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: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO 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. && $$ 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 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. && $$ 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 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: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
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: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO 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: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
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: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
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: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
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 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 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: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
  [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: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
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 VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
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 FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
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) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
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