME SHOWERS IN THE FAR WEST LATE MONDAY AND ACROSS THE
AREA ON TUE. MODELS SHOW ANOTHER COLD FRONT MOVING IN.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
SHORTWAVE SLIDING OVERHEAD THIS MORNING GENERATING AN AREA OF
SHOWERS THAT WILL CONTINUE TO PROGRESS ACROSS CENTRAL
PA...REACHING THE LOWER SUSQ AROUND 14Z. THESE WILL END FROM THE
WEST BY MID MORNING IN THE NORTHERN/CENTRAL MTNS AND BY 18Z IN THE
LOWER SUSQ...WITH JUST SOME DRIZZLE LIKELY THIS AFT. WIDESPREAD
IFR CIG RESTRICTIONS ONGOING WILL PERSIST FOR MUCH OF THE DAY AND
THROUGH TONIGHT...THOUGH COULD SEE CIGS LIFT ABOVE 1000FT IN THE
EAST FOR SEVERAL HOURS THIS AFT. VSBYS VARIABLE...BUT MOVING FROM
GENERALLY MVFR TO MORE WIDESPREAD VFR LATER THIS MORNING.
STATIONARY FRONTAL BOUNDARY OFF TO OUR SW WILL KEEP LOW LEVEL
MOISTURE LOCKED IN PLACE TONIGHT...AS CONDITIONS SETTLE BACK INTO
WIDESPREAD IFR. AREAS OF DRIZZLE WILL BE AROUND...WITH RAIN
SLIPPING INTO WESTERN SECTIONS OVERNIGHT.
WINDS WILL REMAIN FROM THE EAST AT 5-10 MPH THROUGH THE PERIOD.
OUTLOOK...
WED...WIDESPREAD MVFR/IFR IN SHRA/PERIODS OF RA.
THU...REDUCTIONS LIKELY IN SCT SHRA.
FRI...REDUCTIONS LIKELY IN SHRA...ESPECIALLY DURING THE
AFT. CHC OF THUNDER AFT.
SAT-SUN...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/MARTIN
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1014 AM CDT WED APR 8 2015
.DISCUSSION...
SKIES ARE MOSTLY SUNNY OVER MUCH OF THE FORECAST AREA THIS MORNING
WITH TEMPERATURES IN THE 70S. SOME ISOLATED SHOWERS CONTINUE TO
MOVE OVER NORTHERN SECTIONS OF THE FORECAST AREA BUT THIS ACTIVITY
IS JUST ABOUT DONE. SOME ISOLATED THUNDERSTORMS MAY MOVE THROUGH
NORTHERN SECTIONS OF THE FORECAST AREA THIS AFTERNOON. WILL SEND
AN UPDATE TO THE FORECAST TO REMOVE MORNING WORDING.
ARS
&&
.PREV DISCUSSION... /ISSUED 608 AM CDT WED APR 8 2015/
AS OF 4AM...TEMPERATURES ARE MILD ONCE AGAIN THIS MORNING WITH
READINGS MAINLY IN THE MID TO UPPER 60S ACROSS THE REGION. EARLIER
CONVECTION NEAR THE SOUTHERN KANSAS/MISSOURI BORDER HAS WEAKENED
SIGNIFICANTLY IN THE LAST COUPLE OF HOURS WITH ONLY LIGHT SHOWERS
DEVELOPING TO THE SOUTH OF THE LEFTOVER COMPLEX. A BROAD AREA OF
SCATTERED SHOWERS AND THUNDERSTORMS WERE MOVING OVER PORTIONS OF
CENTRAL AND NORTHEAST ARKANSAS ASSOCIATED WITH A WEAK SHORTWAVE
EMBEDDED IN THE MEAN FLOW. WATER VAPOR IMAGERY ALSO SHOWS A LARGE
CUTOFF LOW ROTATING OVER THE GREAT BASIN THIS MORNING. THIS
FEATURE WILL BE MAIN WEATHER MAKER ACROSS OUR AREA OVER THE NEXT
48 HOURS OR SO.
SHORT TERM...TODAY THROUGH FRIDAY...
THE HRRR HI-RES SHORT TERM MODEL INDICATES THAT SHOWERS AND
SCATTERED THUNDERSTORMS WILL MOVE THROUGH THE MID-SOUTH AGAIN
THIS MORNING. COVERAGE IS EXPECTED TO LESS THAN YESTERDAY...BUT
WILL STILL WARRANT A 20 POP. BY EARLY AFTERNOON...SHOWERS WILL
EXIT THE AREA AND SLIGHT UPPER LEVEL RIDGING WILL RESULT IN
CLEARING SKIES AND VERY WARM CONDITIONS FOR THIS TIME OF YEAR.
READINGS WILL BE IN THE LOW TO MID 80S THIS AFTERNOON...WHICH IS
AS MUCH AS 15 DEGREES ABOVE THE CLIMATOLOGICAL NORMAL FOR THIS
TIME OF YEAR AND NEAR RECORD HIGHS.
BY LATE TONIGHT...MODELS ARE IN REASONABLE AGREEMENT THAT THE
UPPER LEVEL CLOSED LOW OUT WEST WILL EVOLVE INTO AN OPEN WAVE AS
IT MOVES ACROSS THE ROCKIES...AND SURFACE LOW PRESSURE WILL
DEVELOP NEAR THE OKLAHOMA PANHANDLE. THIS SURFACE LOW WILL MOVE
ACROSS THE CENTRAL PLAINS AND INTO THE GREAT LAKES REGION FROM
THURSDAY MORNING AND INTO FRIDAY. AS IT DOES...A STRONG COLD FRONT
WILL SWEEP ACROSS THE MISSISSIPPI VALLEY AND INTERACT WITH A
MODERATELY UNSTABLE AIRMASS. MLCAPE VALUES APPROACHING 2000 J/KG
AND A 50 KT MID LEVEL JET WILL SUPPORT AT LEAST A FEW STRONG TO
SEVERE STORMS. STORM MODE IS STILL A LITTLE UNCLEAR AT THE
MOMENT...BUT IT DOES APPEAR SOME STORMS COULD DEVELOP AHEAD OF THE
LINE AS HEIGHT FALLS OVERSPREAD THE REGION...BEFORE CONGEALING
INTO A QLCS STRUCTURE BY LATE THURSDAY EVENING. DAMAGING WINDS AND
LARGE HAIL LOOK TO BE THE MAIN THREATS...WITH A SECONDARY THREAT
OF FLASH FLOODING. TORNADO THREAT LOOKS VERY MINIMAL...AS THE
FAVORABLE JET STRUCTURE REMAINS WELL TO OUR NORTH. WILL CONTINUE
TO MAKE A MENTION OF SEVERE STORMS IN THE HWO WITH THE BEST
CHANCES REMAINING OVER NORTHEAST ARKANSAS...THE MISSOURI
BOOTHEEL...AND PORTIONS OF NORTHWEST TENNESSEE.
BY FRIDAY AFTERNOON...THE FRONT WILL PUSH TO THE SOUTH AND EAST
AS SURFACE HIGH PRESSURE BUILDS IN. TEMPERATURES WILL BE MILD
DURING THE DAY WITH UPPER 60S AND LOWER 70S EXPECTED.
SATURDAY WILL BE A BEAUTIFUL MILD SPRING DAY WITH LOW HUMIDITY...
TEMPERATURES IN THE LOWER 70...AND ABUNDANT SUNSHINE.
LONG TERM...SUNDAY THROUGH EARLY NEXT WEEK...
A STALLED COLD FRONT TO OUR SOUTH WILL PUSH NORTH AS A WARM FRONT
ON SUNDAY MORNING. AS IT DOES...SHOWERS AND THUNDERSTORMS WILL
OVERSPREAD THE REGION BY THE AFTERNOON HOURS. SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO CONTINUE ON MONDAY BEFORE A COLD
FRONT PUSHES THROUGH THE MID-SOUTH BY TUESDAY. CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO MIDWEEK AS RETURN FLOW
REMAINS DOMINANT ACROSS THE REGION.
AC3
&&
.AVIATION...
12Z TAF CYCLE (08/12Z-09/12Z)
IFR CONDITIONS IN FOG WILL OCCUR AT KTUP UNTIL 13Z...OTHERWISE
MVFR CONDITIONS ARE POSSIBLE AT THE TAF SITES THROUGH 14Z.
MENTIONED VCTS AT KJBR UNTIL 14Z WITH PATCHY LIGHT RAIN AFFECTING
KMEM...KMKL...AND KJBR UNTIL 14Z. VFR CONDITIONS ARE EXPECTED
AFTER 14Z THROUGH THE REMAINDER OF THE PERIOD.
WINDS TODAY AT KMEM...KMKL...AND KJBR INCREASING FROM THE
SW AT 12-18 KTS WITH GUSTS 20-27 KTS. WINDS TODAY AT KTUP BECOMING
SW 12 KTS. WINDS TONIGHT AT KMEM...KMKL AND KJBR S 8-13 KTS
BECOMING AT KJBR AFTER 09/07Z S 15 KTS WITH GUSTS 22 KTS. WINDS
TONIGHT AT KTUP S 6-8 KTS.
JCL
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
608 AM CDT WED APR 8 2015
.UPDATE...
UPDATED TO INCLUDE THE 12Z AVIATION DISCUSSION BELOW.
JCL
&&
.DISCUSSION... /ISSUED 434 AM CDT WED APR 8 2015/
AS OF 4AM...TEMPERATURES ARE MILD ONCE AGAIN THIS MORNING WITH
READINGS MAINLY IN THE MID TO UPPER 60S ACROSS THE REGION. EARLIER
CONVECTION NEAR THE SOUTHERN KANSAS/MISSOURI BORDER HAS WEAKENED
SIGNIFICANTLY IN THE LAST COUPLE OF HOURS WITH ONLY LIGHT SHOWERS
DEVELOPING TO THE SOUTH OF THE LEFTOVER COMPLEX. A BROAD AREA OF
SCATTERED SHOWERS AND THUNDERSTORMS WERE MOVING OVER PORTIONS OF
CENTRAL AND NORTHEAST ARKANSAS ASSOCIATED WITH A WEAK SHORTWAVE
EMBEDDED IN THE MEAN FLOW. WATER VAPOR IMAGERY ALSO SHOWS A LARGE
CUTOFF LOW ROTATING OVER THE GREAT BASIN THIS MORNING. THIS
FEATURE WILL BE MAIN WEATHER MAKER ACROSS OUR AREA OVER THE NEXT
48 HOURS OR SO.
SHORT TERM...TODAY THROUGH FRIDAY...
THE HRRR HI-RES SHORT TERM MODEL INDICATES THAT SHOWERS AND
SCATTERED THUNDERSTORMS WILL MOVE THROUGH THE MID-SOUTH AGAIN
THIS MORNING. COVERAGE IS EXPECTED TO LESS THAN YESTERDAY...BUT
WILL STILL WARRANT A 20 POP. BY EARLY AFTERNOON...SHOWERS WILL
EXIT THE AREA AND SLIGHT UPPER LEVEL RIDGING WILL RESULT IN
CLEARING SKIES AND VERY WARM CONDITIONS FOR THIS TIME OF YEAR.
READINGS WILL BE IN THE LOW TO MID 80S THIS AFTERNOON...WHICH IS
AS MUCH AS 15 DEGREES ABOVE THE CLIMATOLOGICAL NORMAL FOR THIS
TIME OF YEAR AND NEAR RECORD HIGHS.
BY LATE TONIGHT...MODELS ARE IN REASONABLE AGREEMENT THAT THE
UPPER LEVEL CLOSED LOW OUT WEST WILL EVOLVE INTO AN OPEN WAVE AS
IT MOVES ACROSS THE ROCKIES...AND SURFACE LOW PRESSURE WILL
DEVELOP NEAR THE OKLAHOMA PANHANDLE. THIS SURFACE LOW WILL MOVE
ACROSS THE CENTRAL PLAINS AND INTO THE GREAT LAKES REGION FROM
THURSDAY MORNING AND INTO FRIDAY. AS IT DOES...A STRONG COLD FRONT
WILL SWEEP ACROSS THE MISSISSIPPI VALLEY AND INTERACT WITH A
MODERATELY UNSTABLE AIRMASS. MLCAPE VALUES APPROACHING 2000 J/KG
AND A 50 KT MID LEVEL JET WILL SUPPORT AT LEAST A FEW STRONG TO
SEVERE STORMS. STORM MODE IS STILL A LITTLE UNCLEAR AT THE
MOMENT...BUT IT DOES APPEAR SOME STORMS COULD DEVELOP AHEAD OF THE
LINE AS HEIGHT FALLS OVERSPREAD THE REGION...BEFORE CONGEALING
INTO A QLCS STRUCTURE BY LATE THURSDAY EVENING. DAMAGING WINDS AND
LARGE HAIL LOOK TO BE THE MAIN THREATS...WITH A SECONDARY THREAT
OF FLASH FLOODING. TORNADO THREAT LOOKS VERY MINIMAL...AS THE
FAVORABLE JET STRUCTURE REMAINS WELL TO OUR NORTH. WILL CONTINUE
TO MAKE A MENTION OF SEVERE STORMS IN THE HWO WITH THE BEST
CHANCES REMAINING OVER NORTHEAST ARKANSAS...THE MISSOURI
BOOTHEEL...AND PORTIONS OF NORTHWEST TENNESSEE.
BY FRIDAY AFTERNOON...THE FRONT WILL PUSH TO THE SOUTH AND EAST
AS SURFACE HIGH PRESSURE BUILDS IN. TEMPERATURES WILL BE MILD
DURING THE DAY WITH UPPER 60S AND LOWER 70S EXPECTED.
SATURDAY WILL BE A BEAUTIFUL MILD SPRING DAY WITH LOW HUMIDITY...
TEMPERATURES IN THE LOWER 70...AND ABUNDANT SUNSHINE.
LONG TERM...SUNDAY THROUGH EARLY NEXT WEEK...
A STALLED COLD FRONT TO OUR SOUTH WILL PUSH NORTH AS A WARM FRONT
ON SUNDAY MORNING. AS IT DOES...SHOWERS AND THUNDERSTORMS WILL
OVERSPREAD THE REGION BY THE AFTERNOON HOURS. SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO CONTINUE ON MONDAY BEFORE A COLD
FRONT PUSHES THROUGH THE MID-SOUTH BY TUESDAY. CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO MIDWEEK AS RETURN FLOW
REMAINS DOMINANT ACROSS THE REGION.
AC3
&&
.AVIATION...
12Z TAF CYCLE (08/12Z-09/12Z)
IFR CONDITIONS IN FOG WILL OCCUR AT KTUP UNTIL 13Z...OTHERWISE
MVFR CONDITIONS ARE POSSIBLE AT THE TAF SITES THROUGH 14Z.
MENTIONED VCTS AT KJBR UNTIL 14Z WITH PATCHY LIGHT RAIN AFFECTING
KMEM...KMKL...AND KJBR UNTIL 14Z. VFR CONDITIONS ARE EXPECTED
AFTER 14Z THROUGH THE REMAINDER OF THE PERIOD.
WINDS TODAY AT KMEM...KMKL...AND KJBR INCREASING FROM THE
SW AT 12-18 KTS WITH GUSTS 20-27 KTS. WINDS TODAY AT KTUP BECOMING
SW 12 KTS. WINDS TONIGHT AT KMEM...KMKL AND KJBR S 8-13 KTS
BECOMING AT KJBR AFTER 09/07Z S 15 KTS WITH GUSTS 22 KTS. WINDS
TONIGHT AT KTUP S 6-8 KTS.
JCL
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1000 AM CDT WED APR 8 2015
.UPDATE...HAVE INCREASED POPS 10-20% ACROSS THE WESTERN COUNTIES AND
SEGMENTED THE MORNING TIME PERIOD INTO THREE HOUR BLOCKS TO BETTER
ACCOUNT FOR SHOWER TIMING AND PROGRESSION NORTHEASTWARD. HAVE
LOWERED TEMPERATURES OUT WEST GIVEN ADDITIONAL SHOWER COVERAGE
AND ASSOCIATED CLOUD COVER. THIS TREND MAY NEED TO BE REVISITED IF
HRRR OUTPUT IS AN ACCURATE INDICATION OF SHOWER EVOLUTION TODAY.
UPDATES ARE OUT AND UPDATED DISCUSSION CAN BE FOUND BELOW. /ALLEN/
&&
.DISCUSSION...ISENTROPIC LIFT IN COMBINATION WITH A MID- TO UPPER-
LEVEL DIVERGENCE DUE TO INCREASING WIND SPEEDS ROUNDING THE BASE OF
A CLOSED H5 LOW OVER NEVADA IS AIDING ELEVATED SHOWER AND
THUNDERSTORM DEVELOPMENT ALONG THE RIO GRANDE. THE 12Z KDRT SOUNDING
REVEALED MUCAPE VALUES NEAR 1000-1500 J/KG WITH THE LFC LOCATED NEAR
10 KFT. THIS HEIGHT IS CO-LOCATED WITH MOISTURE LADEN ISENTROPIC
UPGLIDE WITHIN THIS LAYER AND THUS SUPPORTING SOME THUNDERSTORM
ACTIVITY. THE RAP/HRRR ARE THE MORE AGGRESSIVE SHORT TERM MODELS BUT
SO FAR HAVE BEEN MORE CORRECT OVER PAST COUPLE HOURS. HAVE TRENDED
THE NEXT 3-12 HOURS THIS DIRECTION AND BUMPED UP POPS ALONG AND WEST
OF I-35...ESPECIALLY FOR WESTERN REGIONS AND THE SOUTHERN EDWARDS
PLATEAU. A STRONG STORM OR TWO MAY BE POSSIBLE OUT WEST THIS
AFTERNOON AND TRENDS WILL NEED MONITORED CLOSELY IF ANOTHER POSSIBLE
SHORTWAVE EMBEDDED WITHIN THE INCREASING MID LEVEL FLOW SUPPORTS
GREATER COVERAGE LIKE THE HRRR SUGGESTS. SPC SSEO GIVES CONFIDENCE
THAT THE WEST IS THE FAVORED REGION FOR STRONGER ACTIVITY BUT THE
AMOUNT OF OVERALL PRECIPITATION COVERAGE IS STILL A QUESTION. NOT
READY TO FULLY LEAN TOWARDS THE AGGRESSIVE HRRR DIRECTION ON THIS
UPDATE BUT WILL MONITOR FOR FUTURE UPDATES. /ALLEN/
&&
.PREV DISCUSSION... /ISSUED 651 AM CDT WED APR 8 2015/
AVIATION...
MVFR CIGS SHOULD SCATTER OUT FIRST AT KAUS...THEN LATER AT
KSAT/KSSF. WINDS WILL BE S-SE AND FAIRLY STEADY AT 10-15 KTS
THROUGH THE FORECAST PERIOD...BUT DID INCLUDE SOME HIGHER GUSTS
FOR MID TO LATE MORNING. THE ARRIVAL OF A SHORTWAVE TROUGH AND
MORE FAVORABLE SURFACE HEATING SHOULD LEAD TO A BETTER CHANCE OF
-TSRA AT KDRT...SO INCLUDED THAT AS A PROB30 FOR LATE THIS
AFTERNOON AND EARLY EVENING. LOOK FOR MOIST GULF FLOW TO RE-
ESTABLISH MVFR...THEN IFR CIGS OVERNIGHT INTO THURSDAY MORNING.
PREV DISCUSSION... /ISSUED 357 AM CDT WED APR 8 2015/
SHORT TERM (TODAY THROUGH THURSDAY)...
SOUTHERLY LOWER LEVEL FLOW WILL MAINTAIN A MOIST AIRMASS TODAY
INTO THURSDAY WITH A PATTERN OF NIGHT AND MORNING STRATUS MIXING
OUT IN THE AFTERNOON. AN UPPER LEVEL JET STREAK WILL MOVE ACROSS
TEXAS TODAY INTO TONIGHT PUSHING THE DRYLINE EAST ACROSS WESTERN
TEXAS. SOME SHOWERS AND THUNDERSTORMS WILL FORM ALONG THE DRYLINE
AND OVER THE SERRIANAS DEL BURRO AND THEN MOVE ACROSS THE EDWARDS
PLATEAU AND HILL COUNTRY TODAY AND TOWARD THE I-35 CORRIDOR
TONIGHT. CAPE VALUES INDICATE SOME STORMS IN THE EDWARDS PLATEAU
MAY BE STRONG TO MARGINALLY SEVERE THIS AFTERNOON INTO EVENING.
AN UPPER LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN MOVES ACROSS
THE NORTHERN PLAINS FORCING THE DRYLINE EAST INTO THE EDWARDS
PLATEAU AND POSSIBLY FAR NORTHERN HILL COUNTRY ON THURSDAY. THE
MOIST AXIS SHIFTS EAST WITH SHOWERS AND THUNDERSTORMS MAINLY
NORTHEAST OF I-10. CAPE VALUES AGAIN INDICATE A POSSIBILITY OF
STRONG TO MARGINALLY SEVERE STORMS ON THURSDAY. HOWEVER...A
CAPPING INVERSION OF WARM MID LEVEL TEMPERATURES MAY INHIBIT
DEVELOPMENT TODAY AND THURSDAY.
LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...
THE UPPER LEVEL TROUGH CONTINUES FURTHER TO THE NORTHEAST ACROSS
THE GREAT LAKES AND THEN PHASES WITH AN UPPER LEVEL TROUGH OVER
SOUTHEASTERN CANADA. THIS FORCES A COLD FRONT INTO SOUTH CENTRAL
TEXAS ON FRIDAY. SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG THE
FRONT WITH CONVECTIVE PARAMETERS INDICATING A POTENTIAL FOR STRONG
TO MARGINALLY SEVERE STORMS. AGAIN...THIS DEPENDS ON THE AMOUNT OF
INSTABILITY AND THE BREAKING OF THE CAPPING INVERSION. THE FRONT
STALLS JUST SOUTH OF SOUTH CENTRAL TEXAS FRIDAY NIGHT AND THEN
DISSIPATES SATURDAY AS AN UPPER LEVEL TROUGH CURRENTLY OVER JUST
SOUTH OF THE GULF OF ALASKA MOVES INTO NORTHWESTERN MEXICO. THIS
TROUGH MOVES ACROSS TEXAS ON MONDAY WHILE FORCING A PACIFIC FRONT
OR A DRYLINE INTO WESTERN PARTS OF SOUTH CENTRAL TEXAS.
HOWEVER...THERE IS SOME UNCERTAINTY ON ITS SPEED SINCE IT HAS NOT
YET BEEN SAMPLED BY THE NORTH AMERICAN UPPER AIR OBSERVATION
NETWORK. WILL MAINTAIN SHOWERS AND THUNDERSTORMS THIS WEEKEND
ENDING FROM WEST TO EAST ON MONDAY AS THE TROUGH MOVES EAST OF OUR
AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 83 69 85 66 79 / 20 20 30 30 50
AUSTIN BERGSTROM INTL AIRPORT 84 69 83 66 78 / 20 20 30 30 50
NEW BRAUNFELS MUNI AIRPORT 86 68 86 66 81 / 10 20 20 20 50
BURNET MUNI AIRPORT 82 67 85 64 75 / 30 40 30 30 50
DEL RIO INTL AIRPORT 84 68 90 68 83 / 40 40 - 20 60
GEORGETOWN MUNI AIRPORT 83 68 84 65 75 / 20 20 30 40 50
HONDO MUNI AIRPORT 86 68 87 67 81 / 20 30 10 10 50
SAN MARCOS MUNI AIRPORT 82 69 85 66 80 / 10 20 30 20 50
LA GRANGE - FAYETTE REGIONAL 84 70 84 69 81 / - 10 30 20 50
SAN ANTONIO INTL AIRPORT 86 70 86 67 80 / 20 20 20 10 50
STINSON MUNI AIRPORT 87 69 86 68 81 / 10 20 20 10 50
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...01
SYNOPTIC/GRIDS...15
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
930 AM CDT WED APR 8 2015
.UPDATE...HAVE INCREASED POPS 10-20% ACROSS THE WESTERN COUNTIES AND
SEGMENTED THE MORNING TIME PERIOD INTO THREE HOUR BLOCKS TO BETTER
ACCOUNT FOR SHOWER TIMING AND PROGRESSION NORTHEASTWARD. HAVE
LOWERED TEMPERATURES OUT WEST GIVEN ADDITIONAL SHOWER COVERAGE
AND ASSOCIATED CLOUD COVER. THIS TREND MAY NEED TO BE REVISITED IF
HRRR OUTPUT IS AN ACCURATE INDICATION OF SHOWER EVOLUTION TODAY.
UPDATES ARE OUT AND UPDATED DISCUSSION CAN BE FOUND BELOW. /ALLEN/
&&
.DISCUSSION...ISENTROPIC LIFT IN COMBINATION WITH A MID- TO UPPER-
LEVEL DIVERGENCE DUE TO INCREASING WIND SPEEDS ROUNDING THE BASE OF
A CLOSED H5 LOW OVER NEVADA IS AIDING ELEVATED SHOWER AND
THUNDERSTORM DEVELOPMENT ALONG THE RIO GRANDE. THE 12Z KDRT SOUNDING
REVEALED MUCAPE VALUES NEAR 1500 J/KG WITH THE LFC LOCATED NEAR 10
KFT. THIS HEIGHT IS CO-LOCATED WITH MOISTURE LADEN ISENTROPIC
UPGLIDE WITHIN THIS LAYER AND THUS SUPPORTING SOME THUNDERSTORM
ACTIVITY. THE RAP/HRRR ARE THE MORE AGGRESSIVE SHORT TERM MODELS
BUT SO FAR HAVE BEEN MORE CORRECT OVER PAST COUPLE HOURS. HAVE
TRENDED THE NEXT 3-12 HOURS THIS DIRECTION AND BUMPED UP POPS
ALONG AND WEST OF I-35...ESPECIALLY FOR WESTERN REGIONS AND THE
SOUTHERN EDWARDS PLATEAU. A STRONG STORM OR TWO MAY BE POSSIBLE
OUT WEST THIS AFTERNOON AND TRENDS WILL NEED MONITORED CLOSELY IF
ANOTHER POSSIBLE SHORTWAVE EMBEDDED WITHIN THE INCREASING MID
LEVEL FLOW SUPPORTS GREATER COVERAGE LIKE THE HRRR SUGGESTS. SPC
SSEO GIVES CONFIDENCE THAT THE WEST IS THE FAVORED REGION FOR
STRONGER ACTIVITY BUT THE AMOUNT OF OVERALL PRECIPITATION COVERAGE
IS STILL A QUESTION. NOT READY TO FULLY LEAN TOWARDS THE
AGGRESSIVE HRRR DIRECTION ON THIS UPDATE BUT WILL MONITOR FOR
FUTURE UPDATES. /ALLEN/
&&
.PREV DISCUSSION... /ISSUED 651 AM CDT WED APR 8 2015/
AVIATION...
MVFR CIGS SHOULD SCATTER OUT FIRST AT KAUS...THEN LATER AT
KSAT/KSSF. WINDS WILL BE S-SE AND FAIRLY STEADY AT 10-15 KTS
THROUGH THE FORECAST PERIOD...BUT DID INCLUDE SOME HIGHER GUSTS
FOR MID TO LATE MORNING. THE ARRIVAL OF A SHORTWAVE TROUGH AND
MORE FAVORABLE SURFACE HEATING SHOULD LEAD TO A BETTER CHANCE OF
-TSRA AT KDRT...SO INCLUDED THAT AS A PROB30 FOR LATE THIS
AFTERNOON AND EARLY EVENING. LOOK FOR MOIST GULF FLOW TO RE-
ESTABLISH MVFR...THEN IFR CIGS OVERNIGHT INTO THURSDAY MORNING.
PREV DISCUSSION... /ISSUED 357 AM CDT WED APR 8 2015/
SHORT TERM (TODAY THROUGH THURSDAY)...
SOUTHERLY LOWER LEVEL FLOW WILL MAINTAIN A MOIST AIRMASS TODAY
INTO THURSDAY WITH A PATTERN OF NIGHT AND MORNING STRATUS MIXING
OUT IN THE AFTERNOON. AN UPPER LEVEL JET STREAK WILL MOVE ACROSS
TEXAS TODAY INTO TONIGHT PUSHING THE DRYLINE EAST ACROSS WESTERN
TEXAS. SOME SHOWERS AND THUNDERSTORMS WILL FORM ALONG THE DRYLINE
AND OVER THE SERRIANAS DEL BURRO AND THEN MOVE ACROSS THE EDWARDS
PLATEAU AND HILL COUNTRY TODAY AND TOWARD THE I-35 CORRIDOR
TONIGHT. CAPE VALUES INDICATE SOME STORMS IN THE EDWARDS PLATEAU
MAY BE STRONG TO MARGINALLY SEVERE THIS AFTERNOON INTO EVENING.
AN UPPER LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN MOVES ACROSS
THE NORTHERN PLAINS FORCING THE DRYLINE EAST INTO THE EDWARDS
PLATEAU AND POSSIBLY FAR NORTHERN HILL COUNTRY ON THURSDAY. THE
MOIST AXIS SHIFTS EAST WITH SHOWERS AND THUNDERSTORMS MAINLY
NORTHEAST OF I-10. CAPE VALUES AGAIN INDICATE A POSSIBILITY OF
STRONG TO MARGINALLY SEVERE STORMS ON THURSDAY. HOWEVER...A
CAPPING INVERSION OF WARM MID LEVEL TEMPERATURES MAY INHIBIT
DEVELOPMENT TODAY AND THURSDAY.
LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...
THE UPPER LEVEL TROUGH CONTINUES FURTHER TO THE NORTHEAST ACROSS
THE GREAT LAKES AND THEN PHASES WITH AN UPPER LEVEL TROUGH OVER
SOUTHEASTERN CANADA. THIS FORCES A COLD FRONT INTO SOUTH CENTRAL
TEXAS ON FRIDAY. SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG THE
FRONT WITH CONVECTIVE PARAMETERS INDICATING A POTENTIAL FOR STRONG
TO MARGINALLY SEVERE STORMS. AGAIN...THIS DEPENDS ON THE AMOUNT OF
INSTABILITY AND THE BREAKING OF THE CAPPING INVERSION. THE FRONT
STALLS JUST SOUTH OF SOUTH CENTRAL TEXAS FRIDAY NIGHT AND THEN
DISSIPATES SATURDAY AS AN UPPER LEVEL TROUGH CURRENTLY OVER JUST
SOUTH OF THE GULF OF ALASKA MOVES INTO NORTHWESTERN MEXICO. THIS
TROUGH MOVES ACROSS TEXAS ON MONDAY WHILE FORCING A PACIFIC FRONT
OR A DRYLINE INTO WESTERN PARTS OF SOUTH CENTRAL TEXAS.
HOWEVER...THERE IS SOME UNCERTAINTY ON ITS SPEED SINCE IT HAS NOT
YET BEEN SAMPLED BY THE NORTH AMERICAN UPPER AIR OBSERVATION
NETWORK. WILL MAINTAIN SHOWERS AND THUNDERSTORMS THIS WEEKEND
ENDING FROM WEST TO EAST ON MONDAY AS THE TROUGH MOVES EAST OF OUR
AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 83 69 85 66 79 / 20 20 30 30 50
AUSTIN BERGSTROM INTL AIRPORT 84 69 83 66 78 / 20 20 30 30 50
NEW BRAUNFELS MUNI AIRPORT 86 68 86 66 81 / 10 20 20 20 50
BURNET MUNI AIRPORT 82 67 85 64 75 / 30 40 30 30 50
DEL RIO INTL AIRPORT 84 68 90 68 83 / 40 40 - 20 60
GEORGETOWN MUNI AIRPORT 83 68 84 65 75 / 20 20 30 40 50
HONDO MUNI AIRPORT 86 68 87 67 81 / 20 30 10 10 50
SAN MARCOS MUNI AIRPORT 82 69 85 66 80 / 10 20 30 20 50
LA GRANGE - FAYETTE REGIONAL 84 70 84 69 81 / - 10 30 20 50
SAN ANTONIO INTL AIRPORT 86 70 86 67 80 / 20 20 20 10 50
STINSON MUNI AIRPORT 87 69 86 68 81 / 10 20 20 10 50
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...01
SYNOPTIC/GRIDS...15
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION...CORRECTED
NWS SAN ANGELO TX
807 AM CDT WED APR 8 2015
.AVIATION...
/12Z TAFS/
Good flight conditions will prevail at KABI, KSJT, and KBBD through
the next 24 hours. Farther south, ceilings near 1500 feet this
morning will lift to around 4000 feet by late morning. Southwest
wind gusts near 25 kts are likely late this morning and afternoon at
all terminals. These wind gusts will diminish to near 20 kts after
sunset. Showers and thunderstorms may develop this afternoon/evening.
However, confidence in timing/location remain high enough not to
include in the TAFs at this time.
&&
.PREV DISCUSSION... /ISSUED 458 AM CDT Wed Apr 8 2015/
SHORT TERM...
(Today and Tonight)
..Severe weather possible this afternoon/evening...
The forecast challenges are plentiful through the next 24 hours. The
TTU WRF and HRRR models indicate showers should be developing to our
southwest at 4 AM, moving into the region from west to east this
morning through mid-afternoon. They then try to re-develop
convection to our west by late afternoon, with this convection
dissipating before midnight as it approaches our western counties.
Conversely, the NAM/GFS/ECMWF all show nothing for this morning
through mid afternoon, and then develop convection from mid-
afternoon through midnight at varying locations/intensities across
the region. Given the current satellite imagery and upstream
observations, we`ll lean more towards this scenario.
The NAM/GFS have also trended significantly farther west with the
dryline position this afternoon. The ECMWF brings it farther east
with it positioned along a line from eastern Haskell County, to San
Angelo, to west of Ozona. We`ll take a middle-ground approach with
the expectation of the dryline halting its eastward progression,
being located along the western edge of the forecast area. A
strong cap will remain in place for much of the day. By late
afternoon/early evening, a mid-level jet streak will approach the
area from the southwest. Increasing ascent from this, afternoon
mixing, and convergence along the dryline, may be sufficient to
weaken the cap enough for a few storms to develop.
If this occurs, the environment will be characterized by 1500-2500
J/kg of SBCAPE (possibly more if skies are less cloudy than
currently forecast), steep mid-level lapse rates near 8 C/km, with
0-6km effective shear values of 40-55 kts. With this type of setup,
storms would rapidly become severe/supercells with large hail and
damaging winds the main concerns. Soundings also show low-level
winds backing to the southeast, which really increases 0-3km
helicity values making isolated tornadoes a possibility as well,
especially across the northwestern this of the area which is closer
to the track of the mid-level disturbance.
LONG TERM...
(Thursday through Tuesday)
Rain chances remain in most periods of the long term. Another cold
front will push across West Central Texas on Thursday and bring
cooler air, and it will enhance the rain potential for Friday
through the weekend. A developing upper-level disturbance well to
our west will also enhance the rain potential by creating
southwest flow aloft, where embedded minor disturbance will move
across Texas. Isentropic upglide will be best across our southern
counties from Friday through the weekend. Thus, the best chance
for rain will be there. The ECMWF is more aggressive than the GFS
regarding QPF amounts for Friday through the weekend, and the
ECMWF indicates better divergence aloft over Texas for those
periods. So, continuing the best rain chances across our southern
counties looks best. Plus, continuing a PoP forecast closer to
the ECMWF looks better than something closer to the drier GFS.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 84 65 86 55 73 / 30 40 5 10 20
San Angelo 84 65 86 57 74 / 40 40 10 10 40
Junction 83 64 87 61 75 / 30 30 30 10 50
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Aviation: Doll
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
6423 AM CDT WED APR 8 2015
.AVIATION...
/12Z TAFS/
Good flight conditions will prevail at KABI, KSJT, and KBBD through
the next 24 hours. Farther south, ceilings near 1500 feet this
morning will lift to around 4000 feet by late morning. Southwest
wind gusts near 25 kts are likely late this morning and afternoon at
all terminals. These wind gusts will diminish to near 20 kts after
sunset. Showers and thunderstorms may develop this afternoon/evening.
However, confidence in timing/location remain high enough not to
include in the TAFs at this time.
&&
.PREV DISCUSSION... /ISSUED 458 AM CDT Wed Apr 8 2015/
SHORT TERM...
(Today and Tonight)
..Severe weather possible this afternoon/evening...
The forecast challenges are plentiful through the next 24 hours. The
TTU WRF and HRRR models indicate showers should be developing to our
southwest at 4 AM, moving into the region from west to east this
morning through mid-afternoon. They then try to re-develop
convection to our west by late afternoon, with this convection
dissipating before midnight as it approaches our western counties.
Conversely, the NAM/GFS/ECMWF all show nothing for this morning
through mid afternoon, and then develop convection from mid-
afternoon through midnight at varying locations/intensities across
the region. Given the current satellite imagery and upstream
observations, we`ll lean more towards this scenario.
The NAM/GFS have also trended significantly farther west with the
dryline position this afternoon. The ECMWF brings it farther east
with it positioned along a line from eastern Haskell County, to San
Angelo, to west of Ozona. We`ll take a middle-ground approach with
the expectation of the dryline halting its eastward progression,
being located along the western edge of the forecast area. A
strong cap will remain in place for much of the day. By late
afternoon/early evening, a mid-level jet streak will approach the
area from the southwest. Increasing ascent from this, afternoon
mixing, and convergence along the dryline, may be sufficient to
weaken the cap enough for a few storms to develop.
If this occurs, the environment will be characterized by 1500-2500
J/kg of SBCAPE (possibly more if skies are less cloudy than
currently forecast), steep mid-level lapse rates near 8 C/km, with
0-6km effective shear values of 40-55 kts. With this type of setup,
storms would rapidly become severe/supercells with large hail and
damaging winds the main concerns. Soundings also show low-level
winds backing to the southeast, which really increases 0-3km
helicity values making isolated tornadoes a possibility as well,
especially across the northwestern this of the area which is closer
to the track of the mid-level disturbance.
LONG TERM...
(Thursday through Tuesday)
Rain chances remain in most periods of the long term. Another cold
front will push across West Central Texas on Thursday and bring
cooler air, and it will enhance the rain potential for Friday
through the weekend. A developing upper-level disturbance well to
our west will also enhance the rain potential by creating
southwest flow aloft, where embedded minor disturbance will move
across Texas. Isentropic upglide will be best across our southern
counties from Friday through the weekend. Thus, the best chance
for rain will be there. The ECMWF is more aggressive than the GFS
regarding QPF amounts for Friday through the weekend, and the
ECMWF indicates better divergence aloft over Texas for those
periods. So, continuing the best rain chances across our southern
counties looks best. Plus, continuing a PoP forecast closer to
the ECMWF looks better than something closer to the drier GFS.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 84 65 86 55 73 / 30 40 5 10 20
San Angelo 84 65 86 57 74 / 40 40 10 10 40
Junction 83 64 87 61 75 / 30 30 30 10 50
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Aviation: Doll
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
436 AM MDT WED APR 8 2015
.SHORT TERM...(TODAY THROUGH FRIDAY NIGHT)
ISSUED AT 206 AM MDT WED APR 8 2015
TODAY...FIRST CHALLENGE IS THE FOG. AREAS OF FOG HAVE DEVELOPED FROM
THE EASTERN SLOPES OF THE LARAMIE RANGE TO CHEYENNE...KIMBALL AND
SIDNEY. BASED ON SATELLITE LOOPS AND THE BOUNDARY LAYER MODEL
PROGS...EXPECT FOG TO CONTINUE THROUGH MID MORNING BEFORE
DISSIPATING. WITH AREAS OF DENSE FOG INCREASING IN COVERAGE FROM
CHEYENNE WESTWARD TO THE FOOTHILLS...AS SEEN ON WEBCAMS...WE HAVE
OPTED TO ISSUE A DENSE FOG ADVISORY FOR CHEYENNE AND THE EASTERN
FOOTHILLS OF THE LARAMIE RANGE THROUGH MID MORNING.
IN THE AFTERNOON...PROGRESSIVE SHORTWAVE TROUGH ALOFT MOVES TO
CENTRAL WYOMING AND AN INVERTED SURFACE TROUGH EXTENDING FROM LUSK
TO PINE BLUFFS. IMPRESSIVE 850 MB THETA-E RIDGE AXIS WILL ALSO BE
ALONG THE WYOMING AND NEBRASKA STATE LINE BY LATE AFTERNOON.
ALTHOUGH CAPE IS RELATIVELY MINIMAL...ENOUGH DYNAMIC LIFT AND
QUASIGEOSTROPHIC LIFT WILL COMBINE WITH SHEAR AND INSTABILITY TO
PRODUCE A FEW STRONG TO SEVERE THUNDERSTORMS LATE THIS AFTERNOON AND
THIS EVENING ROUGHLY EAST OF A LUSK TO PINE BLUFFS LINE.
TONIGHT...THE SHORTWAVE TROUGH ALOFT AND ITS ASSOCIATED COLD FRONT
MOVE EASTWARD OVER OUR REGION. WITH DECENT DYNAMICS AND PLENTY OF
LOW AND MID LEVEL MOISTURE...WILL SEE WIDESPREAD
SHOWERS...ESPECIALLY OVER THE NORTHERN LOCATIONS FROM DOUGLAS TO
CHADRON.
THURSDAY...AS THE SHORTWAVE TROUGH ALOFT MOVES FURTHER AWAY TO OUR
EAST...EXPECT AREAL COVERAGE OF SHOWERS TO DECREASE AS WELL. COOL
AND WINDY DAY IN THE WAKE OF THE COLD FRONT
FRIDAY AND FRIDAY NIGHT...SURFACE TROUGH EXTENDS FROM NEAR LUSK TO
PINE BLUFFS IN THE AFTERNOON. MODELS PAINTING SOME QPF...THOUGH WILL
BLEND AND GO ALONG WITH OUR NEIGHBORS KEEPING OUR WEATHER DRY.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 300 AM MDT WED APR 8 2015
DEPARTING SHORTWAVE FOR SATURDAY WITH BREEZY WINDS AND DRY
CONDITIONS EXPECTED. SHOULD BE FAIRLY NICE TEMPERATURE WISE AS
700MB TEMPERATURES REMAIN ABOVE FREEZING. LOOKING AT LOW 70S IN
THE PANHANDLE AND LOW 60S WEST OF THE LARAMIE RANGE.
CURRENT MODEL RUNS HAVE BACKED OFF ON WINDS FOR SUNDAY/MONDAY
TIME FRAME. GFS NOW SHOWING THE STRONGER WINDS BEGINNING TUESDAY
NIGHT INTO WEDNESDAY.
NEED TO BE WATCHING A SLOW MOVING LOW PRESSURE SYSTEM THE FIRST
PART OF NEXT WEEK. GFS AND ECMWF TRACK THIS LOW ACROSS SOUTHERN
COLORADO MONDAY WITH WRAP AROUND MOISTURE MAKING IT INTO OUR
EASTERN AND CENTRAL ZONES MONDAY AFTERNOON/NIGHT. RIGHT
NOW...FORECAST 700MB TEMPERATURES ARE STILL ABOVE FREEZING...SO
MUCH OF THIS MOISTURE SHOULD FALL AS LIQUID. BUT IF THEY SHOULD
COME IN JUST A FEW DEGREES COLDER OR THE LOW TRACKS A LITTLE
FURTHER NORTH...WE COULD BE LOOKING AT SIGNIFICANT SNOW FALL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1102 PM MDT TUE APR 7 2015
IFR/LIFR CONDITIONS EXPECTED ONCE AGAIN OVERNIGHT WITH EAST TO
SOUTHEAST UPSLOPE FLOW. HRRR GUIDANCE KEEPS LOW CONDITIONS IN
THROUGH MOST OF THE MORNING FOR AREAS EAST OF THE LARAMIE RANGE
BEFORE BREAKING AT 17Z OR SO.
&&
.FIRE WEATHER...
ISSUED AT 206 AM MDT WED APR 8 2015
MINIMAL CONCERNS AS HUMIDITIES WILL BE ABOVE
CRITICAL THRESHOLDS TODAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RUBIN
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...RUBIN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
421 AM MDT WED APR 8 2015
.SHORT TERM...(TODAY THROUGH FRIDAY NIGHT)
ISSUED AT 206 AM MDT WED APR 8 2015
TODAY...FIRST CHALLENGE IS THE FOG. AREAS OF FOG HAVE DEVELOPED FROM
THE EASTERN SLOPES OF THE LARAMIE RANGE TO CHEYENNE...KIMBALL AND
SIDNEY. BASED ON SATELLITE LOOPS AND THE BOUNDARY LAYER MODEL
PROGS...EXPECT FOG TO CONTINUE THROUGH MID MORNING BEFORE
DISSIPATING. WITH AREAS OF DENSE FOG INCREASING IN COVERAGE FROM
CHEYENNE WESTWARD TO THE FOOTHILLS...AS SEEN ON WEBCAMS...WE HAVE
OPTED TO ISSUE A DENSE FOG ADVISORY FOR CHEYENNE AND THE EASTERN
FOOTHILLS OF THE LARAMIE RANGE THROUGH MID MORNING.
IN THE AFTERNOON...PROGRESSIVE SHORTWAVE TROUGH ALOFT MOVES TO
CENTRAL WYOMING AND AN INVERTED SURFACE TROUGH EXTENDING FROM LUSK
TO PINE BLUFFS. IMPRESSIVE 850 MB THETA-E RIDGE AXIS WILL ALSO BE
ALONG THE WYOMING AND NEBRASKA STATE LINE BY LATE AFTERNOON.
ALTHOUGH CAPE IS RELATIVELY MINIMAL...ENOUGH DYNAMIC LIFT AND
QUASIGEOSTROPHIC LIFT WILL COMBINE WITH SHEAR AND INSTABILITY TO
PRODUCE A FEW STRONG TO SEVERE THUNDERSTORMS LATE THIS AFTERNOON AND
THIS EVENING ROUGHLY EAST OF A LUSK TO PINE BLUFFS LINE.
TONIGHT...THE SHORTWAVE TROUGH ALOFT AND ITS ASSOCIATED COLD FRONT
MOVE EASTWARD OVER OUR REGION. WITH DECENT DYNAMICS AND PLENTY OF
LOW AND MID LEVEL MOISTURE...WILL SEE WIDESPREAD
SHOWERS...ESPECIALLY OVER THE NORTHERN LOCATIONS FROM DOUGLAS TO
CHADRON.
THURSDAY...AS THE SHORTWAVE TROUGH ALOFT MOVES FURTHER AWAY TO OUR
EAST...EXPECT AREAL COVERAGE OF SHOWERS TO DECREASE AS WELL. COOL
AND WINDY DAY IN THE WAKE OF THE COLD FRONT
FRIDAY AND FRIDAY NIGHT...SURFACE TROUGH EXTENDS FROM NEAR LUSK TO
PINE BLUFFS IN THE AFTERNOON. MODELS PAINTING SOME QPF...THOUGH WILL
BLEND AND GO ALONG WITH OUR NEIGHBORS KEEPING OUR WEATHER DRY.
.FIRE WEATHER...MINIMAL CONCERNS AS HUMIDITIES WILL BE ABOVE
CRITICAL THRESHOLDS TODAY.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 300 AM MDT WED APR 8 2015
DEPARTING SHORTWAVE FOR SATURDAY WITH BREEZY WINDS AND DRY
CONDITIONS EXPECTED. SHOULD BE FAIRLY NICE TEMPERATURE WISE AS
700MB TEMPERATURES REMAIN ABOVE FREEZING. LOOKING AT LOW 70S IN
THE PANHANDLE AND LOW 60S WEST OF THE LARAMIE RANGE.
CURRENT MODEL RUNS HAVE BACKED OFF ON WINDS FOR SUNDAY/MONDAY
TIME FRAME. GFS NOW SHOWING THE STRONGER WINDS BEGINNING TUESDAY
NIGHT INTO WEDNESDAY.
NEED TO BE WATCHING A SLOW MOVING LOW PRESSURE SYSTEM THE FIRST
PART OF NEXT WEEK. GFS AND ECMWF TRACK THIS LOW ACROSS SOUTHERN
COLORADO MONDAY WITH WRAP AROUND MOISTURE MAKING IT INTO OUR
EASTERN AND CENTRAL ZONES MONDAY AFTERNOON/NIGHT. RIGHT
NOW...FORECAST 700MB TEMPERATURES ARE STILL ABOVE FREEZING...SO
MUCH OF THIS MOISTURE SHOULD FALL AS LIQUID. BUT IF THEY SHOULD
COME IN JUST A FEW DEGREES COLDER OR THE LOW TRACKS A LITTLE
FURTHER NORTH...WE COULD BE LOOKING AT SIGNIFICANT SNOW FALL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1102 PM MDT TUE APR 7 2015
IFR/LIFR CONDITIONS EXPECTED ONCE AGAIN OVERNIGHT WITH EAST TO
SOUTHEAST UPSLOPE FLOW. HRRR GUIDANCE KEEPS LOW CONDITIONS IN
THROUGH MOST OF THE MORNING FOR AREAS EAST OF THE LARAMIE RANGE
BEFORE BREAKING AT 17Z OR SO.
&&
.FIRE WEATHER...
ISSUED AT 206 AM MDT WED APR 8 2015
MINIMAL CONCERNS AS HUMIDITIES WILL BE ABOVE
CRITICAL THRESHOLDS TODAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RUBIN
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...RUBIN
AREA FORECAST DISCUSSION
NWS NEW YORK NY
140 PM EDT WED APR 8 2015
.SYNOPSIS...
A NEARLY STATIONARY FRONT WILL REMAIN TO THE SOUTH THROUGH
THURSDAY. LOW PRESSURE MOVES THROUGH THE GREAT LAKES WITH A WARM
FRONT APPROACHING THURSDAY NIGHT. THE WARM FRONT PUSHES NORTHWEST
OF THE REGION EARLY FRIDAY WITH LOW PRESSURE DEEPENING IN
SOUTHEAST CANADA. AN ASSOCIATED COLD FRONT WILL MOVE ACROSS FRIDAY
EVENING. A SECONDARY WEAK COLD FRONT MOVES ACROSS SATURDAY WITH
HIGH PRESSURE FROM THE WEST BUILDING INTO THE REGION FOR THE REST
OF THE WEEKEND. HIGH PRESSURE MOVES OFFSHORE EARLY NEXT WEEK
AFTER WHICH LOW PRESSURE APPROACHES FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOR THIS UPDATE HAVE CUT BACK SIGNIFICANTLY ON CHANCES OF RAIN OR
DRIZZLE. COOL/DRY AIR DAMMING WEST EXTENDING SW FROM STRONG HIGH
PRESSURE BUILDING ACROSS NEW ENGLAND...WITH THE OKX 12Z SOUNDING
VERY DRY BELOW 900 MB...AND LOW LEVELS FCST TO REMAIN SO THROUGH
MUCH OF TODAY AS THE DAMMING REMAINS IN PLACE. THIS DAMMING SHOULD
SHUNT MOST OF THE PRECIP ASSOCIATED WITH A DEVELOPING WEAK LOW E
OF THE VA CAPE...AND WEAKEN SHOWERS MOVING E FROM THE SUSQUEHANNA
VALLEY IN PA. HRRR STILL DOES FCST SOME OF THIS ACTIVITY TO MAKE
IT INTO AREAS WEST OF NYC THIS AFTERNOON...WITH MORE ISOLD
ACTIVITY FARTHER EAST VIA MOISTURE AND WEAK H7-8 LIFT...SO STILL
HAVE SLIGHT CHANCE POP THIS AFTERNOON FOR SRN CT AND LONG ISLAND.
HIGH TEMPS TODAY WILL LIKELY RUN 10-15 DEGREES BELOW SEASONABLE
TODAY...LOWER/MID 40S. COMBINED WITH NE WINDS OF 15 TO 20 MPH AND
GUSTS TO 30 MPH ALONG THE COAST BETWEEN THE HIGH TO THE NORTH AND
DEVELOPING LOW TO OUR SOUTH...IT WILL BE A RAW DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
MODELS IN GOOD AGREEMENT WITH A DEVELOPING CENTRAL US TROUGH AS A
NORTHERN STREAM SHORTWAVE AND UPPER LOW EJECTING OUT OF THE
ROCKIES PHASE...RESULTING IN AN UPSTREAM GRADUAL RISE IN HEIGHTS
UP THE EASTERN SEABOARD.
RESULTANT LOW PRESSURE TRACKS FROM THE CENTRAL PLAINS TO THE CENTRAL
GREAT LAKES...WITH THE COLD FRONT TO THE SOUTH TONIGHT GRADUALLY
WORKING NORTH TOWARDS THE AREA AS A WARM FRONT LATE THU/THU NIGHT.
MEANWHILE...HIGH PRESSURE WILL ONLY SLOWLY RELENT ITS POSITION ACROSS
THE CANADIAN MARITIMES AND DRIFT OFFSHORE.
THE RESULT WILL BE A CONTINUATION OF STRATUS...PERIODS OF RAIN
SHOWERS...AND AREAS OF DRIZZLE TONIGHT INTO THURSDAY WITH A BRISK
AND CHILLY NE FLOW. WITH NORTHERN STREAM SHORTWAVE PASSING TO THE
EAST BY THURSDAY MORNING...SHOWER ACTIVITY MAY BECOME LESS
WIDESPREAD. THEN INCREASING CHANCE FOR SHOWER ACTIVITY LATE
THURSDAY AND MORE SO THURSDAY NIGHT WITH STRONG WARM AIR
ADVECTION PATTERN DEVELOPING OVER APPROACHING WARM FRONT. MOST
WIDESPREAD DRIZZLE WILL LIKELY BE ACROSS AREAS NW AND W OF NYC
WITH SOME OROGRAPHIC LIFT. HAVE ASSIGNED POPS BASED ON ABOVE
THINKING.
ALTHOUGH THERMAL PROFILES SUPPORT LIQUID PRECIPITATION FOR THE
MOST PART...MODELS ARE INDICATING A DEVELOPING LOW-LEVEL COLD
LAYER BETWEEN 975-900 MB AFTER MIDNIGHT INTO EARLY THURSDAY
MORNING...WHICH COULD RESULT IN FREEZING RAIN ACROSS ELEVATIONS
ABOVE 500-750 FT. IF STRENGTH OF COLD LAYER IS CLOSER TO NAM
SOUNDINGS...POTENTIAL FOR A BIT OF SLEET ACROSS INTERIOR TONIGHT.
WILL HOLD OFF ON ANY ADVISORIES FOR THE FREEZING RAIN AT THIS
POINT WITH LIMITED COVERAGE...POTENTIAL FOR SLEET...AND MARGINALLY
COLD CONDITIONS.
HIGH TEMPS THURSDAY WILL LIKELY RUN 10-15 DEGREES BELOW SEASONABLE
ONCE AGAIN (LOWER TO MID 40S)...WITH A CONTINUATION OF THE RAW
CONDITIONS WITH GUSTY NE WINDS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
OVERALL IN THE UPPER LEVELS...THE JET STREAM WILL BE
NORTH OF THE REGION...MOVING INTO THE REGION FRIDAY NIGHT AND JUST
SOUTH OF THE REGION FOR THE WEEKEND BEFORE RISING BACK NORTH EARLY
NEXT WEEK.
IN THE MID LEVELS...THE LONGWAVE RIDGE MOVES OFF THE EAST
COAST THURSDAY NIGHT THROUGH FRIDAY. THERE IS AN EMBEDDED SUBTLE
SHORTWAVE WITH A STREAK OF POSITIVE VORTICITY ADVECTION FRIDAY
WHICH WILL HELP ENHANCE LIFT FOR SHOWERS AND POSSIBLE
THUNDERSTORMS NEAR AREAS WHICH HAVE GREATER MAX TEMPS. A LARGER
SHORTWAVE APPROACHES SATURDAY AND MOVES THROUGH LATE IN THE DAY
WITH A LONGWAVE RIDGE SETTLING IN THEREAFTER.
AT THE SURFACE...THE APPROACH OF A WARM FRONT ASSOCIATED WITH A
PARENT LOW MOVING THROUGH THE GREAT LAKES FRIDAY NIGHT WILL KEEP A
MILD AIR MASS IN PLACE. WARM AND MOIST AIR ADVECTION INCREASE
GOING INTO FRIDAY ONCE THE WARM FRONT IS NORTH OF THE REGION.
A PRETTY STEEP INVERSION WILL BE SET UP AROUND 925MB WHERE TEMPS
COULD REACH AS HIGH AS 19 DEGREES CELSIUS. SOME UNCERTAINTY ON
GROUND TEMPS AND HOW MUCH OF THE HIGHER TEMPS ABOVE MIX DOWN. THE
SOUTHERLY FLOW THROUGHOUT THE ATMOSPHERE AND APPROACH OF A WARM
FRONT SUGGEST AN ADVECTION FOG SETUP. INDICATED PATCHY FOG
DEVELOPING THURSDAY NIGHT INTO FRIDAY AND THEN AREAS OF FOG FRIDAY
ON THE WATERS WHICH WILL PROBABLY TAKE SOME TIME TO DISSIPATE
THROUGH THE DAY. IT IS TOO EARLY TO INDICATE EXPLICITLY IN
FORECAST...BUT THERE IS THE POSSIBILITY OF DENSE FOG.
IN TERMS OF PRECIPITATION...MODELS HAVE SOME DISAGREEMENT WITH
SHOWER DEVELOPMENT ALONG WARM FRONT BUT ENOUGH OF SIGNAL SUGGESTS
SHOWERS OR DRIZZLE WILL BE LIKELY THURSDAY NIGHT INTO FRIDAY. THEN
A LULL IN ACTIVITY WITH THE AREA BEING IN THE WARM SECTOR WITH A
CHANCE OF SHOWERS...BEFORE LIKELY SHOWERS AND POSSIBLE
THUNDERSTORMS MOVE ACROSS FRIDAY AFTERNOON INTO THE EVENING AHEAD
OF A COLD FRONT.
THE COLD FRONT MOVES ACROSS FRIDAY EVENING WITH HIGH PRESSURE TO THE
WEST STARTING TO MOVE EAST. HOWEVER...IT WILL NOT BE THAT PROMINENT
INITIALLY AS THE SHORTWAVE TROUGH AND A SECONDARY WEAK COLD FRONT
MOVE ACROSS SATURDAY. MAINLY DRY CONDITIONS SATURDAY ARE ANTICIPATED
BUT CANNOT RULE OUT A SHOWER ASSOCIATED WITH THE PASSAGE OF FRONT
AND SHORTWAVE...PROBABLY ACROSS THE LOWER HUDSON VALLEY WHERE BETTER
DYNAMICS ARE CONVEYED.
DRY WEATHER FOR SUNDAY AND MONDAY WITH HIGH PRESSURE TAKING OVER.
OVERALL...TEMPS LOOK TO BE A FEW DEGREES ABOVE NORMAL.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE REMAINS NORTHEAST OF THE REGION THROUGH TONIGHT.
MEANWHILE...A STATIONARY FRONT REMAINS TO OUR SOUTH...WITH WAVES
OF LOW PRESSURE RIDING ALONG IT.
GENERALLY VFR THIS AFTERNOON. CIGS THEN FALL TO MVFR THIS
EVENING...AND POSSIBLY IFR OVERNIGHT. CIGS THIS AFTERNOON WILL
START OFF AROUND 3500-4500FT...FALLING TO AROUND 1000 FT AFTER
MIDNIGHT.
WINDS WILL GENERALLY REMAIN FROM THE EAST TO NORTHEAST 10 TO 15 KT
WITH GUSTS INTO THE 20 KT RANGE. WIND GUSTS ARE EXPECTED TO
DIMINISH AFTER 00Z AND SPEEDS WILL FALL TO 10 KT OR LESS.
CIGS DO NOT IMPROVE MUCH DURING THE DAY THURSDAY.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT:
HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILING HEIGHTS. TIMING OF WIND SPEEDS AND GUSTS MAY BE OFF BY
+/- 1-2 HOURS.
KLGA FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILING HEIGHTS. TIMING OF WIND SPEEDS AND GUSTS MAY BE OFF BY
+/- 1-2 HOURS.
KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILING HEIGHTS. TIMING OF WIND SPEEDS AND GUSTS MAY BE OFF BY
+/- 1-2 HOURS.
KTEB FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILING HEIGHTS. TIMING OF WIND SPEEDS AND GUSTS MAY BE OFF BY
+/- 1-2 HOURS.
KHPN FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILING HEIGHTS. TIMING OF WIND SPEEDS AND GUSTS MAY BE OFF BY
+/- 1-2 HOURS.
KISP FCSTER COMMENTS: AMENDMENTS POSSIBLE DUE TO CHANGES IN
CEILING HEIGHTS. TIMING OF WIND SPEEDS AND GUSTS MAY BE OFF BY
+/- 1-2 HOURS.
.OUTLOOK FOR 18Z THURSDAY THROUGH SUNDAY...
.THURSDAY-FRIDAY MORNING...MVFR DURING THE DAY...THEN IFR AT
NIGHT IN PERIODS OF -RA/DZ. LLWS POSSIBLE S/E TERMINALS LATE
THURSDAY NIGHT/FRIDAY MORNING.
.FRIDAY AFTERNOON/NIGHT...MVFR OR LOWER IN SHRA AND SLIGHT CHANCE
TSTMS INTO FRIDAY EVENING...THEN BECOMING VFR. NW WINDS G20-25KT
POSSIBLE FROM MID FRIDAY EVENING ON.
.SATURDAY...VFR. NW WINDS G15-20KT POSSIBLE DURING THE DAYLIGHT
HOURS.
.SUN-MON...VFR.
&&
.MARINE...
A TIGHTENING PRESSURE GRADIENT AS HIGH PRESSURE BUILDS INTO NEW
ENGLAND AND A WEAK LOW DEVELOPS ALONG THE MID ATLANTIC COAST
EXPECTED TO DEVELOP MARGINAL GALE CONDITIONS ON THE OCEAN WATERS
AND SCA CONDITIONS OVER THE REMAINDER OF THE WATERS THIS
MORNING...AND CONTINUING INTO THIS EVENING.
A GRADUAL SLACKENING OF THE GRADIENT EXPECTED LATE TONIGHT INTO
THU AS SURFACE WAVE DISSIPATES AND HIGH PRESSURE SLIDES FURTHER
OFFSHORE. THIS SHOULD ALLOW GALE CONDITIONS TO FALL TO SCA ON THE
OCEAN LATE THIS EVENING. SCA WINDS LIKELY CONTINUE ON THE OCEAN
WATERS THRU THU...BUT LOWER CONFIDENCE ON THE NEARSHORE WATERS
SEEING SCA CONDITIONS CONTINUE ON THU.
OCEAN SEAS EXPECTED TO BUILD TO 6 TO 10 FT WITH LONG PERIOD EASTERLY
SWELLS TODAY INTO TONIGHT...AND LIKELY SLOW TO SUBSIDE ON THU.
SCA CONDITIONS FORECAST ON THE OCEAN MUCH OF THE PERIOD THURSDAY
NIGHT THROUGH SATURDAY NIGHT. SCA CONDITIONS FORECAST FOR ALL WATERS
SATURDAY. SUB SCA CONDITIONS FORECAST OVERALL FOR SUNDAY.
&&
.HYDROLOGY...
RAINFALL OF 1/10 TO 2/10 INCH EXPECTED THROUGH THU. RAINFALL OF
AROUND 1/2 INCH LIKELY THU NIGHT THROUGH FRI NIGHT.
HYDROLOGIC IMPACTS NOT EXPECTED.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEB SITE.
&&
.TIDES/COASTAL FLOODING...
NE WINDS OF 15-25 KT TODAY INTO TONIGHT WILL HAVE WATER LEVELS
APPROACHING MINOR FLOODING LEVELS ACROSS THE MOST VULNERABLE AREAS
OF THE WESTERN GREAT SOUTH BAY DURING THE LATE TONIGHT HIGH TIDE
CYCLE. THERE IS A LOW PROBABILITY THAT MINOR FLOODING THRESHOLDS
ARE TOUCHED IN THESE AREAS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ338.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR ANZ330-335-
340-345.
GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR ANZ350-353-355.
&&
$$
SYNOPSIS...GOODMAN/NV
NEAR TERM...GOODMAN/NV
SHORT TERM...NV
LONG TERM...JM
AVIATION...BC
MARINE...GOODMAN/JM/NV
HYDROLOGY...GOODMAN/JM/NV
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
553 PM CDT WED APR 8 2015
.UPDATE...
547 PM CDT
I ADDED A DENSE FOG ADVISORY FOR LAKE AND COOK COUNTIES IN
ILLINOIS AS DENSE FOG HAS DEVELOPED NEAR THE LAKE SHORES. IT IS
POSSIBLE THIS DENSE FOG COULD DEVELOP FARTHER INLAND THROUGH THE
EVENING. IT IS EVEN POSSIBLE THAT FOG COULD OVERSPREAD MUCH OF
NORTHERN ILLINOIS TONIGHT AS A WARM FRONT AND HIGH DEW POINT AIR
BEGINS TO SLOWLY SHIFT NORTHWARD INTO THE COLDER AIRMASS ACROSS
NORTHERN ILLINOIS. CONFIDENCE REMAINS LOW ON THE EXTENT OF INLAND
DEVELOPMENT OF THIS FOG...HOWEVER...AS SHOWERS AND THUNDERSTORM
ACTIVITY COULD DIMINISH THE EXTENT OF FOG COVERAGE OVERNIGHT.
SO...WE WILL CONTINUE TO MONITOR THIS THREAT THROUGH THE EVENING.
KJB
&&
.SHORT TERM...
322 PM CDT
THROUGH THURSDAY NIGHT...
QUITE THE CHALLENGING SHORT TERM FORECAST WITH SEVERE WEATHER
POSSIBILITIES THROUGHOUT THE TIME AND PROBABLE RAPIDLY SOARING
TEMPERATURES FOR THE WHOLE AREA FIRST THING FRIDAY MORNING. THE
MAIN TIME FOR POSSIBLE SURFACE-BASED SEVERE WEATHER...INCLUDING
WIND AND POSSIBLE TORNADO CONCERNS...CONTINUES TO BE
MID-AFTERNOON THROUGH EARLY EVENING ON THURSDAY.
THE SURFACE WARM FRONT IS DRAPED ACROSS CENTRAL ILLINOIS AS OF 3
PM...INCLUDING INTO THE FAR SOUTHERN FORECAST AREA. A 1011MB
SURFACE LOW REFLECTION IS SEEN IN THE WIND ALONG THIS NEAR
DECATUR/CHAMPAIGN...WITH FESTERING NEAR OR SURFACE BASED STORMS
JUST AHEAD OF THIS NEAR THE I-74 CORRIDOR OCCASIONALLY PULSING
WITH HIGHER CORES. SATELLITE IMAGERY AND RAP ANALYSIS INDICATES
THE LIKELY PRESENCE OF VERY SUBTLE MID-LEVEL IMPULSES ACROSS
IA/IL/NORTHERN MO...ALL AHEAD OF AN INCREASING UPPER JET NOSING
EASTWARD INTO THE OZARK REGION THIS AFTERNOON.
IT IS ANTICIPATED THAT THESE PESKY MID-LEVEL FEATURES WILL
CONTINUE TO TRAVERSE ACROSS THE AREA THROUGH TONIGHT AND THURSDAY
MORNING WITH OVERALL UPPER SUPPORT FOR LIFT GRADUALLY IMPROVING.
ONE PROBLEM FOR RAPIDLY INCREASING CONVECTIVE COVERAGE THIS
EVENING IS THAT THE STRONGER LOW-LEVEL JET AND MOISTURE TRANSPORT
LOOK TO NOT ARRIVE UNTIL LATER INTO THE EVENING AND
OVERNIGHT...WHICH SEEMS NECESSARY TO TAP THE ELEVATED MIXED
LAYER/VERY STEEP ELEVATED LAPSE RATES FOR MORE WIDESPREAD AND
STRONGER CONVECTION. ALSO...STORMS ACROSS THE OZARKS INTO MO AND
SW IL MAY LIMIT THE EFFECTIVENESS OF MOISTURE TRANSPORT INTO OUR
AREA...AT LEAST AT FIRST THIS EVENING. A FURTHER HINDRANCE TO
CONFIDENCE FOR TONIGHT IS THAT CONVECTIVE-ALLOWING MODELS HAVE
REALLY STRUGGLED AND DIVERGED WITH HOW TONIGHT WILL PAN OUT FOR
STORM COVERAGE. HAVE GONE WITH THE THOUGHT LATER THIS EVENING INTO
OVERNIGHT/EARLY THURSDAY MORNING WITH HIGHER LIKELIHOOD FOR
STORMS...BUT CERTAINLY CANNOT RULE OUT SCATTERED EVENING ACTIVITY
WITHIN THE BROAD WARM ADVECTIVE ZONE. GIVEN THE AFOREMENTIONED
LAPSE RATES AND HIGH LEVELS OF CAPE IN THE HAIL GROWTH
ZONE...LARGE HAIL WILL CONTINUE TO BE THE MOST PROBABLE
THREAT...WITH ANY WIND THREATS REALLY SOUTH OF I-80...IF NOT EVEN
SOUTH OF U.S. HIGHWAY 24.
AS THE MAIN UPPER TROUGH EJECTS INTO THE CENTRAL PLAINS
OVERNIGHT...THE SURFACE RESPONSE SHOULD ALLOW THE WARM FRONT TO
CREEP NORTHWARD...AND MAYBE AT A QUICK RATE IF NOT MUCH CONVECTION
IS PRESENT. TEMPERATURES WILL THEN WARM AND QUITE QUICKLY WITH THE
FRONT PASSAGE...ALLOWING FOR TEMPERATURES TO SOAR INTO THE 70S
THURSDAY...EVEN WITH MORNING STORM ACTIVITY. AROUND 80 DEGREES IS
POSSIBLE JUST GIVEN OBSERVATION TRENDS TO OUR SOUTH TODAY.
THE WARM SECTOR IS LIKELY TO HAVE AT LEAST SOME ELEVATED STORMS
THROUGH THE MORNING AND MAYBE EVEN INTO THE AFTERNOON GIVEN THE
STEEP LAPSE RATES PRESENT. THIS WILL LIKELY HAVE SOME RESULT ON
REGENERATION/RE-INTENSIFICATION OF STORMS...BUT ITS POSSIBLE ANY
FESTERING ELEVATED STORMS ARE ABLE TO ROOT LOWER AS THE AFTERNOON
PROGRESSES AND BUOYANCY IMPROVES. THE SYNOPTIC PATTERN OF A
QUICKLY MOVING CLIMATOLOGICALLY COLD UPPER TROUGH ACROSS A WARM
SECTOR CHARACTERIZED BY EARLY APRIL DEW POINTS IN THE 60S
CERTAINLY FAVORS ORGANIZED STORM POTENTIAL...INCLUDING SUPERCELLS
WITH SIGNIFICANT SEVERE POTENTIAL...AS FURTHER VERIFIED BY
SEVERAL OF THE TOP MATCHING CIPS ANALOGS /SIMILAR SCENARIOS/.
HOWEVER...SEVERAL ANALOGS SHOW VERY LIMITED SEVERE WEATHER...AS
THE PRESENT INGREDIENTS JUST DID NOT LINE UP PERFECTLY AS CAN
OFTEN BE THE CASE IN MODERATE/STRONG DYNAMIC SITUATIONS. SO
CONFIDENCE REMAINS MINIMAL ON COVERAGE OF HIGHER INTENSITY
STORMS...BUT AT THIS JUNCTURE WOULD BE SURPRISED TO NOT HAVE AT
LEAST AN UPTICK IN LOWER ROOTED STORMS DURING THE MID-AFTERNOON
THROUGH EARLY EVENING PERIOD MOVING FROM WEST TO EAST ACROSS THE
AREA. WHILE THE NORTHERN CWA MAY HAVE MORE BACKED LOW-LEVEL
FLOW...THE ENTIRE AREA WILL BE UNDER A STRONG SSW 50-55 KT LOW-
LEVEL JET WHICH WOULD KEEP SOME THREATS OF SURFACE BASED
CONVECTION THROUGH THE EVENING AHEAD OF THE FRONT. HAIL WILL
REMAIN THE GREATEST CONCERN...ESPECIALLY WITH THE AFTERNOON
ACTIVITY...BUT SOME ORGANIZED STRONG WINDS OR TORNADOES IN THE
REGION ARE POSSIBLE DEPENDING ON STORM MODE/COVERAGE.
STORMS SHOULD BE EAST OF THE AREA BY 9 PM-12 AM THURSDAY EVENING
WITH COOLER AND DRIER AIR WRAPPING IN ON GUSTY WESTERLY WINDS.
MTF
&&
.LONG TERM...
FRIDAY THROUGH SATURDAY... FORECAST CONFIDENCE HIGH.
A POTENT SHORTWAVE WILL ROLL THROUGH SOUTHERN WI ON FRIDAY. THE
CYCLONIC FLOW AND STEEP LOW LEVEL LAPSE RATES WILL LEAD TO PLENTY OF
DIURNAL CUMULUS CLOUDS. A FEW SHOWERS ARE POSSIBLE TOWARD NORTHEAST
IL CLOSER TO THE VORTICITY MAXIMUM.
SURFACE HIGH PRESSURE WILL SPREAD INTO THE MIDWEST FRIDAY NIGHT
THROUGH SATURDAY AND BRING QUIET WEATHER. CLEAR SKIES FRIDAY NIGHT
WILL ALLOW TEMPS TO DROP INTO THE LOWER TO MID 30S... COLDEST NEAR
THE WI BORDER. TEMPERATURES SHOULD REBOUND INTO THE LOWER 60S
SATURDAY WITH WEAK WARM AIR ADVECTION OVER THE AREA.
SUNDAY... FORECAST CONFIDENCE HIGH.
SOUTHERLY WINDS WILL INCREASE AHEAD OF A MID LEVEL SHORTWAVE AND AN
ASSOCIATED SURFACE LOW PRESSURE TROUGH SWINGING THROUGH THE UPPER
MIDWEST AND GREAT LAKES REGION. LOW LEVELS ARE EXPECTED TO BE DRY...
SO NO PRECIP IS ANTICIPATED ACROSS NORTHEAST IL DURING THE DAY.
LIGHT SHOWERS WILL BE POSSIBLE SUNDAY NIGHT AS THE SURFACE TROUGH
PASSES THROUGH THE AREA. MODELS SOUNDINGS SHOW MINIMAL INSTABILITY
SO I LEFT OUT THUNDER.
MONDAY THROUGH TUESDAY... FORECAST CONFIDENCE MEDIUM.
MODELS ARE SLOWING DOWN THE SPEED OF THE WARM FRONTAL PRECIP INTO
CENTRAL IL ON MONDAY. THUS... CHANCES FOR SHOWERS AND THUNDERSTORMS
ARE DECREASING. BY MONDAY NIGHT... THE WARM FRONT WILL MAKE IT INTO
EITHER NORTHERN IL OR SOUTHERN WI. THIS WILL ALLOW FOR A BETTER
CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS THE FORECAST AREA
THROUGH TUESDAY NIGHT. THERE IS A POSSIBILITY FOR SEVERE WITH THIS
SYSTEM AND IT WILL NEED TO BE WATCHED.
MRC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* VFR VSBY THIS AFTERNOON TO LOWER BACK TO IFR TO MVFR AFTER
SUNSET THIS EVENING WITH FOG
* MVFR TO VFR CIGS LIKELY TO GO BACK TO IFR AFTER SUNSET
* SCATTERED THUNDERSTORMS DEVELOPING LATE THIS EVENING AND
ESPECIALLY OVERNIGHT AND DIMINISHING DURING MID AND LATE THU
MORNING.
* LIFR VIS/CIGS POSSIBLE TONIGHT...IMPROVING DURING MID/LATE
THURSDAY MORNING AS WARM FRONT LIFTS NORTH ACROSS AREA.
KMH/EJL
//DISCUSSION...UPDATED 18Z...
CIGS/VIS SHOULD CONTINUE TO SLOWLY IMPROVE THIS AFTERNOON WITH MVFR
CIGS AND VSBYS DEVELOPING. CIGS/VIS COULD POSSIBLY LOWER BACK TO IFR
OR EVEN LIFR AFTER SUNSET THIS EVENING INTO OVERNIGHT BUT CONFIDENCE
IS LOW.
COMPLEX OF SHOWERS AND THUNDERSTORMS ACROSS SW HALF OF IL WILL TRACK
ENE AND INITIALLY STAY SOUTH OF CHICAGO AREA THIS AFTERNOON INTO
MID EVENING. FOCUS SHIFTS TO COMPLEX OF MORE THUNDERSTORMS TO
DEVELOP OVER MO AND TRACK NE INTO NE IL LATE THIS EVENING OR
OVERNIGHT AND THEN DIMINISH DURING MID/LATE THU MORNING AS WARM
FRONT LIFTS NORTH OF AREA. CONFIDENCE REGARDING
TIMING/LOCATION/COVERAGE IS LOW TO MEDIUM AND OPTED TO CONTINUE
WITH A LONGER DURATION OF VICINITY THUNDER FROM 05-09Z WITH HIGHER
COVERAGE OF SHOWERS AND THUNDERSTORMS FROM 09-15Z.
GENERALLY NORTHEAST WINDS 5-10 KTS WILL CONTINUE THRU THIS EVENING
WINDS WILL BEGIN TO TURN SOUTHEAST DURING OVERNIGHT...THEN MORE SOUTH
SOUTHWEST AND INCREASE TO 10-15 KTS AND GUSTS NEAR 20 KTS LATER THURSDAY
MORNING AND THU AFTERNOON AS A WARM FRONT LIFTS THROUGH THE TERMINALS THU
MORNING. WHEN THIS OCCURS...EXPECT RAPID IMPROVEMENT THROUGH
MVFR CIGS AND LIKELY TO PREVAILING VFR CIGS...OUTSIDE PRECIP...LATER THU
MORNING.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN CIGS/VSBY LOWERING THIS EVENING AFTER SUNSET WITH
FOG
* MEDIUM TO HIGH IN WINDS THROUGH THE PERIOD.
* MEDIUM CONFIDENCE IN TS FROM LATE EVENING INTO THU MORNING...LOW TO
MEDIUM FOR TIMING AND COVERAGE.
KMH/EJL
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
* THURSDAY NIGHT...STRONG TSRA IN THE EVENING. MVFR POSSIBLE.
STRONG/GUSTY SOUTHWEST WINDS BECOMING WEST.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...SLIGHT CHANCE OF SHRA. SOUTH WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. SOUTHWEST WINDS.
* TUESDAY...CHANCE OF SHRA. SOUTHWEST WINDS.
&&
.MARINE...
333 PM... AN INCREASING SURFACE PRESSURE GRADIENT IS LEADING TO NNE
WINDS OF 15 TO 20 MPH WITH A FEW HIGHER GUSTS THIS AFTERNOON OVER
SOUTHERN LAKE MICHIGAN. THERE IS ALSO A FAVORABLE FETCH FOR HIGH
WAVES IN THE NEARSHORE ZONES. EXPECT THIS TO PERSIST THROUGH LATE
TONIGHT.
WESTERLY WINDS IN THE WAKE OF A STRONG LOW PRESSURE SYSTEM WILL
BRING GUSTY WINDS TO ALL OF LAKE MICHIGAN THURSDAY NIGHT THROUGH
FRIDAY. GALE FORCE GUSTS TO 35 KNOTS OVER THE OPEN WATERS OF
SOUTHERN LAKE MICHIGAN ARE POSSIBLE.
BREEZY SOUTH WINDS ARE EXPECTED ON SUNDAY AS HIGH PRESSURE SHIFTS
EAST OF LAKE MICHIGAN. WIND GUSTS SHOULD REMAIN BELOW GALE FORCE...
BUT SMALL CRAFT CONDITIONS MAY BE MET OVER THE NEARSHORE WATERS OF
NORTHEAST IL. MRC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...DENSE FOG ADVISORY...ILZ006-ILZ014 UNTIL 9 AM THURSDAY.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 10 PM
WEDNESDAY.
DENSE FOG ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 10 PM WEDNESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
PORTION ISSUED BY NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
333 PM CDT WED APR 8 2015
.SHORT TERM...
322 PM CDT
THROUGH THURSDAY NIGHT...
QUITE THE CHALLENGING SHORT TERM FORECAST WITH SEVERE WEATHER
POSSIBILITIES THROUGHOUT THE TIME AND PROBABLE RAPIDLY SOARING
TEMPERATURES FOR THE WHOLE AREA FIRST THING FRIDAY MORNING. THE
MAIN TIME FOR POSSIBLE SURFACE-BASED SEVERE WEATHER...INCLUDING
WIND AND POSSIBLE TORNADO CONCERNS...CONTINUES TO BE
MID-AFTERNOON THROUGH EARLY EVENING ON THURSDAY.
THE SURFACE WARM FRONT IS DRAPED ACROSS CENTRAL ILLINOIS AS OF 3
PM...INCLUDING INTO THE FAR SOUTHERN FORECAST AREA. A 1011MB
SURFACE LOW REFLECTION IS SEEN IN THE WIND ALONG THIS NEAR
DECATUR/CHAMPAIGN...WITH FESTERING NEAR OR SURFACE BASED STORMS
JUST AHEAD OF THIS NEAR THE I-74 CORRIDOR OCCASIONALLY PULSING
WITH HIGHER CORES. SATELLITE IMAGERY AND RAP ANALYSIS INDICATES
THE LIKELY PRESENCE OF VERY SUBTLE MID-LEVEL IMPULSES ACROSS
IA/IL/NORTHERN MO...ALL AHEAD OF AN INCREASING UPPER JET NOSING
EASTWARD INTO THE OZARK REGION THIS AFTERNOON.
IT IS ANTICIPATED THAT THESE PESKY MID-LEVEL FEATURES WILL
CONTINUE TO TRAVERSE ACROSS THE AREA THROUGH TONIGHT AND THURSDAY
MORNING WITH OVERALL UPPER SUPPORT FOR LIFT GRADUALLY IMPROVING.
ONE PROBLEM FOR RAPIDLY INCREASING CONVECTIVE COVERAGE THIS
EVENING IS THAT THE STRONGER LOW-LEVEL JET AND MOISTURE TRANSPORT
LOOK TO NOT ARRIVE UNTIL LATER INTO THE EVENING AND
OVERNIGHT...WHICH SEEMS NECESSARY TO TAP THE ELEVATED MIXED
LAYER/VERY STEEP ELEVATED LAPSE RATES FOR MORE WIDESPREAD AND
STRONGER CONVECTION. ALSO...STORMS ACROSS THE OZARKS INTO MO AND
SW IL MAY LIMIT THE EFFECTIVENESS OF MOISTURE TRANSPORT INTO OUR
AREA...AT LEAST AT FIRST THIS EVENING. A FURTHER HINDRANCE TO
CONFIDENCE FOR TONIGHT IS THAT CONVECTIVE-ALLOWING MODELS HAVE
REALLY STRUGGLED AND DIVERGED WITH HOW TONIGHT WILL PAN OUT FOR
STORM COVERAGE. HAVE GONE WITH THE THOUGHT LATER THIS EVENING INTO
OVERNIGHT/EARLY THURSDAY MORNING WITH HIGHER LIKELIHOOD FOR
STORMS...BUT CERTAINLY CANNOT RULE OUT SCATTERED EVENING ACTIVITY
WITHIN THE BROAD WARM ADVECTIVE ZONE. GIVEN THE AFOREMENTIONED
LAPSE RATES AND HIGH LEVELS OF CAPE IN THE HAIL GROWTH
ZONE...LARGE HAIL WILL CONTINUE TO BE THE MOST PROBABLE
THREAT...WITH ANY WIND THREATS REALLY SOUTH OF I-80...IF NOT EVEN
SOUTH OF U.S. HIGHWAY 24.
AS THE MAIN UPPER TROUGH EJECTS INTO THE CENTRAL PLAINS
OVERNIGHT...THE SURFACE RESPONSE SHOULD ALLOW THE WARM FRONT TO
CREEP NORTHWARD...AND MAYBE AT A QUICK RATE IF NOT MUCH CONVECTION
IS PRESENT. TEMPERATURES WILL THEN WARM AND QUITE QUICKLY WITH THE
FRONT PASSAGE...ALLOWING FOR TEMPERATURES TO SOAR INTO THE 70S
THURSDAY...EVEN WITH MORNING STORM ACTIVITY. AROUND 80 DEGREES IS
POSSIBLE JUST GIVEN OBSERVATION TRENDS TO OUR SOUTH TODAY.
THE WARM SECTOR IS LIKELY TO HAVE AT LEAST SOME ELEVATED STORMS
THROUGH THE MORNING AND MAYBE EVEN INTO THE AFTERNOON GIVEN THE
STEEP LAPSE RATES PRESENT. THIS WILL LIKELY HAVE SOME RESULT ON
REGENERATION/RE-INTENSIFICATION OF STORMS...BUT ITS POSSIBLE ANY
FESTERING ELEVATED STORMS ARE ABLE TO ROOT LOWER AS THE AFTERNOON
PROGRESSES AND BUOYANCY IMPROVES. THE SYNOPTIC PATTERN OF A
QUICKLY MOVING CLIMATOLOGICALLY COLD UPPER TROUGH ACROSS A WARM
SECTOR CHARACTERIZED BY EARLY APRIL DEW POINTS IN THE 60S
CERTAINLY FAVORS ORGANIZED STORM POTENTIAL...INCLUDING SUPERCELLS
WITH SIGNIFICANT SEVERE POTENTIAL...AS FURTHER VERIFIED BY
SEVERAL OF THE TOP MATCHING CIPS ANALOGS /SIMILAR SCENARIOS/.
HOWEVER...SEVERAL ANALOGS SHOW VERY LIMITED SEVERE WEATHER...AS
THE PRESENT INGREDIENTS JUST DID NOT LINE UP PERFECTLY AS CAN
OFTEN BE THE CASE IN MODERATE/STRONG DYNAMIC SITUATIONS. SO
CONFIDENCE REMAINS MINIMAL ON COVERAGE OF HIGHER INTENSITY
STORMS...BUT AT THIS JUNCTURE WOULD BE SURPRISED TO NOT HAVE AT
LEAST AN UPTICK IN LOWER ROOTED STORMS DURING THE MID-AFTERNOON
THROUGH EARLY EVENING PERIOD MOVING FROM WEST TO EAST ACROSS THE
AREA. WHILE THE NORTHERN CWA MAY HAVE MORE BACKED LOW-LEVEL
FLOW...THE ENTIRE AREA WILL BE UNDER A STRONG SSW 50-55 KT LOW-
LEVEL JET WHICH WOULD KEEP SOME THREATS OF SURFACE BASED
CONVECTION THROUGH THE EVENING AHEAD OF THE FRONT. HAIL WILL
REMAIN THE GREATEST CONCERN...ESPECIALLY WITH THE AFTERNOON
ACTIVITY...BUT SOME ORGANIZED STRONG WINDS OR TORNADOES IN THE
REGION ARE POSSIBLE DEPENDING ON STORM MODE/COVERAGE.
STORMS SHOULD BE EAST OF THE AREA BY 9 PM-12 AM THURSDAY EVENING
WITH COOLER AND DRIER AIR WRAPPING IN ON GUSTY WESTERLY WINDS.
MTF
&&
.LONG TERM...
FRIDAY THROUGH SATURDAY... FORECAST CONFIDENCE HIGH.
A POTENT SHORTWAVE WILL ROLL THROUGH SOUTHERN WI ON FRIDAY. THE
CYCLONIC FLOW AND STEEP LOW LEVEL LAPSE RATES WILL LEAD TO PLENTY OF
DIURNAL CUMULUS CLOUDS. A FEW SHOWERS ARE POSSIBLE TOWARD NORTHEAST
IL CLOSER TO THE VORTICITY MAXIMUM.
SURFACE HIGH PRESSURE WILL SPREAD INTO THE MIDWEST FRIDAY NIGHT
THROUGH SATURDAY AND BRING QUIET WEATHER. CLEAR SKIES FRIDAY NIGHT
WILL ALLOW TEMPS TO DROP INTO THE LOWER TO MID 30S... COLDEST NEAR
THE WI BORDER. TEMPERATURES SHOULD REBOUND INTO THE LOWER 60S
SATURDAY WITH WEAK WARM AIR ADVECTION OVER THE AREA.
SUNDAY... FORECAST CONFIDENCE HIGH.
SOUTHERLY WINDS WILL INCREASE AHEAD OF A MID LEVEL SHORTWAVE AND AN
ASSOCIATED SURFACE LOW PRESSURE TROUGH SWINGING THROUGH THE UPPER
MIDWEST AND GREAT LAKES REGION. LOW LEVELS ARE EXPECTED TO BE DRY...
SO NO PRECIP IS ANTICIPATED ACROSS NORTHEAST IL DURING THE DAY.
LIGHT SHOWERS WILL BE POSSIBLE SUNDAY NIGHT AS THE SURFACE TROUGH
PASSES THROUGH THE AREA. MODELS SOUNDINGS SHOW MINIMAL INSTABILITY
SO I LEFT OUT THUNDER.
MONDAY THROUGH TUESDAY... FORECAST CONFIDENCE MEDIUM.
MODELS ARE SLOWING DOWN THE SPEED OF THE WARM FRONTAL PRECIP INTO
CENTRAL IL ON MONDAY. THUS... CHANCES FOR SHOWERS AND THUNDERSTORMS
ARE DECREASING. BY MONDAY NIGHT... THE WARM FRONT WILL MAKE IT INTO
EITHER NORTHERN IL OR SOUTHERN WI. THIS WILL ALLOW FOR A BETTER
CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS THE FORECAST AREA
THROUGH TUESDAY NIGHT. THERE IS A POSSIBILITY FOR SEVERE WITH THIS
SYSTEM AND IT WILL NEED TO BE WATCHED.
MRC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* VFR VSBY THIS AFTERNOON TO LOWER BACK TO IFR TO MVFR AFTER
SUNSET THIS EVENING WITH FOG
* MVFR TO VFR CIGS LIKELY TO GO BACK TO IFR AFTER SUNSET
* SCATTERED THUNDERSTORMS DEVELOPING LATE THIS EVENING AND
ESPECIALLY OVERNIGHT AND DIMINISHING DURING MID AND LATE THU
MORNING.
* LIFR VIS/CIGS POSSIBLE TONIGHT...IMPROVING DURING MID/LATE
THURSDAY MORNING AS WARM FRONT LIFTS NORTH ACROSS AREA.
KMH/EJL
//DISCUSSION...UPDATED 18Z...
CIGS/VIS SHOULD CONTINUE TO SLOWLY IMPROVE THIS AFTERNOON WITH MVFR
CIGS AND VSBYS DEVELOPING. CIGS/VIS COULD POSSIBLY LOWER BACK TO IFR
OR EVEN LIFR AFTER SUNSET THIS EVENING INTO OVERNIGHT BUT CONFIDENCE
IS LOW.
COMPLEX OF SHOWERS AND THUNDERSTORMS ACROSS SW HALF OF IL WILL TRACK
ENE AND INITIALLY STAY SOUTH OF CHICAGO AREA THIS AFTERNOON INTO
MID EVENING. FOCUS SHIFTS TO COMPLEX OF MORE THUNDERSTORMS TO
DEVELOP OVER MO AND TRACK NE INTO NE IL LATE THIS EVENING OR
OVERNIGHT AND THEN DIMINISH DURING MID/LATE THU MORNING AS WARM
FRONT LIFTS NORTH OF AREA. CONFIDENCE REGARDING
TIMING/LOCATION/COVERAGE IS LOW TO MEDIUM AND OPTED TO CONTINUE
WITH A LONGER DURATION OF VICINITY THUNDER FROM 05-09Z WITH HIGHER
COVERAGE OF SHOWERS AND THUNDERSTORMS FROM 09-15Z.
GENERALLY NORTHEAST WINDS 5-10 KTS WILL CONTINUE THRU THIS EVENING
WINDS WILL BEGIN TO TURN SOUTHEAST DURING OVERNIGHT...THEN MORE SOUTH
SOUTHWEST AND INCREASE TO 10-15 KTS AND GUSTS NEAR 20 KTS LATER THURSDAY
MORNING AND THU AFTERNOON AS A WARM FRONT LIFTS THROUGH THE TERMINALS THU
MORNING. WHEN THIS OCCURS...EXPECT RAPID IMPROVEMENT THROUGH
MVFR CIGS AND LIKELY TO PREVAILING VFR CIGS...OUTSIDE PRECIP...LATER THU
MORNING.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN CIGS/VSBY LOWERING THIS EVENING AFTER SUNSET WITH
FOG
* MEDIUM TO HIGH IN WINDS THROUGH THE PERIOD.
* MEDIUM CONFIDENCE IN TS FROM LATE EVENING INTO THU MORNING...LOW TO
MEDIUM FOR TIMING AND COVERAGE.
KMH/EJL
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
* THURSDAY NIGHT...STRONG TSRA IN THE EVENING. MVFR POSSIBLE.
STRONG/GUSTY SOUTHWEST WINDS BECOMING WEST.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...SLIGHT CHANCE OF SHRA. SOUTH WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. SOUTHWEST WINDS.
* TUESDAY...CHANCE OF SHRA. SOUTHWEST WINDS.
&&
.MARINE...
333 PM... AN INCREASING SURFACE PRESSURE GRADIENT IS LEADING TO NNE
WINDS OF 15 TO 20 MPH WITH A FEW HIGHER GUSTS THIS AFTERNOON OVER
SOUTHERN LAKE MICHIGAN. THERE IS ALSO A FAVORABLE FETCH FOR HIGH
WAVES IN THE NEARSHORE ZONES. EXPECT THIS TO PERSIST THROUGH LATE
TONIGHT.
WESTERLY WINDS IN THE WAKE OF A STRONG LOW PRESSURE SYSTEM WILL
BRING GUSTY WINDS TO ALL OF LAKE MICHIGAN THURSDAY NIGHT THROUGH
FRIDAY. GALE FORCE GUSTS TO 35 KNOTS OVER THE OPEN WATERS OF
SOUTHERN LAKE MICHIGAN ARE POSSIBLE.
BREEZY SOUTH WINDS ARE EXPECTED ON SUNDAY AS HIGH PRESSURE SHIFTS
EAST OF LAKE MICHIGAN. WIND GUSTS SHOULD REMAIN BELOW GALE FORCE...
BUT SMALL CRAFT CONDITIONS MAY BE MET OVER THE NEARSHORE WATERS OF
NORTHEAST IL. MRC
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 5 AM
THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
329 PM CDT WED APR 8 2015
.SHORT TERM...
322 PM CDT
THROUGH THURSDAY NIGHT...
QUITE THE CHALLENGING SHORT TERM FORECAST WITH SEVERE WEATHER
POSSIBILITIES THROUGHOUT THE TIME AND PROBABLE RAPIDLY SOARING
TEMPERATURES FOR THE WHOLE AREA FIRST THING FRIDAY MORNING. THE
MAIN TIME FOR POSSIBLE SURFACE-BASED SEVERE WEATHER...INCLUDING
WIND AND POSSIBLE TORNADO CONCERNS...CONTINUES TO BE
MID-AFTERNOON THROUGH EARLY EVENING ON THURSDAY.
THE SURFACE WARM FRONT IS DRAPED ACROSS CENTRAL ILLINOIS AS OF 3
PM...INCLUDING INTO THE FAR SOUTHERN FORECAST AREA. A 1011MB
SURFACE LOW REFLECTION IS SEEN IN THE WIND ALONG THIS NEAR
DECATUR/CHAMPAIGN...WITH FESTERING NEAR OR SURFACE BASED STORMS
JUST AHEAD OF THIS NEAR THE I-74 CORRIDOR OCCASIONALLY PULSING
WITH HIGHER CORES. SATELLITE IMAGERY AND RAP ANALYSIS INDICATES
THE LIKELY PRESENCE OF VERY SUBTLE MID-LEVEL IMPULSES ACROSS
IA/IL/NORTHERN MO...ALL AHEAD OF AN INCREASING UPPER JET NOSING
EASTWARD INTO THE OZARK REGION THIS AFTERNOON.
IT IS ANTICIPATED THAT THESE PESKY MID-LEVEL FEATURES WILL
CONTINUE TO TRAVERSE ACROSS THE AREA THROUGH TONIGHT AND THURSDAY
MORNING WITH OVERALL UPPER SUPPORT FOR LIFT GRADUALLY IMPROVING.
ONE PROBLEM FOR RAPIDLY INCREASING CONVECTIVE COVERAGE THIS
EVENING IS THAT THE STRONGER LOW-LEVEL JET AND MOISTURE TRANSPORT
LOOK TO NOT ARRIVE UNTIL LATER INTO THE EVENING AND
OVERNIGHT...WHICH SEEMS NECESSARY TO TAP THE ELEVATED MIXED
LAYER/VERY STEEP ELEVATED LAPSE RATES FOR MORE WIDESPREAD AND
STRONGER CONVECTION. ALSO...STORMS ACROSS THE OZARKS INTO MO AND
SW IL MAY LIMIT THE EFFECTIVENESS OF MOISTURE TRANSPORT INTO OUR
AREA...AT LEAST AT FIRST THIS EVENING. A FURTHER HINDRANCE TO
CONFIDENCE FOR TONIGHT IS THAT CONVECTIVE-ALLOWING MODELS HAVE
REALLY STRUGGLED AND DIVERGED WITH HOW TONIGHT WILL PAN OUT FOR
STORM COVERAGE. HAVE GONE WITH THE THOUGHT LATER THIS EVENING INTO
OVERNIGHT/EARLY THURSDAY MORNING WITH HIGHER LIKELIHOOD FOR
STORMS...BUT CERTAINLY CANNOT RULE OUT SCATTERED EVENING ACTIVITY
WITHIN THE BROAD WARM ADVECTIVE ZONE. GIVEN THE AFOREMENTIONED
LAPSE RATES AND HIGH LEVELS OF CAPE IN THE HAIL GROWTH
ZONE...LARGE HAIL WILL CONTINUE TO BE THE MOST PROBABLE
THREAT...WITH ANY WIND THREATS REALLY SOUTH OF I-80...IF NOT EVEN
SOUTH OF U.S. HIGHWAY 24.
AS THE MAIN UPPER TROUGH EJECTS INTO THE CENTRAL PLAINS
OVERNIGHT...THE SURFACE RESPONSE SHOULD ALLOW THE WARM FRONT TO
CREEP NORTHWARD...AND MAYBE AT A QUICK RATE IF NOT MUCH CONVECTION
IS PRESENT. TEMPERATURES WILL THEN WARM AND QUITE QUICKLY WITH THE
FRONT PASSAGE...ALLOWING FOR TEMPERATURES TO SOAR INTO THE 70S
THURSDAY...EVEN WITH MORNING STORM ACTIVITY. AROUND 80 DEGREES IS
POSSIBLE JUST GIVEN OBSERVATION TRENDS TO OUR SOUTH TODAY.
THE WARM SECTOR IS LIKELY TO HAVE AT LEAST SOME ELEVATED STORMS
THROUGH THE MORNING AND MAYBE EVEN INTO THE AFTERNOON GIVEN THE
STEEP LAPSE RATES PRESENT. THIS WILL LIKELY HAVE SOME RESULT ON
REGENERATION/RE-INTENSIFICATION OF STORMS...BUT ITS POSSIBLE ANY
FESTERING ELEVATED STORMS ARE ABLE TO ROOT LOWER AS THE AFTERNOON
PROGRESSES AND BUOYANCY IMPROVES. THE SYNOPTIC PATTERN OF A
QUICKLY MOVING CLIMATOLOGICALLY COLD UPPER TROUGH ACROSS A WARM
SECTOR CHARACTERIZED BY EARLY APRIL DEW POINTS IN THE 60S
CERTAINLY FAVORS ORGANIZED STORM POTENTIAL...INCLUDING SUPERCELLS
WITH SIGNIFICANT SEVERE POTENTIAL...AS FURTHER VERIFIED BY
SEVERAL OF THE TOP MATCHING CIPS ANALOGS /SIMILAR SCENARIOS/.
HOWEVER...SEVERAL ANALOGS SHOW VERY LIMITED SEVERE WEATHER...AS
THE PRESENT INGREDIENTS JUST DID NOT LINE UP PERFECTLY AS CAN
OFTEN BE THE CASE IN MODERATE/STRONG DYNAMIC SITUATIONS. SO
CONFIDENCE REMAINS MINIMAL ON COVERAGE OF HIGHER INTENSITY
STORMS...BUT AT THIS JUNCTURE WOULD BE SURPRISED TO NOT HAVE AT
LEAST AN UPTICK IN LOWER ROOTED STORMS DURING THE MID-AFTERNOON
THROUGH EARLY EVENING PERIOD MOVING FROM WEST TO EAST ACROSS THE
AREA. WHILE THE NORTHERN CWA MAY HAVE MORE BACKED LOW-LEVEL
FLOW...THE ENTIRE AREA WILL BE UNDER A STRONG SSW 50-55 KT LOW-
LEVEL JET WHICH WOULD KEEP SOME THREATS OF SURFACE BASED
CONVECTION THROUGH THE EVENING AHEAD OF THE FRONT. HAIL WILL
REMAIN THE GREATEST CONCERN...ESPECIALLY WITH THE AFTERNOON
ACTIVITY...BUT SOME ORGANIZED STRONG WINDS OR TORNADOES IN THE
REGION ARE POSSIBLE DEPENDING ON STORM MODE/COVERAGE.
STORMS SHOULD BE EAST OF THE AREA BY 9 PM-12 AM THURSDAY EVENING
WITH COOLER AND DRIER AIR WRAPPING IN ON GUSTY WESTERLY WINDS.
MTF
&&
.LONG TERM...
TO BE ISSUED SHORTLY.
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* VFR VSBY THIS AFTERNOON TO LOWER BACK TO IFR TO MVFR AFTER
SUNSET THIS EVENING WITH FOG
* MVFR TO VFR CIGS LIKELY TO GO BACK TO IFR AFTER SUNSET
* SCATTERED THUNDERSTORMS DEVELOPING LATE THIS EVENING AND
ESPECIALLY OVERNIGHT AND DIMINISHING DURING MID AND LATE THU
MORNING.
* LIFR VIS/CIGS POSSIBLE TONIGHT...IMPROVING DURING MID/LATE
THURSDAY MORNING AS WARM FRONT LIFTS NORTH ACROSS AREA.
KMH/EJL
//DISCUSSION...UPDATED 18Z...
CIGS/VIS SHOULD CONTINUE TO SLOWLY IMPROVE THIS AFTERNOON WITH MVFR
CIGS AND VSBYS DEVELOPING. CIGS/VIS COULD POSSIBLY LOWER BACK TO IFR
OR EVEN LIFR AFTER SUNSET THIS EVENING INTO OVERNIGHT BUT CONFIDENCE
IS LOW.
COMPLEX OF SHOWERS AND THUNDERSTORMS ACROSS SW HALF OF IL WILL TRACK
ENE AND INITIALLY STAY SOUTH OF CHICAGO AREA THIS AFTERNOON INTO
MID EVENING. FOCUS SHIFTS TO COMPLEX OF MORE THUNDERSTORMS TO
DEVELOP OVER MO AND TRACK NE INTO NE IL LATE THIS EVENING OR
OVERNIGHT AND THEN DIMINISH DURING MID/LATE THU MORNING AS WARM
FRONT LIFTS NORTH OF AREA. CONFIDENCE REGARDING
TIMING/LOCATION/COVERAGE IS LOW TO MEDIUM AND OPTED TO CONTINUE
WITH A LONGER DURATION OF VICINITY THUNDER FROM 05-09Z WITH HIGHER
COVERAGE OF SHOWERS AND THUNDERSTORMS FROM 09-15Z.
GENERALLY NORTHEAST WINDS 5-10 KTS WILL CONTINUE THRU THIS EVENING
WINDS WILL BEGIN TO TURN SOUTHEAST DURING OVERNIGHT...THEN MORE SOUTH
SOUTHWEST AND INCREASE TO 10-15 KTS AND GUSTS NEAR 20 KTS LATER THURSDAY
MORNING AND THU AFTERNOON AS A WARM FRONT LIFTS THROUGH THE TERMINALS THU
MORNING. WHEN THIS OCCURS...EXPECT RAPID IMPROVEMENT THROUGH
MVFR CIGS AND LIKELY TO PREVAILING VFR CIGS...OUTSIDE PRECIP...LATER THU
MORNING.
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN CIGS/VSBY LOWERING THIS EVENING AFTER SUNSET WITH
FOG
* MEDIUM TO HIGH IN WINDS THROUGH THE PERIOD.
* MEDIUM CONFIDENCE IN TS FROM LATE EVENING INTO THU MORNING...LOW TO
MEDIUM FOR TIMING AND COVERAGE.
KMH/EJL
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
* THURSDAY NIGHT...STRONG TSRA IN THE EVENING. MVFR POSSIBLE.
STRONG/GUSTY SOUTHWEST WINDS BECOMING WEST.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...SLIGHT CHANCE OF SHRA. SOUTH WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. SOUTHWEST WINDS.
* TUESDAY...CHANCE OF SHRA. SOUTHWEST WINDS.
&&
.MARINE...
415 AM...A FRONTAL BOUNDARY WILL REMAIN STATIONARY JUST SOUTH OF
LAKE MICHIGAN INTO THIS EVENING...THEN BEGIN TO LIFT NORTH ACROSS
THE LAKE LATE TONIGHT AND THURSDAY AS A WARM FRONT AS LOW PRESSURE
OVER THE PLAINS MOVES NORTHEAST TONIGHT AND THURSDAY...REACHING
NORTHERN LAKE MICHIGAN BY FRIDAY MORNING. NORTHEAST WINDS WILL
REMAIN IN THE 20-25KT RANGE TODAY...WITH SOME HIGHER GUSTS
POSSIBLE. WINDS WILL SLOWLY DIMINISH LATE TONIGHT INTO THURSDAY
MORNING...THEN AS WINDS SHIFTING SOUTHWESTERLY THURSDAY AFTERNOON
AND ESPECIALLY THURSDAY EVENING...THEY WILL INCREASE TO 30 KT...
SHIFTING WESTERLY THURSDAY NIGHT AFTER A COLD FRONT MOVES ACROSS
THE LAKE. WINDS WILL SLOWLY DIMINISH FRIDAY AFTERNOON INTO FRIDAY
EVENING...THEN BECOME LIGHT SATURDAY AS HIGH PRESSURE MOVES ACROSS
THE REGION. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 5 AM
THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1249 PM CDT WED APR 8 2015
.MESOSCALE DISCUSSION...
1249 PM CDT
SURFACE BASED THUNDERSTORMS HAVE BEEN DEVELOPING AND GRADUALLY
INTENSIFYING OVER CENTRAL ILLINOIS ALONG THE LEADING EDGE OF THE
DECAYING MCS. MODIFYING ILX MORNING SOUNDING FOR CURRENT OBS AND
SPC OBJECTIVE MESOANALYSIS DATA SUGGEST MLCAPES NEARING 1000 J/KG
IN ADVANCE OF THESE STORMS WITH ONLY MODEST CONVECTIVE INHIBITION.
KILX WSR 88-D VWP WOULD SUGGEST 30-35KT OF 0-6KM BULK SHEAR WHICH
GIVEN THE INSTABILITY IS CERTAINLY SUFFICIENT FOR THESE STORMS TO
INTENSIFY AND POTENTIALLY GROW SEVERE THIS AFTERNOON. NOT TERRIBLY
CLEAR THE FORCING MECHANISM AND SFC WINDS ARE VEERS LESSENING LOW
LEVEL CONVERGENCE...BUT GIVEN RECENT RADAR TRENDS AND CAPE/SHEAR
WITH ONLY WEAK INHIBITION IT SEEMS REASONABLE STORMS WILL CONTINUE
AND POTENTIALLY INTENSIFY AS THEY PUSH EAST INTO OUR SOUTHERN MOST
CWA. DEEP LAYER SHEAR IS NOT OVERLY IMPRESSIVE...HOWEVER PROXIMITY
OF WARM FRONT DOES BEAR WATCHING AS SHOULD A CELL MANAGE TO ATTACH
ITSELF TO AND RIDE THE WARM FRONT EAST THE SUPERCELL AND ATTENDANT
SEVERE WEATHER POTENTIAL WOULD INCREASE.
IZZI
&&
.SHORT TERM...
347 AM CDT
THROUGH THURSDAY...
TODAY THROUGH FRIDAY NIGHT...
MAIN FOCUS IS ON PERIODS OF CONVECTION...PARTICULARLY THIS
MORNING ACROSS PART OF THE FORECAST AREAS...AND ACROSS THE ENTIRE
AREA TONIGHT INTO THURSDAY. SEVERE WEATHER THREAT REMAINS OF GREAT
CONCERN THURSDAY AFTERNOON AND EVENING.
EARLY MORNING SURFACE ANALYSIS DEPICTS LOW PRESSURE OVER
NORTHEASTERN MISSOURI...WITH AN INVERTED TROUGH EXTENDING
NORTHEAST ACROSS SOUTHEAST WI/LAKE MICHIGAN. THESE FEATURES APPEAR
TO BE ASSOCIATED WITH A COUPLE OF MID-LEVEL SHORT WAVE TROUGHS
PROPAGATING ACROSS THE REGION IN BROAD WEST-SOUTHWESTERLY FLOW
ALOFT. A CLUSTER OF THUNDERSTORMS HAD DEVELOPED ACROSS SOUTHEAST
IOWA LAST EVENING IN LOW LEVEL WARM/MOIST ADVECTION MAXIMA
NORTHEAST OF THE SURFACE LOW...AND CONTINUE TO PERSIST AND EXPAND
SLOWLY EASTWARD ACROSS PARTS OF ILLINOIS EARLY THIS MORNING ON 30
KT 925 MB JET AHEAD OF SHORT WAVE. THESE STORMS ARE LIKELY TO
CONTINUE TO DEVELOP EASTWARD ACROSS MAINLY THE SOUTHERN TWO THIRDS
OR SO OF THE CWA EARLY THIS MORNING AS THE SURFACE WAVE MOVE
THROUGH THE AREA. SPC MESOANALYSIS DATA INDICATES UPSTREAM AIR
MASS CHARACTERIZED BY STEEP MID-LEVEL LAPSE RATES IN EXCESS OF 7.5
C/KM YIELDING 1000-1500 J/KG OF ELEVATED MUCAPE...AND ROUGHLY
40-45 KT OF EFFECTIVE DEEP LAYER BULK SHEAR. SOME OF THE STRONGER
CORES MAY BE CAPABLE OF PRODUCING SOME MARGINAL HAIL THIS
MORNING...THOUGH AN OVERALL WEAKENING TREND IS EXPECTED AS THE LOW
LEVEL FLOW VEERS MORE WESTERLY AND DECREASES AND REDUCES LOW LEVEL
MOISTURE TRANSPORT/THETA-E ADVECTION ACROSS OUR SOUTH AND
SOUTHEAST COUNTIES. THIS TREND IS SUPPORTED BY HIGH-RES HRRR/RAP
GUIDANCE WHICH INDICATE ACTIVITY MOVING ACROSS THE AREA THROUGH
13-14Z.
MOIST/SATURATED LOW LEVEL AIR MASS HAS ALSO REDUCED VISIBILITY IN
FOG OVER THE PAST SEVERAL HOURS...WITH SOME PATCHES OF DENSE FOG
NOTED. MAY HAVE TO CONSIDER A HEADLINE...THOUGH MORNING SHOWERS
MAY HELP RAISE VISIBILITY SOMEWHAT AND WILL CONTINUE TO MONITOR.
NOT MUCH IS EXPECTED IN THE WAY OF ORGANIZED PRECIP FROM MID-
MORNING INTO THIS AFTERNOON...WITH PASSAGE OF THE SHORT WAVE AND
WEAKENING OF THE SURFACE WAVE ALONG THE FRONT TO OUR SOUTH. WEAK
BUT PERSISTENT SOUTHWEST FLOW WILL CONTINUE ABOVE THE SHALLOW COOL
BOUNDARY LAYER NORTH OF THE SURFACE FRONT...WHICH COULD PRODUCE
SOME LIGHT SHOWERS OR DRIZZLE AT ABOUT ANY TIME...BUT IT APPEARS
THAT THE NEXT ORGANIZED ROUND OF PRECIPITATION WILL HOLD OFF UNTIL
LATER THIS AFTERNOON AND MORE SO THIS EVENING AS ANOTHER SHORT
WAVE EJECTS AHEAD OF ADVANCING WEST COAST UPPER TROUGH.
THUNDERSTORMS CHANCES INCREASE MARKEDLY THIS EVENING AS THIS NEXT
WAVE APPROACHES THIS EVENING. SOME OF THESE ELEVATED STORMS
TONIGHT MAY ALSO HAVE THE CAPABILITY OF PRODUCING LARGE HAIL WITH
STEEP LAPSE RATES AND STRONG DEEP SHEAR.
SHOWERS AND THUNDERSTORMS WILL VERY LIKELY BE ONGOING ACROSS THE
FORECAST AREA EARLY THURSDAY MORNING...AND THE EFFECT OF THE
RESULTING COLD POOL AND CLOUDINESS WILL LIKELY COMPLICATE THE
EVOLUTION OF AFTERNOON POTENTIALLY SEVERE CONVECTION ACROSS THE
AREA. NONETHELESS...A STRONG AND VERY DYNAMIC SHORT WAVE WILL
EMANATE FROM THE CURRENT WEST COAST TROUGH RESULTING IN A
DEEPENING SURFACE LOW LIFTING NORTHEAST INTO FAR NORTHERN ILLINOIS
OR SOUTHERN WISCONSIN BY THURSDAY EVENING. THE COMBINATION OF THE
APPROACHING VIGOROUS SHORT WAVE AND DEEPENING SURFACE LOW WILL
LIFT THE CURRENT STATIONARY FRONT NORTHWARD ACROSS THE FORECAST
AREA AS A WARM FRONT...WITH THE WARM SECTOR SOUTH OF THE FRONT
EXPECTED TO BECOME MODERATELY UNSTABLE DURING THE AFTERNOON AS
MLCAPES INCREASE TO 1500-2500 J/KG. STRONG WEST-SOUTHWEST FLOW
ALOFT AND BACKED SOUTHERLY WINDS IN LOW LEVELS AHEAD OF THE LOW
WILL SUPPLY COPIOUS SHEAR... SUPPORTIVE OF ORGANIZED SEVERE
THUNDERSTORMS DEVELOPING DURING THE AFTERNOON AND EARLY EVENING
HOURS AHEAD OF THE COLD FRONT WHICH WILL PUSH ACROSS THE CWA BY
MIDNIGHT. SPC HAS MAINTAINED A LARGE ENHANCED SEVERE RISK ACROSS
THE AREA FOR DAY 2/THURSDAY...WITH SOME UNCERTAINTY REMAINING
PRIMARILY TO THE EFFECT OF MORNING CONVECTION ON MESOSCALE SURFACE
FEATURES BY THURSDAY AFTERNOON. IF THE DYNAMIC SYSTEM IS ABLE TO
OVERCOME STABILIZING INFLUENCE OF EARLIER STORMS...AND IT LIKELY
WILL TO SOME DEGREE...THEN A SIGNIFICANT RISK OF DAMAGING
WIND...LARGE HAIL AND TORNADOES WILL EXIST.
WITH THE SURFACE LOW PASSING NEAR/NORTH OF THE AREA THURSDAY
NIGHT...THE COLD FRONT WILL SWEEP EAST DURING THE EVENING AND
BRING AN END TO THE SEVERE THREAT AS DRIER/COOLER AIR SPREADS IN.
A STRONG NORTHERN STREAM SHORT WAVE IS PROGGED TO DIG ACROSS THE
UPPER MIDWEST BEHIND THE FIRST SYSTEM ON FRIDAY...THOUGH DRY
AIRMASS AND CAPPING INVERSION IN 700-600 MB LAYER NOTED IN
FORECAST SOUNDINGS SHOULD PRECLUDE PRECIP IN ANY ORGANIZED
FASHION.
TEMPS...SHARP CONTRAST CONTINUES TODAY-TONIGHT WITH EAST-
NORTHEAST FLOW NORTH OF THE STATIONARY FRONT AND MOIST/CLOUDY LOW
LEVEL AIR MASS. MAY VERY WELL SEE HIGHS TODAY RANGING FROM THE
MID-40S IN FAR NORTHEAST IL TO THE LOWER 70S ALONG THE LOT/ILX
BORDER. WITH FRONT LIFTING NORTH THURSDAY MUCH OF THE AREA MAY BE
IN THE 70S...THOUGH AGAIN MORNING CONVECTION AND RESIDUAL OUTFLOW
OR CLOUDS COULD AFFECT MAX TEMPS. COOLER BUT NEAR NORMAL FRIDAY
BEHIND THE COLD FRONT...BUT STILL 55-60.
RATZER
&&
.LONG TERM...
142 AM CDT
SATURDAY THROUGH TUESDAY...
THE FIRST FEW PERIODS OF THE EXTENDED LOOK TO BE RELATIVELY
BENIGN FOR THE GREAT LAKES REGION...WITH ENSEMBLES DEMONSTRATING
MINIMAL SPREAD IN THE 500MB WAVE PATTERN. WEAK TROUGHING WILL BE
PIVOTING EAST ACROSS THE MID-ATLANTIC REGION SAT...WITH DIFFLUENT
FLOW ARRIVING FOR THE WESTERN GREAT LAKES SAT. THE PATTERN QUICKLY
FLATTENS SUN...WITH PRECIP CHANCES RETURNING FOR THE SECOND HALF
OF THE WEEKEND INTO EARLY NEXT WEEK.
ENSEMBLES BEGIN TO POINT TOWARDS A TROUGH TRYING TO DIG INTO THE
WESTERN CONUS MON...WHICH COULD SUPPORT A SHORTWAVE DEVELOPING ALONG
THE LEE-SIDE OF THE ROCKIES. WITH THE WESTERN GULF OF MEXICO
OPEN...MOISTURE SHOULD EASILY LIFT NORTH TOWARDS THE OZARKS INTO IL
LATE MON INTO TUE. AS A RESULT INSTABILITY WILL LIKELY INCREASE...SO
WILL CONTINUE TO MENTION THUNDER MON/TUE OF NEXT WEEK.
WITH THE RELATIVELY ACTIVE FLOW...THE EXTENDED TEMPS MAY END UP
SLIGHTLY ABOVE SEASONAL OR MAINLY IN THE LOW/MID 60S. PRIOR TO THE
SHORTWAVE ARRIVAL MON...TEMPS MAY PUSH INTO THE UPR 60S OR NEAR 70.
OVERNIGHT LOWS WILL ALSO REMAIN MILD.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* IFR VSBY IMPROVES TO MVFR THIS AFTERNOON
* LIFR CIGS POTENTIALLY IMPROVING TO IFR THIS EVENING
* SCATTERED THUNDERSTORMS DEVELOPING THIS EVENING AND CONTINUING
OVERNIGHT
* LIFR VIS/CIGS POSSIBLE TONIGHT...IMPROVING THURSDAY MORNING.
JEE/IZZI
//DISCUSSION...UPDATED 12Z...
CIGS/VIS SHOULD SLOWLY IMPROVE THIS MORNING WITH IFR CIGS LIKELY
BY THIS AFTERNOON WITH VIS IMPROVING POSSIBLY TO MVFR. CIGS/VIS
COULD POSSIBLY LOWER BACK TO LIFR THIS EVENING INTO EARLY
OVERNIGHT BUT CONFIDENCE IS LOW.
COMPLEX OF THUNDERSTORMS ACROSS EASTERN IL INTO NORTH CENTRAL
INDIANA WILL CONTINUE TO MOVE EAST/SOUTHEAST AND AWAY FROM THE
AREA THIS MORNING. SOME DRIZZLE THIS MORNING AND PERHAPS A BRIEF
SHOWER BUT THE DAYLIGHT HOURS APPEAR DRY FOR THE TERMINALS. FOCUS
SHIFTS TO COMPLEX OF THUNDERSTORMS OVER NORTHEAST MO...WHICH WILL
LIKELY MOVE EAST/NORTHEAST AND INTO PARTS OF WEST CENTRAL IL MID/
LATE AFTERNOON. ADDITIONAL THUNDERSTORMS ARE EXPECTED TO DEVELOP
ACROSS NORTHERN IL THIS EVENING AND CONTINUE INTO THE OVERNIGHT
HOURS. CONFIDENCE REGARDING TIMING/LOCATION/COVERAGE IS STILL LOW
ENOUGH THAT OPTED TO CONTINUE WITH A LONGER DURATION OF VICINITY
THUNDER.
GENERALLY EASTERLY WINDS WILL CONTINUE THRU THIS EVENING WITH
SPEEDS LIKELY AT OR ABOVE 10 KTS. WINDS WILL BEGIN TO TURN
SOUTHEAST LATER THIS EVENING AND OVERNIGHT...THEN MORE SOUTH/
SOUTHWEST THURSDAY MORNING AS A WARM FRONT LIFTS THROUGH THE
TERMINALS. WHEN THIS OCCURS...EXPECT RAPID IMPROVEMENT THROUGH
MVFR CIGS AND LIKELY TO PREVAILING VFR CIGS...OUTSIDE PRECIP...
INTO THURSDAY MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM CONFIDENCE IN VERY SLOW IMPROVEMENT IN CIGS/VSBY THROUGH
THIS EVENING
* MEDIUM IN WINDS THROUGH THE PERIOD.
* MEDIUM CONFIDENCE IN TS TONIGHT...LOW FOR TIMING AND COVERAGE.
JEE/CMS/IZZI
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
* THURSDAY NIGHT...STRONG TSRA IN THE EVENING. MVFR POSSIBLE.
STRONG/GUSTY SOUTHWEST WINDS BECOMING WEST.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...SLIGHT CHANCE OF SHRA. SOUTH WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. SOUTHWEST WINDS.
* TUESDAY...CHANCE OF SHRA. SOUTHWEST WINDS.
&&
.MARINE...
415 AM...A FRONTAL BOUNDARY WILL REMAIN STATIONARY JUST SOUTH OF
LAKE MICHIGAN INTO THIS EVENING...THEN BEGIN TO LIFT NORTH ACROSS
THE LAKE LATE TONIGHT AND THURSDAY AS A WARM FRONT AS LOW PRESSURE
OVER THE PLAINS MOVES NORTHEAST TONIGHT AND THURSDAY...REACHING
NORTHERN LAKE MICHIGAN BY FRIDAY MORNING. NORTHEAST WINDS WILL
REMAIN IN THE 20-25KT RANGE TODAY...WITH SOME HIGHER GUSTS
POSSIBLE. WINDS WILL SLOWLY DIMINISH LATE TONIGHT INTO THURSDAY
MORNING...THEN AS WINDS SHIFTING SOUTHWESTERLY THURSDAY AFTERNOON
AND ESPECIALLY THURSDAY EVENING...THEY WILL INCREASE TO 30 KT...
SHIFTING WESTERLY THURSDAY NIGHT AFTER A COLD FRONT MOVES ACROSS
THE LAKE. WINDS WILL SLOWLY DIMINISH FRIDAY AFTERNOON INTO FRIDAY
EVENING...THEN BECOME LIGHT SATURDAY AS HIGH PRESSURE MOVES ACROSS
THE REGION. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 5 AM
THURSDAY.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1224 PM CDT Wed Apr 8 2015
.UPDATE...
ISSUED AT 1034 AM CDT WED APR 8 2015
Have made some adjustments to PoPs and Wx based on position of
boundaries from earlier convection and the anticipated evolution
of incoming wave. High temperature forecasts remain reasonable.
Elevated boundary over southeast forecast area continues to
produce isolated thunderstorms as it sags south. Next system is
moving through Missouri this morning. Leading edge is weakening as
it moves into more stable air in wake of morning convection and
fog. This trend should change as temps rise well into the 70s and
dew pts reach well into 60s over much of the southern two-thirds
of CWA. Lastest HRRR suggests that best chances for afternoon storms
should remain south of I-72.
&&
.SHORT TERM...(Today)
ISSUED AT 255 AM CDT WED APR 8 2015
Latest surface analysis indicates the frontal boundary that was
holding stationary over south central Illinois has shifted further
north early this morning as a weak wave of low pressure was
approaching west central Illinois. Scattered convection has been
occurring north of the boundary over parts of east central Iowa
east into our far northern counties with some nickel hail reported
over the past hour around Lacon in Marshall county. We expect the
scattered convection to continue into the morning hours as the wave
rides east along the boundary. As the surface low shifts to our east
later this morning, there may actually be a southward push to the
front which is going to cause some significant problems with respect
to the afternoon temperatures, especially along and north of I-74.
The latest HRRR does indicate another weak wave forming to our west
along the boundary early this afternoon with another complex of
storms approaching west central IL. Not sure if this particular
complex of storms will ride along the boundary into central Illinois
or dive more southeast into the higher instability air mass south
of the front. POPs will increase again this afternoon in response to
this secondary wave approaching from the west. Severe potential
increases this afternoon thru this evening as the boundary gets
a push northward as the more significant shortwave pushes into the
Plains. With the warm front expected to edge across the area this
afternoon and evening, damaging wind gusts, large hail and isolated
tornadoes will all be possible. The tornado threat looks tied more
into areas along and just north of the warm front later this
afternoon and evening. Coolest temps north of I-74 where more of an
easterly flow will prevail, while south of the boundary, a blend of
the MET/MAV guid seems reasonable at this point.
&&
.LONG TERM...(Tonight through Tuesday)
ISSUED AT 255 AM CDT WED APR 8 2015
Severe weather threat through Thursday evening continues to dominate
the first part of the forecast. Current upper low moving into
northwest Nevada will open up but remain a fairly sharp wave as it
traverses the Plains on Thursday. This will help develop a surface
low over western Kansas this evening, which will surge northeast and
shove the frontal boundary back northward tonight. The trailing cold
front will sweep from west to east across the state Thursday evening
as a result.
Convection to our southwest expected to expand northeastward into
the mid-Mississippi Valley this evening. Latest SPC Day1 outlook
extended the slight risk across the entire CWA, with an enhanced
risk of severe storms from basically Springfield-Peoria westward.
This enhanced risk covers the entire area on Thursday, with
high-resolution models focusing on the mid-afternoon through early
evening time frame as the best potential in our area.
Short period of cooler and drier weather on tap for the first part
of the weekend, as high pressure drifts across the Midwest. However,
longer range models showing extended periods of rain chances early
next week. The GFS and ECMWF have a sizable range on the position
of a frontal boundary that will be setting up Sunday night and
Monday, both starting off roughly along I-70 but the GFS shows a
much stronger surge to the north by Tuesday. However, with both
favoring some sort of precip, have kept healthy rain chances in the
forecast for early next week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 1223 PM CDT WED APR 8 2015
Next cluster of storms moving into western Illinois at this time.
As they do so they will be encountering more unstable conditions
once they move east of the Illinois river and into the warm
sector. Some of the convection may become significant with
convective wind shear. Another convective cluster is expected
overnight however there is more uncertianty on the track of the
overnight system as it may impact areas south of the central
Illinois terminals. Will mainly reflect this uncertainty by
including a VCTS rather than a dominant group. Winds will also be
quite uncertian as the frontal boundary in the area will be
modulated by the track of the clusters. Abundant boundary layer
moisture both near and north of the front will keep CIGS in place
with IFR to at best MVFR conditions.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barker
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Barker
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1115 AM CDT WED APR 8 2015
.SHORT TERM...
347 AM CDT
THROUGH THURSDAY...
TODAY THROUGH FRIDAY NIGHT...
MAIN FOCUS IS ON PERIODS OF CONVECTION...PARTICULARLY THIS
MORNING ACROSS PART OF THE FORECAST AREAS...AND ACROSS THE ENTIRE
AREA TONIGHT INTO THURSDAY. SEVERE WEATHER THREAT REMAINS OF GREAT
CONCERN THURSDAY AFTERNOON AND EVENING.
EARLY MORNING SURFACE ANALYSIS DEPICTS LOW PRESSURE OVER
NORTHEASTERN MISSOURI...WITH AN INVERTED TROUGH EXTENDING
NORTHEAST ACROSS SOUTHEAST WI/LAKE MICHIGAN. THESE FEATURES APPEAR
TO BE ASSOCIATED WITH A COUPLE OF MID-LEVEL SHORT WAVE TROUGHS
PROPAGATING ACROSS THE REGION IN BROAD WEST-SOUTHWESTERLY FLOW
ALOFT. A CLUSTER OF THUNDERSTORMS HAD DEVELOPED ACROSS SOUTHEAST
IOWA LAST EVENING IN LOW LEVEL WARM/MOIST ADVECTION MAXIMA
NORTHEAST OF THE SURFACE LOW...AND CONTINUE TO PERSIST AND EXPAND
SLOWLY EASTWARD ACROSS PARTS OF ILLINOIS EARLY THIS MORNING ON 30
KT 925 MB JET AHEAD OF SHORT WAVE. THESE STORMS ARE LIKELY TO
CONTINUE TO DEVELOP EASTWARD ACROSS MAINLY THE SOUTHERN TWO THIRDS
OR SO OF THE CWA EARLY THIS MORNING AS THE SURFACE WAVE MOVE
THROUGH THE AREA. SPC MESOANALYSIS DATA INDICATES UPSTREAM AIR
MASS CHARACTERIZED BY STEEP MID-LEVEL LAPSE RATES IN EXCESS OF 7.5
C/KM YIELDING 1000-1500 J/KG OF ELEVATED MUCAPE...AND ROUGHLY
40-45 KT OF EFFECTIVE DEEP LAYER BULK SHEAR. SOME OF THE STRONGER
CORES MAY BE CAPABLE OF PRODUCING SOME MARGINAL HAIL THIS
MORNING...THOUGH AN OVERALL WEAKENING TREND IS EXPECTED AS THE LOW
LEVEL FLOW VEERS MORE WESTERLY AND DECREASES AND REDUCES LOW LEVEL
MOISTURE TRANSPORT/THETA-E ADVECTION ACROSS OUR SOUTH AND
SOUTHEAST COUNTIES. THIS TREND IS SUPPORTED BY HIGH-RES HRRR/RAP
GUIDANCE WHICH INDICATE ACTIVITY MOVING ACROSS THE AREA THROUGH
13-14Z.
MOIST/SATURATED LOW LEVEL AIR MASS HAS ALSO REDUCED VISIBILITY IN
FOG OVER THE PAST SEVERAL HOURS...WITH SOME PATCHES OF DENSE FOG
NOTED. MAY HAVE TO CONSIDER A HEADLINE...THOUGH MORNING SHOWERS
MAY HELP RAISE VISIBILITY SOMEWHAT AND WILL CONTINUE TO MONITOR.
NOT MUCH IS EXPECTED IN THE WAY OF ORGANIZED PRECIP FROM MID-
MORNING INTO THIS AFTERNOON...WITH PASSAGE OF THE SHORT WAVE AND
WEAKENING OF THE SURFACE WAVE ALONG THE FRONT TO OUR SOUTH. WEAK
BUT PERSISTENT SOUTHWEST FLOW WILL CONTINUE ABOVE THE SHALLOW COOL
BOUNDARY LAYER NORTH OF THE SURFACE FRONT...WHICH COULD PRODUCE
SOME LIGHT SHOWERS OR DRIZZLE AT ABOUT ANY TIME...BUT IT APPEARS
THAT THE NEXT ORGANIZED ROUND OF PRECIPITATION WILL HOLD OFF UNTIL
LATER THIS AFTERNOON AND MORE SO THIS EVENING AS ANOTHER SHORT
WAVE EJECTS AHEAD OF ADVANCING WEST COAST UPPER TROUGH.
THUNDERSTORMS CHANCES INCREASE MARKEDLY THIS EVENING AS THIS NEXT
WAVE APPROACHES THIS EVENING. SOME OF THESE ELEVATED STORMS
TONIGHT MAY ALSO HAVE THE CAPABILITY OF PRODUCING LARGE HAIL WITH
STEEP LAPSE RATES AND STRONG DEEP SHEAR.
SHOWERS AND THUNDERSTORMS WILL VERY LIKELY BE ONGOING ACROSS THE
FORECAST AREA EARLY THURSDAY MORNING...AND THE EFFECT OF THE
RESULTING COLD POOL AND CLOUDINESS WILL LIKELY COMPLICATE THE
EVOLUTION OF AFTERNOON POTENTIALLY SEVERE CONVECTION ACROSS THE
AREA. NONETHELESS...A STRONG AND VERY DYNAMIC SHORT WAVE WILL
EMANATE FROM THE CURRENT WEST COAST TROUGH RESULTING IN A
DEEPENING SURFACE LOW LIFTING NORTHEAST INTO FAR NORTHERN ILLINOIS
OR SOUTHERN WISCONSIN BY THURSDAY EVENING. THE COMBINATION OF THE
APPROACHING VIGOROUS SHORT WAVE AND DEEPENING SURFACE LOW WILL
LIFT THE CURRENT STATIONARY FRONT NORTHWARD ACROSS THE FORECAST
AREA AS A WARM FRONT...WITH THE WARM SECTOR SOUTH OF THE FRONT
EXPECTED TO BECOME MODERATELY UNSTABLE DURING THE AFTERNOON AS
MLCAPES INCREASE TO 1500-2500 J/KG. STRONG WEST-SOUTHWEST FLOW
ALOFT AND BACKED SOUTHERLY WINDS IN LOW LEVELS AHEAD OF THE LOW
WILL SUPPLY COPIOUS SHEAR... SUPPORTIVE OF ORGANIZED SEVERE
THUNDERSTORMS DEVELOPING DURING THE AFTERNOON AND EARLY EVENING
HOURS AHEAD OF THE COLD FRONT WHICH WILL PUSH ACROSS THE CWA BY
MIDNIGHT. SPC HAS MAINTAINED A LARGE ENHANCED SEVERE RISK ACROSS
THE AREA FOR DAY 2/THURSDAY...WITH SOME UNCERTAINTY REMAINING
PRIMARILY TO THE EFFECT OF MORNING CONVECTION ON MESOSCALE SURFACE
FEATURES BY THURSDAY AFTERNOON. IF THE DYNAMIC SYSTEM IS ABLE TO
OVERCOME STABILIZING INFLUENCE OF EARLIER STORMS...AND IT LIKELY
WILL TO SOME DEGREE...THEN A SIGNIFICANT RISK OF DAMAGING
WIND...LARGE HAIL AND TORNADOES WILL EXIST.
WITH THE SURFACE LOW PASSING NEAR/NORTH OF THE AREA THURSDAY
NIGHT...THE COLD FRONT WILL SWEEP EAST DURING THE EVENING AND
BRING AN END TO THE SEVERE THREAT AS DRIER/COOLER AIR SPREADS IN.
A STRONG NORTHERN STREAM SHORT WAVE IS PROGGED TO DIG ACROSS THE
UPPER MIDWEST BEHIND THE FIRST SYSTEM ON FRIDAY...THOUGH DRY
AIRMASS AND CAPPING INVERSION IN 700-600 MB LAYER NOTED IN
FORECAST SOUNDINGS SHOULD PRECLUDE PRECIP IN ANY ORGANIZED
FASHION.
TEMPS...SHARP CONTRAST CONTINUES TODAY-TONIGHT WITH EAST-
NORTHEAST FLOW NORTH OF THE STATIONARY FRONT AND MOIST/CLOUDY LOW
LEVEL AIR MASS. MAY VERY WELL SEE HIGHS TODAY RANGING FROM THE
MID-40S IN FAR NORTHEAST IL TO THE LOWER 70S ALONG THE LOT/ILX
BORDER. WITH FRONT LIFTING NORTH THURSDAY MUCH OF THE AREA MAY BE
IN THE 70S...THOUGH AGAIN MORNING CONVECTION AND RESIDUAL OUTFLOW
OR CLOUDS COULD AFFECT MAX TEMPS. COOLER BUT NEAR NORMAL FRIDAY
BEHIND THE COLD FRONT...BUT STILL 55-60.
RATZER
&&
.LONG TERM...
142 AM CDT
SATURDAY THROUGH TUESDAY...
THE FIRST FEW PERIODS OF THE EXTENDED LOOK TO BE RELATIVELY
BENIGN FOR THE GREAT LAKES REGION...WITH ENSEMBLES DEMONSTRATING
MINIMAL SPREAD IN THE 500MB WAVE PATTERN. WEAK TROUGHING WILL BE
PIVOTING EAST ACROSS THE MID-ATLANTIC REGION SAT...WITH DIFFLUENT
FLOW ARRIVING FOR THE WESTERN GREAT LAKES SAT. THE PATTERN QUICKLY
FLATTENS SUN...WITH PRECIP CHANCES RETURNING FOR THE SECOND HALF
OF THE WEEKEND INTO EARLY NEXT WEEK.
ENSEMBLES BEGIN TO POINT TOWARDS A TROUGH TRYING TO DIG INTO THE
WESTERN CONUS MON...WHICH COULD SUPPORT A SHORTWAVE DEVELOPING ALONG
THE LEE-SIDE OF THE ROCKIES. WITH THE WESTERN GULF OF MEXICO
OPEN...MOISTURE SHOULD EASILY LIFT NORTH TOWARDS THE OZARKS INTO IL
LATE MON INTO TUE. AS A RESULT INSTABILITY WILL LIKELY INCREASE...SO
WILL CONTINUE TO MENTION THUNDER MON/TUE OF NEXT WEEK.
WITH THE RELATIVELY ACTIVE FLOW...THE EXTENDED TEMPS MAY END UP
SLIGHTLY ABOVE SEASONAL OR MAINLY IN THE LOW/MID 60S. PRIOR TO THE
SHORTWAVE ARRIVAL MON...TEMPS MAY PUSH INTO THE UPR 60S OR NEAR 70.
OVERNIGHT LOWS WILL ALSO REMAIN MILD.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* IFR VSBY IN FOG IMPROVES TO MVFR DURING THE AFTERNOON
* LIFR CIGS POTENTIALLY IMPROVING TO IFR DURING THIS AFTERNOON OR
EVENING
* SCATTERED THUNDERSTORMS DEVELOPING LATE THIS EVENING AND
OVERNIGHT
* LIFR VIS/CIGS POSSIBLE TONIGHT...IMPROVING THURSDAY MORNING.
JEE/IZZI
//DISCUSSION...UPDATED 12Z...
CIGS/VIS SHOULD SLOWLY IMPROVE THIS MORNING WITH IFR CIGS LIKELY
BY THIS AFTERNOON WITH VIS IMPROVING POSSIBLY TO MVFR. CIGS/VIS
COULD POSSIBLY LOWER BACK TO LIFR THIS EVENING INTO EARLY
OVERNIGHT BUT CONFIDENCE IS LOW.
COMPLEX OF THUNDERSTORMS ACROSS EASTERN IL INTO NORTH CENTRAL
INDIANA WILL CONTINUE TO MOVE EAST/SOUTHEAST AND AWAY FROM THE
AREA THIS MORNING. SOME DRIZZLE THIS MORNING AND PERHAPS A BRIEF
SHOWER BUT THE DAYLIGHT HOURS APPEAR DRY FOR THE TERMINALS. FOCUS
SHIFTS TO COMPLEX OF THUNDERSTORMS OVER NORTHEAST MO...WHICH WILL
LIKELY MOVE EAST/NORTHEAST AND INTO PARTS OF WEST CENTRAL IL MID/
LATE AFTERNOON. ADDITIONAL THUNDERSTORMS ARE EXPECTED TO DEVELOP
ACROSS NORTHERN IL THIS EVENING AND CONTINUE INTO THE OVERNIGHT
HOURS. CONFIDENCE REGARDING TIMING/LOCATION/COVERAGE IS STILL LOW
ENOUGH THAT OPTED TO CONTINUE WITH A LONGER DURATION OF VICINITY
THUNDER.
GENERALLY EASTERLY WINDS WILL CONTINUE THRU THIS EVENING WITH
SPEEDS LIKELY AT OR ABOVE 10 KTS. WINDS WILL BEGIN TO TURN
SOUTHEAST LATER THIS EVENING AND OVERNIGHT...THEN MORE SOUTH/
SOUTHWEST THURSDAY MORNING AS A WARM FRONT LIFTS THROUGH THE
TERMINALS. WHEN THIS OCCURS...EXPECT RAPID IMPROVEMENT THROUGH
MVFR CIGS AND LIKELY TO PREVAILING VFR CIGS...OUTSIDE PRECIP...
INTO THURSDAY MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM CONFIDENCE IN SLOW IMPROVMENT IN CIGS/VSBY REST OF TODAY
* MEDIUM TO HIGH IN WINDS THROUGH TONIGHT...MEDIUM TO LOW WITH WINDS
ON THURSDAY MORNING WITH TIMING OF WARM FRONT.
* MEDIUM CONFIDENCE IN TS OVERNIGHT...LOW FOR TIMING AND COVERAGE.
JEE/CMS/IZZI/KMH/EJL
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
* THURSDAY NIGHT...STRONG TSRA IN THE EVENING. MVFR POSSIBLE.
STRONG/GUSTY SOUTHWEST WINDS BECOMING WEST.
* FRIDAY...DRY/VFR. STRONG/GUSTY WEST WINDS.
* SATURDAY...DRY/VFR. SOUTH WINDS. LAKE BREEZE POSSIBLE.
* SUNDAY...SLIGHT CHANCE OF SHRA. SOUTH WINDS.
* MONDAY...CHANCE OF SHRA/TSRA. SOUTHWEST WINDS.
* TUESDAY...CHANCE OF SHRA. SOUTHWEST WINDS.
&&
.MARINE...
415 AM...A FRONTAL BOUNDARY WILL REMAIN STATIONARY JUST SOUTH OF
LAKE MICHIGAN INTO THIS EVENING...THEN BEGIN TO LIFT NORTH ACROSS
THE LAKE LATE TONIGHT AND THURSDAY AS A WARM FRONT AS LOW PRESSURE
OVER THE PLAINS MOVES NORTHEAST TONIGHT AND THURSDAY...REACHING
NORTHERN LAKE MICHIGAN BY FRIDAY MORNING. NORTHEAST WINDS WILL
REMAIN IN THE 20-25KT RANGE TODAY...WITH SOME HIGHER GUSTS
POSSIBLE. WINDS WILL SLOWLY DIMINISH LATE TONIGHT INTO THURSDAY
MORNING...THEN AS WINDS SHIFTING SOUTHWESTERLY THURSDAY AFTERNOON
AND ESPECIALLY THURSDAY EVENING...THEY WILL INCREASE TO 30 KT...
SHIFTING WESTERLY THURSDAY NIGHT AFTER A COLD FRONT MOVES ACROSS
THE LAKE. WINDS WILL SLOWLY DIMINISH FRIDAY AFTERNOON INTO FRIDAY
EVENING...THEN BECOME LIGHT SATURDAY AS HIGH PRESSURE MOVES ACROSS
THE REGION. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 5 AM
THURSDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1034 AM CDT Wed Apr 8 2015
.UPDATE...
ISSUED AT 1034 AM CDT WED APR 8 2015
Have made some adjustments to PoPs and Wx based on position of
boundaries from earlier convection and the anticipated evolution
of incoming wave. High temperature forecasts remain reasonable.
Elevated boundary over southeast forecast area continues to
produce isolated thunderstorms as it sags south. Next system is
moving through Missouri this morning. Leading edge is weakening as
it moves into more stable air in wake of morning convection and
fog. This trend should change as temps rise well into the 70s and
dew pts reach well into 60s over much of the southern two-thirds
of CWA. Lastest HRRR suggests that best chances for afternoon storms
should remain south of I-72.
&&
.SHORT TERM...(Today)
ISSUED AT 255 AM CDT WED APR 8 2015
Latest surface analysis indicates the frontal boundary that was
holding stationary over south central Illinois has shifted further
north early this morning as a weak wave of low pressure was
approaching west central Illinois. Scattered convection has been
occurring north of the boundary over parts of east central Iowa
east into our far northern counties with some nickel hail reported
over the past hour around Lacon in Marshall county. We expect the
scattered convection to continue into the morning hours as the wave
rides east along the boundary. As the surface low shifts to our east
later this morning, there may actually be a southward push to the
front which is going to cause some significant problems with respect
to the afternoon temperatures, especially along and north of I-74.
The latest HRRR does indicate another weak wave forming to our west
along the boundary early this afternoon with another complex of
storms approaching west central IL. Not sure if this particular
complex of storms will ride along the boundary into central Illinois
or dive more southeast into the higher instability air mass south
of the front. POPs will increase again this afternoon in response to
this secondary wave approaching from the west. Severe potential
increases this afternoon thru this evening as the boundary gets
a push northward as the more significant shortwave pushes into the
Plains. With the warm front expected to edge across the area this
afternoon and evening, damaging wind gusts, large hail and isolated
tornadoes will all be possible. The tornado threat looks tied more
into areas along and just north of the warm front later this
afternoon and evening. Coolest temps north of I-74 where more of an
easterly flow will prevail, while south of the boundary, a blend of
the MET/MAV guid seems reasonable at this point.
&&
.LONG TERM...(Tonight through Tuesday)
ISSUED AT 255 AM CDT WED APR 8 2015
Severe weather threat through Thursday evening continues to dominate
the first part of the forecast. Current upper low moving into
northwest Nevada will open up but remain a fairly sharp wave as it
traverses the Plains on Thursday. This will help develop a surface
low over western Kansas this evening, which will surge northeast and
shove the frontal boundary back northward tonight. The trailing cold
front will sweep from west to east across the state Thursday evening
as a result.
Convection to our southwest expected to expand northeastward into
the mid-Mississippi Valley this evening. Latest SPC Day1 outlook
extended the slight risk across the entire CWA, with an enhanced
risk of severe storms from basically Springfield-Peoria westward.
This enhanced risk covers the entire area on Thursday, with
high-resolution models focusing on the mid-afternoon through early
evening time frame as the best potential in our area.
Short period of cooler and drier weather on tap for the first part
of the weekend, as high pressure drifts across the Midwest. However,
longer range models showing extended periods of rain chances early
next week. The GFS and ECMWF have a sizable range on the position
of a frontal boundary that will be setting up Sunday night and
Monday, both starting off roughly along I-70 but the GFS shows a
much stronger surge to the north by Tuesday. However, with both
favoring some sort of precip, have kept healthy rain chances in the
forecast for early next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
ISSUED AT 615 AM CDT WED APR 8 2015
Frontal boundary located over the northern portion of the forecast
area this morning will be the focus for periods of showers and
thunderstorms along with LIFR cigs and vsbys with some of the
heavy thunderstorms. Outside of the convection, and south of
the frontal boundary, we will see a period of VFR cigs today
with the main band of convection moving in after 21z but scattered
in nature, so will continue to handle with VCTS until we see how
the storms develop to our west later today.
Surface winds will be quite variable in direction and speed in
and near the thunderstorms today. Most of our area will see
southeast winds at 10 to 15 kts today into tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barker
SHORT TERM...Smith
LONG TERM...Geelhart
AVIATION...Smith
AREA FORECAST DISCUSSION...CORRECTED
NWS NORTHERN INDIANA
400 PM EDT WED APR 8 2015
.SYNOPSIS...
ISSUED AT 1003 AM EDT WED APR 8 2015
SEVERAL PERIODS OF RAIN WILL BE POSSIBLE DURING THE NEXT COUPLE
OF DAYS. A STATIONARY FRONT OVER CENTRAL PORTIONS OF INDIANA AND
OHIO IS EXPECTED TO LIFT SLOWLY NORTH INTO MICHIGAN TONIGHT.
SCATTERED THUNDERSTORMS ARE POSSIBLE NEAR THE FRONT TODAY WITH
SHOWERS AND THUNDERSTORMS LIKELY BECOMING NUMEROUS TONIGHT. A COLD
FRONT WILL APPROACH THE AREA ON THURSDAY LIKELY CAUSING ANOTHER
ROUND OF THUNDERSTORMS. HIGHS TODAY ARE EXPECTED TO RANGE FROM
THE MID 50S NORTH OF THE FRONT IN SOUTHERN MICHIGAN TO THE LOW 70S
SOUTH OF THE FRONT SOUTH OF US 30. LOWS TONIGHT WILL BE IN THE
50S.
&&
.SHORT TERM...(THIS EVENING AND TONIGHT)
ISSUED AT 400 PM EDT WED APR 8 2015
BRIEF LULL IN PRECIP AND INCREASED LOW LEVEL MIXING IS CURRENTLY IN
PLACE ACROSS NORTHERN INDIANA THANKS TO MIDLEVEL SHORTWAVE
RIDGING/AVA IN THE WAKE OF THIS MORNING`S CONVECTION. MCS THAT MOVED
THROUGH CENTRAL INDIANA EARLIER TODAY SEEMS TO HAVE LEFT MOST OF OUR
AREA FAIRLY STABLE/CAPPED PER LATEST SPC/RAP MESOANALYSIS. FORECAST
SOUNDINGS SHOW A DECENT INVERSION AROUND 800MB...EVEN IN AREAS THAT
HAVE MANAGED TO MIX OUT. NAM12 TRIES TO WEAKEN THIS CAPPING
INVERSION IN OUR AREA LATER THIS AFTERNOON BUT RAP AND GFS KEEP IT
IN PLACE FOR MUCH OF THE EVENING...AT LEAST OUTSIDE OF THE FAR
SOUTH. BASED ON THE LATEST RADAR...SATELLITE...AND SURFACE
OBSERVATIONAL TRENDS...PREFER TO LEAN TOWARD THE RAP IDEA OF
KEEPING OUR CWA MAINLY CAPPED WITH CONVECTION TIED TO BETTER
INSTABILITY JUST TO OUR SOUTH. SYNOPTIC FORCING IS PRETTY MUDDLED
AT THIS POINT BUT THERE ARE SOME HINTS OF MODEST 300K ISENTROPIC
ASCENT JUST TO OUR SOUTH AS WELL. SPC HAS ISSUED A SEVERE
THUNDERSTORM WATCH UP TO OUR SOUTHWEST BORDER AND THIS SEEMS
REASONABLE. CURRENTLY WATCHING A CLUSTER OF STORMS OVER EASTERN
ILLINOIS THAT COULD SCRAPE OUR FAR SOUTHERN COUNTIES. IF THIS
ACTIVITY DOES CLIP OUR AREA...IT COULD VERY WELL PRODUCE SEVERE
WEATHER GIVEN DEEP LAYER SHEAR OVER 40 KTS AND MLCAPE VALUES OVER
2000 J/KG DUE TO MIDLEVEL LAPSE RATES AROUND 8 C/KM.
BETTER CHANCES FOR MORE WIDESPREAD RAIN AND THUNDERSTORMS EXPECTED
LATE OVERNIGHT. ANOTHER WEAK/EMBEDDED SHORTWAVE WILL EJECT NORTHEAST
ALONG WITH NOCTURNAL STRENGTHENING OF THE LOW LEVEL JET. ANOTHER
ROUND OF INCREASED MOISTURE FLUX CONVERGENCE AND ISENTROPIC ASCENT
IN A REGION OF MODERATE ELEVATED INSTABILITY MAY SUPPORT EXPANDING
CONVECTION LATE TONIGHT. EXACT TIMING AND LOCATION IS DIFFICULT TO
PINPOINT AT THIS STAGE WITH A VARIETY OF SOLUTIONS BEING OFFERED BY
LATEST HI-RES GUIDANCE. AM A LITTLE UNEASY WITH INHERITED
CATEGORICAL POPS GIVEN DRY SOLUTIONS BEING OFFERED BY SOME HI-RES
GUIDANCE SUCH AS THE 4KM SPC WRF-NMM. LOWERED POPS EARLIER IN THE
PERIOD BUT DID KEEP SOME CATEGORICAL POPS IN THE 09-12Z PERIOD OUT
OF RESPECT FOR THE INCREASING WARM/MOIST AIR ADVECTION AND MODEL
DEPICTIONS OF WEAK CVA FORCING.
OTHER ASPECT THAT DEMANDS SOME ATTENTION IS THE POTENTIAL FOR HEAVY
RAIN/FLOODING WITH MULTIPLE ROUNDS OF CONVECTION THIS WEEK. PW
VALUES DO SURGE TO AROUND 1.5 INCHES LATE TONIGHT (AND INTO
TOMORROW) AND HEAVY RAIN WILL CERTAINLY BE POSSIBLE WHEN/WHERE
CONVECTION DOES OCCUR. HOWEVER...POTENTIAL FOR TRAINING AND
BACKBUILDING CONVECTION IS LOW IN OUR AREA WITH RELATIVELY HIGH MBE
VELOCITIES AND THE FACT THAT STORM MOTION BECOMES A LITTLE MORE
ORTHOGONAL TO THE FRONT BY TOMORROW. OUTSIDE OF OUR FAR SOUTHEAST
COUNTIES...MOST OF THE CWA HAS ALSO NOT RECEIVED A LARGE AMOUNT OF
RAIN RECENTLY. THE THREAT FOR HEAVY RAIN AND LOCALIZED FLOODING DOES
EXIST BUT CONFIDENCE IS NOT HIGH ENOUGH FOR ANY TYPE OF WATCH
HEADLINE AT THIS POINT. AGAIN THE HIGHEST THREAT WILL BE IN OUR FAR
SOUTHEAST COUNTIES.
&&
.LONG TERM...(THURSDAY THROUGH WEDNESDAY)
ISSUED AT 400 PM EDT WED APR 8 2015
PRIMARY CONCERN WILL BE SEVERE WEATHER CHANCES TONIGHT INTO THURSDAY
NIGHT.
ALOFT...A DEEP 500MB TROUGH IN THE WESTERN CONUS WILL GRADUALLY
SHIFT EASTWARD INTO THE MIDWEST...TAKING ON A NEGATIVE TILT OVER
IA/IL AS IT ATTEMPTS TO BREAK DOWN THE RIDGE FIRMLY ANCHORED OVER
THE EAST COAST THURSDAY NIGHT. MODELS CLOSE THE LOW THU EVE BEFORE
LIFTING IT INTO SOUTHERN ONTARIO BY FRIDAY AFTERNOON.
AHEAD OF THE DEEPENING TROUGH...SFC LOW PRESSURE WILL DEVELOP OVER
THE CENTRAL PLAINS THIS EVENING AND TRAVEL NORTHEASTWARD INTO
SOUTHWESTERN IOWA BY 12Z THU. AS THE UPPER TROUGH/LOW APPROACHES
THE LLJ WILL STRENGTHEN...INTENSIFYING THE WARM AIR/MOISTURE
ADVECTION OVER THE CWA OVERNIGHT AND THURSDAY.
AS A RESULT...THE CWA WILL BE IN THE WARM SECTOR FROM LATE TONIGHT
INTO THURSDAY NIGHT. THIS WILL BRING CHANCES FOR SEVERE WEATHER.
MOISTURE IS PLENTIFUL...WITH PWATS INCREASING TO NEAR 1.4 INCHES
EARLY THU AFTERNOON. INSTABILITY IS DECENT...WITH LI VALUES RANGING
FROM -5 TO -2/SFC BASED CAPE AS HIGH AS 1500 J/KG BY LATE AFTERNOON.
0-6KM SHEAR IS SOMEWHAT PALTRY AT FIRST...AROUND 20-30 KNOTS...BUT
PICKS UP TO AROUND 40-50 KNOTS TOWARDS THE LATE AFTERNOON AS THE
UPPER LEVEL TROUGH APPROACHES. SHOWER/T-STORM ACTIVITY FROM THE
OVERNIGHT PERIOD WILL LIKELY CONTINUE THROUGH THE MORNING
HOURS...WITH MODELS SUPPORTING SHOWER/T-STORM DEVELOPMENT ALONG THE
STATIONARY/WARM FRONT THAT LIFTS NORTHWARD WITH THE BOUNDARY THROUGH
THE MORNING. SEVERE POTENTIAL EARLIER IN THE DAY WILL BE
LIMITED...WITH MORE MARGINAL INSTABILITY AND WEAK MID LEVEL LAPSE
RATES. WITH ABUNDANT MOISTURE...AND WITH ANY THUNDERSTORMS...HEAVY
RAIN IS A THREAT. FLOODING IS POSSIBLE IN AREAS THAT SEE HEAVY
RAINFALL FROM SEVERAL ROUNDS OF STORMS TONIGHT INTO FRIDAY.
THE STRONGEST STORMS ARE FORECAST TO INTIATE WITH THE COLD FRONT
OVER THE IL AREA BY THU AFTERNOON...WHERE FRONT TIMING IS MORE
FAVORABLE FOR SEVERE WX...DURING PEAK DAYTIME HEATING. EXPECT THESE
STORMS TO CROSS INTO OUR WESTERN CWA WITH THE FRONT BY THURSDAY
EVENING AND CONTINUE GENERALLY EASTWARD OVERNIGHT. THINKING THE
00-05Z TIME PERIOD IN THE WEST AND CENTRAL WILL BE THE BEST SHOT FOR
SEVERE WEATHER...WHEN ALL SVR T-STORM INGREDIENTS COME TOGETHER FOR
A BRIEF TIME. PRIMARY THREAT WOULD BE LARGE HAIL AND DAMAGING
WINDS...BUT CANNOT RULE OUT THE POSSIBILITY OF TORNADOES GIVEN 0-1
KM SHEAR GREATER THAN 30 KNOTS FROM 00-05Z. THINKING THAT THE
BIGGEST LIMITATION WITH THIS OVERALL SCENARIO IS
INSTABILITY...MODELS TEND TO OVERDO IT IN GENERAL. THIS IS
ESPECIALLY TRUE GIVEN THE UNCERTAINTY WITH THE MORNING
CONVECTION...AND THE LATE TIMING OF THE COLD FRONT/MAJOR FORCING.
TOOK A LOOK AT THE SHERB PARAMETER WHICH HAS SHOWN SOME SKILL IN
EVALUATING HSLC ENVIRONMENTS FOR SEVERE POTENTIAL...AND VALUES WERE
OVER 1-WHICH SUGGESTS A MORE SIGNIFICANT EVENT IS POSSIBLE.
AFTER 03Z HOWEVER...INSTABILITY REALLY BEGINS TO WANE...AND DRIER
AIR BEHIND THE FRONT QUICKLY INFILTRATES THE AREA. WOULD EXPECT ALL
MEASURABLE PRECIP TO EXIT THE CWA BY 15Z FRI AS HIGH PRESSURE STARTS
TO BUILD INTO THE AREA.
A SECONDARY SHORTWAVE ROTATING AROUND THE UPPER LOW OVER SOUTHERN
ONTARIO WILL DIVE SOUTHWARD FROM WI. MODELS SUGGEST PRECIPITATION
CHANCES ASSOCIATED WITH THIS ACROSS SOUTHWESTERN/SOUTHERN LOWER
MI...BUT THESE WILL BE LIMITED AT BEST. WINDS SHOULD GET GUSTY
FRIDAY THOUGH...WITH A DECENT PRESSURE RISE/FALL COUPLET CROSSING
THE CWA FRIDAY INTO FRI NIGHT.
ALL GOES QUIET AGAIN WITH HIGH PRESSURE OVERHEAD...UNTIL SUNDAY
NIGHT. AN UPPER LEVEL TROUGH/ASSOCIATED SURFACE LOW WILL MOVE FROM
NORTHERN ONTARIO/UPPER MI/NORTHERN WI SUNDAY NIGHT AND CONTINUE INTO
HUDSON BAY BY MONDAY AFTERNOON. THIS WILL BRING A COLD FRONT AND
ADDITIONAL CHANCES FOR SHOWERS/T-STORMS DURING THIS TIME FRAME.
AROUND THE SAME TIME...ANOTHER LOW DEVELOPS OVER THE CENTRAL PLAINS
AND BEGINS TO LIFT NORTHWARD...WEAKENING AS IT LIFTS TOWARDS THE
OHIO VALLEY TUE AND WED. THIS WILL ALLOW PRECIPITATION TO CONTINUE
THROUGH MUCH OF NEXT WEEK. TEMPS WILL BE NEAR NORMAL FOR THIS TIME
FRAME...MAINLY IN THE 60S AND LOW 70S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 200 PM EDT WED APR 8 2015
SHORTWAVE RIDGING IN THE WAKE OF MORNING CONVECTION IS CURRENTLY
PROVIDING A BREAK IN PRECIP ALONG WITH AN AREA OF VFR CONDITIONS
ACROSS NORTHERN INDIANA. PRECIP AND LOW LEVEL MOISTURE WILL RETURN
TONIGHT AS ANOTHER SHORTWAVE TROUGH MOVES OVER THE AREA AND THE
LLJ RAMPS UP. CONFIDENCE IN TIMING AND COVERAGE OF THUNDERSTORMS
IS LOW AT THIS POINT AND WILL DEPEND ON HOW CONVECTION UPSTREAM
UNFOLDS. HELD WITH INHERITED BROAD BRUSH VCTS MENTION BUT SHOULD BE
ABLE TO NARROW DOWN AND REFINE THAT TIMING LATER THIS EVENING.
CONVECTION MAY PERSIST/RE-DEVELOP AFTER 12Z TOMORROW BUT
CONFIDENCE IS TOO LOW FOR INCLUSION IN THE TAF AT THIS TIME.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...JT
SHORT TERM...AGD
LONG TERM...MCD
AVIATION...AGD
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
201 PM EDT WED APR 8 2015
.SYNOPSIS...
ISSUED AT 1003 AM EDT WED APR 8 2015
SEVERAL PERIODS OF RAIN WILL BE POSSIBLE DURING THE NEXT COUPLE
OF DAYS. A STATIONARY FRONT OVER CENTRAL PORTIONS OF INDIANA AND
OHIO IS EXPECTED TO LIFT SLOWLY NORTH INTO MICHIGAN TONIGHT.
SCATTERED THUNDERSTORMS ARE POSSIBLE NEAR THE FRONT TODAY WITH
SHOWERS AND THUNDERSTORMS LIKELY BECOMING NUMEROUS TONIGHT. A COLD
FRONT WILL APPROACH THE AREA ON THURSDAY LIKELY CAUSING ANOTHER
ROUND OF THUNDERSTORMS. HIGHS TODAY ARE EXPECTED TO RANGE FROM
THE MID 50S NORTH OF THE FRONT IN SOUTHERN MICHIGAN TO THE LOW 70S
SOUTH OF THE FRONT SOUTH OF US 30. LOWS TONIGHT WILL BE IN THE
50S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 419 AM EDT WED APR 8 2015
THE CLOUDY...COOL PATTERN CONTINUES AS WE MAINTAIN OUR POSITION
NORTH OF THE STATIONARY FRONT. A WEAK SHORTWAVE HAS TRIGGERED SOME
CONVECTION IN SE IOWA/ WESTERN ILLINOIS JUST NORTH OF THIS
STATIONARY FRONT. THE STORMS SEEM TO BE STRUGGLING WITH EASTWARD
EXTENT...LIKELY DUE TO A SLIGHTLY STRONGER CAP AT 650MB AND LESS
INFLUENCE FROM THE MID LEVEL WAVE. GIVEN THE REMAINING UNCERTAINTY
WITH THE EVOLUTION OF THIS CONVECTIVE COMPLEX AS IT MOVES
EASTWARD...HAVE KEPT POPS IN THE HIGH CHANCE RANGE.
EXPECT A LULL IN THE PRECIPITATION DURING THE AFTERNOON ON TODAY
AS WEAK SHORTWAVE RIDGING BUILDS IN AHEAD OF THE NEXT SHORTWAVE TO
EJECT OUT OF THE CENTRAL PLAINS. THIS WILL ALSO ALLOW FOR A LONG
AWAITED SHIFT NORTHWARD IN THE FRONTAL BOUNDARY. THIS PSEUDO WARM
FRONTAL SURGE WILL CREATE SIGNIFICANT BUST POTENTIAL FOR HIGH
TEMPERATURES ON TODAY. AREAS SOUTH OF THE SURFACE FRONT WILL
LIKELY WARM INTO THE LOW 70S WITH AREAS NORTH OF THE FRONT REMAINING
IN THE MID 50S. THE EXACT PROGRESSION OF THIS FRONT NORTHWARD WILL
DICTATE EXACTLY WHO SEES THE WARMER TEMPERATURES...BUT THE LATEST
HIRES GUIDANCE PUTS THE MAX NORTHWARD PROGRESSION RIGHT ALONG US30.
REGARDLESS OF THE EXACT PLACEMENT OF THIS FRONT...ITS PRESENCE
ACROSS OUR AREA MEANS WE WILL BE FAVORABLE FOR THUNDERSTORM
DEVELOPMENT DURING THE EVENING AND INTO THE OVERNIGHT HOURS. THERE
IS SIGNIFICANT UNCERTAINTY WRT TIMING OF STORMS ACROSS THE AREA. NAM
AND RAP HAVE A DECENT SHORTWAVE SPAWNING STORMS NORTH OF SAINT LOUIS
DURING THE AFTERNOON AND MOVING THAT MCS THROUGH OUR AREA AROUND
00Z. ONLY GLOBAL GUIDANCE WHICH EVEN HINTS AT A WAVE MOVING THROUGH
AT THAT TIME IS THE GEM AND THEREFORE GLOBAL GUIDANCE HOLDS OFF ON
CONVECTION UNTIL AFTER MIDNIGHT. IR SATELLITE DOES SHOW SOME COOLER
CLOUD TOPS IN SW KANSAS WHERE THIS SW IS CURRENTLY SUPPOSED TO
BE...SO AM INCLINED TO BELIEVE THE HIRES GUIDANCE AND DISCOUNT THE
GLOBAL GUIDANCE AS LACKING THE RESOLUTION TO PROPERLY RESOLVE THIS
WAVE. SEVERE RISK DOES EXIST WITH ANY STORMS THAT DO DEVELOP IN THIS
AFTERNOON TIMEFRAME GIVEN 40 TO 50 KNOTS OF DEEP LAYER SHEAR AND
1500 TO 2000 J/KG OF SBCAPE SOUTH OF THE SURFACE FRONT. EVEN IF THE
EARLY EVENING STORM DEVELOPMENT ON THE HIRES GUIDANCE DOESN`T
MATERIALIZE...THERE WILL STILL BE AN ISOLATED RISK OF SEVERE WEATHER
DURING THE OVERNIGHT HOURS GIVEN THE ~2000 J/KG OF MUCAPE AND 30
KNOT LLJ WITH THE REMAINING PRESENCE OF 35 TO 45 KNOTS OF DEEP LAYER
SHEAR.
&&
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 419 AM EDT WED APR 8 2015
PRIMARY CONCERNS FOR THE LONG TERM WILL CENTER ON CONVECTIVE/SEVERE
POTENTIAL THURSDAY/THURSDAY NIGHT...FOLLOWED BY RENEWED PRECIP
CHANCES EARLY NEXT WEEK.
SHOWERS/STORMS WILL LIKELY BE ONGOING THURSDAY MORNING AS UPPER JET
STREAK ASSOCIATED WITH SUBTROPICAL JET ENCROACHES ON THE OHIO RIVER
VALLEY. AXIS OF 40-50 KNOT SOUTHWESTERLY LOW LEVEL FLOW NOSING INTO
THE AREA BY MIDDAY WILL ALLOW FOR APPRECIABLE LOW/MID LEVEL
MOISTURE ADVECTION. MOISTURE CONVERGENCE AT NOSE OF STRONGER LOW
LEVEL FLOW SHOULD ALLOW POCKET OF PWATS NEAR 1.5 INCHES TO TRACK
ACROSS FORECAST AREA THURSDAY MORNING WITH AMPLE ELEVATED MOISTURE
FOR SHOWERS AND EMBEDDED THUNDER. POTENTIAL OF SOME LOCALLY HEAVIER
RAINFALL AMOUNTS STILL APPEARS TO BE INTACT THROUGH THURSDAY MORNING
IN ASSOCIATION WITH THIS FORCING ALONG WITH POTENTIAL OF SOME HAIL
GIVEN ELEVATED INSTABILITY AND RELATIVELY LOW FREEZING/WBZ ZERO
HEIGHTS BETWEEN 9-10K FT.
SOME DEGREE OF UNCERTAINTY REMAINS REGARDING CONVECTIVE EVOLUTION
THURSDAY AFTERNOON AND ASSOCIATED IMPACTS ON INSTABILITY MAGNITUDES
DURING PEAK HEATING. ATTENTION FOR THURSDAY AFTERNOON/NIGHT WILL
SHIFT UPSTREAM TO MORE ROBUST EASTERN PACIFIC WAVE WHICH SHOULD
ACQUIRE NEGATIVE TILT ACROSS THE WESTERN GREAT LAKES THURSDAY
EVENING. FRONTAL CONVERGENCE AND LEADING EDGE OF MID LEVEL DRY SLOT
SHOULD REGENERATE POTENTIALLY VIGOROUS CONVECTIVE DEVELOPMENT
ACROSS ILLINOIS DURING THE AFTERNOON...POSSIBLY TRACKING INTO
WESTERN PORTIONS OF LOCAL AREA THURSDAY EVENING. EXTENT OF ANY
THINNING CLOUD COVER THURSDAY AFTERNOON/LOW LEVEL TEMP TRENDS WILL
HAVE A BIG IMPACT ON INSTABILITY MAGNITUDES. GIVEN STRENGTH OF
BACKGROUND WIND FIELDS...A WIND THREAT MAY EVOLVE THURSDAY EVENING
EVEN IF AFTERNOON INSTABILITY RECOVERY IS SOMEWHAT LIMITED. AS
MENTIONED IN PREVIOUS FORECAST...A SOMEWHAT HIGHER SEVERE THREAT MAY
UNFOLD IF GREATER LATE AFTERNOON INSTABILITY CAN BE REALIZED GIVEN
SUBSTANTIAL SHEAR PROFILES...AND IN LIGHT OF DIFFERENTIAL
MOISTURE ADVECTION IMMEDIATELY PRECEDING SFC FRONT THURSDAY NIGHT
ASSOCIATED WITH THE DRY SLOT. SPC DAY2 OUTLOOK HAS MAINTAINED HIGHER
SVR PROBS ACROSS WESTERN THIRD/HALF OF AREA...WITH POSSIBILITY OF
WEAK NEAR SFC DIURNAL COOLING LATER THURSDAY EVENING DIMINISHING
INSTABILITY MAGNITUDES A BIT ACROSS THE EAST. ONLY TWEAK TO PREVIOUS
FORECAST WAS TO SLIGHTLY SPEED UP TIMING OF WEST TO EAST POP
REDUCTION LATER THURSDAY NIGHT FOLLOWING COLD FRONT PROGRESSION.
DID MAINTAIN SLIGHT CHANCE RAIN SHOWER POPS ACROSS THE FAR NORTH/FAR
EAST EARLY FRIDAY MORNING GIVEN LINGERING MID/UPPER FORCING WITH A
SERIES OF SMALLER SCALE WAVES ROTATING THROUGH LONGWAVE TROUGH...BUT
ADDITIONAL PRECIP AMOUNTS ACROSS THESE LOCATIONS SHOULD BE QUITE
LIGHT. BREEZY/WINDY CONDITIONS CAN ALSO BE EXPECTED WITH DEEPER POST
FRONTAL MIXING LATE THURSDAY NIGHT INTO FRIDAY. IT STILL APPEARS AS
THOUGH THE FRIDAY NIGHT THROUGH SUNDAY PERIOD SHOULD BE DRY WITH
NEAR SEASONABLE TEMPS UNDER INFLUENCE OF MID/UPPER LEVEL RIDGING.
LOW LEVEL ANTICYCLONE TO DEPART TO THE EAST SUNDAY NIGHT INTO MONDAY
ALLOWING FOR A FAIRLY QUICK TRANSITION TO STRONGER LOW LEVEL
MOISTURE TRANSPORT FOR MONDAY. GOOD MOISTURE AVAILABILITY AND
APPROACH OF CUT-OFF SOUTHERN STREAM PV ANOMALY FOR TUE/WED SHOULD
KEEP CHANCES OF SHOWERS AND STORMS GOING THROUGH THE END OF THE
PERIOD AS THIS WAVE EVENTUALLY DAMPENS ACROSS THE AREA. THIS PATTERN
WILL ALSO BE CONDUCIVE FOR SHARPLY MODERATING TEMPERATURES ONCE
AGAIN FOR EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 200 PM EDT WED APR 8 2015
SHORTWAVE RIDGING IN THE WAKE OF MORNING CONVECTION IS CURRENTLY
PROVIDING A BREAK IN PRECIP ALONG WITH AN AREA OF VFR CONDITIONS
ACROSS NORTHERN INDIANA. PRECIP AND LOW LEVEL MOISTURE WILL RETURN
TONIGHT AS ANOTHER SHORTWAVE TROUGH MOVES OVER THE AREA AND THE
LLJ RAMPS UP. CONFIDENCE IN TIMING AND COVERAGE OF THUNDERSTORMS
IS LOW AT THIS POINT AND WILL DEPEND ON HOW CONVECTION UPSTREAM
UNFOLDS. HELD WITH INHERITED BROAD BRUSH VCTS MENTION BUT SHOULD BE
ABLE TO NARROW DOWN AND REFINE THAT TIMING LATER THIS EVENING.
CONVECTION MAY PERSIST/RE-DEVELOP AFTER 12Z TOMORROW BUT
CONFIDENCE IS TOO LOW FOR INCLUSION IN THE TAF AT THIS TIME.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...JT
SHORT TERM...BENTLEY
LONG TERM...MARSILI
AVIATION...AGD
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1257 PM EDT WED APR 8 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 304 AM EDT WED APR 8 2015
A FRONTAL SYSTEM IS EXPECTED TO REMAIN ACROSS THE AREA THROUGH
TONIGHT...BEFORE LIFTING OFF TO THE NORTH ON THURSDAY. A COLD FRONT
IS EXPECTED TO MOVE THROUGH THE AREA THURSDAY NIGHT. IN THE WAKE OF
THIS FRONT...HIGH PRESSURE WILL MOVE INTO THE AREA OVER THE WEEKEND.
ANOTHER FRONTAL SYSTEM MAY AFFECT THE AREA BY EARLY NEXT WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 1028 AM EDT WED APR 8 2015
THERE SHOULD BE A BREAK IN THE ACTION THANKS TO STABILIZATION FROM
THIS MORNINGS SYSTEM. HOWEVER THE HRRR REINTRODUCES PRECIPITATION
DURING THE AFTERNOON AS A WARM HUMID FLOW CONTINUES FROM THE
SOUTHWEST. ALSO...BASED ON WHAT WE SEE IN ILLINOIS THERE MAY WELL
BE SOME BREAKS EARLY IN THE AFTERNOON WHICH WOULD LEAD TO RAPID
DESTABILIZATION.
ALL THINGS CONSIDERED...LIKELY POPS SEEM BEST OVER THE SOUTHERN CWA
MOST OF THE AFTERNOON AND OVER THE ENTIRE CWA BY LATER AFTERNOON.
FORECAST TEMPERATURES FOR TODAY MIGHT BE TOO HIGH. HOWEVER WITH EVEN
A FEW BREAKS THE THERMOMETER WILL ROCKET UP. HIGHS FROM THE EARLIER
FORECAST WILL BE KEPT IN THE UPDATE.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
ISSUED AT 304 AM EDT WED APR 8 2015
SURFACE WAVE EXPECTED TO MOVE ACROSS NORTHERN INDIANA
TONIGHT...WHICH MAY ALLOW FOR THE FRONT TO SAG BACK TO THE SOUTH
TEMPORARILY. MODELS SUGGEST A STRONGER LOW LEVEL JET...ON THE ORDER
OF AROUND 40 KTS...WILL BE NOSING TOWARDS WESTERN INDIANA LATE
TONIGHT. AS A RESULT...THINK THE POTENTIAL FOR CONVECTION WILL BE
HIGHER TONIGHT. WILL GO WITH HIGH POPS OVER THE NORTHERN AND
CENTRAL ZONES...TAPERING OFF TO CHANCE POPS OVER THE SOUTH. LAPSE
RATES AND DEEP LAYER SHEAR SUGGEST POTENTIAL FOR ORGANIZED SEVERE
STORMS TONIGHT.
WILL CONTINUE WITH HIGH POPS ON THURSDAY AND THURSDAY NIGHT AS
PROGGED LOW LEVEL JET OF 45-50 KTS INTERACTS WITH AN APPROACHING
UPPER TROUGH AND SURFACE COLD FRONT. MAY BE A LULL IN THE
PRECIPITATION THREAT THURSDAY AFTERNOON AS THE LOCAL AREA GETS
FURTHER INTO THE WARM SECTOR BEFORE COLD FRONT ARRIVES THURSDAY
EVENING...BUT WON/T GET TOO DETAILED IN THE TIMING AT THIS POINT.
APPEARS DEEP SHEAR WILL BE MAXIMIZED OVER THE AREA THURSDAY NIGHT AS
THE CORE OF THE MID LEVEL JET APPROACHES. POTENTIAL FOR SEVERE
WILL CONTINUE UNTIL FRONTAL PASSAGE LATE THURSDAY NIGHT.
FRONTAL SHOULD BE FAR ENOUGH OFF TO THE EAST BY FRIDAY MORNING TO GO
DRY FOR FRIDAY AND FRIDAY NIGHT.
LOW LEVEL THICKNESS PROGS SUGGEST THE GFS MOS TEMPERATURE GUIDANCE
IN THE LATER PERIODS LOOK REASONABLE AT THIS POINT...ALTHOUGH THE
LOWS FRIDAY MORNING LOOK TOO WARM IN THE WAKE OF THE COLD FRONT.
WILL LOWER THEM ABOUT 3-5 DEGREES IN THAT PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
ISSUED AT 304 AM EDT WED APR 8 2015
DRY PLEASANT WEATHER EXPECTED FOR MUCH OF THE WEEKEND AS HIGH
PRESSURE MOVES THROUGH THE OHIO VALLEY. AN UPPER TROUGH WILL BE IN
THE PROCESS OF MOVING AWAY TO THE EAST ON SATURDAY...WITH RIDGING
ALOFT AND WARM ADVECTION DEVELOPING FOR THE SECOND HALF OF THE
WEEKEND. HIGHS IN THE UPPER 50S AND LOWER 60S SATURDAY WILL WARM
PRIMARILY INTO THE 60S FOR SUNDAY.
UNSETTLED WEATHER THEN RETURNS FOR MUCH OF THE REST OF THE EXTENDED.
BROAD UPPER TROUGH EXPANDING ACROSS THE PACIFIC NORTHWEST AND
NORTHERN PLAINS WILL SERVE TO FLATTEN THE RIDGE BY LATE WEEKEND WITH
MOISTURE INCREASING AS A WEAK FRONT MOVES INTO THE GREAT LAKES.
COULD SEE A FEW SHOWERS BY SUNDAY AFTERNOON OVER WESTERN COUNTIES
WITH MORE EXTENSIVE PRECIP COVERAGE SUNDAY NIGHT AS THE SYSTEM TAPS
INTO A GULF MOISTURE FETCH. FAST MOVING UPPER LOW TRACKING WITH THE
SUBTROPICAL JET WILL MOVE FROM BAJA CALIFORNIA EARLY SUNDAY INTO THE
SOUTHERN PLAINS BY LATE MONDAY WITH SURFACE CYCLOGENESIS BY MONDAY
NIGHT. WARM FRONT SETS UP INTO THE OHIO VALLEY LATE MONDAY THROUGH
TUESDAY AND WILL PROMOTE ANOTHER PERIOD WITH SHOWERS AND
THUNDERSTORMS AS THE SURFACE WAVE TRACKS INTO THE REGION BY EARLY
WEDNESDAY. WILL CARRY CHANCE POPS FROM SUNDAY NIGHT INTO MIDWEEK.
HIGHS WILL LARGELY REMAIN IN THE 60S FOR MONDAY AND TUESDAY AS
CLOUDS AND RAINFALL LIKELY TO LIMIT TEMP RISES.
&&
.AVIATION /DISCUSSION FOR 081800Z TAFS/...
ISSUED AT 1246 PM EDT WED APR 8 2015
HIGH UNCERTAINTY IN FORECAST. MORNING CONVECTION HAS LAID DOWN
OUTFLOW BOUNDARIES WHILE SOUTHWEST FLOW PUMPING WARMER AND MORE
HUMID AIR TOWARD TAF SITES HAS RESULTED IN MVFR DECK 1500-2000 FT.
THINKING IS THIS SITUATION IS WARM FRONTAL LIKE AND AS BOUNDARY
PUSHES BACK NORTHEAST AND SUN CONTINUE WORKING ON CLOUDS THIS MVFR
DECK SHOULD SCATTER TO A LAYER AROUND 2500 FEET.
OTHER FACTOR IS THE CIRRUS DEBRIS FROM MISSOURI STORMS HAS
OVERSPREAD INDIANA AND ILLINOIS AND SERVING TO LIMIT CUMULUS GROWTH.
CERTAINLY SURFACE BOUNDARIES AVAILABLE TO HELP WITH LIFT BUT MOST
MODELS KEY ON NEXT UPPER SUPPORT ARRIVING AFTER 090600Z. THUS ANY
CONVECTION PRIOR WILL BE ISOLATED OR SCATTERED...FOCUSED ON MESO
BOUNDARY AND DRIVEN BY WHAT HEATING MAY OCCUR TODAY. ANTICIPATE
THUNDERSTORM COMPLEX WITH WIDESPREAD STORMS TO ARRIVE AFTER
090600Z WITH UPPER SUPPORT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JAS
NEAR TERM...JK
SHORT TERM...JAS
LONG TERM....RYAN
AVIATION...TUCEK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS WICHITA KS
401 PM CDT WED APR 8 2015
.MESOSCALE DISCUSSION...
ISSUED AT 401 PM CDT WED APR 8 2015
THE INITIAL CONVECTION IS ABOUT TO EXIT THE FORECAST AREA.
REGIONAL RADAR SHOWING THE FRONT BEGINNING TO RETREAT TO THE NORTH
AND AT 2055Z WAS LOCATED FROM ANTHONY TO MULVANE TO EMPORIA.
THE 20Z RAP SHOWS THE RETREAT OF THE FRONT VERY SLOWLY NORTHWARD.
DO NOT THINK IT WILL GET CARRIED AWAY AND GO TOO FAR NORTH GIVEN
THE STRENGTH OF THE COLD POOL. THROUGH 01Z...LOW LEVEL CAPE AND
SHEAR WILL INCREASE...PRODUCING AN ENVIRONMENT THAT WILL FAVOR
TORNADOES...SOME OF WHICH COULD BE SIGNIFICANT.
CONVECTION IS ALREADY DEVELOPING OVER THE TEXAS PANHANDLE IN
RESPONSE TO THE UPPER LEVEL DISTURBANCE MOVING INTO THE REGION.
THIS WILL BE THE DISTURBANCE THAT LEADS TO TONIGHTS SIGNIFICANT
SEVERE WEATHER THREAT.
THINKING TONIGHT REMAINS ON TRACK. WHERE STORMS WILL BE ARE
CONTINGENT TO THE LOCATION OF THE FRONT. WILL REMAIN VIGILANT IN
TRACKING THIS.
KRC
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 245 PM CDT WED APR 8 2015
THIS EVENING-TONIGHT: LATEST SURFACE ANALYSIS SHOWS MAIN SURFACE
BOUNDARY LOCATED JUST TO THE SE OF ICT METRO...MAINLY FROM EUREKA TO
MULVANE TO WELLINGTON. THE INITIAL ROUND OF CONVECTION HAS ALREADY
BEGUN OVER SRN KS...WITH MULTICELL STORMS PRODUCING MAINLY HAIL AND
DAMAGING WINDS. THIS INITIAL ROUND OF STORMS WILL STAY IN THE WARM
SECTOR ACROSS SE KS FOR THE EARLY AFTERNOON HOURS. WITH THE MAIN
CONCERN FROM THIS ROUND BEING LARGE HAIL AND DAMAGING WINDS GIVEN
THE UNSTABLE AIRMASS AND FAVORABLE BULK SHEAR.
LATEST SHORT TERM HI-RES MODELS CONTINUE TO SHOW THE BOUNDARY
RETROGRADING BACK TO THE NORTH EARLY THIS EVENING BETWEEN 21Z-02Z...
WITH A SIGNIFICANT INCREASE OF LOW LEVEL CAPE BACK TOWARDS THE KICT
METRO. THIS IN CONJUNCTION WITH THE INCREASE IN BULK SHEAR FROM THE
INCOMING DISTURBANCE COUPLED WITH THE LOW LEVEL JET WILL PRODUCE A
SCENARIO VERY FAVORABLE FOR TORNADIC SUPERCELLS TO DEVELOP ALONG THE
DRY LINE AS IT SHARPENS FOR AREAS TO THE WEST AND SW OF SOUTH
CENTRAL KS. THIS WILL LEAD TO A SECOND POSSIBLY MORE SIGNIFICANT
CHANCE OF STORMS FOR LATER THIS EVENING WELL AFTER DARK. LATEST HI-
RES MODEL CONTINUE TO SHOW 0-8KM SHEAR IS VERY FAVORABLE FOR
SUPERCELLS AND POSSIBLE LONG TRACK TORNADOES. INCREASED MLCAPE TO
2000-2500 J/KG AND LOWERING LCL LEVELS WOULD ALSO SUGGEST A
STRONG TORNADO THREAT AS WELL. SO THIS SETUP WOULD STILL LEAD TO
HIGH LIKELYHOOD OF THE TORNADO THREAT CONTINUING WELL AFTER DARK
FOR AREAS AREAS ACROSS SOUTH CENTRAL KS...MAINLY ALONG OR SOUTH OF
HIGHWAY 54/400.
EXPECT THE SEVERE CONVECTION TO CONTINUE FOR THE OVERNIGHT
HOURS...WITH PROGRESSION OF THE STORMS TO THE EAST INTO THE FLINT
HILLS AND SOUTHEAST KS. DEEP LAYER SHEAR LOOKS TO WANE SOME AFTER
MIDNIGHT...WHICH WILL LIKELY SHIFT THE SEVERE WEATHER MODE TO MORE
OF A LARGE HAIL AND DAMAGING WIND CHANCE.
THU: COULD SEE SOME LINGERING STORMS ACROSS PORTIONS OF SOUTHEAST
KS IN THE MORNING HOURS AS THE DRY LINE/BOUNDARY SURGES EAST INTO
WRN MO. IT NOT COMPLETELY OUT OF THE REALM OF POSSIBILITY THAT
SOME LINGERING STRONG STORMS WILL BE OVER SE KS...BUT THIS CHANCE
WILL BE SHORT LIVED. EXPECT THE THU AFTERNOON SEVERE THREAT TO
OVER EXTREME SE KS AND MAINLY IN SW MO. WITH THE REST OF THE
REGION SEEING NICE WEATHER RETURN TO THE AREA...WITH DRIER AIR
MOVING INTO THE AREA.
FRI-EARLY SAT: A COUPLE OF NICE DAY EXPECTED FOR FRI AND EARLY SAT
AS A LARGE AREA OF HIGH PRESSURE MOVES ACROSS THE PLAINS INTO THE
SRN PLAINS. THIS WILL LEAD TO NEAR SEASONAL TEMPS AND SUNNY SKIES
IN MOST LOCATIONS. AS SATURDAY PROGRESSES...LOW LEVEL MOISTURE WILL
RAPIDLY RETURN TO THE AREA FOR AREAS WEST OF THE FORECAST AREA FOR
SAT AFTERNOON. COULD SEE SHOWERS AND THUNDERSTORMS DEVELOP TO THE
WEST OF THE AREA AND POSSIBLY MOVE INTO SOME OF THE WRN PORTIONS OF
COUNTY WARNING AREA BY SAT EVENING.
SAT NIGHT: ISENTROPIC LIFT AND MOISTURE RETURN WILL CONTINUE OVER
THE WRN HALF OF THE FORECAST AREA FOR SAT NIGHT. THIS MAY LEAD TO
A CHANCE OF SHOWERS AND THUNDERSTORM COVERAGE INCREASING ACROSS
MOST OF THE AREA FOR SAT NIGHT.
KETCHAM
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 245 PM CDT WED APR 8 2015
MEDIUM RANGE MODELS DO DIFFER SOME ON HOW SUN AND MON WILL PLAY OUT.
BUT BOT MODELS SUGGEST ANOTHER CHANCE OF THUNDERSTORMS ON
SUNDAY...WITH POSSIBLE STRONG TO SEVERE STORMS. THE ECMWF LOOKS TO
CLEAR THINGS OUT ON MON...WHILE THE GFS SUGGESTS A BOUNDARY MAY BE
STATIONARY ACROSS SRN KS FOR MON.
KETCHAM
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1208 PM CDT WED APR 8 2015
CONVECTION NOW DEVELOPING OVER OKLAHOMA WILL MOVE NORTHEAST INTO
THE AIRSPACE AND CONTINUE WITH SEVERAL ROUNDS THROUGH 6Z. THIS
WILL AFFECT ALL AIRPORTS AND FIELDS ALONG AND SOUTHEAST OF KSLN-
KVNX. THESE STORMS WILL BE SEVERE AND SHOULD BE AVOIDED.
FOG...WHICH CONTINUES TO AFFECT KHUT...KRSL...KSLN HAS BEEN SLOW
TO BURN OFF. THINK IT SHOULD BE GONE BY 21Z. VFR CONDITIONS SHOULD
PERSIST THROUGH 03Z...WITH FOG REDEVELOPMENT THERE POSSIBLE
THROUGH 12Z.
THE COLD FRONT WILL CLEAR THE AREA BY 14Z.
&&
.FIRE WEATHER...
ISSUED AT 245 PM CDT WED APR 8 2015
MAIN FIRE WEATHER CONCERNS LOOK TO ON THURSDAY.
EVEN WITH PLENTY OF LOW LEVEL MOISTURE...VERY HIGH FIRE DANGER WILL
BE IN PLACE OVER SOUTH CENTRAL AND SE KS DUE TO GUSTY SOUTH WINDS.
HOWEVER...THE CRITICAL FIRE WEATHER DAY LOOKS TO BE THU. THIS IS
WHEN STRONG NW WINDS WILL BE IN PLACE BY THE AFTERNOON HOURS ALONG
WITH RH`S IN THE 35-45 PERCENT RANGE. WIND SPEEDS THU AFTERNOON
WILL BE IN THE 20-30 MPH RANGE WITH HIGHER GUSTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 56 71 39 68 / 30 10 0 0
HUTCHINSON 52 67 37 68 / 30 10 0 0
NEWTON 54 67 38 67 / 30 10 0 0
ELDORADO 60 69 39 68 / 40 10 10 0
WINFIELD-KWLD 61 72 40 68 / 30 10 0 0
RUSSELL 46 63 35 67 / 20 10 10 0
GREAT BEND 46 64 35 67 / 10 10 0 0
SALINA 50 65 35 68 / 30 20 10 0
MCPHERSON 51 66 36 67 / 30 10 10 0
COFFEYVILLE 65 76 42 68 / 40 30 10 0
CHANUTE 64 73 41 68 / 50 30 10 0
IOLA 63 72 40 67 / 50 30 10 0
PARSONS-KPPF 64 74 41 68 / 50 30 10 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
348 PM CDT WED APR 8 2015
...UPDATED FOR LONG TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 150 PM CDT WED APR 8 2015
A SURFACE BOUNDARY WILL SLOWLY LIFT NORTH INTO EXTREME SOUTHERN
KANSAS LATE THIS AFTERNOON AND EARLY THIS EVENING. A DRYLINE WILL
EXTEND SOUTH OF THIS BOUNDARY ACROSS BARBER COUNTY INTO NORTHERN
OKLAHOMA. GIVEN THE INSTABILITY EXPECTED AHEAD OF AN UPPER LEVEL
DISTURBANCE WHICH WILL BE CROSSING CENTRAL KANSAS LATE THIS
AFTERNOON THERE WILL BE A CHANCE FOR SOME CONVECTION TO DEVELOP
ALONG EITHER SURFACE BOUNDARY. BASED ON THE 0-6KM SHEAR FORECAST
AT 00Z THURSDAY ANY STORM THAT MAY DEVELOP IN THIS AREA SHOULD
RAPIDLY DEVELOP AND MAY BECOME SEVERE BEFORE IT MOVES EAST OF
PRATT AND BARBER COUNTY. AT THIS TIME THE MAIN HAZARD LATE TODAY
WILL BE 2 INCH HAIL AND STRONG GUSTY WINDS.
FURTHER WEST CLEAR SKIES, WARM TEMPERATURES, AND DEWPOINTS IN THE
30S HAVE RESULT IN RELATIVE HUMIDITY VALUES FALLING BACK INTO THE
TEENS AT 00F 18Z. GIVEN THAT THE CLEARING TREND CURRENTLY
OCCURRING WILL CONTINUE, BASED ON SATELLITE LOOP, AND THE 850MB
MIX DOWN TEMPERATURES AT 00Z THURSDAY IT APPEARS THAT CRITICAL
FIRE WEATHER CONDITIONS WILL STILL EXIST LATE TODAY. AS A RESULT
WILL LEAVE THE CURRENT RED FLAG WARNING GOING FOR PORTIONS OF
SOUTHWEST KANSAS.
FOR THE REMAINDER OF THE OVERNIGHT PERIOD...THE SURFACE BOUNDARY,
WHICH WAS LOCATED OVER SOUTHWEST KANSAS LATE THIS AFTERNOON/EARLY
EVENING, WILL MOVE SOUTH AS AN UPPER LEVEL TROUGH CROSSES THE
CENTRAL HIGH PLAINS. BASED ON THE SURFACE DEW POINTS EXPECTED
EARLY THURSDAY MORNING, SOME MID OR HIGH CLOUDS PRECEDING THE
UPPER LEVEL TROUGH, AND A DEVELOPING NORTHWESTERLY FLOW THE
PREVIOUS FORECAST STILL APPEARS ON TRACK WITH LOWS BOTTOMING OUT
MAINLY IN THE 40S ACROSS WESTERN KANSAS. LOWS IN THE 50 TO NEAR 55
DEGREE RANGE WILL BE LIKELY ACROSS SOUTH CENTRAL KANSAS.
THE UPPER LEVEL TROUGH WILL CROSS WESTERN KANSAS EARLY THURSDAY
MORNING AS A SURFACE HIGHS BEGINS TO BUILD INTO NORTHWESTERN
KANSAS/NORTHEAST COLORADO. OVER WESTERN KANSAS GUSTY NORTHWEST
WINDS AT 20 TO NEAR 30 MPH ARE EXPECTED BY THE EARLY AFTERNOON
BASED ON 0-1KM WINDS RANGING FROM 25 TO NEAR 35 KNOTS, AND THE
MEAN MIXED LAYER WINDS AT 18Z AND 21Z RANGING FROM 30 TO 35KNOTS.
BASED ON THE MIXING POTENTIAL THURSDAY AFTERNOON FROM THE BUFR
NAM, AND THE 850MB TEMPERATURES AT 00Z FRIDAY WILL TREND TOWARDS
THE WARMER GUIDANCE ACROSS WESTERN KANSAS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 327 PM CDT WED APR 8 2015
COOL, SURFACE HIGH PRESSURE WILL BUILD INTO WESTERN KANSAS
THROUGH FRIDAY. WITH LIGHT WINDS THURSDAY NIGHT, TEMPERATURES WILL
FALL INTO THE 30S, WITH SOME READINGS CLOSE TO FREEZING FROM DODGE
CITY WESTWARD AND NORTHWARD. HIGHS WILL BE IN THE 60S FRIDAY.
THE MODELS, ESPECIALLY THE ECMWF/GFS, ARE INDICATING A SHORTWAVE
TROUGH OVER THE DESERT SOUTHWEST PROGRESSING INTO THE SOUTHERN
HIGH PLAINS IN NEGATIVE TILT FASHION BY SUNDAY BEFORE CLOSING OFF
OVER THE SOUTHERN PLAINS BY MONDAY. THE GEM IS FATHER SOUTH WITH
THE UPPER LOW, WITH LESS PRECIPITATION OVER WESTERN KANSAS. WITH
PLENTY OF LOW LEVEL MOISTURE IN PLACE, CHANCES FOR WIDESPREAD SHOWERS
AND THUNDERSTORMS ARE GOOD ON MONDAY. AHEAD OF THIS SYSTEM, A FEW
SHOWERS AND STORMS ARE POSSIBLE SATURDAY AFTERNOON AND NIGHT ALONG
THE LEE TROUGH AS WELL BUT WITH LIMITED INSTABILITY, .
HIGH TEMPERATURES WILL GENERALLY BE MILD, BUT MAY BE HELD DOWN
MONDAY DUE TO CLOUDS AND PRECIPITATION. OVERNIGHT LOWS WILL OF
COURSE BE INCREASING THROUGH MONDAY DUE TO THE LEE TROUGHING,
SOUTH WINDS AND HIGHER DEWPOINTS.
A MORE AMPLIFIED UPPER LEVEL TROUGH WILL BEGIN TO DEVELOP OVER
THE WESTERN UNITED STATES MONDAY THROUGH WEDNESDAY OF NEXT WEEK,
RESULTING IN LEE TROUGHING, SOUTHERLY WINDS AND WARMER
TEMPERATURES TUESDAY. GIVEN A POSITIVE TILT TO THIS UPPER LEVEL
SYSTEM AS DEPICTED IN THE MODELS, SEVERE WEATHER CHANCES MAY BE
HIGHER ACROSS EASTERN KANSAS DUE TO MORE VEERED LOW LEVEL WINDS,
WITH SOME CHANCES FOR SHOWERS AND THUNDERSTORMS BY THE MIDDLE OF
NEXT WEEK OVER WESTERN KANSAS AS THE COLD FRONT APPROACHES. BEHIND
THIS FRONT, MUCH COOLER WEATHER IS POSSIBLE BY LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1215 PM CDT WED APR 8 2015
STATUS AND FOG WILL ERODE THIS AFTERNOON AS A SURFACE BOUNDARY
BEGINS TO SLOWLY MOVE NORTH ACROSS SOUTHWEST KANSAS. AT THIS TIME
BASED ON THE LATEST TRENDS FROM THE HRRR AND RAP WILL GRADUALLY
IMPROVE CEILING WITH VFR CONDITIONS DEVELOPING BETWEEN 20Z AND
22Z AT DDC AND GCK. HYS WILL IMPROVE TO MVFR. VFR CONDITIONS AT
HYS IS EXPECTED TO DEVELOP TOWARDS 00Z THURSDAY. THE PREVAILING
WIND THIS AFTERNOON NORTH OF THIS FRONT WILL BE NORTHERLY AT 10
KNOTS OR LESS. NORTHWEST WINDS WILL DEVELOP OVERNIGHT AS A COLD
FRONT CROSSES WESTERN KANSAS. THE NORTHWESTERLY WINDS WILL
INCREASE BY LATE MORNING THURSDAY AS STRONGER BOUNDARY LAYER WINDS
MIXED DOWN TO THE SURFACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 46 66 35 67 / 10 10 0 0
GCK 42 64 34 68 / 10 10 0 0
EHA 42 65 35 68 / 10 10 0 0
LBL 44 67 36 68 / 20 10 0 0
HYS 45 62 34 67 / 20 10 0 0
P28 53 72 38 69 / 20 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR KSZ084>086.
&&
$$
SHORT TERM...BURGERT
LONG TERM...FINCH
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
156 PM CDT WED APR 8 2015
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 150 PM CDT WED APR 8 2015
A SURFACE BOUNDARY WILL SLOWLY LIFT NORTH INTO EXTREME SOUTHERN
KANSAS LATE THIS AFTERNOON AND EARLY THIS EVENING. A DRYLINE WILL
EXTEND SOUTH OF THIS BOUNDARY ACROSS BARBER COUNTY INTO NORTHERN
OKLAHOMA. GIVEN THE INSTABILITY EXPECTED AHEAD OF AN UPPER LEVEL
DISTURBANCE WHICH WILL BE CROSSING CENTRAL KANSAS LATE THIS
AFTERNOON THERE WILL BE A CHANCE FOR SOME CONVECTION TO DEVELOP
ALONG EITHER SURFACE BOUNDARY. BASED ON THE 0-6KM SHEAR FORECAST
AT 00Z THURSDAY ANY STORM THAT MAY DEVELOP IN THIS AREA SHOULD
RAPIDLY DEVELOP AND MAY BECOME SEVERE BEFORE IT MOVES EAST OF
PRATT AND BARBER COUNTY. AT THIS TIME THE MAIN HAZARD LATE TODAY
WILL BE 2 INCH HAIL AND STRONG GUSTY WINDS.
FURTHER WEST CLEAR SKIES, WARM TEMPERATURES, AND DEWPOINTS IN THE
30S HAVE RESULT IN RELATIVE HUMIDITY VALUES FALLING BACK INTO THE
TEENS AT 00F 18Z. GIVEN THAT THE CLEARING TREND CURRENTLY
OCCURRING WILL CONTINUE, BASED ON SATELLITE LOOP, AND THE 850MB
MIX DOWN TEMPERATURES AT 00Z THURSDAY IT APPEARS THAT CRITICAL
FIRE WEATHER CONDITIONS WILL STILL EXIST LATE TODAY. AS A RESULT
WILL LEAVE THE CURRENT RED FLAG WARNING GOING FOR PORTIONS OF
SOUTHWEST KANSAS.
FOR THE REMAINDER OF THE OVERNIGHT PERIOD...THE SURFACE BOUNDARY,
WHICH WAS LOCATED OVER SOUTHWEST KANSAS LATE THIS AFTERNOON/EARLY
EVENING, WILL MOVE SOUTH AS AN UPPER LEVEL TROUGH CROSSES THE
CENTRAL HIGH PLAINS. BASED ON THE SURFACE DEW POINTS EXPECTED
EARLY THURSDAY MORNING, SOME MID OR HIGH CLOUDS PRECEDING THE
UPPER LEVEL TROUGH, AND A DEVELOPING NORTHWESTERLY FLOW THE
PREVIOUS FORECAST STILL APPEARS ON TRACK WITH LOWS BOTTOMING OUT
MAINLY IN THE 40S ACROSS WESTERN KANSAS. LOWS IN THE 50 TO NEAR 55
DEGREE RANGE WILL BE LIKELY ACROSS SOUTH CENTRAL KANSAS.
THE UPPER LEVEL TROUGH WILL CROSS WESTERN KANSAS EARLY THURSDAY
MORNING AS A SURFACE HIGHS BEGINS TO BUILD INTO NORTHWESTERN
KANSAS/NORTHEAST COLORADO. OVER WESTERN KANSAS GUSTY NORTHWEST
WINDS AT 20 TO NEAR 30 MPH ARE EXPECTED BY THE EARLY AFTERNOON
BASED ON 0-1KM WINDS RANGING FROM 25 TO NEAR 35 KNOTS, AND THE
MEAN MIXED LAYER WINDS AT 18Z AND 21Z RANGING FROM 30 TO 35KNOTS.
BASED ON THE MIXING POTENTIAL THURSDAY AFTERNOON FROM THE BUFR
NAM, AND THE 850MB TEMPERATURES AT 00Z FRIDAY WILL TREND TOWARDS
THE WARMER GUIDANCE ACROSS WESTERN KANSAS.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 256 AM CDT WED APR 8 2015
THE UPPER LEVEL SHORTWAVE WILL MOVE OUT OF THE HIGH PLAINS
THURSDAY WITH A WEAK UPPER LEVEL RIDGE BUILDING OVER THE ROCKIES
AND PLAINS THURSDAY NIGHT THROUGH FRIDAY NIGHT. CLOUDS ARE
EXPECTED TO DECREASE IN COVERAGE OVER NORTHERN KANSAS THURSDAY
WITH MOSTLY CLEAR SKIES ANTICIPATED THERE AND ELSEWHERE THROUGH
FRIDAY. TOWARDS THE SURFACE, A DOME OF HIGH PRESSURE WILL BUILD
INTO THE AREA BEHIND THE PREVIOUS SYSTEM LEADING TO NORTH TO
NORTHWEST WINDS ACROSS WESTERN KANSAS. THE CENTER OF HIGH PRESSURE
MOVES EAST OF THE AREA BY FRIDAY SHIFTING WINDS BACK TO MORE OF A
SOUTHERLY DIRECTION. SOUTHERLY WINDS CONTINUE FRIDAY NIGHT WITH A
SLIGHT INCREASE IN HIGH CLOUDS AS THE NEXT SYSTEM, ELABORATED
ABOUT BELOW, APPROACHES.
ATTENTION THEN FOCUSES ON THE WEEKEND AS AN UPPER LEVEL SHORTWAVE
INTENSIFIES ABOVE THE DESERT SOUTHWEST THEN TRACKS EASTWARD ACROSS
THE SOUTHERN ROCKIES BEFORE CURLING NORTHWARD INTO THE PLAINS.
TOWARDS THE SURFACE, THE AFOREMENTIONED DOME OF HIGH PRESSURE WILL
CONTINUE TO SHIFT EASTWARD AS THIS FEATURE APPROACHES ALLOWING
GULF MOISTURE TO BE PUSHED NORTH INTO THE PLAINS. A FEW
THUNDERSTORMS WILL BE POSSIBLE OVER THE WEEKEND WITH INCREASED
CLOUD COVER. A QUIET PATTERN THEN RETURNS EARLY NEXT WEEK AS AN
UPPER LEVEL RIDGE BUILDS ACROSS THE SOUTHWEST UNITED STATES.
AS FOR TEMPERATURES, HIGHS WILL GENERALLY BE IN THE 60S THURSDAY
AND FRIDAY WITH LOWS IN THE 30S THURSDAY NIGHT AND IN THE MID 40S
FRIDAY NIGHT. HIGHS THEN REBOUND INTO THE 70S SATURDAY WITH CLOSER
TO 80 DEGREES EXPECTED ON SUNDAY. LOWS DURING THIS TIME FRAME WILL
GENERALLY RANGE FROM THE MID 40S TO MID 50S. HIGHS DURING THE
BEGINNING OF NEXT WEEK LOOK TO BE IN THE 70S WITH LOWS CONTINUING
TO RANGE FROM THE MID 40S TO MID 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1215 PM CDT WED APR 8 2015
STATUS AND FOG WILL ERODE THIS AFTERNOON AS A SURFACE BOUNDARY
BEGINS TO SLOWLY MOVE NORTH ACROSS SOUTHWEST KANSAS. AT THIS TIME
BASED ON THE LATEST TRENDS FROM THE HRRR AND RAP WILL GRADUALLY
IMPROVE CEILING WITH VFR CONDITIONS DEVELOPING BETWEEN 20Z AND
22Z AT DDC AND GCK. HYS WILL IMPROVE TO MVFR. VFR CONDITIONS AT
HYS IS EXPECTED TO DEVELOP TOWARDS 00Z THURSDAY. THE PREVAILING
WIND THIS AFTERNOON NORTH OF THIS FRONT WILL BE NORTHERLY AT 10
KNOTS OR LESS. NORTHWEST WINDS WILL DEVELOP OVERNIGHT AS A COLD
FRONT CROSSES WESTERN KANSAS. THE NORTHWESTERLY WINDS WILL
INCREASE BY LATE MORNING THURSDAY AS STRONGER BOUNDARY LAYER WINDS
MIXED DOWN TO THE SURFACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 46 66 35 67 / 10 10 0 0
GCK 42 64 34 68 / 10 10 0 0
EHA 42 65 35 68 / 10 10 0 0
LBL 44 67 36 68 / 0 10 0 0
HYS 45 62 34 67 / 20 10 0 0
P28 53 72 38 69 / 10 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM CDT /8 PM MDT/ THIS EVENING FOR
KSZ061-062-074>076-084>088.
&&
$$
SHORT TERM...BURGERT
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS WICHITA KS
1243 PM CDT WED APR 8 2015
.MESOSCALE DISCUSSION...
ISSUED AT 1245 PM CDT WED APR 8 2015
FRONT NOW DRIFTING SOUTHEAST AND IS LOCATED FROM KK68-KWDG.
INSPECTION OGT HE WSR-88D DATA SHOWS THE FRONT FROM ROSALIA-
MULVANE-BLUFF CITY. INFLECTION POINT SEEMS TO HAVE DEVELOPED NEAR
MULVANE.
FIRST ROUND OF CONVECTION NOW MOVING ACROSS NORTHERN OKLAHOMA AND
INCREASING IN INTENSITY. THE LATEST HRRR/RAP RUNS SHOW THIS WELL
AND BRING CONVECTION NORTHEAST FROM THAT LOCATION. THE MAIN THREAT
CONTINUES TO BE LARGE HAIL AND WIND DAMAGE. THE LARGE HAIL
PARAMETER DOES SUGGEST SIGNIFICANT HAIL POTENTIAL.
THE RAP CONTINUES TO SHOW A RETROGRADING BOUNDARY WITH A
SIGNIFICANT INCREASE OF LOW LEVEL CAPE. THIS IN CONJUNCTION WITH
THE INCREASE IN SHEAR FROM THE INCOMING DISTURBANCE COUPLED WITH
THE LOW LEVEL JET WILL PRODUCE A SCENARIO VERY FAVORABLE FOR
TORNADIC SUPERCELLS.
WHAT HAS BEEN CONSISTENT HAS BEEN THE CONTINUED FOCUS ON AN AREA
THAT INCLUDES COWLEY...SUMNER...AND SOUTHERN BUTLER COUNTIES WHERE
THESE SIGNIFICANT INGREDIENTS ALL COME TOGETHER. THIS IS ONLY NWP
GUIDANCE...BUT THE CONSISTENCY HAS REMAINED AND IS WORTH
MENTIONING.
MOREOVER...THE RAP CONTINUES TO SHOW A HIGH LIKELIHOOD OF
TORNADOES CONTINUING AFTER DARK. PRETTY GOOD CONFIDENCE IN THIS
SCENARIO.
KRC
&&
.SYNOPSIS...
ISSUED AT 332 AM CDT WED APR 8 2015
WATER VAPOR IMAGERY SHOWS A STRONG SHORTWAVE TRACKING OVER THE
CENTRAL GREAT BASIN. AT THE SURFACE...LOW PRESSURE IS SITUATED
OVER SE CO WITH THE SYNOPTIC FRONT STRETCHING FROM JUST NORTH OF
KGAG TO BETWEEN KCNU AND KPPF. MEANWHILE...A LOSE DRYLINE EXTENDS
ACROSS THE OK PANHANDLE AND INTO WEST TX.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
ELEVATED STORMS DEVELOPED A COUPLE HOURS AGO OVER THE FLINT HILLS
IN RESPONSE TO A RAPID INCREASE IN MOISTURE TRANSPORT IN THE
850-700MB LAYER. THIS ACTIVITY SHOULD FOR THE MOST PART STAY
NORTHEAST OF THE FORECAST AREA.
SIGNIFICANT SEVERE STORMS STILL LOOK LIKELY THIS AFTERNOON AND
EVENING. CURRENTLY HAVE A LEAN TO THE RAP13 DUE TO ITS PERFORMANCE
WITH THE CONVECTION THAT OCCURRED OVER THE LAST SEVERAL HOURS OVER
SE KS. IN ADDITION...IT SEEMS TO BE DOING A DECENT JOB CAPTURING
THE CURRENT ELEVATED CONVECTION. THE GFS LIFTS THE WARM FRONT
MUCH FURTHER NORTH COMPARED TO THE NAM AND RAP WITH THE FRONT
ALONG I-70. MEANWHILE THE RAP AND NAM LIFT THE FRONT TO JUST NORTH
OF KICT TO SOUTH OF KSLN.
CURRENT THINKING IS THAT THE TRIPLE POINT BY LATE AFTERNOON WILL
BE SITUATED JUST SOUTHWEST OF THE FORECAST AREA NEAR OR JUST NORTH
OF KGAG WITH THE SYNOPTIC FRONT EXTENDING TO THE NORTHEAST NEAR
KICT AND THEN TO NEAR KEMP. WATER VAPOR IMAGERY SHOWS A LEAD
IMPULSE/JET MAX OVER NORTHERN BAJA. EXPECTING STORMS TO DEVELOP
NEAR THE TRIPLE POINT AS THIS FEATURE MOVES OUT OF THE SOUTHERN
HIGH PLAINS. ADDITIONAL DEVELOPMENT CAN THEN BE EXPECTED NORTHEAST
ALONG THE SYNOPTIC FRONT. IT SEEMS WITH EACH MODEL RUN THE DEEP
LAYER SHEAR HAS INCREASED SLIGHTLY AND THE 00Z RUNS WERE NO
EXCEPTION...WITH AROUND 50KTS OF 0-6KM SHEAR AND 65-80KTS OF
0-8KM SHEAR OVER SOUTH CENTRAL KS. THESE SHEAR VALUES WILL COMBINE
WITH 2000-3000J/KG OF CAPE TO ALLOW ANY STORM THAT DEVELOPS TO
QUICKLY BECOME SEVERE. THE SCARY PART IS THAT WITH THE
RETREATING DRYLINE AFTER 00Z...THE ENVIRONMENT ACTUALLY BECOMES
MORE FAVORABLE AFTER DARK AS WINDS BACK AND THE LOW LEVEL JET GETS
GOING. SO NOT OUT OF THE QUESTION TO GET A TORNADO AFTER DARK OVER
SOUTH CENTRAL KS. THE BEST TORNADO POTENTIAL TONIGHT LOOKS TO BE
SOUTH OF HIGHWAY 50 AND WEST OF HIGHWAY 99. IF THE NAM AND RAP13
VERIFIES...SEVERE STORMS OVER CENTRAL KS WOULD BE LESS LIKELY.
BY 12Z THU...THE SHORTWAVE WILL BE TRACKING ACROSS NORTHERN
KS/NEBRASKA WITH THE SYNOPTIC FRONT CATCHING UP TO THE DRYLINE AND
SURGING EAST. WHILE THERE MAYBE SOME REMNANT STORMS OVER SE KS
AROUND SUNRISE...THE BULK OF THE ACTIVITY AFTER 15Z THU WILL BE
EAST OF THE FORECAST AREA. IT NOW LOOKS LIKE THE BETTER CHANCES
FOR PRECIP ON THE BACKSIDE OF THIS SYSTEM SHOULD STAY NORTH OF THE
FORECAST AREA THU.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
A LARGE AREA OF HIGH PRESSURE WILL ENCOMPASS THE PLAINS FOR FRI
WITH TEMPS FINALLY GETTING BACK TO SEASONAL VALUES. BOTH THE GFS
AND ECMWF BRING A SOUTHERN STREAM SYSTEM OUT OF THE BAJA REGION
AND INTO WEST TX BY SUN EVENING. WARM ADVECTION AHEAD OF THIS
SYSTEM MAY BRING SOME SCATTERED SHOWERS AND STORMS SAT BUT THE
BETTER PRECIP CHANCES LOOK TO ARRIVE SUN NIGHT AND CONTINUE
THROUGH MON WHEN THE IMPULSE LIFTS ACROSS THE PLAINS. THE GFS HAS
THIS FEATURE QUITE A BIT FURTHER WEST COMPARED TO THE ECMWF WHICH
RESULTS IN THE ECMWF BEING THE WETTER SOLUTION.
LAWSON
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1208 PM CDT WED APR 8 2015
CONVECTION NOW DEVELOPING OVER OKLAHOMA WILL MOVE NORTHEAST INTO
THE AIRSPACE AND CONTINUE WITH SEVERAL ROUNDS THROUGH 6Z. THIS
WILL AFFECT ALL AIRPORTS AND FIELDS ALONG AND SOUTHEAST OF KSLN-
KVNX. THESE STORMS WILL BE SEVERE AND SHOULD BE AVOIDED.
FOG...WHICH CONTINUES TO AFFECT KHUT...KRSL...KSLN HAS BEEN SLOW
TO BURN OFF. THINK IT SHOULD BE GONE BY 21Z. VFR CONDITIONS SHOULD
PERSIST THROUGH 03Z...WITH FOG REDEVELOPMENT THERE POSSIBLE
THROUGH 12Z.
THE COLD FRONT WILL CLEAR THE AREA BY 14Z.
&&
.FIRE WEATHER...
ISSUED AT 332 AM CDT WED APR 8 2015
MAIN FIRE WEATHER CONCERNS LOOK TO ON THURSDAY.
EVEN WITH PLENTY OF LOW LEVEL MOISTURE...VERY HIGH FIRE DANGER
WILL BE IN PLACE OVER SOUTH CENTRAL AND SE KS DUE TO GUSTY SOUTH
WINDS. HOWEVER...THE CRITICAL FIRE WEATHER DAY LOOKS TO BE THU.
THIS IS WHEN STRONG NW WINDS WILL BE IN PLACE BY THE AFTERNOON
HOURS ALONG WITH RH`S IN THE 35-45% RANGE. WIND SPEEDS THU
AFTERNOON WILL BE IN THE 20-30 MPH RANGE WITH HIGHER GUSTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 83 56 71 38 / 30 30 10 0
HUTCHINSON 75 52 67 37 / 30 20 10 0
NEWTON 77 54 67 38 / 40 30 10 0
ELDORADO 83 60 69 40 / 40 40 10 10
WINFIELD-KWLD 85 61 72 41 / 40 30 10 0
RUSSELL 64 46 63 35 / 20 20 10 10
GREAT BEND 69 46 64 35 / 20 10 10 0
SALINA 67 50 65 35 / 30 30 20 10
MCPHERSON 70 51 66 36 / 30 30 10 10
COFFEYVILLE 82 65 76 43 / 40 40 30 10
CHANUTE 78 64 73 41 / 40 50 30 10
IOLA 78 63 72 40 / 40 50 30 10
PARSONS-KPPF 81 64 74 42 / 40 50 30 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1217 PM CDT WED APR 8 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT WED APR 8 2015
MAIN CONCERNS WITH THIS PART OF THE FORECAST CENTER AROUND DENSE
FOG POTENTIAL THIS MORNING AND THEN RED FLAG CONDITIONS OVER FAR
SOUTHWEST KANSAS AND SEVERE STORM POTENTIAL OVER SOUTH CENTRAL
KANSAS THIS AFTERNOON AND EARLY EVENING.
A STATIONARY FRONT CONTINUED TO EXTEND FROM THE FRONT RANGE OF
CENTRAL COLORADO ACROSS THE FAR SOUTHWEST CORNER OF KANSAS INTO
NORTHERN OKLAHOMA AND BACK NORTHEAST ACROSS THE SOUTHEAST PART OF
KANSAS INTO MISSOURI. A SURGE OF EASTERLY UPSLOPE FLOW TO THE
NORTH OF THE FRONT HAS RESULTED IN STRATUS SURGING BACK SOUTH
ACROSS WESTERN KANSAS OVERNIGHT. WIDESPREAD LIGHT FOG WAS ALSO
DEVELOPING ALONG WITH SOME PATCHY DRIZZLE OVER NORTHWEST AND WEST
CENTRAL KANSAS.
MODEL SOUNDINGS SHOW THE SATURATED BOUNDARY LAYER THE DEEPEST OVER
CENTRAL KANSAS ALONG I-70 WITH THE LAYER BECOMING MORE SHALLOW OUT
NEAR THE COLORADO AND OKLAHOMA BORDERS. WILL KEEP A MENTION OF FOG
AND DRIZZLE OVER MUCH OF THE AREA GENERALLY NORTH OF HIGHWAY 50
EARLY THIS MORNING ALTHOUGH THE BEST POTENTIAL FOR ANY DRIZZLE
WILL BE ALONG I-70. SHORT TERM MESOSCALE MODELS HAVE BEEN TRENDING
TOWARD AN AREA OF DENSE FOG DEVELOPING OVER FAR SOUTHWEST KANSAS
INTO EAST CENTRAL COLORADO EARLY THIS MORNING. WHILE A FEW POCKETS
OF DENSE FOG HAD DEVELOPED EARLIER IN NORTHWEST KANSAS, IT DOES
NOT APPEAR TO BE A SOLID TREND IN THAT DIRECTION YET. FOR NOW WILL
HOLD OFF ON ANY DENSE FOG HEADLINES BUT WILL CONTINUE TO SHOW FOG
WITH 1/2 MILE VISIBILITY REDUCTIONS IN THE FAR SOUTHWEST.
CONDITIONS WILL BEGIN TO IMPROVE AFTER SUNRISE WITH THE FOG AND
STRATUS DISSIPATING FROM SOUTH TO NORTH DURING THE DAY. HAYS WILL
BE THE LAST TO CLEAR OUT WITH SOME SUN POSSIBLE BY LATE AFTERNOON.
THE MODELS SHOW THE FRONT LIFTING NORTHWARD ACROSS FAR SOUTHWEST
KANSAS THIS AFTERNOON WITH WARMER AND DRIER AIR MOVING IN. THERE
WILL BE A FAIRLY LARGE TEMPERATURE GRADIENT ACROSS THE AREA WITH
HAYS ONLY REACHING AROUND 60 OR SO WHILE IN THE SOUTHWEST CORNER,
ELKHART AND LIBERAL SHOULD CLIMB INTO THE MID 80S.
FARTHER EAST, THE FRONT SHOULD LIFT NORTHWARD TO NEAR MEDICINE
LODGE THIS AFTERNOON WHILE A DRYLINE TRAILS FROM THAT AREA
SOUTHWARD INTO OKLAHOMA. MODEL SOUNDINGS AROUND MEDICINE LODGE
SHOW LAPSE RATES STEEPENING AS THE LOWER ATMOSPHERE MIXES OUT THIS
AFTERNOON. IN ADDITION, FAIRLY STRONG 0-6 KM SHEAR ON THE ORDER OF
50-60 KNOTS WILL OVERSPREAD THE REGION. A FEW THUNDERSTORMS COULD
DEVELOP ALONG THE DRYLINE/FRONT INTERSECTION AS UPPER LEVEL LIFT
INCREASES WITH A 500 MILLIBAR SHORTWAVE APPROACHING THE REGION.
ANY STORMS THAT DEVELOP WILL BE MOVING OFF FAIRLY RAPIDLY TO THE
EAST AND THE THREAT FOR SEVERE WEATHER WILL LIKELY ONLY BE DURING
THE LATE AFTERNOON AND EARLY EVENING.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 256 AM CDT WED APR 8 2015
THE UPPER LEVEL SHORTWAVE WILL MOVE OUT OF THE HIGH PLAINS
THURSDAY WITH A WEAK UPPER LEVEL RIDGE BUILDING OVER THE ROCKIES
AND PLAINS THURSDAY NIGHT THROUGH FRIDAY NIGHT. CLOUDS ARE
EXPECTED TO DECREASE IN COVERAGE OVER NORTHERN KANSAS THURSDAY
WITH MOSTLY CLEAR SKIES ANTICIPATED THERE AND ELSEWHERE THROUGH
FRIDAY. TOWARDS THE SURFACE, A DOME OF HIGH PRESSURE WILL BUILD
INTO THE AREA BEHIND THE PREVIOUS SYSTEM LEADING TO NORTH TO
NORTHWEST WINDS ACROSS WESTERN KANSAS. THE CENTER OF HIGH PRESSURE
MOVES EAST OF THE AREA BY FRIDAY SHIFTING WINDS BACK TO MORE OF A
SOUTHERLY DIRECTION. SOUTHERLY WINDS CONTINUE FRIDAY NIGHT WITH A
SLIGHT INCREASE IN HIGH CLOUDS AS THE NEXT SYSTEM, ELABORATED
ABOUT BELOW, APPROACHES.
ATTENTION THEN FOCUSES ON THE WEEKEND AS AN UPPER LEVEL SHORTWAVE
INTENSIFIES ABOVE THE DESERT SOUTHWEST THEN TRACKS EASTWARD ACROSS
THE SOUTHERN ROCKIES BEFORE CURLING NORTHWARD INTO THE PLAINS.
TOWARDS THE SURFACE, THE AFOREMENTIONED DOME OF HIGH PRESSURE WILL
CONTINUE TO SHIFT EASTWARD AS THIS FEATURE APPROACHES ALLOWING
GULF MOISTURE TO BE PUSHED NORTH INTO THE PLAINS. A FEW
THUNDERSTORMS WILL BE POSSIBLE OVER THE WEEKEND WITH INCREASED
CLOUD COVER. A QUIET PATTERN THEN RETURNS EARLY NEXT WEEK AS AN
UPPER LEVEL RIDGE BUILDS ACROSS THE SOUTHWEST UNITED STATES.
AS FOR TEMPERATURES, HIGHS WILL GENERALLY BE IN THE 60S THURSDAY
AND FRIDAY WITH LOWS IN THE 30S THURSDAY NIGHT AND IN THE MID 40S
FRIDAY NIGHT. HIGHS THEN REBOUND INTO THE 70S SATURDAY WITH CLOSER
TO 80 DEGREES EXPECTED ON SUNDAY. LOWS DURING THIS TIME FRAME WILL
GENERALLY RANGE FROM THE MID 40S TO MID 50S. HIGHS DURING THE
BEGINNING OF NEXT WEEK LOOK TO BE IN THE 70S WITH LOWS CONTINUING
TO RANGE FROM THE MID 40S TO MID 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1215 PM CDT WED APR 8 2015
STATUS AND FOG WILL ERODE THIS AFTERNOON AS A SURFACE BOUNDARY
BEGINS TO SLOWLY MOVE NORTH ACROSS SOUTHWEST KANSAS. AT THIS TIME
BASED ON THE LATEST TRENDS FROM THE HRRR AND RAP WILL GRADUALLY
IMPROVE CEILING WITH VFR CONDITIONS DEVELOPING BETWEEN 20Z AND
22Z AT DDC AND GCK. HYS WILL IMPROVE TO MVFR. VFR CONDITIONS AT
HYS IS EXPECTED TO DEVELOP TOWARDS 00Z THURSDAY. THE PREVAILING
WIND THIS AFTERNOON NORTH OF THIS FRONT WILL BE NORTHERLY AT 10
KNOTS OR LESS. NORTHWEST WINDS WILL DEVELOP OVERNIGHT AS A COLD
FRONT CROSSES WESTERN KANSAS. THE NORTHWESTERLY WINDS WILL
INCREASE BY LATE MORNING THURSDAY AS STRONGER BOUNDARY LAYER WINDS
MIXED DOWN TO THE SURFACE.
&&
.FIRE WEATHER...
ISSUED AT 400 AM CDT WED APR 8 2015
RED FLAG CONDITIONS WILL REDEVELOP OVER FAR SOUTHWEST KANSAS AGAIN
THIS AFTERNOON AS A FRONTAL BOUNDARY ALONG THE OKLAHOMA BORDER
LIFTS TO THE NORTH, ALLOWING VERY WARM AND DRY AIR BACK INTO THE
AREA. THE FRONT WILL BE SLOW TO MOVE SO THE CRITICAL AREA WILL BE
FAIRLY SMALL IN THE SOUTHWEST CORNER OF THE STATE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 79 46 66 35 / 10 10 10 0
GCK 77 42 64 34 / 10 10 10 0
EHA 83 42 65 35 / 0 10 10 0
LBL 86 44 67 36 / 0 0 10 0
HYS 60 45 62 34 / 10 20 10 0
P28 82 53 72 38 / 20 10 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM CDT /8 PM MDT/ THIS EVENING FOR
KSZ061-062-074>076-084>088.
&&
$$
UPDATE...JTL
SHORT TERM...GERARD LONG
AVIATION...BURGERT
FIRE WEATHER...GERARD
AREA FORECAST DISCUSSION
NWS WICHITA KS
1207 PM CDT WED APR 8 2015
.MESOSCALE DISCUSSION...
ISSUED AT 1037 AM CDT WED APR 8 2015
LOOKS LIKE THE SCENARIO MAY BE STARTING TO SHOW ITSELF. RADAR DATA
SHOWING SOME LIGHT RETURNS OVER OKLAHOMA. THIS MATCHES WELL WITH
THE HRRR/RAP RUNS...WHICH HAVE BEEN SUGGESTING TWO ROUNDS OF
STORMS.
THE MOST LIKELY SCENARIO RIGHT NOW LOOKS LIKE THE WEAK RETURNS
WILL DEVELOP INTO ELEVATED STORMS ACROSS OKLAHOMA. THESE ARE
EXPECTED TO MOVE NORTHEAST INTO SOUTH-CENTRAL KANSAS AROUND 19Z
AND MOVE THROUGH SOUTHEAST KANSAS EAST OF THE TURNPIKE. AS
STATED...THESE WILL MORE THAN LIKELY BE ELEVATED WITH A VERY LARGE
HAIL AND WIND THREAT. IF THE STORMS CAN GET SURFACE BASED...THEN
IT SEEMS THAT WE COULD GET A TORNADO...BUT THAT REMAINS UNCERTAIN.
THE SECOND ROUND OCCURS AROUND 00Z WHERE THE DRYLINE RETREATS AND
SHEAR INCREASES AS A RESULT OF THE LOW LEVEL JET AND UPPER LEVEL
DISTURBANCE COUPLING AND MOVING THROUGH. THIS IS THE SIGNIFICANT
TORNADO AREA...SOUTH-CENTRAL KANSAS.
KRC
.SYNOPSIS...
ISSUED AT 332 AM CDT WED APR 8 2015
WATER VAPOR IMAGERY SHOWS A STRONG SHORTWAVE TRACKING OVER THE
CENTRAL GREAT BASIN. AT THE SURFACE...LOW PRESSURE IS SITUATED
OVER SE CO WITH THE SYNOPTIC FRONT STRETCHING FROM JUST NORTH OF
KGAG TO BETWEEN KCNU AND KPPF. MEANWHILE...A LOSE DRYLINE EXTENDS
ACROSS THE OK PANHANDLE AND INTO WEST TX.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
ELEVATED STORMS DEVELOPED A COUPLE HOURS AGO OVER THE FLINT HILLS
IN RESPONSE TO A RAPID INCREASE IN MOISTURE TRANSPORT IN THE
850-700MB LAYER. THIS ACTIVITY SHOULD FOR THE MOST PART STAY
NORTHEAST OF THE FORECAST AREA.
SIGNIFICANT SEVERE STORMS STILL LOOK LIKELY THIS AFTERNOON AND
EVENING. CURRENTLY HAVE A LEAN TO THE RAP13 DUE TO ITS PERFORMANCE
WITH THE CONVECTION THAT OCCURRED OVER THE LAST SEVERAL HOURS OVER
SE KS. IN ADDITION...IT SEEMS TO BE DOING A DECENT JOB CAPTURING
THE CURRENT ELEVATED CONVECTION. THE GFS LIFTS THE WARM FRONT
MUCH FURTHER NORTH COMPARED TO THE NAM AND RAP WITH THE FRONT
ALONG I-70. MEANWHILE THE RAP AND NAM LIFT THE FRONT TO JUST NORTH
OF KICT TO SOUTH OF KSLN.
CURRENT THINKING IS THAT THE TRIPLE POINT BY LATE AFTERNOON WILL
BE SITUATED JUST SOUTHWEST OF THE FORECAST AREA NEAR OR JUST NORTH
OF KGAG WITH THE SYNOPTIC FRONT EXTENDING TO THE NORTHEAST NEAR
KICT AND THEN TO NEAR KEMP. WATER VAPOR IMAGERY SHOWS A LEAD
IMPULSE/JET MAX OVER NORTHERN BAJA. EXPECTING STORMS TO DEVELOP
NEAR THE TRIPLE POINT AS THIS FEATURE MOVES OUT OF THE SOUTHERN
HIGH PLAINS. ADDITIONAL DEVELOPMENT CAN THEN BE EXPECTED NORTHEAST
ALONG THE SYNOPTIC FRONT. IT SEEMS WITH EACH MODEL RUN THE DEEP
LAYER SHEAR HAS INCREASED SLIGHTLY AND THE 00Z RUNS WERE NO
EXCEPTION...WITH AROUND 50KTS OF 0-6KM SHEAR AND 65-80KTS OF
0-8KM SHEAR OVER SOUTH CENTRAL KS. THESE SHEAR VALUES WILL COMBINE
WITH 2000-3000J/KG OF CAPE TO ALLOW ANY STORM THAT DEVELOPS TO
QUICKLY BECOME SEVERE. THE SCARY PART IS THAT WITH THE
RETREATING DRYLINE AFTER 00Z...THE ENVIRONMENT ACTUALLY BECOMES
MORE FAVORABLE AFTER DARK AS WINDS BACK AND THE LOW LEVEL JET GETS
GOING. SO NOT OUT OF THE QUESTION TO GET A TORNADO AFTER DARK OVER
SOUTH CENTRAL KS. THE BEST TORNADO POTENTIAL TONIGHT LOOKS TO BE
SOUTH OF HIGHWAY 50 AND WEST OF HIGHWAY 99. IF THE NAM AND RAP13
VERIFIES...SEVERE STORMS OVER CENTRAL KS WOULD BE LESS LIKELY.
BY 12Z THU...THE SHORTWAVE WILL BE TRACKING ACROSS NORTHERN
KS/NEBRASKA WITH THE SYNOPTIC FRONT CATCHING UP TO THE DRYLINE AND
SURGING EAST. WHILE THERE MAYBE SOME REMNANT STORMS OVER SE KS
AROUND SUNRISE...THE BULK OF THE ACTIVITY AFTER 15Z THU WILL BE
EAST OF THE FORECAST AREA. IT NOW LOOKS LIKE THE BETTER CHANCES
FOR PRECIP ON THE BACKSIDE OF THIS SYSTEM SHOULD STAY NORTH OF THE
FORECAST AREA THU.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 332 AM CDT WED APR 8 2015
A LARGE AREA OF HIGH PRESSURE WILL ENCOMPASS THE PLAINS FOR FRI
WITH TEMPS FINALLY GETTING BACK TO SEASONAL VALUES. BOTH THE GFS
AND ECMWF BRING A SOUTHERN STREAM SYSTEM OUT OF THE BAJA REGION
AND INTO WEST TX BY SUN EVENING. WARM ADVECTION AHEAD OF THIS
SYSTEM MAY BRING SOME SCATTERED SHOWERS AND STORMS SAT BUT THE
BETTER PRECIP CHANCES LOOK TO ARRIVE SUN NIGHT AND CONTINUE
THROUGH MON WHEN THE IMPULSE LIFTS ACROSS THE PLAINS. THE GFS HAS
THIS FEATURE QUITE A BIT FURTHER WEST COMPARED TO THE ECMWF WHICH
RESULTS IN THE ECMWF BEING THE WETTER SOLUTION.
LAWSON
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1208 PM CDT WED APR 8 2015
CONVECTION NOW DEVELOPING OVER OKLAHOMA WILL MOVE NORTHEAST INTO
THE AIRSPACE AND CONTINUE WITH SEVERAL ROUNDS THROUGH 6Z. THIS
WILL AFFECT ALL AIRPORTS AND FIELDS ALONG AND SOUTHEAST OF KSLN-
KVNX. THESE STORMS WILL BE SEVERE AND SHOULD BE AVOIDED.
FOG...WHICH CONTINUES TO AFFECT KHUT...KRSL...KSLN HAS BEEN SLOW
TO BURN OFF. THINK IT SHOULD BE GONE BY 21Z. VFR CONDITIONS SHOULD
PERSIST THROUGH 03Z...WITH FOG REDEVELOPMENT THERE POSSIBLE
THROUGH 12Z.
THE COLD FRONT WILL CLEAR THE AREA BY 14Z.
KRC
&&
.FIRE WEATHER...
ISSUED AT 332 AM CDT WED APR 8 2015
MAIN FIRE WEATHER CONCERNS LOOK TO ON THURSDAY.
EVEN WITH PLENTY OF LOW LEVEL MOISTURE...VERY HIGH FIRE DANGER
WILL BE IN PLACE OVER SOUTH CENTRAL AND SE KS DUE TO GUSTY SOUTH
WINDS. HOWEVER...THE CRITICAL FIRE WEATHER DAY LOOKS TO BE THU.
THIS IS WHEN STRONG NW WINDS WILL BE IN PLACE BY THE AFTERNOON
HOURS ALONG WITH RH`S IN THE 35-45% RANGE. WIND SPEEDS THU
AFTERNOON WILL BE IN THE 20-30 MPH RANGE WITH HIGHER GUSTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 83 56 71 38 / 30 30 10 0
HUTCHINSON 75 52 67 37 / 30 20 10 0
NEWTON 77 54 67 38 / 40 30 10 0
ELDORADO 83 60 69 40 / 40 40 10 10
WINFIELD-KWLD 85 61 72 41 / 40 30 10 0
RUSSELL 64 46 63 35 / 20 20 10 10
GREAT BEND 69 46 64 35 / 20 10 10 0
SALINA 67 50 65 35 / 30 30 20 10
MCPHERSON 70 51 66 36 / 30 30 10 10
COFFEYVILLE 82 65 76 43 / 40 40 30 10
CHANUTE 78 64 73 41 / 40 50 30 10
IOLA 78 63 72 40 / 40 50 30 10
PARSONS-KPPF 81 64 74 42 / 40 50 30 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
649 PM EDT Wed Apr 8 2015
...Updated Aviation Discussion...
...Forecast Update...
Issued at 525 PM EDT Wed Apr 8 2015
The Severe Thunderstorm Watch has been converted to a Tornado Watch
across southern IN and has been extended until 10 PM EDT. Backed low
level flow and organized storms along the boundary have led to some
cells with significant rotation. Winds, hail, and isolated tornadoes
will be possible. South of the watch area, hail will continue to be
possible over the next couple of hours. This activity should then
diminish later this evening.
.SHORT TERM (Now through Thursday Night)...
Issued at 308 PM EDT Wed Apr 8 2015
...More Strong Storms Possible This Evening and Tomorrow...
Multiple boundaries have set up across the region this afternoon.
SPC mesoanalysis shows all the CIN from earlier in the day has
eroded and we have become moderately unstable with 2500-3500 J/kg CAPE.
A Severe Thunderstorm Watch has been issued for southern Indiana for
this afternoon and early evening. However, given the multiple
boundaries and possibility for strong storms elsewhere around the
forecast area, extensions to the Watch are not out of the question
this afternoon. Large hail and damaging winds will be the main
threats this afternoon, though a tornado or two cannot be ruled out
completely. The other concern for tonight will be the possibility of
training thunderstorms, particularly across southern IN and north
central KY. The latest runs of the HRRR have been suggesting this.
Given that flash flood values are under an inch an hour and storms
may train in this area, have gone ahead and issued a Flash Flood
Watch starting late this afternoon and continuing through tomorrow
night.
There should be a relative lull in the storms for much of the
overnight period as any storms that develop this afternoon will move
out late this evening. Think another complex associated with a weak
upper level wave will move in early tomorrow morning and continue
through the morning hours. Some small hail and gusty winds will be
possible with these storms.
There should be at least a short break in storm coverage tomorrow
afternoon ahead of the more significant chance for severe weather
along and ahead of the cold front tomorrow night. Moisture will pool
ahead of the front with strong southerly winds through the afternoon
tomorrow. Forcing will come from the upper level trough moving in
and an upper level jet. Shear will increase and hodographs exhibit
favorable clockwise curving tomorrow night. A broken line of showers
and thunderstorms looks to develop to our west congeal into a line
as it moves into the forecast area tomorrow evening. Damaging winds
will be the the main threat with the squall line, with a few
embedded tornadoes possible. If any cells do develop ahead of the
main line hail could be a threat as well.
Due to the repeated areas of convection moving across the region,
have kept the Flash Flood Watch in place through tomorrow night.
Repeated rains will only exacerbate or renew flooding problems.
.LONG TERM (Friday through Wednesday)...
Issued at 241 PM EDT Wed Apr 8 2015
Not much has changed in the thinking for the long term period. Due
to the ongoing storms an updated discussion will not be issued this
afternoon. The previous discussion is below.
Previous discussion
-------------------
Cold front should pass through the area during the pre-dawn hours
Friday in our west then sweep across the rest of central Kentucky
during the early morning hours. Westerly flow will bring in a drier
and quieter pattern Friday night.
Plan on a pleasant, sunny and seasonable Saturday with high pressure
over the lower Ohio Valley. Sunday will start off in similar fashion
but as the high quickly moves to the east, southerly return flow
will begin to push another slug of warm, moist air to the region.
Shower chances return Sunday night through Monday as a trough digs
across the central Plains. High-end chance to likely POPs look
reasonable early next week with near normal temperatures.
&&
.AVIATION (00Z TAF Update)...
Updated at 645 PM EDT Wed Apr 8 2015
Scattered thunderstorms will continue across north central KY for
the next few hours. These storms will continue to affect SDF and LEX
off an on. Storms are expected to diminish by 03Z or so with drier
conditions for much of the rest of the night. A few showers may
develop around BWG over the next few hours, but storms are not
expected at this time.
The next complex of storms will begin to move in around 11-12Z.
These will affect all TAF sites tomorrow morning, moving out early
afternoon. Winds will increase tomorrow afternoon as a cold front
begins to approach from the west. South-southwesterly winds will be
sustained up to around 15 knots with gusts of 20-25 knots.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...FLASH FLOOD WATCH through late Thursday night FOR KYZ023>025-
028>043-045>049-053>057-066-067.
IN...FLASH FLOOD WATCH through late Thursday night FOR INZ076>079-083-
084-089>092.
&&
$$
Update.........EER
Short Term.....EER
Long Term......BJS
Aviation.......EER
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
526 PM EDT Wed Apr 8 2015
...Forecast Update...
Issued at 525 PM EDT Wed Apr 8 2015
The Severe Thunderstorm Watch has been converted to a Tornado Watch
across southern IN and has been extended until 10 PM EDT. Backed low
level flow and organized storms along the boundary have led to some
cells with significant rotation. Winds, hail, and isolated tornadoes
will be possible. South of the watch area, hail will continue to be
possible over the next couple of hours. This activity should then
diminish later this evening.
.SHORT TERM (Now through Thursday Night)...
Issued at 308 PM EDT Wed Apr 8 2015
...More Strong Storms Possible This Evening and Tomorrow...
Multiple boundaries have set up across the region this afternoon.
SPC mesoanalysis shows all the CIN from earlier in the day has
eroded and we have become moderately unstable with 2500-3500 J/kg CAPE.
A Severe Thunderstorm Watch has been issued for southern Indiana for
this afternoon and early evening. However, given the multiple
boundaries and possibility for strong storms elsewhere around the
forecast area, extensions to the Watch are not out of the question
this afternoon. Large hail and damaging winds will be the main
threats this afternoon, though a tornado or two cannot be ruled out
completely. The other concern for tonight will be the possibility of
training thunderstorms, particularly across southern IN and north
central KY. The latest runs of the HRRR have been suggesting this.
Given that flash flood values are under an inch an hour and storms
may train in this area, have gone ahead and issued a Flash Flood
Watch starting late this afternoon and continuing through tomorrow
night.
There should be a relative lull in the storms for much of the
overnight period as any storms that develop this afternoon will move
out late this evening. Think another complex associated with a weak
upper level wave will move in early tomorrow morning and continue
through the morning hours. Some small hail and gusty winds will be
possible with these storms.
There should be at least a short break in storm coverage tomorrow
afternoon ahead of the more significant chance for severe weather
along and ahead of the cold front tomorrow night. Moisture will pool
ahead of the front with strong southerly winds through the afternoon
tomorrow. Forcing will come from the upper level trough moving in
and an upper level jet. Shear will increase and hodographs exhibit
favorable clockwise curving tomorrow night. A broken line of showers
and thunderstorms looks to develop to our west congeal into a line
as it moves into the forecast area tomorrow evening. Damaging winds
will be the the main threat with the squall line, with a few
embedded tornadoes possible. If any cells do develop ahead of the
main line hail could be a threat as well.
Due to the repeated areas of convection moving across the region,
have kept the Flash Flood Watch in place through tomorrow night.
Repeated rains will only exacerbate or renew flooding problems.
.LONG TERM (Friday through Wednesday)...
Issued at 241 PM EDT Wed Apr 8 2015
Not much has changed in the thinking for the long term period. Due
to the ongoing storms an updated discussion will not be issued this
afternoon. The previous discussion is below.
Previous discussion
-------------------
Cold front should pass through the area during the pre-dawn hours
Friday in our west then sweep across the rest of central Kentucky
during the early morning hours. Westerly flow will bring in a drier
and quieter pattern Friday night.
Plan on a pleasant, sunny and seasonable Saturday with high pressure
over the lower Ohio Valley. Sunday will start off in similar fashion
but as the high quickly moves to the east, southerly return flow
will begin to push another slug of warm, moist air to the region.
Shower chances return Sunday night through Monday as a trough digs
across the central Plains. High-end chance to likely POPs look
reasonable early next week with near normal temperatures.
&&
.AVIATION (18Z TAF Update)...
Updated at 1248 PM EDT Wed Apr 8 2015
Scattered thunderstorms are still expected to develop this
afternoon, though have pushed back the timing of VCTS in the TAFs
for a couple of hours. There is still a lot of uncertainty in when
and where the storms will develop so have kept the VCTS as opposed
to introducing TSRA at this time. Those with aviation interests
should keep a close eye on the radar this afternoon.
Expect a decrease in coverage of storms this evening with much of
the night remaining dry at the TAF sites. Another complex looks to
move in early tomorrow morning from the west bringing more showers
and thunderstorms. These should move out by early afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...FLASH FLOOD WATCH through late Thursday night FOR KYZ023>025-
028>043-045>049-053>057-066-067.
IN...FLASH FLOOD WATCH through late Thursday night FOR INZ076>079-083-
084-089>092.
&&
$$
Update.........EER
Short Term.....EER
Long Term......BJS
Aviation.......EER
AREA FORECAST DISCUSSION
NWS JACKSON KY
522 PM EDT WED APR 8 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 455 PM EDT WED APR 8 2015
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST. THEY ALL SHOW SOUTHWEST FLOW OVER KENTUCKY
WITH POCKETS OF ENERGY PASSING THROUGH THE REGION EVERY FEW HOURS.
SOME HEIGHT FALLS WILL GET INTO THE MIX ON THURSDAY AS A LARGER
TROUGH SWEETS EAST AND INTO THE UPPER MIDWEST. THE KEY TO THIS
UNSETTLED PATTERN WILL BE THE SMALLER FEATURES THAT THE HIGHER RES
MODELS...SUCH AS THE HRRR/NAM12...HAVE A BETTER CHANCE OF
CATCHING. THAT BEING SAID...THE CONFIDENCE IS SOMEWHAT LOW GIVEN
THE SMALL SCALE FEATURES AT PLAY.
IN TERMS OF SENSIBLE WEATHER IT HAS BEEN QUITE AN ACTIVE DAY ACROSS
EASTERN KENTUCKY SO FAR... WITH THE LAST PORTION OF THE MORNING
CONVECTION NOW PUSHING OUT OF FAR EASTERN KENTUCKY. BUT THE BIG
QUESTION IS...IS HOW THE CONVECTION NOW FORMING IN CENTRAL KENTUCKY
WILL SOLIDIFY INTO A COMPLEX AND MOVE EWD... OR IF ADDITIONAL
CONVECTION WILL FORM IN EASTERN KENTUCKY AND TRAIN. THE LATEST
HRRR INDICATES MULTIPLE AREAS OF CONVECTION FORMING AND MOVING
THROUGH OUR FORECAST AREA INTO TOMORROW MORNING....WHEREAS THE
NAM12 DOESNT SHOW MUCH OF ANYTHING OVERNIGHT TONIGHT. BUT GIVEN
THE CURRENT INSTABILITY PARAMETERS...CURRENT CONVECTION OUT IN
CENTRAL KY... AND THE FACT THAT THE HRRR DID A GOOD JOB AT
CAPTURING THE DAYTIME CONVECTION... HAVE HEDGED TOWARDS THE HRRR
SOLUTION AND INCREASED TO LIKELY POPS IN THE GRIDS THROUGH 03Z.
HAVE ALSO ISSUED A FLASH FLOOD WATCH THROUGH 15Z THURSDAY FOR THE
THREAT OF TRAINING CONVECTION OVER OUR NORTHERN COUNTIES.
THE SET UP FOR ADDITIONAL CONVECTION TOMORROW AFTERNOON INTO FRIDAY
MORNING LOOKS SIMILAR TO TODAY...IF NOT BETTER...AS THE TROUGH
APPROACHES FROM THE WEST. SO HAVE CONTINUED THE FAIRLY HIGH CHANCES
FOR SHOWERS AND STORMS INTO LATE THURSDAY NIGHT/FRIDAY MORNING.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 521 PM EDT WED APR 8 2015
A COLD FRONT WILL BE PASSING SOUTHEAST THROUGH THE REGION AS THE
PERIOD STARTS. SHOWERS AND THUNDERSTORMS WILL BE ONGOING AHEAD OF
THE FRONT...BUT SHOULD COME TO AN ABRUPT END AFTER FROPA DURING
THE DAY. SURFACE HIGH PRESSURE BUILDING IN BEHIND THE FRONT WILL
THEN PROVIDE COOLER AND DRIER WEATHER THROUGH AT LEAST SUNDAY.
AS THE HIGH SLIPS TO THE EAST...WARM AIR ADVECTION AND A
WEAK WARM FRONT TRYING TO DEVELOP WILL PRESENT A LOW PROBABILITY
OF SHOWERS SUNDAY NIGHT AND MONDAY. A FEW THUNDERSTORMS COULD
SHOW UP ON MONDAY AFTERNOON. A BETTER CHANCE OF RAIN WILL ARRIVE
MONDAY NIGHT AND TUESDAY AS A MID/UPPER LEVEL TROUGH PUSHES IN
FROM THE WEST ALONG WITH THE FLOW OFF THE GULF. ONCE THIS IMPULSE
LIFTS OUT...WE WILL REMAIN IN THE WARM SECTOR. WEAKER DISTURBANCES
ALOFT MAY AID SHOWER/THUNDERSTORM DEVELOPMENT AT TIMES TUESDAY
NIGHT AND WEDNESDAY...BUT THE TIMING WILL BE NONSPECIFIC AT THIS
LONG RANGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 231 PM EDT WED APR 8 2015
TAIL END OF A THUNDERSTORM COMPLEX IS AFFECTING THE EASTERN EDGE
OF THE FORECAST AREA AT THE START OF THE PERIOD. THIS SHOULD EXIT
LATE THIS AFTERNOON. ADDITIONAL SHOWERS AND THUNDERSTORMS MAY POP
UP...BUT THERE IS LOW CONFIDENCE AS TO TIMING/LOCATION/COVERAGE.
ASIDE FROM KSJS...HAVE ONLY USED VCTS IN TAFS THIS AFTERNOON.
FORECAST SOUNDINGS SUGGESTED A LESS FAVORABLE LOW LEVEL PROFILE
FOR CONVECTION DEVELOPING EARLY THIS EVENING...AND HAVE ALLOWED
FOR A BREAK IN CONVECTION DURING THE NIGHT. HOWEVER...THIS IS ONCE
AGAIN A LOW CONFIDENCE FORECAST...AND IF ANYTHING DEVELOPS AND
SHOWS PROMISE DURING THE NIGHT...THE FORECAST WILL BE SUBJECT TO
CHANGE. FORECAST SOUNDINGS SHOW A POTENTIAL FOR SOME THUNDERSTORMS
AS DESTABILIZATION OCCURS TOWARD THE END OF THE PERIOD...AND VCTS
WAS AGAIN USED. PRECIP MAY BRING IFR...AND COULD ALLOW FOG TO
DEVELOP TONIGHT IF THE LOW LEVELS ARE LEFT SATURATED ANYWHERE.
HOWEVER...WITHOUT CONFIDENCE IN THIS...HAVE USED PREVAILING VFR.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR KYZ044-050>052-
104.
&&
$$
SHORT TERM...JVM/GREIF
LONG TERM...HAL
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
313 PM EDT Wed Apr 8 2015
.SHORT TERM (Now through Thursday Night)...
Issued at 308 PM EDT Wed Apr 8 2015
...More Strong Storms Possible This Evening and Tomorrow...
Multiple boundaries have set up across the region this afternoon.
SPC mesoanalysis shows all the CIN from earlier in the day has
eroded and we have become moderately unstable with 2500-3500 J/kg CAPE.
A Severe Thunderstorm Watch has been issued for southern Indiana for
this afternoon and early evening. However, given the multiple
boundaries and possibility for strong storms elsewhere around the
forecast area, extensions to the Watch are not out of the question
this afternoon. Large hail and damaging winds will be the main
threats this afternoon, though a tornado or two cannot be ruled out
completely. The other concern for tonight will be the possibility of
training thunderstorms, particularly across southern IN and north
central KY. The latest runs of the HRRR have been suggesting this.
Given that flash flood values are under an inch an hour and storms
may train in this area, have gone ahead and issued a Flash Flood
Watch starting late this afternoon and continuing through tomorrow
night.
There should be a relative lull in the storms for much of the
overnight period as any storms that develop this afternoon will move
out late this evening. Think another complex associated with a weak
upper level wave will move in early tomorrow morning and continue
through the morning hours. Some small hail and gusty winds will be
possible with these storms.
There should be at least a short break in storm coverage tomorrow
afternoon ahead of the more significant chance for severe weather
along and ahead of the cold front tomorrow night. Moisture will pool
ahead of the front with strong southerly winds through the afternoon
tomorrow. Forcing will come from the upper level trough moving in
and an upper level jet. Shear will increase and hodographs exhibit
favorable clockwise curving tomorrow night. A broken line of showers
and thunderstorms looks to develop to our west congeal into a line
as it moves into the forecast area tomorrow evening. Damaging winds
will be the the main threat with the squall line, with a few
embedded tornadoes possible. If any cells do develop ahead of the
main line hail could be a threat as well.
Due to the repeated areas of convection moving across the region,
have kept the Flash Flood Watch in place through tomorrow night.
Repeated rains will only exacerbate or renew flooding problems.
.LONG TERM (Friday through Wednesday)...
Issued at 241 PM EDT Wed Apr 8 2015
Not much has changed in the thinking for the long term period. Due
to the ongoing storms an updated discussion will not be issued this
afternoon. The previous discussion is below.
Previous discussion
-------------------
Cold front should pass through the area during the pre-dawn hours
Friday in our west then sweep across the rest of central Kentucky
during the early morning hours. Westerly flow will bring in a drier
and quieter pattern Friday night.
Plan on a pleasant, sunny and seasonable Saturday with high pressure
over the lower Ohio Valley. Sunday will start off in similar fashion
but as the high quickly moves to the east, southerly return flow
will begin to push another slug of warm, moist air to the region.
Shower chances return Sunday night through Monday as a trough digs
across the central Plains. High-end chance to likely POPs look
reasonable early next week with near normal temperatures.
&&
.AVIATION (18Z TAF Update)...
Updated at 1248 PM EDT Wed Apr 8 2015
Scattered thunderstorms are still expected to develop this
afternoon, though have pushed back the timing of VCTS in the TAFs
for a couple of hours. There is still a lot of uncertainty in when
and where the storms will develop so have kept the VCTS as opposed
to introducing TSRA at this time. Those with aviation interests
should keep a close eye on the radar this afternoon.
Expect a decrease in coverage of storms this evening with much of
the night remaining dry at the TAF sites. Another complex looks to
move in early tomorrow morning from the west bringing more showers
and thunderstorms. These should move out by early afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...FLASH FLOOD WATCH through late Thursday night FOR KYZ023>025-
028>043-045>049-053>057-066-067.
IN...FLASH FLOOD WATCH through late Thursday night FOR INZ076>079-083-
084-089>092.
&&
$$
Short Term........EER
Long Term.........BJS
Aviation..........EER
AREA FORECAST DISCUSSION
NWS JACKSON KY
231 PM EDT WED APR 8 2015
.UPDATE...
ISSUED AT 1215 PM EDT WED APR 8 2015
BIGGEST CHANGE TO THE FORECAST WAS INCREASING POPS ALONG THE
NORTHERN COUNTIES TO ACCOUNT FOR THE POSSIBLE SOUTHWESTERN
EXTENSION OF THE MCS CURRENTLY MOVING ACROSS SOUTHERN OHIO. HAVE INCLUDED
LARGE HAIL...DAMAGING WINDS...WITHIN THE WX GRIDS FOR THE NORTHERN
COUNTIES THROUGH THIS AFTERNOON TO CORRESPOND WITH THE SPC SEVERE
THUNDERSTORM WATCH 32. ADDITIONALLY...UPDATED T AND TD GRIDS TO
ALIGN THEM WITH MOST RECENT OBS. SENT UPDATED GRIDS TO WEB SERVERS
AND NDFD.
UPDATE ISSUED AT 745 AM EDT WED APR 8 2015
THE ARRIVAL OF LOWER CLOUDS FROM THE WEST HAS ALLOWED THE EARLIER
DENSE FOG TO BREAK UP AROUND DAWN. ACCORDINGLY...THIS UPDATE WAS
MAINLY TO REMOVE THE ADVISORY AND FOG MENTION...BUT ALSO UPDATED
THE POPS THROUGH NOON AND ADJUSTED TEMPS/DEW POINTS PER THE
LATEST OBS AND TRENDS. THE GRIDS HAVE BEEN SENT TO THE NDFD AND
WEB SERVERS ALONG WITH UPDATES TO THE ZFP AND HWO.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM EDT WED APR 8 2015
07Z SFC ANALYSIS SHOWS A STATIONARY BOUNDARY JUST NORTH OF
KENTUCKY PLACING THE AREA IN A WARM AND HUMID AIR MASS. THE
CONVECTION OF THE PAST DAY AND EVENING LEFT PLENTY OF GROUND
MOISTURE BEHIND AND NOW THAT CLOUDS ARE CLEARING OFF TO THE
EAST...EXPECT WIDESPREAD FOG TO DEVELOP AND BECOME LOCALLY DENSE
THIS MORNING. ALREADY JKL...SME...AND LOZ ARE SEEING DENSE FOG. AS
A RESULT...A DENSE FOG ADVISORY MAY BE NEEDED FOR MUCH OF THE
AREA THROUGH DAWN. OTHERWISE...TEMPERATURES ARE IN THE MID TO
UPPER 50S FOR MOST LOCATIONS WHILE DEW POINTS ARE GENERALLY
WITHIN A DEGREE OF THE DRY BULB TEMP...ALSO WINDS REMAIN LIGHT AND
VARIABLE.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST. THEY ALL SHOW SOUTHWEST FLOW OVER
KENTUCKY WITH PACKETS OF ENERGY PASSING THROUGH THE REGION EVERY
FEW HOURS. SOME HEIGHT FALLS WILL GET INTO THE MIX LATE IN THE
PERIOD ON THURSDAY AS A LARGER TROUGH SWEEPS EAST AND INTO THE
UPPER MIDWEST. THE KEY TO THIS UNSETTLED PATTERN WILL BE THE
SMALLER FEATURES THAT THE HIGHER RESOLUTION MODELS HAVE A BETTER
CHANCE OF CATCHING. EVEN SO...THE CONFIDENCE IN ANY PARTICULAR
SOLUTION IS LOW SO THE FORECAST HAS AN ELEMENT OF HEDGING TO IT
WITH THE HRRR AND NAM12 FAVORED. THE NAM12 ACTUALLY DID A DECENT
JOB DEPICTING THE CONVECTION OF THE PAST DAY SO AM INCLINED TO
GIVE IT HIGHER WEIGHTING TODAY.
SENSIBLE WEATHER WILL LIKELY BE A REPEAT OF TUESDAY WITH A CLUSTER
OF STRONG TO SEVERE THUNDERSTORMS POSSIBLY DEVELOPING BY EARLY
AFTERNOON AND TRACKING THROUGH THE NORTHERN AND CENTRAL PORTION
OF THE CWA. THIS IS THE SAME PLACE THAT WAS HIT HARD YESTERDAY AND
PWS WILL BE SIMILAR TODAY...SO CONSIDERED A FLASH FLOOD WATCH FOR
THESE LOCATIONS. HOWEVER...THE UNCERTAINTY IS STILL TOO HIGH
BARRING OBVIOUS UPSTREAM DEVELOPMENT SO WILL HIT THIS THREAT WITH
AN SPS FOR NOW. THE CONVECTION SHOULD DIE DOWN LATER IN THE
EVENING WITH PATCHY FOG...LOCALLY DENSE AGAIN...A CONCERN. THE
SET UP REMAINS SIMILAR FOR STORMS ON THURSDAY...IF NOT A TAD
BETTER AS THE MAIN TROUGH APPROACHES. ACCORDINGLY...HAVE CONTINUED
THE FAIRLY HIGH CHANCES FOR SHOWERS AND STORMS INTO THURSDAY
AFTERNOON AND EVENING.
AGAIN USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR
THE WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON
TERRAIN FOR TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSE
TO OR A BIT HIGHER THAN A BLEND OF THE MAV AND MET VALUES THROUGH
THE PERIOD.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 421 AM EDT WED APR 8 2015
AN UPPER LEVEL TROUGH...WITH SEVERAL SHORTWAVES EMBEDDED AND
ROTATING WITHIN IT...WILL PUSH FROM THE UPPER MISSISSIPPI VALLEY
EASTWARD FROM 0Z FRIDAY AND THROUGH THE DAY FRIDAY. OVERNIGHT FRIDAY
AND INTO THE DAY SATURDAY...THIS WAVE WILL WEAKEN AND CONTINUE TO
SHIFT EASTWARD...WHILE BUILDING HEIGHTS AND DEAMPLIFIED RIDGING
TAKES HOLD ACROSS THE OHIO RIVER VALLEY. LONG RANGE MODELS ARE IN
AGREEMENT OF THIS FLOW BECOMING ZONAL THROUGH SUNDAY...WITH A
SHORTWAVE DEVELOPING AND RIDING EASTWARD ACROSS KY LATE IN THE DAY
AND CONTINUING INTO MONDAY. UNFORTUNATELY FOR THE REST OF THE
EXTENDED...THE FEATURES ARE WELL AGREED UPON...BUT THE TIMING AND
PLACEMENT IS NOT. SUNDAY NIGHT/MONDAY MORNING A UPPER LEVEL CLOSED
LOW WILL LIKELY DEVELOP OVER THE TX/NM AREA...CAUSING AMPLIFICATION
AND EVENTUALLY FALLING HEIGHTS ACROSS KY AS THE LOW STARTS TO MOVE
NORTHEASTWARD DURING THE DAY MONDAY...LOSING CONSIDERABLE
STRENGTH AS IT REACHES THE UPPER MISSISSIPPI VALLEY BY TUESDAY.
MULTIPLE WEAKER SHORTWAVES WILL MOVE AROUND THESE CLOSED
LOWS...TRAVELING DIRECTLY INTO THE OHIO RIVER VALLEY.
AT THE SURFACE...A LOW PRESSURE SYSTEM WILL BE COLLOCATED WITH THE
UPPER LEVEL TROUGH ON FRIDAY AND FOLLOW THE TRACK NORTHEASTWARD
ACROSS THE GREAT LAKES. THIS WILL SEND A COLD FRONT EASTWARD AND
INTO THE STATE OF KY...STARTING OFF IN THE FAR WEST AROUND 0Z TO
3Z...AND REACHING THE JKL CWA BY LATE MORNING FRIDAY BEFORE QUICKLY
SHIFTING EASTWARD IN THE AFTERNOON...JUST AS THE UPPER LEVEL TROUGH
EXITS. BEST INSTABILITY AND MOISTURE WILL BE LOCATED ALONG AND JUST
AHEAD OF THE FRONT...WITH SHOWERS AND THUNDERSTORMS CHANCES EXPECTED
TO INCREASE THROUGH FRIDAY MORNING...BEFORE QUICKLY TAPERING OFF
ONCE THE FRONT PASSES THROUGH AND A STRONG SHOT OF DRIER AND COOLER
NRLY FLOW MOVES IN.
AS HEIGHTS BUILD SATURDAY INTO SATURDAY NIGHT...EXPECT SURFACE HIGH
PRESSURE TO BE IN CHARGE...WITH LIGHT WINDS AND GENERALLY CLEAR
SKIES. THE COULD CREATE SOME RIDGE VALLEY SPLIT CONDITIONS FOR
OVERNIGHT LOWS...AS WAS REFLECTED IN THE FORECAST. BY SUNDAY...THE
NEXT SHORTWAVE WILL BEGIN ENCROACHING UPON THE REGION...WITH YET
ANOTHER SURFACE LOW LOCATED JUST TO OUR SW. STRONG SRLY FLOW WILL
TAKE HOLD...WHICH COUPLED WITH INSTABILITY/LIFT FROM THE NEARBY
SYSTEM...WILL CREATE ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS SUNDAY EVENING AND INTO THE DAY MONDAY. FINALLY...THE
FUN CONTINUES AS SEVERAL MORE SHORTWAVES TRAVERSE THE UPPER LEVEL
TROUGH AND BRING UNSETTLED WEATHER TO THE REGION TO CONTINUE OUT THE
REMAINDER OF THE EXTENDED. GIVEN THE TIMING AND PLACEMENT
DISCREPANCIES OF THE LONG RANGE MODELS...CONTINUED WITH A MODEL
BLEND AT THIS TIME. HOWEVER...ONE NOTE...IF THE GFS40 MODEL PANS
OUT...SOME OF THESE SYSTEMS COULD PUT DOWN SOME HEAVY RAINS...WITH
PWATS TOPPING OUT ABOVE 1.3 TUESDAY AFTERNOON AND EVENING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 231 PM EDT WED APR 8 2015
TAIL END OF A THUNDERSTORM COMPLEX IS AFFECTING THE EASTERN EDGE
OF THE FORECAST AREA AT THE START OF THE PERIOD. THIS SHOULD EXIT
LATE THIS AFTERNOON. ADDITIONAL SHOWERS AND THUNDERSTORMS MAY POP
UP...BUT THERE IS LOW CONFIDENCE AS TO TIMING/LOCATION/COVERAGE.
ASIDE FROM KSJS...HAVE ONLY USED VCTS IN TAFS THIS AFTERNOON.
FORECAST SOUNDINGS SUGGESTED A LESS FAVORABLE LOW LEVEL PROFILE
FOR CONVECTION DEVELOPING EARLY THIS EVENING...AND HAVE ALLOWED
FOR A BREAK IN CONVECTION DURING THE NIGHT. HOWEVER...THIS IS ONCE
AGAIN A LOW CONFIDENCE FORECAST...AND IF ANYTHING DEVELOPS AND
SHOWS PROMISE DURING THE NIGHT...THE FORECAST WILL BE SUBJECT TO
CHANGE. FORECAST SOUNDINGS SHOW A POTENTIAL FOR SOME THUNDERSTORMS
AS DESTABILIZATION OCCURS TOWARD THE END OF THE PERIOD...AND VCTS
WAS AGAIN USED. PRECIP MAY BRING IFR...AND COULD ALLOW FOG TO
DEVELOP TONIGHT IF THE LOW LEVELS ARE LEFT SATURATED ANYWHERE.
HOWEVER...WITHOUT CONFIDENCE IN THIS...HAVE USED PREVAILING VFR.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JVM
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
218 PM EDT WED APR 8 2015
.UPDATE...
ISSUED AT 218 PM EDT WED APR 8 2015
DID A QUICK DATA LOAD AND BLEND TO UPDATE GRIDS WITH MOST RECENT
OBS. ALSO ADJUSTED POPS/SKY PER LATEST TRENDS WITH MCS THAT
CONTINUES TO PUSH ESE.
UPDATE ISSUED AT 1215 PM EDT WED APR 8 2015
BIGGEST CHANGE TO THE FORECAST WAS INCREASING POPS ALONG THE
NORTHERN COUNTIES TO ACCOUNT FOR THE POSSIBLE SOUTHWESTERN
EXTENSION OF THE MCS CURRENTLY MOVING ACROSS SOUTHERN OHIO. HAVE INCLUDED
LARGE HAIL...DAMAGING WINDS...WITHIN THE WX GRIDS FOR THE NORTHERN
COUNTIES THROUGH THIS AFTERNOON TO CORRESPOND WITH THE SPC SEVERE
THUNDERSTORM WATCH 32. ADDITIONALLY...UPDATED T AND TD GRIDS TO
ALIGN THEM WITH MOST RECENT OBS. SENT UPDATED GRIDS TO WEB SERVERS
AND NDFD.
UPDATE ISSUED AT 745 AM EDT WED APR 8 2015
THE ARRIVAL OF LOWER CLOUDS FROM THE WEST HAS ALLOWED THE EARLIER
DENSE FOG TO BREAK UP AROUND DAWN. ACCORDINGLY...THIS UPDATE WAS
MAINLY TO REMOVE THE ADVISORY AND FOG MENTION...BUT ALSO UPDATED
THE POPS THROUGH NOON AND ADJUSTED TEMPS/DEWPOINTS PER THE LATEST
OBS AND TRENDS. THE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS ALONG WITH UPDATES TO THE ZFP AND HWO.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM EDT WED APR 8 2015
07Z SFC ANALYSIS SHOWS A STATIONARY BOUNDARY JUST NORTH OF
KENTUCKY PLACING THE AREA IN A WARM AND HUMID AIR MASS. THE
CONVECTION OF THE PAST DAY AND EVENING LEFT PLENTY OF GROUND
MOISTURE BEHIND AND NOW THAT CLOUDS ARE CLEARING OFF TO THE
EAST...EXPECT WIDESPREAD FOG TO DEVELOP AND BECOME LOCALLY DENSE
THIS MORNING. ALREADY JKL...SME...AND LOZ ARE SEEING DENSE FOG. AS
A RESULT...A DENSE FOG ADVISORY MAY BE NEEDED FOR MUCH OF THE
AREA THROUGH DAWN. OTHERWISE...TEMPERATURES ARE IN THE MID TO
UPPER 50S FOR MOST LOCATIONS WHILE DEWPOINTS ARE GENERALLY WITHIN
A DEGREE OF THE DRY BULB TEMP...ALSO WINDS REMAIN LIGHT AND
VARIABLE.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST. THEY ALL SHOW SOUTHWEST FLOW OVER
KENTUCKY WITH PACKETS OF ENERGY PASSING THROUGH THE REGION EVERY
FEW HOURS. SOME HEIGHT FALLS WILL GET INTO THE MIX LATE IN THE
PERIOD ON THURSDAY AS A LARGER TROUGH SWEEPS EAST AND INTO THE
UPPER MIDWEST. THE KEY TO THIS UNSETTLED PATTERN WILL BE THE
SMALLER FEATURES THAT THE HIGHER RESOLUTION MODELS HAVE A BETTER
CHANCE OF CATCHING. EVEN SO...THE CONFIDENCE IN ANY PARTICULAR
SOLUTION IS LOW SO THE FORECAST HAS AN ELEMENT OF HEDGING TO IT
WITH THE HRRR AND NAM12 FAVORED. THE NAM12 ACTUALLY DID A DECENT
JOB DEPICTING THE CONVECTION OF THE PAST DAY SO AM INCLINED TO
GIVE IT HIGHER WEIGHTING TODAY.
SENSIBLE WEATHER WILL LIKELY BE A REPEAT OF TUESDAY WITH A CLUSTER
OF STRONG TO SEVERE THUNDERSTORMS POSSIBLY DEVELOPING BY EARLY
AFTERNOON AND TRACKING THROUGH THE NORTHERN AND CENTRAL PORTION
OF THE CWA. THIS IS THE SAME PLACE THAT WAS HIT HARD YESTERDAY AND
PWS WILL BE SIMILAR TODAY...SO CONSIDERED A FLASH FLOOD WATCH FOR
THESE LOCATIONS. HOWEVER...THE UNCERTAINTY IS STILL TOO HIGH
BARRING OBVIOUS UPSTREAM DEVELOPMENT SO WILL HIT THIS THREAT WITH
AN SPS FOR NOW. THE CONVECTION SHOULD DIE DOWN LATER IN THE
EVENING WITH PATCHY FOG...LOCALLY DENSE AGAIN...A CONCERN. THE
SET UP REMAINS SIMILAR FOR STORMS ON THURSDAY...IF NOT A TAD
BETTER AS THE MAIN TROUGH APPROACHES. ACCORDINGLY...HAVE CONTINUED
THE FAIRLY HIGH CHANCES FOR SHOWERS AND STORMS INTO THURSDAY
AFTERNOON AND EVENING.
AGAIN USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR
THE WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON
TERRAIN FOR TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSE
TO OR A BIT HIGHER THAN A BLEND OF THE MAV AND MET VALUES THROUGH
THE PERIOD.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 421 AM EDT WED APR 8 2015
AN UPPER LEVEL TROUGH...WITH SEVERAL SHORTWAVES EMBEDDED AND
ROTATING WITHIN IT...WILL PUSH FROM THE UPPER MISSISSIPPI VALLEY
EASTWARD FROM 0Z FRIDAY AND THROUGH THE DAY FRIDAY. OVERNIGHT FRIDAY
AND INTO THE DAY SATURDAY...THIS WAVE WILL WEAKEN AND CONTINUE TO
SHIFT EASTWARD...WHILE BUILDING HEIGHTS AND DEAMPLIFIED RIDGING
TAKES HOLD ACROSS THE OHIO RIVER VALLEY. LONG RANGE MODELS ARE IN
AGREEMENT OF THIS FLOW BECOMING ZONAL THROUGH SUNDAY...WITH A
SHORTWAVE DEVELOPING AND RIDING EASTWARD ACROSS KY LATE IN THE DAY
AND CONTINUING INTO MONDAY. UNFORTUNATELY FOR THE REST OF THE
EXTENDED...THE FEATURES ARE WELL AGREED UPON...BUT THE TIMING AND
PLACEMENT IS NOT. SUNDAY NIGHT/MONDAY MORNING A UPPER LEVEL CLOSED
LOW WILL LIKELY DEVELOP OVER THE TX/NM AREA...CAUSING AMPLIFICATION
AND EVENTUALLY FALLING HEIGHTS ACROSS KY AS THE LOW STARTS TO MOVE
NEWARD DURING THE DAY MONDAY...LOSING CONSIDERABLE STRENGTH AS IT
REACHES THE UPPER MISSISSIPPI VALLEY BY TUESDAY. MULTIPLE WEAKER
SHORTWAVES WILL MOVE AROUND THESE CLOSED LOWS...TRAVELING DIRECTLY
INTO THE OHIO RIVER VALLEY.
AT THE SURFACE...A LOW PRESSURE SYSTEM WILL BE COLLOCATED WITH THE
UPPER LEVEL TROUGH ON FRIDAY AND FOLLOW THE TRACK NORTHEASTWARD
ACROSS THE GREAT LAKES. THIS WILL SEND A COLD FRONT EASTWARD AND
INTO THE STATE OF KY...STARTING OFF IN THE FAR WEST AROUND 0Z TO
3Z...AND REACHING THE JKL CWA BY LATE MORNING FRIDAY BEFORE QUICKLY
SHIFTING EASTWARD IN THE AFTERNOON...JUST AS THE UPPER LEVEL TROUGH
EXITS. BEST INSTABILITY AND MOISTURE WILL BE LOCATED ALONG AND JUST
AHEAD OF THE FRONT...WITH SHOWERS AND THUNDERSTORMS CHANCES EXPECTED
TO INCREASE THROUGH FRIDAY MORNING...BEFORE QUICKLY TAPERING OFF
ONCE THE FRONT PASSES THROUGH AND A STRONG SHOT OF DRIER AND COOLER
NRLY FLOW MOVES IN.
AS HEIGHTS BUILD SATURDAY INTO SATURDAY NIGHT...EXPECT SURFACE HIGH
PRESSURE TO BE IN CHARGE...WITH LIGHT WINDS AND GENERALLY CLEAR
SKIES. THE COULD CREATE SOME RIDGE VALLEY SPLIT CONDITIONS FOR
OVERNIGHT LOWS...AS WAS REFLECTED IN THE FORECAST. BY SUNDAY...THE
NEXT SHORTWAVE WILL BEGIN ENCROACHING UPON THE REGION...WITH YET
ANOTHER SURFACE LOW LOCATED JUST TO OUR SW. STRONG SRLY FLOW WILL
TAKE HOLD...WHICH COUPLED WITH INSTABILITY/LIFT FROM THE NEARBY
SYSTEM...WILL CREATE ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS SUNDAY EVENING AND INTO THE DAY MONDAY. FINALLY...THE
FUN CONTINUES AS SEVERAL MORE SHORTWAVES TRAVERSE THE UPPER LEVEL
TROUGH AND BRING UNSETTLED WEATHER TO THE REGION TO CONTINUE OUT THE
REMAINDER OF THE EXTENDED. GIVEN THE TIMING AND PLACEMENT
DISCREPANCIES OF THE LONG RANGE MODELS...CONTINUED WITH A MODEL
BLEND AT THIS TIME. HOWEVER...ONE NOTE...IF THE GFS40 MODEL PANS
OUT...SOME OF THESE SYSTEMS COULD PUT DOWN SOME HEAVY RAINS...WITH
PWATS TOPPING OUT ABOVE 1.3 TUESDAY AFTERNOON AND EVENING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 800 AM EDT WED APR 8 2015
THE FOG PROVED TO BE FLEETING THIS MORNING AS A LAYER OF LOW TO
MID CLOUDS MOVED IN AND CLEARED OUT THE LOWER VIS. LATER TODAY
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS EXPECTED THIS
AFTERNOON. HAVE STAYED WITH A VCTS FOR THIS WITH MORE REFINEMENT
POSSIBLE WITH FUTURE TAF ISSUANCES AS THE TIMING AND EFFECTS OF
THIS NEXT WAVE BECOME MORE CLEAR. AFTER THIS WAVE OF ACTIVITY
PASSES PATCHY FOG WILL BE A POSSIBILITY MAINLY...IN THE
VALLEYS...AND HAVE ADDED SOME TO THE SME AND LOZ TAFS. WINDS WILL
REMAIN MAINLY LIGHT FROM THE SOUTH...OUTSIDE OF ANY THUNDERSTORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JVM
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS JACKSON KY
1213 PM EDT WED APR 8 2015
.UPDATE...
ISSUED AT 1215 PM EDT WED APR 8 2015
BIGGEST CHANGE TO THE FORECAST WAS INCREASING POPS ALONG THE
NORTHERN COUNTIES TO ACCOUNT FOR THE POSSIBLE SOUTHWESTERN
EXTENSION OF THE MCS CURRENTLY MOVING ACROSS SOUTHERN OHIO. HAVE INCLUDED
LARGE HAIL...DAMAGING WINDS...WITHIN THE WX GRIDS FOR THE NORTHERN
COUNTIES THROUGH THIS AFTERNOON TO CORRESPOND WITH THE SPC SEVERE
THUNDERSTORM WATCH 32. ADDITIONALLY...UPDATED T AND TD GRIDS TO
ALIGN THEM WITH MOST RECENT OBS. SENT UPDATED GRIDS TO WEB SERVERS
AND NDFD.
UPDATE ISSUED AT 745 AM EDT WED APR 8 2015
THE ARRIVAL OF LOWER CLOUDS FROM THE WEST HAS ALLOWED THE EARLIER
DENSE FOG TO BREAK UP AROUND DAWN. ACCORDINGLY...THIS UPDATE WAS
MAINLY TO REMOVE THE ADVISORY AND FOG MENTION...BUT ALSO UPDATED
THE POPS THROUGH NOON AND ADJUSTED TEMPS/DEWPOINTS PER THE LATEST
OBS AND TRENDS. THE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS ALONG WITH UPDATES TO THE ZFP AND HWO.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM EDT WED APR 8 2015
07Z SFC ANALYSIS SHOWS A STATIONARY BOUNDARY JUST NORTH OF
KENTUCKY PLACING THE AREA IN A WARM AND HUMID AIR MASS. THE
CONVECTION OF THE PAST DAY AND EVENING LEFT PLENTY OF GROUND
MOISTURE BEHIND AND NOW THAT CLOUDS ARE CLEARING OFF TO THE
EAST...EXPECT WIDESPREAD FOG TO DEVELOP AND BECOME LOCALLY DENSE
THIS MORNING. ALREADY JKL...SME...AND LOZ ARE SEEING DENSE FOG. AS
A RESULT...A DENSE FOG ADVISORY MAY BE NEEDED FOR MUCH OF THE
AREA THROUGH DAWN. OTHERWISE...TEMPERATURES ARE IN THE MID TO
UPPER 50S FOR MOST LOCATIONS WHILE DEWPOINTS ARE GENERALLY WITHIN
A DEGREE OF THE DRY BULB TEMP...ALSO WINDS REMAIN LIGHT AND
VARIABLE.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST. THEY ALL SHOW SOUTHWEST FLOW OVER
KENTUCKY WITH PACKETS OF ENERGY PASSING THROUGH THE REGION EVERY
FEW HOURS. SOME HEIGHT FALLS WILL GET INTO THE MIX LATE IN THE
PERIOD ON THURSDAY AS A LARGER TROUGH SWEEPS EAST AND INTO THE
UPPER MIDWEST. THE KEY TO THIS UNSETTLED PATTERN WILL BE THE
SMALLER FEATURES THAT THE HIGHER RESOLUTION MODELS HAVE A BETTER
CHANCE OF CATCHING. EVEN SO...THE CONFIDENCE IN ANY PARTICULAR
SOLUTION IS LOW SO THE FORECAST HAS AN ELEMENT OF HEDGING TO IT
WITH THE HRRR AND NAM12 FAVORED. THE NAM12 ACTUALLY DID A DECENT
JOB DEPICTING THE CONVECTION OF THE PAST DAY SO AM INCLINED TO
GIVE IT HIGHER WEIGHTING TODAY.
SENSIBLE WEATHER WILL LIKELY BE A REPEAT OF TUESDAY WITH A CLUSTER
OF STRONG TO SEVERE THUNDERSTORMS POSSIBLY DEVELOPING BY EARLY
AFTERNOON AND TRACKING THROUGH THE NORTHERN AND CENTRAL PORTION
OF THE CWA. THIS IS THE SAME PLACE THAT WAS HIT HARD YESTERDAY AND
PWS WILL BE SIMILAR TODAY...SO CONSIDERED A FLASH FLOOD WATCH FOR
THESE LOCATIONS. HOWEVER...THE UNCERTAINTY IS STILL TOO HIGH
BARRING OBVIOUS UPSTREAM DEVELOPMENT SO WILL HIT THIS THREAT WITH
AN SPS FOR NOW. THE CONVECTION SHOULD DIE DOWN LATER IN THE
EVENING WITH PATCHY FOG...LOCALLY DENSE AGAIN...A CONCERN. THE
SET UP REMAINS SIMILAR FOR STORMS ON THURSDAY...IF NOT A TAD
BETTER AS THE MAIN TROUGH APPROACHES. ACCORDINGLY...HAVE CONTINUED
THE FAIRLY HIGH CHANCES FOR SHOWERS AND STORMS INTO THURSDAY
AFTERNOON AND EVENING.
AGAIN USED THE SHORTBLEND COMPOSITE MODEL AS A STARTING POINT FOR
THE WINDS/T/TD GRIDS THROUGH THE FIRST 18-24 HOURS AND THE
SUPERBLEND THEREAFTER. DID MAKE SOME MINOR ADJUSTMENTS BASED ON
TERRAIN FOR TONIGHT/S TEMPERATURES. AS FOR POPS...ENDED UP CLOSE
TO OR A BIT HIGHER THAN A BLEND OF THE MAV AND MET VALUES THROUGH
THE PERIOD.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 421 AM EDT WED APR 8 2015
AN UPPER LEVEL TROUGH...WITH SEVERAL SHORTWAVES EMBEDDED AND
ROTATING WITHIN IT...WILL PUSH FROM THE UPPER MISSISSIPPI VALLEY
EASTWARD FROM 0Z FRIDAY AND THROUGH THE DAY FRIDAY. OVERNIGHT FRIDAY
AND INTO THE DAY SATURDAY...THIS WAVE WILL WEAKEN AND CONTINUE TO
SHIFT EASTWARD...WHILE BUILDING HEIGHTS AND DEAMPLIFIED RIDGING
TAKES HOLD ACROSS THE OHIO RIVER VALLEY. LONG RANGE MODELS ARE IN
AGREEMENT OF THIS FLOW BECOMING ZONAL THROUGH SUNDAY...WITH A
SHORTWAVE DEVELOPING AND RIDING EASTWARD ACROSS KY LATE IN THE DAY
AND CONTINUING INTO MONDAY. UNFORTUNATELY FOR THE REST OF THE
EXTENDED...THE FEATURES ARE WELL AGREED UPON...BUT THE TIMING AND
PLACEMENT IS NOT. SUNDAY NIGHT/MONDAY MORNING A UPPER LEVEL CLOSED
LOW WILL LIKELY DEVELOP OVER THE TX/NM AREA...CAUSING AMPLIFICATION
AND EVENTUALLY FALLING HEIGHTS ACROSS KY AS THE LOW STARTS TO MOVE
NEWARD DURING THE DAY MONDAY...LOSING CONSIDERABLE STRENGTH AS IT
REACHES THE UPPER MISSISSIPPI VALLEY BY TUESDAY. MULTIPLE WEAKER
SHORTWAVES WILL MOVE AROUND THESE CLOSED LOWS...TRAVELING DIRECTLY
INTO THE OHIO RIVER VALLEY.
AT THE SURFACE...A LOW PRESSURE SYSTEM WILL BE COLLOCATED WITH THE
UPPER LEVEL TROUGH ON FRIDAY AND FOLLOW THE TRACK NORTHEASTWARD
ACROSS THE GREAT LAKES. THIS WILL SEND A COLD FRONT EASTWARD AND
INTO THE STATE OF KY...STARTING OFF IN THE FAR WEST AROUND 0Z TO
3Z...AND REACHING THE JKL CWA BY LATE MORNING FRIDAY BEFORE QUICKLY
SHIFTING EASTWARD IN THE AFTERNOON...JUST AS THE UPPER LEVEL TROUGH
EXITS. BEST INSTABILITY AND MOISTURE WILL BE LOCATED ALONG AND JUST
AHEAD OF THE FRONT...WITH SHOWERS AND THUNDERSTORMS CHANCES EXPECTED
TO INCREASE THROUGH FRIDAY MORNING...BEFORE QUICKLY TAPERING OFF
ONCE THE FRONT PASSES THROUGH AND A STRONG SHOT OF DRIER AND COOLER
NRLY FLOW MOVES IN.
AS HEIGHTS BUILD SATURDAY INTO SATURDAY NIGHT...EXPECT SURFACE HIGH
PRESSURE TO BE IN CHARGE...WITH LIGHT WINDS AND GENERALLY CLEAR
SKIES. THE COULD CREATE SOME RIDGE VALLEY SPLIT CONDITIONS FOR
OVERNIGHT LOWS...AS WAS REFLECTED IN THE FORECAST. BY SUNDAY...THE
NEXT SHORTWAVE WILL BEGIN ENCROACHING UPON THE REGION...WITH YET
ANOTHER SURFACE LOW LOCATED JUST TO OUR SW. STRONG SRLY FLOW WILL
TAKE HOLD...WHICH COUPLED WITH INSTABILITY/LIFT FROM THE NEARBY
SYSTEM...WILL CREATE ANOTHER ROUND OF SCATTERED SHOWERS AND
THUNDERSTORMS SUNDAY EVENING AND INTO THE DAY MONDAY. FINALLY...THE
FUN CONTINUES AS SEVERAL MORE SHORTWAVES TRAVERSE THE UPPER LEVEL
TROUGH AND BRING UNSETTLED WEATHER TO THE REGION TO CONTINUE OUT THE
REMAINDER OF THE EXTENDED. GIVEN THE TIMING AND PLACEMENT
DISCREPANCIES OF THE LONG RANGE MODELS...CONTINUED WITH A MODEL
BLEND AT THIS TIME. HOWEVER...ONE NOTE...IF THE GFS40 MODEL PANS
OUT...SOME OF THESE SYSTEMS COULD PUT DOWN SOME HEAVY RAINS...WITH
PWATS TOPPING OUT ABOVE 1.3 TUESDAY AFTERNOON AND EVENING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 800 AM EDT WED APR 8 2015
THE FOG PROVED TO BE FLEETING THIS MORNING AS A LAYER OF LOW TO
MID CLOUDS MOVED IN AND CLEARED OUT THE LOWER VIS. LATER TODAY
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS EXPECTED THIS
AFTERNOON. HAVE STAYED WITH A VCTS FOR THIS WITH MORE REFINEMENT
POSSIBLE WITH FUTURE TAF ISSUANCES AS THE TIMING AND EFFECTS OF
THIS NEXT WAVE BECOME MORE CLEAR. AFTER THIS WAVE OF ACTIVITY
PASSES PATCHY FOG WILL BE A POSSIBILITY MAINLY...IN THE
VALLEYS...AND HAVE ADDED SOME TO THE SME AND LOZ TAFS. WINDS WILL
REMAIN MAINLY LIGHT FROM THE SOUTH...OUTSIDE OF ANY THUNDERSTORMS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JVM
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
251 PM EDT WED APR 8 2015
.SYNOPSIS...
A COLD FRONT WILL CONTINUE TO DROP SOUTH AND WEST THROUGH OUR AREA
THIS MORNING. THE BOUNDARY WILL STALL OUT OVER THE POTOMAC
HIGHLANDS INTO SOUTHERN VIRGINIA THIS AFTERNOON THROUGH THURSDAY
BEFORE RETURNING AS A WARM FRONT LATE THURSDAY NIGHT AND FRIDAY. A
COLD FRONT WILL PASS THROUGH THE REGION FRIDAY NIGHT AND HIGH
PRESSURE WILL RETURN FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
A WEDGE OF HIGH PRESSURE WILL PERSIST ACROSS MOST OF THE MID-
ATLANTIC. THE FORWARD EXTENT OF THIS AIRMASS IS ACROSS CENTRAL
VIRGINIA. AN ADVANCING MCS WILL APPROACH CENTRAL VIRGINIA THIS
AFTERNOON.
A COLD FRONT SEPERATES COOL HIGH PRESSURE WITH A WARM UNSTABLE
AIRMASS. ON THE WARM SIDE...TEMPS HAVE RISEN TO NEAR 65 WITH
DEWPTS IN THE MID-UPPER 50S. A MCS WILL APPROACH EASTERN WEST
VIRGINIA AND CENTRAL VIRGINIA THIS AFTERNOON. STRONG AND SEVERE
THUNDERSTORMS ARE POSSIBLE ACROSS THE VIRGINIA AND SOUTHERN
POTOMAC HIGHLANDS AND CENTRAL SHENANDOAH VALLEY AS INSTABILITY
HAS RISEN TO ABOVE 1000 J/KG WITH 30KTS OF BULK 0-6 KM SHEAR. THIS
SYSTEM HAS A HISTORY OF DAMAGING WINDS...LARGE HAIL AND FREQUENT
LIGHTNING. THERE HAS BEEN A SLIGHT DOWNWARD TREND IN ACTIVITY AS
IT APPROACHES VA BUT SOME POCKETS OF STRONG WINDS EXIST IN THE
LEADING EDGE OF THE CONVECTIVE LINE AND THEREFORE STORMS MAY
PRODUCE HAZARDOUS CONDITIONS. HRRR HAS BEEN CONSISTENT TODAY WITH
LINE REACHING THE MTNS. FURTHER NORTH AND EAST AND IN THE HIGH
PRESSURE WEDGE...ANY CONVECTIVE ACTIVITY WILL QUICKLY DISSAPATE AS
IT MOVES INTO A VERY STABLE ATMOSPHERE. RAIN WILL TAKE OVER AND
MOVE EASTWARD THIS EVENING.
SUBSIDENCE BEHIND THE MCS WILL LEAD TO A LULL OF WIDESPREAD RAIN
BUT LOW LEVEL SATURATION WILL MAINTAIN CHANCES OF DZ OR RAIN
THROUGH THE EVENING. NOTHING WILL PUSH THE WEDGE FROM PERSISTING
ACROSS THE MID- ATLANTIC THROUGH THURSDAY. THE COLD FRONT MAY
RETREAT FURTHER NORTH BUT TEMPS WILL STILL REMAIN BELOW CLIMO.
SLIGHT RIDGING ALOFT WILL ALLOW DISTURBANCES TO MOVE TO THE
NORTHWEST OF THE REGION. LITTLE FORCING WILL LIMIT WIDESPREAD RAIN
THURSDAY BUT LOW LEVEL SATURATION WILL ALLOW FOR DRIZZLE AT TIMES.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
A WARM FRONT WILL LIFT NORTH ACROSS THE REGION THURSDAY NIGHT. A
STRONG INVERSION WITH ADEQUATE SATURATION IS EXPECTED IN THE
BOUNDARY LAYER BUT SHOULD GRADUALLY WEAKEN THROUGHOUT THE NIGHT INTO
EARLY FRIDAY MORNING. EXPECT RAIN SHOWERS OR AREAS OF DRIZZLE ACROSS
PARTS OF THE REGION. LOW TEMPERATURES SHOULD BOTTOM OUT IN THE LOWER
40S IN NORTHEAST MARYLAND TO THE MIDDLE 50S IN THE CENTRAL
SHENANDOAH VALLEY. SHOULD ANY EASTERLY COMPONENT TO THE WIND VEER
AROUND TO MORE SOUTHERLY...THEN LOW TEMPERATURES WILL BECOME HIGHER
THURSDAY NIGHT. THE LATEST MODEL RUNS OF THE NAM AND GFS HAVE
GOOD AGREEMENT IN THURSDAY`S LOW TEMPERATURES.
ON FRIDAY...LOW PRESSURE WILL MOVE NORTHEAST ACROSS THE GREAT LAKES.
A COUPLE OF RAIN SHOWERS AND PATCHY DRIZZLE EARLY FRIDAY WILL LINGER
BUT BECOME MORE SPARSE AS MILDER AIR BECOMES MORE DOMINANT BOTH
ALOFT AND AT THE SURFACE. WITH A WARM FRONT NOW TO THE NORTH OF THE
REGION AND A PERSISTENT...YET INCREASING...SOUTHERLY FLOW
EVOLVING...TEMPERATURES SHOULD QUICKLY SORE UPWARDS FROM THE 40S AND
50S TO THE 70S AND A FEW 80S BY MID-AFTERNOON FRIDAY.
ANY BREAKS IN CLOUD COVER WILL LEAD TO GREATER INSTABILITY DURING
THE MORNING AND AFTERNOON HOURS. WE ARE EXPECTING A COLD
FRONT...ATTACHED TO THE GREAT LAKES` LOW PRESSURE...TO PUSH ACROSS
THE REGION FROM WEST TO EAST. THERE IS STILL UNCERTAINTY IN THE
TIMING OF THE COLD FRONTAL PASSAGE. AS OF NOW...TIMING APPEARS TO BE
AROUND NOON IN THE POTOMAC HIGHLANDS...LATE AFTERNOON ALONG I-
95 AND MID-EVENING LOWER SOUTHERN MARYLAND. SHOWERS SHOULD BE
HEAVY AND THUNDERSTORMS STRONG TO SEVERE. MUCH OF ANY SEVERE
THUNDERSTORMS WOULD BE MORE EXPECTED FROM THE BLUE RIDGE
MOUNTAINS TO THE CHESAPEAKE BAY AND SOUTHERN MARYLAND. THERE
IS CURRENTLY A SLIGHT RISK FOR AN AREA FROM ALONG I-95 TO THE
SOUTH AND EAST FOR FRIDAY INTO FRIDAY EVENING. THE MAIN THREAT WOULD
BE DAMAGING WIND GUSTS AND LARGE HAIL.
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE MIDWEST BEGINNING
FRIDAY NIGHT. TEMPERATURES AND DEWPOINT TEMPERATURES WILL DROP AS
COOLER AND DRIER AIR WORKS INTO THE REGION. OUR CURRENT FORECAST HAS
LOW TEMPERATURES FRIDAY NIGHT IN THE UPPER 40S TO NEAR 50.
HOWEVER...IF ENOUGH COOLER AIR ALOFT MOVES IN QUICKER THAN
EXPECTED...THEN LOW TEMPERATURES MAY BE ANOTHER 5 DEGREES COOLER.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
SURFACE HIGH OVER THE REGION SATURDAY WILL MOVE OFFSHORE BY
SUNDAY AFTERNOON. DRY MILD CONDITIONS ARE EXPECTED INTO THE EARLY
HALF OF THE UPCOMING WEEK. RAINFALL ASSOCIATED WITH A SURFACE LOW
OVER THE SOUTHERN PLAINS WILL AFFECT THE MID ATLANTIC REGION BY
LATE MONDAY OR EARLY TUESDAY AND CONTINUE THROUGH MIDWEEK. A WARM
FRONT WILL CROSS THE REGION DURING THE DAY TUESDAY BRINGING WARMER
THAN NORMAL TEMPERATURES TO THE AREA. THE LOW WILL CROSS THE
REGION AND MOVE OFFSHORE WEDNESDAY.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
MVFR/IFR CONDITIONS WILL PERSIST THIS AFTERNOON AS A WEDGE OF HIGH
PRESSURE WEDGES INTO THE MID-ATLANTIC. CIGS WILL LOWER TONIGHT AND
IFR WITH SUB-IFR CONDITIONS EXPECTED INTO THURSDAY MORNING. -
RADZ IS POSSIBLE TONIGHT. MVFR VSBYS ARE EXPECTED THIS AFTERNOON
THROUGH THURSDAY MORNING. CIGS SHOULD BECOME MVFR BY MID-MORNING
THURSDAY AND PERSIST THROUGH THU AFTERNOON.
A COLD FRONT WILL SLOWLY RETREAT TO THE NORTH THURSDAY NIGHT INTO
FRIDAY MORNING. IFR CONDITIONS EXPECTED THURSDAY NIGHT BEFORE
REACHING VFR FRIDAY MID-MORNING. PERIODS OF MVFR/IFR CONDITIONS
POSSIBLE WITH SHOWERS AND NUMEROUS THUNDERSTORMS. SOME
THUNDERSTORMS MAY PRODUCE GUSTY WINDS AND LARGE HAIL.
&&
.MARINE...
A RIDGE AXIS WILL PERSIST OVER THE WATERS THROUGH THURSDAY. THE
GRADIENT HAS LED TO GUSTS 15-20KTS AT TIMES. SCA IS IN EFFECT THIS
AFTERNOON. MIXING SHOULD BE REDUCED THIS EVENING. THE GRADIENT
SHOULD RELAX THURSDAY AND SCA ARE NOT EXPECTED.
NO MARINE HAZARDS EXPECTED THURSDAY NIGHT. SMALL CRAFT ADVISORY
CONDITIONS POSSIBLE FRIDAY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR
ANZ530>543.
&&
$$
SYNOPSIS...HAS
NEAR TERM...HAS
SHORT TERM...KLW
LONG TERM...CEM
AVIATION...HAS/KLW
MARINE...HAS/KLW
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
219 PM EDT WED APR 8 2015
.SYNOPSIS...
A BACKDOOR COLD FRONT WILL DROP SOUTH ACROSS THE LOCAL AREA EARLY
TODAY THROUGH TONIGHT. THE FRONT THEN WEAKENS AND LIFTS BACK
NORTH AS A WARM FRONT ON THURSDAY. ANOTHER COLD FRONT CROSSES THE
REGION LATE FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
FORECAST UPDATED TO LWR POPS FOR THE REMAINDER OF THE DAY AND MAKE
CHANGES TO HRLY TEMPS WHICH ARE QUITE TRICKY DUE TO A SLOWLY
SAGGING COLD FRNT THRU THE AREA.
PREVIOUS DISCUSSION...
LATEST SURFACE ANALYSIS FEATURES SFC LOW PRESSURE IN PLACE OVER
THE CENTRAL HIGH PLAINS, WITH A QUASI- STATIONARY FRONTAL BOUNDARY
DRAPED ACROSS THE MID MS VLY OVER INTO THE OHIO VLY AND THE LWR
EASTERN SHORE. NOTING SOME POCKETS OF SHRAS ACROSS THE AREA ON
REGIONAL RADAR MOSAIC IN ASSOCIATION WITH A FEW WEAK DISTURBANCES.
A FEW SCT SHRAS ARE CURRENTLY PUSHING EAST ON THE SOUTHERN
PERIPHERY OF THE FRONTAL ZONE ACROSS THE LWR EASTERN SHORE THIS
MORNING. MEANWHILE TO THE WEST, A MORE SUBSTANTIAL AREA OF SHRAS
IN ASSOCIATION WITH DECAYING CONVECTIVE COMPLEX THAT ROLLED ACROSS
THE OHIO RVR VALLEY LAST NIGHT IS CURRENTLY PUSHING FROM E
WV/WESTERN VA OVER TO THE PIEDMONT IN THE FORM OF SOME LIGHT TO
MODERATE RAIN SHRAS. LATEST HRRR AND TO A LESSER EXTENT THE 00Z
NAM HAVE BEST HANDLED THIS FEATURE THUS FAR... AND HAVE THEREFORE
LEANED THE FORECAST IN THIS DIRECTION FOR THE NEAR TERM. HAVE GONE
WITH A BRIEF 4-6 HR PERIOD OF LIKELY SHRAS THIS MORNING MAINLY IN
THE WARM SECTOR...WITH THE BEST RAIN CHANCES FROM THE EASTERN
PIEDMONT/WEST OF RIC METRO EARLY THIS MORNING...REACHING THE I-95
CORRIDOR BY DAWN AND EVENTUALLY SOUTH CENTRAL VA/HAMPTON ROADS BY
MID TO LATE MORNING. EXPECT LESS SHRA ACTIVITY THIS AFTN BEHIND
DEPARTING SHORTWAVE AND HV THEREFORE CUT BACK ON POP FOR THE AFTN.
EXPECT THE FRONT TO THE NORTH TO DROP SOUTH-SOUTHEAST IN BACKDOOR
FASHION THIS MORNING, BRINGING ABOUT A WIND SHIFT TO THE NE FROM
MIDDAY INTO THE AFTN. TEMPERATURES WILL STABILIZE TO FALL SLIGHTLY
ACROSS THE NORTHERN NECK/EASTERN SHORE, AS TEMPERATURES WARM INTO
THE LOW TO MID 70S IN THE WARM SECTOR OVER INLAND SECTIONS ALONG
AND SOUTH OF THE VA/NC BORDER. FARTHER NORTH, LOOK FOR HIGHS IN
THE U40S NEAR OCEAN CITY...LOW TO MID 50S OVER THE NORTHERN HALF
OF THE AREA.
EXPECT ANOTHER ROUND OF CONVECTION BY EARLY EVENING AS NEXT
DISTURBANCE NOW OVER THE MID MO VLY TRANSLATES EAST. WILL INCREASE
POP AGAIN BRIEFLY TONIGHT AS DISTURBANCE MOVES ALONG THE FRONT,
IN PLACE ALONG OR JUST SOUTH OF THE VA/NC BORDER THIS EVENING.
RAIN CHANCES DROP OFF AGAIN TONIGHT BEHIND THIS FEATURE
OVERNIGHT. COOLER TONIGHT IN MOIST NE FLOW BEHIND THE FRONT, WITH
LOWS IN THE 40S NE TO MID 50S SW SECTIONS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 448 AM EDT WED...
THE FRONT WILL WEAKEN, WITH DEVELOPING SW FLOW EVENTUALLY PUSHING
IT BACK NWD AS A WARM FRONT BY THU AFTN. HIGHS THU WILL RANGE
FROM THE 50S ON THE LWR ERN SHORE TO THE U60S TO L70S WITH MORE
TIME IN THE WARM SECTOR ACROSS FAR SWRN/WRN AREAS. HAVE MADE A
MODEST DOWNWARD ADJUSTMENT ACROSS THE NORTHERN HALF OF THE AREA
WITH ONGOING NE FLOW. POPS REMAIN IN CHANCE RANGE AS SEVERAL WEAK
DISTURBANCES WILL RESULT IN TWO PERIODS FOR SCT SHRAS...MAINLY
ACROSS THE NORTH IN THE MORNING AND ACROSS CENTRAL AND SOUTHERN
ZONES ALONG THE FROTNAL ZONE.
SFC LOW OVER THE PLAINS WILL TRACK NE INTO THE GREAT LAKES LATE
THU/FRI WITH THE ASSOCIATED COLD FRONT CROSSING INTO OUR AREA
FM THE WEST LATE IN THE DAY ON FRI/FRI NGT. CHANCES OF ADDITIONAL
SHRAS/STORMS INCREASE FM W TO E THRU THE DAY FRI...WITH THE BEST
CHANCE (60% POPS) IN THE AFTN/EVE HRS. SOME TSTMS MAY HAVE STRONG
GUSTY WINDS AND HEAVY RAIN...AND HV MAINTAINED THIS MENTION IN
THE HWO. MORE SUN/COMPRESSIONAL HEATING AHEAD OF FRONT WILL ALLOW
FOR MUCH WARMER TEMPS ON FRIDAY AS THE REGION RETURNS INTO THE
WARM SECTOR. LOOK FOR HIGHS IN THE MID 70S TO LOW 80S...WITH SOME
MID 80S POSSIBLE ACROSS THE SOUTH IF CLEARING OCCURS A BIT QUICKER
THAN PRESENTLY MODELED.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 446 PM EDT TUE...
SFC CDFNT TO PUSH OFF THE CST AFT MDNGT FRI NGT...TO BE FOLLOWED
BY HI PRES FM THE WNW BUILDING OVR THE RGN THIS WKND. CONTG HI
CHC/LIKELY POPS FRI EVE...THEN TAPERING OFF W-E THROUGH LT FRI
NGT/EARLY SAT MRNG. XPCG CLRG ON SAT AS DRYING AIR FM THE WNW
SPREADS OVR THE RGN. THE HIGH MOVES OFF THE CST BY EARLY NEXT
WK...RESULTING IN WNDS BECOMING SSW...AND MOISTURE GRADUALLY
INCRSG. LO TEMPS FRI NGT FM THE M50S NW TO ARND 60F SE. HI TEMPS
SAT IN THE L/M60S AT THE CST...TO L70S INLAND. LO TEMPS SAT NGT FM
THE M40S NW TO L50S SE. HI TEMPS SUN NR 60F AT THE CST...TO 65 TO
70F ELSW. HI TEMPS MON/TUE FM THE M60S TO M70S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A BACKDOOR COLD FRONT IS SITUATED FROM NEAR THE ALBEMARLE SOUND
WESTWARD ACROSS NRN NC EARLY THIS AFTERNOON. STRATUS IS WIDESPREAD
ON THE COOL SIDE OF THE FRONT WITH OVC CIGS ~500FT. VSBY IS
AVERAGING 2-3SM NEAR THE COAST TO > 6SM INLAND. IFR CIGS SHOULD
PREVAIL THIS AFTERNOON AT ALL TERMINALS WITH THE EXCEPTION OF
ECG...WHICH COULD OCCASIONALLY SCATTER OUT IN CLOSER PROXIMITY TO
THE BOUNDARY. MOST OF THE AFTERNOON SHOULD BE RAIN-FREE. AN MCS OVER
WV COULD REACH CENTRAL VA EARLY THIS EVENING LIKELY IN THE FORM OF
SHRA WITH SOME EMBEDDED THUNDER POSSIBLE. OTHERWISE...THE BOUNDARY
AGAIN SINKS S OVERNIGHT. EXPECT CIGS AND VSBY TO LOWER
OVERNIGHT...WITH LIFR CONDITIONS LIKELY AT ALL SITES. SOME -RA IS
POSSIBLE OVERNIGHT...BUT THERE IS ENOUGH UNCERTAINTY IN TIMING AND
COVERAGE...SO OTHER THAN SOME -SHRA AT RIC THIS EVENING NO OTHER -RA
HAS BEEN INCLUDED. CIGS SHOULD SLOWLY LIFT THURSDAY MORNING WITH
MORE IMPROVEMENT DURING THE AFTERNOON AS THE BOUNDARY LIFTS BACK
THROUGH THE REGION AS A WARM FRONT. A COLD FRONT CROSSES THE REGION
FRIDAY AFTERNOON AND EVENING BRINGING SHRA/TSRA...ALONG WITH A
BREEZY SSW WIND AHEAD OF THE FRONT. HIGH PRESSURE RETURNS SATURDAY
AND SUNDAY AND MOVES OFFSHORE MONDAY.
&&
.MARINE...
SFC LOW PRESSURE WILL MOVE ACROSS THE WATERS INVOF A BACKDOOR COLD
FRONT...WHICH IS DROPPING DOWN ACROSS THE VA EASTERN SHORE AS OF
300 AM THIS MORNING. WINDS ARE GENERALLY LIGHT FROM THE S-SW SOUTH
OF THE FRONT...WITH BREEZY N-NE WINDS 10-20KT WITH GUSTS AROUND
25KT NORTH OF THE FRONT. AM ALREADY SEEING AN INCREASE IN WIND
SPEEDS IN CHES BAY NORTH OF TANGIER ISLAND AND ALONG THE ATLANTIC
COAST FROM FENWICK ISLAND TO PARRAMORE ISLAND. THE FRONT WILL
GRADUALLY DROP SWD THROUGH THE REST OF TODAY...STALLING ACROSS THE
CAROLINAS TONIGHT INTO THU. EXPECT NNE WINDS TO INCREASE OVER THE
WATERS THROUGH TODAY WITH A BRIEF REPRIEVE TONIGHT. SPEEDS WILL
GENERALLY BE 10-20KT OVER BAY/RIVERS/SOUND AND 15-25KT OVER THE
COASTAL WATERS. SEAS ARE ALSO EXPECTED TO BUILD FROM 2-3FT TO
5-7FT NORTH OF CAPE CHARLES LIGHT...3-4FT SOUTH. ONSHORE FLOW
PERSISTS ON THU WITH AN UPTICK IN WIND SPEEDS TO 10-15KT DURING
THE AFTN/EARLY EVENING. SEAS SUBSIDE BELOW 5FT IN SRN WATERS BY
THU AFTN...WHILE SEAS LINGER AROUND 4-5FT NORTH OF PARRAMORE
ISLAND UNTIL EARLY EVENING. SCA FLAGS FROM FENWICK ISLAND TO CAPE
CHARLES GO INTO EFFECT AT 600 AM THIS MORNING AND WILL MAINTAIN
THAT START TIME BASED ON CURRENT OBSERVATIONS.
THE STALLED FRONT LIFTS NWD AS A WARM FRONT THU NIGHT INTO EARLY FRI
AND WINDS BECOME SLY. SEAS 2-3FT...WAVES 1-2FT. SPEEDS BEGIN TO
INCREASE AROUND SUNRISE FRI MORNING AND WILL CONTINUE TO BE BREEZY
DURING THE DAY AHEAD OF AN APPROACHING COLD FRONT. SPEEDS WILL
AVERAGE 15-20KT (GUSTS UP TO 25KT OVER COASTAL WATERS). SEAS BUILD
TO 3-4FT AND MAY REACH UP TO 5FT NEAR BUOY 44009 BY LATE FRI
AFTN/EARLY EVENING. THE COLD FRONT CROSSES THE WATERS FRI NIGHT. THE
COOLER AIRMASS BEHIND THE FRONT DOES NOT ARRIVE UNTIL DURING THE DAY
ON SAT. A DAYTIME ARRIVAL OF COOLER AIR WILL DECREASE CHANCES FOR
POST-FRONTAL SCA WINDS. EXPECT NW WINDS ON SAT AOB 15KT...DECREASING
SAT NIGHT AS HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST AND
SETTLES OVER THE WATERS ON SUN/SUN NIGHT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THURSDAY FOR ANZ652-654.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ650.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAS/MAM
SHORT TERM...MAS/MAM
LONG TERM...ALB
AVIATION...AJZ
MARINE...ALB/BMD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
656 PM EDT WED APR 8 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 456 PM EDT WED APR 8 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW PAIR OF SHORTWAVES
RESPONSIBLE FOR THE LIGHT WINTRY MIX OF PCPN EARLIER TODAY NOW N AND
E OF THE FCST AREA. ANOTHER SHORTWAVE MOVING FROM MANITOBA INTO NRN
ONTARIO WON`T BE A FACTOR IN THE SHORT TERM WEATHER. FARTHER TO THE
NW AND ALSO TO THE SW ARE 2 SHORTWAVES THAT WILL PLAY A ROLE IN WHAT
WILL BECOME A QUICK HITTING SIGNIFICANT SPRING SNOWSTORM FOR
PORTIONS OF UPPER MI THU NIGHT. ONE WAVE IS DROPPING INTO NRN
MANITOBA AND THE SECOND WAVE IS OVER NV/UT. DETAILS ON THE HVY/WET
SNOW CAN BE FOUND IN THE LONG TERM PORTION OF THE DISCUSSION BELOW.
IN THE WAKE OF THE PCPN EARLIER TODAY...ABUNDANT CLOUD COVER
DOMINATES THE UPPER GREAT LAKES...THOUGH NOT ALL OF THE LOW-LEVEL
DRY AIR HAS BEEN ERODED...AND THERE IS STILL A FEED OF DRIER AIR AT
THE LOW LEVELS FROM THE E. THIS HAS RESULTED IN SOME BREAKS
DEVELOPING IN THE CLOUD COVER OVER UPPER MI IN THE LAST FEW HRS.
WHERE SOME SUN HAS APPEARED...TEMPS HAVE RISEN INTO THE MID AND
UPPER 40S.
SHORTWAVE OVER NV/UT WILL SHIFT E AND RESULT IN SFC LOW PRES
DEVELOPING OVER KS TONIGHT. FARTHER DOWNSTREAM...WATER VAPOR IMAGERY
SUGGESTS MORE SUBTLE SHORTWAVE ENERGY LIFTING OUT OVER THE PLAINS.
INCREASING WAA/ISENTROPIC ASCENT REGIME DOWNSTREAM OF THE MAIN
SHORTWAVE TROF AND ENHANCED BY THE SUBTLE LEAD ENERGY WILL LEAD TO A
AN AREA OF RAIN DEVELOPING AND SPREADING/EXPANDING NE INTO UPPER MI
LATE TONIGHT INTO THU MORNING. BASED ON NRN EDGE OF THE POOL OF
MUCAPE THAT LIFTS N INTO WI...NOT OUT OF THE QUESTION THAT THERE
COULD BE FEW RUMBLES OF THUNDER. WHETHER TEMPS WILL BE BLO FREEZING
WHEN PCPN BEGINS IS UNCERTAIN. USING MODEL CONSENSUS DIURNAL TEMP
CURVE SUGGESTS THERE WILL BE AREAS WHERE TEMPS MAY BE JUST BLO
FREEZING LATE TONIGHT/EARLY THU MORNING. HOWEVER...IF TEMPS DON`T
FALL MUCH THIS EVENING...-FZRA POTENTIAL WILL BE DIMINISHED. AT THIS
TIME...NOT EXPECTING SUFFICIENT ICE PROBLEMS ON ROADWAYS TO WARRANT
ADVY ISSUANCE...BUT WILL CONTINUE TO HIGHLIGHT POTENTIAL OF SOME ICY
CONDITIONS ON UNTREATED SURFACES LATE TONIGHT THRU MID MORNING THU.
AFTER THE INITIAL SURGE OF WAA/ISENTROPIC ASCENT PCPN THAT SWEEPS NE
LATE TONIGHT/THU MORNING...WILL PROBABLY SEE -RA DIMINISH OR BECOME
MORE SCATTERED FOR A TIME LATE MORNING THRU MID AFTN OR SO AS WE
AWAIT THE MAIN SHORTWAVE/STRONG DYNAMICS THAT WILL LIFT INTO THE
UPPER LAKES THU NIGHT. PCPN IS LESS LIKELY TO DIMINISH OVER THE W
WHERE 850MB TROF WILL EXTEND NE FROM THE APPROACHING LOW ACROSS WRN
UPPER MI/WRN LAKE SUPERIOR.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 456 PM EDT WED APR 8 2015
COMPLEX FORECAST FRONT LOADED IN FIRST PERIOD OF LONG TERM. HIGH
IMPACT WEATHER EXPECTED IN FORM OF RAIN CHANGING TO HEAVY SNOW.
MAIN FACTORS COMING INTO FOCUS FOR THURSDAY NIGHT WEATHER. FIRST
ALOFT...UPPER TROUGH OVER THE INTERIOR WESTERN CONUS THIS MORNING
MOVES TO UPPER MISSISSIPPI RIVER VALLEY BY THURSDAY EVENING WHILE
SHORTWAVE TROUGH DIGGING OVER NORTHERN SASKATCHEWAN THIS AFTN MOVES
TO AXIS FM NORTHERN ONTARIO TO SOUTHERN MANITOBA. MAIN JET STREAK
LIFTS OVER NORTHERN ONTARIO INTO QUEBEC ON THURSDAY EVENING WHILE
ANOTHER JET WILL BE IN PROCESS OF EXITING TOWARD GREAT LAKES. AS THE
PLAINS JET ARRIVES OVER THE GREAT LAKES THURSDAY EVENING...LEAD
SHORTWAVE TROUGH IS FORECAST TO BECOME MORE NEGATIVELY TILTED AS IT
LIFTS OVER THE UPPER GREAT LAKES. FOR MOST PART...LEAD WAVE DRIVES
STRENGTH AND TRACK OF H85-H7 TROUGH AND PRIMARY SFC LOW...WHICH
TRACKS FM IOWA AT 00Z FRIDAY TO NORTHERN LK MICHIGAN/NORTHERN LOWER
MICHIGAN BY 06Z FRIDAY AND TO EAST OF SAULT STE MARIE BY 12Z FRIDAY.
MODELS CONTINUE TO DIFFER ON WESTWARD EXTENT OF SFC LOW WHICH
AFFECTS WHERE SWATH OF HEAVY QPF WELL OVER 1 INCH OCCURS ROUGHLY 00Z-
09Z ON FRIDAY. GIVEN VERY STRONG LIFT FM COUPLED JET STRUCTURE AND
ENHANCED DIVERGENCE ALOFT AND PERSISTENT STRONG MID-LEVEL FGEN ALONG
WITH COPIOUS DEEP MOISTURE THAT SHOULD BE ABLE TO TRANSLATE INTO THE
DEEPENING SYSTEM AS MAIN INFLOW FOR TSRA SHOULD STAY FAR ENOUGH
SOUTHEAST OF UPR MICHIGAN...TEND TO BELIEVE WETTER IDEAS OFFERED UP
BY NAM/GFS SHOWING WELL OVER 1 INCH OF QPF. THOUGH ECMWF REMAINS
DRIER...IT HAS SHOWN NOTEABLE TREND TOWARD STRONGER SYSTEM THE LAST
DAY...SO THAT IS ENCOURAGING AT LEAST FROM THE FORECAST STANDPOINT.
RUNNING WITH THE STRONGER/WETTER IDEA...MAIN STICKING POINT IS HOW
QUICK THE RAIN CHANGES TO SNOW ON THURSDAY NIGHT. THE EARLIER THAT
SWITCHOVER OCCURS...THE MORE THAT HEAVY QPF WILL GO TOWARD WET HEAVY
SNOW ACCUMULATION. NAM SOUNDINGS SHOW WARM LAYER BTWN 900MB-800MB
VCNTY OF L`ANSE TO WATERSMEET AT 00Z...THEN TO CRYSTAL FALLS AND
MARQUETTE/HARVEY BY 03Z...BEFORE PUSHING THIS ON THE MUNISING AND
ESCANABA BY 06Z. GFS AND GEM-REGIONAL ARE FARTHER WEST WITH WARM
LAYER ALOFT...THOUGH THEY BOTH TRENDED A BIT EAST WITH TRACK OF SFC
LOW ON THE 12Z RUNS. EXPECT HEAVY WET SNOW TO IMPACT PARTS OF
WESTERN HALF OF UPR MICHIGAN. RETREATING WARM LAYER TO START COULD
ALSO RESULT IN SLEET OF FZRA BEFORE CHANGE TO SNOW OCCURS.
DECIDED TO ISSUE A WINTER STORM WATCH FOR WESTERN UPR MICHIGAN AS
THERE SHOULD BE A NARROW STRIPE OF POSSIBLE VERY HEAVY WET SNOW
THURSDAY NIGHT. GIVEN THE FORCING AND MOISTURE...LOCALIZED AMOUNTS
OVER 8 INCHES SEEM POSSIBLE. MAIN QUANDARY WAS HOW FAR WEST AND EAST
TO PUSH THE WATCH. LEANED A BIT TOWARD THE FARTHER EAST WARM LAYER
IDEA WHICH RESULTED IN BRINGING THE WATCH AS FAR EAST AS MARQUETTE
COUNTY. GIVEN DECENT CHANCE THAT PRECIP STAYS MAINLY RAIN WELL INTO
THE EVENING FOR DICKINSON COUNTY LEFT THEM OUT FOR NOW...THOUGH
COULD SEE NEED FOR ADVY FOR EVENTUALLY SLOPPY INCH OR TWO OF SNOW.
CORRIDER OF HEAVY SNOW LIKELY WILL NOT MAKE IT AS FAR WEST AS IWD
THOUGH LATEST HPC/WWD GRAPHICS STILL HIT FAR WEST FOR DECENT AMOUNT
OF SNOW...BUT SINCE EASTERN PORTIONS OF GOGEBIC COUNTY INTO
ONTONAGON COUNTY WOULD BE IMPACTED BY THE HEAVY SNOW WITH LATEST
THINKING...INCLUDED GOGEBIC AS WELL. ESSENTIALLY SINCE THIS EVENT
COULD BE VERY HIGH IMPACT DECIDED TO GO THIS ROUTE INSTEAD OF HAVING
AN SPS OUT ONLY. WILL TRY TO CONVEY THE UNCERTAINTY DUE TO BOTH
LOCATION OF HEAVIER SNOW AND PTYPE IN THE WSW STATEMENT. COORD WITH
DLH AND GRB ON SNOW AMOUNTS/HEADLINE TIMING.
LOW PRESSURE EXITS OVER EASTERN CANADA FRIDAY INTO FRIDAY NIGHT.
LINGERING LOW-LEVEL MOISTURE/THERMAL TROUGHING AND ADDITIONAL
FORCING FM THE NORTHERN STREAM WAVE DROPPING OVER THE AREA SUPPORTS
CHANCE POPS FOR SNOW ON FRIDAY THOUGH MOST OF THE BIGGER SNOW WILL
BE DONE BY DAYBREAK FRIDAY. KEPT WITH TEMPS MAINLY IN THE 30S ON
FRIDAY. BREEZY CONDITIONS TOO...ESPECIALLY NEAR LK SUPERIOR IN THE
MORNING HOURS. SFC RIDGE CROSSES FRIDAY NIGHT AND TEMPS COULD DIP
INTO THE TEENS. EXPECT THIS TO BE THE LAST NIGHT THROUGH THE LONG
TERM WHERE TEMPS DROP BLO FREEZING.
TEMPS THIS WEEKEND LOOKS WARMER...MUCH WARMER. HIGH CLOUDS INCREASE
LATE SATURDAY AND SATURDAY NIGHT AHEAD OF LOW PRESSURE TROUGH THAT
MOVES FM SCNTRL CANADA TO NORTHERN PLAINS ON SUNDAY. MIXING HEIGHTS
UP TO H85 WITH SW WINDS SUPPORT READINGS WELL INTO THE 50S. COOLEST
TEMPS OVER EAST CWA WITH FLOW COMING OFF LK MICHIGAN. SOME LGT RAIN
MAY DEVELOP AHEAD OF THE TROUGH ON SUNDAY AS GFS/ECMWF HAVE BEEN
SHOWING FOR A WHILE NOW. EVEN SO...WARMER TEMPS ALOFT AND WARMER MIN
TEMPS ON SATURDAY NIGHT ALLOW MANY AREAS TO REACH 60 DEGREES. SO ANY
SNOW THAT DOES OCCUR THURSDAY NIGHT INTO FRIDAY SHOULD QUICKLY MELT
THIS WEEKEND.
FURTHER...ONCE THE TEMPS RISE ABOVE FREEZING ON SATURDAY THEY SHOULD
REMAIN ABOVE FREEZING THROUGH MUCH OF NEXT WEEK SO WE SHOULD ALSO
BEGIN TO MELT GOOD PORTION OF THE SNOWPACK THAT REMAINS OVER MAINLY
NORTHERN UPPER MICHIGAN. SHOULD SEE AREA RIVERS AND STREAMS BEGIN TO
RESPOND WITH THE SNOWMELT AND RUNOFF. ADDITIONAL RAINFALL POSSIBLE
TUESDAY INTO WEDNESDAY AS A LOW PRESSURE SYSTEM AND WARM FRONT MOVE
TOWARD THE NORTHERN PLAINS AND UPPER GREAT LAKES. ANY RAINFALL FM
THIS SYSTEM WOULD ONLY ADD TO THE RUNOFF. SEEMS THAT AFTER THIS
WINTRY SYSTEM WE MIGHT JUST SHIFT INTO THE MAIN SNOWMELT HYDROLOGY
PERIOD OF THE SPRING.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 656 PM EDT WED APR 8 2015
GUIDANCE IS STRONGLY POINTING TOWARD DETERIORATING CONDITIONS THIS
EVENING AND WILL GO WITH THIS TREND AT ALL SITES. AS MOISTURE AND
PCPN SPREAD N LATE TONIGHT/EARLY THU...EXPECT CONDITIONS TO FALL TO
IFR AT ALL TERMINALS. PCPN MAY BEGIN AS -FZRA FOR 2-3HRS AT
KCMX/KSAW...BUT WILL CHANGE TO -RA AS TEMPS RISE DURING THE MORNING.
KSAW IS LIKELY TO FALL TO LIFR BY MID MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 456 PM EDT WED APR 8 2015
HIGH PRES MOVING E ACROSS QUEBEC AND LOW PRES DEVELOPING OVER THE
CNTRL/SRN PLAINS WILL KEEP LAKE SUPERIOR UNDER GENERAL E TO NE WINDS
OF 10-20KT THRU EARLY THU AFTN. AS THE LOW PRES TRACKS NE ACROSS
NORTHERN LAKE MI THU EVENING AND INTO ONTARIO FRI MORNING...WINDS
WILL BACK TO THE NW. OVER THE CNTRL PART OF LAKE SUPERIOR...THE WIND
WILL ALSO INCREASE TO 20-30KT...AND OVER ERN LAKE SUPERIOR N TO NW
GALES WILL DEVELOP BY FRI MORNING. WINDS WILL THEN DIMINISH W TO E
FRI AFTN THRU FRI NIGHT AS HIGH PRES BUILDS ACROSS THE MISSISSIPPI
VALLEY. LIGHT WINDS UNDER 20KT ARE EXPECTED SAT AS THE HIGH PRES
RIDGE PASSES ACROSS THE WRN GREAT LAKES. AS THE RIDGE SHIFTS E AND A
LOW PRES TROF MOVES E ACROSS THE NRN PLAINS...WINDS WILL THEN
INCREASE SAT NIGHT/SUN...PROBABLY REACHING 15-25KT OR MORE OVER AT
LEAST THE E HALF OF LAKE SUPERIOR ON SUN. THE TROF WILL CROSS THE
UPPER GREAT LAKES SUN NIGHT...BRINGING A WIND SHIFT TO THE W.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY MORNING
FOR MIZ001>005-009-010-084.
LAKE SUPERIOR...
GALE WATCH FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON FOR
LSZ266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
456 PM EDT WED APR 8 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 456 PM EDT WED APR 8 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW PAIR OF SHORTWAVES
RESPONSIBLE FOR THE LIGHT WINTRY MIX OF PCPN EARLIER TODAY NOW N AND
E OF THE FCST AREA. ANOTHER SHORTWAVE MOVING FROM MANITOBA INTO NRN
ONTARIO WON`T BE A FACTOR IN THE SHORT TERM WEATHER. FARTHER TO THE
NW AND ALSO TO THE SW ARE 2 SHORTWAVES THAT WILL PLAY A ROLE IN WHAT
WILL BECOME A QUICK HITTING SIGNIFICANT SPRING SNOWSTORM FOR
PORTIONS OF UPPER MI THU NIGHT. ONE WAVE IS DROPPING INTO NRN
MANITOBA AND THE SECOND WAVE IS OVER NV/UT. DETAILS ON THE HVY/WET
SNOW CAN BE FOUND IN THE LONG TERM PORTION OF THE DISCUSSION BELOW.
IN THE WAKE OF THE PCPN EARLIER TODAY...ABUNDANT CLOUD COVER
DOMINATES THE UPPER GREAT LAKES...THOUGH NOT ALL OF THE LOW-LEVEL
DRY AIR HAS BEEN ERODED...AND THERE IS STILL A FEED OF DRIER AIR AT
THE LOW LEVELS FROM THE E. THIS HAS RESULTED IN SOME BREAKS
DEVELOPING IN THE CLOUD COVER OVER UPPER MI IN THE LAST FEW HRS.
WHERE SOME SUN HAS APPEARED...TEMPS HAVE RISEN INTO THE MID AND
UPPER 40S.
SHORTWAVE OVER NV/UT WILL SHIFT E AND RESULT IN SFC LOW PRES
DEVELOPING OVER KS TONIGHT. FARTHER DOWNSTREAM...WATER VAPOR IMAGERY
SUGGESTS MORE SUBTLE SHORTWAVE ENERGY LIFTING OUT OVER THE PLAINS.
INCREASING WAA/ISENTROPIC ASCENT REGIME DOWNSTREAM OF THE MAIN
SHORTWAVE TROF AND ENHANCED BY THE SUBTLE LEAD ENERGY WILL LEAD TO A
AN AREA OF RAIN DEVELOPING AND SPREADING/EXPANDING NE INTO UPPER MI
LATE TONIGHT INTO THU MORNING. BASED ON NRN EDGE OF THE POOL OF
MUCAPE THAT LIFTS N INTO WI...NOT OUT OF THE QUESTION THAT THERE
COULD BE FEW RUMBLES OF THUNDER. WHETHER TEMPS WILL BE BLO FREEZING
WHEN PCPN BEGINS IS UNCERTAIN. USING MODEL CONSENSUS DIURNAL TEMP
CURVE SUGGESTS THERE WILL BE AREAS WHERE TEMPS MAY BE JUST BLO
FREEZING LATE TONIGHT/EARLY THU MORNING. HOWEVER...IF TEMPS DON`T
FALL MUCH THIS EVENING...-FZRA POTENTIAL WILL BE DIMINISHED. AT THIS
TIME...NOT EXPECTING SUFFICIENT ICE PROBLEMS ON ROADWAYS TO WARRANT
ADVY ISSUANCE...BUT WILL CONTINUE TO HIGHLIGHT POTENTIAL OF SOME ICY
CONDITIONS ON UNTREATED SURFACES LATE TONIGHT THRU MID MORNING THU.
AFTER THE INITIAL SURGE OF WAA/ISENTROPIC ASCENT PCPN THAT SWEEPS NE
LATE TONIGHT/THU MORNING...WILL PROBABLY SEE -RA DIMINISH OR BECOME
MORE SCATTERED FOR A TIME LATE MORNING THRU MID AFTN OR SO AS WE
AWAIT THE MAIN SHORTWAVE/STRONG DYNAMICS THAT WILL LIFT INTO THE
UPPER LAKES THU NIGHT. PCPN IS LESS LIKELY TO DIMINISH OVER THE W
WHERE 850MB TROF WILL EXTEND NE FROM THE APPROACHING LOW ACROSS WRN
UPPER MI/WRN LAKE SUPERIOR.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 456 PM EDT WED APR 8 2015
COMPLEX FORECAST FRONT LOADED IN FIRST PERIOD OF LONG TERM. HIGH
IMPACT WEATHER EXPECTED IN FORM OF RAIN CHANGING TO HEAVY SNOW.
MAIN FACTORS COMING INTO FOCUS FOR THURSDAY NIGHT WEATHER. FIRST
ALOFT...UPPER TROUGH OVER THE INTERIOR WESTERN CONUS THIS MORNING
MOVES TO UPPER MISSISSIPPI RIVER VALLEY BY THURSDAY EVENING WHILE
SHORTWAVE TROUGH DIGGING OVER NORTHERN SASKATCHEWAN THIS AFTN MOVES
TO AXIS FM NORTHERN ONTARIO TO SOUTHERN MANITOBA. MAIN JET STREAK
LIFTS OVER NORTHERN ONTARIO INTO QUEBEC ON THURSDAY EVENING WHILE
ANOTHER JET WILL BE IN PROCESS OF EXITING TOWARD GREAT LAKES. AS THE
PLAINS JET ARRIVES OVER THE GREAT LAKES THURSDAY EVENING...LEAD
SHORTWAVE TROUGH IS FORECAST TO BECOME MORE NEGATIVELY TILTED AS IT
LIFTS OVER THE UPPER GREAT LAKES. FOR MOST PART...LEAD WAVE DRIVES
STRENGTH AND TRACK OF H85-H7 TROUGH AND PRIMARY SFC LOW...WHICH
TRACKS FM IOWA AT 00Z FRIDAY TO NORTHERN LK MICHIGAN/NORTHERN LOWER
MICHIGAN BY 06Z FRIDAY AND TO EAST OF SAULT STE MARIE BY 12Z FRIDAY.
MODELS CONTINUE TO DIFFER ON WESTWARD EXTENT OF SFC LOW WHICH
AFFECTS WHERE SWATH OF HEAVY QPF WELL OVER 1 INCH OCCURS ROUGHLY 00Z-
09Z ON FRIDAY. GIVEN VERY STRONG LIFT FM COUPLED JET STRUCTURE AND
ENHANCED DIVERGENCE ALOFT AND PERSISTENT STRONG MID-LEVEL FGEN ALONG
WITH COPIOUS DEEP MOISTURE THAT SHOULD BE ABLE TO TRANSLATE INTO THE
DEEPENING SYSTEM AS MAIN INFLOW FOR TSRA SHOULD STAY FAR ENOUGH
SOUTHEAST OF UPR MICHIGAN...TEND TO BELIEVE WETTER IDEAS OFFERED UP
BY NAM/GFS SHOWING WELL OVER 1 INCH OF QPF. THOUGH ECMWF REMAINS
DRIER...IT HAS SHOWN NOTEABLE TREND TOWARD STRONGER SYSTEM THE LAST
DAY...SO THAT IS ENCOURAGING AT LEAST FROM THE FORECAST STANDPOINT.
RUNNING WITH THE STRONGER/WETTER IDEA...MAIN STICKING POINT IS HOW
QUICK THE RAIN CHANGES TO SNOW ON THURSDAY NIGHT. THE EARLIER THAT
SWITCHOVER OCCURS...THE MORE THAT HEAVY QPF WILL GO TOWARD WET HEAVY
SNOW ACCUMULATION. NAM SOUNDINGS SHOW WARM LAYER BTWN 900MB-800MB
VCNTY OF L`ANSE TO WATERSMEET AT 00Z...THEN TO CRYSTAL FALLS AND
MARQUETTE/HARVEY BY 03Z...BEFORE PUSHING THIS ON THE MUNISING AND
ESCANABA BY 06Z. GFS AND GEM-REGIONAL ARE FARTHER WEST WITH WARM
LAYER ALOFT...THOUGH THEY BOTH TRENDED A BIT EAST WITH TRACK OF SFC
LOW ON THE 12Z RUNS. EXPECT HEAVY WET SNOW TO IMPACT PARTS OF
WESTERN HALF OF UPR MICHIGAN. RETREATING WARM LAYER TO START COULD
ALSO RESULT IN SLEET OF FZRA BEFORE CHANGE TO SNOW OCCURS.
DECIDED TO ISSUE A WINTER STORM WATCH FOR WESTERN UPR MICHIGAN AS
THERE SHOULD BE A NARROW STRIPE OF POSSIBLE VERY HEAVY WET SNOW
THURSDAY NIGHT. GIVEN THE FORCING AND MOISTURE...LOCALIZED AMOUNTS
OVER 8 INCHES SEEM POSSIBLE. MAIN QUANDARY WAS HOW FAR WEST AND EAST
TO PUSH THE WATCH. LEANED A BIT TOWARD THE FARTHER EAST WARM LAYER
IDEA WHICH RESULTED IN BRINGING THE WATCH AS FAR EAST AS MARQUETTE
COUNTY. GIVEN DECENT CHANCE THAT PRECIP STAYS MAINLY RAIN WELL INTO
THE EVENING FOR DICKINSON COUNTY LEFT THEM OUT FOR NOW...THOUGH
COULD SEE NEED FOR ADVY FOR EVENTUALLY SLOPPY INCH OR TWO OF SNOW.
CORRIDER OF HEAVY SNOW LIKELY WILL NOT MAKE IT AS FAR WEST AS IWD
THOUGH LATEST HPC/WWD GRAPHICS STILL HIT FAR WEST FOR DECENT AMOUNT
OF SNOW...BUT SINCE EASTERN PORTIONS OF GOGEBIC COUNTY INTO
ONTONAGON COUNTY WOULD BE IMPACTED BY THE HEAVY SNOW WITH LATEST
THINKING...INCLUDED GOGEBIC AS WELL. ESSENTIALLY SINCE THIS EVENT
COULD BE VERY HIGH IMPACT DECIDED TO GO THIS ROUTE INSTEAD OF HAVING
AN SPS OUT ONLY. WILL TRY TO CONVEY THE UNCERTAINTY DUE TO BOTH
LOCATION OF HEAVIER SNOW AND PTYPE IN THE WSW STATEMENT. COORD WITH
DLH AND GRB ON SNOW AMOUNTS/HEADLINE TIMING.
LOW PRESSURE EXITS OVER EASTERN CANADA FRIDAY INTO FRIDAY NIGHT.
LINGERING LOW-LEVEL MOISTURE/THERMAL TROUGHING AND ADDITIONAL
FORCING FM THE NORTHERN STREAM WAVE DROPPING OVER THE AREA SUPPORTS
CHANCE POPS FOR SNOW ON FRIDAY THOUGH MOST OF THE BIGGER SNOW WILL
BE DONE BY DAYBREAK FRIDAY. KEPT WITH TEMPS MAINLY IN THE 30S ON
FRIDAY. BREEZY CONDITIONS TOO...ESPECIALLY NEAR LK SUPERIOR IN THE
MORNING HOURS. SFC RIDGE CROSSES FRIDAY NIGHT AND TEMPS COULD DIP
INTO THE TEENS. EXPECT THIS TO BE THE LAST NIGHT THROUGH THE LONG
TERM WHERE TEMPS DROP BLO FREEZING.
TEMPS THIS WEEKEND LOOKS WARMER...MUCH WARMER. HIGH CLOUDS INCREASE
LATE SATURDAY AND SATURDAY NIGHT AHEAD OF LOW PRESSURE TROUGH THAT
MOVES FM SCNTRL CANADA TO NORTHERN PLAINS ON SUNDAY. MIXING HEIGHTS
UP TO H85 WITH SW WINDS SUPPORT READINGS WELL INTO THE 50S. COOLEST
TEMPS OVER EAST CWA WITH FLOW COMING OFF LK MICHIGAN. SOME LGT RAIN
MAY DEVELOP AHEAD OF THE TROUGH ON SUNDAY AS GFS/ECMWF HAVE BEEN
SHOWING FOR A WHILE NOW. EVEN SO...WARMER TEMPS ALOFT AND WARMER MIN
TEMPS ON SATURDAY NIGHT ALLOW MANY AREAS TO REACH 60 DEGREES. SO ANY
SNOW THAT DOES OCCUR THURSDAY NIGHT INTO FRIDAY SHOULD QUICKLY MELT
THIS WEEKEND.
FURTHER...ONCE THE TEMPS RISE ABOVE FREEZING ON SATURDAY THEY SHOULD
REMAIN ABOVE FREEZING THROUGH MUCH OF NEXT WEEK SO WE SHOULD ALSO
BEGIN TO MELT GOOD PORTION OF THE SNOWPACK THAT REMAINS OVER MAINLY
NORTHERN UPPER MICHIGAN. SHOULD SEE AREA RIVERS AND STREAMS BEGIN TO
RESPOND WITH THE SNOWMELT AND RUNOFF. ADDITIONAL RAINFALL POSSIBLE
TUESDAY INTO WEDNESDAY AS A LOW PRESSURE SYSTEM AND WARM FRONT MOVE
TOWARD THE NORTHERN PLAINS AND UPPER GREAT LAKES. ANY RAINFALL FM
THIS SYSTEM WOULD ONLY ADD TO THE RUNOFF. SEEMS THAT AFTER THIS
WINTRY SYSTEM WE MIGHT JUST SHIFT INTO THE MAIN SNOWMELT HYDROLOGY
PERIOD OF THE SPRING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 139 PM EDT WED APR 8 2015
MVFR CONDITIONS SHOULD BE THE RULE AT KIWD/KCMX/KSAW INTO THIS
EVENING. HOWEVER...WITH A FEED OF DRY AIR FROM THE E BASED ON SFC
OBS...TERMINALS MAY IMPROVE TO VFR AT SOME POINT THIS AFTN. BEING
CLOSER TO THE DRIER AIR...KSAW HAS THE BEST OPPORTUNITY OF VFR.
GUIDANCE IS STRONGLY POINTING TOWARD DETERIORATING CONDITIONS THIS
EVENING...BUT BELIEVE DRY AIR MAY CONTINUE TO HAVE AN INFLUENCE
UNDER AN E TO ESE FLOW. THUS...IF VFR CONDITIONS DEVELOP THIS
AFTN...VFR MAY LINGER THRU THE EVENING. AS MOISTURE AND PCPN SPREAD
N LATE TONIGHT/EARLY THU...EXPECT CONDITIONS TO FALL TO IFR AT ALL
TERMINALS. PCPN MAY BEGIN AS -FZRA FOR 2-3HRS AT KCMX/KSAW...BUT
WILL CHANGE TO -RA AS TEMPS RISE DURING THE MORNING. KSAW IS LIKELY
TO FALL TO LIFR BY MID MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 456 PM EDT WED APR 8 2015
HIGH PRES MOVING E ACROSS QUEBEC AND LOW PRES DEVELOPING OVER THE
CNTRL/SRN PLAINS WILL KEEP LAKE SUPERIOR UNDER GENERAL E TO NE WINDS
OF 10-20KT THRU EARLY THU AFTN. AS THE LOW PRES TRACKS NE ACROSS
NORTHERN LAKE MI THU EVENING AND INTO ONTARIO FRI MORNING...WINDS
WILL BACK TO THE NW. OVER THE CNTRL PART OF LAKE SUPERIOR...THE WIND
WILL ALSO INCREASE TO 20-30KT...AND OVER ERN LAKE SUPERIOR N TO NW
GALES WILL DEVELOP BY FRI MORNING. WINDS WILL THEN DIMINISH W TO E
FRI AFTN THRU FRI NIGHT AS HIGH PRES BUILDS ACROSS THE MISSISSIPPI
VALLEY. LIGHT WINDS UNDER 20KT ARE EXPECTED SAT AS THE HIGH PRES
RIDGE PASSES ACROSS THE WRN GREAT LAKES. AS THE RIDGE SHIFTS E AND A
LOW PRES TROF MOVES E ACROSS THE NRN PLAINS...WINDS WILL THEN
INCREASE SAT NIGHT/SUN...PROBABLY REACHING 15-25KT OR MORE OVER AT
LEAST THE E HALF OF LAKE SUPERIOR ON SUN. THE TROF WILL CROSS THE
UPPER GREAT LAKES SUN NIGHT...BRINGING A WIND SHIFT TO THE W.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY MORNING
FOR MIZ001>005-009-010-084.
LAKE SUPERIOR...
GALE WATCH FROM FRIDAY MORNING THROUGH FRIDAY AFTERNOON FOR
LSZ266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
315 PM CDT WED APR 8 2015
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 315 PM CDT WED APR 8 2015
PRIMARY FORECAST CONCERNS ARE IN REGARDS TO CONVECTION TONIGHT
AND ALSO SHOWERS ON THURSDAY.
SOME STORMS DID OCCUR WITH SMALL HAIL FROM NORTH OF LINCOLN TOWARD
OMAHA EARLY THIS MORNING. STORMS REALLY DID NOT GET GOING STRONG TO
SEVERE UNTIL THEY WERE IN THE DMX FORECAST AREA. 500 MB CHART FROM
12Z SHOWED MAIN TROUGH STILL WELL OFF TO THE WEST. HEIGHT FALLS UP
TO AROUND 100 METERS WERE BACK OVER UTAH AT 12Z...BUT AS OF EARLY
AFTERNOON HAD PUSHED INTO PARTS OF WYOMING AND COLORADO.
GENERALLY EXPECT PCPN TO INCREASE IN COVERAGE TONIGHT...WITH
HEAVIEST PCPN AFTER ABOUT 11 PM. RECENT HRRR MODEL RUNS SUGGEST SOME
STRONG STORMS MAY FORM EARLY EVENING NEAR THE MISSOURI BORDER AREA.
OTHERWISE...MODELS TRENDS SHOWED LOW LEVEL JET SHOULD INCREASE
WITH UP TO 50 KNOTS AT 850 MB BY LATE EVENING. THIS SHOULD HELP
BRING AN INCREASE IN TSTMS OVER EASTERN NEBRASKA BY MIDNIGHT OR
SO. 12Z NAM FORECAST SOUNDINGS SHOWED UP TO AROUND 2000 J/KG OR
MORE OF ELEVATED CAPE AVAILABLE WITH 0-6 KM BULK SHEAR ADEQUATE
FOR ROTATING ELEVATED STORMS. THESE SHOULD BRING A RISK OF HAIL
MAINLY FROM 05Z TO 10Z...AND A FEW STORMS MAY BE SEVERE. THERE
COULD ALSO BE SOME LOCALLY HEAVY RAIN.
SHORTWAVE TO THE WEST WILL MOVE THROUGH THE AREA THURSDAY...WITH
HEAVIEST RAIN AMOUNTS ACROSS THE NORTHERN PARTS OF THE FORECAST
AREA NEAR DEFORMATION ZONE. WINDS WILL ALSO INCREASE AS SURFACE
LOW TRACKS EAST/NORTHEAST ACROSS IOWA DURING THE DAY AND THE
PRESSURE GRADIENT IN OUR AREA INCREASES. SPEEDS OF 20 TO 30 MPH
WITH GUSTS AROUND 40 MPH OR MORE SHOULD BE COMMON. DROPPED
FORECAST HIGHS JUST A BIT...WITH MOSTLY 50S EXPECTED THURSDAY.
PCPN WILL END BY THURSDAY EVENING WITH CLOUDS DECREASING THURSDAY
NIGHT. HIGH PRESSURE AT THE SURFACE BUILDS IN FOR THURSDAY NIGHT
AND FRIDAY. SOUTHERLY FLOW IS FORECAST TO INCREASE FRIDAY NIGHT...
MOSTLY TO OUR WEST...SO NO PCPN IS EXPECTED LOCALLY FRIDAY NIGHT.
WILL INCLUDE A SLIGHT CHANCE TSTMS FOR MAINLY OUR WESTERN ZONES
SATURDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 315 PM CDT WED APR 8 2015
WILL NEED TO INCLUDE A CHANCE OF SHOWERS AND TSTMS FOR MUCH OF THE
EXTENDED FORECAST PERIOD. HIGHEST CHANCES AND HEAVIEST AMOUNTS
LIKELY AS SHORTWAVE MOVES OUT ACROSS THE CENTRAL PLAINS MONDAY NIGHT
INTO TUESDAY. HIGHS SHOULD BE MOSTLY IN THE 70S THIS PERIOD...BUT
SOME UPPER 60S POSSIBLE ON MONDAY. LOWS GENERALLY 40S TO LOWER 50S.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1251 PM CDT WED APR 8 2015
WIDESPREAD IFR/LIFR CONDITIONS REMAIN IN PLACE ACROSS ERN NEB
THIS AFTN...AND SEE LITTLE CHANCE FOR ANY IMPROVING CONDITIONS
THRU THE REMAINDER OF THE FCST PD. OTHER ISSUE TO CONTEND WITH IS
POSSIBLE -TSRA ACTIVITY AT KOMA/KLNK BEGINNING LATER THIS EVENING
THEN THRU EARLY THURSDAY MORNING. CONVECTION EXPECTED TO DEVELOP
ALONG A FRONTAL BNDRY OVER ERN KS...THE GRADUALLY LIFT INTO ERN
NEB DURING THE EVENING HOURS. THE -TSRA THOUGH MAY BE ISOLATED IN
NATURE SO OPTED TO JUST GO WITH PROB30 GROUPS FOR NOW.
ALSO...CANNOT DISCOUNT THAT A FEW STORMS MAY PRODUCE NEAR SEVERE
HAIL THIS EVENING. COLD FRONT RUSHES IN THEN LATE THURSDAY MORNING
WITH WIND SHIFT TO THE NW AT ALL TERMINALS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEE
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
103 PM CDT WED APR 8 2015
.SYNOPSIS...
ISSUED AT 342 AM CDT WED APR 8 2015
H5 ANALYSIS FROM EARLIER THIS EVENING HAD A CLOSED LOW OVER NRN
CALIFORNIA WITH A TROUGH OF LOW PRESSURE EXTENDING SWD INTO SO
CALIFORNIA. SWLY FLOW ALOFT EXTENDED FROM THE SWRN CONUS NEWD INTO
THE ROCKIES AND PLAINS STATES. WV IMAGERY TONIGHT HAS THE BULK OF
MID AND UPPER LEVEL MOISTURE WITH THIS FEATURE ACROSS MEXICO AND
TEXAS. FURTHER NORTH...MAINLY DRY MID AND UPPER LEVELS WERE
NOTED...HOWEVER A SMALL DISTURBANCE...HAS SPREAD MID LEVEL CLOUDS
AND SHOWERS TO THE NORTHWESTERN CWA TONIGHT...WITH AN OCCASIONAL
LIGHTNING STRIKE NOTED. FOR THE REMAINDER OF THE FORECAST AREA...A
MOIST BOUNDARY LAYER AND EASTERLY WINDS...HAS LED TO ANOTHER NIGHT
OF LOW CLOUDS...FOG AND DRIZZLE. AT THE SURFACE...A STATIONARY
FRONT EXTENDED FROM AROUND COLORADO SPRINGS...SEWD TO THE KS/OK
BORDER. NORTH OF THE FRONT...EASTERLY WINDS AND MOSTLY CLOUDY
SKIES WERE PRESENT ACROSS ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA. AS OF 3 AM CDT...TEMPERATURES RANGED FROM 39 AT
VALENTINE AND AINSWORTH TO 43 AT IMPERIAL AND OGALLALA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CDT WED APR 8 2015
THE MAIN FORECAST CHALLENGE OVER THE NEXT TWO PERIODS IS
PRECIPITATION CHANCES AND PRECIPITATION TYPES OVERNIGHT TONIGHT.
FOR TODAY...EASTERLY WINDS WILL CONTINUE TO FAVOR LOW CLOUDS FOR
MOST OF THE FORECAST AREA. SOME CLEARING IS POSSIBLE IN THE
PANHANDLE ZONES AND ACROSS FAR SWRN PORTIONS OF THE CWA THIS
AFTERNOON...PER HRRR AND NAM12 H85 AND H85-H90 RH FIELDS. WITH
THIS IN MIND...FILTERED SUN WILL LEAD TO HIGHS IN THE UPPER 50S.
ELSEWHERE...HIGHS WILL RANGE FROM THE UPPER 40S TO LOWER 50S. LATE
THIS AFTERNOON AS THE UPPER LEVEL LOW PUSHES EAST INTO WESTERN
WYOMING...NRN UT AND NWRN COLORADO ELEVATED AND SURFACE BASED
INSTABILITY WILL BEGIN TO INCREASE ACROSS THE PANHANDLE. THE
LATEST NAM12 IS INDICATIVE OF NEGATIVE LI`S ACROSS THE PANHANDLE
FROM 21Z THROUGH 03Z AND ACROSS PORTIONS OF SWRN NEBRASKA WITH
ELEVATED INSTABILITY FROM 00Z THROUGH 06Z THIS EVENING. DID GO
AHEAD AND INTRODUCE THUNDERSTORMS TO THE FORECAST IN THE FAR WEST
AND SWRN CWA FOR LATE THIS AFTERNOON AND EVENING IN LIGHT OF THE
NEGATIVE LI/S. AS FOR PCPN CHANCES...THE HIGHEST POPS WILL
CONTINUE IN THE WEST AND NORTHWEST...TRANSITIONING ACROSS THE
SANDHILLS AND NORTH CENTRAL NEBRASKA OVERNIGHT. THESE AREAS ARE IN
THE MOST FAVORABLE AREAS FOR ISENTROPIC LIFT AHEAD OF THE APPG
TROUGH THIS EVENING...THEN IN THE WRAP AROUND OVERNIGHT. AS FOR
PRECIPITATION TYPE OVERNIGHT...DECIDED TO KEEP THE BULK OF PCPN AS
ALL RAIN AS BUFKIT SOUNDINGS INDICATE ONLY A 1 TO 2 HOUR WINDOW
FOR CHANGEOVER TO SNOW...AND THIS IS MAINLY THURSDAY MORNING
ACROSS THE FAR NORTHWESTERN AND NORTHERN CWA. DECIDED TO WORD THE
FCST AS RAIN OR SNOW...AS LOWS ARE ONLY EXPECTED TO DROP INTO 33
TO 35 DEGREE RANGE IN THE NORTHWEST OVERNIGHT. AS FOR SNOW
ACCUMS...DECIDED TO KEEP THESE AT A MINIMUM AS IT IS EXPECTED TO
MIX WITH RAIN...AND WARM GROUND CONDS SHOULD LIMIT ANY ACCUMS IF
THEY DO OCCUR.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 342 AM CDT WED APR 8 2015
UPPER LEVEL TROUGH AND ASSOCIATED COLD POOL WILL WORK EAST ACROSS
THE FORECAST AREA ON THURSDAY. PRECIPITATION IS EXPECTED TO
CONTINUE THROUGH MUCH OF THE MORNING HOURS...BUT BEGIN TO WANE IN
THE AFTERNOON AS SYSTEM RELATIVE UPGLIDE ASSOCIATED WITH A FRONTAL
BOUNDARY SHIFTS SOUTH AND EAST. IN ADDITION...LARGE SCALE LIFT
DECREASES AS THE TROUGH AXIS WORKS INTO EASTERN IOWA BY MID
AFTERNOON. PRECIPITATION AMOUNTS ARE ANTICIPATED TO BE LIGHT
DURING THE DAYLIGHT HOURS. MOST LOCATIONS WILL ONLY ACCUMULATE A
FEW ADDITIONAL TENTHS AT MOST. WHAT CONTINUES TO BE THE GREATEST
ENIGMA WITH THIS SYSTEM IS WHEN AND IF A CHANGE OVER TO SNOW WERE
TO OCCUR. ENOUGH MID AND UPPER LEVEL COOLING WILL HELP WITH THE
CHANGE OVER...ESPECIALLY SINCE H85-H9 TEMPERATURES FALL BELOW 0C
AFTER 12Z ACROSS OUR NORTHWEST THURSDAY MORNING. WOULD EXPECT THAT
THE FROZEN HYDROMETEOR WOULD MAKE IT TO THE SURFACE...BUT SFC T/S
ARE SHOWN LARGELY TO REMAIN JUST ABOVE 0C. CURRENT THINKING IS
THAT A CHANGE OVER WILL OCCUR...AFTER SUNRISE THURSDAY...BUT THEN
QUICKLY CHANGE BACK TO ALL RAIN AS THE DIURNAL HEATING TAKES
CONTROL. WHERE THERE IS ENHANCEMENT OF QPF FALLING AS SNOW...SOME
ACCUMULATION MAY OCCUR FOR AN HOUR OR TWO PERIOD. HOWEVER WITH THE
RECENT WARM SPELL GROUND TEMPERATURES WOULD SUPPORT MELTING...THUS
ACCUMULATIONS WOULD BE INSIGNIFICANT...A COUPLE TENTHS AT MOST.
NORTHWEST FLOW WILL TRANSPORT COOLER AIR INTO THE REGION
OVERNIGHT...WITH MORNING LOWS BELOW 0C FOR THE ENTIRE CWA FRIDAY
MORNING.
RETURN FLOW AND TRANSITORY UPPER RIDGING WILL PROMOTE A QUICK
WARM-UP ON FRIDAY. HIGHS WILL CLIMB BACK INTO THE 60S. THE RETURN
FLOW WILL ALLOW FOR AN INCREASE IN MOISTURE ACROSS THE HIGH PLAINS
AND WEST CENTRAL NEBRASKA. A THETA-E GRADIENT NOSES INTO THE
FORECAST AREA EARLY SATURDAY. ELEVATED INSTABILITY DEVELOPS ALONG
THE GRADIENT...WITH LI/S APPROACHING -5C BY SATURDAY AFTERNOON. A
FEW ELEVATED STORMS ARE POSSIBLE.
SUNDAY...A SIMILAR SETUP IS IN PLACE HOWEVER THE MODELS SHOW A COLD
FRONT ADVANCING ACROSS THE CWA EARLY AFTERNOON. MODEL CONSISTENCY
IS NOT TOO STRONG AT THIS POINT...BUT SUFFICIENT ENOUGH FOR A
MENTION OF THUNDERS ONCE AGAIN ESPECIALLY ALONG AND SOUTH OF THE
FRONT. WILL NEED TO WATCH AS PRE-FRONTAL CONDITIONS WOULD HAVE
SLIGHTLY MORE ENERGY TO WORK WITH.
THE PATTERN REMAINS ACTIVE EARLY NEXT WEEK...AND WILL HAVE TO WATCH
THE PROGRESSION OF A SOUTHERN STREAM CLOSED LOW...WHICH MAY BRING
ADDITIONAL CHANCES OF QPF TO THE REGION. THE INIT GAVE US SLIGHT
CHANCES...WHICH IS REASONABLE GIVEN A LACK OF CONSISTENCY IN THE
LONG RANGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1233 PM CDT WED APR 8 2015
WIDESPREAD LOW CLOUDS AND IFR/MVFR CONDITIONS WILL PERSIST THROUGH
TONIGHT ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. CEILINGS MAY
TEMPORARILY LIFT ACROSS PORTIONS OF SOUTHWEST NEBRASKA THIS
AFTERNOON...BUT LOWER ONCE AGAIN TONIGHT. AREAS OF FOG AND DRIZZLE
ARE ALSO POSSIBLE. AS A POTENT UPPER LEVEL DISTURBANCE AND
ASSOCIATED STRONG SURFACE LOW MOVE INTO THE AREA...SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS WILL DEVELOP THIS EVENING. THE
SHOWERS WILL TRANSITION TO MORE OF A STEADY RAIN AFTER MIDNIGHT
TONIGHT...POSSIBLY MIXING WITH WET SNOW ACROSS NORTHWEST AND
PORTIONS OF NORTH CENTRAL NEBRASKA. THE PRECIPITATION SHOULD BE
ENDING BY NOON TIME THURSDAY WITH OVERALL CONDITIONS IMPROVING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...JACOBS
AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
633 PM EDT WED APR 8 2015
.SYNOPSIS...
ROUNDS OF SHOWERS AND THUNDERSTORMS TONIGHT INTO THURSDAY NIGHT.
COLD FRONT CROSSES FRIDAY. HIGH PRESSURE FOR THE WEEKEND. COLD FRONT
APPROACHES AND THEN STALLS FOR UNSETTLED WEATHER EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
630 PM UPDATE...
UPDATED POPS TO REFLECT NEXT COMPLEX COMING INTO OUR SRN AND CENTRAL
ZONES AND THEN MOVING NEWD OVERNIGHT. ALSO WW33 IS GONE.
PREV DISCN...
BUSY DAY WITH LINE OF STRONG TO SEVERE STORMS CURRENTLY MOVING
THROUGH CWA. THIS IS ASSOCIATED WITH MCV PASSING JUST TO OUR NORTH
AND GOOD INFLOW INTO THE SOUTH. RELIED HEAVILY ON THE HRRR FOR
TIMING OF THE LINE...WHICH IS MOVING ESE AROUND 40KTS. THINGS
BECOME A BIT MORE UNCERTAIN TONIGHT...AS CONVECTION WILL BE
LINGERING AROUND A WEAK BOUNDARY THAT SHOULD BE NEAR OUR SOUTHERN
CWA BORDER. HRRR SHOWING TWO SEPARATE COMPLEXES MOVING ALONG THIS
BOUNDARY THIS EVENING INTO TONIGHT. GENERALLY HAVE GOTTEN AROUND A
HALF AN INCH IN TODAYS LINE OF CONVECTION...AND COULD GET ANOTHER
HALF TO ONE INCH OVERNIGHT. BELIEVE IT WOULD TAKE AROUND 1.5 INCHES
IN 3 HOURS TO START CREATING LOCAL PROBLEMS.
THIS BOUNDARY WILL SLOWLY LIFT NORTH AS A WARM FRONT THURSDAY
MORNING WITH SHOWERS AND T-STORMS. IN THE UNSTABLE WARM
SECTOR...COULD AGAIN SEE STRONG TO SEVERE STORMS APPROACH FROM THE
WEST THURSDAY AFTERNOON.
ONLY MINIMAL CHANGES MADE TO TEMPERATURE FORECAST THROUGH THE
PERIOD...AS EXISTING FORECAST LOOKED DECENT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
MODELS ARE IN GOOD AGREEMENT WITH THE STRONG COLD FRONT THAT MOVES
ACROSS LATE THURSDAY NIGHT AND FRIDAY MORNING. LOTS OF JUICE AND
GOOD DYNAMICS WILL BRING A BAND OF SHOWERS AND STRONG THUNDERSTORMS
ALONG AND AHEAD OF THE FRONT. SHOWERS AND STORMS END FROM WEST TO
EAST DURING FRIDAY...WITH THE FRONT EXITING THE MOUNTAINS BY LATER
IN THE AFTERNOON. HIGH PRESSURE BUILDS IN FROM THE WEST FOR A DRY
BUT COOLER START TO THE WEEKEND. ABOVE NORMAL TEMPERATURES FRIDAY
AHEAD OF THE FRONT WILL LOWER TO NEAR OR SLIGHTLY BELOW NORMAL
LEVELS BEHIND THE FRONT.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
NO SIGNIFICANT CHANGES WERE MADE TO THE EXTENDED PERIOD. WEEKEND
STARTS OUT WARM AND DRY...AND HIGH PRESSURE...SURFACE AND ALOFT
BUILDS IN. AN ACTIVE AND STORMY WEEK THEN TAKES HOLD NEXT WEEK...AS
ANOTHER FRONTAL BOUNDARY...STALLS OUT ACROSS THE AREA
BRIEFLY...BEFORE LIFTING BACK NORTH AS A WARM FRONT BY
TUESDAY...WITH LOW PRESSURE MOVING NORTHEAST OUT OF THE SOUTHERN
PLAINS TOWARDS THE OHIO VALLEY. THIS WILL PROVIDE THE SET UP FOR
WARM...AND HUMID WEATHER ACROSS THE AREA...ALONG WITH CHANCES FOR
THUNDERSTORMS IN THE INCREASINGLY MOIST AND UNSTABLE ATMOSPHERE. FOR
NOW...BROAD BRUSHED POPS IN THE EXTENDED...WITH A DIURNAL TREND TO
CONVECTION/HIGHER POPS.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
630 PM UPDATE...
UPDATED TAFS TO REFLECT CURRENT BREAK. MORE CONVECTION OVERSPREADS
THE AREA TONIGHT AS THE NEXT COMPLEX COMES UP THE OHIO VALLEY FROM
THE W.
PREV DISCN...
HAVE LINE OF THUNDERSTORMS MOVING ACROSS CWA...WITH IFR AND A
PERIOD OF WINDS GUSTING 30-40 KTS. HAVE IFR AT HTS/PKB/CRW...BUT
OPTED TO WAIT AT OTHER THREE SITES TO SEE HOW THINGS GO. STRONGEST
PART OF THE LINE LOOKS TO BE HEADED ACROSS MIDDLE AND SOUTHERN
CWA. OVERNIGHT...CANNOT RULE OUT A SHOWER OR THUNDERSHOWERS...BUT
COVERAGE SHOULD NOT BE VERY WIDESPREAD. AS A WEAK WARM FRONT LIFTS
NORTH ON THURSDAY...WILL HAVE A BETTER CHANCE OF SHOWERS AND
STORMS. CANNOT RULE OUT SOME FOG TONIGHT WHERE IT HAS
RAINED...ESPECIALLY IF FLOW DROPS OFF.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z FRIDAY...
FORECAST CONFIDENCE: LOW.
ALTERNATE SCENARIOS: TIMING/CATEGORY IN SHOWERS/STORMS MAY VARY.
UNCERTAIN ON FOG FORMATION TONIGHT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H M H H M H H H H H H H
BKW CONSISTENCY H H H M M H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 00Z FRIDAY...
BRIEF IFR POSSIBLE IN SHOWERS AND/OR THUNDERSTORMS THROUGH FRIDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR WVZ005-006-013.
OH...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR OHZ087.
KY...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR KYZ101>103-105.
VA...NONE.
&&
$$
SYNOPSIS...TRM/JMV/MZ/SL
NEAR TERM...TRM/MZ
SHORT TERM...JMV
LONG TERM...SL
AVIATION...TRM/MZ
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
343 PM EDT WED APR 8 2015
.SYNOPSIS...
A STATIONARY FRONT WILL REMAIN ACROSS THE AREA TONIGHT BUT SHOULD
LIFT NORTH ON THURSDAY AHEAD OF LOW PRESSURE APPROACHING THE GREAT
LAKES. THE LOW WILL MOVE ACROSS THE GREAT LAKES THURSDAY NIGHT AND
WILL DRAG A COLD FRONT THROUGH ON FRIDAY. HIGH PRESSURE WILL BUILD
IN FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
SHOWERS AND THUNDERSTORMS NOW IN THE EASTERN MOST COUNTIES OF THE
CWA WITH THE REMAINDER OF THE AREA DRY. NEAR TERM HIGH REZ
GUIDANCE HAS BEEN CHANGEABLE FOR THE EVENING AND FIRST HALF OF THE
NIGHT...FIRST DEVELOPING PRECIP IN THE AREA THIS EVENING AND NOW
NOT UNTIL MIDNIGHT OR SO NORTHWEST ON THE FRONT. WILL USE A BLEND
OF THE NAM AND HRRR AND HAVE PRECIP EAST MOVING OUT DURING THE
EVENING AND THEN MORE SHOWERS/THUNDER DEVELOPING TO OUR SOUTHWEST
AND WEST DRIFTING INTO THE AREA THROUGH THE EVENING. OVERNIGHT
CONTINUED TO INCREASE POPS TO CATEGORICAL FOR ALL BUT FAR
NORTHEAST. TEMPS TOUGH WITH THE FRONT AND LAKE INFLUENCES. NEAR
THE LAKE LOWS WILL BE IN THE LOWER 40S BUT INLAND A SHORT DISTANCE
50S LOOK BETTER.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
THURSDAY THE FRONT WILL HAVE TURNED WARM AND MOVED NORTH OF MUCH
OF THE AREA AHEAD OF LOW PRESSURE HEADING TOWARD THE CENTRAL LAKES.
GUIDANCE SUGGESTS IT GETS STUCK LIFTING OUT OF NERN
OHIO...POSSIBLY NEVER CLEARING OUT OF NWRN PA. WILL BE CLOSE.
OTHERWISE DEEP MOISTURE ACROSS THE AREA WITH MODERATE AMOUNTS OF
CAPE. GUIDANCE POPS HIGH AND WOULD BE TOUGH TO GO AGAINST THE
TREND. WILL HAVE CAT POPS FOR SHOWERS AND THUNDERSTORMS. WITH WARM
FRONT NORTH OF MOST HOWEVER TEMPS SHOULD TOUCH 70 MANY AREAS.
CONTINUED WET THURSDAY NIGHT AS COLD FRONT TRAILING THE LOW MOVES
THROUGH FROM WEST TO EAST. WILL CONTINUE WITH CAT POPS FOR SHOWERS
AND THUNDERSTORMS. FRIDAY THE DEEP MOISTURE MOVES EAST. GUIDANCE
SHOWS CLEARING MOVING IN FROM THE WEST ALTHOUGH MODELS ALSO SHOW
QUITE A BIT OF LOW LEVEL (850MB) MOISTURE REMAINING IN THE AREA.
NOT SURE I BUY THE RAPID CLEARING GUIDANCE IS FORECAST SO BACKED
OFF THE SPEED AT WHICH THIS MOVES IN. THAT SHOULD RESULT IN A
CLOUDY/MOSTLY CLOUDY START WITH COUNTIES BECOMING -PARTLY- SUNNY
FROM SOUTHWEST TO EAST. FRIDAY NIGHT WILL HOLD ONTO A SMALL CHANCE
POPS AS BOTH THE NAM AND GFS SHOW A SHORT WAVE MOVING THROUGH WITH
A GENERAL LONG WAVE TROUGH ACROSS THE LAKES. DRY SATURDAY AND
SATURDAY NIGHT BUT COOLER FOR THE WEEKEND WITH THE TROUGH ALOFT.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
MODELS IN GOOD AGREEMENT ON SUNDAY WITH HIGH PRESSURE SHIFTING EAST
OF THE FORECAST AREA AND MOVING OFF THE MID ATLANTIC COAST. SO
SUNDAY SHOULD BE WARMER AND DRY. TIMING OF THE NEXT SYSTEM STILL IN
DOUBT...GFS BRINGS WARM FRONT INTO AREA WITH CHANCE OF PRECIP MONDAY
NIGHT WHILE ECMWF A LITTLE SLOWER. FOR NOW WILL JUST GO LOW CHANCE
POPS MONDAY NIGHT. BOTH MODELS CONTINUE TO MOVE THE NEXT WAVE
THROUGH ON TUESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
FRONT LIFTED NORTH OF EVERYWHERE EXCEPT NW OH WHERE DENSE FOG WILL
LINGER THIS EVENING. ELSEWHERE SCATTERED TSRA WILL MOVE EAST OF
THE FORECAST BY EARLY EVENING. ANOTHER WAVE WILL DEVELOP TO THE
WEST AND MOVE INTO THE AREA OVERNIGHT...TIMING OF WHICH IS STILL
IN DOUBT.
.OUTLOOK...NON VFR SHOULD IMPROVE WEST TO EAST ON FRI WITH PASSAGE
OF COLD FRONT BUT AREAS OF NON VFR MAY HANG AROUND SNOWBELT INTO
EARLY SATURDAY.
&&
.MARINE...
HAVE DROPPED THE SMALL CRAFT ADVISORY AS NE WINDS HAVE DIMINISHED TO
5 TO 15 KNOTS. TOMORROW THE WINDS SHIFT TO THE SOUTH AND INCREASE TO
AROUND 20 KNOTS AHEAD OF NEXT SYSTEM. STRONG COLD FRONT WILL MOVE
ACROSS THE LAKE FRIDAY MORNING. 925MB WINDS INCREASE TO 50
KNOTS...NOT SURE HOW MUCH OF THAT CAN MIX DOWN AHEAD OF FRONT SO
WILL CONTINUE WITH 30 KNOTS IN THE FORECAST. COULD SEE A BRIEF
PERIOD OF 35 KNOT GALES WITH THE FRONT ITSELF. WINDS DIMINISH
QUICKLY BEHIND THE FRONT. HIGH PRESSURE BUILDS OVER THE LAKE
SATURDAY AND WILL REMAIN OVER THE LAKE THROUGH THE END OF THE
WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK
SHORT TERM...TK
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
327 PM EDT WED APR 8 2015
.SYNOPSIS...
ROUNDS OF SHOWERS AND THUNDERSTORMS TONIGHT INTO THURSDAY NIGHT.
COLD FRONT CROSSES AT THE END OF THE WORK WEEK. HIGH PRESSURE FOR
THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
BUSY DAY WITH LINE OF STRONG TO SEVERE STORMS CURRENTLY MOVING
THROUGH CWA. THIS IS ASSOCIATED WITH MCV PASSING JUST TO OUR NORTH
AND GOOD INFLOW INTO THE SOUTH. RELIED HEAVILY ON THE HRRR FOR
TIMING OF THE LINE...WHICH IS MOVING ESE AROUND 40KTS. THINGS
BECOME A BIT MORE UNCERTAIN TONIGHT...AS CONVECTION WILL BE
LINGERING AROUND A WEAK BOUNDARY THAT SHOULD BE NEAR OUR SOUTHERN
CWA BORDER. HRRR SHOWING TWO SEPARATE COMPLEXES MOVING ALONG THIS
BOUNDARY THIS EVENING INTO TONIGHT. GENERALLY HAVE GOTTEN AROUND A HALF
AN INCH IN TODAYS LINE OF CONVECTION...AND COULD GET ANOTHER HALF
TO ONE INCH OVERNIGHT. BELIEVE IT WOULD TAKE AROUND 1.5 INCHES IN
3 HOURS TO START CREATING LOCAL PROBLEMS.
THIS BOUNDARY WILL SLOWLY LIFT NORTH AS A WARM FRONT THURSDAY
MORNING WITH SHOWERS AND T-STORMS. IN THE UNSTABLE WARM
SECTOR...COULD AGAIN SEE STRONG TO SEVERE STORMS APPROACH FROM THE
WEST THURSDAY AFTERNOON.
ONLY MINIMAL CHANGES MADE TO TEMPERATURE FORECAST THROUGH THE
PERIOD...AS EXISTING FORECAST LOOKED DECENT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
MODELS ARE IN GOOD AGREEMENT WITH THE STRONG COLD FRONT THAT MOVES
ACROSS LATE THURSDAY NIGHT AND FRIDAY MORNING. LOTS OF JUICE AND
GOOD DYNAMICS WILL BRING A BAND OF SHOWERS AND STRONG THUNDERSTORMS
ALONG AND AHEAD OF THE FRONT. SHOWERS AND STORMS END FROM WEST TO
EAST DURING FRIDAY...WITH THE FRONT EXITING THE MOUNTAINS BY LATER
IN THE AFTERNOON. HIGH PRESSURE BUILDS IN FROM THE WEST FOR A DRY
BUT COOLER START TO THE WEEKEND. ABOVE NORMAL TEMPERATURES FRIDAY
AHEAD OF THE FRONT WILL LOWER TO NEAR OR SLIGHTLY BELOW NORMAL
LEVELS BEHIND THE FRONT.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
NO SIGNIFICANT CHANGES WERE MADE TO THE EXTENDED PERIOD. WEEKEND
STARTS OUT WARM AND DRY...AND HIGH PRESSURE...SURFACE AND ALOFT
BUILDS IN. AN ACTIVE AND STORMY WEEK THEN TAKES HOLD NEXT WEEK...AS
ANOTHER FRONTAL BOUNDARY...STALLS OUT ACROSS THE AREA
BRIEFLY...BEFORE LIFTING BACK NORTH AS A WARM FRONT BY
TUESDAY...WITH LOW PRESSURE MOVING NORTHEAST OUT OF THE SOUTHERN
PLAINS TOWARDS THE OHIO VALLEY. THIS WILL PROVIDE THE SET UP FOR
WARM...AND HUMID WEATHER ACROSS THE AREA...ALONG WITH CHANCES FOR
THUNDERSTORMS IN THE INCREASINGLY MOIST AND UNSTABLE ATMOSPHERE. FOR
NOW...BROAD BRUSHED POPS IN THE EXTENDED...WITH A DIURNAL TREND TO
CONVECTION/HIGHER POPS.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
HAVE LINE OF THUNDERSTORMS MOVING ACROSS CWA...WITH IFR AND A
PERIOD OF WINDS GUSTING 30-40 KTS. HAVE IFR AT HTS/PKB/CRW...BUT
OPTED TO WAIT AT OTHER THREE SITES TO SEE HOW THINGS GO. STRONGEST
PART OF THE LINE LOOKS TO BE HEADED ACROSS MIDDLE AND SOUTHERN
CWA. OVERNIGHT...CANNOT RULE OUT A SHOWER OR THUNDERSHOWERS...BUT
COVERAGE SHOULD NOT BE VERY WIDESPREAD. AS A WEAK WARM FRONT LIFTS
NORTH ON THURSDAY...WILL HAVE A BETTER CHANCE OF SHOWERS AND
STORMS. CANNOT RULE OUT SOME FOG TONIGHT WHERE IT HAS
RAINED...ESPECIALLY IF FLOW DROPS OFF.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z THURSDAY...
FORECAST CONFIDENCE: LOW.
ALTERNATE SCENARIOS: TIMING/CATEGORY IN SHOWERS/STORMS MAY VARY.
UNCERTAIN ON FOG FORMATION TONIGHT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H M H H M H H H H H H H
BKW CONSISTENCY H H H M M H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z THURSDAY...
BRIEF IFR POSSIBLE IN SHOWERS AND/OR THUNDERSTORMS THROUGH FRIDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH THURSDAY
MORNING FOR WVZ005-006-013.
OH...FLASH FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH THURSDAY
MORNING FOR OHZ087.
KY...FLASH FLOOD WATCH FROM 8 PM EDT THIS EVENING THROUGH THURSDAY
MORNING FOR KYZ101>103-105.
VA...NONE.
&&
$$
SYNOPSIS...JMV/MZ/SL
NEAR TERM...MZ
SHORT TERM...JMV
LONG TERM...SL
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
149 PM EDT WED APR 8 2015
.SYNOPSIS...
ROUNDS OF SHOWERS AND THUNDERSTORMS TONIGHT INTO THURSDAY NIGHT.
COLD FRONT CROSSES AT THE END OF THE WORK WEEK. HIGH PRESSURE FOR
THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
BUSY DAY WITH LINE OF STRONG TO SEVERE STORMS CURRENTLY MOVING
THROUGH CWA. THIS IS ASSOCIATED WITH MCV PASSING JUST TO OUR NORTH
AND GOOD INFLOW INTO THE SOUTH. RELIED HEAVILY ON THE HRRR FOR
TIMING OF THE LINE...WHICH IS MOVING ESE AROUND 40KTS. THINGS
BECOME A BIT MORE UNCERTAIN TONIGHT...AS CONVECTION WILL BE
LINGERING AROUND A WEAK BOUNDARY THAT SHOULD BE NEAR OUR SOUTHERN
CWA BORDER. THIS BOUNDARY WILL SLOWLY LIFT NORTH AS A WARM FRONT
THURSDAY MORNING WITH SHOWERS AND T-STORMS. DO NOT EXPECT THE
SHOWERS AND STORMS TONIGHT TO PRODUCING WIDESPREAD HEAVY
RAIN...BUT AS GROUND CONTINUES TO SOAK UP MORE WATER...FLOODING
CONCERNS WILL INCREASE. HOWEVER THINK ANY ISSUES THROUGH TONIGHT
AND TOMORROW WOULD BE VERY LOCALIZED...SO OPTED TO NOT ISSUE ANY
FLOOD HEADLINE AT THIS TIME. GENERALLY WILL GET AROUND HALF AN
INCH WITH THIS INITIAL LINE...THEN COULD GET ANOTHER QUARTER TO
HALF OVERNIGHT. BELIEVE IT WOULD TAKE AROUND 1.5 INCHES IN 3 HOURS
TO START CREATING LOCAL PROBLEMS.
ONLY MINIMAL CHANGES MADE TO TEMPERATURE FORECAST THROUGH THE
PERIOD...AS EXISTING FORECAST LOOKED DECENT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
MODELS ARE IN GOOD AGREEMENT WITH THE STRONG COLD FRONT THAT MOVES
ACROSS LATE THURSDAY NIGHT AND FRIDAY MORNING. LOTS OF JUICE AND
GOOD DYNAMICS WILL BRING A BAND OF SHOWERS AND STRONG THUNDERSTORMS
ALONG AND AHEAD OF THE FRONT. SHOWERS AND STORMS END FROM WEST TO
EAST DURING FRIDAY...WITH THE FRONT EXITING THE MOUNTAINS BY LATER
IN THE AFTERNOON. HIGH PRESSURE BUILDS IN FROM THE WEST FOR A DRY
BUT COOLER START TO THE WEEKEND. ABOVE NORMAL TEMPERATURES FRIDAY
AHEAD OF THE FRONT WILL LOWER TO NEAR OR SLIGHTLY BELOW NORMAL
LEVELS BEHIND THE FRONT.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
NO SIGNIFICANT CHANGES WERE MADE TO THE EXTENDED PERIOD. WEEKEND
STARTS OUT WARM AND DRY...AND HIGH PRESSURE...SURFACE AND ALOFT
BUILDS IN. AN ACTIVE AND STORMY WEEK THEN TAKES HOLD NEXT WEEK...AS
ANOTHER FRONTAL BOUNDARY...STALLS OUT ACROSS THE AREA
BRIEFLY...BEFORE LIFTING BACK NORTH AS A WARM FRONT BY
TUESDAY...WITH LOW PRESSURE MOVING NORTHEAST OUT OF THE SOUTHERN
PLAINS TOWARDS THE OHIO VALLEY. THIS WILL PROVIDE THE SET UP FOR
WARM...AND HUMID WEATHER ACROSS THE AREA...ALONG WITH CHANCES FOR
THUNDERSTORMS IN THE INCREASINGLY MOIST AND UNSTABLE ATMOSPHERE. FOR
NOW...BROAD BRUSHED POPS IN THE EXTENDED...WITH A DIURNAL TREND TO
CONVECTION/HIGHER POPS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
HAVE LINE OF THUNDERSTORMS MOVING ACROSS CWA...WITH IFR AND A
PERIOD OF WINDS GUSTING 30-40 KTS. HAVE IFR AT HTS/PKB/CRW...BUT
OPTED TO WAIT AT OTHER THREE SITES TO SEE HOW THINGS GO. STRONGEST
PART OF THE LINE LOOKS TO BE HEADED ACROSS MIDDLE AND SOUTHERN
CWA. OVERNIGHT...CANNOT RULE OUT A SHOWER OR THUNDERSHOWERS...BUT
COVERAGE SHOULD NOT BE VERY WIDESPREAD. AS A WEAK WARM FRONT LIFTS
NORTH ON THURSDAY...WILL HAVE A BETTER CHANCE OF SHOWERS AND
STORMS. CANNOT RULE OUT SOME FOG TONIGHT WHERE IT HAS
RAINED...ESPECIALLY IF FLOW DROPS OFF.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z THURSDAY...
FORECAST CONFIDENCE: LOW.
ALTERNATE SCENARIOS: TIMING/CATEGORY IN SHOWERS/STORMS MAY VARY.
UNCERTAIN ON FOG FORMATION TONIGHT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY M H H H H H H H H H H H
HTS CONSISTENCY M M M M H H M H H H H H
BKW CONSISTENCY H H H H H M M H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY M H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z THURSDAY...
BRIEF IFR POSSIBLE IN SHOWERS AND/OR THUNDERSTORMS THROUGH FRIDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/MZ/SL
NEAR TERM...MZ
SHORT TERM...JMV
LONG TERM...SL
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
144 PM EDT WED APR 8 2015
.SYNOPSIS...
A FRONTAL BOUNDARY NEAR THE AREA WILL KEEP CHANCES FOR SHOWERS IN
AND THUNDERSTORMS IN THE FORECAST THROUGH FRIDAY MORNING. AFTER A
COLD FRONT MOVES THROUGH FRIDAY MORNING HIGH PRESSURE WILL WORK
INTO THE REGION FOR THE START OF THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ORGANIZED SYSTEM OF CONVECTION HAS MAINTAINED ITSELF UPON ENTRY INTO
THE WESTERN PORTION OF THE CWA...AND SIGNS ARE THAT IT WILL
CONTINUE TO HOLD TOGETHER AND MAY EVEN INTENSIFY SOME AS IT
PROPAGATES EASTWARD ACROSS THE CWA FROM LATE MORNING THROUGH
EARLY/MID AFTERNOON. SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR
THE CWA MAINLY ALONG/SOUTH OF INTERSTATE 70. MAIN THREAT IS
DAMAGING WIND GUSTS...ALTHOUGH THERE MAY BE LOCALIZED LARGE HAIL.
SYNOPTICALLY...THERE IS A QUASI-STATIONARY BOUNDARY DRAPED ACROSS
CENTRAL/WESTERN OHIO. NEAR THIS BOUNDARY AND TO IT/S SOUTH IS
WHERE THE BEST MOISTURE/INSTABILITY WILL RESIDE AND WHERE THE
SEVERE WEATHER POTENTIAL EXISTS. THIS BOUNDARY LIKELY DOESN/T MOVE
MUCH DURING THE DAYTIME.
THE FATE OF THIS MCS WILL HELP DETERMINE WHAT OCCURS LATER THIS
AFTERNOON. CONVECTIVE EVOLUTION/DETAILS ARE QUITE UNCERTAIN IN
THE WAKE ON THIS MCS AND DIFFERENT MODELS SHOW DIFFERENT
SOLUTIONS. HAVE BEEN FOLLOWING NSSL WRF-ARW MOST CLOSELY UP TO
THIS POINT...ALTHOUGH LATEST RUN OF THE HRRR HAS NOW PICKED UP THE
MCS SHOWING A SIMILAR SOLUTION FOR WRF. THERE MAY BE A BREAK LULL
IN ACTIVITY AFTER THIS MCS MOVES THROUGH ALTHOUGH THE TAIL OF IT
MAY RE-ACTIVATE SOONER MAINLY ACROSS NORTHEAST KENTUCKY AND THEN
ADDITIONAL THUNDERSTORM DEVELOPMENT THEN MAY FOLLOW SUIT THROUGH
EVENING. POPS/WX HAVE BEEN RE-WORKED TO REFLECT THIS THINKING.
HAVE LOWERED MAX BY A DEG OR TWO GIVEN LOTS OF CLOUDS/CONVECTION
BUT STILL EXPECT CWA TO RISE AOA 70 FOR MAXIMA THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
EXPECT A LULL OR A DECREASE IN THE PRECIPITATION COVERAGE BRIEFLY
AT THE START OF THE SHORT TERM. ANOTHER DISTURBANCE WILL MOVE
THROUGH TONIGHT HOWEVER BRINGING A RETURN OF PRECIPITATION TO THE
REGION. YET ANOTHER WAVE BRINGS ADDITIONAL SHOWERS AND
THUNDERSTORMS TO THE FA ON THURSDAY. SOME OF THE THUNDERSTORMS ON
THURSDAY MAY BE SEVERE WITH DAMAGING WINDS AND LARGE HAIL THE
PRIMARY THREATS. A COLD FRONT APPROACHES THURSDAY EVENING AND
MOVES THROUGH THE REGION THURSDAY NIGHT INTO FRIDAY MORNING. AS
THIS STRONG COLD FRONT WORKS THROUGH THE REGION THERE IS THE
POTENTIAL FOR A DAMAGING WIND THREAT. HIGH PRESSURE WILL THEN WORK
INTO THE FA DURING THE DAY ON FRIDAY. COOLER AND DRIER AIR WILL
WORK INTO THE AREA FOR THE START OF THE WEEKEND.
NOT EXPECTING TEMPERATURES TO DROP MUCH WEDNESDAY NIGHT WITH LOW
TEMPERATURES IN THE MIDDLE 50S TO THE LOW 60S. DECENT SOUTHERLY
FLOW ON THURSDAY WILL ALLOW TEMPERATURES TO RISE INTO THE 70S TO
AROUND 80. WIND GUSTS WILL REACH UP AROUND 35 MPH AT TIMES ON
THURSDAY. ADDITIONAL WIND GUSTS ARE EXPECTED EARLY FRIDAY MORNING
AS THE FRONT MOVES THROUGH AND THE WINDS PICK UP.
CLOUD COVER IS EXPECTED TO DECREASE FRIDAY NIGHT. THIS WILL ALLOW
TEMPERATURES TO DROP OFF FRIDAY NIGHT. WITH THE DECREASE IN CLOUDS
AND THE COOLER AIR MASS WORKING INTO THE REGION ON FRIDAY TEMPERATURES
WILL DROP DOWN INTO THE 30S ACROSS A LARGE PORTION OF THE FA
FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
SURFACE HIGH PRESSURE AND A DRIER AIRMASS WILL BUILD INTO THE
AREA SATURDAY BEFORE SLIDING OFF TO THE EAST THROUGH THE DAY ON
SUNDAY. HIGHS ON SATURDAY WILL BE NEAR OR SLIGHTLY BELOW
NORMAL...RANGING FROM THE MID/UPPER 50S NORTH TO LOW 60S SOUTH. AS
WE START TO GET INTO SOME RETURN FLOW...HIGHS ON SUNDAY WILL PUSH
UP INTO THE 60S ACROSS THE ENTIRE FA. LOWS SATURDAY NIGHT WILL
BE DEPENDENT ON HOW FAST THE HIGH BUILDS IN AND THEN PUSHES OFF TO
THE EAST. WE MAY END UP WITH THE BEST RADIATIONAL COOLING ACROSS
OUR WEST SATURDAY MORNING AND THEN OUR EAST FOR SATURDAY
NIGHT/SUNDAY MORNING. WILL GENERALLY KEEP LOWS IN THE UPPER 30S TO
LOWER 40S...BUT SOME COLDER READINGS WILL BE POSSIBLE IF OPTIMAL
RADIATIONAL COOLING DEVELOPS.
IN DEVELOPING WAA...EXPECT SCATTERED SHOWERS AND PERHAPS A FEW
THUNDERSTORMS TO DEVELOP SUNDAY NIGHT. PCPN SHOULD THEN BECOME
MORE WIDESPREAD MONDAY INTO MONDAY NIGHT AS SHORTWAVE ENERGY PUSHES
EAST TOWARD THE REGION. EXPECT HIGHS ON MONDAY IN THE UPPER 60S TO
LOWERS 70S. AS THE SHORT WAVE PUSHES OFF TO THE EAST...PCPN SHOULD
TAPER OFF THROUGH THE DAY ON TUESDAY WITH HIGHS GENERALLY IN THE
60S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
BRUNT OF THE MCS HAD MOVED EAST OF THE TERMINALS AS OF 17Z. STILL
MAY HOLD ONTO MVFR CONDITIONS AT KCMH/KLCK FOR A COUPLE OF
HOURS...BUT TREND FOR A RETURN TO VFR IS LIKELY THROUGH THE REST
OF THE AFTERNOON. THERE IS LIKELY TO BE SOME RE-DEVELOPMENT OF
THUNDERSTORMS LATER IN THE AFTERNOON/EVENING. THERE IS UNCERTAINTY
REGARDING TIMING AND PLACEMENT...HOWEVER CONSENSUS IS FOR
KCVG/KLUK TO HAVE THE BEST CHANCE FOR CONVECTION AND HAVE INCLUDED
A TEMPO GROUP. JUST HAVE VCTS FOR THE REMAINING TERMINALS THIS
EVENING.
QUASI-STATIONARY BOUNDARY REMAINS IN PLACE TONIGHT/THURSDAY.
DISTURBANCES RIDING ALONG THE BOUNDARY WILL KEEP A CHANCE OF
SHOWERS/THUNDERSTORMS IN THE FORECAST. THERE MAY BE AN OVERNIGHT
LULL BUT THUNDERSTORMS MAY RETURN AS EARLY AS THURSDAY MORNING TO
THE TERMINALS.
OUTLOOK...THUNDERSTORMS POSSIBLE THURSDAY NIGHT/EARLY FRIDAY
MORNING AS A COLD FRONT MOVES THROUGH THE AREA. GUSTY WEST WINDS
ARE EXPECTED BEHIND THE COLD FRONT ON FRIDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...NOVAK
NEAR TERM...BPP
SHORT TERM...NOVAK
LONG TERM...JGL
AVIATION...BPP
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
117 PM EDT WED APR 8 2015
.SYNOPSIS...
A QUASI-STATIONARY FRONT WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PENNSYLVANIA TODAY THROUGH THURSDAY. A COLD FRONT
WILL MOVE THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...ADJUSTED TEMPS AGAIN BASED ON HRRR. POPS DECENT BUT
TRIMMED BACK THE FOG TO THE WEST.
ORIGINAL...THE SHOWER ACTIVITY FROM OVERNIGHT HAS DECREASED AS
EXPECTED. SHOWERS AND A FEW THUNDERSTORMS ARE FORMING TO THE WEST
AND THIS SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED TO INCREASE
LATE THIS MORNING AND INTO THE AFTERNOON. PATCHY DENSE FOG HAS
FORMED IN MANY LOCATIONS THIS MORNING...INCLUDING REPORTS IN NW
PA. I WILL EXPAND THE MENTION OF PATCHY DENSE FOG TO ALMOST ALL
AREAS FOR THE NEXT FEW HOURS. MINOR ADJUSTMENTS TO TEMPERATURES
AND PRECIPITATION TO REFLECT THE CURRENT TRENDS.
PREVIOUS DISCUSSION...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER NORTHERN OHIO AND
NORTHWEST PA TODAY. LITTLE MOVEMENT IS EXPECTED WITH THE FRONT
WHICH IS TYPICAL FOR THIS TIME OF YEAR AS THESE TYPE OF STATIONARY
FRONTS SET UP ON THE SOUTH SHORE OF LAKE ERIE. SHOWERS ARE EXPECTED
NEAR THE FRONTAL BOUNDARY TODAY BUT I DO NOT EXPECT WIDE SPREAD
AREAL COVERAGE. IT WILL BE TOUGH TO PREDICT THE TIMING. LOCALIZED
BOUNDARIES AND DAYTIME HEATING WILL MOST LIKELY TRIGGER THE SHOWERS.
THIS IS RE-ENFORCED BY THE HRRR MODEL AS SEVERAL RUNS INDICATED
SCATTERED/ISOLATED SHOWER PATTERN OVER THE REGION THROUGH THE DAY.
I WILL KEEP HIGH CHANCE TO LOW LIKELY RANGED POPS OVER THE AREA.
THUNDER IS POSSIBLE AND THE THREAT WILL INCREASE THIS AFTERNOON.
THE STORM PREDICTION CENTER HAS PLACED SOME OF THE NORTHWEST AND
NORTH CENTRAL OHIO IN A SLIGHT RISK CATEGORY FOR SEVERE
THUNDERSTORMS TODAY. BIG TEMPERATURE GRADIENT AGAIN NORTH TO SOUTH
ACROSS THE AREA. NORTHEAST FLOW NEAR THE LAKE WILL KEEP
TEMPERATURES MUCH COOLER
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
THE STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER THE FORECAST AREA
WEDNESDAY NIGHT INTO THURSDAY. WITH THE LACK OF STRONG DYNAMICS
EARLY IN THE PERIOD...THE SHOWERS WILL ONCE AGAIN BE DIFFICULT TO
TIME. SHOWERS AND A FEW THUNDERSTORMS WILL REMAIN OVER THE AREA BUT
IT WILL BE FAIRLY UNORGANIZED. AS THE SHORT WAVE IN ADVANCE OF THE
COLD FRONT BEGINS TO MOVE TOWARDS THE AREA THURSDAY...THE STATIONARY
FRONT WILL MOVE NORTHWARD AS A WARM FRONT AND THE UPPER LEVEL
SUPPORT WILL BECOME MORE FOCUSED. A LARGE AREA OF Q-VECTOR
CONVERGENCE IS NOTED THURSDAY NIGHT WITH THE UPPER LEVEL SYSTEM.
THE SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE MUCH MORE NUMEROUS
AND ORGANIZED ON THURSDAY NIGHT AND SEVERE WEATHER THREAT IS STILL A
QUESTION. THE TIMING IS NOT OPTIMAL AS THE BEST LIFT WILL OCCUR
DURING THE OVERNIGHT HOURS. WE WILL STILL CONTINUE TO MONITOR THE
THREAT. AT THIS TIME MOST OF THE FORECAST AREA HAS A MARGINAL RISK
FOR SEVERE THUNDERSTORMS THURSDAY NIGHT.
THE COLD FRONT WILL SWEEP ACROSS THE REGION ON FRIDAY. A FEW
SHOWERS AND A POSSIBLE THUNDERSTORM MAY LINGER OVER THE EASTERN
SECTIONS OF THE AREA FRIDAY MORNING BUT SHOWER ACTIVITY SHOULD
RAPIDLY DECREASE IN THE AFTERNOON. DRY AIR AND COLD ADVECTION WILL
OCCUR FRIDAY NIGHT. 850MB TEMPS AS LOW AS -8C COULD MOVE OVER THE
LAKE FRIDAY NIGHT INTO EARLY SATURDAY. A FEW WET SNOW FLAKES ARE
NOT OUT OF THE QUESTION FOR NE OH AND NW PA BUT I WILL LEAVE THE
MENTION OF SNOW OUT OF THE FORECAST AT THIS TIME. THE AIR IS VERY
DRY BEHIND THE FRONT AND IT MAY BE DIFFICULT TO GET ANY TYPE OF
PRECIPITATION WITHOUT ASSISTANCE FROM THE LAKE. HIGH PRESSURE WILL
BUILD OVER THE REGION LATE SATURDAY THROUGH SATURDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE OVER THE AREA SHOULD PROVIDE DRY CONDITIONS ON SUN
AND ALLOW TEMPS TO MODERATE BACK A FEW DEGREES ABOVE NORMAL. THE DRY
CONDITIONS WILL QUICKLY CHANGE GOING INTO SUN NIGHT AS RETURN FLOW
MOISTURE ARRIVES ALONG WITH A WEAK COLD FRONT FROM THE WEST. WILL
GENERALLY LEAVE SUN NIGHT FORECAST AS IS BUT ALLOW FOR A MORE
UNIFORM PRECIP THREAT ON MON. MODELS TRYING TO SHOW A REPEAT SETUP
OF THE CURRENT PATTERN WITH A FRONT STALLED NEAR THE AREA STARTING
BY TUE AND LASTING ALL WEEK SO WILL INCREASE POPS A LITTLE MORE.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
FRONT LIFTED NORTH OF EVERYWHERE EXCEPT NW OH WHERE DENSE FOG WILL
LINGER THIS EVENING. ELSEWHERE SCATTERED TSRA WILL MOVE EAST OF
THE FORECAST BY EARLY EVENING. ANOTHER WAVE WILL DEVELOP TO THE
WEST AND MOVE INTO THE AREA OVERNIGHT...TIMING OF WHICH IS STILL
IN DOUBT.
.OUTLOOK...NON VFR SHOULD IMPROVE WEST TO EAST ON FRI WITH PASSAGE
OF COLD FRONT BUT AREAS OF NON VFR MAY HANG AROUND SNOWBELT INTO
EARLY SATURDAY.
&&
.MARINE...
WILL LEAVE SCA FOR WEST PART OF THE LAKE GOING UNTIL 3 PM BUT COULD
BE TAKEN DOWN SOONER IF FRONT LIFTS INTO NEARSHORE WATERS A LITTLE
BEFORE THEN AND TURNS WINDS MORE SOUTH AT A DIMINISHED SPEED. MODELS
INDICATE THE FRONT MAY SAG BACK SOUTH OF THE LAKE TOWARD
EVENING...POSSIBLY DUE TO LAKE BREEZE ENHANCEMENT BUT THEN SHOULD
START TO LIFT BACK INTO THE LAKE LATER IN THE NIGHT AND CONTINUE OFF
TO THE NORTH ON THU. THE WARM AIR FLOWING OVER THE COLD LAKE SHOULD
PROVIDE A STABILIZING EFFECT SO WILL CONTINUE TO KEEP WINDS UNDER 20
KTS UNTIL THU NIGHT WHEN LOW LEVEL FLOW INCREASES MORE AND STARTS TO
TURN SW. THIS WILL PROVIDE MORE FAVORABLE CONDITIONS FOR WINDS TO
INCREASE TO AT LEAST 15 TO 25 KNOTS.
THE PASSAGE OF THE COLD FRONT LATE THU NIGHT AND FRI MORNING WILL
TURN THE WINDS TO THE WEST AND AS COLDER AIR MOVES IN CAN SEE WINDS
AROUND 30 KNOTS SO WILL INCREASE THE FORECAST. HIGH PRESSURE SLOWLY
PUSHES INTO OH TO GRADUALLY DIMINISH THE WINDS FRI NIGHT THRU SAT SO
THE SCA WILL END. NOT SURE IF THE ICE IS BROKEN UP ENOUGH OR NOT BUT
THIS MAY BE THE EVENT WHERE THE ICE TYPICALLY GETS PUSHED INTO THE
EAST END OF THE LAKE WITH THE STRONGER SW TO W WINDS.
THE HIGH WILL SHIFT OFF THE MID ATLANTIC COAST BY SUN NIGHT TO ALLOW
LIGHT WINDS TO TURN SE AND START TO INCREASE SOME.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
LEZ142>146.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET/TK
SHORT TERM...GARNET
LONG TERM...ADAMS
AVIATION...DJB
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS NORMAN OK
1213 PM CDT WED APR 8 2015
.AVIATION...
18Z TAFS...A COMPLEX OF HIGH BASED THUNDERSTORMS WILL MOVE ACROSS
SOUTHWESTERN AND SOUTHERN OKLAHOMA...AND WESTERN NORTH TEXAS...AND
MAY AFFECT KOUN/KOKC IN THE 18Z TO 20Z TIMEFRAME. THEREAFTER...A
SECOND ROUND OF MORE ISOLATED TSRA IS EXPECTED TO DEVELOP OVER
MAINLY NORTHERN AND WESTERN OKLAHOMA...AND TREK EASTWARD. WILL
INTRODUCE TEMPO GROUPS AND VCTS...AS CONFIDENCE REMAINS RELATIVELY
LOW ON TIMING AND IMPACTS TO ANY SINGLE TERMINAL. KPNC...ACROSS
NORTH CENTRAL OKLAHOMA...PROBABLY HAS THE BETTER CHANCE OF SEEING
TSRA IN THE 21Z THROUGH 00Z TIMEFRAME. SHRA/TSRA MAY LINGER BEYOND
00Z...WITH DECREASING INTENSITY. MVFR/IFR CIGS THEN LOOK TO
DEVELOP AHEAD OF AN APPROACHING FRONT...WHICH WILL RESULT IN A
NORTHWESTERLY WIND SHIFT FROM 09Z THROUGH 18Z THURS.
&&
.PREV DISCUSSION... /ISSUED 1126 AM CDT WED APR 8 2015/
DISCUSSION...
UPDATED POPS FOR LATE THIS MORNING/EARLY AFTERNOON TO ACCOUNT
FOR ELEVATED CONVECTION. SHOWERS AND A FEW STORMS SHOULD REACH
CENTRAL OKLAHOMA BETWEEN 1230-130 PM. STILL EXPECT SEVERE STORMS
WILL DEVELOP IN WESTERN AND NORTHERN OKLAHOMA...MAINLY AFTER 3-4
PM. A LITTLE UNSURE ABOUT RED FLAG WARNING IN FAR WESTERN OKLAHOMA
BUT DRY AIR SHOULD REACH AREAS WEST OF BUFFALO...WOODWARD AND ELK
CITY BY MID TO LATE AFTERNOON.
PREV DISCUSSION... /ISSUED 648 AM CDT WED APR 8 2015/
DISCUSSION...
THE 12Z AVIATION DISCUSSION FOLLOWS....
AVIATION...
A STATIONARY FRONT VERY NEAR THE OK/KS BORDER MAY SAG A LITTLE
FARTHER S THIS MORNING...BEFORE MOVING N AS A WARM FRONT LATER
TODAY. IF IT MOVES S OF KGAG/KWWR/KPNC EARLY THIS MORNING...LOW
CLOUDS AND BR/FG COULD MOVE INTO THOSE SITES...BUT SHOULD BE
SHORT-LIVED. TSRA MAY FORM THIS MORNING...MOST LIKELY ALONG
I-44...AND ARE EXPECTED TO BE ELEVATED IN NATURE...SO NOT LIKELY
SEVERE. MUCH MORE ROBUST TSRA...POSSIBLY WITH SEVERE
WEATHER...OUTFLOW...AND OTHER TYPICAL AVIATION HAZARDS...WILL
DEVELOP AROUND MID-AFTERNOON THROUGH THIS EVENING IF THE LOW-LEVEL
INVERSION CAN BE OVERCOME. THIS IS MOST LIKELY TO HAPPEN AT
KPNC...BUT IS ALSO POSSIBLE AT ALL OTHER TAF SITES. TSRA SHOULD
BECOME MORE NUMEROUS...BUT LESS SEVERE...OVERNIGHT AS THE DRYLINE
AND A COLD FRONT BEGIN TO ADVANCE E. LOW CEILINGS ARE LIKELY
TOMORROW MORNING IN ADVANCE OF THE DRYLINE/FRONT COMBINATION.
CMS
PREV DISCUSSION... /ISSUED 424 AM CDT WED APR 8 2015/
DISCUSSION...
AN APPROACHING UPPER-LEVEL WAVE MAY GENERATE A FEW
SHOWERS/THUNDERSTORMS THIS MORNING OR EARLY AFTERNOON OVER NORTH
TEXAS AND OKLAHOMA. THESE SHOWERS/STORMS WOULD BE ELEVATED...AND
WOULD POSE LITTLE OR NO RISK OF PRODUCING SEVERE WEATHER.
THE RISK OF SEVERE WEATHER LATER THIS AFTERNOON AND THIS EVENING
CONTINUES TO BE PROBLEMATIC...AS A RATHER STRONG CAPPING INVERSION
WILL REDUCE THE ABILITY OF STORMS TO DEVELOP IN AN OTHERWISE
FAVORABLE ENVIRONMENT FOR SEVERE WEATHER. WE CONTINUE WITH
RELATIVELY LOW PROBABILITIES OF RAIN...BUT IT IS STILL THE CASE
THAT ANY STORM OR STORMS THAT DO FORM WILL HAVE PLENTY OF
INSTABILITY AND SHEAR TO WORK WITH. THE PRESENCE OF A DRYLINE AND
STATIONARY FRONT WILL LIKELY OVERCOME THE CAP...AT LEAST NEAR THE
KANSAS BORDER...THIS AFTERNOON. THAT CONVECTION WILL LIKELY
GENERATE NEW CONVECTION AS OUTFLOW BOUNDARIES PROVIDE SUFFICIENT
LOW-LEVEL CONVERGENCE TO OVERCOME THE WEAKER PARTS OF THE CAP.
STORMS THAT DEVELOP WILL LIKELY PERSIST INTO THE NIGHT.
STORMS WILL CONTINUE OFF AND ON INTO TOMORROW AFTERNOON...AND AN
APPARENTLY SLOWER MOVEMENT OF THE COLD FRONT WILL KEEP RAIN
CHANCES IN OUR SOUTHEAST COUNTIES THROUGH EARLY FRIDAY. IN
ADDITION TO THE SLOWNESS...IT APPEARS THAT THE FRONT WILL NOT GO
VERY FAR SOUTH...AND RETURN MOISTURE WILL BRING RAIN CHANCES BACK
INTO OUR SOUTHERN COUNTIES FRIDAY EVENING...ELIMINATING THE ONLY
DAY THAT HAD BEEN FORECAST TO BE COMPLETELY RAIN-FREE BETWEEN NOW
AND THE EARLY PART OF NEXT WEEK.
SHOWERS AND STORMS WILL PROBABLY BECOME FAIRLY NUMEROUS OVER THE
WEEKEND...THEN DIMINISH SLOWLY IN PROBABILITY INTO EARLY NEXT
WEEK.
ALSO PROBLEMATIC TODAY IS THE WILDFIRE POTENTIAL FOR THIS
AFTERNOON AND THIS EVENING. ALL MODELS SHOW THE DRYLINE FARTHER
WEST THAN BEFORE...AND NONE OF THEM SUPPORT A RED FLAG WARNING
OUTSIDE THE NEW WARNING AREA...GENERALLY WEST OF A LINE FROM
WOODWARD TO SAYRE. THE HRRR DOES SHOW THE DRYLINE FARTHER EAST
THAN THIS...BUT DOES NOT HAVE SUFFICIENT WIND SPEEDS OUTSIDE THIS
AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 63 78 49 72 / 40 10 10 10
HOBART OK 61 78 46 73 / 20 10 10 10
WICHITA FALLS TX 66 84 51 74 / 30 10 10 10
GAGE OK 53 71 39 75 / 10 0 0 0
PONCA CITY OK 60 74 44 72 / 40 10 10 0
DURANT OK 66 77 53 73 / 30 30 40 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR OKZ004-009-010-
014-021.
TX...NONE.
&&
$$
06/84
AREA FORECAST DISCUSSION
NWS NORMAN OK
1126 AM CDT WED APR 8 2015
.DISCUSSION...
UPDATED POPS FOR LATE THIS MORNING/EARLY AFTERNOON TO ACCOUNT
FOR ELEVATED CONVECTION. SHOWERS AND A FEW STORMS SHOULD REACH
CENTRAL OKLAHOMA BETWEEN 1230-130 PM. STILL EXPECT SEVERE STORMS
WILL DEVELOP IN WESTERN AND NORTHERN OKLAHOMA...MAINLY AFTER 3-4
PM. A LITTLE UNSURE ABOUT RED FLAG WARNING IN FAR WESTERN OKLAHOMA
BUT DRY AIR SHOULD REACH AREAS WEST OF BUFFALO...WOODWARD AND ELK
CITY BY MID TO LATE AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 648 AM CDT WED APR 8 2015/
DISCUSSION...
THE 12Z AVIATION DISCUSSION FOLLOWS....
AVIATION...
A STATIONARY FRONT VERY NEAR THE OK/KS BORDER MAY SAG A LITTLE
FARTHER S THIS MORNING...BEFORE MOVING N AS A WARM FRONT LATER
TODAY. IF IT MOVES S OF KGAG/KWWR/KPNC EARLY THIS MORNING...LOW
CLOUDS AND BR/FG COULD MOVE INTO THOSE SITES...BUT SHOULD BE
SHORT-LIVED. TSRA MAY FORM THIS MORNING...MOST LIKELY ALONG
I-44...AND ARE EXPECTED TO BE ELEVATED IN NATURE...SO NOT LIKELY
SEVERE. MUCH MORE ROBUST TSRA...POSSIBLY WITH SEVERE
WEATHER...OUTFLOW...AND OTHER TYPICAL AVIATION HAZARDS...WILL
DEVELOP AROUND MID-AFTERNOON THROUGH THIS EVENING IF THE LOW-LEVEL
INVERSION CAN BE OVERCOME. THIS IS MOST LIKELY TO HAPPEN AT
KPNC...BUT IS ALSO POSSIBLE AT ALL OTHER TAF SITES. TSRA SHOULD
BECOME MORE NUMEROUS...BUT LESS SEVERE...OVERNIGHT AS THE DRYLINE
AND A COLD FRONT BEGIN TO ADVANCE E. LOW CEILINGS ARE LIKELY
TOMORROW MORNING IN ADVANCE OF THE DRYLINE/FRONT COMBINATION.
CMS
PREV DISCUSSION... /ISSUED 424 AM CDT WED APR 8 2015/
DISCUSSION...
AN APPROACHING UPPER-LEVEL WAVE MAY GENERATE A FEW
SHOWERS/THUNDERSTORMS THIS MORNING OR EARLY AFTERNOON OVER NORTH
TEXAS AND OKLAHOMA. THESE SHOWERS/STORMS WOULD BE ELEVATED...AND
WOULD POSE LITTLE OR NO RISK OF PRODUCING SEVERE WEATHER.
THE RISK OF SEVERE WEATHER LATER THIS AFTERNOON AND THIS EVENING
CONTINUES TO BE PROBLEMATIC...AS A RATHER STRONG CAPPING INVERSION
WILL REDUCE THE ABILITY OF STORMS TO DEVELOP IN AN OTHERWISE
FAVORABLE ENVIRONMENT FOR SEVERE WEATHER. WE CONTINUE WITH
RELATIVELY LOW PROBABILITIES OF RAIN...BUT IT IS STILL THE CASE
THAT ANY STORM OR STORMS THAT DO FORM WILL HAVE PLENTY OF
INSTABILITY AND SHEAR TO WORK WITH. THE PRESENCE OF A DRYLINE AND
STATIONARY FRONT WILL LIKELY OVERCOME THE CAP...AT LEAST NEAR THE
KANSAS BORDER...THIS AFTERNOON. THAT CONVECTION WILL LIKELY
GENERATE NEW CONVECTION AS OUTFLOW BOUNDARIES PROVIDE SUFFICIENT
LOW-LEVEL CONVERGENCE TO OVERCOME THE WEAKER PARTS OF THE CAP.
STORMS THAT DEVELOP WILL LIKELY PERSIST INTO THE NIGHT.
STORMS WILL CONTINUE OFF AND ON INTO TOMORROW AFTERNOON...AND AN
APPARENTLY SLOWER MOVEMENT OF THE COLD FRONT WILL KEEP RAIN
CHANCES IN OUR SOUTHEAST COUNTIES THROUGH EARLY FRIDAY. IN
ADDITION TO THE SLOWNESS...IT APPEARS THAT THE FRONT WILL NOT GO
VERY FAR SOUTH...AND RETURN MOISTURE WILL BRING RAIN CHANCES BACK
INTO OUR SOUTHERN COUNTIES FRIDAY EVENING...ELIMINATING THE ONLY
DAY THAT HAD BEEN FORECAST TO BE COMPLETELY RAIN-FREE BETWEEN NOW
AND THE EARLY PART OF NEXT WEEK.
SHOWERS AND STORMS WILL PROBABLY BECOME FAIRLY NUMEROUS OVER THE
WEEKEND...THEN DIMINISH SLOWLY IN PROBABILITY INTO EARLY NEXT
WEEK.
ALSO PROBLEMATIC TODAY IS THE WILDFIRE POTENTIAL FOR THIS
AFTERNOON AND THIS EVENING. ALL MODELS SHOW THE DRYLINE FARTHER
WEST THAN BEFORE...AND NONE OF THEM SUPPORT A RED FLAG WARNING
OUTSIDE THE NEW WARNING AREA...GENERALLY WEST OF A LINE FROM
WOODWARD TO SAYRE. THE HRRR DOES SHOW THE DRYLINE FARTHER EAST
THAN THIS...BUT DOES NOT HAVE SUFFICIENT WIND SPEEDS OUTSIDE THIS
AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 81 63 78 49 / 40 40 10 10
HOBART OK 85 61 78 46 / 30 20 10 10
WICHITA FALLS TX 81 66 84 51 / 30 30 10 10
GAGE OK 87 53 71 39 / 10 10 0 0
PONCA CITY OK 84 60 74 44 / 40 40 10 10
DURANT OK 79 66 77 53 / 20 30 30 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR OKZ004-009-010-
014-021.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PENDLETON OR
1025 AM PDT WED APR 8 2015
UPDATED AVIATION DISCUSSION
.UPDATE...TODAY AND TONIGHT...MOSTLY CLOUDY SKIES OVER MUCH OF THE
AREA THIS MORNING...EXCEPT A FEW BREAKS OVER THE YAKIMA VALLEY
EXTENDING DOWN INTO CENTRAL OREGON. CURRENT RADAR IS INDICATING A
FEW SPRINKLES OR LIGHT SHOWERS OVER THE NORTHERN BLUE MOUNTAINS AND
BLUE MOUNTAIN FOOTHILLS...ANYTHING THAT FALLS WILL BE VERY LIGHT
THROUGH 18Z. BY 19-21Z LATEST HRRR AND OTHER SHORT TERM GUIDANCE IS
INDICATING SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS DEVELOPING
OVER MUCH OF THE CWA IN RESPONSE TO INCREASED INSTABILITY ASSOCIATED
WITH THE UPPER LEVEL LOW CENTERED OVER NORTHERN NEVADA. THE BEST
CHANCE FOR SHOWERS AND THUNDERSTORMS WILL LIKELY BE FROM ABOUT 21Z
THIS AFTERNOON THROUGH 03Z THIS EVENING. AFTER 03Z THIS EVENING
SHOWERS AND ANY LINGERING STORMS WILL QUICKLY DECREASE IN COVERAGE
AS WE LOSE DAYTIME HEATING AND INSTABILITY. AFTER 06Z MOST AREAS
WILL DRY OUT WITH THE ONLY EXCEPTION BEING OVER THE NORTHERN BLUE
MOUNTAINS AND ESPECIALLY WALLOWA COUNTY WHERE THERE WILL BE A SLIGHT
CHC TO LOW END CHC FOR RAIN AND HIGHER ELEVATION SNOW SHOWERS
THROUGH THE OVERNIGHT. SNOW LEVELS WILL BE BETWEEN 4500 TO 5200 FEET
THIS AFTERNOON LOWERING SLIGHTLY TO BETWEEN 4200 TO 4700 FEET
OVERNIGHT. TEMPERATURES LOOKED FINE FOR TODAY AND TONIGHT WITH THE
LOWER ELEVATIONS AND BASINS RANGING FROM THE UPPER 50S TO MID 60S
THIS AFTERNOON AND THE MOUNTAINS IN THE 40S TO AROUND 50. OVERNIGHT
LOWS WILL REMAIN ABOVE FREEZING TONIGHT IN THE LOWER
ELEVATIONS...MAINLY IN THE MID TO UPPER 30S. THE MOUNTAINS AND
HIGHER PLATEAUS...INCLUDING CENTRAL OREGON...WILL FALL INTO THE 20S
OVERNIGHT. WINDS WILL INCREASE AN BECOME BREEZY OUT OF THE NORTHWEST
AT 8 TO 16 MPH FOR MOST LOCATIONS THIS AFTERNOON...ONE OF THE
WINDIER SPOTS WILL BE THE GRANDE RONDE VALLEY WHERE WINDS OF AROUND
20 MPH WITH GUSTS TO 30-35 MPH ARE EXPECTED THIS AFTERNOON. 77
.AVIATION...18Z TAFS...VFR CONDITIONS ARE EXPECTED FOR THE NEXT 24
HOURS. A LOW OFF THE COAST WILL KEEP A BKN DECK OF CLOUDS GENERALLY
BETWEEN 6000-8000 FEET OVER THE AREA THROUGH THIS AFTERNOON BUT
LOCALLY LOWER AROUND KRDM AND KBDN. AFTERNOON CONVECTIVE SHOWERS AND
PERHAPS A FEW ISOLATED THUNDERSTORMS ARE EXPECTED AFTER 21Z. NOT
ENOUGH CONFIDENCE TO MENTION VCTS OR -TSRA IN THE TAFS. WINDS WILL
GENERALLY REMAIN BELOW 15 KTS FOR THE NEXT 24 HOURS THOUGH KRDM,
KBDN AND KDLS WILL HAVE GUSTS TO 20 KTS AFTER 21Z...SHOWERS EXPECTED
TO DIMINISH AFTER 03-05Z THIS EVENING AT ALL TAF SITES.
&&
.PREV DISC... /ISSUED 415 AM PDT WED APR 8 2015/
SHORT TERM...TODAY THROUGH THURSDAY NIGHT...AN UPPER TROUGH WILL
REMAIN OVER THE REGION TODAY. A LOW CENTER AT THE BASE OF THE TROUGH
WILL WEAKEN AND SLIDE EAST TO WYOMING TODAY. THIS LOW HAS BEEN
SPREADING MOISTURE NORTH INTO CENTRAL AND NORTHEAST OREGON EARLY
THIS MORNING. PRECIP ASSOCIATED WITH THIS WRAP AROUND MOISTURE HAS
BEEN LIMITED THIS MORNING, MAINLY OVER CENTRAL OREGON. UPSLOPE
AFFECTS HAVE BEEN CAUSING LOCALLY ENHANCED RAIN AND/OR SNOW SOUTH
AND WEST OF BEND. THIS PRECIP SHOULD WIND DOWN TOWARDS DAYBREAK.
BEFORE THEN, LOCAL SNOW AMOUNTS OF AN INCH OR TWO COULD ACCUMULATE
OVER THESE UPSLOPE AREAS. LATE THIS MORNING THROUGH THIS EVENING,
COLD AIR ALOFT COMBINED WITH DAYTIME HEATING SHOULD PRODUCE ENOUGH
INSTABILITY FOR ISOLATED TO SCATTERED SHOWER OVER THE AREA. ALSO
STRAY THUNDERSTORMS WILL BE POSSIBLE LATE AFTERNOON AND EARLY
EVENING OVER MUCH OF THE ARE, THOUGH WESTERLY LOW LEVEL FLOW IS
CURRENTLY EXPECTED TO INHIBIT STORM DEVELOPMENT FROM THE GORGE SOUTH
TO CENTRAL OREGON. THE SHOWERS WILL DECREASE ACROSS THE AREA LATE
THIS EVENING AND OVERNIGHT, WITH ONLY A FEW SHOWERS LINGERING OVER
THE BLUES AND WALLOWA COUNTY. A WEAK PIECE OF ENERGY LOOKS TO DRIFT
OVER THE REGION THURSDAY. THIS ENERGY IS EXPECTED TO CAUSE A FEW
SHOWERS TO OCCUR OVER PORTIONS OF THE AREA, WITH THE POSSIBILITY OF
A STRAY THUNDERSTORM OVER OUR NORTHEASTERN ZONES. THESE SHOWERS AND
STORMS WILL DECREASE THROUGH THURSDAY EVENING, AND LARGELY END AFTER
MIDNIGHT. 90
LONG TERM...FRIDAY THROUGH TUESDAY...FRIDAY AN UPPER LEVEL TROUGH
WILL MOVE TOWARD WASHINGTON AND OREGON BRINGING WIND, RAIN AND
MOUNTAIN SNOW FRIDAY NIGHT AND SATURDAY. BREEZY TO WINDY CONDITIONS
WILL DEVELOP SATURDAY AS SURFACE PRESSURE GRADIENTS TIGHTEN BEHIND A
COLD FRONT AND STRONGER WINDS ALOFT MIX TO THE SURFACE. SOME WIND
ADVISORIES ARE POSSIBLE...PARTICULARLY IN THE LOWER COLUMBIA BASIN.
STRONG COLD ADVECTION BEHIND THE FRONT WILL DROP SNOW LEVELS TO
2000-3000 FT BY SUNDAY MORNING. SATURDAY NIGHT AND SUNDAY WESTERLY
FLOW WITH SOME EMBEDDED DISTURBANCES WILL BE OVER EASTERN WASHINGTON
AND OREGON. THESE DISTURBANCES WILL KEEP SOME UPSLOPE SHOWERS OVER
MOST OF THE AREA. AND TUESDAY MODELS DIVERGE SIGNIFICANTLY. ECMWF
HAS A WEAK TROUGH DEVELOPING OVER WASHINGTON AND OREGON. GFS HAS A
CLOSED LOW OVER THE EASTERN PACIFIC MONDAY THAT MOVES INLAND
TUESDAY. GFS ENSEMBLES SHOW ENOUGH SPREAD TO COVER BOTH
POSIBILITIES. THIS LOWERS CONFIDENCE IN ANY FORECAST TIMING AND
STRENGTH MONDAY AND TUESDAY. GIVEN THE MODELS DIFFERENCES MADE FEW
CHANGES TO CURRENT FORECAST OF A SLIGHT CHANCE OF RAIN SHOWERS IN
THE LOWER ELEVATIONS AND A CHANCE OF RAIN AND SNOW IN THE MOUNTAINS
SUNDAY NIGHT THROUGH TUESDAY. COONFIELD
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 60 37 63 38 / 30 30 10 20
ALW 62 42 64 42 / 30 30 20 20
PSC 65 38 67 37 / 20 30 10 10
YKM 62 37 64 35 / 30 20 10 10
HRI 64 37 67 34 / 30 30 10 10
ELN 62 36 65 33 / 30 20 10 10
RDM 54 24 61 28 / 40 20 10 10
LGD 55 33 57 34 / 40 40 20 30
GCD 56 32 62 33 / 50 40 20 20
DLS 63 40 68 40 / 20 20 10 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
77/91/91
AREA FORECAST DISCUSSION
NWS PENDLETON OR
917 AM PDT WED APR 8 2015
.UPDATE...TODAY AND TONIGHT...MOSTLY CLOUDY SKIES OVER MUCH OF THE
AREA THIS MORNING...EXCEPT A FEW BREAKS OVER THE YAKIMA VALLEY
EXTENDING DOWN INTO CENTRAL OREGON. CURRENT RADAR IS INDICATING A
FEW SPRINKLES OR LIGHT SHOWERS OVER THE NORTHERN BLUE MOUNTAINS AND
BLUE MOUNTAIN FOOTHILLS...ANYTHING THAT FALLS WILL BE VERY LIGHT
THROUGH 18Z. BY 19-21Z LATEST HRRR AND OTHER SHORT TERM GUIDANCE IS
INDICATING SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS DEVELOPING
OVER MUCH OF THE CWA IN RESPONSE TO INCREASED INSTABILITY ASSOCIATED
WITH THE UPPER LEVEL LOW CENTERED OVER NORTHERN NEVADA. THE BEST
CHANCE FOR SHOWERS AND THUNDERSTORMS WILL LIKELY BE FROM ABOUT 21Z
THIS AFTERNOON THROUGH 03Z THIS EVENING. AFTER 03Z THIS EVENING
SHOWERS AND ANY LINGERING STORMS WILL QUICKLY DECREASE IN COVERAGE
AS WE LOSE DAYTIME HEATING AND INSTABILITY. AFTER 06Z MOST AREAS
WILL DRY OUT WITH THE ONLY EXCEPTION BEING OVER THE NORTHERN BLUE
MOUNTAINS AND ESPECIALLY WALLOWA COUNTY WHERE THERE WILL BE A SLIGHT
CHC TO LOW END CHC FOR RAIN AND HIGHER ELEVATION SNOW SHOWERS
THROUGH THE OVERNIGHT. SNOW LEVELS WILL BE BETWEEN 4500 TO 5200 FEET
THIS AFTERNOON LOWERING SLIGHTLY TO BETWEEN 4200 TO 4700 FEET
OVERNIGHT. TEMPERATURES LOOKED FINE FOR TODAY AND TONIGHT WITH THE
LOWER ELEVATIONS AND BASINS RANGING FROM THE UPPER 50S TO MID 60S
THIS AFTERNOON AND THE MOUNTAINS IN THE 40S TO AROUND 50. OVERNIGHT
LOWS WILL REMAIN ABOVE FREEZING TONIGHT IN THE LOWER
ELEVATIONS...MAINLY IN THE MID TO UPPER 30S. THE MOUNTAINS AND
HIGHER PLATEAUS...INCLUDING CENTRAL OREGON...WILL FALL INTO THE 20S
OVERNIGHT. WINDS WILL INCREASE AN BECOME BREEZY OUT OF THE NORTHWEST
AT 8 TO 16 MPH FOR MOST LOCATIONS THIS AFTERNOON...ONE OF THE
WINDIER SPOTS WILL BE THE GRANDE RONDE VALLEY WHERE WINDS OF AROUND
20 MPH WITH GUSTS TO 30-35 MPH ARE EXPECTED THIS AFTERNOON. 77
&&
.PREV DISC... /ISSUED 415 AM PDT WED APR 8 2015/
SHORT TERM...TODAY THROUGH THURSDAY NIGHT...AN UPPER TROUGH WILL
REMAIN OVER THE REGION TODAY. A LOW CENTER AT THE BASE OF THE TROUGH
WILL WEAKEN AND SLIDE EAST TO WYOMING TODAY. THIS LOW HAS BEEN
SPREADING MOISTURE NORTH INTO CENTRAL AND NORTHEAST OREGON EARLY
THIS MORNING. PRECIP ASSOCIATED WITH THIS WRAP AROUND MOISTURE HAS
BEEN LIMITED THIS MORNING, MAINLY OVER CENTRAL OREGON. UPSLOPE
AFFECTS HAVE BEEN CAUSING LOCALLY ENHANCED RAIN AND/OR SNOW SOUTH
AND WEST OF BEND. THIS PRECIP SHOULD WIND DOWN TOWARDS DAYBREAK.
BEFORE THEN, LOCAL SNOW AMOUNTS OF AN INCH OR TWO COULD ACCUMULATE
OVER THESE UPSLOPE AREAS. LATE THIS MORNING THROUGH THIS EVENING,
COLD AIR ALOFT COMBINED WITH DAYTIME HEATING SHOULD PRODUCE ENOUGH
INSTABILITY FOR ISOLATED TO SCATTERED SHOWER OVER THE AREA. ALSO
STRAY THUNDERSTORMS WILL BE POSSIBLE LATE AFTERNOON AND EARLY
EVENING OVER MUCH OF THE ARE, THOUGH WESTERLY LOW LEVEL FLOW IS
CURRENTLY EXPECTED TO INHIBIT STORM DEVELOPMENT FROM THE GORGE SOUTH
TO CENTRAL OREGON. THE SHOWERS WILL DECREASE ACROSS THE AREA LATE
THIS EVENING AND OVERNIGHT, WITH ONLY A FEW SHOWERS LINGERING OVER
THE BLUES AND WALLOWA COUNTY. A WEAK PIECE OF ENERGY LOOKS TO DRIFT
OVER THE REGION THURSDAY. THIS ENERGY IS EXPECTED TO CAUSE A FEW
SHOWERS TO OCCUR OVER PORTIONS OF THE AREA, WITH THE POSSIBILITY OF
A STRAY THUNDERSTORM OVER OUR NORTHEASTERN ZONES. THESE SHOWERS AND
STORMS WILL DECREASE THROUGH THURSDAY EVENING, AND LARGELY END AFTER
MIDNIGHT. 90
LONG TERM...FRIDAY THROUGH TUESDAY...FRIDAY AN UPPER LEVEL TROUGH
WILL MOVE TOWARD WASHINGTON AND OREGON BRINGING WIND, RAIN AND
MOUNTAIN SNOW FRIDAY NIGHT AND SATURDAY. BREEZY TO WINDY CONDITIONS
WILL DEVELOP SATURDAY AS SURFACE PRESSURE GRADIENTS TIGHTEN BEHIND A
COLD FRONT AND STRONGER WINDS ALOFT MIX TO THE SURFACE. SOME WIND
ADVISORIES ARE POSSIBLE...PARTICULARLY IN THE LOWER COLUMBIA BASIN.
STRONG COLD ADVECTION BEHIND THE FRONT WILL DROP SNOW LEVELS TO
2000-3000 FT BY SUNDAY MORNING. SATURDAY NIGHT AND SUNDAY WESTERLY
FLOW WITH SOME EMBEDDED DISTURBANCES WILL BE OVER EASTERN WASHINGTON
AND OREGON. THESE DISTURBANCES WILL KEEP SOME UPSLOPE SHOWERS OVER
MOST OF THE AREA. AND TUESDAY MODELS DIVERGE SIGNIFICANTLY. ECMWF
HAS A WEAK TROUGH DEVELOPING OVER WASHINGTON AND OREGON. GFS HAS A
CLOSED LOW OVER THE EASTERN PACIFIC MONDAY THAT MOVES INLAND
TUESDAY. GFS ENSEMBLES SHOW ENOUGH SPREAD TO COVER BOTH
POSIBILITIES. THIS LOWERS CONFIDENCE IN ANY FORECAST TIMING AND
STRENGTH MONDAY AND TUESDAY. GIVEN THE MODELS DIFFERENCES MADE FEW
CHANGES TO CURRENT FORECAST OF A SLIGHT CHANCE OF RAIN SHOWERS IN
THE LOWER ELEVATIONS AND A CHANCE OF RAIN AND SNOW IN THE MOUNTAINS
SUNDAY NIGHT THROUGH TUESDAY. COONFIELD
AVIATION...12Z TAFS...VFR CONDITIONS ARE EXPECTED FOR THE NEXT 24
HOURS. A LOW OFF THE COAST WILL KEEP SOME MID AND HIGH LEVEL CLOUDS
GENERALLY ABOVE 5000 FEET OVER THE AREA THROUGH THIS AFTERNOON.
AFTERNOON CONVECTIVE SHOWERS AND PERHAPS A FEW ISOLATED
THUNDERSTORMS ARE EXPECTED AFTER 20Z. NOT ENOUGH CONFIDENCE TO
MENTION VCTS OR -TSRA IN THE TAFS. WINDS WILL GENERALLY REMAIN BELOW
15 KTS FOR THE NEXT 24 HOURS THOUGH KRDM, KBDN AND KDLS WILL HAVE
GUSTS TO 20 KTS AFTER 21Z...SHOWERS EXPECTED TO DIMINISH AFTER 03Z
THIS EVENING AT ALL TAF SITES.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 60 37 63 38 / 30 30 10 20
ALW 62 42 64 42 / 30 30 20 20
PSC 65 38 67 37 / 20 30 10 10
YKM 62 37 64 35 / 30 20 10 10
HRI 64 37 67 34 / 30 30 10 10
ELN 62 36 65 33 / 30 20 10 10
RDM 54 24 61 28 / 40 20 10 10
LGD 55 33 57 34 / 40 40 20 30
GCD 56 32 62 33 / 50 40 20 20
DLS 63 40 68 40 / 20 20 10 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
77/91/91
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
601 PM EDT WED APR 8 2015
.SYNOPSIS...
A NEARLY STATIONARY FRONT JUST SOUTH OF PENNSYLVANIA
AND STRONG HIGH PRESSURE OVER QUEBEC WILL COMBINE TO KEEP MOIST
AND COOL CONDITIONS OVER THE REGION THROUGH THURSDAY. A STORM
SYSTEM WILL BRING A COLD FRONT ACROSS PENNSYLVANIA DURING FRIDAY.
AFTER A WARM DAY ON FRIDAY...MUCH COOLER CONDITIONS WILL FOLLOW
FOR SATURDAY. TEMPERATURES WILL MODERATE BACK TO MILDER CONDITIONS
NEXT WEEK. THERE COULD BE A SHOWER FROM TIME TO TIME NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
CENTRAL PA REMAINS FIRMLY ENTRENCHED IN A COOL AIR DAMMING REGIME
BETWEEN STRONG-COLD HIGH PRESSURE OVER THE APPALACHIANS. MAIN
FEATURE OF NOTE THIS EVENING IS WELL DEFINED SHORTWAVE/MCV
TRACKING ACROSS SOUTHERN PA. REGIONAL RADAR LOOP AT 21Z SHOWS
WEAKENING CONVECTION MOVING INTO THE ALLEGHENY MTNS AS IT
ENCOUNTERS COOL/STABLE AIR MASS. HOWEVER...LG SCALE FORCING AHEAD
OF THIS FEATURE WILL LIKELY SUPPORT A PERIOD OF SHOWERS ACROSS
MOST OF CENTRAL PA AS IT MOVES THRU THIS EVENING. RADAR TRENDS AND
LATEST HRRR OUTPUT SUGGEST THE SHOWERS WILL BE EXITING THE EASTERN
COUNTIES BY ARND 03Z.
IN THE WAKE OF THIS EVENING/S SHORTWAVE...EXPECT DRY CONDS FOR
MOST OF THE REGION LATE TONIGHT. THE EXCEPTION WILL BE ACROSS THE
SOUTHWEST COUNTIES...WHERE SHOWERS MAY ARRIVE TOWARD DAWN IN ASSOC
WITH INCREASING ISENTROPIC LIFT IN ADVANCE OF DEVELOPING STORM
SYSTEM/SOUTHERLY LL JET OVR THE MIDWEST.
BLEND OF LATEST GUIDANCE KEEPS TEMPS NEARLY STEADY OVERNIGHT WITH LOWS
RANGING FROM THE U30S OVR THE HIGH TERRAIN NORTH AND EAST OF
KIPT...TO THE M40S ALONG THE SPINE OF THE ALLEGHENY MTNS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
ANOTHER COOL/CLOUDY DAY ON TAP FOR THURSDAY...AS CENTRAL PA
REMAINS IN CAD REGIME. THERE WILL BE AN INCREASING CHC OF
SHOWERS...ESP OVR THE NW MTNS BY AFTN...AS SWRLY LL JET ASSOC
WITH DEVELOPING LOW OVR THE MIDWEST APPROACHES. GEFS 8H MFLUX
VALUES SKYROCKET TO 5SD ABV NORMAL ACROSS NW PA BY 00Z THU. BASED
ON LATEST ENSEMBLE OUTPUT...WILL MAINTAIN CATEGORICAL POPS ACROSS
THE NW MTNS...TO CHC ACROSS THE LOWER SUSQ VALLEY.
LIFTED INDEX PROGS INDICATE ALL OF CENTRAL PA WILL REMAIN STRONGLY
DAMMED. HOWEVER...ELEVATED TSRA A DEFINITE POSSIBILITY ACROSS THE
NW COUNTIES LATE IN THE DAY.
HIGHS WILL BE WITHIN A DEGREE OR TWO OF TODAY IN MOST AREAS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
NOT A LOT OF CHANGE TO PACKAGE FROM RECENT DAYS.
MAIN CHANGE WAS TO UP TEMPERATURES THU NIGHT...GIVEN THAT 850 MB
FRONT IS WELL NORTH OF THE AREA...AND VERY STRONG LOW LEVEL FLOW
IS EXPECTED ACROSS THE AREA.
ALSO DID UP TEMPERATURES ON FRIDAY...GIVEN NEW GUIDANCE AND THAT
850 MB FRONT IS NORTH OF THE AREA. HAVE INCREASING CONCERN FOR
AT LEAST A FEW STRONG STORMS ACROSS THE AREA. EARLY ON...FAR WEST
MAY SEE ONE...GIVEN STRONGER WIND FIELDS TO THE WEST.
LATER ON...TEMPERATURES IN THE 70 TO 75 DEGREE RANGE...WITH DEWPTS
IN THE 50S...MAY LEAD SOME STORMS LATER IN THE AFT...EVEN WITH NOT
THE BEST HEIGHT FALLS.
ONE ONLY HAS TO LOOK OVER COLD LAKE ERIE. CONVECTION FORMED ALONG
THE LAKE SHORE...WITH JUST SOME MINOR AMTS OF HEATING THIS AFT.
ANYWAY...DID LOWER TEMPS FOR FRIDAY NIGHT INTO SAT. A RATHER
STRONG SMALL UPPER LEVEL TROUGH MOVES ACROSS THE AREA FOR LATE
FRIDAY INTO SAT.
MAIN THING WAS TO PUT BACK IN A CHC OF SHOWERS FOR LATE FRIDAY
NIGHT INTO SATURDAY ACROSS THE FAR NORTH...GIVEN STRONG DYNAMICS
WITH A STRONG UPPER LEVEL LOW. PAST EXPERIENCE WITH THIS SITUATION
USUALLY LEADS TO SOME SHOWERS.
OVERALL...THE WEEKEND LOOKS SIMILAR TO LAST WEEKEND. BREEZY AND
COOL ON SAT. WARMER ON SUNDAY.
DID UP POPS TO 30 PERCENT FROM LATE MONDAY INTO WED MORNING TO
FIT IN WITH OTHERS BETTER. STILL SOME SPREAD ON THE DETAILS. LOOKS
LIKE MODELS AND HPC HAVE COLD FRONT MOVING INTO THE AREA ON TUE.
FRONT MAY NOT CLEAR TO WED. DID UP TEMPERATURES SOME TOO.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
WIDESPREAD IFR/MVFR WILL CONTINUE NORTH OF THE FRONTAL SYSTEM THAT
IS STALLED SOUTH OF PA. THIS STATIONARY FRONTAL BOUNDARY WILL
KEEP LOW LEVEL MOISTURE LOCKED IN PLACE TONIGHT AND THURSDAY.
AREAS OF DRIZZLE WITH SCATTERED SHOWERS WILL BE THE RULE WITH
LITTLE IF ANY IMPROVEMENT EXPECTED.
WINDS WILL REMAIN FROM THE EAST OR SOUTHEAST AT 5-10 MPH THROUGH
THE PERIOD.
OUTLOOK...
FRI...A COLD FRONT WILL BRING MORE REDUCTIONS WITH RAIN SHOWERS
AND POSSIBLE THUNDERSTORMS...ESPECIALLY DURING THE AFTERNOON.
SAT-MON...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/MARTIN
NEAR TERM...FITZGERALD/LA CORTE
SHORT TERM...FITZGERALD/LA CORTE
LONG TERM...MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
336 PM EDT WED APR 8 2015
.SYNOPSIS...
A NEARLY STATIONARY FRONT JUST SOUTH OF PENNSYLVANIA
AND STRONG HIGH PRESSURE OVER QUEBEC WILL COMBINE TO KEEP MOIST
AND COOL CONDITIONS OVER THE REGION THROUGH THURSDAY. A STORM
SYSTEM WILL BRING A COLD FRONT ACROSS PENNSYLVANIA DURING FRIDAY.
AFTER A WARM DAY ON FRIDAY...MUCH COOLER CONDITIONS WILL FOLLOW
FOR SATURDAY. TEMPERATURES WILL MODERATE BACK TO MILDER CONDITIONS
NEXT WEEK. THERE COULD BE A SHOWER FROM TIME TO TIME NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
WE REMAIN FIRMLY ENTRENCHED IN A COOL AIR DAMMING REGIME BETWEEN
STRONG-COLD HIGH PRESSURE OVER SOUTHERN CANADA AND A STATIONARY
FRONT WHICH DOG LEGS FROM WRN PA SOUTH THROUGH WEST VIRGINIA ALL
THE WAY THROUGH SOUTHERN VA BEFORE TURNING EAST AND OFF THE COAST
NEAR THE DEL MARVA.
ALOFT WE ARE ACTUALLY UNDER A FLAT UPPER RIDGE WITH 500 HEIGHTS
THAT ARE SLIGHTLY ABOVE NORMAL FOR THE SEASON. HOWEVER THE FAST
WSW FLOW IS SERVING AS A PATHWAY TO FUNNEL WEAK SHORTWAVES AND
MOISTURE OUR WAY FROM THE LARGE SCALE UPPER TROF OVER THE ROCKY
MOUNTAIN STATES.
THE WARM-MOIST ADVECTION IS PROGGED TO CONTINUE AS THE SURFACE
HIGH TO OUR NORTH STUBBORNLY MAINTAINS A LOW LEVEL EAST OR
SOUTHEAST FLOW. WHILE THE AREA OF MORE ORGANIZED SHOWERS HAS MOVED
OUT OF MY EASTERN ZONES...WE CANNOT RULE OUT THE THREAT FOR MORE
RAIN THROUGH LATE DAY AS THE WEAK LIFT CONTINUES. I EVEN
INTRODUCED A SMALL CHANCE FOR A RUMBLE OF THUNDER. DESPITE HIGH
TEMPS THAT WILL ONLY AVERAGE IN THE 40S OVER MOST OF THE
AREA...MID LEVEL LAPSE RATES ARE SHOWN BY THE RAP TO EXCEED 6C/KM
AS THE MOIST WARM ADVECTION CONTINUES...SO SOME ELEVATED
CONVECTION CANNOT BE RULED OUT.
HIGH TEMPS THIS AFTERNOON WILL AVERAGE IN THE LOW TO MID 40S. FAR
SWRN ZONES MAY BREAK OUT INTO THE MID 50S FOR A SHORT TIME.
CLOUDY...COOL AND DAMP CONDITIONS WILL CONTINUE TONIGHT AS HIGH
PRESSURE OVER QUEBEC CANADA NOSES SWWD INTO THE STATE ACCOMPANIED
BY A LIGHT EAST TO NE BREEZE. THIS SHOULD LEAD TO WIDESPREAD LOW
CLOUDS AND RIDGE-SHROUDING FOG ACROSS MUCH OF THE REGION WITH THE
LOWEST VSBYS ON THE EAST FACING UPPER SLOPES.
MAIN QUESTION WILL CENTER ON HOW MUCH OF THE OHIO CONVECTION CAN
SURVIVE THE TREK INTO OUR WEDGE OF COLD AND STABLE AIR. LATEST
HRRR SHOWS A CLUSTER OF SHOWERS MOVING ACROSS FAR NRN PA THROUGH
EARLY EVENING WHILE THE MAIN MCS/BOW ECHO TRACKS OFF TO OUR SOUTH
TOWARD THE DEEPEST INSTABILITY. FOR MOST OF PA THE HRRR SHOWS THE
CHANCE OF SCATTERED SHOWERS NOT SHOWING ANY PARTICULAR
ORGANIZATION. A BLEND OF MODEL POPS SHOWS PRETTY MUCH A 50-50 COIN
FLIP FOR RAIN IN MOST AREAS OVERNIGHT...BUT THAT SEEMS A PRETTY
ACCURATE REPRESENTATION FOR WHAT IS LIKELY TO OCCUR. ALONG WITH
AREAS OF FOG AND DRIZZLE IT POINTS TO MORE COOL-DAMP CONDITIONS
OVERNIGHT.
LATEST HIGH RES GUIDANCE KEEPS OVERNIGHT LOWS MAINLY IN THE
40S...MINIMIZING THE THREAT FOR POCKETS OF FREEZING DRIZZLE OVER
OUR FAR NERN ZONES THAT WE WERE CONCERNED WITH EARLIER.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
THURSDAY LOOKS LIKE A CARBON COPY OF TODAY AS THE HIGH ONLY SLOWLY
RETREATS TOWARD THE CANADIAN MARITIMES. LIFTED INDEX PROGS
INDICATE WE REMAIN STRONGLY DAMMED OVER MOST OF THE AREA
THROUGHOUT THE DAY WHILE WARM MOIST ADVECTION OVER THE LOW LEVEL
COLD WEDGE KEEPS US VULNERABLE TO SCATTERED SHOWERS AND POSSIBLY
AN ELEVATED THUNDERSTORM. HARD TO TIME IN ANY PARTICULAR FEATURE
AT THIS RANGE...AS THIS WILL LIKELY DEPEND ON ANY REMNANTS OF OHIO
VALLEY CONVECTION THAT CAN ORGANIZE IN THE HIGH CAPE AIR IN THE
WARM SECTOR.
HIGHS WILL BE WITHIN A DEGREE OR TOW OF TODAY IN MOST AREAS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
NOT A LOT OF CHANGE TO PACKAGE FROM RECENT DAYS.
MAIN CHANGE WAS TO UP TEMPERATURES THU NIGHT...GIVEN THAT 850 MB
FRONT IS WELL NORTH OF THE AREA...AND VERY STRONG LOW LEVEL FLOW
IS EXPECTED ACROSS THE AREA.
ALSO DID UP TEMPERATURES ON FRIDAY...GIVEN NEW GUIDANCE AND THAT
850 MB FRONT IS NORTH OF THE AREA. HAVE INCREASING CONCERN FOR
AT LEAST A FEW STRONG STORMS ACROSS THE AREA. EARLY ON...FAR WEST
MAY SEE ONE...GIVEN STRONGER WIND FIELDS TO THE WEST.
LATER ON...TEMPERATURES IN THE 70 TO 75 DEGREE RANGE...WITH DEWPTS
IN THE 50S...MAY LEAD SOME STORMS LATER IN THE AFT...EVEN WITH NOT
THE BEST HEIGHT FALLS.
ONE ONLY HAS TO LOOK OVER COLD LAKE ERIE. CONVECTION FORMED ALONG
THE LAKE SHORE...WITH JUST SOME MINOR AMTS OF HEATING THIS AFT.
ANYWAY...DID LOWER TEMPS FOR FRIDAY NIGHT INTO SAT. A RATHER
STRONG SMALL UPPER LEVEL TROUGH MOVES ACROSS THE AREA FOR LATE
FRIDAY INTO SAT.
MAIN THING WAS TO PUT BACK IN A CHC OF SHOWERS FOR LATE FRIDAY
NIGHT INTO SATURDAY ACROSS THE FAR NORTH...GIVEN STRONG DYNAMICS
WITH A STRONG UPPER LEVEL LOW. PAST EXPERIENCE WITH THIS SITUATION
USUALLY LEADS TO SOME SHOWERS.
OVERALL...THE WEEKEND LOOKS SIMILAR TO LAST WEEKEND. BREEZY AND
COOL ON SAT. WARMER ON SUNDAY.
DID UP POPS TO 30 PERCENT FROM LATE MONDAY INTO WED MORNING TO
FIT IN WITH OTHERS BETTER. STILL SOME SPREAD ON THE DETAILS. LOOKS
LIKE MODELS AND HPC HAVE COLD FRONT MOVING INTO THE AREA ON TUE.
FRONT MAY NOT CLEAR TO WED. DID UP TEMPERATURES SOME TOO.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
WIDESPREAD IFR/MVFR WILL CONTINUE NORTH OF THE FRONTAL SYSTEM THAT
IS STALLED SOUTH OF PA. THIS STATIONARY FRONTAL BOUNDARY WILL
KEEP LOW LEVEL MOISTURE LOCKED IN PLACE TONIGHT AND THURSDAY.
AREAS OF DRIZZLE WITH SCATTERED SHOWERS WILL BE THE RULE WITH
LITTLE IF ANY IMPROVEMENT EXPECTED.
WINDS WILL REMAIN FROM THE EAST OR SOUTHEAST AT 5-10 MPH THROUGH
THE PERIOD.
OUTLOOK...
FRI...A COLD FRONT WILL BRING MORE REDUCTIONS WITH RAIN SHOWERS
AND POSSIBLE THUNDERSTORMS...ESPECIALLY DURING THE AFTERNOON.
SAT-MON...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/MARTIN
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
110 PM EDT WED APR 8 2015
.SYNOPSIS...
A NEARLY STATIONARY FRONT JUST SOUTH OF PENNSYLVANIA
AND STRONG HIGH PRESSURE OVER QUEBEC WILL COMBINE TO KEEP MOIST
AND COOL CONDITIONS OVER THE REGION THROUGH THURSDAY. A STORM
SYSTEM WILL BRING A COLD FRONT ACROSS PENNSYLVANIA DURING FRIDAY.
MUCH COOLER CONDITIONS WILL FOLLOW FOR SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WE REMAIN FIRMLY ENTRENCHED IN A COOL AIR DAMMING REGIME BETWEEN
STRONG-COLD HIGH PRESSURE OVER SOUTHERN CANADA AND A STATIONARY
FRONT WHICH DOG LEGS FROM WRN PA SOUTH THROUGH WEST VIRGINIA ALL
THE WAY THROUGH SOUTHERN VA BEFORE TURNING EAST AND OFF THE COAST
NEAR THE DEL MARVA.
ALOFT WE ARE ACTUALLY UNDER A FLAT UPPER RIDGE WITH 500 HEIGHTS
THAT ARE SLIGHTLY ABOVE NORMAL FOR THE SEASON. HOWEVER THE FAST
WSW FLOW IS SERVING AS A PATHWAY TO FUNNEL WEAK SHORTWAVES AND
MOISTURE OUR WAY FROM THE LARGE SCALE UPPER TROF OVER THE ROCKY
MOUNTAIN STATES.
THE WARM-MOIST ADVECTION IS PROGGED TO CONTINUE AS THE SURFACE
HIGH TO OUR NORTH STUBBORNLY MAINTAINS A LOW LEVEL EAST OR
SOUTHEAST FLOW. WHILE THE AREA OF MORE ORGANIZED SHOWERS HAS MOVED
OUT OF MY EASTERN ZONES...WE CANNOT RULE OUT THE THREAT FOR MORE
RAIN THROUGH LATE DAY AS THE WEAK LIFT CONTINUES. I EVEN
INTRODUCED A SMALL CHANCE FOR A RUMBLE OF THUNDER. DESPITE HIGH
TEMPS THAT WILL ONLY AVERAGE IN THE 40S OVER MOST OF THE
AREA...MID LEVEL LAPSE RATES ARE SHOWN BY THE RAP TO EXCEED 6C/KM
AS THE MOIST WARM ADVECTION CONTINUES...SO SOME ELEVATED
CONVECTION CANNOT BE RULED OUT.
HIGH TEMPS THIS AFTERNOON WILL AVERAGE IN THE LOW TO MID 40S. FAR
SWRN ZONES MAY BREAK OUT INTO THE MID 50S FOR A SHORT TIME.
CLOUDY...COOL AND DAMP CONDITIONS WILL CONTINUE TONIGHT AS HIGH
PRESSURE OVER QUEBEC CANADA NOSES SWWD INTO THE STATE ACCOMPANIED
BY A LIGHT EAST TO NE BREEZE. THIS SHOULD LEAD TO WIDESPREAD LOW
CLOUDS AND RIDGE-SHROUDING FOG ACROSS MUCH OF THE REGION WITH THE
LOWEST VSBYS ON THE EAST FACING UPPER SLOPES.
MAIN QUESTION WILL CENTER ON HOW MUCH OF THE OHIO CONVECTION CAN
SURVIVE THE TREK INTO OUR WEDGE OF COLD AND STABLE AIR. LATEST
HRRR SHOWS A CLUSTER OF SHOWERS MOVING ACROSS FAR NRN PA THROUGH
EARLY EVENING WHILE THE MAIN MCS/BOW ECHO TRACKS OFF TO OUR SOUTH
TOWARD THE DEEPEST INSTABILITY. FOR MOST OF PA THE HRRR SHOWS THE
CHANCE OF SCATTERED SHOWERS NOT SHOWING ANY PARTICULAR
ORGANIZATION. A BLEND OF MODEL POPS SHOWS PRETTY MUCH A 50-50 COIN
FLIP FOR RAIN IN MOST AREAS OVERNIGHT...BUT THAT SEEMS A PRETTY
ACCURATE REPRESENTATION FOR WHAT IS LIKELY TO OCCUR. ALONG WITH
AREAS OF FOG AND DRIZZLE IT POINTS TO MORE COOL-DAMP CONDITIONS
OVERNIGHT.
LATEST HIGH RES GUIDANCE KEEPS OVERNIGHT LOWS MAINLY IN THE
40S...MINIMIZING THE THREAT FOR POCKETS OF FREEZING DRIZZLE OVER
OUR FAR NERN ZONES THAT WE WERE CONCERNED WITH EARLIER.
&&
.SHORT TERM /THURSDAY/...
THURSDAY LOOKS LIKE A CARBON COPY OF TODAY AS THE HIGH ONLY SLOWLY
RETREATS TOWARD THE CANADIAN MARITIMES. LIFTED INDEX PROGS
INDICATE WE REMAIN STRONGLY DAMMED OVER MOST OF THE AREA
THROUGHOUT THE DAY WHILE WARM MOIST ADVECTION OVER THE LOW LEVEL
COLD WEDGE KEEPS US VULNERABLE TO SCATTERED SHOWERS AND POSSIBLY
AN ELEVATED THUNDERSTORM. HARD TO TIME IN ANY PARTICULAR FEATURE
AT THIS RANGE...AS THIS WILL LIKELY DEPEND ON ANY REMNANTS OF OHIO
VALLEY CONVECTION THAT CAN ORGANIZE IN THE HIGH CAPE AIR IN THE
WARM SECTOR.
HIGHS WILL BE WITHIN A DEGREE OR TOW OF TODAY IN MOST AREAS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
WARMER AIR WILL WORK INTO THE AREA LATE THU INTO FRIDAY...AS LOW
LEVEL WIND FIELDS INCREASE. WARMEST TEMPERATURES MIGHT END UP
BEING ACROSS WARREN COUNTY.
DID NOT UP TEMPS MUCH FOR FRIDAY...MODELS MOVE COLD FRONT ACROSS
THE AREA RATHER FAST.
SOME CHANCE OF A STRONG THUNDERSTORM ACROSS THE WEST LATER FRIDAY.
THIS BASED ON TIMING AND THE THERMAL RIDGE OVER THE BEST MOISTURE.
HAVE TO WATCH FOR SEVERE...BUT DYNAMICS LIKELY TO LIFT NE AWAY
FROM THE AREA. ALSO TIMING NOT THE BEST.
WHILE WE WILL SEE SOME SHOWERS EACH DAY THIS WEEK...NOT SEEING ANY
LARGE AMTS. THUS NOT SEEING ANY WIDESPREAD HYDRO CONCERNS AT THIS
POINT. ENJOY THE MILDER TEMPERATURES.
RATHER STRONG SMALL UPPER LEVEL TROUGH FOR LATE FRIDAY INTO SAT.
TOOK OUT SHOWERS AFTER EARLY FRIDAY EVENING. MAIN THING WAS TO
LOWER TEMPS FOR FRIDAY NIGHT INTO SAT...GIVEN AIRMASS TO THE NORTH
AND COLD ADVECTION.
WEEKEND SIMILAR TO LAST WEEKEND. BREEZY AND COOL ON SAT. WARMER
ON SUNDAY.
DID PUT SOME SHOWERS IN THE FAR WEST LATE MONDAY AND ACROSS THE
AREA ON TUE. MODELS SHOW ANOTHER COLD FRONT MOVING IN.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
WIDESPREAD IFR/MVFR WILL CONTINUE NORTH OF THE FRONTAL SYSTEM THAT
IS STALLED SOUTH OF PA. THIS STATIONARY FRONTAL BOUNDARY WILL
KEEP LOW LEVEL MOISTURE LOCKED IN PLACE TONIGHT AND THURSDAY.
AREAS OF DRIZZLE WITH SCATTERED SHOWERS WILL BE THE RULE WITH
LITTLE IF ANY IMPROVEMENT EXPECTED.
WINDS WILL REMAIN FROM THE EAST OR SOUTHEAST AT 5-10 MPH THROUGH
THE PERIOD.
OUTLOOK...
FRI...A COLD FRONT WILL BRING MORE REDUCTIONS WITH RAIN SHOWERS
AND POSSIBLE THUNDERSTORMS...ESPECIALLY DURING THE AFTERNOON.
SAT-MON...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
511 PM EDT WED APR 8 2015
.SYNOPSIS...
M AND HUMID SOUTHWESTERLY FLOW WILL PERSIST OVER THE REGION THROUGH
THE WORK WEEK...KEEPING CONDITIONS UNSETTLED WITH CHANCES FOR
SHOWERS AND THUNDERSTORMS EACH DAY. A COLD FRONT IS FORECAST TO
CROSS THE REGION BY THE END OF FRIDAY...LIKELY SUPPORTING A BAND OF
SHOWER AND THUNDERSTORMS. DRIER WEATHER IS EXPECTED TO RETURN TO THE
REGION THIS WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 500 PM EDT...THE ATMOS CONTINUES TO BE RATHER SUPPRESSED ACRS
THE CWFA...AS AS UPPER RIDGING DOMINATES. HAVE CUT BACK POP HEADING
INTO THE EVENING HOURS...IN LINE WITH THE LAST FEW HRRR RUNS OF
SIMULATED REFLECTIVITY. MCS ACTIVITY LOOKS TO REMAIN NORTH OF THE
AREA. HOWEVER...ONE CLUSTER OF STORMS OVER CENTRAL KY MAY DROP SE IN
TO THE NC MTNS LATE THIS EVENING (PER THE CONVECTION ALLOWING
MODELS). SO WILL LEAVE THE CHC POP ACRS THE NRN TIER FOR LATE
EVENING INTO OVERNIGHT. THE UPSTATE AND NE GA MAY NOT SEE ANY
PRECIP...IF THE LATEST TRENDS HOLD.
AS OF 230 PM EDT...WEAK UPPER RIDGING CONTINUES TO STRENGTHEN DOWN
THE EASTERN SEABOARD IN RESPONSE TO A DIGGING UPPER TROUGH ACROSS
THE ROCKIES. STRONG SHORTWAVE CROSSING THE FLOW ACROSS THE CENTRAL
APPALACHIANS IS RESULTING IN A FAIRLY SIGNIFICANT CONVECTIVE COMPLEX
MOVING INTO WEST VIRGINIA AT AFD TIME. HI-RES REFLECTIVITY GUIDANCE
WANTS TO CONTINUE TO DRAG THIS COMPLEX SOUTHEAST ALONG THE NORTHWEST
FLOW ALOFT...CLIPPING THE NORTHERN PORTION OF OUR FORECAST AREA.
SBCAPE VALUES EAST OF THE RIDGES CONTINUE TO INCREASE AND ARE UP TO
BETWEEN 1000-1500 J/KG AT AFD TIME AND LOOK TO SUPPORT THE
SUSTAINING OF THIS COMPLEX. ADDITIONALLY...WITH THE INCREASING
SBCAPE VALUES...CANNOT RULE OUT AT LEAST ISOLATED CONVECTION
ELSEWHERE ACROSS THE AREA THIS AFTERNOON AND EVENING AS THE LOW
LEVEL CAP ERODES. BUFR SOUNDINGS MAX OUT BETWEEN 1500-2000 J/KG AT
VARIOUS LOCATIONS ACROSS THE FORECAST AREA AND WITH SLIGHTLY STEEPER
LAPSE RATES THAN YESTERDAY...CERTAINLY CANNOT RULE OUT ISOLATED
SEVERE THOUGH BEST CHANCES REMAIN ACROSS EXTREME NORTHERN ZONES
CLOSER TO THE UPPER SHORTWAVE. THREATS SIMILAR TO YESTERDAY WITH
LARGE HAIL AND DAMAGING WINDS.
UPPER RIDGING WILL CONTINUE TO INCREASE OVERNIGHT BUT COULD STILL
SEE ANOTHER ROUND OF LOW CLOUDS AND LIGHT FOG THURSDAY MORNING. THE
ROCKIES UPPER WAVE WILL PUSH INTO THE PLAINS DURING THE DAY ON
THURSDAY...DRAGGING A FRONT THROUGH THE MID MISSISSIPPI VALLEY. WE
REMAIN SOLIDLY IN THE WARM SECTOR ACROSS THE SOUTHEAST WITH BOTH GFS
AND NAM INCREASING CAPES ACROSS ESPECIALLY THE PIEDMONT TO BETWEEN
1500-2000 J/KG AGAIN. NO REAL DEEP LAYER BULK SHEAR TO SPEAK
OF...TOO FAR AHEAD OF THE UPPER SYSTEM...BUT THERE IS ENOUGH TURNING
IN THE WIND PROFILE WITH THE SOUTHERLY WINDS AT THE SURFACE AND WEST
TO SOUTHWESTERLY WINDS ALOFT TO RESULT IN SOME DECENT HELICITY
VALUES THAT MAY HELP TO ORGANIZE CONVECTION THURSDAY AFTERNOON INTO
EVENING. CURRENT SPC DAY2 OUTLOOK ONLY HAS OUR AREA IN GENERAL
THUNDER BUT WOULD NOT BE SURPRISED TO AGAIN SEE ISOLATED SEVERE
POTENTIAL. POPS THROUGH THE NEAR TERM CONTINUE TO FOLLOW A GENERAL
DIURNAL TREND BUT HIGHER POPS ARE EMPHASIZED ACROSS NORTHERN ZONES
CLOSER TO ANY SHORTWAVE ACTIVITY.
TEMPERATURES REMAIN WARM UNDER THE INCREASING THICKNESSES ALOFT...
WITH LOWS TONIGHT A GOOD 10-15 DEGREES ABOVE NORMAL AND HIGHS
THURSDAY 10 OR SO DEGREES ABOVE SEASONAL NORMALS. GUIDANCE OVERALL
IN FAIRLY GOOD AGREEMENT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 215 PM WEDNESDAY...THE MAIN FOCUS FOR THE SHORT TERM CONTINUES
TO BE THE POTENTIAL FOR SEVERE THUNDERSTORMS AHEAD/ALONG A COLD
FRONT MAINLY IN THE AFTERNOON. BUT BEFORE WE GET THERE...WE WILL
STILL HAVE TO DEAL WITH A CHANCE OF THUNDERSTORMS...PERHAPS A FEW
STRONG TO SEVERE...ON THURSDAY EVENING. THE WHOLE FCST AREA WARRANTS
A CHANCE POP INTO THURSDAY EVENING...BUT LOSS OF DAYTIME HEATING
SHOULD REDUCE THE CHANCES BACK TO WHERE SOME MECHANICAL FORCING
REMAINS IN THE VICINITY OF THE BLUE RIDGE BY LATE EVENING. THE
PRECIP CHANCES THEN START RAMPING UP ON THE TN BORDER AFTER MIDNIGHT
AS CONVECTION ALONG A PRE-FRONTAL TROF MAY REACH THE NC MTNS BEFORE
DAYBREAK. EXPECT AREAS E OF THE MTNS TO GET A BREAK IN THE ACTION
AROUND SUNRISE FRIDAY...WHICH RESULTS IN A SHORT PERIOD WITH A LARGE
POP GRADIENT FROM W TO E. TEMPS SHOULD BE SEASONALLY MILD OVERNIGHT.
WHICH BRINGS US TO FRIDAY. THE MODELS SHOW EXCELLENT FORCING ALONG
THE FRONT TO THE WEST DURING THE EARLY MORNING HOURS...BUT THIS
WEAKENS AS IT CROSSES THE WESTERN CAROLINAS. THE RECENT MODEL TREND
SHOWING POORER CONVERGENCE ACROSS THE FRONT ALSO CONTINUES ON THE
NEW RUNS. THE CORE OF THE LOW LEVEL JET PULLS NWD BY AFTERNOON AND
850 MB WINDS WEAKEN AND VEER. THE RESULT IS SOMEWHAT WEAKER SHEAR
AND A MORE UNIDIRECTIONAL HODOGRAPH. ON THE OTHER HAND...A SLIGHT
DELAY IN THE TIMING ALLOWS SURFACE BASED CAPE IN THE MODELS TO CLIMB
A BIT HIGHER...CLOSER TO 1000 J/KG ON THE GFS AND ABOVE 1500 J/KG ON
THE OPERATIONAL NAM. SO...THE TREND ON THE SIGNALS IS MIXED. STILL
THINK WE HAVE A DECENT CHANCE FOR ORGANIZED SEVERE CONVECTION...
ESPECIALLY E OF THE MTNS...SO WE WILL CONTINUE TO MENTION IT IN THE
HWO. THE PRECIP PROBABILITY GOES UP TO CATEGORICAL ON THE TN
BORDER...BUT HAVE KEPT ONLY A LIKELY E OF THE MTNS BECAUSE IT IS
POSSIBLE THAT A CONVECTIVE LINE COULD BREAK UP A BIT OVER THE MTNS
AND THEN FILL BACK IN AS IT IS LEAVING THE EASTERN PART OF THE FCST
AREA LATE IN THE DAY. THE CONVECTION SHOULD PUSH E OF THE REGION IN
THE EARLY EVENING EVEN IF THE FRONT GETS HELD UP ON THE MTNS. PRECIP
CHANCES RAMP DOWN FROM THE WEST WITH FRONTAL PASSAGE.
ON SATURDAY...A NRN STREAM TROF PASSING TO THE WEST WILL RESULT IN A
NEARLY ZONAL FLOW ACROSS THE SOUTHEAST. HIGH PRESSURE SHOULD BUILD
IN TO DRY US OUT AND GIVE US A NORMAL SPRING DAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 215 PM WED...GUIDANCE IN GENERAL AGREEMENT WITH SHORT WAVE
RIDGING SETTING UP FOR SUNDAY AND MONDAY AS A SRN STREAM UPPER LOW
DEVELOPS AND MOVES INTO THE SRN PLAINS. AHEAD OF THIS SYSTEM...A
DAMPENING SHORT WAVE TOPS THE RIDGE AND CROSSES THE AREA TUE AS THE
UPPER LOW WEAKENS AND MOVES INTO THE GREAT LAKES. RIDGING BEGINS TO
REBUILD ON WED...BUT SWLY FLOW ALOFT REMAINS OVER OUR AREA WITH WEAK
SHORT WAVES MOVING THRU THE FLOW.
AT THE SFC...DRY AND MILD HIGH PRESSURE MOVES IN ON SUN...WITH
POTENTIALLY ENUF LINGERING MOISTURE FOR ISOLATES SHOWERS ACROSS THE
MTNS. TEMPS WILL BE UP TO 5 DEGREES ABOVE NORMAL. THE HIGH MOVES
EAST MON WITH SLY RETURN FLOW DEVELOPING. WITHOUT ANY STRONG FORCING
DEVELOPING...EXPECT SCT SHRA ACROSS THE MTNS AND ISOLATED SHRA
ELSEWHERE. TEMPS 5 TO 10 DEGREES ABOVE NORMAL. THE SLY RETURN FLOW
REMAINS IN PLACE TUE AND WED WITH WEAK SFC RIDGING OVER THE AREA AND
ANY FRONTAL SYSTEMS WELL TO OUR NORTH. THIS WILL CREATE SCT MAINLY
DIURNAL CONVECTION BOTH DAYS. LOWS WILL BE UP TO 15 DEGREES ABOVE
NORMAL WITH HIGHS AROUND 10 DEGREES ABOVE NORMAL.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...STUBBORN MVFR CIGS ARE BEGINNING TO LIFT AND SCATTER AND
EXPECT VFR CONDITIONS THIS AFTERNOON WITH SW WINDS GENERALLY
REMAINING 7KT OR LESS. AN UPPER LEVEL DISTURBANCE PASSES TO THE
NORTH OF THE AREA LATE THIS AFTERNOON AND EVENING AND HAVE
INTRODUCED TEMPO TSRA FROM 23-03Z TO ACCOUNT FOR PROXIMITY...BUT IT
IS VERY POSSIBLE THAT ALL TSRA WILL STAY NORTH OF KCLT. AS THE
DISTURBANCE APPROACHES...WINDS WILL BACK MORE TO THE S WITH SPEEDS
DECREASING. POTENTIAL FOR RESTRICTED VSBYS/CIGS THURSDAY MORNING
HIGHLY DEPENDENT ON COVERAGE OF CONVECTION LATER TODAY BUT OVERALL
CANNOT RULE OUT A REPEAT OF THIS MORNING. HAVE BROUGHT IN MVFR VSBY
BUT ONLY SCT IFR CLOUDS FOR NOW. IMPROVING CONDITIONS AFTER SUNRISE
THURSDAY.
ELSEWHERE...VERY SIMILAR TO KCLT OVERALL. KHKY HAS THE BEST CHANCE
OF LATE AFTERNOON/EVENING CONVECTION WITH KAND THE LEAST...OPTED TO
NOT INTRODUCE TEMPO TSRA AT KAND FOR NOW. AS WITH KCLT...COULD SEE
PATCHY IFR CIGS AND AT LEAST MVFR VSBY THURSDAY MORNING BUT OVERALL
RESTRICTIONS WILL DEPEND HIGHLY ON COVERAGE OF EVENING CONVECTION.
IMPROVING AFTER SUNRISE THURSDAY.
OUTLOOK...EXPECT ANOTHER ROUND OF AFTERNOON CONVECTION THURSDAY
AFTERNOON/EVENING...AND A COLD FRONT WILL PUSH THROUGH LATE FRIDAY
ALSO WITH THE POTENTIAL FOR AT LEAST SCATTERED CONVECTION. WITH
AFTERNOON CONVECTION WILL FOLLOW POTENTIAL FOR RESTRICTIONS EACH
MORNING. MUCH IMPROVED CONDITIONS FOR THE WEEKEND AFTER THE FRONT
CLEARS THE AREA.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-18Z
KCLT HIGH 100% HIGH 94% HIGH 94% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 94% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 89% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 94%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...ARK/TDP
SHORT TERM...PM
LONG TERM...RWH
AVIATION...TDP
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
346 PM CDT WED APR 8 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 346 PM CDT WED APR 8 2015
PERSISTENT LOW CLOUD EVENT EXPECTED TO CONTINUE ACROSS THE AREA
TONIGHT INTO TOMORROW AS LOW LEVEL EASTERLY FLOW REINFORCES STRATUS
ACROSS THE AREA. BAD OF 850 HPA THETA-E ADVECTION IS EXPECTED TO
LIFT NORTH THROUGH THE LATE AFTERNOON INTO THE EVENING HOURS. STILL
SOME QUESTION AS TO HOW CONVECTIVE ANY ACTIVITY MAY GET AS VERY
STEEP LAPSE RATES EXIST FROM 700-300 MB ACROSS THE SOUTHEASTERN CWA.
RAP SOUNDINGS SHOW SMALL WARM NOSE HOLDING...BUT NOT SURE AM READY
TO BUY INTO THAT ENTIRELY SO HAVE HELD ON TO THE MENTION OF THUNDER
THROUGH THE LATE AFTERNOON. WITH STEEP LAPSE RATES AND COLD
ATMOSPHERE...CERTAINLY A GOOD CASE FOR HAIL IF A STORM CAN DEVELOP
FROM THE ELEVATED WARM AIR AND MOISTURE ADVECTION.
ISENTROPIC LIFT CONTINUES THROUGH THE OVERNIGHT THOUGH CONTINUE TO
HAVE OFF AND ON SATURATION ISSUES ALOFT. THEREFORE...AM EXPECTING
LIGHT RAIN OR DRIZZLE THROUGH THE EVENING HOURS...INCREASING AFTER
MIDNIGHT AS THE DEFORMATION BAND APPROACHES FROM THE WEST.
AS THE SURFACE COLD FRONT/INVERTED TROUGH MOVES THROUGH THE
AREA...FLOW TURNS MORE NORTHERLY WITH WARM NOSE ALOFT COOLING.
THERE IS THE POTENTIAL FOR A FEW FLAKES TO MIX IN WITH THE RAIN
TOMORROW DURING THE DAY...ESPECIALLY IN THE HIGHER ELEVATIONS...BUT
WITH THE WARM LAYER NEAR THE SURFACE REMAINING STEADY THROUGH THE
DAY...AM NOT EXPECTING SNOW TO ACCUMULATE. HAVE LOWERED FORECAST
HIGHS ACROSS THE EAST WITH PRECIPITATION LINGERING THROUGH MUCH OF
THE DAY...WHILE SKIES SHOULD BEGIN TO CLEAR OUT IN CENTRAL SOUTH
DAKOTA THROUGH THE AFTERNOON HOURS LEADING TO A LATE DAY RECOVERY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 346 PM CDT WED APR 8 2015
COULD SEE A LITTLE PRECIP LINGERING IN OUR FAR EAST INTO THURSDAY
EVENING...BUT OTHERWISE EXPECT GENERALLY DRY CONDITIONS TO PREVAIL
THROUGH THE MIDDLE RANGE OF THE FORECAST AS MID LEVEL RIDGE MOVES
ACROSS THE NORTHERN PLAINS. AS THE RIDGE AXIS SHIFTS EAST INTO IOWA
AND MINNESOTA LATE SATURDAY/SATURDAY NIGHT...RETURN FLOW OF MOISTURE
AND WEAK ELEVATED INSTABILITY COULD LEAD TO SOME ISOLATED SHOWERS OR
THUNDERSTORMS. THIS CHANCE WILL LINGER IN THE EAST INTO SUNDAY AS
THE MID LEVEL TROUGH AND ASSOCIATED SURFACE FRONT PUSH THROUGH THE
AREA. TEMPERATURES WILL BE ON A WARMING TREND AGAIN...WITH MID 50S
TO MID 60S EXPECTED FOR HIGHS ON FRIDAY...AND UPPER 60S TO MID 70S
BY SATURDAY.
THE MILD AIR WILL STICK AROUND THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...THOUGH WITH THE DIVERGENCE IN MODEL SOLUTIONS BY TUESDAY AND
WEDNESDAY...THERE IS SOME UNCERTAINTY ON JUST HOW WARM TEMPERATURES
WILL BE. OPTED TO STICK FAIRLY CLOSE TO BROAD MODEL BLEND FOR NOW...
WHICH KEEPS HIGHS IN THE MID 60S TO MID 70S AND LOWS IN THE 40S TO
LOWER 50S.
AS FAR AS PRECIP CHANCES...IT CURRENTLY LOOKS LIKE SUNDAY NIGHT TO
MONDAY SHOULD BE FAIRLY DRY AS THE NORTHERN STREAM TROUGH SHIFTS TO
THE EAST...AND WEAK RIDGING DEVELOPS AHEAD OF A SOUTHERN STREAM WAVE
THAT IS FORECAST TO SWING INTO THE PLAINS FROM THE SOUTHERN ROCKIES
MONDAY NIGHT. THIS WILL BRING A BIT MORE UNSETTLED WEATHER TO THE
AREA MONDAY NIGHT/TUESDAY. GREATER UNCERTAINTY REGARDING THE CHANCE
FOR PRECIP TUESDAY NIGHT/WEDNESDAY DUE TO AFOREMENTIONED DIVERGENCE
IN MODEL SOLUTIONS. WITH LOW CONFIDENCE IN ANY ONE SOLUTION...WILL
HANG ON TO SOME LOW 20-30 RANGE POPS FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1229 PM CDT WED APR 8 2015
PERSISTENT LOW LYING STRATUS SHOULD CONTINUE TO REMAIN ACROSS THE
AREA THROUGH THE FORECAST PERIOD. COULD SEE PERIODS OF RAIN AND
DRIZZLE...REDUCING VISIBILITY. WINDS ARE EXPECTED TO INCREASE OUT
OF THE NORTH LATE IN THE PERIOD AS A COLD FRONT DROPS FROM
NORTHWEST TO SOUTHEAST.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...JH
AVIATION...
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
614 PM EDT WED APR 8 2015
.DISCUSSION...QUICK UPDATE BASED ON PRESENT CONDITIONS AND HI-RES
MODELS.
CAP CURRENTLY WINNING BATTLE AS DEEP CONVECTION STAYING TO
THE NORTH. RAP SOUNDING SHOWING WARM LAYER AT 700MB THAT NAM IS NOT
SHOWING. MODELS GENERALLY AGREE THAT 700MB WARM ADVECTION IS
OCCURRING...SO THINK THAT CAP WILL CONTINUE TO KEEP MOST CONVECTION
TO THE NORTH. HOWEVER...AROUND 04Z-08Z RAP 700MB TEMP MAP SHOWS
THERMAL TROUGH PUSHING THRU NE SECTIONS FROM NW-SE. SO BEST CHANCES
OF CAP WEAKENING IN THAT AREA DURING THAT TIME PERIOD. CURRENT POP
GRADIENT PATTERN LOOKS GOOD...BUT WILL LOWER POPS IN GENERAL...BUT
KEEPING HIGHEST POPS IN THE NORTHEAST. WILL KEEP MENTION OF
THUNDER. 850MB LOW LEVEL JET WILL BE INCREASING...BUT ALONG WITH
THE CAP...SO LOOKS LIKE MOST OF THIS INCREASED TRANSPORT WILL BE
GOING INTO DEEP CONVECTION MAINLY NORTH.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 64 83 64 72 / 10 20 90 90
KNOXVILLE MCGHEE TYSON AIRPORT, TN 62 82 64 70 / 10 20 70 90
OAK RIDGE, TN 63 82 63 70 / 10 20 80 90
TRI CITIES AIRPORT, TN 56 81 60 70 / 30 30 70 90
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
GM
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1203 PM CDT WED APR 8 2015
.UPDATE... /ISSUED 1014 AM CDT WED APR 8 2015/
SKIES ARE MOSTLY SUNNY OVER MUCH OF THE FORECAST AREA THIS
MORNING WITH TEMPERATURES IN THE 70S. SOME ISOLATED SHOWERS
CONTINUE TO MOVE OVER NORTHERN SECTIONS OF THE FORECAST AREA BUT
THIS ACTIVITY IS JUST ABOUT DONE. SOME ISOLATED THUNDERSTORMS MAY
MOVE THROUGH NORTHERN SECTIONS OF THE FORECAST AREA THIS
AFTERNOON. WILL SEND AN UPDATE TO THE FORECAST TO REMOVE MORNING
WORDING.
ARS
.DISCUSSION... /ISSUED 608 AM CDT WED APR 8 2015/
AS OF 4AM...TEMPERATURES ARE MILD ONCE AGAIN THIS MORNING WITH
READINGS MAINLY IN THE MID TO UPPER 60S ACROSS THE REGION. EARLIER
CONVECTION NEAR THE SOUTHERN KANSAS/MISSOURI BORDER HAS WEAKENED
SIGNIFICANTLY IN THE LAST COUPLE OF HOURS WITH ONLY LIGHT SHOWERS
DEVELOPING TO THE SOUTH OF THE LEFTOVER COMPLEX. A BROAD AREA OF
SCATTERED SHOWERS AND THUNDERSTORMS WERE MOVING OVER PORTIONS OF
CENTRAL AND NORTHEAST ARKANSAS ASSOCIATED WITH A WEAK SHORTWAVE
EMBEDDED IN THE MEAN FLOW. WATER VAPOR IMAGERY ALSO SHOWS A LARGE
CUTOFF LOW ROTATING OVER THE GREAT BASIN THIS MORNING. THIS
FEATURE WILL BE MAIN WEATHER MAKER ACROSS OUR AREA OVER THE NEXT
48 HOURS OR SO.
SHORT TERM...TODAY THROUGH FRIDAY...
THE HRRR HI-RES SHORT TERM MODEL INDICATES THAT SHOWERS AND
SCATTERED THUNDERSTORMS WILL MOVE THROUGH THE MID-SOUTH AGAIN
THIS MORNING. COVERAGE IS EXPECTED TO LESS THAN YESTERDAY...BUT
WILL STILL WARRANT A 20 POP. BY EARLY AFTERNOON...SHOWERS WILL
EXIT THE AREA AND SLIGHT UPPER LEVEL RIDGING WILL RESULT IN
CLEARING SKIES AND VERY WARM CONDITIONS FOR THIS TIME OF YEAR.
READINGS WILL BE IN THE LOW TO MID 80S THIS AFTERNOON...WHICH IS
AS MUCH AS 15 DEGREES ABOVE THE CLIMATOLOGICAL NORMAL FOR THIS
TIME OF YEAR AND NEAR RECORD HIGHS.
BY LATE TONIGHT...MODELS ARE IN REASONABLE AGREEMENT THAT THE
UPPER LEVEL CLOSED LOW OUT WEST WILL EVOLVE INTO AN OPEN WAVE AS
IT MOVES ACROSS THE ROCKIES...AND SURFACE LOW PRESSURE WILL
DEVELOP NEAR THE OKLAHOMA PANHANDLE. THIS SURFACE LOW WILL MOVE
ACROSS THE CENTRAL PLAINS AND INTO THE GREAT LAKES REGION FROM
THURSDAY MORNING AND INTO FRIDAY. AS IT DOES...A STRONG COLD FRONT
WILL SWEEP ACROSS THE MISSISSIPPI VALLEY AND INTERACT WITH A
MODERATELY UNSTABLE AIRMASS. MLCAPE VALUES APPROACHING 2000 J/KG
AND A 50 KT MID LEVEL JET WILL SUPPORT AT LEAST A FEW STRONG TO
SEVERE STORMS. STORM MODE IS STILL A LITTLE UNCLEAR AT THE
MOMENT...BUT IT DOES APPEAR SOME STORMS COULD DEVELOP AHEAD OF THE
LINE AS HEIGHT FALLS OVERSPREAD THE REGION...BEFORE CONGEALING
INTO A QLCS STRUCTURE BY LATE THURSDAY EVENING. DAMAGING WINDS AND
LARGE HAIL LOOK TO BE THE MAIN THREATS...WITH A SECONDARY THREAT
OF FLASH FLOODING. TORNADO THREAT LOOKS VERY MINIMAL...AS THE
FAVORABLE JET STRUCTURE REMAINS WELL TO OUR NORTH. WILL CONTINUE
TO MAKE A MENTION OF SEVERE STORMS IN THE HWO WITH THE BEST
CHANCES REMAINING OVER NORTHEAST ARKANSAS...THE MISSOURI
BOOTHEEL...AND PORTIONS OF NORTHWEST TENNESSEE.
BY FRIDAY AFTERNOON...THE FRONT WILL PUSH TO THE SOUTH AND EAST
AS SURFACE HIGH PRESSURE BUILDS IN. TEMPERATURES WILL BE MILD
DURING THE DAY WITH UPPER 60S AND LOWER 70S EXPECTED.
SATURDAY WILL BE A BEAUTIFUL MILD SPRING DAY WITH LOW HUMIDITY...
TEMPERATURES IN THE LOWER 70...AND ABUNDANT SUNSHINE.
LONG TERM...SUNDAY THROUGH EARLY NEXT WEEK...
A STALLED COLD FRONT TO OUR SOUTH WILL PUSH NORTH AS A WARM FRONT
ON SUNDAY MORNING. AS IT DOES...SHOWERS AND THUNDERSTORMS WILL
OVERSPREAD THE REGION BY THE AFTERNOON HOURS. SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO CONTINUE ON MONDAY BEFORE A COLD
FRONT PUSHES THROUGH THE MID-SOUTH BY TUESDAY. CHANCES FOR SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO MIDWEEK AS RETURN FLOW
REMAINS DOMINANT ACROSS THE REGION.
AC3
&&
.AVIATION...
18Z TAF SET
VFR CONDITIONS EXPECTED THROUGH MUCH OF THE NEXT 24 HOURS. THE
ONLY EXCEPTION MAY BE BETWEEN 09-15Z WHEN STRATUS MAY MOVE UP OVER
THE AREA FROM THE SOUTH LOWERING CIGS TO MVFR. ALSO INTRODUCED
VCTS WORDING AT KJBR BETWEEN 9Z-13Z FOR REMNANT TSRAS THAT MAY
PUSH IN FROM SOUTHERN M0. STRONG S TO SSW WINDS WILL CONTINUE OVER
THE AREA OVER THE NEXT 24 HOURS. SPEEDS WILL GENERALLY BE BETWEEN
10-15 KTS WITH HIGHER GUSTS AT TIMES.
KRM
&&
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
347 PM CDT WED APR 8 2015
.SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
OVERALL HIGHLIGHTS FOR THIS PERIOD WILL FOCUS ON THE ISOLATED TO
SCATTERED STRONG TO SEVERE STORM POSSIBILITIES THURSDAY AFTERNOON
INTO THURSDAY EVENING FOR AREAS GENERALLY ALONG AND NORTH OF A
FREDERICKSBURG TO LA GRANGE LINE.
FOR TODAY...WATER VAPOR IMAGERY CHANNELS DEPICT A SHORTWAVE TROUGH
OVER UTAH WITH RAP ANALYSIS INDICATING AN ENHANCED MID-LEVEL WIND
SPEED BELT EXTENDING INTO SOUTH-CENTRAL TEXAS BACK WESTWARD INTO
NORTHERN MEXICO. THE INCREASING H5-H3 WIND FLOW IS AIDING IN
BETTER DIVERGENCE ALOFT AND HELPING GENERATE SOME ELEVATED SHOWERS
ABOVE A CAPPING INVERSION. 315K THETA SURFACE DEPICTS LOWEST
CONDENSATION PRESSURE DEFICITS WITH LOWER LAYERS STILL DRY. THIS
IS LIMITING OVERALL AMOUNTS FROM REACHING THE GROUND SO FAR THIS
AFTERNOON. THIS BIG QUESTION FOR LATE AFTERNOON WILL BE HOW MUCH
CLOUD COVER EROSION OCCURS WHICH COULD ALLOW FOR MORE SURFACE
HEATING AND POSSIBLY AID SURFACE BASED STORMS OUT WEST. VIS
SATELLITE TRENDS SHOW CLEARING ACROSS MAVERICK BUT VAL VERDE
REMAINS MOSTLY SOCKED IN. SOME ADDITIONAL CLEARING IS EXPECTED
ACROSS THE NORTHERN RIO GRANDE PLAINS THROUGH 6PM BUT BOTH GFS/NAM
FORECAST SOUNDINGS SUGGEST OVERALL CAP SHOULD HOLD AND LIMIT
SURFACE BASED CONVECTIVE POTENTIAL. DESPITE THIS FACT...ELEVATED
INSTABILITY WILL GROW AS CAPPING INVERSION THINS ABOVE 700MB.
WHILE AN ISOLATED STRONG STORM CAPABLE OF SMALL HAIL OR WIND GUSTS
TO 40 MPH CAN NOT BE ENTIRELY RULED OUT THROUGH THIS EVENING...THE
CHANCES ARE RELATIVELY LOW. OVERNIGHT...EXPECT SOME LINGERING
SHOWERS ACROSS THE RIO GRANDE PLAINS WITH SOUTHEASTERN AREAS
MOSTLY DRY.
FOR THURSDAY...THE SHORTWAVE TROUGH OVER UTAH WILL HELP PUSH A
WEAK FRONT TOWARDS THE REGION THAT WILL IMPINGE ON THE
DRYLINE TO EDGE TOWARDS THE HILL COUNTY BY THE AFTERNOON. AFTER
MORNING CLOUD COVER SLOWLY ERODES...SURFACE INSTABILITY IS
PROGGED TO INCREASE TOWARDS 3000 J/KG AS MIXING OCCURS BY MID
AFTERNOON. BOTH NAM/GFS BUFR SOUNDINGS INDICATE THE EROSION OF THE
CAP ACROSS NORTHERN AREAS WITH 30KT 0-6 KM SHEAR IN PLACE. WHILE
NOT SUPER HIGH...THIS AMOUNT IN CONJUNCTION WITH A LOW-LEVEL
FORCING BOUNDARY (DRYLINE) COULD HELP SUPPORT SOME ISOLATED TO
SCATTERED STORMS THAT COULD TAKE ON A SUPERCELL APPEARANCE. MOST
FAVORED AREAS WILL BE TOWARDS WACO TO DALLAS WITH TAIL END CELLS
POSSIBLE TO SKIRT BURNET TO WILLIAMSON. QUARTER SIZED HAIL AND
WIND GUSTS TO 60 MPH WILL BE PRIMARY THREATS. THIS ACTIVITY WILL
WANE THROUGH THE MID EVENING HOURS AS INSTABILITY DECREASES BUT
MID-LEVEL SHOWERS COULD REGENERATE LATE THURSDAY INTO FRIDAY AS AN
IMPULSE MOVES OVER THE REGION FROM THE WEST. /ALLEN/
&&
.LONG TERM (FRIDAY THROUGH WEDNESDAY)...
AN UNSETTLED PATTERN WILL BE IN PLACE FRIDAY THROUGH NEXT WEEK AS
AREA WILL REMAIN IN SW FLOW WITH EMBEDDED IMPULSES TRAVERSING THE
REGION. THERE WILL BE A CHANCE OF STRONG TO SEVERE STORMS FRIDAY
AND POCKETS OF HEAVY RAIN OVER THE WEEKEND.
FOR FRIDAY...THE WEAK BOUNDARY/DRYLINE WILL BE LOCATED OVER THE
NORTHERN HALF OF THE REGION LEAVING SOUTHERN LOCATIONS IN A MORE
UNSTABLE AIRMASS BY FRIDAY AFTERNOON. THE QUESTION FRIDAY WILL BE
HOW MUCH INSTABILITY WILL OCCUR GIVEN CLOUD COVER FROM MID-LEVEL
LIFT FROM A MORNING TRAVERSING IMPULSE. GLOBAL MODELS INDICATE
RENEWED CONVECTION DURING THE AFTERNOON PER MASS FIELDS WHICH
INCREASES CONFIDENCE OF MORE SURFACE BASED ACTIVITY. SUPPORTIVE
LAPSE RATES AND SHEAR APPEAR TO BE IN PLACE FOR SOME ISOLATED STRONG
TO SEVERE STORMS WITH MORE FAVORED AREA ACROSS WESTERN AND
SOUTHERN ZONES.
FOR THE WEEKEND...THE BOUNDARY WILL WASH OUT WITH REESTABLISHING
SE LOW-LVL FLOW UNDERNEATH CONTINUED ZONAL TO SW FLOW AS EMBEDDED
IMPULSES TRAVERSE THE REGION. THESE IMPULSES IN COMBINATION WITH
INSTABILITY AND AT LEAST MODEST H5 WIND SPEEDS SHOULD HELP AT
LEAST SCATTERED SHOWER AND THUNDERSTORM GENERATION SATURDAY AND
SUNDAY AFTERNOON. THESE IMPULSES WILL BE EJECTING AHEAD OF A
LARGER CUT-OFF H5 LOW ACROSS NORTHERN MEXICO THAT WILL AID IN
SURFACE LOW DEVELOPMENT INTO MONDAY MORNING ACROSS NORTHERN TEXAS.
FOR EARLY NEXT WEEK...THE NEGATIVELY TILTED TROUGH FROM THE MAIN
LOW WILL PIVOT ACROSS THE REGION AND AID IN LIKELY CONTINUED
SHOWER AND THUNDERSTORM ACTIVITY. BOTH GFS AND EC PRECIP RUN
ACCUMULATION TOTALS SUGGEST POCKETS OF 4-5 INCHES THROUGH THE END
OF NEXT WEEK. TRENDS WILL NEED TO MONITORED EACH DAY FOR POSSIBLE
FLOODING CONCERNS IF A MORE CONCENTRATED COMPLEX DEVELOPS. /ALLEN/
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 69 85 66 77 64 / 20 30 30 50 50
AUSTIN BERGSTROM INTL AIRPORT 68 83 66 77 64 / 20 30 30 50 50
NEW BRAUNFELS MUNI AIRPORT 68 85 67 79 65 / 20 20 10 50 50
BURNET MUNI AIRPORT 66 84 63 74 62 / 30 40 30 50 50
DEL RIO INTL AIRPORT 68 89 69 83 67 / 30 - 20 50 50
GEORGETOWN MUNI AIRPORT 68 84 64 75 63 / 30 40 40 50 50
HONDO MUNI AIRPORT 68 86 68 80 66 / 30 10 10 50 50
SAN MARCOS MUNI AIRPORT 69 84 66 78 65 / 20 20 20 50 50
LA GRANGE - FAYETTE REGIONAL 70 84 69 80 67 / 10 20 20 50 50
SAN ANTONIO INTL AIRPORT 69 85 69 79 66 / 20 10 10 50 50
STINSON MUNI AIRPORT 69 86 69 80 67 / 20 10 10 50 50
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...01
SYNOPTIC/GRIDS...15
PUBLIC SERVICE/DATA
COLLECTION...33
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
331 PM CDT Wed Apr 8 2015
.SHORT TERM...
(Tonight and Tomorrow)
Initial shortwave has worked itself off to the east and has taken
the first round of mainly elevated convection with it. A little more
potent shortwave is approaching for late this afternoon and this
evening. At the surface, a fairly diffuse dryline extends across the
Permian Basin northward into the Panhandle. Much sharper feature to
the north where the high clouds have thinned enough to allow much
better mixing and a more defined dryline.
Morning soundings showed a substantial cap to overcome for surface
based convection, and the abundant high clouds limiting sunshine and
heating has so far not weakened the cap enough. However, as the
shortwave approaches, should see the cap finally weaken enough to
see at least scattered convection develop from the Permian Basin
north into the South Plains, with the activity spreading into West
Central Texas by sunset. How much convection we see is still a
question, with the HRRR showing a fairly extensive area of storms
while the TTU WRF shows quite a bit less. Given the shear and at
least some instability, if storms can develop and get organized,
they certainly have the potential to reach severe levels. And given
a 50 kt low level jet developing during the evening, storms may be
slow to dissipate through the evening and into the early morning
hours.
Pacific front shifts east into West Central Texas on Thursday,
although perhaps not quite clearing the eastern sections by
afternoon. May have enough moisture still in place for a few storms
to redevelop across areas of a Brownwood to Junction line.
.LONG TERM...
(Thursday Night through Wednesday)
Rain chances will continue Thursday night over southern sections
of the forecast where the frontal boundary will be located. The
frontal boundary will continue to provide a focus of thunderstorm
activity Friday and into the weekend as low level winds return to
south and southeasterly allowing isentropic upglide across over
the area. The best chance of additional rainfall will be over the
southern half of the area. Winds aloft will become southwesterly
ahead of an upper level low that will move across the northern
Baja Peninsula Saturday night. Periodic disturbances in the flow
aloft will keep the chance of thunderstorms over the area through
Sunday night. Rain chances will decrease over most of the CWA
from west to east on Monday as the Pacific upper low lifts
northeast from extreme western Texas to the Central Plains.
Residual thunderstorms will still be possible over primarily the
southern CWA through Wednesday as a southwestern flow aloft
reestablishes ahead of another upper level low digging southeast
from the Pacific Northwest to the Central Rockies.
Post-frontal afternoon temperatures on Friday will be in the
lower 70s across the forecast area after Friday morning lows in
50s. Given the continuation of rainfall chances and good cloud
cover through the middle of next week, warm-up will be gradual
with upper 70s for Saturday highs, upper 70s and lower 80s on
Sunday and Monday, and lower 80s for highs on Tuesday and
Wednesday. Morning lows will climb back into the upper 50s to the
lower 60s into the middle of next week.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 66 86 55 73 60 / 30 5 10 20 40
San Angelo 66 87 57 73 61 / 30 10 10 40 40
Junction 66 85 62 75 62 / 40 20 20 40 50
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
130 PM CDT WED APR 8 2015
.AVIATION...
MVFR CIGS WILL GIVE WAY TO VFR CONDITIONS AT SAT/SSF/AUS OVER THE
NEXT 2-4 HOURS AS A SHOWER ACTIVITY DUE TO A WEAK DISTURBANCE
REMAINS TO THE WEST. DRT CIGS WILL REMAIN BORDERLINE IFR/MVFR FOR
A FEW HOURS BEFORE IMPROVING TO BORDERLINE MVFR/VFR WITH SHOWERS
MOST LIKELY BETWEEN 22-02Z. TSTMS CANNOT BE RULED OUT AT DRT
DURING THIS TIME AS HRRR SUGGESTS...BUT ARE UNLIKELY IF LOW CLOUDS
AND SHOWERS CONTINUE UPSTREAM WITHOUT SUFFICIENT CLEARING. EXPECT
CIGS TO LOWER AT ALL SITES TO MVFR BY LATE EVENING AND IFR FOR A
FEW HOURS BETWEEN 09-15Z BEFORE IMPROVING TO MVFR.
LH
&&
.PREV DISCUSSION... /ISSUED 1000 AM CDT WED APR 8 2015/
UPDATE...HAVE INCREASED POPS 10-20% ACROSS THE WESTERN COUNTIES AND
SEGMENTED THE MORNING TIME PERIOD INTO THREE HOUR BLOCKS TO BETTER
ACCOUNT FOR SHOWER TIMING AND PROGRESSION NORTHEASTWARD. HAVE
LOWERED TEMPERATURES OUT WEST GIVEN ADDITIONAL SHOWER COVERAGE
AND ASSOCIATED CLOUD COVER. THIS TREND MAY NEED TO BE REVISITED IF
HRRR OUTPUT IS AN ACCURATE INDICATION OF SHOWER EVOLUTION TODAY.
UPDATES ARE OUT AND UPDATED DISCUSSION CAN BE FOUND BELOW. /ALLEN/
DISCUSSION...ISENTROPIC LIFT IN COMBINATION WITH A MID- TO UPPER-
LEVEL DIVERGENCE DUE TO INCREASING WIND SPEEDS ROUNDING THE BASE OF
A CLOSED H5 LOW OVER NEVADA IS AIDING ELEVATED SHOWER AND
THUNDERSTORM DEVELOPMENT ALONG THE RIO GRANDE. THE 12Z KDRT SOUNDING
REVEALED MUCAPE VALUES NEAR 1000-1500 J/KG WITH THE LFC LOCATED NEAR
10 KFT. THIS HEIGHT IS CO-LOCATED WITH MOISTURE LADEN ISENTROPIC
UPGLIDE WITHIN THIS LAYER AND THUS SUPPORTING SOME THUNDERSTORM
ACTIVITY. THE RAP/HRRR ARE THE MORE AGGRESSIVE SHORT TERM MODELS BUT
SO FAR HAVE BEEN MORE CORRECT OVER PAST COUPLE HOURS. HAVE TRENDED
THE NEXT 3-12 HOURS THIS DIRECTION AND BUMPED UP POPS ALONG AND WEST
OF I-35...ESPECIALLY FOR WESTERN REGIONS AND THE SOUTHERN EDWARDS
PLATEAU. A STRONG STORM OR TWO MAY BE POSSIBLE OUT WEST THIS
AFTERNOON AND TRENDS WILL NEED MONITORED CLOSELY IF ANOTHER POSSIBLE
SHORTWAVE EMBEDDED WITHIN THE INCREASING MID LEVEL FLOW SUPPORTS
GREATER COVERAGE LIKE THE HRRR SUGGESTS. SPC SSEO GIVES CONFIDENCE
THAT THE WEST IS THE FAVORED REGION FOR STRONGER ACTIVITY BUT THE
AMOUNT OF OVERALL PRECIPITATION COVERAGE IS STILL A QUESTION. NOT
READY TO FULLY LEAN TOWARDS THE AGGRESSIVE HRRR DIRECTION ON THIS
UPDATE BUT WILL MONITOR FOR FUTURE UPDATES. /ALLEN/
PREV DISCUSSION... /ISSUED 651 AM CDT WED APR 8 2015/
AVIATION...
MVFR CIGS SHOULD SCATTER OUT FIRST AT KAUS...THEN LATER AT
KSAT/KSSF. WINDS WILL BE S-SE AND FAIRLY STEADY AT 10-15 KTS
THROUGH THE FORECAST PERIOD...BUT DID INCLUDE SOME HIGHER GUSTS
FOR MID TO LATE MORNING. THE ARRIVAL OF A SHORTWAVE TROUGH AND
MORE FAVORABLE SURFACE HEATING SHOULD LEAD TO A BETTER CHANCE OF
-TSRA AT KDRT...SO INCLUDED THAT AS A PROB30 FOR LATE THIS
AFTERNOON AND EARLY EVENING. LOOK FOR MOIST GULF FLOW TO RE-
ESTABLISH MVFR...THEN IFR CIGS OVERNIGHT INTO THURSDAY MORNING.
PREV DISCUSSION... /ISSUED 357 AM CDT WED APR 8 2015/
SHORT TERM (TODAY THROUGH THURSDAY)...
SOUTHERLY LOWER LEVEL FLOW WILL MAINTAIN A MOIST AIRMASS TODAY
INTO THURSDAY WITH A PATTERN OF NIGHT AND MORNING STRATUS MIXING
OUT IN THE AFTERNOON. AN UPPER LEVEL JET STREAK WILL MOVE ACROSS
TEXAS TODAY INTO TONIGHT PUSHING THE DRYLINE EAST ACROSS WESTERN
TEXAS. SOME SHOWERS AND THUNDERSTORMS WILL FORM ALONG THE DRYLINE
AND OVER THE SERRIANAS DEL BURRO AND THEN MOVE ACROSS THE EDWARDS
PLATEAU AND HILL COUNTRY TODAY AND TOWARD THE I-35 CORRIDOR
TONIGHT. CAPE VALUES INDICATE SOME STORMS IN THE EDWARDS PLATEAU
MAY BE STRONG TO MARGINALLY SEVERE THIS AFTERNOON INTO EVENING.
AN UPPER LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN MOVES ACROSS
THE NORTHERN PLAINS FORCING THE DRYLINE EAST INTO THE EDWARDS
PLATEAU AND POSSIBLY FAR NORTHERN HILL COUNTRY ON THURSDAY. THE
MOIST AXIS SHIFTS EAST WITH SHOWERS AND THUNDERSTORMS MAINLY
NORTHEAST OF I-10. CAPE VALUES AGAIN INDICATE A POSSIBILITY OF
STRONG TO MARGINALLY SEVERE STORMS ON THURSDAY. HOWEVER...A
CAPPING INVERSION OF WARM MID LEVEL TEMPERATURES MAY INHIBIT
DEVELOPMENT TODAY AND THURSDAY.
LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...
THE UPPER LEVEL TROUGH CONTINUES FURTHER TO THE NORTHEAST ACROSS
THE GREAT LAKES AND THEN PHASES WITH AN UPPER LEVEL TROUGH OVER
SOUTHEASTERN CANADA. THIS FORCES A COLD FRONT INTO SOUTH CENTRAL
TEXAS ON FRIDAY. SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG THE
FRONT WITH CONVECTIVE PARAMETERS INDICATING A POTENTIAL FOR STRONG
TO MARGINALLY SEVERE STORMS. AGAIN...THIS DEPENDS ON THE AMOUNT OF
INSTABILITY AND THE BREAKING OF THE CAPPING INVERSION. THE FRONT
STALLS JUST SOUTH OF SOUTH CENTRAL TEXAS FRIDAY NIGHT AND THEN
DISSIPATES SATURDAY AS AN UPPER LEVEL TROUGH CURRENTLY OVER JUST
SOUTH OF THE GULF OF ALASKA MOVES INTO NORTHWESTERN MEXICO. THIS
TROUGH MOVES ACROSS TEXAS ON MONDAY WHILE FORCING A PACIFIC FRONT
OR A DRYLINE INTO WESTERN PARTS OF SOUTH CENTRAL TEXAS.
HOWEVER...THERE IS SOME UNCERTAINTY ON ITS SPEED SINCE IT HAS NOT
YET BEEN SAMPLED BY THE NORTH AMERICAN UPPER AIR OBSERVATION
NETWORK. WILL MAINTAIN SHOWERS AND THUNDERSTORMS THIS WEEKEND
ENDING FROM WEST TO EAST ON MONDAY AS THE TROUGH MOVES EAST OF OUR
AREA.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 68 85 66 77 64 / 20 30 30 50 50
AUSTIN BERGSTROM INTL AIRPORT 69 83 66 77 64 / 20 30 30 50 50
NEW BRAUNFELS MUNI AIRPORT 68 85 67 79 65 / 20 20 20 50 50
BURNET MUNI AIRPORT 66 84 63 74 62 / 30 30 40 50 50
DEL RIO INTL AIRPORT 67 89 69 83 67 / 30 - 20 50 50
GEORGETOWN MUNI AIRPORT 67 84 64 75 63 / 30 30 40 50 50
HONDO MUNI AIRPORT 68 86 68 80 66 / 30 10 10 50 50
SAN MARCOS MUNI AIRPORT 68 84 66 78 65 / 20 20 20 50 50
LA GRANGE - FAYETTE REGIONAL 71 84 69 80 67 / 10 20 20 50 50
SAN ANTONIO INTL AIRPORT 69 85 69 79 66 / 20 10 20 50 50
STINSON MUNI AIRPORT 69 86 69 80 67 / 20 10 10 50 50
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...00
SYNOPTIC/GRIDS...15
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1242 PM CDT Wed Apr 8 2015
.AVIATION...
/18Z TAFS/
Scattered showers and storms continue near West Central Texas
terminals this afternoon and tonight. Most of this first wave will
exit the are by mid afternoon, leaving VFR conditions for much of
the afternoon and evening. Stronger storms are possible later this
afternoon and evening, but the activity should be more isolated
and the exact timing is still a question. Will include a VCTS at
KABI (Abilene) for this time period, but will hold off on
mentioning any drop in visibility or ceiling for now. MVFR cigs
move back in overnight as low level moisture streams back into the area.
&&
.PREV DISCUSSION... /ISSUED 807 AM CDT WED APR 8 2015/
AVIATION...
/12Z TAFS/
Good flight conditions will prevail at KABI, KSJT, and KBBD through
the next 24 hours. Farther south, ceilings near 1500 feet this
morning will lift to around 4000 feet by late morning. Southwest
wind gusts near 25 kts are likely late this morning and afternoon at
all terminals. These wind gusts will diminish to near 20 kts after
sunset. Showers and thunderstorms may develop this afternoon/evening.
However, confidence in timing/location remain high enough not to
include in the TAFs at this time.
PREV DISCUSSION... /ISSUED 458 AM CDT Wed Apr 8 2015/
SHORT TERM...
(Today and Tonight)
.Severe weather possible this afternoon/evening...
The forecast challenges are plentiful through the next 24 hours. The
TTU WRF and HRRR models indicate showers should be developing to our
southwest at 4 AM, moving into the region from west to east this
morning through mid-afternoon. They then try to re-develop
convection to our west by late afternoon, with this convection
dissipating before midnight as it approaches our western counties.
Conversely, the NAM/GFS/ECMWF all show nothing for this morning
through mid afternoon, and then develop convection from mid-
afternoon through midnight at varying locations/intensities across
the region. Given the current satellite imagery and upstream
observations, we`ll lean more towards this scenario.
The NAM/GFS have also trended significantly farther west with the
dryline position this afternoon. The ECMWF brings it farther east
with it positioned along a line from eastern Haskell County, to San
Angelo, to west of Ozona. We`ll take a middle-ground approach with
the expectation of the dryline halting its eastward progression,
being located along the western edge of the forecast area. A
strong cap will remain in place for much of the day. By late
afternoon/early evening, a mid-level jet streak will approach the
area from the southwest. Increasing ascent from this, afternoon
mixing, and convergence along the dryline, may be sufficient to
weaken the cap enough for a few storms to develop.
If this occurs, the environment will be characterized by 1500-2500
J/kg of SBCAPE (possibly more if skies are less cloudy than
currently forecast), steep mid-level lapse rates near 8 C/km, with
0-6km effective shear values of 40-55 kts. With this type of setup,
storms would rapidly become severe/supercells with large hail and
damaging winds the main concerns. Soundings also show low-level
winds backing to the southeast, which really increases 0-3km
helicity values making isolated tornadoes a possibility as well,
especially across the northwestern this of the area which is closer
to the track of the mid-level disturbance.
LONG TERM...
(Thursday through Tuesday)
Rain chances remain in most periods of the long term. Another cold
front will push across West Central Texas on Thursday and bring
cooler air, and it will enhance the rain potential for Friday
through the weekend. A developing upper-level disturbance well to
our west will also enhance the rain potential by creating
southwest flow aloft, where embedded minor disturbance will move
across Texas. Isentropic upglide will be best across our southern
counties from Friday through the weekend. Thus, the best chance
for rain will be there. The ECMWF is more aggressive than the GFS
regarding QPF amounts for Friday through the weekend, and the
ECMWF indicates better divergence aloft over Texas for those
periods. So, continuing the best rain chances across our southern
counties looks best. Plus, continuing a PoP forecast closer to
the ECMWF looks better than something closer to the drier GFS.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 84 65 86 55 73 / 50 40 5 10 30
San Angelo 84 65 86 57 73 / 40 40 10 10 30
Junction 83 64 87 62 75 / 40 30 30 10 40
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07