Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/26/16
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1206 AM MDT THU MAR 24 2016
.UPDATE...
ISSUED AT 754 PM MDT WED MAR 23 2016
STRONG LOW WILL CONTINUE TO LIFT NORTHEAST OVER THE CENTRAL PLAINS
AND AWAY FROM COLORADO. SNOW AND WINDS WILL CONTINUE TO RAPIDLY
DECREASE THE REST OF THE EVENING ACROSS NORTHEAST COLORADO. EXPECT
SNOW TO END LATE THIS EVENING IN THE FAR NORTHEAST CORNER OF THE
STATE. LOOKS THERE WILL BE ENOUGH MOISTURE EMBEDDED IN THE
NORTHWEST FLOW BEHIND THE EXITING SYSTEM FOR SNOW SHOWERS OVER THE
MOUNTAINS TONIGHT AND THURSDAY. INCREASED POPS SOME FOR THIS.
ACCUMULATIONS WILL BE LIGHT...LESS THAN 2 INCHES.
LET ALL THE ADVISORIES AND WARNINGS EXPIRE EXCEPT FOR THE PLAINS
EAST OF A LINE FROM LIMON TO STERLING. THESE WARNING OVER FAR
EASTERN COLORADO ARE SET TO EXPIRE AT 10 PM. AS WINDS AND SNOW
DECREASE...CONDITIONS WILL CONTINUE TO IMPROVE THIS EVENING AND
PLAN ON EXPIRING THIS BLIZZARD WARNING AT 10 PM.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 243 PM MDT WED MAR 23 2016
VERTICALLY STACKED LOW NOW OVER NORTHWEST KANSAS WILL CONTINUE TO
MOVE EAST OF THE REGION. STRONG FORCING ON THE BACKSIDE OF THE LOW
WILL CONTINUE TO BRING HEAVY SNOW AND STRONG WINDS THE NORTHEAST
PLAINS THROUGH AROUND MID EVENING. ALONG THE FRONT RANGE...WINDS
ARE STARTING TO TURN WESTERLY IN AND NEAR THE FOOTHILLS AND SNOW
HAS STARTED TO DECREASE. EXPECT SNOW TO CONTINUE TO DECREASE AND
END LATE THIS AFTERNOON OR EARLY EVENING ALONG THE FRONT RANGE.
EXTENDED THE WARNINGS OVER THE PLAINS WHERE IT APPEARS SNOW AND
WINDS WILL CONTINUE INTO THE EVENING HOURS.
SNOW IS EXPECTED TO END ACROSS THE AREA BY MIDNIGHT...EXCEPT FOR A
FEW SNOW SHOWERS IN THE MOUNTAINS. COOLED TEMPERATURES FOR
THURSDAY DUE TO THE EXTENSIVE SNOW COVER. SNOW SHOWERS WILL
REMAIN POSSIBLE IN THE MOUNTAINS THURSDAY. ANY NEW SNOWFALL IS
EXPECTED TO BE LIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 319 AM MDT WED MAR 23 2016
DUE TO WEATHER AND COMPUTER ISSUES...VERY LITTLE TO NO CHANGES
WERE MADE. HERE IS THE PREVIOUS DISCUSSION FROM EARLIER THIS
MORNING.
A DISTURBANCE IN THE NW FLOW WILL PUSH IN FRIDAY TO INCREASE SNOW
FOR THE MOUNTAINS BY MORNING...THEN BRING A CHANCE FOR RAIN
SHOWERS OVER THE PLAINS IN THE AFTERNOON. TEMPERATURES SHOULD
WARM FURTHER ON FRIDAY BEFORE THE EXPECTED COLD FRONT PUSHES DOWN
THAT EVENING WITH UPSLOPE CONDITIONS EXPECTED OVER THE PLAINS.
LOOK FOR SNOW TO SPREAD ACROSS THE PLAINS WITH ACCUMULATING SNOW
EXPECTED THROUGH SATURDAY MORNING. THE SYSTEM ALOFT WILL LIKELY BE
AN OPEN WAVE...THOUGH LATEST GFS RUN SLOWS THE KEEPS IT DEEPER...
WITH MODERATE QG LIFT. AMOUNTS ARE HARD TO PINPOINT DOWN AT THIS
POINT...HOWEVER IT WILL BE LESS THAN WHAT IS EXPERIENCED TODAY.
LOCATIONS FAVORED IN UPSLOPE PATTERNS WILL SEE THE HIGHEST TOTALS.
SATURDAYS TEMPERATURES WILL AGAIN BE BACK INTO THE 30S TO LOW 40S
AT BEST.
UPPER RIDGING WILL THEN PUSH INTO THE AREA SUNDAY THEN
SOUTHWESTERLY FLOW ALOFT IS EXPECTED MONDAY AND TUESDAY AHEAD OF
THEN NEXT SYSTEM. LOOK FOR WARMER AND DRIER WEATHER FOR THESE
THREE DAYS...EXCEPT FOR A INCREASING MOISTURE PUSHING IN TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1206 AM MDT THU MAR 24 2016
CLOUDS HAVE SCATTERED OUT ALLOWING FOR PATCHY...DENSE AT TIMES...FOG
FORM IN AREAS OVER THE WESTERN SUBURBS AS WELL AS DOWN OVER THE
PALMER DIVIDE. KBJC HAS ALREADY SEEN VIS OF 1/4 MILE...BUT HAS
SINCE IMPROVED. THERE IS A CHANCE FOR THIS FOG TO PUSH INTO KDEN
AND KAPA OVER THE NEXT FEW HOURS...AS THE HRRR SHOWS. HOWEVER THE
RAP AND GFS...STILL KEEP THE BOUNDARY LAYER TOO DRY FOR FOG. WILL
MENTION VCFG AT THIS TIME DUE TO THE DRAINAGE WINDS MIXING THE
DRIER AIR. IT SEEMS AS THOUGH THE CHANCE WILL BE DONE BY 12Z WITH
ONLY HIGH CLOUDS REMAINING. WINDS SHOULD STAY DRAINAGE/SOUTHERLY
THROUGH THURSDAY NIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MEIER
SHORT TERM...MEIER
LONG TERM...KRIEDERMAN
AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1143 AM EDT THU MAR 24 2016
.SYNOPSIS...
A STATIONARY FRONT WILL REMAIN SOUTH OF LONG ISLAND TODAY AND
THEN MOVE NORTHWARD AS A WARM FRONT TONIGHT. IT MOVES NORTH OF THE
REGION LATE TONIGHT. A COLD FRONT WILL FOLLOW FRIDAY AFTERNOON AND
EVENING. HIGH PRESSURE FROM THE OHIO VALLEY BUILDS IN THEREAFTER
THROUGH THE WEEKEND. LOW PRESSURE MAY IMPACT THE AREA EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST CHALLENGE FOR THE DAY WILL BE THE DEVELOPMENT AND EXTENT
OF STRATUS NORTH OF A STATIONARY FRONT LOCATED ACROSS CENTRAL NJ.
LATEST SAT IMAGERY/OBS SHOW STRATUS EXPANDING ACROSS LI AND
COASTAL CT. DAYTIME HEATING WILL OFFSET SOME OF THE DEVELOPMENT
WITH AREAS FROM NYC AND NORTH AND WEST LIKELY TO SEE MORE SUN.
SOME OF THE HIRES MODELS SUCH AS...RAP...HRRR...AND NARRE HAVE
DIFFERING SOLUTIONS. THE 11Z NARRE HAS DONE FAIRLY WELL WITH THE
COVERAGE AND ACTUALLY BEGINS TO MIX OUT THE STRATUS EVEN ALONG THE
COAST THIS AFTERNOON WITH THE EXCEPTION OF THE TWIN FORKS OF LI.
HOWEVER...THE HRRR EXPANDS THE CLOUD OVER THE ENTIRE FORECAST
AREA THROUGH EARLY AFTERNOON AND THEN STARTS MIXING IT OUT ACROSS
INLAND AREAS. HAVE TAKEN A MIDDLE ROAD APPROACH BASED ON
GRADUALLY INCREASING LOW-LEVEL MOISTURE BENEATH A SHARP LOW-
LEVEL INVERSION....WITH PARTLY SUNNY SKIES FROM NYC NORTH AND
WEST...AND MOSTLY CLOUDY AT THE COAST.
HIGHS COULD ALSO VARY BY SEVERAL DEGREES DEPENDING ON THE AMOUNT
OF CLOUD COVER. FOR THE TIME...HAVE THE UPPER 40S IMMEDIATE
COAST...LOWER 50S TO MID 50S...LI AND CT...AND MID TO UPPER 50S
NYC AND POINTS NORTH AND WEST,
DESPITE THE UPPER LEVEL JET MOVING FARTHER NORTH OF THE REGION
TODAY...WITH RIDGING AT THE MID AND UPPER LEVELS...A MUCH COOLER
ENVIRONMENT WILL BE ENCOMPASSING THE REGION DUE TO A MODIFIED
BOUNDARY LAYER. THE BOUNDARY LAYER WILL HAVE EASTERLY FLOW WITH
LIMITED MIXING HEIGHTS.
A STATIONARY FRONT WILL REMAIN SOUTH OF LONG ISLAND WITH EASTERLY
FLOW DOMINATING. EXPECTING WEATHER TO STAY DRY TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
FOR TONIGHT...WITH THE CONTINUED ENTRAINMENT OF MOISTURE INTO THE
BOUNDARY LAYER AND WITH DRIER AIR ALOFT...THERE WILL BE SOME
POTENTIAL FOR VERY LIGHT RAINFALL OR DRIZZLE THIS EVENING. THIS
WAS HINTED WITHIN SOME MESOSCALE MODELS DEPICTING SOME WEAK
REFLECTIVITY DEVELOPING ACROSS THE REGION.
LATE TONIGHT...THE LOW LEVEL SOUTHWEST JET INCREASES TO 50-60 KT
AT AROUND 900MB. THE FRONT SOUTH OF LONG ISLAND WILL MOVE
NORTHWARD AS A WARM FRONT. THE MIN TEMPERATURES WILL LIKELY BE SET
IN THE EVENING WITH SLIGHTLY RISING TEMPERATURES OVERNIGHT IN
RESPONSE TO INCREASED WARM AIR ADVECTION BEHIND THE WARM FRONT.
THE SOUTHERLY FLOW INCREASES THROUGHOUT THE ATMOSPHERE.
THIS WILL ALLOW FOR RAINFALL TO BECOME MORE INTENSE AND FOR LARGER
RAINDROPS. THE RAIN SHOWERS WILL INCREASE OVERNIGHT INTO FRIDAY.
MUCH OF ANY INSTABILITY IS MOSTLY WEST AND SOUTH OF THE REGION SO
LEFT OUT ANY MENTION OF THUNDERSTORMS. THIS INSTABILITY INCREASES
DURING THE DAY FRIDAY AHEAD OF AN APPROACHING COLD FRONT. THE WARM
AIR ADVECTION WILL BE CONTINUING THROUGH THE DAY. SHOWERS WILL
HAVE SOME EMBEDDED THUNDERSTORMS...BUT WITH MODEL MUCAPE FIELDS IN
DISAGREEMENT WITH ONLY THE NAM SHOWING ANY CAPE ABOVE 100
J/KG...LEFT THE COVERAGE OF THUNDERSTORMS AS ISOLATED.
THE CHANCES FOR SHOWERS DECREASE FRIDAY AFTERNOON FROM WEST TO
EAST. THERE WILL BE SOME TIME WITH THE WINDS SWITCHING TO A MORE
WESTERLY FLOW THAT LATE IN THE DAY...MIXING LENGTHS INCREASE AND
THIS WILL MAKE FOR VERY MILD CONDITIONS. TEMPERATURES ARE FORECAST
TO REBOUND WELL INTO THE 60S AND LOWER 70S FOR A FEW LOCATIONS.
FOR FRIDAY NIGHT...THE ATMOSPHERE CONTINUES TO BECOME DRIER WITH
MORE WESTERLY FLOW. LOW LEVELS WILL HAVE COLD AIR ADVECTION WITH
THE DEVELOPMENT OF MORE NORTHWEST FLOW. HIGH PRESSURE FROM THE
OHIO VALLEY WILL START TO BUILD IN. CLOUDS DECREASE AND WITH A
LIGHTER NORTHWEST FLOW...A LARGE DIURNAL CONTRAST IN TEMPERATURE
WILL BE SET AS LOWS DECREASE TO A RANGE OF UPPER 20S FOR RURAL
INTERIOR LOCATIONS TO 30S FOR MOST LOCATIONS AND LOWER 40S IN NYC.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
DRY CONDITIONS EXPECTED OVER THE WEEKEND AS HIGH PRESSURE BUILDS TO
OUR NORTH. A LOW PRESSURE SYSTEM WILL APPROACH THE AREA SUNDAY
NIGHT...PUSHING A COLD FRONT THROUGH THE AREA ON MONDAY. 00Z ECMWF
AND GFS CONTINUE TO DIFFER ON THE TIMING OF THE FRONT AND DURATION
OF THE PRECIPITATION OF THIS SYSTEM, WITH THE GFS BEING MORE
PROGRESSIVE. AT THIS TIME WILL KEEP PRECIPITATION IN FOR MONDAY.
CANADIAN HIGH BUILDS IN BEHIND THE FRONT AND REMAINS THRU THE MIDDLE
OF NEXT WEEK PRODUCING FAIR AND COOL WEATHER.
TEMPERATURES WILL BE NEAR OR SLIGHTLY ABOVE NORMAL DURING THE LONG
TERM PERIOD WITH HIGH TEMPERATURES IN THE 50S AND LOWS IN THE MID TO
UPPER 30S TO LOW TO MID 40S ACROSS THE NY METRO.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
A FRONTAL BOUNDARY REMAINS SOUTH OF LONG ISLAND TODAY AND THEN
PUSHES NORTH AS WARM FRONT TONIGHT...WITH A COLD FRONT APPROACHING
FRIDAY MORNING.
GUSTY EAST-NORTHEAST WINDS RE-DEVELOP THIS MORNING...WITH 15 TO 20
KT WITH GUSTS TO 25 KT AT KLGA/KBDR. ELSEWHERE 10 TO 15 KT WITH
GUSTS TO 20 KT LIKELY. E/ESE WINDS AND GUSTS SHOULD GRADUALLY WEAKEN
THIS AFTERNOON...THEN SHIFTING S IN WAKE OF WARM FRONT TONIGHT. S
WINDS INCREASE TO 15 TO 20 KT FOR COASTAL TERMINALS LATE TONIGHT.
LLWS LIKELY DEVELOPS TOWARDS MIDNIGHT...AND CONTINUE INTO FRI
MORNING...WITH 50 KT SW FLOW DEVELOPING AT 2KFT.
MVFR STRATUS HAS SHIFTED NORTH...NOW IMPACTING PORTIONS OF THE CITY
TERMINALS AND POINTS EAST. NARRE AND DETERMINISTIC GUIDANCE SUITE
INDICATING STRATUS WILL GRADUALLY LIFT OR SCATTER CIGS TO VFR DURING
THE AFTERNOON...AROUND 17Z-19Z. NOT SURE IF WE EVER BECOME VFR AT
KGON. WE MAY STAY MVFR THROUGH THE DAY.
MVFR STRATUS POTENTIAL SHOULD INCREASE LATE THIS EVENING THROUGH
06Z AHEAD OF WARM FRONT AND THEN POTENTIAL FOR IFR CONDITIONS IN
SHRA LATE TONIGHT AS MOIST AIRMASS MOVES IN WAKE OF WARM FRONT.
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: TIMING OF MVFR STRATUS EROSION COULD BE OFF BY
1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
KLGA FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 25 KT LIKELY INTO EARLY
AFTERNOON.
KEWR FCSTER COMMENTS: GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
KHPN FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY
AFTERNOON.
KISP FCSTER COMMENTS: TIMING OF MVFR STRATUS EROSION COULD BE OFF BY
1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
.OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...
.FRIDAY...IFR OR LOWER CONDS POSSIBLE FRIDAY MORNING WITH -SHRA.
LOW PROB FOR SPARSE THUNDERSTORM COVERAGE. S/SW WINDS 10 TO 15 KT
WITH GUSTS TO 20 KT FRIDAY MORNING. LLWS POTENTIAL THREAT
DECREASING FRI MORNING. CONDS IMPROVING TO MVFR THEN VFR FRI
MORNING INTO AFTERNOON. W-NW WINDS G20-25KT POSSIBLE FRIDAY
AFTERNOON IN WAKE OF COLD FRONT.
.FRIDAY NIGHT...BECOMING VFR. NW-NE WINDS G15-20KT POSSIBLE.
.SATURDAY-SUNDAY...VFR.
.SUNDAY NIGHT-MONDAY...MVFR OR LOWER POSSIBLE IN RAIN AND WIND.
&&
.MARINE...
EASTERLY FLOW WILL INCREASE THE FETCH WITH HIGHER WAVE HEIGHTS IN
THE FORECAST FOR EASTERN LONG ISLAND SOUND AND ACROSS THE OCEAN
ZONES. WIND GUSTS WILL ALSO REACH 25 TO 30 KT ACROSS MOST WATERS
EXCEPT FOR NY HARBOR AND THE SOUTH SHORE BAYS...WHERE THESE WILL
BE JUST OCCASIONAL WITH GUSTS CLOSER TO 20 KT. THEREFORE...SCA
REMAINS IN EFFECT THROUGH THE DAY FOR ALL WATERS EXCEPT FOR NY
HARBOR AND SOUTH SHORE BAYS. HOWEVER...DO EXPECT WIND GUSTS TO
DECREASE SOMEWHAT OVER WESTERN LONG ISLAND SOUND THIS AFTERNOON SO
SCA THERE ONLY GOES TO 18Z. TONIGHT AND FRIDAY...WIND GUSTS WILL
BE MORE LIMITED...SO THE SCA CONDITIONS WILL PREVAIL JUST FOR THE
OCEAN ZONES WHERE HIGHER SEAS WILL BE AND MORE MIXING WILL TAKE
PLACE. FOR FRIDAY NIGHT...THERE COULD BE MORE WIDESPREAD SCA
CONDITIONS WITH COLD AIR ADVECTION OCCURRING BEHIND THE COLD
FRONT.
AS HIGH PRESSURE BUILDS ACROSS THE AREA WATERS ON SATURDAY...SEAS
WILL BEGIN TO FALL BELOW SCA LEVELS BY SATURDAY AFTERNOON. SEAS AND
WINDS STAY BELOW SCA LEVELS THROUGH SUNDAY. LOW PRESSURE WILL IMPACT
THE AREA WATERS ON MONDAY AND INTO TUESDAY..WITH SCA LEVELS WINDS
AND SEAS POSSIBLE.
&&
.HYDROLOGY...
TONIGHT THROUGH FRIDAY...RAIN AMOUNTS WILL RANGE BETWEEN A
QUARTER TO A HALF INCH.
NO SIGNIFICANT WIDESPREAD RAINFALL IS EXPECTED FRIDAY NIGHT AND OVER
THE WEEKEND. ADDITIONAL RAINFALL IS POSSIBLE FOR THE BEGINNING OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ330-
340.
SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR ANZ335.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ350-353-355.
&&
$$
UPDATE...DW
AVIATION...BC
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1116 AM EDT THU MAR 24 2016
.SYNOPSIS...
A STATIONARY FRONT WILL REMAIN SOUTH OF LONG ISLAND TODAY AND
THEN MOVE NORTHWARD AS A WARM FRONT TONIGHT. IT MOVES NORTH OF THE
REGION LATE TONIGHT. A COLD FRONT WILL FOLLOW FRIDAY AFTERNOON AND
EVENING. HIGH PRESSURE FROM THE OHIO VALLEY BUILDS IN THEREAFTER
THROUGH THE WEEKEND. LOW PRESSURE MAY IMPACT THE AREA EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST CHALLENGE FOR THE DAY WILL BE THE DEVELOPMENT AND EXTENT
OF STRATUS NORTH OF A STATIONARY FRONT LOCATED ACROSS CENTRAL NJ.
LATEST SAT IMAGERY/OBS SHOW STRATUS EXPANDING ACROSS LI AND
COASTAL CT. DAYTIME HEATING WILL OFFSET SOME OF THE DEVELOPMENT
WITH AREAS FROM NYC AND NORTH AND WEST LIKELY TO SEE MORE SUN.
SOME OF THE HIRES MODELS SUCH AS...RAP...HRRR...AND NARRE HAVE
DIFFERING SOLUTIONS. THE 11Z NARRE HAS DONE FAIRLY WELL WITH THE
COVERAGE AND ACTUALLY BEGINS TO MIX OUT THE STRATUS EVEN ALONG THE
COAST THIS AFTERNOON WITH THE EXCEPTION OF THE TWIN FORKS OF LI.
HOWEVER...THE HRRR EXPANDS THE CLOUD OVER THE ENTIRE FORECAST
AREA THROUGH EARLY AFTERNOON AND THEN STARTS MIXING IT OUT ACROSS
INLAND AREAS. HAVE TAKEN A MIDDLE ROAD APPROACH BASED ON
GRADUALLY INCREASING LOW-LEVEL MOISTURE BENEATH A SHARP LOW-
LEVEL INVERSION....WITH PARTLY SUNNY SKIES FROM NYC NORTH AND
WEST...AND MOSTLY CLOUDY AT THE COAST.
HIGHS COULD ALSO VARY BY SEVERAL DEGREES DEPENDING ON THE AMOUNT
OF CLOUD COVER. FOR THE TIME...HAVE THE UPPER 40S IMMEDIATE
COAST...LOWER 50S TO MID 50S...LI AND CT...AND MID TO UPPER 50S
NYC AND POINTS NORTH AND WEST,
DESPITE THE UPPER LEVEL JET MOVING FARTHER NORTH OF THE REGION
TODAY...WITH RIDGING AT THE MID AND UPPER LEVELS...A MUCH COOLER
ENVIRONMENT WILL BE ENCOMPASSING THE REGION DUE TO A MODIFIED
BOUNDARY LAYER. THE BOUNDARY LAYER WILL HAVE EASTERLY FLOW WITH
LIMITED MIXING HEIGHTS.
A STATIONARY FRONT WILL REMAIN SOUTH OF LONG ISLAND WITH EASTERLY
FLOW DOMINATING. EXPECTING WEATHER TO STAY DRY TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
FOR TONIGHT...WITH THE CONTINUED ENTRAINMENT OF MOISTURE INTO THE
BOUNDARY LAYER AND WITH DRIER AIR ALOFT...THERE WILL BE SOME
POTENTIAL FOR VERY LIGHT RAINFALL OR DRIZZLE THIS EVENING. THIS
WAS HINTED WITHIN SOME MESOSCALE MODELS DEPICTING SOME WEAK
REFLECTIVITY DEVELOPING ACROSS THE REGION.
LATE TONIGHT...THE LOW LEVEL SOUTHWEST JET INCREASES TO 50-60 KT
AT AROUND 900MB. THE FRONT SOUTH OF LONG ISLAND WILL MOVE
NORTHWARD AS A WARM FRONT. THE MIN TEMPERATURES WILL LIKELY BE SET
IN THE EVENING WITH SLIGHTLY RISING TEMPERATURES OVERNIGHT IN
RESPONSE TO INCREASED WARM AIR ADVECTION BEHIND THE WARM FRONT.
THE SOUTHERLY FLOW INCREASES THROUGHOUT THE ATMOSPHERE.
THIS WILL ALLOW FOR RAINFALL TO BECOME MORE INTENSE AND FOR LARGER
RAINDROPS. THE RAIN SHOWERS WILL INCREASE OVERNIGHT INTO FRIDAY.
MUCH OF ANY INSTABILITY IS MOSTLY WEST AND SOUTH OF THE REGION SO
LEFT OUT ANY MENTION OF THUNDERSTORMS. THIS INSTABILITY INCREASES
DURING THE DAY FRIDAY AHEAD OF AN APPROACHING COLD FRONT. THE WARM
AIR ADVECTION WILL BE CONTINUING THROUGH THE DAY. SHOWERS WILL
HAVE SOME EMBEDDED THUNDERSTORMS...BUT WITH MODEL MUCAPE FIELDS IN
DISAGREEMENT WITH ONLY THE NAM SHOWING ANY CAPE ABOVE 100
J/KG...LEFT THE COVERAGE OF THUNDERSTORMS AS ISOLATED.
THE CHANCES FOR SHOWERS DECREASE FRIDAY AFTERNOON FROM WEST TO
EAST. THERE WILL BE SOME TIME WITH THE WINDS SWITCHING TO A MORE
WESTERLY FLOW THAT LATE IN THE DAY...MIXING LENGTHS INCREASE AND
THIS WILL MAKE FOR VERY MILD CONDITIONS. TEMPERATURES ARE FORECAST
TO REBOUND WELL INTO THE 60S AND LOWER 70S FOR A FEW LOCATIONS.
FOR FRIDAY NIGHT...THE ATMOSPHERE CONTINUES TO BECOME DRIER WITH
MORE WESTERLY FLOW. LOW LEVELS WILL HAVE COLD AIR ADVECTION WITH
THE DEVELOPMENT OF MORE NORTHWEST FLOW. HIGH PRESSURE FROM THE
OHIO VALLEY WILL START TO BUILD IN. CLOUDS DECREASE AND WITH A
LIGHTER NORTHWEST FLOW...A LARGE DIURNAL CONTRAST IN TEMPERATURE
WILL BE SET AS LOWS DECREASE TO A RANGE OF UPPER 20S FOR RURAL
INTERIOR LOCATIONS TO 30S FOR MOST LOCATIONS AND LOWER 40S IN NYC.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
DRY CONDITIONS EXPECTED OVER THE WEEKEND AS HIGH PRESSURE BUILDS TO
OUR NORTH. A LOW PRESSURE SYSTEM WILL APPROACH THE AREA SUNDAY
NIGHT...PUSHING A COLD FRONT THROUGH THE AREA ON MONDAY. 00Z ECMWF
AND GFS CONTINUE TO DIFFER ON THE TIMING OF THE FRONT AND DURATION
OF THE PRECIPITATION OF THIS SYSTEM, WITH THE GFS BEING MORE
PROGRESSIVE. AT THIS TIME WILL KEEP PRECIPITATION IN FOR MONDAY.
CANADIAN HIGH BUILDS IN BEHIND THE FRONT AND REMAINS THRU THE MIDDLE
OF NEXT WEEK PRODUCING FAIR AND COOL WEATHER.
TEMPERATURES WILL BE NEAR OR SLIGHTLY ABOVE NORMAL DURING THE LONG
TERM PERIOD WITH HIGH TEMPERATURES IN THE 50S AND LOWS IN THE MID TO
UPPER 30S TO LOW TO MID 40S ACROSS THE NY METRO.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
A BACK DOOR COLD FRONT REMAINS SOUTH OF LONG ISLAND TODAY AND THEN
PUSHES NORTH AS WARM FRONT TONIGHT...WITH A COLD FRONT APPROACHING
FRIDAY MORNING.
MODERATELY STRONG AND GUSTY ENE WINDS SHOULD RE-DEVELOP THIS
MORNING...WITH 15 TO 20 KT WITH GUSTS TO 25 KT POTENTIAL AT
KLGA/KBDR. ELSEWHERE 10 TO 15 KT WITH GUSTS TO 20 KT LIKELY. E/ESE
WINDS AND GUSTS SHOULD GRADUALLY WEAKEN THIS AFTERNOON...THEN
SHIFTING S IN WAKE OF WARM FRONT TONIGHT. S WINDS INCREASE TO 15
TO 20 KT FOR COASTAL TERMINALS LATE TONIGHT. LLWS LIKELY DEVELOPS
TOWARDS MIDNIGHT...AND CONTINUE INTO FRI MORNING...WITH 50 KT SW
FLOW DEVELOPING AT 2KFT.
IFR STRATUS HAS SHIFTED NORTH...NOW IMPACTING KJFK AND KISP. THIS
STRATUS IS FORECAST TO CONTINUE SPREADING NORTHWARD. NARRE AND
DETERMINISTIC GUIDANCE SUITE INDICATING STRATUS DEVELOPMENT ACROSS
THE CITY/COASTAL TERMINALS THROUGH 14Z...THEN GRADUAL LIFT OR
SCATTERING OF CIGS TO VFR DURING THE AFTERNOON. EXPECTATION IS FOR
IFR STRATUS OFFSHORE TO LIFT TO MVFR THROUGH MID MORNING AS IT
WORKS ONSHORE. SO WILL MAINTAIN FORECAST OF MVFR CIGS DEVELOPING
THROUGH 14-15Z AS MOISTURE TRAPS UNDER INVERSION...AND THEN
SCATTERING OR LIFTING TO VFR IN THE AFTERNOON WITH DAYTIME
HEATING.
MVFR STRATUS POTENTIAL SHOULD INCREASE LATE THIS EVENING THROUGH
06Z AHEAD OF WARM FRONT AND THEN POTENTIAL FOR IFR CONDITIONS IN
SHRA LATE TONIGHT AS MOIST AIRMASS MOVES IN WAKE OF WARM FRONT.
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: TIMING OF MVFR STRATUS EROSION COULD BE OFF BY
1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
KLGA FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 25 KT LIKELY INTO EARLY
AFTERNOON.
KEWR FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY
AFTERNOON.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY
AFTERNOON.
KHPN FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY
AFTERNOON.
KISP FCSTER COMMENTS: TIMING OF MVFR STRATUS EROSION COULD BE OFF BY
1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
.OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...
.FRIDAY...IFR OR LOWER CONDS POSSIBLE FRIDAY MORNING WITH -SHRA.
LOW PROB FOR SPARSE THUNDERSTORM COVERAGE. S/SW WINDS 10 TO 15 KT
WITH GUSTS TO 20 KT FRIDAY MORNING. LLWS POTENTIAL THREAT
DECREASING FRI MORNING. CONDS IMPROVING TO MVFR THEN VFR FRI
MORNING INTO AFTERNOON. W-NW WINDS G20-25KT POSSIBLE FRIDAY
AFTERNOON IN WAKE OF COLD FRONT.
.FRIDAY NIGHT...BECOMING VFR. NW-NE WINDS G15-20KT POSSIBLE.
.SATURDAY-SUNDAY...VFR.
.SUNDAY NIGHT-MONDAY...MVFR OR LOWER POSSIBLE IN RAIN AND WIND.
&&
.MARINE...
EASTERLY FLOW WILL INCREASE THE FETCH WITH HIGHER WAVE HEIGHTS IN
THE FORECAST FOR EASTERN LONG ISLAND SOUND AND ACROSS THE OCEAN
ZONES. WIND GUSTS WILL ALSO REACH 25 TO 30 KT ACROSS MOST WATERS
EXCEPT FOR NY HARBOR AND THE SOUTH SHORE BAYS...WHERE THESE WILL
BE JUST OCCASIONAL WITH GUSTS CLOSER TO 20 KT. THEREFORE...SCA
REMAINS IN EFFECT THROUGH THE DAY FOR ALL WATERS EXCEPT FOR NY
HARBOR AND SOUTH SHORE BAYS. HOWEVER...DO EXPECT WIND GUSTS TO
DECREASE SOMEWHAT OVER WESTERN LONG ISLAND SOUND THIS AFTERNOON SO
SCA THERE ONLY GOES TO 18Z. TONIGHT AND FRIDAY...WIND GUSTS WILL
BE MORE LIMITED...SO THE SCA CONDITIONS WILL PREVAIL JUST FOR THE
OCEAN ZONES WHERE HIGHER SEAS WILL BE AND MORE MIXING WILL TAKE
PLACE. FOR FRIDAY NIGHT...THERE COULD BE MORE WIDESPREAD SCA
CONDITIONS WITH COLD AIR ADVECTION OCCURRING BEHIND THE COLD
FRONT.
AS HIGH PRESSURE BUILDS ACROSS THE AREA WATERS ON SATURDAY...SEAS
WILL BEGIN TO FALL BELOW SCA LEVELS BY SATURDAY AFTERNOON. SEAS AND
WINDS STAY BELOW SCA LEVELS THROUGH SUNDAY. LOW PRESSURE WILL IMPACT
THE AREA WATERS ON MONDAY AND INTO TUESDAY..WITH SCA LEVELS WINDS
AND SEAS POSSIBLE.
&&
.HYDROLOGY...
TONIGHT THROUGH FRIDAY...RAIN AMOUNTS WILL RANGE BETWEEN A
QUARTER TO A HALF INCH.
NO SIGNIFICANT WIDESPREAD RAINFALL IS EXPECTED FRIDAY NIGHT AND OVER
THE WEEKEND. ADDITIONAL RAINFALL IS POSSIBLE FOR THE BEGINNING OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ330-
340.
SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR ANZ335.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ350-353-355.
&&
$$
UPDATE...DW
AVIATION...BC/NV
AREA FORECAST DISCUSSION
NWS KEY WEST FL
1005 PM EDT FRI MAR 25 2016
.DISCUSSION...
A FEW ELEVATED ECHOES ARE PRESENT ON KBYX DOPPLER RADAR THIS
EVENING...BUT WELL BEYOND THE NORTHERN BOUNDARIES OF THE KEYS SERVICE
AREA. WINDS ARE GENTLE TO LIGHT FROM THE EAST TO SOUTHEAST. LAYERED
CLOUDS ARE THINNING FROM THE WEST LATE THIS EVENING...AND
TEMPERATURES ARE IN THE UPPER 70S.
THE LATE EVENING LOCAL SOUNDING SHOWS A DECREASE IN MOISTURE IN THE
LOWEST LAYERS ON A LIGHTER SOUTHERLY FLOW ABOVE THE SURFACE. RIDGING
WILL CONTINUE TO BUILD CLOSER TO THE LOCAL AREA OVERNIGHT AND THERE
IS A LOWERING INVERSION JUST ABOVE H8. ALTHOUGH THE HRRR IS SHOWING A
SLIVER OF SHOWERS LATE TONIGHT JUST TO THE WEST OF THE ISLAND
CHAIN...KEPT THE MENTION OF MEASURABLE PRECIPITATION OUT OF THE
FORECAST TONIGHT. A RECENTLY UPDATED ZONE FORECAST ADJUSTED THE CLOUD
COVER DOWNWARD THROUGH THE OVERNIGHT PERIOD. THE OTHER SENSIBLE
WEATHER ELEMENTS WERE UNCHANGED.
&&
.MARINE...
WINDS WILL HAVE A MINOR ADJUSTMENT IN DIRECTION TO THE EAST/SOUTHEAST
INITIALLY. WILL ALSO REMOVE THE MENTION OF SHOWERS EVERYWHERE EXCEPT
THE STRAITS TONIGHT. NO CAUTIONARY OR ADVISORY CONDITIONS FOR SMALL
CRAFT ARE EXPECTED THROUGH THE WEEKEND IN ANY WATERS SURROUNDING THE
FLORIDA KEYS.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL AT BOTH THE KEY WEST AND MARATHON
TERMINALS THROUGH SATURDAY MORNING. SURFACE WINDS WILL BE MAINLY
FROM THE EAST TO SOUTHEAST NEAR 5 KNOTS.
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE.........04
AVIATION/NOWCASTS.....DEVANAS
DATA COLLECTION.......VICKERY
VISIT US ON THE WEB AT WEATHER.GOV/KEY
FOLLOW US ON FACEBOOK AND TWITTER AT...
WWW.FACEBOOK.COM/NWSKEYWEST
WWW.TWITTER.COM/NWSKEYWEST
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
842 PM EDT FRI MAR 25 2016
.UPDATE (REST OF THE OVERNIGHT)...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOW MUCH OF THE CONUS NOW
UNDER A VERY BROAD LONGWAVE TROUGH. THE FLORIDA PENINSULA RESIDES
WITHIN THE EASTERN BASE REGION OF THIS TROUGH...ALLOWING A SERIES
OF UPPER LEVEL IMPULSES TO QUICKLY MIGRATE ACROSS THE GULF OF
MEXICO AND OVER THE STATE. ONE SUCH IMPULSE BROUGHT QUITE A BIT OF
THUNDERSTORM ACTIVITY TO THE I-4 CORRIDOR OF THE STATE THIS PAST
AFTERNOON...BUT NOW APPEARS TO BE EXITING OFF THE FLORIDA EAST
COAST ALLOWING FOR A QUIETER PERIOD OF WEATHER FOR THE REMAINDER
OF THE EVENING ACROSS OUR FORECAST AREA. HOWEVER...LOOKING AT WV
AND COOLING CLOUD TOPS ACROSS THE EAST-CENTRAL GULF SUGGEST YET
ANOTHER WEAK IMPULSE IS DOWNSTREAM AND HEADED OUR WAY. NUMERICAL
WEATHER PREDICTION HAS HAD A HARD TIME GETTING A GOOD HANDLE ON
THESE WEAK IMPULSES OVER THE GULF...AND HAS NOT BEEN MUCH USE THE
PAST 24 HOURS...EVEN IN THE SHORT TERM. MOST GUIDANCE SOLUTIONS
SUGGEST BETTER RAIN CHANCES WILL BE OVER THE NATURE COAST LATER
TONIGHT...BUT WATCHING THE EXPANDING AREA OF COOLER CLOUD TOPS
TELL US THAT DECENT SYNOPTIC LIFT IS OCCURRING ON A TRAJECTORY
THAT WOULD BRING RAINFALL A BIT FURTHER SOUTH. ALL THIS IS
ASSUMING THE ACTIVITY HOLD TOGETHER ALL THE WAY TO THE COAST. WITH
A LOWER THAN NORMAL CONFIDENCE LEVEL AS TO JUST WHERE AND JUST
WHEN THE NEXT ROUND OF CONVECTION WILL FIND ITS WAY TO THE FLORIDA
PENINSULA...HAVE NOT GONE WITH ANY REALLY HIGH RAIN CHANCES FOR
THE OVERNIGHT...BUT RATHER HAVE SIDED WITH A LOWER AND MORE BROAD
CHANCE POP FOR THE AREA. AS SATELLITE AND RADAR TREND CONTINUE TO
DEVELOP AND CONFIDENCE INCREASES...THESE FORECASTS CAN BE UPDATED
WITH MORE DETAIL...AND HOPEFULLY GIVE A FEW HOURS NOTICE WITH ANY
SIGNIFICANT CHANCES. ALSO HOPEFULLY THE 00Z SUITE OF GUIDANCE WILL
SEE AN IMPROVEMENT IN THE INITIALIZATION OF FEATURES.
SO AS MENTIONED ABOVE...THE NEXT FEW HOURS LOOK GENERALLY
DRY...OTHER THAN A FEW LIGHT SPRINKLES HERE AND THERE. THEN AFTER
MIDNIGHT...RAIN CHANCES INCREASE...ESPECIALLY TOWARD THE COAST AND
FROM TAMPA BAY NORTHWARD AS THE NEXT IMPULSE APPROACHES FROM THE
EASTERN GULF OF MEXICO.
&&
.PREVIOUS DISCUSSION (SATURDAY)...
FOR SATURDAY...THINGS LOOK QUITE SIMILAR...WITH ANOTHER WEAK MID
LEVEL IMPULSE MOVING NORTHEASTWARD ALONG THE STALLED FRONT. THIS
CURRENTLY LOOKS TO FAVOR RAIN ALONG THE NATURE COAST AND INTO THE
NORTHERN FLORIDA PENINSULA...HOWEVER...MUCH LIKE TODAY...IF
CONVECTION DEVELOPS FURTHER SOUTH OVER THE WARM GULF WATERS...THIS
AREA COULD SHIFT SOUTHWARD. MORE SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY LOOKS TO OCCUR DURING THE AFTERNOON HOURS AS THE
SEABREEZE DEVELOPS...WITH THE GREATER RAIN CHANCES OVER INTERIOR
PORTIONS OF THE PENINSULA.
TEMPERATURES WILL GENERALLY REMAIN AT OR ABOVE NORMAL...DEPENDING
LARGELY ON THE EXTENT OF CLOUD COVER AND ANY CONVECTIVE DEBRIS
ADRIFT DURING PEAK HEATING EACH DAY. OVERNIGHT LOWS LOOK TO REMAIN
SOLIDLY IN UPPER 60S TO LOWER 70S TERRITORY.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA
AND SHOULD CONTINUE FOR THE REMAINDER OF THE EVENING. AFTER
MIDNIGHT...THE POTENTIAL WILL EXIST AGAIN FOR MORE SHOWERS AND
POTENTIAL STORMS TO MOVE OFF THE GULF FOR KSRQ/KPIE/KTPA...
HOWEVER...CONFIDENCE IN COVERAGE AND TIMING OF THIS ACTIVITY IS
LOWER THAN AVERAGE. HIGHER DETAIL SHOULD BE POSSIBLE WITH THE 06Z
TAF PACKAGE. FURTHER SOUTH TOWARD KPGD AND KFMY/KRSW...PATCHY FOG
WITH A PERIOD OF MVFR VIS AFTER 08Z IS POSSIBLE...BUT NO
SIGNIFICANT RESTRICTIONS ARE CURRENTLY ANTICIPATED.
&&
.MARINE...
SOUTHERLY WINDS WILL CONTINUE TO THE SOUTH OF A STALLED FRONT
OVER THE FLORIDA PANHANDLE AND SOUTHERN GEORGIA. ANOTHER ROUND OR
TWO OF SHOWERS AND STORMS MOVING ALONG THIS FRONT WILL BE POSSIBLE
ACROSS THE WATERS INTO THE WEEKEND. THE FRONT LOOKS TO SHIFT
SOUTHWARD LATE MONDAY INTO TUESDAY...WITH A NORTHERLY WIND SHIFT
OVER THE NORTHER WATERS. HOWEVER...WINDS AND SEAS LOOK TO REMAIN
WELL BELOW HEADLINE CRITERIA OVER THE NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 70 82 71 83 / 30 30 30 30
FMY 70 87 70 87 / 30 30 30 30
GIF 69 85 70 87 / 30 60 40 60
SRQ 69 79 69 81 / 30 20 30 20
BKV 68 84 68 85 / 30 40 40 50
SPG 70 81 71 83 / 30 20 30 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE...MROCZKA
PREVIOUS DISCUSSION...AUSTIN
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
138 PM EDT THU MAR 24 2016
.Aviation...
[Through 18Z Friday] A line of thunderstorms was taking shape to
the west of the area at 1730Z, and stretched from near MOB to the
southwest. At its current pace, it would arrive near DHN and ECP
terminals around 22-23Z, and at ABY and TLH terminals around
00-01Z. These storms could bring LIFR-IFR visibilities and gusty
winds to 30 knots or more. Otherwise, tonight we expect a mixture
of cloud layers with occasional periods of MVFR or IFR CIGS, and a
gradual improvement after sunrise on Friday. Additional showers
are possible overnight and may linger near TLH and VLD into
tomorrow. An additional round of thunderstorms will be possible
tomorrow at TLH and VLD, but confidence was not high enough to
mention TSRA in the TAFs yet.
&&
.Prev Discussion [1029 AM EDT]...
.Near Term [Rest of Today]...
Although the air mass over our forecast area at 13-14Z was fairly
dry with dewpoints in the 50s (other than along the coast), models
continue to indicate the northward advection of higher dewpoints
through the day today. Coupled with the arrival of some steeper
mid-level lapse rates from the west, and at least some mixed
sunshine today, the ingredients are in place for steady
destabilization - particularly across western parts of the area.
Convection-allowing models have been keen on developing some
showers and storms in the western parts of our area late this
afternoon as the atmosphere destabilizes and warm-air advection
gradually ramps up.
There is currently (14Z) a band of convection stretching from near
Tuscaloosa to near New Orleans, and stretching further SW
offshore. This was making steady progress east, and was generally
not depicted well in many models - even those that initialized
less than 12 hours ago. Recent runs of the HRRR have depicted this
band of convection ahead of the (now-decaying) primary MCS along
the Gulf coast, and those HRRR runs push clusters or lines of
thunderstorms into the western parts of our forecast area around
21Z to 22Z. Whether or not this specific scenario pans out remains
to be seen, but most models do show an increase in convection in
either the late afternoon or early evening. We continue to show
limited PoPs prior to 21Z, with a rapid increase in the western
half of our area between 21-00Z. Some severe wording was added in
those areas as well; given the combination of moderate instability
and shear, some of the storms could be severe from late this
afternoon into this evening.
.Short Term [Friday night Through Saturday]...
A stalled frontal boundary will be in place across Northeast
Florida out into the Gulf of Mexico. A disturbance moving through
the southern stream flow will lead to showers and thunderstorms
developing along the front and lifting northward through the day.
Model guidance continues to remain split regarding the intensity
of this system on Saturday. There seems to be reasonably good
consensus that there will be rain in the area - it`s more a
question of how much. The GFS continues to be on the stronger side
with rainfall amounts, with the NAM/Euro lighter. Overall, went
with a north-south PoP gradient with the highest values along and
south of I-10. Extensive cloudiness will keep temperatures during
the afternoon in the mid 70s.
.Long Term [Saturday Night Through Thursday]...
With one wave moving east of the region on Saturday evening, the
frontal zone will remain nearly stationary across the southern
portion of the region. Model guidance shows a second southern
stream advancing across the Central Gulf Sunday morning ahead of a
northern stream trough racing across the Central Plains. This
system should have a good deal more forcing to work with - thus
feel this system Sunday into Monday will present the greatest
heavy rainfall threat. The 24/00z Euro seems to have shifted
toward the GFS with a little greater QPF this cycle. As a result,
have increased PoPs for Sunday into the 70-80 percent range with
noticeably higher QPF.
By Sunday night, the trailing northern stream trough will be
moving across the Tennessee River Valley and should be
sufficiently strong to sweep the frontal zone south of the
forecast area by Monday afternoon. Drier air will begin to arrive
on Tuesday, with a stretch of dry conditions lasting through
Wednesday.
Thursday looks to feature a return to active weather as the next
system nears the region. Still a lot of details to be worked out
at long ranges, but it appears as though Thursday looks wet, with
some potential for another round of heavy rainfall.
Throughout the period, temperatures are expected to be above
climatology, especially with respect to overnight lows early in
the period. Some cooler and drier air will arrive Tue-Wed, but
should only return temperatures to climatology - before warming
again ahead of Thursday`s storm system.
.Marine...
In general, winds at all of our marine observation sites have been
running near or over the available model guidance. Buoy 42039 to
the south of Panama City has been around 20 knots for a few hours
and recently spiked to 23 knot sustained winds. For that reason,
we have issued a Small Craft Advisory to the west of Apalachicola
until 21Z. That may need to be extended, as some models show
another increase in winds closer to 00Z. Some models do also
indicate a lull in winds today, but given the persistence of
strong winds in the western portions of our coastal waters early
this morning, we issued the advisory.
.Fire Weather...
Hazardous fire weather conditions are not expected through at
least early next week.
.Hydrology...
Three separate periods of rainfall over the next few days will
lead to the potential for river flooding by the end of the weekend
and into next week. While there`s still some uncertainty with
respect to the amounts, it looks at this point like the primary
threat will be more river flooding and less urban flooding. The
most at risk areas for flooding would be our western areas, where
recent rains have stream flows at or just above normal.
Total rainfall from the three systems Thursday evening through
Sunday night could be in the 3 to 5 inch range with isolated
heavier totals possible.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 66 77 64 75 65 / 70 70 50 80 40
Panama City 65 72 62 72 66 / 70 60 50 80 50
Dothan 61 74 55 77 62 / 80 50 20 50 60
Albany 64 73 58 75 62 / 80 70 30 60 50
Valdosta 66 77 64 75 64 / 60 70 50 80 40
Cross City 66 79 67 77 65 / 40 60 60 60 30
Apalachicola 67 74 65 72 67 / 60 60 60 70 40
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk until midnight EDT /11 PM CDT/ tonight FOR
Coastal Bay-South Walton.
GA...NONE.
AL...NONE.
GM...Small Craft Advisory until 5 PM EDT this afternoon FOR Coastal
waters from Apalachicola to Destin FL out 20 NM-Waters from
Apalachicola to Destin FL from 20 to 60 NM.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...GODSEY
LONG TERM...GODSEY
AVIATION...LAMERS
MARINE...LAMERS
FIRE WEATHER...MOORE
HYDROLOGY...GODSEY
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1029 AM EDT THU MAR 24 2016
.Near Term [Rest of Today]...
Although the air mass over our forecast area at 13-14Z was fairly
dry with dewpoints in the 50s (other than along the coast), models
continue to indicate the northward advection of higher dewpoints
through the day today. Coupled with the arrival of some steeper
mid-level lapse rates from the west, and at least some mixed
sunshine today, the ingredients are in place for steady
destabilization - particularly across western parts of the area.
Convection-allowing models have been keen on developing some
showers and storms in the western parts of our area late this
afternoon as the atmosphere destabilizes and warm-air advection
gradually ramps up.
There is currently (14Z) a band of convection stretching from near
Tuscaloosa to near New Orleans, and stretching further SW
offshore. This was making steady progress east, and was generally
not depicted well in many models - even those that initialized
less than 12 hours ago. Recent runs of the HRRR have depicted this
band of convection ahead of the (now-decaying) primary MCS along
the Gulf coast, and those HRRR runs push clusters or lines of
thunderstorms into the western parts of our forecast area around
21Z to 22Z. Whether or not this specific scenario pans out remains
to be seen, but most models do show an increase in convection in
either the late afternoon or early evening. We continue to show
limited PoPs prior to 21Z, with a rapid increase in the western
half of our area between 21-00Z. Some severe wording was added in
those areas as well; given the combination of moderate instability
and shear, some of the storms could be severe from late this
afternoon into this evening.
&&
.Marine...
In general, winds at all of our marine observation sites have been
running near or over the available model guidance. Buoy 42039 to
the south of Panama City has been around 20 knots for a few hours
and recently spiked to 23 knot sustained winds. For that reason,
we have issued a Small Craft Advisory to the west of Apalachicola
until 21Z. That may need to be extended, as some models show
another increase in winds closer to 00Z. Some models do also
indicate a lull in winds today, but given the persistence of
strong winds in the western portions of our coastal waters early
this morning, we issued the advisory.
&&
.Prev Discussion [650 AM EDT]...
.Short Term [Friday night Through Saturday]...
A stalled frontal boundary will be in place across Northeast
Florida out into the Gulf of Mexico. A disturbance moving through
the southern stream flow will lead to showers and thunderstorms
developing along the front and lifting northward through the day.
Model guidance continues to remain split regarding the intensity
of this system on Saturday. There seems to be reasonably good
consensus that there will be rain in the area - it`s more a
question of how much. The GFS continues to be on the stronger side
with rainfall amounts, with the NAM/Euro lighter. Overall, went
with a north-south PoP gradient with the highest values along and
south of I-10. Extensive cloudiness will keep temperatures during
the afternoon in the mid 70s.
.Long Term [Saturday Night Through Thursday]...
With one wave moving east of the region on Saturday evening, the
frontal zone will remain nearly stationary across the southern
portion of the region. Model guidance shows a second southern
stream advancing across the Central Gulf Sunday morning ahead of a
northern stream trough racing across the Central Plains. This
system should have a good deal more forcing to work with - thus
feel this system Sunday into Monday will present the greatest
heavy rainfall threat. The 24/00z Euro seems to have shifted
toward the GFS with a little greater QPF this cycle. As a result,
have increased PoPs for Sunday into the 70-80 percent range with
noticeably higher QPF.
By Sunday night, the trailing northern stream trough will be
moving across the Tennessee River Valley and should be
sufficiently strong to sweep the frontal zone south of the
forecast area by Monday afternoon. Drier air will begin to arrive
on Tuesday, with a stretch of dry conditions lasting through
Wednesday.
Thursday looks to feature a return to active weather as the next
system nears the region. Still a lot of details to be worked out
at long ranges, but it appears as though Thursday looks wet, with
some potential for another round of heavy rainfall.
Throughout the period, temperatures are expected to be above
climatology, especially with respect to overnight lows early in
the period. Some cooler and drier air will arrive Tue-Wed, but
should only return temperatures to climatology - before warming
again ahead of Thursday`s storm system.
.Aviation...
[Through 12Z Friday] A cold front will approach the region today and
slow as it moves over us this evening. VFR conditions are expected
until late in the afternoon with increasing cloudiness at MVFR
levels this evening as the front approaches. MVFR-IFR vsbys will
also be possible with storms ahead of the cold front which will
begin to spread from west to east across the area around 21Z. Winds
from the south will be gusty ahead of the front and may be more
variable and even gustier during stronger storms. Winds will then
shift to the northwest behind the front late in the period.
.Fire Weather...
Hazardous fire weather conditions are not expected through at
least early next week.
.Hydrology...
Three separate periods of rainfall over the next few days will
lead to the potential for river flooding by the end of the weekend
and into next week. While there`s still some uncertainty with
respect to the amounts, it looks at this point like the primary
threat will be more river flooding and less urban flooding. The
most at risk areas for flooding would be our western areas, where
recent rains have stream flows at or just above normal.
Total rainfall from the three systems Thursday evening through
Sunday night could be in the 3 to 5 inch range with isolated
heavier totals possible.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 78 66 77 64 75 / 20 70 60 40 60
Panama City 73 65 72 62 72 / 50 70 40 30 60
Dothan 78 61 74 55 77 / 60 80 40 10 40
Albany 80 64 73 58 75 / 30 80 50 10 40
Valdosta 81 66 77 64 75 / 20 60 70 40 60
Cross City 82 66 79 67 77 / 20 40 50 50 60
Apalachicola 74 67 74 65 72 / 30 60 50 50 70
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AL...NONE.
GM...Small Craft Advisory until 5 PM EDT this afternoon FOR Coastal
waters from Apalachicola to Destin FL out 20 NM-Waters from
Apalachicola to Destin FL from 20 to 60 NM.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...GODSEY
LONG TERM...GODSEY
AVIATION...MOORE
MARINE...LAMERS
FIRE WEATHER...MOORE
HYDROLOGY...GODSEY
SEE THE PREVIOUS LONG TERM FORECAST FORECAST DISCUSSION BELOW.
20
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
/ISSUED AT 418 AM EDT THU MAR 24 2016/
WHILE SHORT TERM FROPA SLOWS AND SETTLES NEAR THE FAR SOUTHEAST
PORTION OF THE AREA FRIDAY NIGHT INTO SATURDAY...WE STAY IN SW
FLOW ALOFT AND ONLY A BRIEF PERIOD WITH QUIET CONDITIONS AS SFC
RIDGE RESULTS IN A RATHER WEAK HYBRID CAD WEDGE. STALLED
BOUNDARY/WEDGE FRONT PROGGED TO LIFT NORTHWARD AS A WARM FRONT
LATE SATURDAY INTO SUNDAY AS GULF MOISTURE OVERRUNNING AND
ISENTROPIC FORCING BRINGS WIDESPREAD SHOWER CHANCES AND TREND OF
THUNDER CHANCES NORTHWARD. MODELS NOW IN BETTER CONSENSUS WITH
FCST EVOLUTION OF DEVELOPING LOW TO TRACK ACROSS THE TN VALLEY
SUNDAY NIGHT THEN PUSH THE ASSOCIATED COLD FRONT SOUTHEASTWARD FOR
MONDAY. AS WITH THE LAST SEVERAL SYSTEMS...WILL NEED TO WATCH FOR
UPSTREAM GULF CONVECTION POTENTIALLY ROBBING US OF MOISTURE
TRANSPORT BUT FOR NOW LOOKS LIKE A GOOD BET FOR LIKELY POPS IN THE
SUNDAY TO SUNDAY NIGHT TIME FRAME. BEST CHANCE FOR THUNDER LOOKS
TO BE SUNDAY AFTERNOON GIVEN FCST CAPE...THOUGH BETTER SHEAR
ENVIRONMENT LOOKS TO BE WITH FROPA LATE SUNDAY NIGHT INTO MONDAY.
DIFFICULT TO SAY WHICH TIME WOULD BE MORE SUPPORTIVE OF STRONGER
CONVECTION AT THE MOMENT SO WILL KEEP MONITORING OF TRENDS.
OTHERWISE THIS SECOND SYSTEM IS FOLLOWED BY A STRONGER RIDGE SO NO
WORRIES OF A LINGERING BOUNDARY TO THE SOUTH FOR TUES/WED AND
SHOULD BE DRY AND PLEASANT. ACTIVE LONGWAVE PATTERN CONTINUES
THOUGH FOR END OF FCST PERIOD WITH MOISTURE ADVECTION AHEAD OF THE NEXT
FRONTAL SYSTEM STARTING TO INFLUENCE THE AREA WED NIGHT INTO
THURS...STARTED CHANCE POPS TREND ACCORDINGLY.
DESPITE THE ACTIVE PERIOD...TEMPS FOR THE MOST PART STAY SLIGHTLY
ABOVE NORMAL THROUGHOUT. SATURDAY IS WARMEST PERIOD WITH HIGHS IN
THE MID 70S ACROSS MAJORITY OF AREA...AND MONDAY NIGHT IS COOLEST
BEHIND AFOREMENTIONED FROPA WITH LOWS IN LOW TO MID 40S BUT STILL
NOT LOW ENOUGH TO RAISE FROST/FREEZE CONCERNS.
BAKER
&&
.AVIATION...
06Z UPDATE...
COLD FRONT STILL RESIDES TO THE NW OF ALL OF THE TAF SITES WITH A
BKN LINE OF LIGHT SHRA ALONG ITS LEADING EDGE. EXPECT THIS TO
SLOWLY APPROACH THROUGH THE EARLY MORNING HOURS BUT IMPACT SHOULD
BE MINIMAL. MAIN ISSUE WILL BE THE LOWER CIG TREND WITH IFR
ANTICIPATED AT ALL SITES BY 08Z WITH EVEN SOME POTENTIAL FOR LIFR
THROUGH THE EARLY MORNING HOURS. VERY SLOW IMPROVEMENT TREND
ANTICIPATED TODAY BUT SHOULD SEE VFR CONDITIONS LATE AS LONG AS
FRONT PROGRESSES AS FORECAST.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON SHRA POTENTIAL.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 74 49 76 53 / 20 10 10 20
ATLANTA 69 50 74 57 / 20 10 10 30
BLAIRSVILLE 66 42 70 47 / 10 10 10 20
CARTERSVILLE 68 42 73 51 / 10 10 5 20
COLUMBUS 73 53 77 60 / 30 30 20 40
GAINESVILLE 70 48 71 53 / 20 10 10 20
MACON 74 53 76 59 / 40 30 20 30
ROME 67 41 73 51 / 10 10 5 20
PEACHTREE CITY 70 45 75 54 / 20 20 10 30
VIDALIA 76 61 75 62 / 50 30 30 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...DEESE
LONG TERM....31
AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
608 PM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE AREA FRIDAY THEN RETURN NORTH
AS A WARM FRONT SUNDAY. ANOTHER COLD FRONT WILL CROSS THE AREA
MONDAY. HIGH PRESSURE WILL OVERSPREAD THE REGION TUESDAY AND
WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
MAIN FORECAST PROBLEM THIS EVENING IS THE APPROACHING LINE OF
CONVECTION FROM THE WEST. IT HAS SHOT WELL AHEAD OF THE COLD
FRONT...AND WILL BE MOVING INTO A MORE STABLE ENVIRONMENT
OVERNIGHT...SO THE THREAT OF SEVERE WEATHER IN THE CWA IS
PRACTICALLY NIL. HRRR MODEL CAUGHT ON TO THIS CONCEPT BY EARLY
AFTERNOON...AND IS THE MODEL OF CHOICE FOR THE NEXT SEVERAL
HOURS.
DESPITE THE LACK OF SURFACE INSTABILITY...WE WILL BE CLOSE ENOUGH
TO THE DIVERGENT PORTION OF THE UPPER LEVEL JET TO HAVE SOME
DECENT SYNOPTIC SCALE LIFT. ADDITIONALLY...A NOTICEABLE MESOSCALE
VORTEX HAS DEVELOPED ON THE NORTHERN END OF THE STRONG CONVECTION
IN SOUTHWEST GEORGIA THIS EVENING...AND ITS REMNANTS MAY APPROACH
THE SOUTHWESTERN PORTION OF THE CWA LATE TONIGHT...PROVIDING SOME
MESOSCALE LIFT. DUE TO THESE TWO FACTORS...I HAVE ADDED ISOLATED
THUNDER OVERNIGHT.
TEMPS WILL BE QUITE MILD FOR MARCH WITH OVERNIGHT LOWS BOTTOMING
OUT IN THE LOWER TO MID 60S. NOT QUITE WARM ENOUGH TO BE A RECORD
HIGH MIN...THOUGH...WHICH IS 67 AT CAE.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL CROSS THE MIDLANDS AND CSRA DURING THE DAY
FRIDAY AND STALL JUST SOUTH AND EAST OF THE AREA FRIDAY NIGHT INTO
SATURDAY. THERE IS SOME UNCERTAINTY AS TO HOW FAR SOUTH THE FRONT
WILL MOVE BEFORE STALLING. THE NAM MODEL STALLS THE FRONT ACROSS
THE CENTRAL MIDLANDS...WHILE THE GFS AND ECMWF ALLOWS THE FRONT TO
SHIFT JUST SOUTH OF THE CSRA. THE HIGHEST INSTABILITY WILL BE
ACROSS THE EASTERN HALF OF THE FORECAST AREA FRIDAY AND
SATURDAY...SO CAN NOT RULE OUT A FEW THUNDERSTORMS DURING THE DAY.
SHOULD SEE SOME DRYING ACROSS THE NORTH AND WESTERN MIDLANDS
BEHIND THE FRONT. WILL INDICATE SLIGHT CHANCE POPS ACROSS THE
NORTH MIDLANDS SATURDAY WITH CHANCE POPS FARTHER SOUTH. SPC DOES
HAVE THE CENTRAL AND EASTERN PORTIONS OF THE CWA IN A MARGINAL
RISK OF STORMS ON FRIDAY. SHOULD SEE TEMPERATURES A FEW DEGREES
ABOVE NORMAL ON FRIDAY AND NEAR NORMAL ON SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
MEDIUM RANGE MODELS SHOW AN UPPER LEVEL TROUGH OVER THE PLAINS ON
SUNDAY MOVING EAST TO CROSS THE EASTERN STATES ON MONDAY. A WARM
FRONT IS FORECAST TO LIFT NORTHWARD ACROSS THE REGION SUNDAY
FOLLOWED BY A COLD FRONT CROSSING THE REGION MONDAY INTO MONDAY
NIGHT. SHOULD SEE A PERIOD OF PRECIP SUNDAY THEN AGAIN WITH THE
COLD FRONT MONDAY.
UPPER LEVEL RIDGE IS FORECAST TO BUILD FROM THE CENTRAL CONUS TO THE
EAST COAST TUESDAY THROUGH WEDNESDAY...MOVING OFF THE OFF THE COAST
THURSDAY. THE ECMWF IS A LITTLE SLOWER AND AMPLIFIED THAN THE GFS
AND GFS ENSEMBLE. SURFACE HIGH PRESSURE WILL BUILD ACROSS THE REGION
TUESDAY AND WEDNESDAY. THE FASTER GFS HAS PRE-FRONTAL CONVECTION
AFFECTING THE AREA THURSDAY WHILE THE SLOWER ECMWF HOLD CONVECTION
TO OUR WEST THROUGH THURSDAY.
TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS EXPECTED THROUGH AT LEAST EARLY TONIGHT. SURFACE HIGH
PRESSURE OFF THE SE COAST WILL SLIP TO THE EAST...AS A COLD FRONT
APPROACHES FROM THE WEST. A CONTINUED S TO SW LOW LEVEL FLOW WILL
CONTINUE. SHOWER ACTIVITY ASSOCIATED WITH THE FRONT IS EXPECTED TO
WEAKEN AND DIMINISH IN COVERAGE AS IT CROSS THE FORECAST AREA (FA)
LATE TONIGHT. WILL HANDLE WITH PREDOMINATE MENTION OF SHOWER WITH
MVFR CIGS/VSBYS. FRONT TO SLOWLY SLIP SOUTH THROUGH THE FA
FRIDAY...WILL INDICATE SOME DIURNAL IMPROVEMENT IN CIGS TO VFR
AND INCLUDE VCSH.
EXTENDED AVIATION OUTLOOK...SOME RAIN CHANCES WITH MAINLY LATE
NIGHT/MORNING MVFR TO POSSIBLY IFR CIGS AT TIMES FRIDAY AND
SATURDAY. BEST CHANCES OF RAIN AND RESTRICTIONS APPEAR TO BE LATE
SATURDAY NIGHT AND SUNDAY. NO IMPACTS TO AVIATION MONDAY AND
TUESDAY...EXCEPT BREEZY CONDITIONS POSSIBLE MONDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
&&
$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
126 PM EDT THU MAR 24 2016
.PREV DISCUSSION... /ISSUED 957 AM EDT THU MAR 24 2016/
UPDATE...
COLD FRONT IS CURRENTLY SITUATED JUST WEST OF THE MISSISSIPPI
RIVER THIS MORNING...WHILE THE SQUALL LINE IS JUST NOW CROSSING
THE RIVER. THE MODELS CONTINUE TO SHIFT THE FILLING LOW PRESSURE
SYSTEM/SHORTWAVE OFF TO THE NORTHEAST.
THERE IS SOME DIFFERENCES BETWEEN THE HI-RES MODELS MODELS THIS
MORNING...WITH THE HRRR A LITTLE FASTER THAN THE REST. THE ARW HAS
BEEN THE MOST CONSISTENT. SCATTERED SHOWERS WILL BE POSSIBLE FOR
THE LATE MORNING/EARLY AFTERNOON IN THE WESTERN PORTION OF THE
CWFA. THE STRONGER ACTIVITY SHOULD BEGIN TO MOVE IN AROUND 18Z.
WITH THE MAIN COLD POOL WELL TO THE NORTH...THE MID LEVEL LAPSE
RATES ARE NOT AS STEEP AS THEY WERE YESTERDAY. HOWEVER...THERE
WILL BE ENOUGH SHEAR AND WITH A 40-50KT LLJ...THE FRONT MAY
PROVIDE ENOUGH LIFT TO PROVIDE ENOUGH POTENTIAL FOR A FEW SEVERE
THUNDERSTORMS LATE THIS AFTERNOON AND EVENING. THE PRIMARY THREATS
SHOULD BE DAMAGING WIND GUSTS AND POSSIBLY SOME LARGE HAIL CLOSEST
TO THE MID LEVEL COLD POOL. AN ISOLATED TORNADO IS STILL
POSSIBLE.
FOR THE UPDATE...HAVE TWEAKED POPS A BIT FOR EARLY THIS MORNING.
THE SHOWERS HAVE BEEN A LITTLE SLOWER TO PROGRESS INTO NW GA.
TEMPS/DEWS LOOKED ALRIGHT SO MADE VERY LITTLE CHANGE.
PREV DISCUSSION... /ISSUED 726 AM EDT THU MAR 24 2016/
PREV DISCUSSION... /ISSUED /
SHORT TERM /TODAY THROUGH FRIDAY/...
LATEST SURFACE ANALYSIS SHOWS HIGH PRESSURE WELL OFF THE CAROLINA
COAST AND THE MAJOR INFLUENCER OF THE SE WEATHER PATTERN. RETURN
FLOW FROM THIS HIGH IS PRODUCING SOUTHERLY FLOW BOTH AT GROUND
LEVEL AND JUST OFF THE SURFACE ALLOWING FOR AN INITIAL 5K FT DECK
OF CLOUDS TO PUSH INTO PORTIONS OF NORTH GA. SOUTHERLY FLOW ALSO
PLAYING A MAJOR ROLE IN KEEPING TEMPERATURES ELEVATED THIS
OVERNIGHT PERIOD WITH VALUES HOLDING IN THE 50S AND EVEN SOME 60S
STILL OUT THERE.
THE MAIN ISSUE AT LEAST INITIALLY WILL BE THE TIMING OF THE PRE-
FRONTAL ACTIVITY AS WELL AS THE STRENGTH OF THAT ACTIVITY. HI RES
MODELS ARE AGREEING A LITTLE BETTER WITH THE LATEST RUNS IN
BRINGING A LINE OF SHRA TO THE AREA BY 20Z. MUCAPE DURING THIS
TIME PERIOD AND PRIOR TO 00Z LOOKS ONLY ON THE ORDER OF 50 TO 100
J/KG AND PREFER TO KEEP THUNDER OUT OF THE FORECAST FOR THIS FIRST
PHASE.
PHASE 2 HOWEVER WHICH IS FROM 00Z TO 06Z LOOKS TO INCLUDE
MORE ROBUST CONVECTION WITH CAPE VALES NEAR 1000 J/KG PUSHING IN
FROM THE SW AND ROUGHLY ALONG AND SOUTH OF THE I85 CORRIDOR. IN
FACT...ALTHOUGH GREATER SHEAR WILL BE TO THE NORTH....IT IS THIS
AFOREMENTIONED ZONE THAT COULD END UP HAVING THE STRONGER STORMS
GIVEN THE BETTER BALANCE OF INSTABILITY AND SHEAR. OVERALL...THESE
SHEAR VALUES FAVOR DAMAGING WIND GUSTS ALTHOUGH LOW LEVEL HELICITY
IS SUFFICIENT FOR ISOLATED TORNADOES AS WELL. THE LARGE HAIL WILL
BE CONFINED TO THE AREAS WITH THE GREATER MID LEVEL INSTABILITY
WHICH SHOULD BE THE SOUTHERN ZONES BASED ON LATEST MODEL DATA.
THE BIGGEST QUESTION FOR THIS FORECAST CYCLE IS ACTUALLY HOW FAR
SOUTH THE FRONT WILL PROGRESS AND THE TIMING OF ANY CLEARING. GFS
AND ECMWF CONTINUE TO BE THE MOST AGGRESSIVE WITH FRONTAL PASSAGE
BRINGING CLEARING CONDITIONS TO THE NORTH GEORGIA REGION LATE
THURSDAY NIGHT INTO FRIDAY MORNING WHILE THE NAM12 HANGS THE FRONT
UP OVER N GA KEEPING POPS IN MUCH LONGER. FOR NOW WILL GO WITH THE
CONSENSUS OF THE MORE PROGRESSIVE MODELS WITH A GOOD CLEARING
TREND DOWN TO MACON THROUGH FRIDAY MORNING.
DEESE
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
WHILE SHORT TERM FROPA SLOWS AND SETTLES NEAR THE FAR SOUTHEAST
PORTION OF THE AREA FRIDAY NIGHT INTO SATURDAY...WE STAY IN SW
FLOW ALOFT AND ONLY A BRIEF PERIOD WITH QUIET CONDITIONS AS SFC
RIDGE RESULTS IN A RATHER WEAK HYBRID CAD WEDGE. STALLED
BOUNDARY/WEDGE FRONT PROGGED TO LIFT NORTHWARD AS A WARM FRONT
LATE SATURDAY INTO SUNDAY AS GULF MOISTURE OVERRUNNING AND
ISENTROPIC FORCING BRINGS WIDESPREAD SHOWER CHANCES AND TREND OF
THUNDER CHANCES NORTHWARD. MODELS NOW IN BETTER CONSENSUS WITH
FCST EVOLUTION OF DEVELOPING LOW TO TRACK ACROSS THE TN VALLEY
SUNDAY NIGHT THEN PUSH THE ASSOCIATED COLD FRONT SOUTHEASTWARD FOR
MONDAY. AS WITH THE LAST SEVERAL SYSTEMS...WILL NEED TO WATCH FOR
UPSTREAM GULF CONVECTION POTENTIALLY ROBBING US OF MOISTURE
TRANSPORT BUT FOR NOW LOOKS LIKE A GOOD BET FOR LIKELY POPS IN THE
SUNDAY TO SUNDAY NIGHT TIME FRAME. BEST CHANCE FOR THUNDER LOOKS
TO BE SUNDAY AFTERNOON GIVEN FCST CAPE...THOUGH BETTER SHEAR
ENVIRONMENT LOOKS TO BE WITH FROPA LATE SUNDAY NIGHT INTO MONDAY.
DIFFICULT TO SAY WHICH TIME WOULD BE MORE SUPPORTIVE OF STRONGER
CONVECTION AT THE MOMENT SO WILL KEEP MONITORING OF TRENDS.
OTHERWISE THIS SECOND SYSTEM IS FOLLOWED BY A STRONGER RIDGE SO NO
WORRIES OF A LINGERING BOUNDARY TO THE SOUTH FOR TUES/WED AND
SHOULD BE DRY AND PLEASANT. ACTIVE LONGWAVE PATTERN CONTINUES
THOUGH FOR END OF FCST PERIOD WITH MOISTURE ADVECTION AHEAD OF THE NEXT
FRONTAL SYSTEM STARTING TO INFLUENCE THE AREA WED NIGHT INTO
THURS...STARTED CHANCE POPS TREND ACCORDINGLY.
DESPITE THE ACTIVE PERIOD...TEMPS FOR THE MOST PART STAY SLIGHTLY
ABOVE NORMAL THROUGHOUT. SATURDAY IS WARMEST PERIOD WITH HIGHS IN
THE MID 70S ACROSS MAJORITY OF AREA...AND MONDAY NIGHT IS COOLEST
BEHIND AFOREMENTIONED FROPA WITH LOWS IN LOW TO MID 40S BUT STILL
NOT LOW ENOUGH TO RAISE FROST/FREEZE CONCERNS.
BAKER
&&
.AVIATION...
18Z UPDATE...
ACTIVE RADAR JUST TO THE WEST. THE LATE AFTERNOON AND EVENING
HOURS WILL BE DOMINATED BY THE LINES OF CONVECTION ASSOCIATED
WITH A FRONTAL PASSAGE. THE HI-RES MODELS HAVE BEEN CONSISTENTWITH
TIMING...WITH THE FIRST LINE COMING THROUGH IN THE EARLY EVENING
AND THE SECOND OVERNIGHT. HOWEVER...AM CONCERNED THAT THIS WILL
ACTUALLY OCCUR WITH THE CURRENT RADAR PRESENTATION. WINDS WILL
REMAIN ON THE WEST SIDE. ALSO...AFTER ANY PRECIP IFR CLOUDS ARE
LIKELY...BREAKING OUT BY MID MORNING TOMORROW.
//ATL CONFIDENCE...18Z UPDATE...
LOW TO MED CONFIDENCE ON CONVECTION. MED CONFIDENCE REMAINING
ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 78 57 73 48 / 70 90 30 10
ATLANTA 76 56 68 49 / 90 100 20 10
BLAIRSVILLE 68 50 65 41 / 90 100 20 10
CARTERSVILLE 72 51 67 41 / 90 100 20 10
COLUMBUS 78 59 73 52 / 70 100 30 30
GAINESVILLE 71 54 69 48 / 80 100 20 10
MACON 80 63 73 51 / 50 80 40 30
ROME 71 49 67 41 / 90 100 10 10
PEACHTREE CITY 76 56 70 44 / 80 100 20 20
VIDALIA 80 66 76 60 / 20 50 50 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...
AVIATION...
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
957 AM EDT THU MAR 24 2016
.UPDATE...
COLD FRONT IS CURRENTLY SITUATED JUST WEST OF THE MISSISSIPPI
RIVER THIS MORNING...WHILE THE SQUALL LINE IS JUST NOW CROSSING
THE RIVER. THE MODELS CONTINUE TO SHIFT THE FILLING LOW PRESSURE
SYSTEM/SHORTWAVE OFF TO THE NORTHEAST.
THERE IS SOME DIFFERENCES BETWEEN THE HI-RES MODELS MODELS THIS
MORNING...WITH THE HRRR A LITTLE FASTER THAN THE REST. THE ARW HAS
BEEN THE MOST CONSISTENT. SCATTERED SHOWERS WILL BE POSSIBLE FOR
THE LATE MORNING/EARLY AFTERNOON IN THE WESTERN PORTION OF THE
CWFA. THE STRONGER ACTIVITY SHOULD BEGIN TO MOVE IN AROUND 18Z.
WITH THE MAIN COLD POOL WELL TO THE NORTH...THE MID LEVEL LAPSE
RATES ARE NOT AS STEEP AS THEY WERE YESTERDAY. HOWEVER...THERE
WILL BE ENOUGH SHEAR AND WITH A 40-50KT LLJ...THE FRONT MAY
PROVIDE ENOUGH LIFT TO PROVIDE ENOUGH POTENTIAL FOR A FEW SEVERE
THUNDERSTORMS LATE THIS AFTERNOON AND EVENING. THE PRIMARY THREATS
SHOULD BE DAMAGING WIND GUSTS AND POSSIBLY SOME LARGE HAIL CLOSEST
TO THE MID LEVEL COLD POOL. AN ISOLATED TORNADO IS STILL
POSSIBLE.
FOR THE UPDATE...HAVE TWEAKED POPS A BIT FOR EARLY THIS MORNING.
THE SHOWERS HAVE BEEN A LITTLE SLOWER TO PROGRESS INTO NW GA.
TEMPS/DEWS LOOKED ALRIGHT SO MADE VERY LITTLE CHANGE.
&&
.PREV DISCUSSION... /ISSUED 726 AM EDT THU MAR 24 2016/
PREV DISCUSSION... /ISSUED /
SHORT TERM /TODAY THROUGH FRIDAY/...
LATEST SURFACE ANALYSIS SHOWS HIGH PRESSURE WELL OFF THE CAROLINA
COAST AND THE MAJOR INFLUENCER OF THE SE WEATHER PATTERN. RETURN
FLOW FROM THIS HIGH IS PRODUCING SOUTHERLY FLOW BOTH AT GROUND
LEVEL AND JUST OFF THE SURFACE ALLOWING FOR AN INITIAL 5K FT DECK
OF CLOUDS TO PUSH INTO PORTIONS OF NORTH GA. SOUTHERLY FLOW ALSO
PLAYING A MAJOR ROLE IN KEEPING TEMPERATURES ELEVATED THIS
OVERNIGHT PERIOD WITH VALUES HOLDING IN THE 50S AND EVEN SOME 60S
STILL OUT THERE.
THE MAIN ISSUE AT LEAST INITIALLY WILL BE THE TIMING OF THE PRE-
FRONTAL ACTIVITY AS WELL AS THE STRENGTH OF THAT ACTIVITY. HI RES
MODELS ARE AGREEING A LITTLE BETTER WITH THE LATEST RUNS IN
BRINGING A LINE OF SHRA TO THE AREA BY 20Z. MUCAPE DURING THIS
TIME PERIOD AND PRIOR TO 00Z LOOKS ONLY ON THE ORDER OF 50 TO 100
J/KG AND PREFER TO KEEP THUNDER OUT OF THE FORECAST FOR THIS FIRST
PHASE.
PHASE 2 HOWEVER WHICH IS FROM 00Z TO 06Z LOOKS TO INCLUDE
MORE ROBUST CONVECTION WITH CAPE VALES NEAR 1000 J/KG PUSHING IN
FROM THE SW AND ROUGHLY ALONG AND SOUTH OF THE I85 CORRIDOR. IN
FACT...ALTHOUGH GREATER SHEAR WILL BE TO THE NORTH....IT IS THIS
AFOREMENTIONED ZONE THAT COULD END UP HAVING THE STRONGER STORMS
GIVEN THE BETTER BALANCE OF INSTABILITY AND SHEAR. OVERALL...THESE
SHEAR VALUES FAVOR DAMAGING WIND GUSTS ALTHOUGH LOW LEVEL HELICITY
IS SUFFICIENT FOR ISOLATED TORNADOES AS WELL. THE LARGE HAIL WILL
BE CONFINED TO THE AREAS WITH THE GREATER MID LEVEL INSTABILITY
WHICH SHOULD BE THE SOUTHERN ZONES BASED ON LATEST MODEL DATA.
THE BIGGEST QUESTION FOR THIS FORECAST CYCLE IS ACTUALLY HOW FAR
SOUTH THE FRONT WILL PROGRESS AND THE TIMING OF ANY CLEARING. GFS
AND ECMWF CONTINUE TO BE THE MOST AGGRESSIVE WITH FRONTAL PASSAGE
BRINGING CLEARING CONDITIONS TO THE NORTH GEORGIA REGION LATE
THURSDAY NIGHT INTO FRIDAY MORNING WHILE THE NAM12 HANGS THE FRONT
UP OVER N GA KEEPING POPS IN MUCH LONGER. FOR NOW WILL GO WITH THE
CONSENSUS OF THE MORE PROGRESSIVE MODELS WITH A GOOD CLEARING
TREND DOWN TO MACON THROUGH FRIDAY MORNING.
DEESE
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
WHILE SHORT TERM FROPA SLOWS AND SETTLES NEAR THE FAR SOUTHEAST
PORTION OF THE AREA FRIDAY NIGHT INTO SATURDAY...WE STAY IN SW
FLOW ALOFT AND ONLY A BRIEF PERIOD WITH QUIET CONDITIONS AS SFC
RIDGE RESULTS IN A RATHER WEAK HYBRID CAD WEDGE. STALLED
BOUNDARY/WEDGE FRONT PROGGED TO LIFT NORTHWARD AS A WARM FRONT
LATE SATURDAY INTO SUNDAY AS GULF MOISTURE OVERRUNNING AND
ISENTROPIC FORCING BRINGS WIDESPREAD SHOWER CHANCES AND TREND OF
THUNDER CHANCES NORTHWARD. MODELS NOW IN BETTER CONSENSUS WITH
FCST EVOLUTION OF DEVELOPING LOW TO TRACK ACROSS THE TN VALLEY
SUNDAY NIGHT THEN PUSH THE ASSOCIATED COLD FRONT SOUTHEASTWARD FOR
MONDAY. AS WITH THE LAST SEVERAL SYSTEMS...WILL NEED TO WATCH FOR
UPSTREAM GULF CONVECTION POTENTIALLY ROBBING US OF MOISTURE
TRANSPORT BUT FOR NOW LOOKS LIKE A GOOD BET FOR LIKELY POPS IN THE
SUNDAY TO SUNDAY NIGHT TIME FRAME. BEST CHANCE FOR THUNDER LOOKS
TO BE SUNDAY AFTERNOON GIVEN FCST CAPE...THOUGH BETTER SHEAR
ENVIRONMENT LOOKS TO BE WITH FROPA LATE SUNDAY NIGHT INTO MONDAY.
DIFFICULT TO SAY WHICH TIME WOULD BE MORE SUPPORTIVE OF STRONGER
CONVECTION AT THE MOMENT SO WILL KEEP MONITORING OF TRENDS.
OTHERWISE THIS SECOND SYSTEM IS FOLLOWED BY A STRONGER RIDGE SO NO
WORRIES OF A LINGERING BOUNDARY TO THE SOUTH FOR TUES/WED AND
SHOULD BE DRY AND PLEASANT. ACTIVE LONGWAVE PATTERN CONTINUES
THOUGH FOR END OF FCST PERIOD WITH MOISTURE ADVECTION AHEAD OF THE NEXT
FRONTAL SYSTEM STARTING TO INFLUENCE THE AREA WED NIGHT INTO
THURS...STARTED CHANCE POPS TREND ACCORDINGLY.
DESPITE THE ACTIVE PERIOD...TEMPS FOR THE MOST PART STAY SLIGHTLY
ABOVE NORMAL THROUGHOUT. SATURDAY IS WARMEST PERIOD WITH HIGHS IN
THE MID 70S ACROSS MAJORITY OF AREA...AND MONDAY NIGHT IS COOLEST
BEHIND AFOREMENTIONED FROPA WITH LOWS IN LOW TO MID 40S BUT STILL
NOT LOW ENOUGH TO RAISE FROST/FREEZE CONCERNS.
BAKER
AVIATION...
06Z UPDATE...
SOUTHERLY FLOW JUST OFF THE SURFACE COMBINED WITH AN
INCREASINGLY MOIST ENVIRONMENT HAS LED TO THE DEVELOPMENT OF VFR
CIGS ACROSS MAINLY THE NORTHERN TAF SITES. CIGS WILL CONTINUE TO
INCREASE IN COVERAGE AREA THROUGH 15Z AND SHOULD BE HERE TO STAY
AS SHRA POTENTIAL INCREASES DURING THE LATE AFTERNOON HOURS.
TIMING OF THE TSRA IS TRICKY AS THERE IS MUCH UNCERTAINTY WITH THE
VARIOUS MODEL SOLUTIONS BUT FOR NOW PUT IT AT 23Z TO 03Z FOR THE
ATL SITES AND SLIGHTLY LATER FOR THE REMAINDER.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON TSRA TIMING.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 78 57 73 48 / 50 90 30 10
ATLANTA 76 56 68 49 / 90 100 20 10
BLAIRSVILLE 68 50 65 41 / 90 100 20 5
CARTERSVILLE 72 51 67 41 / 90 100 20 5
COLUMBUS 78 59 73 52 / 70 100 30 10
GAINESVILLE 71 54 69 48 / 90 100 20 10
MACON 80 63 73 51 / 40 80 50 10
ROME 71 49 67 41 / 90 100 10 5
PEACHTREE CITY 76 56 70 44 / 90 100 20 10
VIDALIA 80 66 76 60 / 20 70 60 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
718 AM EDT THU MAR 24 2016
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND OVER THE REGION TODAY. A COLD FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON FRIDAY...LIKELY STALLING JUST SOUTH
AND EAST OF THE REGION THROUGH SATURDAY. UNSETTLED WEATHER IS
EXPECTED SUNDAY...BEFORE A COLD FRONT PUSHES THROUGH THE AREA
MONDAY. DRY HIGH PRESSURE WILL THEN BUILD OVER THE REGION THROUGH
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INCREASED HIGHS 1-2 DEGREES ACROSS INTERIOR SOUTHEAST GEORGIA
WHERE BOTH THE RAP AND H3R ARE SHOWING A FEW MID 80S FOR HIGHS
THIS AFTERNOON. THE REST OF THE FORECAST IS ON TRACK.
UPPER RIDGING THAT HAS BEEN PRESENT ACROSS THE SOUTHEAST U.S. FOR
THE PAST SEVERAL DAYS WILL FINALLY BREAK DOWN TODAY IN RESPONSE
TO A POTENT STORM SYSTEM APPROACHING THE GREAT LAKES REGION.
ATLANTIC HIGH PRESSURE LOOKS TO HOLD ACROSS SOUTHEAST SOUTH
CAROLINA AND SOUTHEAST GEORGIA FOR FOR MUCH OF THE DAY BEFORE
FINALLY RETREATING TONIGHT IN RESPONSE TO AN APPROACHING COLD
FRONT. EXPECT DRY CONDITIONS TO PREVAIL FOR MOST AREAS THROUGH
SUNSET WITH MODELS SHOWING A STRONG SUBSIDENCE INVERSION HOLDING
JUST UNDER 750 HPA. THERE ARE SIGNALS IN BOTH THE SYNOPTIC AND
HIGHER RESOLUTION MESOSCALE MODELS THAT A NORTH-SOUTH ORIENTED
CONVERGENT MOISTURE CHANNEL COULD SETUP JUST OFF THE MIDDLE SOUTH
CAROLINA COAST LATER THIS MORNING. THIS COULD GENERATED ISOLATED
SHOWERS ACROSS THE COASTAL WATERS...SOME OF WHICH COULD MOVE
ONSHORE ACROSS THE MIDDLE/UPPER PORTIONS OF CHARLESTON COUNTY.
UPDRAFTS WITH THESE SHOWERS WILL BE SEVERELY CURTAILED GIVEN THE
PRESENCE OF THE STRONG SUBSIDENCE INVERSION...SO TSTMS APPEAR
UNLIKELY ATTM. WILL CARRY SLIGHT CHANCE POPS FOR CENTRAL AND UPPER
PORTIONS OF CHARLESTON COUNTY AS WELL AS EASTERN BERKELEY COUNTY
FOR TODAY WITH DRY CONDITIONS ELSEWHERE.
TEMPERATURES ARE POISED TO RISE QUICKLY AFTER SUNRISE WITH HIGHS
LIKELY TO WARM INTO THE LOWER 80S ALONG/WEST OF THE I-95
CORRIDOR. A BIT MORE CLOUD COVER AND POSSIBLY A FEW SHOWERS WILL
HELP LIMIT HIGHS TO THE UPPER 70S ACROSS MUCH OF THE CHARLESTON
TRI-COUNTY AREA AWAY FROM THE COAST. HIGHS AT THE BEACHES WILL
ONCE AGAIN BE LIMITED TO THE MID-UPPER 60S...EXCEPT AROUND 70 FOR
SOME GEORGIA BEACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
TONIGHT...A COLD FRONT WILL MOVE STEADILY EAST ACROSS THE DEEP
SOUTH OVERNIGHT AND WILL BE VERY NEAR THE FAR WESTERN ZONES BY
SUNRISE THURSDAY. NO SIGNIFICANT FORCING IS NOTED IN THE VARIOUS
00Z MODEL PROGNOSTICATIONS AND WITH THE POSSIBILITY OF CONVECTION
MOVING ACROSS THE NORTHEASTERN GULF POTENTIALLY DISRUPTING MOISTURE
TRANSPORT AHEAD OF THE FRONT...THE PROSPECTS FOR SIGNIFICANT
RAINFALL WILL REMAIN LOW THROUGH THE NIGHT. WILL CARRY 20-30
PERCENT POPS ACROSS THE FAR WESTERN ZONES BETWEEN MIDNIGHT AND
SUNRISE TO ACCOUNT FOR POSSIBLE SHOWER ACTIVITY ASSOCIATED WITH
THE FRONT ITSELF IMPACTING THOSE AREAS. IT WILL A WARM NIGHT WITH
LOWS ONLY DROPPING INTO THE MID 60 FOR MOST LOCATIONS.
FRIDAY...HIGH PRESSURE WILL RETREAT OVER THE WESTERN ATLANTIC AS A
COLD FRONT SLOWLY SHIFTS OVER THE AREA AND THEN STALLS SOUTH AND
EAST OF THE REGION LATE FRIDAY NIGHT. CHANCES OF SHOWERS AND A FEW
THUNDERSTORMS WILL BE POSSIBLE FOR MOST AREAS AS FROPA OCCURS.
SEVERE WEATHER IS NOT ANTICIPATED GIVEN LIMITED INSTABILITY DURING
THE TIME OF FROPA. DESPITE INCREASING CLOUD COVER AND PRECIP
ACTIVITY...HIGHS SHOULD PEAK IN THE LOW/MID 70S...WARMEST IN
SOUTHEAST GEORGIA.
SATURDAY AND SUNDAY...HIGH PRESSURE WILL ATTEMPT TO WEDGE SOUTHWARD
OVER NORTHERN AREAS ON SATURDAY BEHIND A COLD FRONT THAT STALLS JUST
SOUTH AND EAST OF THE AREA. HOWEVER...THE PATTERN WILL BE SHORT-
LIVED AS LOW PRESSURE BEGINS TO DEVELOP TO THE WEST/SOUTHWEST AND
SLOWLY TRACKS TOWARD THE SOUTHEAST UNITED STATES EARLY NEXT WEEK.
CHANCES OF SHOWERS WILL REMAIN IN THE FORECAST ON SATURDAY. A FEW
THUNDERSTORMS WILL ALSO BE POSSIBLE IN SOUTHEAST GEORGIA WHERE
LIMITED INSTABILITY DEVELOPS. HIGH TEMPS WILL RANGE IN THE UPPER 60S
NORTH...TO LOWER 70S SOUTH. BY SUNDAY...A GREATER CHANCE OF SHOWERS
AND THUNDERSTORMS WILL BE POSSIBLE AS A SERIES OF H5 SHORTWAVES
SHIFT OVER DEEP MOISTURE RESIDING IN THE SOUTHEASTERN UNITED STATES.
TEMPS SHOULD ALSO BE A FEW DEGREES WARMER THAN SATURDAY AS A
SOUTHERLY SFC FLOW RETURNS TO THE AREA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
A WET PATTERN WILL PERSIST INTO EARLY NEXT WEEK AS A SERIES OF H5
SHORTWAVES PASS OVER THE SOUTHEASTERN UNITED STATES IN ADVANCE OF A
LONGWAVE TROUGH. SHOWER AND THUNDERSTORM COVERAGE SHOULD BE GREATEST
SUNDAY INTO EARLY MONDAY WHEN DEEP MOISTURE CHARACTERIZED BY PWATS
BETWEEN 1.50 TO 1.75 INCHES ADVECTS INTO THE REGION AHEAD OF A COLD
FRONT APPROACHING FROM THE WEST. PRECIP ACTIVITY WILL LIKELY COME TO
AN END ONCE COLD FROPA OCCURS ON MONDAY. DRY AND COOLER HIGH
PRESSURE WILL THEN FOLLOW THE FRONT TUESDAY AND WEDNESDAY...WITH
HIGH TEMPS IN THE LOWER 70S AND OVERNIGHT LOWS IN THE UPPER 40S TO
LOWER 50S WELL INLAND. A WARMING TREND SHOULD THEN OCCUR ON THURSDAY
AS HIGH PRESSURE SLIDES OFFSHORE IN ADVANCE OF THE NEXT LOW PRESSURE
SYSTEM APPROACHING THE SOUTHEASTERN UNITED STATES.
&&
.AVIATION /11Z THURSDAY THROUGH MONDAY/...
VFR. COULD SEE A FEW SHOWERS NEAR THE KCHS TERMINAL LATER THIS
MORNING AS A NORTH- SOUTH ORIENTED MOISTURE CHANNEL SETS UP JUST
OFF THE LOWER SOUTH CAROLINA COAST. ANY ACTIVITY SHOULD REMAIN
EAST OF THE TERMINAL. THE RISK FOR MVFR CIGS WILL INCREASE
OVERNIGHT AS A COLD FRONT DRAWS CLOSER.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS ARE LIKELY FRIDAY
WITH SHOWERS AND THUNDERSTORMS DEVELOPING ALONG A PASSING COLD
FRONT. FLIGHT RESTRICTIONS COULD PERSIST THROUGH THE WEEKEND AND
INTO EARLY NEXT WEEK UNTIL A COLD FRONT PUSHES THROUGH THE REGION
ON MONDAY.
&&
.MARINE...
TONIGHT...SOUTHERLY WIND REGIME WILL REMAIN IN PLACE TODAY AS THE
AREA REMAINS ALONG THE WESTERN FLANKS OF ATLANTIC HIGH PRESSURE.
WILL LIKELY SEE ANOTHER GUSTY SEA BREEZE CIRCULATION IMPACT THE
LAND/SEA INTERFACE AND CHARLESTON HARBOR AGAIN THIS
AFTERNOON...BUT SPEEDS LOOK TO REMAIN A BIT LOWER THAN YESTERDAY.
COULD SEE A FEW HOURS OF 15 KT IN THE CHARLESTON HARBOR WITH 10-15
KT ELSEWHERE. SEAS WILL AVERAGE 2-3 FT.
TONIGHT...LOW-LEVEL JETTING WILL YIELD AN ENHANCED WIND FIELD
ACROSS THE WATERS TONIGHT AS A COLD FRONT APPROACHES FROM THE
WEST. SPEEDS LOOK TO PEAK 15-20 KT FOR MOST LEGS...ALTHOUGH THERE
COULD BE A FEW HOURS OF SPEEDS NEAR 20 KT ACROSS PARTS OF THE
GEORGIA OFFSHORE AND CHARLESTON COUNTY LEGS AFTER MIDNIGHT.
CONDITIONS LOOK MARGINAL FOR A SMALL CRAFT ADVISORY...ESPECIALLY
FOR THE GEORGIA OFFSHORE WATERS...SO FLAGS WILL NOT BE ISSUED WITH
THIS FORECAST CYCLE. SEAS WILL BUILD TO 3-5 FT.
FRIDAY THROUGH TUESDAY...MARGINAL SMALL CRAFT ADVISORY LEVEL
CONDITIONS ARE POSSIBLE IN OFFSHORE GEORGIA WATERS FRIDAY MORNING
BEFORE A COLD FRONT SHIFTS OFFSHORE. ELSEWHERE...WINDS SHOULD PEAK
BETWEEN 15 TO 20 KTS BEYOND 10 NM FROM THE COASTLINE. SEAS WILL ALSO
BUILD UP TO TO 3 TO 5 FT AHEAD OF THE FRONT. BY SATURDAY...A
NORTH/NORTHEAST WIND WILL BE IN PLACE AS HIGH PRESSURE TRIES TO
WEDGE SOUTHWARD BEHIND THE STALLING COLD FRONT. HOWEVER...LOW
PRESSURE IS EXPECTED TO DEVELOP WELL INLAND ON SUNDAY...RESULTING IN
EAST/SOUTHEAST WINDS EARLY NEXT WEEK. WINDS SHOULD PEAK AS HIGH AS
15 TO 20 KTS ON SUNDAY...AND COULD REMAIN ENHANCED THROUGH MONDAY AS
A COLD FRONT PUSHES OFFSHORE LATE. HIGH PRESSURE WILL THEN BUILD
OVER THE WATERS ON THROUGH THE MIDDLE OF NEXT WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
353 AM EDT THU MAR 24 2016
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND OVER THE REGION TODAY. A COLD FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON FRIDAY...LIKELY STALLING JUST SOUTH
AND EAST OF THE REGION THROUGH SATURDAY. UNSETTLED WEATHER IS
EXPECTED SUNDAY...BEFORE A COLD FRONT PUSHES THROUGH THE AREA
MONDAY. DRY HIGH PRESSURE WILL THEN BUILD OVER THE REGION THROUGH
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
UPPER RIDGING THAT HAS BEEN PRESENT ACROSS THE SOUTHEAST U.S. FOR
THE PAST SEVERAL DAYS WILL FINALLY BREAK DOWN TODAY IN RESPONSE
TO A POTENT STORM SYSTEM APPROACHING THE GREAT LAKES REGION.
ATLANTIC HIGH PRESSURE LOOKS TO HOLD ACROSS SOUTHEAST SOUTH
CAROLINA AND SOUTHEAST GEORGIA FOR FOR MUCH OF THE DAY BEFORE
FINALLY RETREATING TONIGHT IN RESPONSE TO AN APPROACHING COLD
FRONT. EXPECT DRY CONDITIONS TO PREVAIL FOR MOST AREAS THROUGH
SUNSET WITH MODELS SHOWING A STRONG SUBSIDENCE INVERSION HOLDING
JUST UNDER 750 HPA. THERE ARE SIGNALS IN BOTH THE SYNOPTIC AND
HIGHER RESOLUTION MESOSCALE MODELS THAT A NORTH-SOUTH ORIENTED
CONVERGENT MOISTURE CHANNEL COULD SETUP JUST OFF THE MIDDLE SOUTH
CAROLINA COAST LATER THIS MORNING. THIS COULD GENERATED ISOLATED
SHOWERS ACROSS THE COASTAL WATERS...SOME OF WHICH COULD MOVE
ONSHORE ACROSS THE MIDDLE/UPPER PORTIONS OF CHARLESTON COUNTY.
UPDRAFTS WITH THESE SHOWERS WILL BE SEVERELY CURTAILED GIVEN THE
PRESENCE OF THE STRONG SUBSIDENCE INVERSION...SO TSTMS APPEAR
UNLIKELY ATTM. WILL CARRY SLIGHT CHANCE POPS FOR CENTRAL AND UPPER
PORTIONS OF CHARLESTON COUNTY AS WELL AS EASTERN BERKELEY COUNTY
FOR TODAY WITH DRY CONDITIONS ELSEWHERE.
TEMPERATURES ARE POISED TO RISE QUICKLY AFTER SUNRISE WITH HIGHS
LIKELY TO WARM INTO THE LOWER 80S ALONG/WEST OF THE I-95
CORRIDOR. A BIT MORE CLOUD COVER AND POSSIBLY A FEW SHOWERS WILL
HELP LIMIT HIGHS TO THE UPPER 70S ACROSS MUCH OF THE CHARLESTON
TRI-COUNTY AREA AWAY FROM THE COAST. HIGHS AT THE BEACHES WILL
ONCE AGAIN BE LIMITED TO THE MID-UPPER 60S...EXCEPT AROUND 70 FOR
SOME GEORGIA BEACHES.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
TONIGHT...A COLD FRONT WILL MOVE STEADILY EAST ACROSS THE DEEP
SOUTH OVERNIGHT AND WILL BE VERY NEAR THE FAR WESTERN ZONES BY
SUNRISE THURSDAY. NO SIGNIFICANT FORCING IS NOTED IN THE VARIOUS
00Z MODEL PROGNOSTICATIONS AND WITH THE POSSIBILITY OF CONVECTION
MOVING ACROSS THE NORTHEASTERN GULF POTENTIALLY DISRUPTING MOISTURE
TRANSPORT AHEAD OF THE FRONT...THE PROSPECTS FOR SIGNIFICANT
RAINFALL WILL REMAIN LOW THROUGH THE NIGHT. WILL CARRY 20-30
PERCENT POPS ACROSS THE FAR WESTERN ZONES BETWEEN MIDNIGHT AND
SUNRISE TO ACCOUNT FOR POSSIBLE SHOWER ACTIVITY ASSOCIATED WITH
THE FRONT ITSELF IMPACTING THOSE AREAS. IT WILL A WARM NIGHT WITH
LOWS ONLY DROPPING INTO THE MID 60 FOR MOST LOCATIONS.
FRIDAY...HIGH PRESSURE WILL RETREAT OVER THE WESTERN ATLANTIC AS A
COLD FRONT SLOWLY SHIFTS OVER THE AREA AND THEN STALLS SOUTH AND
EAST OF THE REGION LATE FRIDAY NIGHT. CHANCES OF SHOWERS AND A FEW
THUNDERSTORMS WILL BE POSSIBLE FOR MOST AREAS AS FROPA OCCURS.
SEVERE WEATHER IS NOT ANTICIPATED GIVEN LIMITED INSTABILITY DURING
THE TIME OF FROPA. DESPITE INCREASING CLOUD COVER AND PRECIP
ACTIVITY...HIGHS SHOULD PEAK IN THE LOW/MID 70S...WARMEST IN
SOUTHEAST GEORGIA.
SATURDAY AND SUNDAY...HIGH PRESSURE WILL ATTEMPT TO WEDGE SOUTHWARD
OVER NORTHERN AREAS ON SATURDAY BEHIND A COLD FRONT THAT STALLS JUST
SOUTH AND EAST OF THE AREA. HOWEVER...THE PATTERN WILL BE SHORT-
LIVED AS LOW PRESSURE BEGINS TO DEVELOP TO THE WEST/SOUTHWEST AND
SLOWLY TRACKS TOWARD THE SOUTHEAST UNITED STATES EARLY NEXT WEEK.
CHANCES OF SHOWERS WILL REMAIN IN THE FORECAST ON SATURDAY. A FEW
THUNDERSTORMS WILL ALSO BE POSSIBLE IN SOUTHEAST GEORGIA WHERE
LIMITED INSTABILITY DEVELOPS. HIGH TEMPS WILL RANGE IN THE UPPER 60S
NORTH...TO LOWER 70S SOUTH. BY SUNDAY...A GREATER CHANCE OF SHOWERS
AND THUNDERSTORMS WILL BE POSSIBLE AS A SERIES OF H5 SHORTWAVES
SHIFT OVER DEEP MOISTURE RESIDING IN THE SOUTHEASTERN UNITED STATES.
TEMPS SHOULD ALSO BE A FEW DEGREES WARMER THAN SATURDAY AS A
SOUTHERLY SFC FLOW RETURNS TO THE AREA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
A WET PATTERN WILL PERSIST INTO EARLY NEXT WEEK AS A SERIES OF H5
SHORTWAVES PASS OVER THE SOUTHEASTERN UNITED STATES IN ADVANCE OF A
LONGWAVE TROUGH. SHOWER AND THUNDERSTORM COVERAGE SHOULD BE GREATEST
SUNDAY INTO EARLY MONDAY WHEN DEEP MOISTURE CHARACTERIZED BY PWATS
BETWEEN 1.50 TO 1.75 INCHES ADVECTS INTO THE REGION AHEAD OF A COLD
FRONT APPROACHING FROM THE WEST. PRECIP ACTIVITY WILL LIKELY COME TO
AN END ONCE COLD FROPA OCCURS ON MONDAY. DRY AND COOLER HIGH
PRESSURE WILL THEN FOLLOW THE FRONT TUESDAY AND WEDNESDAY...WITH
HIGH TEMPS IN THE LOWER 70S AND OVERNIGHT LOWS IN THE UPPER 40S TO
LOWER 50S WELL INLAND. A WARMING TREND SHOULD THEN OCCUR ON THURSDAY
AS HIGH PRESSURE SLIDES OFFSHORE IN ADVANCE OF THE NEXT LOW PRESSURE
SYSTEM APPROACHING THE SOUTHEASTERN UNITED STATES.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
VFR. LOW-LEVEL JET HAS SHOWN SIGNS OF WEAKENING OVER THE PAST 1-2
HOURS WITH THE LATEST RAP PROGS SHOWING LOW-LEVEL WIND SHEAR
CRITERIA DIMINISHING BY 06Z. WILL DROP MENTION FROM BOTH KCHS AND
KSAV WITH THE 06Z TAF CYCLE. SHALLOW GROUND FOG IS POSSIBLE JUST
BEFORE SUNRISE AT BOTH TERMINALS...BUT NO IMPACTS ARE ANTICIPATED.
COULD SEE A FEW SHOWERS NEAR THE KCHS TERMINAL LATER THIS MORNING
AS A NORTH- SOUTH ORIENTED MOISTURE CHANNEL SETS UP JUST OFF THE
LOWER SOUTH CAROLINA COAST. ANY ACTIVITY SHOULD REMAIN EAST OF THE
TERMINAL.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS ARE LIKELY FRIDAY
WITH SHOWERS AND THUNDERSTORMS DEVELOPING ALONG A PASSING COLD
FRONT. FLIGHT RESTRICTIONS COULD PERSIST THROUGH THE WEEKEND AND
INTO EARLY NEXT WEEK UNTIL A COLD FRONT PUSHES THROUGH THE REGION
ON MONDAY.
&&
.MARINE...
TONIGHT...SOUTHERLY WIND REGIME WILL REMAIN IN PLACE TODAY AS THE
AREA REMAINS ALONG THE WESTERN FLANKS OF ATLANTIC HIGH PRESSURE.
WILL LIKELY SEE ANOTHER GUSTY SEA BREEZE CIRCULATION IMPACT THE
LAND/SEA INTERFACE AND CHARLESTON HARBOR AGAIN THIS
AFTERNOON...BUT SPEEDS LOOK TO REMAIN A BIT LOWER THAN YESTERDAY.
COULD SEE A FEW HOURS OF 15 KT IN THE CHARLESTON HARBOR WITH 10-15
KT ELSEWHERE. SEAS WILL AVERAGE 2-3 FT.
TONIGHT...LOW-LEVEL JETTING WILL YIELD AN ENHANCED WIND FIELD
ACROSS THE WATERS TONIGHT AS A COLD FRONT APPROACHES FROM THE
WEST. SPEEDS LOOK TO PEAK 15-20 KT FOR MOST LEGS...ALTHOUGH THERE
COULD BE A FEW HOURS OF SPEEDS NEAR 20 KT ACROSS PARTS OF THE
GEORGIA OFFSHORE AND CHARLESTON COUNTY LEGS AFTER MIDNIGHT.
CONDITIONS LOOK MARGINAL FOR A SMALL CRAFT ADVISORY...ESPECIALLY
FOR THE GEORGIA OFFSHORE WATERS...SO FLAGS WILL NOT BE ISSUED WITH
THIS FORECAST CYCLE. SEAS WILL BUILD TO 3-5 FT.
FRIDAY THROUGH TUESDAY...MARGINAL SMALL CRAFT ADVISORY LEVEL
CONDITIONS ARE POSSIBLE IN OFFSHORE GEORGIA WATERS FRIDAY MORNING
BEFORE A COLD FRONT SHIFTS OFFSHORE. ELSEWHERE...WINDS SHOULD PEAK
BETWEEN 15 TO 20 KTS BEYOND 10 NM FROM THE COASTLINE. SEAS WILL ALSO
BUILD UP TO TO 3 TO 5 FT AHEAD OF THE FRONT. BY SATURDAY...A
NORTH/NORTHEAST WIND WILL BE IN PLACE AS HIGH PRESSURE TRIES TO
WEDGE SOUTHWARD BEHIND THE STALLING COLD FRONT. HOWEVER...LOW
PRESSURE IS EXPECTED TO DEVELOP WELL INLAND ON SUNDAY...RESULTING IN
EAST/SOUTHEAST WINDS EARLY NEXT WEEK. WINDS SHOULD PEAK AS HIGH AS
15 TO 20 KTS ON SUNDAY...AND COULD REMAIN ENHANCED THROUGH MONDAY AS
A COLD FRONT PUSHES OFFSHORE LATE. HIGH PRESSURE WILL THEN BUILD
OVER THE WATERS ON THROUGH THE MIDDLE OF NEXT WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/DPB
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1259 AM EDT THU MAR 24 2016
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND OVER THE REGION INTO THURSDAY. A COLD
FRONT WILL MOVE SLOWLY THROUGH THE AREA ON FRIDAY...LIKELY STALLING
JUST SOUTH AND EAST OF THE REGION THROUGH THE WEEKEND. UNSETTLED
WEATHER WILL BE POSSIBLE THROUGH THE WEEKEND...ESPECIALLY SUNDAY. A
COLD FRONT IS EXPECTED TO PUSH THROUGH THE AREA MONDAY...THEN HIGH
PRESSURE BUILDS FROM THE NORTH ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MADE MINOR ADJUSTMENTS TO OVERNIGHT LOWS AND HOURLY TEMPERATURES
PER GOING TRENDS. ANY SHOWER ACTIVITY THAT DEVELOPS OFF THE LOWER
SOUTH CAROLINA COAST SHOULD REMAIN OFFSHORE...ALTHOUGH AN ISOLATED
SHOWER OR TWO COULD APPROACH THE CHARLESTON COUNTY COAST BY
SUNRISE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
MODELS CONTINUE TO EXHIBIT A FAIR AMOUNT OF UNCERTAINTY LATER IN
THIS PERIOD. THE SETUP LOOKS SIMILAR TO LAST WEEKEND...WHEN THE
MODELS PREDICTED WET/HIGH POPS...BUT NOT MUCH OCCURRED. TRYING TO
SETTLE ON POPS AND PRECIP TIMING WAS VERY DIFFICULT. THEREFORE MADE
GENERALLY ONLY MINOR CHANGES TO THE PREVIOUS FORECAST FOR THIS
PERIOD.
THURSDAY...THIS WILL BE THE BEST WEATHER DAY OF THE PERIOD AS HIGH
PRESSURE CONTINUES TO RETREAT EASTWARD INTO THE ATLANTIC. LOW LEVEL
FLOW BECOMES SOUTHERLY...WHICH WILL HELP KEEP TEMPERATURES COOLER
NEAR THE COAST. NOT BUYING THE NAM...WHICH KEEPS TRYING TO BRING IN
PRECIP OFF OF THE ATLANTIC DURING THE DAY. KEPT SLIGHT CHANCE POPS
OVER THE WATERS AND GRADUAL INCREASE OF POPS FROM WEST TO EAST
DURING THE DAY. LATEST MODEL CONSENSUS SEEMS TO BE A LITTLE SLOWER
WITH BRINGING MOISTURE/PRECIP CHANCES BACK IN WITH THE APPROACHING
FRONT FROM THE WEST. THUS...HAVE MAINTAINED PREVIOUS FORECAST OF
HOLDING OFF MEASURABLE POPS THROUGH THE DAY. HIGH TEMPERATURES WILL
BE ABOVE NORMAL IN THE UPPER 70S TO AROUND 80.
THURSDAY NIGHT THROUGH FRIDAY...THE FRONT MOVES SLOWLY THROUGH THE
AREA DURING THIS PERIOD AND SEEMS TO STALL JUST OFFSHORE BY LATE
FRIDAY. BEST DEEP LAYER MOISTURE AND WEAK FORCING EXISTS DURING THIS
PERIOD. HAVE KEPT 30-50% POPS FOR THIS PERIOD...BUT CONFIDENCE IS
NOT VERY HIGH AS GUIDANCE HAS BEEN WAFFLING BACK AND FORTH ON POPS
FOR THIS PERIOD. STILL FEEL CHANCES FOR ANY SEVERE WEATHER IS VERY
LOW GIVEN LACK OF STRONG FORCING AND INSTABILITY. HOWEVER...THERE IS
ABUNDANT BULK SHEAR OF 30-50 KTS...WHICH COULD PRODUCE GUSTY WINDS
WITH ANY STRONGER SHOWERS OR ISOLATED THUNDERSTORMS. LOW
TEMPERATURES IN THE LOWER 60S THURSDAY NIGHT AND HIGHS IN THE MID
70S FRIDAY UNDER MOSTLY CLOUDY SKIES.
FRIDAY NIGHT...LATEST MODELS INDICATE THAT THERE MAYBE A BIT OF A
LULL IN PRECIP CHANCES...BUT AGAIN CONFIDENCE NOT VERY HIGH. HAVE
GONE WITH LOW END CHANCES CLOSER TO THE COAST AND THEN CHANCE OVER
THE ATLANTIC WATERS...AND SLIGHT CHANCE FURTHER INLAND. LOWS IN THE
MID TO UPPER 50S WITH MOSTLY CLOUDY/CLOUDY CONDITIONS.
SATURDAY...GLOBAL MODELS SHOW ANOTHER WAVE OF LOW PRESSURE MOVING
BACK TOWARD THE AREA FROM THE SOUTHWEST ALONG THE FRONT TO THE
SOUTH. BEST MOISTURE AND POTENTIAL FORCING APPEARS TO BE MAINLY OVER
THE SOUTHERN HALF OF THE AREA...WHICH IS WHERE WE KEPT LOW END
CHANCE POPS. HIGHS GENERALLY IN THE LOWER TO MID 70S...BUT WILL ALSO
DEPEND ON SKY COVER. EXPECT MOSTLY CLOUDY OVER THE SOUTH AND PARTLY
TO MOSTLY CLOUDY NORTH.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
TRENDS FAVOR A WETTER PATTERN OVER THE SOUTHEASTERN UNITED STATES
LATE WEEKEND INTO EARLY NEXT WEEK AS H5 SHORTWAVES PASS OVER A WEAK
WARM FRONT TRYING TO LIFT NORTH INTO THE AREA. SHOWER AND
THUNDERSTORM COVERAGE SHOULD BE GREATEST SUNDAY NIGHT INTO MONDAY
WHEN DEEP MOISTURE CHARACTERIZED BY PWATS BETWEEN 1.50 TO 1.75
INCHES ADVECTS TO THE REGION AHEAD OF A COLD FRONT APPROACHING FROM
THE WEST. EXPECT PRECIP ACTIVITY TO COME TO AN END AS THE COLD FRONT
PUSHES THROUGH THE AREA LATE MONDAY NIGHT INTO TUESDAY. DRY AND
SLIGHTLY COOLER HIGH PRESSURE WILL THEN FOLLOW THROUGH THE MIDDLE OF
NEXT WEEK.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
VFR. LOW-LEVEL JET HAS SHOWN SIGNS OF WEAKENING OVER THE PAST 1-2
HOURS WITH THE LATEST RAP PROGS SHOWING LOW-LEVEL WIND SHEAR
CRITERIA DIMINISHING BY 06Z. WILL DROP MENTION FROM BOTH KCHS AND
KSAV WITH THE 06Z TAF CYCLE. SHALLOW GROUND FOG IS POSSIBLE JUST
BEFORE SUNRISE AT BOTH TERMINALS...BUT NO IMPACTS ARE ANTICIPATED.
COULD SEE A FEW SHOWERS NEAR THE KCHS TERMINAL LATER THIS MORNING
AS A NORTH- SOUTH ORIENTED MOISTURE CHANNEL SETS UP JUST OFF THE
LOWER SOUTH CAROLINA COAST. ANY ACTIVITY SHOULD REMAIN EAST OF THE
TERMINAL.
EXTENDED AVIATION OUTLOOK...THURSDAY NIGHT THROUGH
SUNDAY...PERIODS OF FLIGHT RESTRICTIONS POSSIBLE...ESPECIALLY
THURSDAY NIGHT THROUGH FRIDAY WITH SHOWERS AND ISOLATED
THUNDERSTORMS. THERE MAY BE A BREAK WITH PRECIP CHANCES FOR FRIDAY
NIGHT...BUT LOW CLOUDS MAY STILL BE AN ISSUE. BEST CHANCES FOR
FLIGHT RESTRICTIONS WILL BE OVER KSAV SATURDAY AND SUNDAY AS LOW
PRESSURE POTENTIALLY CROSSES SOUTH OF THE AREA. MONDAY AND
TUESDAY...A RETURN TO VFR CONDITIONS AS A COLD FRONT LIKELY PUSHES
THROUGH THE AREA ON MONDAY WITH HIGH PRESSURE MONDAY NIGHT AND
TUESDAY.
&&
.MARINE...
OVERNIGHT...ON THE PERIPHERY OF ATLANTIC HIGH PRESSURE S/SE WINDS
10-15 KNOTS WILL VEER SLIGHTLY TOWARD THE S/SW LATER TONIGHT.
SEAS WILL RANGE FROM 1-2 FT NEARSHORE WATERS TO 2-3 FT BEYOND 20
NM.
THURSDAY...NO HIGHLIGHTS EXPECTED AS HIGH PRESSURE CONTINUES TO MOVE
EAST OF THE AREA WITH SOUTHERLY WINDS OF 15 KTS OR LESS AND SEAS 4
FT OR LESS.
THURSDAY NIGHT AND FRIDAY...MODELS STILL INDICATING THE POTENTIAL
FOR MARGINAL SCA CONDITIONS AHEAD OF A SLOWLY APPROACHING COLD FRONT
FROM THE WEST...ESPECIALLY THROUGH EARLY FRIDAY. GIVEN IT IS IN THE
THIRD AND FOURTH PERIOD OF THE FORECAST AND THERE IS STILL SOME
UNCERTAINTY...HAVE OPTED TO HOLD RAISING AN SCA FOR THIS PERIOD.
FRIDAY NIGHT THROUGH SUNDAY...NO HIGHLIGHTS EXPECTED. A COLD FRONT
STALLS JUST SOUTH AND EAST OF THE WATERS. WEAK WAVES OF LOW PRESSURE
POTENTIALLY MOVE ALONG THIS FRONT TO PRODUCE PERIODS OF SHOWERS AND
ISOLATED THUNDERSTORMS. WINDS GENERALLY SOUTHWEST AT 15 KTS OR LESS
AND SEAS 4 FT OR LESS...EXCEPT NORTH-NORTHEAST WINDS POSSIBLE NORTH
WATERS...DEPENDING ON WHERE SURFACE FRONT ENDS UP.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
212 PM CDT THU MAR 24 2016
.SHORT TERM...
212 PM CDT
THROUGH FRIDAY...
THE MAIN CONCERN WILL FOCUS ON THE PERIOD OF HEAVY SNOW EXPECTED TO
IMPACT PORTIONS OF NORTHERN ILLINOIS LATE THIS AFTERNOON AND VERY
EARLY THIS EVENING.
THE SURFACE LOW IS NOW SHIFTING INTO SOUTHEASTERN LOWER MICHIGAN
EARLY THIS AFTERNOON...AND THIS IS NOW ALLOWING THE WINDS TO PICK UP
OUT OF THE NORTH...AND COLDER AIR TO SINK SOUTHWARD OVER THE AREA.
THE MID-LEVEL DRY SLOT HAS ARRIVED INTO NORTHERN ILLINOIS...AND THIS
IS RESULTING IN A TEMPORARY END TO THE PRECIPITATION FOR MANY AREAS.
HOWEVER...WE ARE NOT DONE WITH THIS STORM SYSTEM YET...AS ATTENTION
IS NOW FOCUSED ON THE BAND OF MODERATE TO HEAVY SNOW THAT HAS
DEVELOPED OUT WEST NEAR THE MISSISSIPPI RIVER.
THIS AREA OF PRECIPITATION IS ASSOCIATED WITH A BAND OF STRONG
FRONTOGENESIS SETTING UP WITHIN THE SYSTEMS MID-LEVEL DEFORMATION
ZONE. MODEL GUIDANCE CONTINUES TO SUGGEST THAT THIS BAND OF FGEN IS
COINCIDING WITH THE THE PERIOD OF BEST MID AND UPPER LEVEL Q-VECTOR
CONVERGENCE ASSOCIATED WITH THE APPROACHING NEUTRAL TO NEGATIVELY
TILTED MID LEVEL DISTURBANCE. AS A RESULT...IT IS LIKELY THAT THIS
BAND OF MODERATE TO HEAVY SNOW WILL CONTINUE TO SHIFT EASTWARD
ACROSS FAR NORTHERN ILLINOIS THROUGH THE LATE AFTERNOON HOURS.
CURRENT OBSERVATIONS UNDER THIS BAND OF SNOW ARE INDICATING 1/2 TO
1/4 SM SNOW...SO I WILL BE INCLUDING HEAVY SNOW WORDING IN THE
FORECAST...AND WILL ALSO BE ISSUING AN SPS TO HIGHLIGHT THE VERY LOW
VISIBILITIES AND POSSIBLE QUICK SLUSHY ACCUMULATION EXPECTED DURING
THE AFTERNOON COMMUTE. OVERALL...THERE APPEARS TO BE A 2 TO 4 HOUR
WINDOW FOR THIS MODERATE TO HEAVY SNOW TO IMPACT FAR NORTHERN
ILLINOIS BEFORE THE FORCING WANES. GIVEN TEMPERATURES ARE
MARGINAL...AND WILL LIKELY COOL TO NEAR FREEZING UNDER THE HEAVY
PRECIP RATES...SNOW WILL LIKELY STRUGGLE TO ACCUMULATE MUCH ON AREA
ROADS...BUT A QUICK 1-2 INCHES IS CERTAINLY POSSIBLE ON GRASSY AND
ELEVATED SURFACES BEFORE THE SNOW ENDS EARLY THIS EVENING. THE BEST
CHANCE FOR SOME ACCUMULATIONS STILL APPEARS TO BE ALONG AND NORTH OF
A LINE FROM NEAR DIXON...NORTHEASTWARD TO WAUKEGAN.
KJB
&&
.LONG TERM...
354 AM CDT
SATURDAY NIGHT THROUGH THURSDAY...
FRIDAY THROUGH WEDNESDAY...
NICE WEATHER EXPECTED FRIDAY AS UPPER TROUGH FROM OUR CURRENT
MID-WEEK STORM SYSTEM LIFTS AWAY TO THE NORTHEAST AND LOW
AMPLITUDE SHORT WAVE RIDGE DEVELOPS OVERHEAD. SURFACE HIGH
PRESSURE DRIFTS EAST ACROSS THE CWA DURING THE DAY...WITH
SUBSIDENCE AND DRY COLUMN EXPECTED TO PRODUCE A GOOD DEAL OF
SUNSHINE. LIGHT WINDS IN THE VICINITY OF THE RIDGE AXIS THROUGH
EARLY AFTERNOON SHOULD ALLOW FOR TYPICAL SPRING LAKE BREEZE
DEVELOPMENT...THOUGH 925-950 MB MODEL THERMAL FIELDS INDICATE
INLAND AREAS SHOULD BE ABLE TO REACH HIGHS IN THE 48-52 DEGREE
RANGE. WINDS TURN SOUTHEAST BY EVENING...SETTING UP A SEASONABLY
COOL NIGHT AS MID AND HIGH CLOUDS EVENTUALLY INCREASE FROM THE
WEST AHEAD OF THE NEXT UPSTREAM DISTURBANCE.
THAT DISTURBANCE IS ACTUALLY A COUPLE OF INDIVIDUAL SHORT WAVES
WHICH HELP TO AMPLIFY A BROAD UPPER TROUGH ACROSS THE CENTRAL
CONUS THROUGH THE WEEKEND...ONE MOVING ACROSS THE UPPER
MISSISSIPPI VALLEY SATURDAY WHILE THE OTHER DIGS ACROSS THE
CENTRAL/SOUTHERN PLAINS AND EVENTUALLY INDUCES A DEEPENING AREA OF
LOW PRESSURE OVER THE OHIO VALLEY AND LOWER GREAT LAKES REGION BY
LATE SUNDAY AS IT BEGINS TO SWING NORTHEAST FROM THE BASE OF THE
TROUGH. MODEST HEIGHT FALLS DEVELOP INTO THE AREA SATURDAY MORNING
WITH THE APPROACH OF THE NORTHERN WAVE...THOUGH LOW LEVEL MOISTURE
RETURN IS LIMITED TO A NARROW CORRIDOR AHEAD OF THE COLD FRONT
WHICH TRAILS THE SURFACE LOW PRESSURE REFLECTION OVER WISCONSIN.
THUS PRECIP POTENTIAL DURING THE DAY SATURDAY LOOKS TO BE FOCUSED
ACROSS THE WESTERN HALF OF THE CWA AND PRIMARILY MIDDAY INTO THE
AFTERNOON WITH THE ADVANCING COLD FRONT. DESPITE INCREASING MID-
HIGH CLOUD COVER...SOUTH WINDS SHOULD HELP WARM TEMPS INTO THE 50S
OVER MUCH OF THE AREA AND TO AROUND 60 ACROSS THE SOUTH.
WRF...WHICH IS SLOWER WITH THE FRONT...INDICATES A BIT OF A
SOUTHEAST COMPONENT ALONG THE IL LAKESHORE WHICH MAY INDICATE A
VERY WEAK LAKE BREEZE.
FRONT PUSHES EAST ACROSS THE AREA SATURDAY EVENING...THOUGH
LATEST MODEL RUNS REALLY SCALE BACK PRECIP DURING THE EVENING AS
THE STRONGER SYNOPTIC FORCING BECOMES SPLIT TO OUR NORTH AND WELL
TO THE SOUTH. AS THE SOUTHERN LOW BEGINS TO DEVELOP AND DEEPEN
LATE SATURDAY NIGHT...FRONTOGENETIC FORCING ALONG THE SOUTH END OF
THE FRONT INCREASES AND ALLOWS RAIN TO DEVELOP FROM THE SOUTHWEST
INTO PARTS OF THE CWA BY SUNDAY MORNING. MEDIUM-RANGE GUIDANCE
REMAINS A LITTLE DIFFERENT WITH THE EXACT LOW TRACK ACROSS THE
MIDWEST SUNDAY/SUNDAY NIGHT...THOUGH GENERALLY FOCUS PRECIP ACROSS
THE SOUTHEAST HALF TO TWO THIRDS OF THE FORECAST AREA. PARTIAL
THICKNESS FIELDS INDICATE NEARLY ALL OF THE PRECIP WOULD FALL AS
RAIN...THOUGH THE SLIGHTLY FARTHER NORTHWEST TRACK OF THE 12Z
ECMWF WOULD SUPPORT A BRIEF MIX OR CHANGEOVER TO WET SNOW LATE
SUNDAY NIGHT OR EARLY MONDAY BEFORE PRECIP ENDS. CURRENT MODEL
PROGS GENERATE SOME SUBSTANTIAL QPF TOTALS ACROSS THE SOUTHEAST
PORTION OF THE FORECAST AREA THROUGH SUNDAY NIGHT...FROM 0.50
INCHES IN THE FARTHER SOUTHEAST GFS TO 1.25 INCHES IN THE ECMWF.
RISING HEIGHTS THEN DEVELOP INTO THE AREA MONDAY AS THE UPPER
TROUGH PULLS AWAY TO THE EAST...WITH GOOD MODEL CONSENSUS IN
DEVELOPING BROAD UPPER RIDGE ACROSS THE AREA THROUGH MID-WEEK
BEFORE THE NEXT AMPLIFIED UPPER TROUGH APPROACHES. SURFACE HIGH
PRESSURE OVER THE AREA MONDAY INTO TUESDAY WILL LIKELY SUPPORT
LAKE BREEZES BOTH DAYS...WITH TEMPS MODERATING FROM THE MID-40S TO
MID 50S EAST TO WEST MONDAY AND TO THE 55-60 RANGE ON TUESDAY.
SURFACE LOW DEVELOPING TO THE WEST OF THE AREA BY WEDNESDAY WOULD
SUPPORT CONTINUED SOUTH FLOW AND MILD TEMPS MID-WEEK...THOUGH WITH
AN INCREASING CHANCE OF RAIN.
RATZER
&&
.AVIATION...
FOR THE 18Z TAFS...
LOW PRESSURE WILL SHIFT EASTWARD SOUTH OF THE TERMINALS EARLY THIS
AFTERNOON. THIS WILL RESULT IN NORTHERLY WINDS...SHIFTING MORE NORTH-
NORTHWESTERLY LATER THIS AFTERNOON AND EVENING. WINDS GUSTS COULD
ALSO APPROACH 25 KT LATER THIS AFTERNOON AS THE SURFACE LOW SHIFTS
EASTWARD. OTHERWISE...IT APPEARS THAT SHOWERS WILL CONTINUE FOR THE
NEXT HOUR OR TWO AT THE EASTERN TERMINALS BEFORE ENDING FOR A
PERIOD. CIGS ALSO LOOK TO IMPROVE OVER THE EASTERN TAF SITES FOR A
COUPLE HOUR PERIOD THIS AFTERNOON BEFORE THEY DETERIORATE AGAIN
LATER THIS AFTERNOON. WE ARE STILL EXPECTING A BAND OF POTENTIALLY
HEAVY SNOW TO SET UP OVER NORTHERN ILLINOIS THROUGH THE AFTERNOON.
HOWEVER...AT THIS TIME IT APPEARS THAT KRFD WOULD STAND THE BEST
CHANCES AT SEEING LOW VSBYS AND POSSIBLE ACCUMULATIONS FROM THIS
BAND OF SNOW. FARTHER EAST...IT WILL TAKE UNTIL VERY LATE THIS
AFTERNOON...LIKELY AFTER 22-23 UTC BEFORE THE COLUMN COOLS ENOUGH TO
SUPPORT SOME SNOW. THEREFORE...IT APPEARS THAT THE EASTERN TERMINALS
MAY ONLY SEE A VERY SNORT PERIOD OF SOME SNOW BEFORE THE
PRECIPITATION ENDS EARLY THIS EVENING.
KJB
&&
.MARINE...
315 AM CDT
MODERATELY STRONG NORTHEASTERLY WINDS OF 30 TO 35 KT ARE IN PLACE
OVER MUCH OF LAKE MICHIGAN EARLY THIS MORNING AHEAD OF AN AREA
OF LOW PRESSURE OVER NORTHERN MISSOURI. WEAKER FLOW IS IN PLACE
ACROSS THE FAR SOUTHERN END OF LAKE MICHIGAN WHERE A FRONTAL
TROUGH IS IN PLACE. THE LOW WILL MOVE JUST SOUTH OF LAKE MICHIGAN
THIS AFTERNOON WITH WINDS BACKING TO THE NORTH AND GALES SPREADING
SOUTH ACROSS THE REMAINDER OF THE LAKE. GALES SHOULD DIMINISH
TONIGHT AND WINDS WILL BECOME LIGHT ON FRIDAY AS A RIDGE AXIS
MOVES OVER THE LAKE. FRESH SOUTHERLY FLOW RESUMES LATE FRIDAY INTO
SATURDAY AS THE RIDGE DEPARTS TO THE EAST ANOTHER FRONT MOVES
ACROSS LAKE MICHIGAN SATURDAY NIGHT INTO SUNDAY TURNING WINDS
NORTH AGAIN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 PM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779 UNTIL 4 AM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
121 PM CDT THU MAR 24 2016
.UPDATE...
Issued at 1113 AM CDT Thu Mar 24 2016
Surface low making its way across Central Illinois this morning,
dragging showers and scattered thunder with it. Forecast going
well overall with the timing of the precip. Showers on the back
side of the low limited in hi res models. Gusty winds following
the low as it deepens and tightens the pressure gradient. Cooler
afternoon with gusty winds anticipated and on track. No major
updates anticipated...but some small adjustments here and there
for hourly trends.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 323 AM CDT Thu Mar 24 2016
08z/3am surface analysis shows 997mb low over northern Missouri,
with stationary frontal boundary extending into north-central
Illinois. Based on latest obs, it appears the boundary extends from
near Macomb to just north of Pontiac. To the south of the front in
the warm sector, much of the KILX CWA has current temps in the lower
60s. Meanwhile to the north of the boundary, readings are only in
the lower 40s in Galesburg. A broken line of convection associated
with the approaching low developed across eastern Kansas/western
Missouri last evening...however that activity diminished as it
tracked northeastward and skirted the NW CWA around midnight. Latest
radar imagery shows very little going on across central Illinois:
however, showers are beginning to develop upstream and should spread
into the area over the next couple of hours. HRRR has been quite
persistent showing the showers becoming more widespread along/west
of I-55 after 09z/4am. As the low and accompanying cold front get
closer, showers and a few thunderstorms will develop across the
entire area early this morning. Have therefore carried categorical
PoPs across the board. The low will track to near the Chicago area
by midday, pulling the cold front through central Illinois and
pushing the widespread rain into Indiana at that time. Have
therefore lowered PoPs to just low chance across most of the area
this afternoon. The exception will be northwest of the Illinois
River, where deformation zone rain and snow showers will persist
through the afternoon. High temperatures will be achieved early in
the day, with readings falling steadily this afternoon. By mid
afternoon, temps will range from the upper 30s northwest of the
Illinois River...to the middle 50s near the Indiana border.
.LONG TERM...(Friday through Wednesday)
ISSUED AT 323 AM CDT Thu Mar 24 2016
As low pressure continues to lift into the eastern Great Lakes, a
few rain/snow showers may linger along/north of the I-74 corridor
early this evening before coming to an end before midnight. Skies
will initially be overcast, but will clear from west to east
overnight with lows dropping into the upper 20s and lower 30s. High
pressure will build into the region on Friday, leading to mostly
sunny and cool conditions with highs in the lower to middle 50s.
Once the high shifts off to the east, the next system will begin to
approach from the west over the weekend. Models have been
struggling with this feature for the past several days, and
agreement remains poor with the 00z Mar 24 run. The main issues
have been how much and how quickly an approaching short-wave trough
will amplify. Given the progressive flow pattern, have generally
preferred the weaker and faster solution. As such, will continue to
feature highest rain chances Sunday/Sunday night...followed by a
return to dry weather for Monday and Tuesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 115 PM CDT Thu Mar 24 2016
Low pressure center working through Central Illinois this
afternoon, southwesterly winds veering to more nw/northerly by end
of day. A brief shower on the back edge of the system possible,
mainly for PIA. But for the most part, low cigs dominate through
the overnight hours. Keeping MVFR cigs in place... and winds
remaining somewhat gusty in the tightening pressure gradient.
Clearing anticipated in the morning, although models are very
widely varied in timing.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1153 AM CDT THU MAR 24 2016
.UPDATE...
1153 AM CDT
THE MAIN CONCERN TODAY WILL BE IN REGARDS TO THE POTENTIAL FOR A
PERIOD OF HEAVY SNOW THIS AFTERNOON...PRIMARILY OVER FAR NORTHERN
ILLINOIS.
THE SURFACE LOW IS CENTERED OVER CENTRAL ILLINOIS...NEAR KBMI...WITH
THE QUASI-STATIONARY SURFACE BOUNDARY LOCATED JUST SOUTH OF LAKE
MICHIGAN. TEMPERATURES CONTINUE TO VARY WIDELY ON EITHER SIDE OF THE
FRONT...WITH 30S TO LOW 40S NORTH...AND 50S TO NEAR 60 SOUTH. PLENTY
OF RAIN IS ONGOING NORTH OF THE LOW OVER NORTHERN ILLINOIS. A LINE
OF THUNDERSTORMS IS ALSO SHIFTING EASTWARD ACROSS MY SOUTHERN
CWA...AND THIS OCCURRING JUST AHEAD OF THE MID-LEVEL DRY SLOT
PUNCHING EAST-NORTHEASTWARD INTO WESTERN ILLINOIS...PER THE LATEST
WATER VAPOR IMAGERY. WE EXPECT THIS LINE OF STORMS TO CONTINUE
EASTWARD OVER MAINLY THE SOUTHERN HALF OF THE AREA THROUGH EARLY
AFTERNOON...BEFORE THE DRY SLOT BEGINS TO SHIFT INTO CENTRAL
ILLINOIS.
OTHERWISE THE MAIN CONCERN THIS AFTERNOON IS THE CONTINUED POTENTIAL
FOR A BAND OF MODERATE TO POSSIBLY HEAVY SNOW...INITIALLY MIXING
WITH SLEET...OVER FAR NORTH CENTRAL ILLINOIS THIS AFTERNOON.
REGIONAL RADAR IMAGERY OVER THE PAST HOUR HAS REALLY SHOWN AN UPTICK
IN THE DEVELOPMENT OF PRECIPITATION OVER SOUTHEASTERN IOWA/FAR
NORTHERN MISSOURI WITHIN THE MID-LEVEL DEFORMATION ZONE. MODEL
GUIDANCE CONTINUES TO ADVERTISE A BAND OF FRONTOGENESIS SETTING UP
OVER NORTHERN ILLINOIS...WITHIN THIS DEFORMATION ZONE. GIVEN THIS
LOOKS TO COINCIDE WITH THE THE PERIOD OF BEST MID AND UPPER LEVEL Q-
VECTOR CONVERGENCE ASSOCIATED WITH THE APPROACHING NEUTRAL TO
NEGATIVELY TILTED MID LEVEL DISTURBANCE...IT APPEARS LIKELY THAT A
PERIOD OF MODERATE TO HEAVY WET SNOW WILL SET UP THROUGH THE
AFTERNOON OVER FAR NORTHERN ILLINOIS. THERE ALSO CONTINUES TO BE A
FEW LIGHTNING STRIKES OCCURRING WITHIN THIS DEVELOPING BAND OF
PRECIP. THEREFORE...WE CANNOT RULE OUT A RUMBLE OR TWO OF THUNDER
WITH SOME OF THIS HEAVIER SNOW. ACCUMULATIONS OF A FEW INCHES ARE
STILL POSSIBLE...ESPECIALLY ON GRASSY AREAS...BUT WE CURRENTLY
CONTINUE TO MENTION MORE CONSERVATIVE AMOUNTS AROUND AN
INCH...ESPECIALLY NORTH OF A LINE FROM NEAR DIXON...NORTHEASTWARD TO
WAUKEGAN. NEAR TERM TRENDS WILL CONTINUED TO BE MONITORED THIS
AFTERNOON TO SEE IF HIGHER AMOUNTS AND AN SPS ARE JUSTIFIED. ANY
SNOW SHOULD END QUICKLY THIS EVENING...WITH LITTLE IF ANY
ACCUMULATIONS EXPECTED INTO CHICAGO.
KJB
&&
.SHORT TERM...
354 AM CDT
TODAY AND TONIGHT...
STRONG SPRING STORM SYSTEM WORKING ITS WAY THROUGH THE MIDWEST
THIS MORNING. WATER VAPOR IMAGERY INDICATES THE MAIN MID-LEVEL
CIRCULATION WAS CENTERED NEAR KANSAS CITY AT 08Z...WITH A 998 MB
SURFACE LOW JUST NORTHEAST OF KMCI AND A STATIONARY FRONT
EXTENDING NORTHEASTWARD ACROSS NORTHERN IL AND INTO FAR NORTHWEST
INDIANA JUST SOUTH OF LAKE MICHIGAN. 08Z SURFACE OBS DEPICT A 26
DEGREE DIFFERENCE IN TEMPS ACROSS THE CWA...FROM 35 AT WAUKEGAN TO
61 AT RENSSELAER INDIANA. THIS WILL CONTINUE TO BE THE CASE TODAY
AS THE SURFACE LOW TRACKS ALONG THE FRONT...AND EVENTUALLY MOVES
EAST OF THE AREA LATE THIS AFTERNOON.
WFO LOT CWA IS CURRENTLY IN A LULL BETWEEN BAND OF SHOWERS AND
THUNDERSTORMS WHICH LIFTED ACROSS THE AREA OVER THE PAST SEVERAL
HOURS. AREA OF RAIN/EMBEDDED THUNDER OVER EASTERN MISSOURI AND
WEST CENTRAL IL IS EXPECTED TO SPREAD NORTHEAST BACK INTO THE AREA
THIS MORNING HOWEVER...AS DEEP FORCING INCREASES AHEAD OF
APPROACHING UPPER TROUGH AND STRONG MOISTURE TRANSPORT CONTINUES
PARTICULARLY INTO THE SOUTHEASTERN HALF OF THE FORECAST AREA. DRY
SLOT THEN PUSHES IN FROM THE SOUTHWEST MIDDAY/AFTERNOON WHICH
SHOULD CURTAIL PRECIP ACROSS THE SOUTH/SOUTHEAST...WHILE THE
TRAILING PORTION OF THE SYSTEM DEFORMATION ZONE PASSES ACROSS
NORTHERN ILLINOIS. FORECAST SOUNDINGS AND THICKNESS FIELDS
INDICATE THE COLUMN WILL COOL ENOUGH TO CHANGE LINGERING
DEFORMATION BAND PRECIP OVER TO SOME WET SNOW BEFORE ENDING EARLY
THIS EVENING...WITH A BRIEF PERIOD OF MIXED RAIN/SNOW/SLEET DURING
THE TRANSITION. GUIDANCE IS FAIRLY BULLISH WITH POTENTIAL FOR
ACCUMULATING SNOW ACROSS NORTH CENTRAL IL DURING THE LATE
AFTERNOON...AND WHILE SOME ACCUMULATION IS LIKELY...3-4 INCHES
INDICATED BY VARIOUS WRF RUNS MAY BE OVERDONE. EVEN SO...IT DOES
APPEAR THAT SOME ACCUMULATION CAN BE EXPECTED ACROSS FAR NORTH
CENTRAL AND NORTHERN IL WITH PERHAPS AN INCH ON GRASSY OR ELEVATED
SURFACES. PRECIP THEN WINDS DOWN QUICKLY THIS EVENING AS THE
SYSTEM DEPARTS TO THE EAST.
TEMPS TODAY ARE NOT EXPECTED TO STRAY TOO FAR FROM WHERE THEY ARE
NOW WITH THE FRONT BISECTING THE FORECAST AREA. SOME NORTHWARD
MOVEMENT OF THE BOUNDARY IS POSSIBLE ESPECIALLY SOUTH/SOUTHEAST OF
THE CHICAGO METRO AREA...THOUGH CONFIDENCE IS FAIRLY LOW ON EXACT
PLACEMENT. COLDER AIR SURGES IN THIS EVENING ON BLUSTERY NORTH
WINDS AS SKIES CLEAR OUT LATE.
RATZER
&&
.LONG TERM...
354 AM CDT
SATURDAY NIGHT THROUGH THURSDAY...
FRIDAY THROUGH WEDNESDAY...
NICE WEATHER EXPECTED FRIDAY AS UPPER TROUGH FROM OUR CURRENT
MID-WEEK STORM SYSTEM LIFTS AWAY TO THE NORTHEAST AND LOW
AMPLITUDE SHORT WAVE RIDGE DEVELOPS OVERHEAD. SURFACE HIGH
PRESSURE DRIFTS EAST ACROSS THE CWA DURING THE DAY...WITH
SUBSIDENCE AND DRY COLUMN EXPECTED TO PRODUCE A GOOD DEAL OF
SUNSHINE. LIGHT WINDS IN THE VICINITY OF THE RIDGE AXIS THROUGH
EARLY AFTERNOON SHOULD ALLOW FOR TYPICAL SPRING LAKE BREEZE
DEVELOPMENT...THOUGH 925-950 MB MODEL THERMAL FIELDS INDICATE
INLAND AREAS SHOULD BE ABLE TO REACH HIGHS IN THE 48-52 DEGREE
RANGE. WINDS TURN SOUTHEAST BY EVENING...SETTING UP A SEASONABLY
COOL NIGHT AS MID AND HIGH CLOUDS EVENTUALLY INCREASE FROM THE
WEST AHEAD OF THE NEXT UPSTREAM DISTURBANCE.
THAT DISTURBANCE IS ACTUALLY A COUPLE OF INDIVIDUAL SHORT WAVES
WHICH HELP TO AMPLIFY A BROAD UPPER TROUGH ACROSS THE CENTRAL
CONUS THROUGH THE WEEKEND...ONE MOVING ACROSS THE UPPER
MISSISSIPPI VALLEY SATURDAY WHILE THE OTHER DIGS ACROSS THE
CENTRAL/SOUTHERN PLAINS AND EVENTUALLY INDUCES A DEEPENING AREA OF
LOW PRESSURE OVER THE OHIO VALLEY AND LOWER GREAT LAKES REGION BY
LATE SUNDAY AS IT BEGINS TO SWING NORTHEAST FROM THE BASE OF THE
TROUGH. MODEST HEIGHT FALLS DEVELOP INTO THE AREA SATURDAY MORNING
WITH THE APPROACH OF THE NORTHERN WAVE...THOUGH LOW LEVEL MOISTURE
RETURN IS LIMITED TO A NARROW CORRIDOR AHEAD OF THE COLD FRONT
WHICH TRAILS THE SURFACE LOW PRESSURE REFLECTION OVER WISCONSIN.
THUS PRECIP POTENTIAL DURING THE DAY SATURDAY LOOKS TO BE FOCUSED
ACROSS THE WESTERN HALF OF THE CWA AND PRIMARILY MIDDAY INTO THE
AFTERNOON WITH THE ADVANCING COLD FRONT. DESPITE INCREASING MID-
HIGH CLOUD COVER...SOUTH WINDS SHOULD HELP WARM TEMPS INTO THE 50S
OVER MUCH OF THE AREA AND TO AROUND 60 ACROSS THE SOUTH.
WRF...WHICH IS SLOWER WITH THE FRONT...INDICATES A BIT OF A
SOUTHEAST COMPONENT ALONG THE IL LAKESHORE WHICH MAY INDICATE A
VERY WEAK LAKE BREEZE.
FRONT PUSHES EAST ACROSS THE AREA SATURDAY EVENING...THOUGH
LATEST MODEL RUNS REALLY SCALE BACK PRECIP DURING THE EVENING AS
THE STRONGER SYNOPTIC FORCING BECOMES SPLIT TO OUR NORTH AND WELL
TO THE SOUTH. AS THE SOUTHERN LOW BEGINS TO DEVELOP AND DEEPEN
LATE SATURDAY NIGHT...FRONTOGENETIC FORCING ALONG THE SOUTH END OF
THE FRONT INCREASES AND ALLOWS RAIN TO DEVELOP FROM THE SOUTHWEST
INTO PARTS OF THE CWA BY SUNDAY MORNING. MEDIUM-RANGE GUIDANCE
REMAINS A LITTLE DIFFERENT WITH THE EXACT LOW TRACK ACROSS THE
MIDWEST SUNDAY/SUNDAY NIGHT...THOUGH GENERALLY FOCUS PRECIP ACROSS
THE SOUTHEAST HALF TO TWO THIRDS OF THE FORECAST AREA. PARTIAL
THICKNESS FIELDS INDICATE NEARLY ALL OF THE PRECIP WOULD FALL AS
RAIN...THOUGH THE SLIGHTLY FARTHER NORTHWEST TRACK OF THE 12Z
ECMWF WOULD SUPPORT A BRIEF MIX OR CHANGEOVER TO WET SNOW LATE
SUNDAY NIGHT OR EARLY MONDAY BEFORE PRECIP ENDS. CURRENT MODEL
PROGS GENERATE SOME SUBSTANTIAL QPF TOTALS ACROSS THE SOUTHEAST
PORTION OF THE FORECAST AREA THROUGH SUNDAY NIGHT...FROM 0.50
INCHES IN THE FARTHER SOUTHEAST GFS TO 1.25 INCHES IN THE ECMWF.
RISING HEIGHTS THEN DEVELOP INTO THE AREA MONDAY AS THE UPPER
TROUGH PULLS AWAY TO THE EAST...WITH GOOD MODEL CONSENSUS IN
DEVELOPING BROAD UPPER RIDGE ACROSS THE AREA THROUGH MID-WEEK
BEFORE THE NEXT AMPLIFIED UPPER TROUGH APPROACHES. SURFACE HIGH
PRESSURE OVER THE AREA MONDAY INTO TUESDAY WILL LIKELY SUPPORT
LAKE BREEZES BOTH DAYS...WITH TEMPS MODERATING FROM THE MID-40S TO
MID 50S EAST TO WEST MONDAY AND TO THE 55-60 RANGE ON TUESDAY.
SURFACE LOW DEVELOPING TO THE WEST OF THE AREA BY WEDNESDAY WOULD
SUPPORT CONTINUED SOUTH FLOW AND MILD TEMPS MID-WEEK...THOUGH WITH
AN INCREASING CHANCE OF RAIN.
RATZER
&&
.AVIATION...
FOR THE 12Z TAFS...
A FRONTAL BOUNDARY STRETCHES FROM NEAR VYS TO GYY THIS MORNING
WITH NORTHEASTERLY FLOW AND LIFR CIGS NORTH OF THE BOUNDARY AND
SOUTHERLY WINDS AND HIGHER CIGS SOUTH OF THE FRONT. THE FRONT IS
PROGGED TO LIFT SLIGHTLY NORTH TO NEAR MDW BY MID MORNING THEN
SHOULD STALL AND EVENTUALLY START MOVING SOUTH AGAIN. WITH THAT
IN MIND HAVE ALL THE TERMINALS EXCEPT GYY IN NORTHEAST TO NORTH
FLOW THROUGH THE DAY TODAY WITH LIFR CIGS. DEPENDING ON HOW FAR
NORTH THE BOUNDARY GETS...COULD SEE SOME BREAKS IN THE CLOUDS AND
VARIABILITY IN THE WINDS AT MDW...BUT NOT ENOUGH CONFIDENCE TO PIN
ANYTHING DOWN FOR THE TAF.
SHOWERS CONTINUE TO SPREAD NORTH ACROSS NORTHERN ILLINOIS THIS
MORNING AND WILL BE IN PLACE THROUGH MUCH OF THE MORNING INTO
EARLY/MID AFTERNOON AS LOW PRESSURE MOVES ACROSS THE REGION. SOME
VERY MODEST INSTABILITY IS IN PLACE AHEAD OF THE LOW...AS FAR
NORTH AS SOUTHERN WISCONSIN WHICH IS RESULTING IN SOME LIGHTNING
ACTIVITY. FOR NOW IT APPEARS THE AXIS OF HIGHEST INSTABILITY LIES
ALONG AND JUST NORTH OF THE STATE LINE SO WILL KEEP TS OUT OF THE
TAF FOR NOW BUT CERTAINLY CANNOT RULE OUT THE POSSIBILITY TO HAVE
AN EMBEDDED THUNDERSTORM MOVE OVER ONE OF THE TERMINALS. AS THE
LOW PASSES BY MID AFTERNOON...WINDS WILL BACK TO THE NORTH-
NORTHWEST AND BECOME GUSTY. WHILE THIS SHOULD HELP INCREASE CIGS
SLIGHTLY TO HIGHER END IFR...THERE WILL ALSO BE A WINDOW WHEN
MIXED PRECIP OR SNOW IS POSSIBLE. LIGHT ACCUMULATIONS ARE POSSIBLE
FOR RFD WHICH WILL BE DEEPER IN THE COLD AIR. FOR THE CHICAGO
TERMINALS...DRY AIR MOVING IN ALOFT MAY RESULT IN SNOW/DRIZZLE OR
JUST DRIZZLE BEFORE PRECIP ENDS ALTOGETHER THIS EVENING. HIGH
PRESSURE WILL BUILD ACROSS THE AREA ON FRIDAY WHICH SHOULD HELP
IMPROVE CONDITIONS TO VFR AND PROVIDE LIGHT FLOW...ALTHOUGH AN
AFTERNOON LAKE BREEZE IS POSSIBLE.
BMD
&&
.MARINE...
315 AM CDT
MODERATELY STRONG NORTHEASTERLY WINDS OF 30 TO 35 KT ARE IN PLACE
OVER MUCH OF LAKE MICHIGAN EARLY THIS MORNING AHEAD OF AN AREA
OF LOW PRESSURE OVER NORTHERN MISSOURI. WEAKER FLOW IS IN PLACE
ACROSS THE FAR SOUTHERN END OF LAKE MICHIGAN WHERE A FRONTAL
TROUGH IS IN PLACE. THE LOW WILL MOVE JUST SOUTH OF LAKE MICHIGAN
THIS AFTERNOON WITH WINDS BACKING TO THE NORTH AND GALES SPREADING
SOUTH ACROSS THE REMAINDER OF THE LAKE. GALES SHOULD DIMINISH
TONIGHT AND WINDS WILL BECOME LIGHT ON FRIDAY AS A RIDGE AXIS
MOVES OVER THE LAKE. FRESH SOUTHERLY FLOW RESUMES LATE FRIDAY INTO
SATURDAY AS THE RIDGE DEPARTS TO THE EAST ANOTHER FRONT MOVES
ACROSS LAKE MICHIGAN SATURDAY NIGHT INTO SUNDAY TURNING WINDS
NORTH AGAIN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 PM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...4 PM THURSDAY TO 4 AM FRIDAY.
&&
$$
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
1117 AM CDT THU MAR 24 2016
.UPDATE...
Issued at 1113 AM CDT Thu Mar 24 2016
Surface low making its way across Central Illinois this morning,
dragging showers and scattered thunder with it. Forecast going
well overall with the timing of the precip. Showers on the back
side of the low limited in hi res models. Gusty winds following
the low as it deepens and tightens the pressure gradient. Cooler
afternoon with gusty winds anticipated and on track. No major
updates anticipated...but some small adjustments here and there
for hourly trends.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 323 AM CDT Thu Mar 24 2016
08z/3am surface analysis shows 997mb low over northern Missouri,
with stationary frontal boundary extending into north-central
Illinois. Based on latest obs, it appears the boundary extends from
near Macomb to just north of Pontiac. To the south of the front in
the warm sector, much of the KILX CWA has current temps in the lower
60s. Meanwhile to the north of the boundary, readings are only in
the lower 40s in Galesburg. A broken line of convection associated
with the approaching low developed across eastern Kansas/western
Missouri last evening...however that activity diminished as it
tracked northeastward and skirted the NW CWA around midnight. Latest
radar imagery shows very little going on across central Illinois:
however, showers are beginning to develop upstream and should spread
into the area over the next couple of hours. HRRR has been quite
persistent showing the showers becoming more widespread along/west
of I-55 after 09z/4am. As the low and accompanying cold front get
closer, showers and a few thunderstorms will develop across the
entire area early this morning. Have therefore carried categorical
PoPs across the board. The low will track to near the Chicago area
by midday, pulling the cold front through central Illinois and
pushing the widespread rain into Indiana at that time. Have
therefore lowered PoPs to just low chance across most of the area
this afternoon. The exception will be northwest of the Illinois
River, where deformation zone rain and snow showers will persist
through the afternoon. High temperatures will be achieved early in
the day, with readings falling steadily this afternoon. By mid
afternoon, temps will range from the upper 30s northwest of the
Illinois River...to the middle 50s near the Indiana border.
.LONG TERM...(Friday through Wednesday)
ISSUED AT 323 AM CDT Thu Mar 24 2016
As low pressure continues to lift into the eastern Great Lakes, a
few rain/snow showers may linger along/north of the I-74 corridor
early this evening before coming to an end before midnight. Skies
will initially be overcast, but will clear from west to east
overnight with lows dropping into the upper 20s and lower 30s. High
pressure will build into the region on Friday, leading to mostly
sunny and cool conditions with highs in the lower to middle 50s.
Once the high shifts off to the east, the next system will begin to
approach from the west over the weekend. Models have been
struggling with this feature for the past several days, and
agreement remains poor with the 00z Mar 24 run. The main issues
have been how much and how quickly an approaching short-wave trough
will amplify. Given the progressive flow pattern, have generally
preferred the weaker and faster solution. As such, will continue to
feature highest rain chances Sunday/Sunday night...followed by a
return to dry weather for Monday and Tuesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 545 AM CDT Thu Mar 24 2016
A large area of showers and isold tsra was tracking across the
forecast area this morning and will affect the cigs and vsbys
for a time as we head into early afternoon. Cigs have been
generally VFR overnight but with rain moving across the area
we expect at least some tempo MVFR cigs and vsbys in the heavier
areas of rain. Once the cold front pushes across the area...forecast
soundings suggest an increase in coverage of MVFR cigs as colder
air wraps into central Illinois this afternoon. Surface winds will
be south to southwest this morning at 12 to 17 kts with occasional
gusts up to 30 kts near the heavier showers. We look for winds to
become more southwest by 17z and then shift into the northwest
around 19z at PIA, 21z at SPI and by 01z at CMI. Once the MVFR
cigs move in behind the cold front, it appears they will linger
thru at least the evening hours, if not longer, based on the
latest forecast soundings.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
641 AM CDT THU MAR 24 2016
.SHORT TERM...
354 AM CDT
TODAY AND TONIGHT...
STRONG SPRING STORM SYSTEM WORKING ITS WAY THROUGH THE MIDWEST
THIS MORNING. WATER VAPOR IMAGERY INDICATES THE MAIN MID-LEVEL
CIRCULATION WAS CENTERED NEAR KANSAS CITY AT 08Z...WITH A 998 MB
SURFACE LOW JUST NORTHEAST OF KMCI AND A STATIONARY FRONT
EXTENDING NORTHEASTWARD ACROSS NORTHERN IL AND INTO FAR NORTHWEST
INDIANA JUST SOUTH OF LAKE MICHIGAN. 08Z SURFACE OBS DEPICT A 26
DEGREE DIFFERENCE IN TEMPS ACROSS THE CWA...FROM 35 AT WAUKEGAN TO
61 AT RENSSELAER INDIANA. THIS WILL CONTINUE TO BE THE CASE TODAY
AS THE SURFACE LOW TRACKS ALONG THE FRONT...AND EVENTUALLY MOVES
EAST OF THE AREA LATE THIS AFTERNOON.
WFO LOT CWA IS CURRENTLY IN A LULL BETWEEN BAND OF SHOWERS AND
THUNDERSTORMS WHICH LIFTED ACROSS THE AREA OVER THE PAST SEVERAL
HOURS. AREA OF RAIN/EMBEDDED THUNDER OVER EASTERN MISSOURI AND
WEST CENTRAL IL IS EXPECTED TO SPREAD NORTHEAST BACK INTO THE AREA
THIS MORNING HOWEVER...AS DEEP FORCING INCREASES AHEAD OF
APPROACHING UPPER TROUGH AND STRONG MOISTURE TRANSPORT CONTINUES
PARTICULARLY INTO THE SOUTHEASTERN HALF OF THE FORECAST AREA. DRY
SLOT THEN PUSHES IN FROM THE SOUTHWEST MIDDAY/AFTERNOON WHICH
SHOULD CURTAIL PRECIP ACROSS THE SOUTH/SOUTHEAST...WHILE THE
TRAILING PORTION OF THE SYSTEM DEFORMATION ZONE PASSES ACROSS
NORTHERN ILLINOIS. FORECAST SOUNDINGS AND THICKNESS FIELDS
INDICATE THE COLUMN WILL COOL ENOUGH TO CHANGE LINGERING
DEFORMATION BAND PRECIP OVER TO SOME WET SNOW BEFORE ENDING EARLY
THIS EVENING...WITH A BRIEF PERIOD OF MIXED RAIN/SNOW/SLEET DURING
THE TRANSITION. GUIDANCE IS FAIRLY BULLISH WITH POTENTIAL FOR
ACCUMULATING SNOW ACROSS NORTH CENTRAL IL DURING THE LATE
AFTERNOON...AND WHILE SOME ACCUMULATION IS LIKELY...3-4 INCHES
INDICATED BY VARIOUS WRF RUNS MAY BE OVERDONE. EVEN SO...IT DOES
APPEAR THAT SOME ACCUMULATION CAN BE EXPECTED ACROSS FAR NORTH
CENTRAL AND NORTHERN IL WITH PERHAPS AN INCH ON GRASSY OR ELEVATED
SURFACES. PRECIP THEN WINDS DOWN QUICKLY THIS EVENING AS THE
SYSTEM DEPARTS TO THE EAST.
TEMPS TODAY ARE NOT EXPECTED TO STRAY TOO FAR FROM WHERE THEY ARE
NOW WITH THE FRONT BISECTING THE FORECAST AREA. SOME NORTHWARD
MOVEMENT OF THE BOUNDARY IS POSSIBLE ESPECIALLY SOUTH/SOUTHEAST OF
THE CHICAGO METRO AREA...THOUGH CONFIDENCE IS FAIRLY LOW ON EXACT
PLACEMENT. COLDER AIR SURGES IN THIS EVENING ON BLUSTERY NORTH
WINDS AS SKIES CLEAR OUT LATE.
RATZER
&&
.LONG TERM...
354 AM CDT
SATURDAY NIGHT THROUGH THURSDAY...
FRIDAY THROUGH WEDNESDAY...
NICE WEATHER EXPECTED FRIDAY AS UPPER TROUGH FROM OUR CURRENT
MID-WEEK STORM SYSTEM LIFTS AWAY TO THE NORTHEAST AND LOW
AMPLITUDE SHORT WAVE RIDGE DEVELOPS OVERHEAD. SURFACE HIGH
PRESSURE DRIFTS EAST ACROSS THE CWA DURING THE DAY...WITH
SUBSIDENCE AND DRY COLUMN EXPECTED TO PRODUCE A GOOD DEAL OF
SUNSHINE. LIGHT WINDS IN THE VICINITY OF THE RIDGE AXIS THROUGH
EARLY AFTERNOON SHOULD ALLOW FOR TYPICAL SPRING LAKE BREEZE
DEVELOPMENT...THOUGH 925-950 MB MODEL THERMAL FIELDS INDICATE
INLAND AREAS SHOULD BE ABLE TO REACH HIGHS IN THE 48-52 DEGREE
RANGE. WINDS TURN SOUTHEAST BY EVENING...SETTING UP A SEASONABLY
COOL NIGHT AS MID AND HIGH CLOUDS EVENTUALLY INCREASE FROM THE
WEST AHEAD OF THE NEXT UPSTREAM DISTURBANCE.
THAT DISTURBANCE IS ACTUALLY A COUPLE OF INDIVIDUAL SHORT WAVES
WHICH HELP TO AMPLIFY A BROAD UPPER TROUGH ACROSS THE CENTRAL
CONUS THROUGH THE WEEKEND...ONE MOVING ACROSS THE UPPER
MISSISSIPPI VALLEY SATURDAY WHILE THE OTHER DIGS ACROSS THE
CENTRAL/SOUTHERN PLAINS AND EVENTUALLY INDUCES A DEEPENING AREA OF
LOW PRESSURE OVER THE OHIO VALLEY AND LOWER GREAT LAKES REGION BY
LATE SUNDAY AS IT BEGINS TO SWING NORTHEAST FROM THE BASE OF THE
TROUGH. MODEST HEIGHT FALLS DEVELOP INTO THE AREA SATURDAY MORNING
WITH THE APPROACH OF THE NORTHERN WAVE...THOUGH LOW LEVEL MOISTURE
RETURN IS LIMITED TO A NARROW CORRIDOR AHEAD OF THE COLD FRONT
WHICH TRAILS THE SURFACE LOW PRESSURE REFLECTION OVER WISCONSIN.
THUS PRECIP POTENTIAL DURING THE DAY SATURDAY LOOKS TO BE FOCUSED
ACROSS THE WESTERN HALF OF THE CWA AND PRIMARILY MIDDAY INTO THE
AFTERNOON WITH THE ADVANCING COLD FRONT. DESPITE INCREASING MID-
HIGH CLOUD COVER...SOUTH WINDS SHOULD HELP WARM TEMPS INTO THE 50S
OVER MUCH OF THE AREA AND TO AROUND 60 ACROSS THE SOUTH.
WRF...WHICH IS SLOWER WITH THE FRONT...INDICATES A BIT OF A
SOUTHEAST COMPONENT ALONG THE IL LAKESHORE WHICH MAY INDICATE A
VERY WEAK LAKE BREEZE.
FRONT PUSHES EAST ACROSS THE AREA SATURDAY EVENING...THOUGH
LATEST MODEL RUNS REALLY SCALE BACK PRECIP DURING THE EVENING AS
THE STRONGER SYNOPTIC FORCING BECOMES SPLIT TO OUR NORTH AND WELL
TO THE SOUTH. AS THE SOUTHERN LOW BEGINS TO DEVELOP AND DEEPEN
LATE SATURDAY NIGHT...FRONTOGENETIC FORCING ALONG THE SOUTH END OF
THE FRONT INCREASES AND ALLOWS RAIN TO DEVELOP FROM THE SOUTHWEST
INTO PARTS OF THE CWA BY SUNDAY MORNING. MEDIUM-RANGE GUIDANCE
REMAINS A LITTLE DIFFERENT WITH THE EXACT LOW TRACK ACROSS THE
MIDWEST SUNDAY/SUNDAY NIGHT...THOUGH GENERALLY FOCUS PRECIP ACROSS
THE SOUTHEAST HALF TO TWO THIRDS OF THE FORECAST AREA. PARTIAL
THICKNESS FIELDS INDICATE NEARLY ALL OF THE PRECIP WOULD FALL AS
RAIN...THOUGH THE SLIGHTLY FARTHER NORTHWEST TRACK OF THE 12Z
ECMWF WOULD SUPPORT A BRIEF MIX OR CHANGEOVER TO WET SNOW LATE
SUNDAY NIGHT OR EARLY MONDAY BEFORE PRECIP ENDS. CURRENT MODEL
PROGS GENERATE SOME SUBSTANTIAL QPF TOTALS ACROSS THE SOUTHEAST
PORTION OF THE FORECAST AREA THROUGH SUNDAY NIGHT...FROM 0.50
INCHES IN THE FARTHER SOUTHEAST GFS TO 1.25 INCHES IN THE ECMWF.
RISING HEIGHTS THEN DEVELOP INTO THE AREA MONDAY AS THE UPPER
TROUGH PULLS AWAY TO THE EAST...WITH GOOD MODEL CONSENSUS IN
DEVELOPING BROAD UPPER RIDGE ACROSS THE AREA THROUGH MID-WEEK
BEFORE THE NEXT AMPLIFIED UPPER TROUGH APPROACHES. SURFACE HIGH
PRESSURE OVER THE AREA MONDAY INTO TUESDAY WILL LIKELY SUPPORT
LAKE BREEZES BOTH DAYS...WITH TEMPS MODERATING FROM THE MID-40S TO
MID 50S EAST TO WEST MONDAY AND TO THE 55-60 RANGE ON TUESDAY.
SURFACE LOW DEVELOPING TO THE WEST OF THE AREA BY WEDNESDAY WOULD
SUPPORT CONTINUED SOUTH FLOW AND MILD TEMPS MID-WEEK...THOUGH WITH
AN INCREASING CHANCE OF RAIN.
RATZER
&&
.AVIATION...
FOR THE 12Z TAFS...
A FRONTAL BOUNDARY STRETCHES FROM NEAR VYS TO GYY THIS MORNING
WITH NORTHEASTERLY FLOW AND LIFR CIGS NORTH OF THE BOUNDARY AND
SOUTHERLY WINDS AND HIGHER CIGS SOUTH OF THE FRONT. THE FRONT IS
PROGGED TO LIFT SLIGHTLY NORTH TO NEAR MDW BY MID MORNING THEN
SHOULD STALL AND EVENTUALLY START MOVING SOUTH AGAIN. WITH THAT
IN MIND HAVE ALL THE TERMINALS EXCEPT GYY IN NORTHEAST TO NORTH
FLOW THROUGH THE DAY TODAY WITH LIFR CIGS. DEPENDING ON HOW FAR
NORTH THE BOUNDARY GETS...COULD SEE SOME BREAKS IN THE CLOUDS AND
VARIABILITY IN THE WINDS AT MDW...BUT NOT ENOUGH CONFIDENCE TO PIN
ANYTHING DOWN FOR THE TAF.
SHOWERS CONTINUE TO SPREAD NORTH ACROSS NORTHERN ILLINOIS THIS
MORNING AND WILL BE IN PLACE THROUGH MUCH OF THE MORNING INTO
EARLY/MID AFTERNOON AS LOW PRESSURE MOVES ACROSS THE REGION. SOME
VERY MODEST INSTABILITY IS IN PLACE AHEAD OF THE LOW...AS FAR
NORTH AS SOUTHERN WISCONSIN WHICH IS RESULTING IN SOME LIGHTNING
ACTIVITY. FOR NOW IT APPEARS THE AXIS OF HIGHEST INSTABILITY LIES
ALONG AND JUST NORTH OF THE STATE LINE SO WILL KEEP TS OUT OF THE
TAF FOR NOW BUT CERTAINLY CANNOT RULE OUT THE POSSIBILITY TO HAVE
AN EMBEDDED THUNDERSTORM MOVE OVER ONE OF THE TERMINALS. AS THE
LOW PASSES BY MID AFTERNOON...WINDS WILL BACK TO THE NORTH-
NORTHWEST AND BECOME GUSTY. WHILE THIS SHOULD HELP INCREASE CIGS
SLIGHTLY TO HIGHER END IFR...THERE WILL ALSO BE A WINDOW WHEN
MIXED PRECIP OR SNOW IS POSSIBLE. LIGHT ACCUMULATIONS ARE POSSIBLE
FOR RFD WHICH WILL BE DEEPER IN THE COLD AIR. FOR THE CHICAGO
TERMINALS...DRY AIR MOVING IN ALOFT MAY RESULT IN SNOW/DRIZZLE OR
JUST DRIZZLE BEFORE PRECIP ENDS ALTOGETHER THIS EVENING. HIGH
PRESSURE WILL BUILD ACROSS THE AREA ON FRIDAY WHICH SHOULD HELP
IMPROVE CONDITIONS TO VFR AND PROVIDE LIGHT FLOW...ALTHOUGH AN
AFTERNOON LAKE BREEZE IS POSSIBLE.
BMD
&&
.MARINE...
315 AM CDT
MODERATELY STRONG NORTHEASTERLY WINDS OF 30 TO 35 KT ARE IN PLACE
OVER MUCH OF LAKE MICHIGAN EARLY THIS MORNING AHEAD OF AN AREA
OF LOW PRESSURE OVER NORTHERN MISSOURI. WEAKER FLOW IS IN PLACE
ACROSS THE FAR SOUTHERN END OF LAKE MICHIGAN WHERE A FRONTAL
TROUGH IS IN PLACE. THE LOW WILL MOVE JUST SOUTH OF LAKE MICHIGAN
THIS AFTERNOON WITH WINDS BACKING TO THE NORTH AND GALES SPREADING
SOUTH ACROSS THE REMAINDER OF THE LAKE. GALES SHOULD DIMINISH
TONIGHT AND WINDS WILL BECOME LIGHT ON FRIDAY AS A RIDGE AXIS
MOVES OVER THE LAKE. FRESH SOUTHERLY FLOW RESUMES LATE FRIDAY INTO
SATURDAY AS THE RIDGE DEPARTS TO THE EAST ANOTHER FRONT MOVES
ACROSS LAKE MICHIGAN SATURDAY NIGHT INTO SUNDAY TURNING WINDS
NORTH AGAIN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 PM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...4 PM THURSDAY TO 4 AM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
545 AM CDT THU MAR 24 2016
.SHORT TERM...(Today and tonight)
ISSUED AT 323 AM CDT Thu Mar 24 2016
08z/3am surface analysis shows 997mb low over northern Missouri,
with stationary frontal boundary extending into north-central
Illinois. Based on latest obs, it appears the boundary extends from
near Macomb to just north of Pontiac. To the south of the front in
the warm sector, much of the KILX CWA has current temps in the lower
60s. Meanwhile to the north of the boundary, readings are only in
the lower 40s in Galesburg. A broken line of convection associated
with the approaching low developed across eastern Kansas/western
Missouri last evening...however that activity diminished as it
tracked northeastward and skirted the NW CWA around midnight. Latest
radar imagery shows very little going on across central Illinois:
however, showers are beginning to develop upstream and should spread
into the area over the next couple of hours. HRRR has been quite
persistent showing the showers becoming more widespread along/west
of I-55 after 09z/4am. As the low and accompanying cold front get
closer, showers and a few thunderstorms will develop across the
entire area early this morning. Have therefore carried categorical
PoPs across the board. The low will track to near the Chicago area
by midday, pulling the cold front through central Illinois and
pushing the widespread rain into Indiana at that time. Have
therefore lowered PoPs to just low chance across most of the area
this afternoon. The exception will be northwest of the Illinois
River, where deformation zone rain and snow showers will persist
through the afternoon. High temperatures will be achieved early in
the day, with readings falling steadily this afternoon. By mid
afternoon, temps will range from the upper 30s northwest of the
Illinois River...to the middle 50s near the Indiana border.
.LONG TERM...(Friday through Wednesday)
ISSUED AT 323 AM CDT Thu Mar 24 2016
As low pressure continues to lift into the eastern Great Lakes, a
few rain/snow showers may linger along/north of the I-74 corridor
early this evening before coming to an end before midnight. Skies
will initially be overcast, but will clear from west to east
overnight with lows dropping into the upper 20s and lower 30s. High
pressure will build into the region on Friday, leading to mostly
sunny and cool conditions with highs in the lower to middle 50s.
Once the high shifts off to the east, the next system will begin to
approach from the west over the weekend. Models have been
struggling with this feature for the past several days, and
agreement remains poor with the 00z Mar 24 run. The main issues
have been how much and how quickly an approaching short-wave trough
will amplify. Given the progressive flow pattern, have generally
preferred the weaker and faster solution. As such, will continue to
feature highest rain chances Sunday/Sunday night...followed by a
return to dry weather for Monday and Tuesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 545 AM CDT Thu Mar 24 2016
A large area of showers and isold tsra was tracking across the
forecast area this morning and will affect the cigs and vsbys
for a time as we head into early afternoon. Cigs have been
generally VFR overnight but with rain moving across the area
we expect at least some tempo MVFR cigs and vsbys in the heavier
areas of rain. Once the cold front pushes across the area...forecast
soundings suggest an increase in coverage of MVFR cigs as colder
air wraps into central Illinois this afternoon. Surface winds will
be south to southwest this morning at 12 to 17 kts with occasional
gusts up to 30 kts near the heavier showers. We look for winds to
become more southwest by 17z and then shift into the northwest
around 19z at PIA, 21z at SPI and by 01z at CMI. Once the MVFR
cigs move in behind the cold front, it appears they will linger
thru at least the evening hours, if not longer, based on the
latest forecast soundings.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
356 AM CDT THU MAR 24 2016
.SHORT TERM...
354 AM CDT
TODAY AND TONIGHT...
STRONG SPRING STORM SYSTEM WORKING ITS WAY THROUGH THE MIDWEST
THIS MORNING. WATER VAPOR IMAGERY INDICATES THE MAIN MID-LEVEL
CIRCULATION WAS CENTERED NEAR KANSAS CITY AT 08Z...WITH A 998 MB
SURFACE LOW JUST NORTHEAST OF KMCI AND A STATIONARY FRONT
EXTENDING NORTHEASTWARD ACROSS NORTHERN IL AND INTO FAR NORTHWEST
INDIANA JUST SOUTH OF LAKE MICHIGAN. 08Z SURFACE OBS DEPICT A 26
DEGREE DIFFERENCE IN TEMPS ACROSS THE CWA...FROM 35 AT WAUKEGAN TO
61 AT RENSSELAER INDIANA. THIS WILL CONTINUE TO BE THE CASE TODAY
AS THE SURFACE LOW TRACKS ALONG THE FRONT...AND EVENTUALLY MOVES
EAST OF THE AREA LATE THIS AFTERNOON.
WFO LOT CWA IS CURRENTLY IN A LULL BETWEEN BAND OF SHOWERS AND
THUNDERSTORMS WHICH LIFTED ACROSS THE AREA OVER THE PAST SEVERAL
HOURS. AREA OF RAIN/EMBEDDED THUNDER OVER EASTERN MISSOURI AND
WEST CENTRAL IL IS EXPECTED TO SPREAD NORTHEAST BACK INTO THE AREA
THIS MORNING HOWEVER...AS DEEP FORCING INCREASES AHEAD OF
APPROACHING UPPER TROUGH AND STRONG MOISTURE TRANSPORT CONTINUES
PARTICULARLY INTO THE SOUTHEASTERN HALF OF THE FORECAST AREA. DRY
SLOT THEN PUSHES IN FROM THE SOUTHWEST MIDDAY/AFTERNOON WHICH
SHOULD CURTAIL PRECIP ACROSS THE SOUTH/SOUTHEAST...WHILE THE
TRAILING PORTION OF THE SYSTEM DEFORMATION ZONE PASSES ACROSS
NORTHERN ILLINOIS. FORECAST SOUNDINGS AND THICKNESS FIELDS
INDICATE THE COLUMN WILL COOL ENOUGH TO CHANGE LINGERING
DEFORMATION BAND PRECIP OVER TO SOME WET SNOW BEFORE ENDING EARLY
THIS EVENING...WITH A BRIEF PERIOD OF MIXED RAIN/SNOW/SLEET DURING
THE TRANSITION. GUIDANCE IS FAIRLY BULLISH WITH POTENTIAL FOR
ACCUMULATING SNOW ACROSS NORTH CENTRAL IL DURING THE LATE
AFTERNOON...AND WHILE SOME ACCUMULATION IS LIKELY...3-4 INCHES
INDICATED BY VARIOUS WRF RUNS MAY BE OVERDONE. EVEN SO...IT DOES
APPEAR THAT SOME ACCUMULATION CAN BE EXPECTED ACROSS FAR NORTH
CENTRAL AND NORTHERN IL WITH PERHAPS AN INCH ON GRASSY OR ELEVATED
SURFACES. PRECIP THEN WINDS DOWN QUICKLY THIS EVENING AS THE
SYSTEM DEPARTS TO THE EAST.
TEMPS TODAY ARE NOT EXPECTED TO STRAY TOO FAR FROM WHERE THEY ARE
NOW WITH THE FRONT BISECTING THE FORECAST AREA. SOME NORTHWARD
MOVEMENT OF THE BOUNDARY IS POSSIBLE ESPECIALLY SOUTH/SOUTHEAST OF
THE CHICAGO METRO AREA...THOUGH CONFIDENCE IS FAIRLY LOW ON EXACT
PLACEMENT. COLDER AIR SURGES IN THIS EVENING ON BLUSTERY NORTH
WINDS AS SKIES CLEAR OUT LATE.
RATZER
&&
.LONG TERM...
354 AM CDT
SATURDAY NIGHT THROUGH THURSDAY...
FRIDAY THROUGH WEDNESDAY...
NICE WEATHER EXPECTED FRIDAY AS UPPER TROUGH FROM OUR CURRENT
MID-WEEK STORM SYSTEM LIFTS AWAY TO THE NORTHEAST AND LOW
AMPLITUDE SHORT WAVE RIDGE DEVELOPS OVERHEAD. SURFACE HIGH
PRESSURE DRIFTS EAST ACROSS THE CWA DURING THE DAY...WITH
SUBSIDENCE AND DRY COLUMN EXPECTED TO PRODUCE A GOOD DEAL OF
SUNSHINE. LIGHT WINDS IN THE VICINITY OF THE RIDGE AXIS THROUGH
EARLY AFTERNOON SHOULD ALLOW FOR TYPICAL SPRING LAKE BREEZE
DEVELOPMENT...THOUGH 925-950 MB MODEL THERMAL FIELDS INDICATE
INLAND AREAS SHOULD BE ABLE TO REACH HIGHS IN THE 48-52 DEGREE
RANGE. WINDS TURN SOUTHEAST BY EVENING...SETTING UP A SEASONABLY
COOL NIGHT AS MID AND HIGH CLOUDS EVENTUALLY INCREASE FROM THE
WEST AHEAD OF THE NEXT UPSTREAM DISTURBANCE.
THAT DISTURBANCE IS ACTUALLY A COUPLE OF INDIVIDUAL SHORT WAVES
WHICH HELP TO AMPLIFY A BROAD UPPER TROUGH ACROSS THE CENTRAL
CONUS THROUGH THE WEEKEND...ONE MOVING ACROSS THE UPPER
MISSISSIPPI VALLEY SATURDAY WHILE THE OTHER DIGS ACROSS THE
CENTRAL/SOUTHERN PLAINS AND EVENTUALLY INDUCES A DEEPENING AREA OF
LOW PRESSURE OVER THE OHIO VALLEY AND LOWER GREAT LAKES REGION BY
LATE SUNDAY AS IT BEGINS TO SWING NORTHEAST FROM THE BASE OF THE
TROUGH. MODEST HEIGHT FALLS DEVELOP INTO THE AREA SATURDAY MORNING
WITH THE APPROACH OF THE NORTHERN WAVE...THOUGH LOW LEVEL MOISTURE
RETURN IS LIMITED TO A NARROW CORRIDOR AHEAD OF THE COLD FRONT
WHICH TRAILS THE SURFACE LOW PRESSURE REFLECTION OVER WISCONSIN.
THUS PRECIP POTENTIAL DURING THE DAY SATURDAY LOOKS TO BE FOCUSED
ACROSS THE WESTERN HALF OF THE CWA AND PRIMARILY MIDDAY INTO THE
AFTERNOON WITH THE ADVANCING COLD FRONT. DESPITE INCREASING MID-
HIGH CLOUD COVER...SOUTH WINDS SHOULD HELP WARM TEMPS INTO THE 50S
OVER MUCH OF THE AREA AND TO AROUND 60 ACROSS THE SOUTH.
WRF...WHICH IS SLOWER WITH THE FRONT...INDICATES A BIT OF A
SOUTHEAST COMPONENT ALONG THE IL LAKESHORE WHICH MAY INDICATE A
VERY WEAK LAKE BREEZE.
FRONT PUSHES EAST ACROSS THE AREA SATURDAY EVENING...THOUGH
LATEST MODEL RUNS REALLY SCALE BACK PRECIP DURING THE EVENING AS
THE STRONGER SYNOPTIC FORCING BECOMES SPLIT TO OUR NORTH AND WELL
TO THE SOUTH. AS THE SOUTHERN LOW BEGINS TO DEVELOP AND DEEPEN
LATE SATURDAY NIGHT...FRONTOGENETIC FORCING ALONG THE SOUTH END OF
THE FRONT INCREASES AND ALLOWS RAIN TO DEVELOP FROM THE SOUTHWEST
INTO PARTS OF THE CWA BY SUNDAY MORNING. MEDIUM-RANGE GUIDANCE
REMAINS A LITTLE DIFFERENT WITH THE EXACT LOW TRACK ACROSS THE
MIDWEST SUNDAY/SUNDAY NIGHT...THOUGH GENERALLY FOCUS PRECIP ACROSS
THE SOUTHEAST HALF TO TWO THIRDS OF THE FORECAST AREA. PARTIAL
THICKNESS FIELDS INDICATE NEARLY ALL OF THE PRECIP WOULD FALL AS
RAIN...THOUGH THE SLIGHTLY FARTHER NORTHWEST TRACK OF THE 12Z
ECMWF WOULD SUPPORT A BRIEF MIX OR CHANGEOVER TO WET SNOW LATE
SUNDAY NIGHT OR EARLY MONDAY BEFORE PRECIP ENDS. CURRENT MODEL
PROGS GENERATE SOME SUBSTANTIAL QPF TOTALS ACROSS THE SOUTHEAST
PORTION OF THE FORECAST AREA THROUGH SUNDAY NIGHT...FROM 0.50
INCHES IN THE FARTHER SOUTHEAST GFS TO 1.25 INCHES IN THE ECMWF.
RISING HEIGHTS THEN DEVELOP INTO THE AREA MONDAY AS THE UPPER
TROUGH PULLS AWAY TO THE EAST...WITH GOOD MODEL CONSENSUS IN
DEVELOPING BROAD UPPER RIDGE ACROSS THE AREA THROUGH MID-WEEK
BEFORE THE NEXT AMPLIFIED UPPER TROUGH APPROACHES. SURFACE HIGH
PRESSURE OVER THE AREA MONDAY INTO TUESDAY WILL LIKELY SUPPORT
LAKE BREEZES BOTH DAYS...WITH TEMPS MODERATING FROM THE MID-40S TO
MID 50S EAST TO WEST MONDAY AND TO THE 55-60 RANGE ON TUESDAY.
SURFACE LOW DEVELOPING TO THE WEST OF THE AREA BY WEDNESDAY WOULD
SUPPORT CONTINUED SOUTH FLOW AND MILD TEMPS MID-WEEK...THOUGH WITH
AN INCREASING CHANCE OF RAIN.
RATZER
&&
.AVIATION...
FOR THE 06Z TAFS...
A LINE OF THUNDERSTORMS IS RACING EAST ACROSS THE MISSISSIPPI RIVER
LATE THIS EVENING AND IS PROGGED TO MOVE ACROSS THE NORTHERN
ILLINOIS AND NORTHWEST INDIANA TERMINALS A LITTLE BEFORE 07Z FOR RFD
AND ROUGHLY 730-9Z FOR THE CHICAGO AREA TERMINALS. BEHIND THIS LINE
OF THUNDERSTORMS...MID LEVEL DRY SLOT WILL PUNCH OVERHEAD AND SHOULD
ALLOW PRECIP TO DIMINISH TO A DRIZZLE FOR A FEW HOURS BEFORE STEADY
RAIN SPREADS BACK IN LATE TONIGHT THROUGH THE MORNING MONDAY.
FRONTAL BOUNDARY AT 05Z STRETCHES FROM NEAR PNT NNE TO NEAR VPZ AND
IS PROGGED LIFT NORTH INTO CHICAGO LATE TONIGHT INTO EARLY THURSDAY.
WINDS SHOULD LIGHTEN UP A BIT AS THE FRONTAL TROUGH NEARS. LOOKS
LIKE ORD IS A GOOD BET TO STAY NORTH OF THE FRONT WITH NORTHEAST
WINDS WHILE EXPECT GYY TO HAVE FROPA WITH WINDS TURNING SOUTHERLY.
IT WILL BE VERY CLOSE TO MDW BETWEEN ROUGHLY 08-12Z BEFORE THE
BOUNDARY STARTS TO MOVE SOUTH AGAIN. THIS MEANS A HIGH DEGREE OF
UNCERTAINTY IN WIND DIRECTION FOR MDW...THOUGH WOULD EXPECT SPEEDS
TO BE LESS THAN 10 KT.
LOW PRESSURE WILL PASS NEAR OR SOUTH OF THE TERMINALS MIDDAY
THURSDAY WITH WINDS BACKING TO THE NORTH AND EVENTUALLY NORTHWEST
LATE AFTERNOON INTO THE EVENING. COOLER AIR WILL WORK INTO THE
REGION BEHIND THE LOW WITH PRECIP TYPE BECOMING MORE OF A CONCERN AS
THE DAY WEARS ON. RFD HAS THE BEST CHANCE TO SEE SOME LIGHT
ACCUMULATIONS FROM MID AFTERNOON INTO EARLY EVENING BEFORE DRIER AIR
FINALLY ARRIVES. FOR THE CHICAGO AREA...THERMAL PROFILES ARE MORE
MARGINAL AND MAY ONLY SEE A RAIN/SNOW MIX BEFORE DRIER AIR MOVES IN
AND WE LOSE ICE CRYSTALS IN THE COLUMN.
BMD
&&
.MARINE...
315 AM CDT
MODERATELY STRONG NORTHEASTERLY WINDS OF 30 TO 35 KT ARE IN PLACE
OVER MUCH OF LAKE MICHIGAN EARLY THIS MORNING AHEAD OF AN AREA
OF LOW PRESSURE OVER NORTHERN MISSOURI. WEAKER FLOW IS IN PLACE
ACROSS THE FAR SOUTHERN END OF LAKE MICHIGAN WHERE A FRONTAL
TROUGH IS IN PLACE. THE LOW WILL MOVE JUST SOUTH OF LAKE MICHIGAN
THIS AFTERNOON WITH WINDS BACKING TO THE NORTH AND GALES SPREADING
SOUTH ACROSS THE REMAINDER OF THE LAKE. GALES SHOULD DIMINISH
TONIGHT AND WINDS WILL BECOME LIGHT ON FRIDAY AS A RIDGE AXIS
MOVES OVER THE LAKE. FRESH SOUTHERLY FLOW RESUMES LATE FRIDAY INTO
SATURDAY AS THE RIDGE DEPARTS TO THE EAST ANOTHER FRONT MOVES
ACROSS LAKE MICHIGAN SATURDAY NIGHT INTO SUNDAY TURNING WINDS
NORTH AGAIN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS
UNTIL 4 PM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...4 PM THURSDAY TO 4 AM FRIDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
323 AM CDT THU MAR 24 2016
.SHORT TERM...(Today and tonight)
ISSUED AT 323 AM CDT Thu Mar 24 2016
08z/3am surface analysis shows 997mb low over northern Missouri,
with stationary frontal boundary extending into north-central
Illinois. Based on latest obs, it appears the boundary extends from
near Macomb to just north of Pontiac. To the south of the front in
the warm sector, much of the KILX CWA has current temps in the lower
60s. Meanwhile to the north of the boundary, readings are only in
the lower 40s in Galesburg. A broken line of convection associated
with the approaching low developed across eastern Kansas/western
Missouri last evening...however that activity diminished as it
tracked northeastward and skirted the NW CWA around midnight. Latest
radar imagery shows very little going on across central Illinois:
however, showers are beginning to develop upstream and should spread
into the area over the next couple of hours. HRRR has been quite
persistent showing the showers becoming more widespread along/west
of I-55 after 09z/4am. As the low and accompanying cold front get
closer, showers and a few thunderstorms will develop across the
entire area early this morning. Have therefore carried categorical
PoPs across the board. The low will track to near the Chicago area
by midday, pulling the cold front through central Illinois and
pushing the widespread rain into Indiana at that time. Have
therefore lowered PoPs to just low chance across most of the area
this afternoon. The exception will be northwest of the Illinois
River, where deformation zone rain and snow showers will persist
through the afternoon. High temperatures will be achieved early in
the day, with readings falling steadily this afternoon. By mid
afternoon, temps will range from the upper 30s northwest of the
Illinois River...to the middle 50s near the Indiana border.
&&
.LONG TERM...(Friday through Wednesday)
ISSUED AT 323 AM CDT Thu Mar 24 2016
As low pressure continues to lift into the eastern Great Lakes, a
few rain/snow showers may linger along/north of the I-74 corridor
early this evening before coming to an end before midnight. Skies
will initially be overcast, but will clear from west to east
overnight with lows dropping into the upper 20s and lower 30s. High
pressure will build into the region on Friday, leading to mostly
sunny and cool conditions with highs in the lower to middle 50s.
Once the high shifts off to the east, the next system will begin to
approach from the west over the weekend. Models have been
struggling with this feature for the past several days, and
agreement remains poor with the 00z Mar 24 run. The main issues
have been how much and how quickly an approaching short-wave trough
will amplify. Given the progressive flow pattern, have generally
preferred the weaker and faster solution. As such, will continue to
feature highest rain chances Sunday/Sunday night...followed by a
return to dry weather for Monday and Tuesday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1140 PM CDT Wed Mar 23 2016
Frontal boundary has remained stationary from just south of PIA
to just north of BMI this evening. Winds at PIA remained E, with S
winds at the remaining terminals. As low pressure continues to
approach from the west, winds will eventually shift veer to SW by
mid-day and then become W-NW from late afternoon near PIA to mid-
evening at CMI.
A line of storms approaching Knox county appears to be tracking to
the NW of Peoria. Showers are on track to affect the PIA airport
between 0530z and 07z before lifting off to the northeast. After
that, the HRRR and RAP models point toward the development of a
line of showers and storms along the Illinois River Valley around
10z/5am. The line is expected to expand eastward, then with the
back edge of rain lingering near the IL river until the low
pressure center reaches PIA around 17z and progresses into Indiana
by 20z. A trough of low pressure trailing behind the low along
I-74 will be the focus for light rain showers through the
afternoon for the northern terminals of PIA and BMI. The other
terminals will see precip come to an end from west to east between
19z at SPI to 21z at CMI. If any precip continues near PIA to BMI
until 00z/7pm, light snow could develop. However, no snow
accumulation is expected.
The aviation conditions will dip from VFR to MVFR as precipitation
develops, then remain MVFR possibly until the end of the taf
period. The southern terminals will have the better potential of
seeing cigs improve to VFR during the afternoon as the dry slot
punches across SPI/DEC/CMI. Then, wrap around moisture and a
subsidence inversion could produce MVFR clouds again at all TAF
sites after sunset tomorrow evening.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1212 AM CDT THU MAR 24 2016
.UPDATE...
949 PM CDT
MAIN CHANGES TO EVENING/OVERNIGHT FORECAST WAS TO TWEAK
TEMPERATURE AND WIND TRENDS BASED ON OBSERVATIONS OF QUASI-
STATIONARY FRONT POSITION...WHICH WAS LOCATED IN A MEANDERING
FASHION FROM JUST SOUTH OF PNT TO IKK TO SOUTH OF VPA TO JUST
NORTH OF OXI AS OF 0200 UTC. AS SURFACE LOW TRACKS NORTHEAST
OVERNIGHT INTO EARLY THURSDAY...PRESSURE FALLS WILL ENABLE FRONT
TO LIFT SLOWLY NORTH AS WARM FRONT TOWARD I-80 CORRIDOR...THOUGH
WILL MAKE BETTER NORTHWARD PROGRESS WITH EASTWARD EXTENT IN CWA.
STEEPER LAPSE RATES/COOLING ALOFT ASSOCIATED WITH IMPRESSIVE
CLOSED LOW ON W/V IMAGERY SHOULD ENABLE CAPPING IN PLACE TO
DIMINISH...WITH SLIGHT TO CHANCE THUNDER MENTION
MAINTAINED...BETTER CHANCE SOUTH OF THE FRONT. THERE HAS BEEN A
SLOW DOWNWARD TREND IN LIGHTNING COVERAGE OFF TO THE WEST.
THUS...REGARDING STRONG/SEVERE PROSPECTS OVERNIGHT/EARLY
THURSDAY...CANNOT COMPLETELY RULE IT OUT IN FAR SOUTHWEST
CWA. HOWEVER...IT APPEARS BETTER CHANCE FOR AN ISOLATED STRONG TO
SEVERE STORM WILL BE SOUTHWEST OF THE CWA WHERE SLIGHTLY HIGHER
INSTABILITY WILL RESIDE.
THERE HAS NOT BEEN MUCH IN WAY OF SIGNIFICANT VISIBILITY
REDUCTIONS THIS EVENING NORTH OF FRONT...BUT WITH LOW DEWPOINT
SPREADS MAINTAINED PATCHY FOG MENTION. BETTER POTENTIAL FOR AREAS
OF FOG...EVEN LOCALLY DENSE...COULD OCCUR JUST NORTH OF FRONT AND
CLOSER TO LAKE MICHIGAN IN PREDAWN HOURS THROUGH MID MORNING.
INCREASED FOG COVERAGE TO AREAS OF FOG IN GRIDS FOR THAT AREA.
FINALLY...REGARDING ACCUMULATING SNOW POTENTIAL ON THURSDAY
AFTERNOON...DID NOT MAKE BIG CHANGES TO GRIDS...BUT CONTINUE TO
BE CONCERNED FOR A PERIOD OF HEAVY SNOW RIGHT AFTER CHANGEOVER FOR
PARTS OF FAR NORTHERN ILLINOIS ALONG THE 700 MB DEFORMATION AXIS
PATH. ALONG WITH THE ROCKFORD AREA...THIS COULD INCLUDE NORTHERN
PORTIONS OF THE CHICAGO METRO AREA DURING THE AFTERNOON COMMUTE.
LATEST 00Z NAM IS ROUGHLY IN LINE WITH 18Z GFS IN THIS
SCENARIO...SO WILL NEED TO CLOSELY MONITOR OBSERVATIONAL TRENDS.
THINK THAT THE WINDOW WILL BE BRIEF AND PLACEMENT OF THE BAND
COULD VARY...BUT WITHIN IT...AMOUNTS OF 1"+ IN A SHORT TIME COULD
OCCUR/ESPECIALLY ON COLDER SURFACES. IF BAND PLACEMENT VERIFIES
CLOSE TO NAM/GFS...CANNOT RULE OUT LOCAL AMOUNTS UP TO 2-3". WILL
BRIEF MIDNIGHT SHIFT ON THESE CONCERNS.
RC
&&
.SHORT TERM...
331 PM CDT
THROUGH FRIDAY...
A SURFACE FRONTAL BOUNDARY REMAINS NEARLY STATIONARY OVER MY
SOUTHERN COUNTIES THIS AFTERNOON...WITH A SHARP CONTRAST IN
TEMPERATURES ON EITHER SIDE OF IT. TO THE NORTH...MAINLY 40S TO LOW
50S ARE PROMINENT...WITH THE EXCEPTION OF NEAR LAKE MICHIGAN WHERE
TEMPERATURES HAVE BEEN NEAR 40. SOUTH OF THE FRONT...TEMPERATURES
ARE IN THE LOW TO MID 60S. PRECIPITATION THROUGH THE DAY HAS BEEN
MAINLY TO OUR NORTH OF WISCONSIN...WHERE A BAND OF FRONTOGENESIS HAS
BEEN THE PRIMARILY DRIVER. HOWEVER...RADAR IMAGERY OVER THE PAST HOUR
HAS SHOWN AN UPTICK IN MAINLY VERY LIGHT RAIN OR DRIZZLE OVER
NORTHWESTERN ILLINOIS. THIS APPEARS TO BE THE MAIN STORY OVER THE
AREA THIS EVENING...WITH ONLY SOME LIGHT SHOWERS OR DRIZZLE
IMPACTING THE AREA.
SHOWERS...AND EVEN SOME THUNDERSTORM CHANCES SHOULD INCREASE FROM
WEST TO EAST OVER THE AREA OVERNIGHT INTO EARLY THURSDAY MORNING AS
THE MAIN STORM SYSTEM...NOW OVER THE KANSAS...SHIFTS TOWARDS
NORTHERN ILLINOIS. AS THIS LOW APPROACHES OVERNIGHT...THE SURFACE
FRONT WILL LIKELY SHIFT NORTHWARD UP NEAR THE I80 CORRIDOR BY
DAYBREAK THURSDAY. AS A RESULT...TEMPERATURES WILL LIKELY COME UP A
FEW DEGREES OVERNIGHT WHERE THE WARM FRONT PASSES. THE BEST CHANCE
OF THUNDERSTORMS LOOKS TO COME LATER TONIGHT INTO THURSDAY. THERE
ALSO CONTINUES TO BE A THREAT OF A FEW STRONG...TO POSSIBLY
MARGINALLY SEVERE STORMS OVER SOUTHERN PORTIONS OF THE AREA (MAINLY
SOUTH OF I-80) LATE TONIGHT THROUGH EARLY THURSDAY AFTERNOON.
OVERALL INSTABILITY WILL NOT BE OVERLY IMPRESSIVE...BUT THE
COMBINATION OF STRONG DEEP LAYER SHEAR AND THE DYNAMIC FORCING WITH
THE STORM SYSTEM COULD STILL SUPPORT A FEW STRONG STORMS AHEAD OF
THE COLD FRONT.
FARTHER TO THE NORTH...MAINLY OVER NORTHWESTERN AND PORTIONS OF FAR
NORTH CENTRAL ILLINOIS...THINGS COULD GET INTERESTING THURSDAY
AFTERNOON AS IT APPEARS A GOOD MID-LEVEL DEFORMATION ZONE MAY SET UP
OVER THIS AREA ALONG AND NEAR THE PATH OF THE 700 MB LOW. THIS COULD
SUPPORT A BAND OF MODERATE TO HEAVY WET SNOW OVER PORTIONS OF
NORTHWESTERN AND NORTH CENTRAL ILLINOIS...ESPECIALLY BY MID TO LATE
THURSDAY AFTERNOON. GIVEN THE POTENTIAL OF A BAND OF STRONG FGEN
SETTING UP WITHIN THIS DEFORMATION ZONE...ALONG WITH THE FACT THAT
LOOKS TO COINCIDE WITH THE PERIOD OF BEST MID-UPPER LEVEL Q-VECTOR
CONVERGENCE...ASSOCIATED WITH THE STRONG MID-LEVEL WAVE...THIS COULD
SET UP A PERIOD OF HEAVY SNOW. WE CAN ALSO NOT TOTALLY RULE OUT THE
POSSIBILITY OF CONVECTIVE SNOW RATES...ESPECIALLY CONSIDERING ALL OF
THE LIGHTNING AND REPORTS OF TSSN OVER WESTERN NEBRASKA OVER THE
PAST FEW HOURS. IN SPITE OF THIS POTENTIAL FOR SNOW...POSSIBLY
IMPACTING AREAS IN AND AROUND THE ROCKFORD AREA THURSDAY
AFTERNOON...UNCERTAINTY ON IMPACTS REMAIN LOW AT THIS TIME. THIS IS
DUE TO THE FACT THAT THESE BANDS OF HEAVY SNOW TEND TO BE
NARROW...AND GIVEN THAT GROUND TEMPS HAVE BEEN WARM LATELY IT WILL
TAKE HEAVY SNOW RATES IN ORDER TO GET ACCUMULATIONS...AND THIS MAY
END UP ONLY OCCURRING ON GRASSY AREAS AND ELEVATED SURFACES...WHERE
A COUPLE INCHES OF WET SNOW IS CERTAINLY POSSIBLE. THEREFORE...AT
THIS TIME I WILL MENTION THE POTENTIAL OF SOME HEAVY SNOW IN THE
HWO.
SOME SNOW COULD GET INTO THE CHICAGO AREA BY EARLY THURSDAY EVENING
BEFORE ENDING...BUT IT APPEARS UNLIKELY THAT ANY REAL ACCUMULATIONS
WOULD MATERIALIZE OUTSIDE OF NORTH CENTRAL ILLINOIS.
KJB
&&
.LONG TERM...
153 PM CDT
SATURDAY NIGHT THROUGH WEDNESDAY...
SATURDAY NIGHT THROUGH SUNDAY NIGHT...LOW PRESSURE CURRENTLY IN THE
GULF OF ALASKA WILL BE MOVING OUT OF THE SOUTHERN ROCKIES INTO THE
CENTRAL PLAINS ON SATURDAY NIGHT. A PORTION OF THE ENERGY WITH THIS
LOW WILL BE ABSORBED INTO THE NORTHERN STREAM UPPER LEVEL FLOW
PATTERN. THIS INTRODUCES CONSIDERABLE UNCERTAINTY INTO THE FORECAST
FOR SUNDAY INTO EARLY MONDAY AS FAR AS THE STRENGTH OF THE SURFACE
LOW THAT WILL DEVELOP...AND HOW PROGRESSIVE THE PATTERN WILL BE.
APPEARS THERE WILL BE SEMI-DECENT CHANCES FOR RAIN WITH THE LEAD
WAVE SATURDAY NIGHT...AND MODELS ARE IN PRETTY GOOD AGREEMENT ON
THIS. THE DIFFERENCES APPEAR MORE SO SUNDAY AS THE ECMWF IN ITS PAST
FEW RUNS DEVELOPS A STRONGER SURFACE LOW...AND THUS A MORE
SIGNIFICANT DEFORMATION BAND OF PRECIPITATION SUNDAY/SUNDAY NIGHT
WHEREAS THE GFS HAS A MORE PROGRESSIVE OPEN WAVE AND JUST SOME LIGHT
RAIN IF ANYTHING. THE GEM IS SOMEWHERE IN THE MIDDLE AND CLOSER TO
THE MORE FAVORED GUIDANCE FROM THE NATIONAL CENTERS...BUT ENSEMBLE
GUIDANCE STILL EXHIBITS QUITE A BIT OF SPREAD. THIS MIDDLE ROAD
SUGGESTS A DECENT BAND OF RAIN SUNDAY THEN SHIFTING EAST SUNDAY
NIGHT. WILL CONTINUE WITH THE MODEL BLEND WHICH GIVES HIGH END
CHANCE OF RAIN...WHICH COULD CERTAINLY BE HIGHER IF THE SLOWER
SOLUTIONS PREVAIL.
MONDAY... WEAK HIGH PRESSURE RETURNS FOR MONDAY RESULTING IN A
SEAONABLY COOL BUT DRY DAY WITH MORE SUNSHINE.
TUESDAY INTO MIDWEEK...ANOTHER DEEP UPPER TROUGH WILL BUILD ACROSS
THE WESTERN CONTINENTAL UNITED STATES. EXPECT SOME WARMING ON
TUESDAY CLOSER TO NORMS IN THE LOWER 50S...BUT WITH LOW PRESSURE
DEVELOPING TO OUR WEST ONSHORE WINDS WILL KEEP AREAS CLOSER TO THE
LAKE A BIT COLDER THAN NORMAL. THE UPPER LEVEL TROUGH WILL MOVE
EASTWARD INCREASING CHANCES FOR MILD AND WETTER WEATHER LATER IN THE
WEEK.
KMD
&&
.AVIATION...
FOR THE 06Z TAFS...
A LINE OF THUNDERSTORMS IS RACING EAST ACROSS THE MISSISSIPPI RIVER
LATE THIS EVENING AND IS PROGGED TO MOVE ACROSS THE NORTHERN
ILLINOIS AND NORTHWEST INDIANA TERMINALS A LITTLE BEFORE 07Z FOR RFD
AND ROUGHLY 730-9Z FOR THE CHICAGO AREA TERMINALS. BEHIND THIS LINE
OF THUNDERSTORMS...MID LEVEL DRY SLOT WILL PUNCH OVERHEAD AND SHOULD
ALLOW PRECIP TO DIMINISH TO A DRIZZLE FOR A FEW HOURS BEFORE STEADY
RAIN SPREADS BACK IN LATE TONIGHT THROUGH THE MORNING MONDAY.
FRONTAL BOUNDARY AT 05Z STRETCHES FROM NEAR PNT NNE TO NEAR VPZ AND
IS PROGGED LIFT NORTH INTO CHICAGO LATE TONIGHT INTO EARLY THURSDAY.
WINDS SHOULD LIGHTEN UP A BIT AS THE FRONTAL TROUGH NEARS. LOOKS
LIKE ORD IS A GOOD BET TO STAY NORTH OF THE FRONT WITH NORTHEAST
WINDS WHILE EXPECT GYY TO HAVE FROPA WITH WINDS TURNING SOUTHERLY.
IT WILL BE VERY CLOSE TO MDW BETWEEN ROUGHTLY 08-12Z BEFORE THE
BOUNDARY STARTS TO MOVE SOUTH AGAIN. THIS MEANS A HIGH DEGREE OF
UNCERTAINTY IN WIND DIRECTION FOR MDW...THOUGH WOULD EXPECT SPEEDS
TO BE LESS THAN 10 KT.
LOW PRESSURE WILL PASS NEAR OR SOUTH OF THE TERMINALS MIDDAY
THURSDAY WITH WINDS BACKING TO THE NORTH AND EVENTUALLY NORTHWEST
LATE AFTERNOON INTO THE EVENING. COOLER AIR WILL WORK INTO THE
REGION BEHIND THE LOW WITH PRECIP TYPE BECOMING MORE OF A CONCERN AS
THE DAY WEARS ON. RFD HAS THE BEST CHANCE TO SEE SOME LIGHT
ACCUMULATIONS FROM MID AFTERNOON INTO EARLY EVENING BEFORE DRIER AIR
FINALLY ARRIVES. FOR THE CHICAGO AREA...THERMAL PROFILES ARE MORE
MARGINAL AND MAY ONLY SEE A RAIN/SNOW MIX BEFORE DRIER AIR MOVES IN
AND WE LOSE ICE CRYSTALS IN THE COLUMN.
BMD
&&
.MARINE...
258 PM CDT
FRONTAL BOUNDARY DRAPED JUST SOUTH OF LAKE MICHIGAN WILL ALLOW FOR
CONTINUED BRISK NORTHEAST WINDS WHICH ALLOW FOR HIGHER WAVE ACTION
ON THE WEST HALF OF THE LAKE THROUGH TONIGHT. GALES
CONTINUE IN THE NORTHEAST REGIME FOR THE NORTHERN
MAJORITY OF THE LAKE TONIGHT. PRECIPITATION TRENDS
WILL BE ON THE INCREASE TONIGHT AS LOW PRESSURE NEARS FROM THE
SOUTHWEST. A SLIGHT INCREASE IN THE PRESSURE GRADIENT FOR THE
SOUTHERN THIRD OF THE LAKE WILL ALLOW WINDS TO INCREASE TO GALE
FORCE THURSDAY AFTERNOON. BY FRIDAY MORNING WINDS WILL RELAX AND
BECOME NORTHWEST...TRANSITIONING TO SOUTH AS HIGH PRESSURE NUDGES
IN.
MM
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ741 UNTIL 4 AM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...4 PM THURSDAY TO 4 AM FRIDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 PM THURSDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1140 PM CDT WED MAR 23 2016
.UPDATE...
Issued at 905 PM CDT Wed Mar 23 2016
The frontal boundary is extending across our northern counties,
has stalled out along a line from just south of Peoria to just
north of Bloomington. Steady northeast winds north of the front
are keeping cooler conditions there in the upper 40s, with
southerly winds south of the boundary keeping temps in the 60s.
Radar returns in east-central Illinois may be producing a few
sprinkles, but no measurable rain is expected from that band as it
mainly works to saturate the lower levels. Low pressure is still
expected to track east along the warm front, reaching near
Schuyler county around 15z/10am tomorrow. Then the low will
quickly track east across our northern counties and into Indiana
by 18z/1pm. The low will drag a cold front across our forecast
area in the process, with storms affecting our east-southeast
counties later Thursday morning into early afternoon, or mainly SE
of Effingham to Paris.
Instability params show some hail and wind potential with the
initial wave of storms that will reach Knox county around
05z/midnight, and clip northern Peoria county as well as Stark and
Marshall counties. Then the best instability looks to redevelop in
our E-SE counties Thur morning, but only marginal chances of
severe wind and hail are expected in that area as well.
Updates this evening were mainly to the weather grids to delay the
onset of rain and storms this evening, with better chances coming
after midnight. Temps are on track, with little change or diurnal
swings expected. Thus, a very mild night is in store south of the
front.
Updated forecast info is already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 258 PM CDT Wed Mar 23 2016
Frontal boundary position has not changed much since this morning,
with 2 pm analysis showing it extending from just north of Macomb,
to the northern Peoria metro area, to just south of Kankakee. Still
seeing temperatures only around 50 degrees at Galesburg, while the
Peoria airport (south side of metro) is 61 degrees. Further south,
mid-upper 60s were more widespread, with some 70 degree readings
toward Jacksonville. Radar mosaics show precipitation with this
system well off to our north.
The boundary extends southwest to a low pressure area in north
central Kansas. The low will slowly ride northeast along it, and
should nudge the front back north with time later tonight. HRRR
projecting convective development near the Missouri/Kansas border by
late afternoon, tracking it northeast to west central Illinois by
midnight. High-res models such as the ARW and NMM bring the line
into the central Illinois area after midnight. Best chances of any
strong/severe storms would basically be from I-55 west, where the
RAP model focuses MUCAPE values up to 1000 J/kg, but the incoming
line should get more disorganized with time so am not expecting a
widespread severe threat. Latest Day1 outlook has the entire
forecast area in a marginal risk of severe weather. More showers and
storms will surge northeast after midnight ahead of the incoming
cold front, with the highest PoP`s for eastern Illinois associated
with this surge.
Little in the way of temperature movement expected overnight, with
upper 50s to lower 60s prevailing much of the time. Biggest question
mark remains with the far north, depending on the position of the
front.
.LONG TERM...(Thursday through Wednesday)
ISSUED AT 258 PM CDT Wed Mar 23 2016
12Z forecast models generally bring 991 mb low pressure over
north central KS to track along a frontal boundary into northeast IL
by midday Thu as it weakens to 995-998 mb and swing a cold front
east across IL roughly between 15Z-21Z. High chances of showers and
a few thunderstorms early Thu morning to gradually diminish chances
from west to east during afternoon behind cold front. A new line of
convection to develop ahead of cold front during Thu afternoon and
SPC has marginal risk of severe near the Wabash river valley Thu
afternoon for hail and gusty winds, though best chances of stronger
storms will be further east of IN. Not much temp rise Thu with
breezy conditions again and may even slip behind the cold frontal
passage, with highs ranging from 50-55F nw of IL river to 60-65F
over eastern IL. Snow chances still appears to be north of CWA on
Thu and only have slight chances of light rain/snow showers Thu
evening over east central IL with no accumulations.
Low pressure moves into the eastern Great Lakes region overnight Thu
night and winds to gradually diminish as weak high pressure of 1020
mb settles east into the MS river valley by dawn Friday. Low clouds
to decrease from west to east overnight Thu night and set up another
night of freezing temps over central and nw IL. Lows 27-32F with
areas se of I-70 32-34F. Southern 6 counties where growing season
has begun, may need a freezing warning especially if clouds and
winds diminish quicker overnight Thu night. Weak high pressure
drifts east over IL Fri morning and into Ohio by sunset Friday,
providing a mostly sunny day with lighter winds, and highs mostly in
the lower 50s. So a similar day on Friday that we experienced this
past Monday.
A short wave trof off the Canadian Pacific coast will dive southeast
and deepen an upper level trof into the Rockies and great plains
this Easter Weekend. This ejects another fairly strong low pressure
ne from north Texas at sunset Saturday into central or southeast IL
on Easter Sunday. 12Z models still have some timing differences
along with placement of low pressure track and will stay close to
consensus. Have chances of showers into areas form I-55 west by
Saturday afternoon as clouds increase, with milder highs in the
upper 50s/lower 60s. Shower chances then spreading east over rest of
CWA Sat night, except still dry in far southeast IL near Wabash
river until Sunday. Depending on track of low pressure, southeast IL
may see a few thunderstorms on Easter Sunday. Highs Sunday range
from lower 50s nw of IL river, to 60-65F in southeast IL. Shower
chances to diminish from west to east overnight Sunday night and may
linger isolated showers near Wabash river Monday morning. High
pressure ridge already moving into IL by Monday afternoon to
decrease clouds on Monday with seasonable highs in the mid 50s.
Upper level ridging into the MS river valley on Tue and ohio river
valley next Wed to bring quiet weather with temps moderating to 55-
60F on Tue and into the 60s next Wed. Next chance of showers and
possible thunderstorms to arrive middle of next week on Wed night
and Thu as low pressure tracks into the upper MS river valley.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1140 PM CDT Wed Mar 23 2016
Frontal boundary has remained stationary from just south of PIA
to just north of BMI this evening. Winds at PIA remained E, with S
winds at the remaining terminals. As low pressure continues to
approach from the west, winds will eventually shift veer to SW by
mid-day and then become W-NW from late afternoon near PIA to mid-
evening at CMI.
A line of storms approaching Knox county appears to be tracking to
the NW of Peoria. Showers are on track to affect the PIA airport
between 0530z and 07z before lifting off to the northeast. After
that, the HRRR and RAP models point toward the development of a
line of showers and storms along the Illinois River Valley around
10z/5am. The line is expected to expand eastward, then with the
back edge of rain lingering near the IL river until the low
pressure center reaches PIA around 17z and progresses into Indiana
by 20z. A trough of low pressure trailing behind the low along
I-74 will be the focus for light rain showers through the
afternoon for the northern terminals of PIA and BMI. The other
terminals will see precip come to an end from west to east between
19z at SPI to 21z at CMI. If any precip continues near PIA to BMI
until 00z/7pm, light snow could develop. However, no snow
accumulation is expected.
The aviation conditions will dip from VFR to MVFR as precipitation
develops, then remain MVFR possibly until the end of the taf
period. The southern terminals will have the better potential of
seeing cigs improve to VFR during the afternoon as the dry slot
punches across SPI/DEC/CMI. Then, wrap around moisture and a
subsidence inversion could produce MVFR clouds again at all TAF
sites after sunset tomorrow evening.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Shimon
SHORT TERM...Geelhart
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
229 PM EDT THU MAR 24 2016
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY|/...
ISSUED AT 955 AM EDT THU MAR 24 2016
1345Z UPDATE...CHANGES WERE MADE TO REFLECT THE CURRENT RADAR
MOSAIC WHICH SHOWERS A LITTLE FARTHER WIDESPREAD AND OVER MOST OF
THE FORECAST AREA AS OF THIS HOUR. CONVECTION IS LAGGING
BEHIND...HOWEVER CHANCES WILL REMAIN IN THE FORECAST FOR THIS
AFTERNOON BEFORE AND WHILE THE FRONT MOVES THROUGH THE AREA BY
LATE THIS AFTERNOON. STILL KEEPING 90/100 PERCENT POPS OVER THE
MAJORITY OF THE AREA. SOME MINOR TWEAKS WERE MADE TO HIGH
TEMPERATURES TODAY AS MANY OF THE SITE PROBABLY ALREADY HIT THEIR
HIGH TEMPERATURE MARK EARLIER THIS MORNING AND WILL REMAIN STEADY
OR DECLINE. SITES TO THE NORTHWEST SUCH AS LAF...WHICH MAY SEE
SOME CLEARING LATE THIS AFTERNOON BEHIND THE PRECIP COULD SEE
TEMPERATURE BRIEFLY REBOUND HERE INTO THE LOW 60S. SO LEFT
TEMPERATURE FORECAST AS IS FOR THIS AREA RIGHT NOW. OTHERWISE NO
OTHER MAJOR UPDATES WERE NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS...
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 220 PM EDT THU MAR 24 2016
LONG TERM MODELS SHOW SOME DISAGREEMENT EARLY IN THE LONG TERM ON
TIMING AND STRENGTH OF AN UPPER WAVE AND ASSOCIATED FRONTAL
SYSTEM. THE GFS IS WEAKER AND FASTER WITH THIS FEATURE WHILE THE
ECMWF IS SLOWER AND STRONGER...HOLDING ONTO RAIN OVER THE AREA
INTO MONDAY. INITIALIZATION HELD ONTO LIKELY POPS FOR SUNDAY NIGHT
AND CARRIED CHANCES INTO MONDAY AND THOUGHT THIS WAS A GOOD
COMPROMISE WITH A NUDGE TOWARD THE ECMWF WHICH HAS HAD BETTER
CONSISTENCY WITH THIS FEATURE. BY MONDAY NIGHT THOUGH BOTH MODELS
LINE UP AGAIN WITH RIDGING OVER THE AREA AND DRY WEATHER IN PLACE
THROUGH THE DAY ON WEDNESDAY. MONDAY NIGHT CURRENTLY
INITIALIZATION LOW TEMPERATURES ARE ABOVE FREEZING BUT THIS MAY
NEED TO BE MONITORED FOR FROST/FREEZE POTENTIAL AS WE GET CLOSER.
HIGHS LOOK LIKE THEY/LL WARM BACK INTO THE 60S FOR WEDNESDAY AND
THURSDAY AHEAD OF A FRONTAL SYSTEM THAT COULD MOVE IN TO THE AREA
BRINGING RAIN CHANCES WITH IT FOR WEDNESDAY NIGHT ON. WITH LESS
CERTAINTY ON TIMING OF MID/END OF WEEK FRONTAL SYSTEM DECREASED
INITIALIZATION POPS FROM LIKELY TO CHANCE.
&&
.AVIATION /DISCUSSION FOR 241800Z TAF ISSUANCE/...
ISSUED AT 110 PM EDT THU MAR 24 2016
SITES WILL HAVE VARIABLE CEILINGS OVER THE NEXT FEW HOURS AS SOME
SHOWERS WITH EMBEDDED THUNDERSTORMS MOVE THROUGH AND THEN POSSIBLE
BREAK FOLLOWED BY A LINE OF SHOWERS AND STORMS PASSING AHEAD OF A
COLD FRONT. EXPECT TO SEE BOUNCING AROUND FROM VFR TO MVFR AND IFR
WITHIN SHOWERS FROM NOW UNTIL FRONTAL PASSAGE AROUND 20-23Z. THIS
LINE COULD BRING WITH IT SOME STRONGER WIND GUSTS AND HAVE
INCLUDED THESE IN A TEMPO GROUP. AFTER THE FRONT PASSES EXPECT TO
SEE CEILINGS RISE FOR A FEW HOURS BEFORE DROPPING BACK TO MVFR AND
THEN LOW END MVFR DURING THE OVERNIGHT. WIND GUSTS COULD PICK UP
IN THE DRY SLOT AROUND THE FRONT BUT THEN SHOULD DECREASE IN SPEED
TONIGHT. SOUNDINGS INDICATE GUSTS WILL CONTINUE THROUGH THE NIGHT
THOUGH AS LOW PRESSURE PULLS AWAY BUT WILL DROP TO AROUND 18-22
KTS AND DROP OFF COMPLETELY BETWEEN 12-15Z FRIDAY AS HIGH PRESSURE
BUILDS IN.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....CP
AVIATION...CP
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
208 PM EDT THU MAR 24 2016
.SYNOPSIS...
ISSUED AT 200 PM EDT THU MAR 24 2016
A DISTURBANCE WILL INTERACT WITH A FRONTAL BOUNDARY ACROSS THE
AREA TO PRODUCE WIDESPREAD RAIN SHOWERS ALONG WITH A FEW
THUNDERSTORMS THROUGH THIS AFTERNOON. GUSTY SOUTH WINDS ARE
EXPECTED IN ADVANCE OF THE COLD FRONT WITH THIS SYSTEM...
PARTICULARLY ACROSS FAR NORTHEAST INDIANA AND NORTHWEST OHIO
TODAY. CLOUDS WILL DIMINISH ON FRIDAY WITH COOLER TEMPERATURES.
LOW TEMPERATURES TONIGHT WILL DROP INTO THE LOWER TO MID 30S.
HIGHS ON FRIDAY WILL ONLY BE IN THE 40S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM EDT THU MAR 24 2016
STALLED SURFACE BOUNDARY REMAINS SPRAWLED FROM FAR NORTHERN INDIANA
INTO FAR NORTHWEST OHIO THIS MORNING. BROAD ISENTROPIC LIFT/MOISTURE
ADVECTION CONTINUES IN ASSOCIATION WITH THIS BOUNDARY AND HAS
LARGELY BEEN RESPONSIBLE FOR WIDESPREAD RAIN SHOWERS/DRIZZLE ACROSS
PRIMARILY NORTHERN HALF OF THE FORECAST AREA DURING THE OVERNIGHT
HOURS. EXPECTING THAT SOME DIMINISHMENT IN RAIN SHOWER COVERAGE WILL
OCCUR ACROSS THE NORTH DURING THE EARLY-MID MORNING HOURS AS MORE
FAVORED ZONE OF ISENTROPIC ASCENT PER 295K-300K LAYER PROGS LIFTS
NORTHWARD ACROSS CENTRAL LOWER MICHIGAN. RAIN POTENTIAL TO RAMP
UP FROM WEST TO EAST FROM MID MORNING THROUGH THE AFTERNOON AS
POTENT PV ANOMALY OVERSPREADS MID MS VALLEY/SOUTHERN GREAT LAKES
ALONG WITH A CORRESPONDING DOWNSTREAM LOW/MID LEVEL FGEN RESPONSE.
SOME WEAK ELEVATED INSTABILITY IS NOTED PER SPC RUC ANALYSIS AT
06Z ACROSS THE FAR NORTH...BUT PRIMARY INSTABILITY AXIS OF NOTE
FOR LOCAL AREA WILL BE IMMEDIATELY PRECEDING SFC COLD FRONTAL
BOUNDARY THIS AFTERNOON WITH SOME DIFFERENTIAL THERMAL ADVECTION
SETTING UP THIS NARROW CORRIDOR OF INSTABILITY. MAGNITUDE OF
INSTABILITY IS EXPECTING TO BE ON THE MARGINAL SIDE...GENERALLY IN
THE 500-800 J/KG RANGE...BUT A BRIEF POTENTIAL OF NEAR SFC/SFC
BASED INSTABILITY MAY EXIST ACROSS SOUTHEAST HALF OF THE AREA LATE
MORNING-LATE AFTERNOON. THIS WEAK INSTABILITY COMBINED WITH FAIRLY
IMPRESSIVE DEEP LAYER SHEAR MAGNITUDES OF 50-60 KNOTS DOES POSE
SOME CONCERN FOR SMALL LINEAR BOWING SEGMENTS. THIS THREAT REMAINS
HIGHLY CONDITIONAL ON INSTABILITY AND OVERALL SEVERE THREAT
REMAINS LOW. NOT MUCH CHANGE FROM PREVIOUS FORECAST THINKING WITH
ISOLD SEVERE POTENTIAL AT BEST TODAY GIVEN LIMITED
INSTABILITY...WITH ISOLATED STRONGER WIND GUSTS AS THE MAIN
THREAT.
TEMPERATURE FORECAST REMAINS A CHALLENGING ONE IN THE NEAR
TERM...WITH A 20 DEGREE NORTH TO SOUTH TEMPERATURE DIFFERENTIAL
ACROSS THE FORECAST AREA THIS MORNING. SFC BOUNDARY HAS REMAINED
SOMEWHAT STUBBORNLY ANCHORED ACROSS FAR NORTHERN INDIANA...BUT
SHOULD START TO SEE SOME NORTHWARD RETREAT OF THIS BOUNDARY IN THE
09Z-15Z TIMEFRAME. THIS SHOULD PUT BULK OF FORECAST AREA IN WARM
SECTOR...ALBEIT FOR A VERY BRIEF TIME ACROSS THE FAR NORTHWEST AS
SFC REFLECTION REACHES NORTHWEST INDIANA LATE MORNING. OVERALL NOT
MUCH CHANGE TO INHERITED MAX TEMPS...WITH JUST A SLIGHT UPWARD
ADJUSTMENTS INTO THE MID 60S FAR SOUTH CENTRAL/EAST WHERE RESIDENCE
TIME OF WARM SECTOR WILL BE PROLONGED...AND WHERE A MORE DELAYED
PRECIP TIMING IS ANTICIPATED. ANOTHER LOWER END CONCERN TODAY WILL
BE A BRIEF POTENTIAL OF NEAR ADVISORY OR ADVISORY LEVEL SOUTH-
SOUTHWEST WINDS AHEAD OF THIS SYSTEM. SFC REFLECTION SHOULD BE IN A
SLIGHT DEEPENING MODE THIS AFTERNOON WITH AN AXIS OF FAIRLY
STRONG SFC PRESSURE FALLS EXPECTED TO DEVELOP/MIGRATE ACROSS
SOUTHEAST LOWER MICHIGAN. THESE PRESSURE FALLS COMBINED WITH
POTENTIALLY BETTER MIXING WHERE SFC TEMPS ARE EXPECTED TO REACH
THE MID 60S...COULD ALLOW FOR A BRIEF WINDOW OF 35 TO 45 MPH WIND
GUSTS ACROSS THE FAR EAST IN THE 16Z-21Z TIMEFRAME GIVEN STRONG
LOW LEVEL WIND FIELD. HAVE HELD OFF ON ANY WIND ADVISORY AT THIS
TIME GIVEN LOW CONFIDENCE ON DEPTH OF MIXING AND RELATIVELY SHORT
DURATION OF THIS POTENTIAL.
DRY SLOT TO OVERSPREAD THE AREA TONIGHT AS COLDER AIR ADVECTS
SOUTHEASTWARD BEHIND THE FRONT DIMINISHING PRECIP COVERAGE IN THE
EVENING...ALTHOUGH DEFORMATION ZONE MAY PROLONG AT LEAST SCATTERED
SHOWERS ACROSS THE FAR NORTHWEST. ANY CHANGEOVER TO SNOW SHOULD BE
OF MINIMAL PRECIP COVERAGE/INTENSITY AND NO SNOW ACCUMULATION IS
ANTICIPATED AT THIS TIME. END OF THIS PRECIP EVENT COULD TURN OUT
TO BE MORE DRIZZLY IN NATURE TONIGHT...BUT CURRENTLY NOT EXPECTING
ANY SIGNIFICANT IMPACTS FROM POTENTIAL DRIZZLE OR FREEZING DRIZZLE
TONIGHT.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 342 AM EDT THU MAR 24 2016
MUCH MORE BENIGN WEATHER ANTICIPATED FOR FRIDAY AND SATURDAY. ANY
RESIDUAL RN/SN SHOWERS WILL BE QUICKLY CUT OFF BY 12Z AS SHORTWAVE
RIDGE AND ASSOCIATED BUBBLE OF SUBSIDENCE/SURFACE HIGH PRESSURE FOLD
INTO THE GREAT LAKES. SHOULD BE MOSTLY SUNNY BY AFTERNOON AS
NEGATIVE THETA-E ADVECTION FINALLY ERODES THIN LAYER OF MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION IN CAA REGIME. HIGH TEMPS WILL
MAKE A RUN AT UPPER 40S BY LATE AFTERNOON AS WINDS START TO BACK.
LOW 50S MAY EVEN BE POSSIBLE IF MORNING CLOUDS DISSIPATE QUICKER
THAN EXPECTED. MUCH WARMER CONDITIONS FOR SATURDAY AS SW FLOW/WAA
RAMP UP AHEAD OF NEXT WAVE. UPPER 50S TO NEAR 60F POSSIBLE GIVEN
850MB TEMPS AROUND 4C...BUT THE TRADEOFF WILL BE INCREASING HIGH-
BASED CLOUDS ESPECIALLY IN OUR NORTHWEST BY AFTERNOON AS MIDLEVEL
WARM/MOIST AIR ADVECTION INCREASES.
NEXT CHANCE OF RAIN WILL ARRIVE EARLY SUNDAY MORNING AS ANOTHER
VIGOROUS SHORTWAVE RIPPLES THROUGH THE REGION. STILL SOME
INCONSISTENCIES AMONG THE LATEST DETERMINISTIC GUIDANCE TO WORK OUT.
HOWEVER DOES APPEAR TO BE SOME CONSENSUS FOR SURFACE WAVE
DEVELOPMENT ALONG BAROCLINIC ZONE WITH DECENT SHOT OF SOME MODERATE
RAIN AS MIDLEVEL TROUGH TAKES ON AT LEAST A NEUTRAL TILT. BEST
PRECIP CHANCES LOOK TO BE SUNDAY AFTERNOON INTO SUNDAY NIGHT.
THERMAL PROFILES SHOULD BE WARM ENOUGH FOR ALL RAIN...THOUGH IT IS
WORTH NOTING THE ECMWF SOLUTION WOULD SUPPORT THE POSSIBILITY OF A
FEW WET SNOWFLAKES MIXING IN ON BACK EDGE OF EXITING DEFORMATION
BAND. STILL PLENTY OF TIME TO WATCH THIS EVENT AND SUSPECT THERE
WILL BE CHANGES SINCE PARENT JET ENERGY IS STILL OVER THE NORTH
PACIFIC. QUIET WEATHER THEREAFTER AS SPRAWLING MID/UPPER RIDGE AND
SURFACE HIGH MOVE OVER THE REGION. COOL AT FIRST BUT SHOULD WARM UP
AGAIN BY MIDWEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 202 PM EDT THU MAR 24 2016
TIMING OF LACKLUSTER CONVECTION INTO KSBN IN 20-22 UTC WINDOW.
LESS CERTAINTY OF CONVECTION HOLDING TOGETHER THROUGH THE LATER
EVENING HOURS DUE TO LACK OF SIGNIFICANT DOWNSTREAM
DESTABILIZATION. BEST CHC FOR IFR CIGS AT KSBN AS WELL IN CLOSER
PROXIMITIY TO DEEP WRAPPED MOISTURE NW OF SURFACE LOW TRACK.
OTHERWISE LONG DURATION FUELING/ALTERNATE CRITIERA FOR NORTHERN
INDIANA...TURNING DECIDEDLY VFR TOWARD END OF FORECAST PD AS DRY
AIR ADVECTION AND SUBSIDENCE BRING AT LEAST PARTIAL
CLEARING/SCATTER OUT OF STRATOCU DECK.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING FROM 8 PM THIS EVENING TO 5 AM EDT FRIDAY FOR
LMZ043-046.
&&
$$
SYNOPSIS...MURPHY
SHORT TERM...MARSILI
LONG TERM...AGD
AVIATION...MURPHY
VISIT US AT WW.WEATHER.GOV/IWX
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
117 PM EDT THU MAR 24 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY|/...
ISSUED AT 955 AM EDT THU MAR 24 2016
1345Z UPDATE...CHANGES WERE MADE TO REFLECT THE CURRENT RADAR
MOSAIC WHICH SHOWERS A LITTLE FARTHER WIDESPREAD AND OVER MOST OF
THE FORECAST AREA AS OF THIS HOUR. CONVECTION IS LAGGING
BEHIND...HOWEVER CHANCES WILL REMAIN IN THE FORECAST FOR THIS
AFTERNOON BEFORE AND WHILE THE FRONT MOVES THROUGH THE AREA BY
LATE THIS AFTERNOON. STILL KEEPING 90/100 PERCENT POPS OVER THE
MAJORITY OF THE AREA. SOME MINOR TWEAKS WERE MADE TO HIGH
TEMPERATURES TODAY AS MANY OF THE SITE PROBABLY ALREADY HIT THEIR
HIGH TEMPERATURE MARK EARLIER THIS MORNING AND WILL REMAIN STEADY
OR DECLINE. SITES TO THE NORTHWEST SUCH AS LAF...WHICH MAY SEE
SOME CLEARING LATE THIS AFTERNOON BEHIND THE PRECIP COULD SEE
TEMPERATURE BRIEFLY REBOUND HERE INTO THE LOW 60S. SO LEFT
TEMPERATURE FORECAST AS IS FOR THIS AREA RIGHT NOW. OTHERWISE NO
OTHER MAJOR UPDATES WERE NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS...
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR 241800Z TAF ISSUANCE/...
ISSUED AT 110 PM EDT THU MAR 24 2016
SITES WILL HAVE VARIABLE CEILINGS OVER THE NEXT FEW HOURS AS SOME
SHOWERS WITH EMBEDDED THUNDERSTORMS MOVE THROUGH AND THEN POSSIBLE
BREAK FOLLOWED BY A LINE OF SHOWERS AND STORMS PASSING AHEAD OF A
COLD FRONT. EXPECT TO SEE BOUNCING AROUND FROM VFR TO MVFR AND IFR
WITHIN SHOWERS FROM NOW UNTIL FRONTAL PASSAGE AROUND 20-23Z. THIS
LINE COULD BRING WITH IT SOME STRONGER WIND GUSTS AND HAVE
INCLUDED THESE IN A TEMPO GROUP. AFTER THE FRONT PASSES EXPECT TO
SEE CEILINGS RISE FOR A FEW HOURS BEFORE DROPPING BACK TO MVFR AND
THEN LOW END MVFR DURING THE OVERNIGHT. WIND GUSTS COULD PICK UP
IN THE DRY SLOT AROUND THE FRONT BUT THEN SHOULD DECREASE IN SPEED
TONIGHT. SOUNDINGS INDICATE GUSTS WILL CONTINUE THROUGH THE NIGHT
THOUGH AS LOW PRESSURE PULLS AWAY BUT WILL DROP TO AROUND 18-22
KTS AND DROP OFF COMPLETELY BETWEEN 12-15Z FRIDAY AS HIGH PRESSURE
BUILDS IN.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...CP
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1045 AM EDT THU MAR 24 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY|/...
ISSUED AT 955 AM EDT THU MAR 24 2016
1345Z UPDATE...CHANGES WERE MADE TO REFLECT THE CURRENT RADAR
MOSAIC WHICH SHOWERS A LITTLE FARTHER WIDESPREAD AND OVER MOST OF
THE FORECAST AREA AS OF THIS HOUR. CONVECTION IS LAGGING
BEHIND...HOWEVER CHANCES WILL REMAIN IN THE FORECAST FOR THIS
AFTERNOON BEFORE AND WHILE THE FRONT MOVES THROUGH THE AREA BY
LATE THIS AFTERNOON. STILL KEEPING 90/100 PERCENT POPS OVER THE
MAJORITY OF THE AREA. SOME MINOR TWEAKS WERE MADE TO HIGH
TEMPERATURES TODAY AS MANY OF THE SITE PROBABLY ALREADY HIT THEIR
HIGH TEMPERATURE MARK EARLIER THIS MORNING AND WILL REMAIN STEADY
OR DECLINE. SITES TO THE NORTHWEST SUCH AS LAF...WHICH MAY SEE
SOME CLEARING LATE THIS AFTERNOON BEHIND THE PRECIP COULD SEE
TEMPERATURE BRIEFLY REBOUND HERE INTO THE LOW 60S. SO LEFT
TEMPERATURE FORECAST AS IS FOR THIS AREA RIGHT NOW. OTHERWISE NO
OTHER MAJOR UPDATES WERE NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS...
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 241500Z TAFS/...
ISSUED AT 1045 AM EDT THU MAR 24 2016
RADAR LOOP AT 1030 AM SHOWS RAIN OVER ALL THE SITES. SOME EMBEDDED
LIGHTNING STRIKES HAVE ALREADY BEEN SEEN IN PARTS OF CENTRAL INDIANA
BUT HAVEN/T HAD LIGHTNING AT ANY OF THE TERMINALS YET. LOOKING
UPSTREAM SEE MORE CONVECTIVE CELLS FORMING IN CENTRAL ILLINOIS IN
THE DRY SLOT AREA MENTIONED BELOW...SO OVERALL FORECAST THINKING
FROM EARLIER IS STILL ON TRACK. FOR THE UPDATE TWEAKED TIMING OF
THUNDER SLIGHTLY AT A COUPLE SITES TO BETTER MATCH HI RES MODELS AND
MADE SOME ADJUSTMENTS TO WINDS WITH STRONG GUSTS OCCURRING QUICKER
AT KBMG BUT BEING LOWER AT OTHER SITES FOR ANOTHER HOUR OR TWO.
DECENT POTENTIAL FOR EMBEDDED LIGHTNING STRIKES TOWARDS MIDDAY INTO
THE AFTERNOON...NEAR THE LEADING EDGE OF THE DRY SLOT AND SURFACE
COLD FRONT AS MID LEVEL LAPSE RATES STEEPEN. BEST POTENTIAL FOR IFR
VISIBILITY RESTRICTIONS APPEAR TO BE IN THIS REGION AS WELL.
PRECIPITATION WILL END BY LATE AFTERNOON WITH THE ARRIVAL OF THE DRY
SLOT.
CEILINGS ARE GRADUALLY LOWERING INTO THE 015-025 RANGE. BRIEFLY
LOWER CEILINGS POSSIBLE IN HEAVIER PRECIPITATION CELLS. CEILINGS
WILL PROBABLY LIFT FOR A TIME LATE THIS AFTERNOON UNDER THE DRY SLOT.
SHOULD SEE SURFACE WIND GUSTS APPROACHING 30 KTS FROM 180-200 DEGREES BY LATE
MORNING AS A 55-60 LOW LEVEL JET CORE MOVES OVERHEAD. WINDS EXPECTED TO VEER
AROUND TO 230-250 DEGREES BY LATE AFTERNOON AFTER FRONTAL PASSAGE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS/CP
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1008 AM EDT THU MAR 24 2016
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY|/...
ISSUED AT 955 AM EDT THU MAR 24 2016
1345Z UPDATE...CHANGES WERE MADE TO REFLECT THE CURRENT RADAR
MOSAIC WHICH SHOWERS A LITTLE FARTHER WIDESPREAD AND OVER MOST OF
THE FORECAST AREA AS OF THIS HOUR. CONVECTION IS LAGGING
BEHIND...HOWEVER CHANCES WILL REMAIN IN THE FORECAST FOR THIS
AFTERNOON BEFORE AND WHILE THE FRONT MOVES THROUGH THE AREA BY
LATE THIS AFTERNOON. STILL KEEPING 90/100 PERCENT POPS OVER THE
MAJORITY OF THE AREA. SOME MINOR TWEAKS WERE MADE TO HIGH
TEMPERATURES TODAY AS MANY OF THE SITE PROBABLY ALREADY HIT THEIR
HIGH TEMPERATURE MARK EARLIER THIS MORNING AND WILL REMAIN STEADY
OR DECLINE. SITES TO THE NORTHWEST SUCH AS LAF...WHICH MAY SEE
SOME CLEARING LATE THIS AFTERNOON BEHIND THE PRECIP COULD SEE
TEMPERATURE BRIEFLY REBOUND HERE INTO THE LOW 60S. SO LEFT
TEMPERATURE FORECAST AS IS FOR THIS AREA RIGHT NOW. OTHERWISE NO
OTHER MAJOR UPDATES WERE NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS...
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 241200Z TAFS/...
ISSUED AT 638 AM EDT THU MAR 24 2016
SOME SHOWER ACTIVITY OVER WEST CENTRAL AND SOUTHWEST INDIANA MAY IMPACT THE
TERMINALS EARLY THIS MORNING. HOWEVER...SHORT TERM MODEL GUIDANCE SUGGESTS
THE MAIN LIFT/MORE WIDESPREAD SHOWER ACTIVITY PROBABLY WON/T MOVE INTO THE
AREA UNTIL THE MID TO LATE MORNING HOURS...ROUGHLY AFTER 241400Z. DECENT
POTENTIAL FOR EMBEDDED LIGHTNING STRIKES TOWARDS MIDDAY INTO THE
AFTERNOON...NEAR THE LEADING EDGE OF THE DRY SLOT AND SURFACE COLD FRONT AS
MID LEVEL LAPSE RATES STEEPEN. BEST POTENTIAL FOR IFR VISIBILITY RESTRICTIONS
APPEAR TO BE IN THIS REGION AS WELL. PRECIPITATION WILL END BY LATE AFTERNOON
WITH THE ARRIVAL OF THE DRY SLOT.
CEILINGS 040-050 EARLY THIS MORNING WILL GRADUALLY LOWER INTO THE 020-025 RANGE
AS THE MAIN PRECIPITATION AREA ARRIVES. BRIEFLY LOWER CEILINGS POSSIBLE IN
HEAVIER PRECIPITATION CELLS. CEILINGS WILL PROBABLY LIFT FOR A TIME LATE THIS
AFTERNOON UNDER THE DRY SLOT.
SHOULD SEE SURFACE WIND GUSTS APPROACHING 30 KTS FROM 180-200 DEGREES BY LATE
MORNING AS A 55-60 LOW LEVEL JET CORE MOVES OVERHEAD. WINDS EXPECTED TO VEER
AROUND TO 230-250 DEGREES BY LATE AFTERNOON AFTER FRONTAL PASSAGE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
657 AM EDT THU MAR 24 2016
.SYNOPSIS...
ISSUED AT 342 AM EDT THU MAR 24 2016
AN UPPER LEVEL DISTURBANCE ACROSS THE CENTRAL UNITED STATES WILL
APPROACH THE AREA TODAY. THIS DISTURBANCE WILL INTERACT WITH A
FRONTAL BOUNDARY ACROSS THE AREA TO PRODUCE WIDESPREAD RAIN
SHOWERS ALONG WITH A FEW THUNDERSTORMS THROUGH THIS AFTERNOON.
GUSTY SOUTH WINDS ARE EXPECTED IN ADVANCE OF THE COLD FRONT WITH
THIS SYSTEM...PARTICULARLY ACROSS FAR NORTHEAST INDIANA AND
NORTHWEST OHIO TODAY. SCATTERED RAIN SHOWERS MAY LINGER INTO THIS
EVENING...BUT DRIER AND COOLER AIR MOVING INTO THE REGION BEHIND A
COLD FRONT WILL GRADUALLY END THE CHANCES OF ADDITIONAL RAIN
SHOWERS OVERNIGHT. CLOUDS WILL DIMINISH ON FRIDAY WITH COOLER
TEMPERATURES. HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE
MID 50S ACROSS NORTHWEST INDIANA AND FAR SOUTHWEST LOWER
MICHIGAN...TO THE MID 60S ACROSS NORTHWEST OHIO. LOW TEMPERATURES
TONIGHT WILL DROP INTO THE LOWER TO MID 30S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM EDT THU MAR 24 2016
STALLED SURFACE BOUNDARY REMAINS SPRAWLED FROM FAR NORTHERN INDIANA
INTO FAR NORTHWEST OHIO THIS MORNING. BROAD ISENTROPIC LIFT/MOISTURE
ADVECTION CONTINUES IN ASSOCIATION WITH THIS BOUNDARY AND HAS
LARGELY BEEN RESPONSIBLE FOR WIDESPREAD RAIN SHOWERS/DRIZZLE ACROSS
PRIMARILY NORTHERN HALF OF THE FORECAST AREA DURING THE OVERNIGHT
HOURS. EXPECTING THAT SOME DIMINISHMENT IN RAIN SHOWER COVERAGE WILL
OCCUR ACROSS THE NORTH DURING THE EARLY-MID MORNING HOURS AS MORE
FAVORED ZONE OF ISENTROPIC ASCENT PER 295K-300K LAYER PROGS LIFTS
NORTHWARD ACROSS CENTRAL LOWER MICHIGAN. RAIN POTENTIAL TO RAMP
UP FROM WEST TO EAST FROM MID MORNING THROUGH THE AFTERNOON AS
POTENT PV ANOMALY OVERSPREADS MID MS VALLEY/SOUTHERN GREAT LAKES
ALONG WITH A CORRESPONDING DOWNSTREAM LOW/MID LEVEL FGEN RESPONSE.
SOME WEAK ELEVATED INSTABILITY IS NOTED PER SPC RUC ANALYSIS AT
06Z ACROSS THE FAR NORTH...BUT PRIMARY INSTABILITY AXIS OF NOTE
FOR LOCAL AREA WILL BE IMMEDIATELY PRECEDING SFC COLD FRONTAL
BOUNDARY THIS AFTERNOON WITH SOME DIFFERENTIAL THERMAL ADVECTION
SETTING UP THIS NARROW CORRIDOR OF INSTABILITY. MAGNITUDE OF
INSTABILITY IS EXPECTING TO BE ON THE MARGINAL SIDE...GENERALLY IN
THE 500-800 J/KG RANGE...BUT A BRIEF POTENTIAL OF NEAR SFC/SFC
BASED INSTABILITY MAY EXIST ACROSS SOUTHEAST HALF OF THE AREA LATE
MORNING-LATE AFTERNOON. THIS WEAK INSTABILITY COMBINED WITH FAIRLY
IMPRESSIVE DEEP LAYER SHEAR MAGNITUDES OF 50-60 KNOTS DOES POSE
SOME CONCERN FOR SMALL LINEAR BOWING SEGMENTS. THIS THREAT REMAINS
HIGHLY CONDITIONAL ON INSTABILITY AND OVERALL SEVERE THREAT
REMAINS LOW. NOT MUCH CHANGE FROM PREVIOUS FORECAST THINKING WITH
ISOLD SEVERE POTENTIAL AT BEST TODAY GIVEN LIMITED
INSTABILITY...WITH ISOLATED STRONGER WIND GUSTS AS THE MAIN
THREAT.
TEMPERATURE FORECAST REMAINS A CHALLENGING ONE IN THE NEAR
TERM...WITH A 20 DEGREE NORTH TO SOUTH TEMPERATURE DIFFERENTIAL
ACROSS THE FORECAST AREA THIS MORNING. SFC BOUNDARY HAS REMAINED
SOMEWHAT STUBBORNLY ANCHORED ACROSS FAR NORTHERN INDIANA...BUT
SHOULD START TO SEE SOME NORTHWARD RETREAT OF THIS BOUNDARY IN THE
09Z-15Z TIMEFRAME. THIS SHOULD PUT BULK OF FORECAST AREA IN WARM
SECTOR...ALBEIT FOR A VERY BRIEF TIME ACROSS THE FAR NORTHWEST AS
SFC REFLECTION REACHES NORTHWEST INDIANA LATE MORNING. OVERALL NOT
MUCH CHANGE TO INHERITED MAX TEMPS...WITH JUST A SLIGHT UPWARD
ADJUSTMENTS INTO THE MID 60S FAR SOUTH CENTRAL/EAST WHERE RESIDENCE
TIME OF WARM SECTOR WILL BE PROLONGED...AND WHERE A MORE DELAYED
PRECIP TIMING IS ANTICIPATED. ANOTHER LOWER END CONCERN TODAY WILL
BE A BRIEF POTENTIAL OF NEAR ADVISORY OR ADVISORY LEVEL SOUTH-
SOUTHWEST WINDS AHEAD OF THIS SYSTEM. SFC REFLECTION SHOULD BE IN A
SLIGHT DEEPENING MODE THIS AFTERNOON WITH AN AXIS OF FAIRLY
STRONG SFC PRESSURE FALLS EXPECTED TO DEVELOP/MIGRATE ACROSS
SOUTHEAST LOWER MICHIGAN. THESE PRESSURE FALLS COMBINED WITH
POTENTIALLY BETTER MIXING WHERE SFC TEMPS ARE EXPECTED TO REACH
THE MID 60S...COULD ALLOW FOR A BRIEF WINDOW OF 35 TO 45 MPH WIND
GUSTS ACROSS THE FAR EAST IN THE 16Z-21Z TIMEFRAME GIVEN STRONG
LOW LEVEL WIND FIELD. HAVE HELD OFF ON ANY WIND ADVISORY AT THIS
TIME GIVEN LOW CONFIDENCE ON DEPTH OF MIXING AND RELATIVELY SHORT
DURATION OF THIS POTENTIAL.
DRY SLOT TO OVERSPREAD THE AREA TONIGHT AS COLDER AIR ADVECTS
SOUTHEASTWARD BEHIND THE FRONT DIMINISHING PRECIP COVERAGE IN THE
EVENING...ALTHOUGH DEFORMATION ZONE MAY PROLONG AT LEAST SCATTERED
SHOWERS ACROSS THE FAR NORTHWEST. ANY CHANGEOVER TO SNOW SHOULD BE
OF MINIMAL PRECIP COVERAGE/INTENSITY AND NO SNOW ACCUMULATION IS
ANTICIPATED AT THIS TIME. END OF THIS PRECIP EVENT COULD TURN OUT
TO BE MORE DRIZZLY IN NATURE TONIGHT...BUT CURRENTLY NOT EXPECTING
ANY SIGNIFICANT IMPACTS FROM POTENTIAL DRIZZLE OR FREEZING DRIZZLE
TONIGHT.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 342 AM EDT THU MAR 24 2016
MUCH MORE BENIGN WEATHER ANTICIPATED FOR FRIDAY AND SATURDAY. ANY
RESIDUAL RN/SN SHOWERS WILL BE QUICKLY CUT OFF BY 12Z AS SHORTWAVE
RIDGE AND ASSOCIATED BUBBLE OF SUBSIDENCE/SURFACE HIGH PRESSURE FOLD
INTO THE GREAT LAKES. SHOULD BE MOSTLY SUNNY BY AFTERNOON AS
NEGATIVE THETA-E ADVECTION FINALLY ERODES THIN LAYER OF MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION IN CAA REGIME. HIGH TEMPS WILL
MAKE A RUN AT UPPER 40S BY LATE AFTERNOON AS WINDS START TO BACK.
LOW 50S MAY EVEN BE POSSIBLE IF MORNING CLOUDS DISSIPATE QUICKER
THAN EXPECTED. MUCH WARMER CONDITIONS FOR SATURDAY AS SW FLOW/WAA
RAMP UP AHEAD OF NEXT WAVE. UPPER 50S TO NEAR 60F POSSIBLE GIVEN
850MB TEMPS AROUND 4C...BUT THE TRADEOFF WILL BE INCREASING HIGH-
BASED CLOUDS ESPECIALLY IN OUR NORTHWEST BY AFTERNOON AS MIDLEVEL
WARM/MOIST AIR ADVECTION INCREASES.
NEXT CHANCE OF RAIN WILL ARRIVE EARLY SUNDAY MORNING AS ANOTHER
VIGOROUS SHORTWAVE RIPPLES THROUGH THE REGION. STILL SOME
INCONSISTENCIES AMONG THE LATEST DETERMINISTIC GUIDANCE TO WORK OUT.
HOWEVER DOES APPEAR TO BE SOME CONSENSUS FOR SURFACE WAVE
DEVELOPMENT ALONG BAROCLINIC ZONE WITH DECENT SHOT OF SOME MODERATE
RAIN AS MIDLEVEL TROUGH TAKES ON AT LEAST A NEUTRAL TILT. BEST
PRECIP CHANCES LOOK TO BE SUNDAY AFTERNOON INTO SUNDAY NIGHT.
THERMAL PROFILES SHOULD BE WARM ENOUGH FOR ALL RAIN...THOUGH IT IS
WORTH NOTING THE ECMWF SOLUTION WOULD SUPPORT THE POSSIBILITY OF A
FEW WET SNOWFLAKES MIXING IN ON BACK EDGE OF EXITING DEFORMATION
BAND. STILL PLENTY OF TIME TO WATCH THIS EVENT AND SUSPECT THERE
WILL BE CHANGES SINCE PARENT JET ENERGY IS STILL OVER THE NORTH
PACIFIC. QUIET WEATHER THEREAFTER AS SPRAWLING MID/UPPER RIDGE AND
SURFACE HIGH MOVE OVER THE REGION. COOL AT FIRST BUT SHOULD WARM UP
AGAIN BY MIDWEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 631 AM EDT THU MAR 24 2016
LATEST SURFACE OBSERVATIONS ARE BEGINNING TO INDICATE A NORTHWARD
ADVANCEMENT OF STALLED FRONTAL BOUNDARY ACROSS NORTHERN INDIANA
EARLY THIS MORNING. CANNOT RULE OUT IFR CIGS OVER NEXT FEW HOURS
BUT IT APPEARS GREATER POTENTIAL OF ADDITIONAL IFR CIGS AT KSBN
SHOULD HOLD OFF UNTIL MIDDAY IN ASSOCIATION WITH GREATER RAIN
POTENTIAL AND APPROACH OF SFC REFLECTION. WITH SFC BOUNDARY HAVING
LIFTED NORTH OF KFWA...VFR OR HIGHER END MVFR CONDITIONS SHOULD
PERSIST THROUGH MIDDAY WITH POTENTIAL OF FUEL ALTERNATE CRITERIA
LIKELY HOLDING OFF UNTIL THIS AFTERNOON IN ASSOCIATION WITH
GREATER RAINFALL THREAT. IN TERMS OF PRECIP POTENTIAL...A BRIEF
LULL WILL CONTINUE THROUGH MID MORNING BUT A VIGOROUS UPPER LEVEL
WAVE AND DEEPER MOISTURE PROFILES WILL SUPPORT RAIN OVERSPREADING
TERMINALS IN THE 16Z-20Z TIMEFRAME. SOME ISO-SCT THUNDER IS
POSSIBLE...PARTICULARLY AT KFWA WHERE SFC BASED INSTABILITY SHOULD
BE A BIT MORE IMPRESSIVE. HOWEVER AT THIS FORECAST DISTANCE WILL
MAINTAIN JUST A VCTS MENTION AT KFWA WITH LINGERING UNCERTAINTY IN
INSTABILITY MAGNITUDE. WINDS TO SHIFT NORTHWEST TONIGHT BEHIND THE
COLD FRONT WITH SOME LINGERING SCATTERED LIGHT RAIN SHOWERS/PATCHY
DRIZZLE THIS EVENING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING FROM 8 PM THIS EVENING TO 5 AM EDT FRIDAY FOR
LMZ043-046.
&&
$$
SYNOPSIS...MARSILI
SHORT TERM...MARSILI
LONG TERM...AGD
AVIATION...MARSILI
VISIT US AT WW.WEATHER.GOV/IWX
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
638 AM EDT THU MAR 24 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 241200Z TAFS/...
ISSUED AT 638 AM EDT THU MAR 24 2016
SOME SHOWER ACTIVITY OVER WEST CENTRAL AND SOUTHWEST INDIANA MAY IMPACT THE
TERMINALS EARLY THIS MORNING. HOWEVER...SHORT TERM MODEL GUIDANCE SUGGESTS
THE MAIN LIFT/MORE WIDESPREAD SHOWER ACTIVITY PROBABLY WON/T MOVE INTO THE
AREA UNTIL THE MID TO LATE MORNING HOURS...ROUGHLY AFTER 241400Z. DECENT
POTENTIAL FOR EMBEDDED LIGHTNING STRIKES TOWARDS MIDDAY INTO THE
AFTERNOON...NEAR THE LEADING EDGE OF THE DRY SLOT AND SURFACE COLD FRONT AS
MID LEVEL LAPSE RATES STEEPEN. BEST POTENTIAL FOR IFR VISIBILITY RESTRICTIONS
APPEAR TO BE IN THIS REGION AS WELL. PRECIPITATION WILL END BY LATE AFTERNOON
WITH THE ARRIVAL OF THE DRY SLOT.
CEILINGS 040-050 EARLY THIS MORNING WILL GRADUALLY LOWER INTO THE 020-025 RANGE
AS THE MAIN PRECIPITATION AREA ARRIVES. BRIEFLY LOWER CEILINGS POSSIBLE IN
HEAVIER PRECIPITATION CELLS. CEILINGS WILL PROBABLY LIFT FOR A TIME LATE THIS
AFTERNOON UNDER THE DRY SLOT.
SHOULD SEE SURFACE WIND GUSTS APPROACHING 30 KTS FROM 180-200 DEGREES BY LATE
MORNING AS A 55-60 LOW LEVEL JET CORE MOVES OVERHEAD. WINDS EXPECTED TO VEER
AROUND TO 230-250 DEGREES BY LATE AFTERNOON AFTER FRONTAL PASSAGE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
427 AM EDT THU MAR 24 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 240900Z KIND TAF UPDATE/...
ISSUED AT 427 AM EDT THU MAR 24 2016
SOME SHOWER ACTIVITY STARTING TO DEVELOP OVER SOUTHWEST INDIANA MAY
IMPACT THE KIND TERMINAL AFTER ABOUT 241000Z...BUT APPEARS THESE SHOWERS
WILL BE RATHER LIGHT WITH LITTLE TO NO VISIBILITY RESTRICTION. SHORT
TERM MODEL GUIDANCE SUGGEST BETTER LIFT/MORE WIDESPREAD RAINFALL MORE
TOWARDS THE LATE MORNING HOURS.
WILL ALSO PUSH BACK THE TIMING OF THE LOWER MVFR CEILINGS MORE TOWARDS THE
EXPECTED ARRIVAL OF THE WIDESPREAD PRECIPITATION.
PREVIOUS DISCUSSION FOLLOWS.
GOOD CONFIDENCE THAT VFR CONDITIONS WILL DETERIORATE TO MVFR SHORTLY
AFTER ISSUANCE TIME WITH INCREASING SHOWER COVERAGE AS UPPER WAVES
MOVE NORTHEAST OVER THE AREA AHEAD OF A STRONG SYSTEM NORTHWEST OF
KANSAS CITY.
SCATTERED SHOWERS WERE OVER THE LAF AND HUF AREAS LATE THIS EVENING
AND SHOULD CONTINUE TO INCREASE IN COVERAGE AND SPREAD SOUTHEAST
OVERNIGHT. WILL START OFF WITH VCSH AND VFR CEILINGS AND THEN MVFR
IN LIGHT SHOWERS 07Z-09Z. SHOWERS COULD BE MODERATE OR POSSIBLY EVEN
HEAVY AT TIMES WITH BRIEF IFR. COULD ALSO SEE SOME EMBEDDED THUNDER
AFTER 10Z...BUT CONFIDENCE IS TOO LOW TO MENTION. THE ASSOCIATED
COLD FRONT SHOULD MOVE TO NEAR LAF AND HUF 18Z-20Z AND 21Z-23Z AT
IND. AFTER THAT...COVERAGE OF POST-FRONTAL SHOWERS AND ISOLATED
STORMS EXPECTED TO BE TOO SPARSE TO MENTION AND FLYING CONDITIONS
LIKELY TO IMPROVE TO VFR.
SOUTH WINDS TO 10 KNOTS OR MORE WILL CONTINUE OVERNIGHT WITH GUSTS
TO NEAR 20 KNOTS. WINDS WILL PICK UP AGAIN AFTER 15Z AND START OFF
FROM THE SOUTH 15-18 KNOTS WITH GUSTS TO 25 KNOTS. THE WIND WILL
VEER TO THE SOUTHWEST...WEST AND FINALLY NORTHWEST IN THE WAKE OF
THE COLD FRONT. IT WILL REMAIN BREEZY AFTER SUNSET WITH SUSTAINED
WINDS TO 15 KNOTS AND GUSTS TO 20 KNOTS OR MORE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...MK/JAS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
359 AM EDT THU MAR 24 2016
.SYNOPSIS...
ISSUED AT 342 AM EDT THU MAR 24 2016
AN UPPER LEVEL DISTURBANCE ACROSS THE CENTRAL UNITED STATES WILL
APPROACH THE AREA TODAY. THIS DISTURBANCE WILL INTERACT WITH A
FRONTAL BOUNDARY ACROSS THE AREA TO PRODUCE WIDESPREAD RAIN
SHOWERS ALONG WITH A FEW THUNDERSTORMS THROUGH THIS AFTERNOON.
GUSTY SOUTH WINDS ARE EXPECTED IN ADVANCE OF THE COLD FRONT WITH
THIS SYSTEM...PARTICULARLY ACROSS FAR NORTHEAST INDIANA AND
NORTHWEST OHIO TODAY. SCATTERED RAIN SHOWERS MAY LINGER INTO THIS
EVENING...BUT DRIER AND COOLER AIR MOVING INTO THE REGION BEHIND A
COLD FRONT WILL GRADUALLY END THE CHANCES OF ADDITIONAL RAIN
SHOWERS OVERNIGHT. CLOUDS WILL DIMINISH ON FRIDAY WITH COOLER
TEMPERATURES. HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE
MID 50S ACROSS NORTHWEST INDIANA AND FAR SOUTHWEST LOWER
MICHIGAN...TO THE MID 60S ACROSS NORTHWEST OHIO. LOW TEMPERATURES
TONIGHT WILL DROP INTO THE LOWER TO MID 30S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM EDT THU MAR 24 2016
STALLED SURFACE BOUNDARY REMAINS SPRAWLED FROM FAR NORTHERN INDIANA
INTO FAR NORTHWEST OHIO THIS MORNING. BROAD ISENTROPIC LIFT/MOISTURE
ADVECTION CONTINUES IN ASSOCIATION WITH THIS BOUNDARY AND HAS
LARGELY BEEN RESPONSIBLE FOR WIDESPREAD RAIN SHOWERS/DRIZZLE ACROSS
PRIMARILY NORTHERN HALF OF THE FORECAST AREA DURING THE OVERNIGHT
HOURS. EXPECTING THAT SOME DIMINISHMENT IN RAIN SHOWER COVERAGE WILL
OCCUR ACROSS THE NORTH DURING THE EARLY-MID MORNING HOURS AS MORE
FAVORED ZONE OF ISENTROPIC ASCENT PER 295K-300K LAYER PROGS LIFTS
NORTHWARD ACROSS CENTRAL LOWER MICHIGAN. RAIN POTENTIAL TO RAMP
UP FROM WEST TO EAST FROM MID MORNING THROUGH THE AFTERNOON AS
POTENT PV ANOMALY OVERSPREADS MID MS VALLEY/SOUTHERN GREAT LAKES
ALONG WITH A CORRESPONDING DOWNSTREAM LOW/MID LEVEL FGEN RESPONSE.
SOME WEAK ELEVATED INSTABILITY IS NOTED PER SPC RUC ANALYSIS AT
06Z ACROSS THE FAR NORTH...BUT PRIMARY INSTABILITY AXIS OF NOTE
FOR LOCAL AREA WILL BE IMMEDIATELY PRECEDING SFC COLD FRONTAL
BOUNDARY THIS AFTERNOON WITH SOME DIFFERENTIAL THERMAL ADVECTION
SETTING UP THIS NARROW CORRIDOR OF INSTABILITY. MAGNITUDE OF
INSTABILITY IS EXPECTING TO BE ON THE MARGINAL SIDE...GENERALLY IN
THE 500-800 J/KG RANGE...BUT A BRIEF POTENTIAL OF NEAR SFC/SFC
BASED INSTABILITY MAY EXIST ACROSS SOUTHEAST HALF OF THE AREA LATE
MORNING-LATE AFTERNOON. THIS WEAK INSTABILITY COMBINED WITH FAIRLY
IMPRESSIVE DEEP LAYER SHEAR MAGNITUDES OF 50-60 KNOTS DOES POSE
SOME CONCERN FOR SMALL LINEAR BOWING SEGMENTS. THIS THREAT REMAINS
HIGHLY CONDITIONAL ON INSTABILITY AND OVERALL SEVERE THREAT
REMAINS LOW. NOT MUCH CHANGE FROM PREVIOUS FORECAST THINKING WITH
ISOLD SEVERE POTENTIAL AT BEST TODAY GIVEN LIMITED
INSTABILITY...WITH ISOLATED STRONGER WIND GUSTS AS THE MAIN
THREAT.
TEMPERATURE FORECAST REMAINS A CHALLENGING ONE IN THE NEAR
TERM...WITH A 20 DEGREE NORTH TO SOUTH TEMPERATURE DIFFERENTIAL
ACROSS THE FORECAST AREA THIS MORNING. SFC BOUNDARY HAS REMAINED
SOMEWHAT STUBBORNLY ANCHORED ACROSS FAR NORTHERN INDIANA...BUT
SHOULD START TO SEE SOME NORTHWARD RETREAT OF THIS BOUNDARY IN THE
09Z-15Z TIMEFRAME. THIS SHOULD PUT BULK OF FORECAST AREA IN WARM
SECTOR...ALBEIT FOR A VERY BRIEF TIME ACROSS THE FAR NORTHWEST AS
SFC REFLECTION REACHES NORTHWEST INDIANA LATE MORNING. OVERALL NOT
MUCH CHANGE TO INHERITED MAX TEMPS...WITH JUST A SLIGHT UPWARD
ADJUSTMENTS INTO THE MID 60S FAR SOUTH CENTRAL/EAST WHERE RESIDENCE
TIME OF WARM SECTOR WILL BE PROLONGED...AND WHERE A MORE DELAYED
PRECIP TIMING IS ANTICIPATED. ANOTHER LOWER END CONCERN TODAY WILL
BE A BRIEF POTENTIAL OF NEAR ADVISORY OR ADVISORY LEVEL SOUTH-
SOUTHWEST WINDS AHEAD OF THIS SYSTEM. SFC REFLECTION SHOULD BE IN A
SLIGHT DEEPENING MODE THIS AFTERNOON WITH AN AXIS OF FAIRLY
STRONG SFC PRESSURE FALLS EXPECTED TO DEVELOP/MIGRATE ACROSS
SOUTHEAST LOWER MICHIGAN. THESE PRESSURE FALLS COMBINED WITH
POTENTIALLY BETTER MIXING WHERE SFC TEMPS ARE EXPECTED TO REACH
THE MID 60S...COULD ALLOW FOR A BRIEF WINDOW OF 35 TO 45 MPH WIND
GUSTS ACROSS THE FAR EAST IN THE 16Z-21Z TIMEFRAME GIVEN STRONG
LOW LEVEL WIND FIELD. HAVE HELD OFF ON ANY WIND ADVISORY AT THIS
TIME GIVEN LOW CONFIDENCE ON DEPTH OF MIXING AND RELATIVELY SHORT
DURATION OF THIS POTENTIAL.
DRY SLOT TO OVERSPREAD THE AREA TONIGHT AS COLDER AIR ADVECTS
SOUTHEASTWARD BEHIND THE FRONT DIMINISHING PRECIP COVERAGE IN THE
EVENING...ALTHOUGH DEFORMATION ZONE MAY PROLONG AT LEAST SCATTERED
SHOWERS ACROSS THE FAR NORTHWEST. ANY CHANGEOVER TO SNOW SHOULD BE
OF MINIMAL PRECIP COVERAGE/INTENSITY AND NO SNOW ACCUMULATION IS
ANTICIPATED AT THIS TIME. END OF THIS PRECIP EVENT COULD TURN OUT
TO BE MORE DRIZZLY IN NATURE TONIGHT...BUT CURRENTLY NOT EXPECTING
ANY SIGNIFICANT IMPACTS FROM POTENTIAL DRIZZLE OR FREEZING DRIZZLE
TONIGHT.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 342 AM EDT THU MAR 24 2016
MUCH MORE BENIGN WEATHER ANTICIPATED FOR FRIDAY AND SATURDAY. ANY
RESIDUAL RN/SN SHOWERS WILL BE QUICKLY CUT OFF BY 12Z AS SHORTWAVE
RIDGE AND ASSOCIATED BUBBLE OF SUBSIDENCE/SURFACE HIGH PRESSURE FOLD
INTO THE GREAT LAKES. SHOULD BE MOSTLY SUNNY BY AFTERNOON AS
NEGATIVE THETA-E ADVECTION FINALLY ERODES THIN LAYER OF MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION IN CAA REGIME. HIGH TEMPS WILL
MAKE A RUN AT UPPER 40S BY LATE AFTERNOON AS WINDS START TO BACK.
LOW 50S MAY EVEN BE POSSIBLE IF MORNING CLOUDS DISSIPATE QUICKER
THAN EXPECTED. MUCH WARMER CONDITIONS FOR SATURDAY AS SW FLOW/WAA
RAMP UP AHEAD OF NEXT WAVE. UPPER 50S TO NEAR 60F POSSIBLE GIVEN
850MB TEMPS AROUND 4C...BUT THE TRADEOFF WILL BE INCREASING HIGH-
BASED CLOUDS ESPECIALLY IN OUR NORTHWEST BY AFTERNOON AS MIDLEVEL
WARM/MOIST AIR ADVECTION INCREASES.
NEXT CHANCE OF RAIN WILL ARRIVE EARLY SUNDAY MORNING AS ANOTHER
VIGOROUS SHORTWAVE RIPPLES THROUGH THE REGION. STILL SOME
INCONSISTENCIES AMONG THE LATEST DETERMINISTIC GUIDANCE TO WORK OUT.
HOWEVER DOES APPEAR TO BE SOME CONSENSUS FOR SURFACE WAVE
DEVELOPMENT ALONG BAROCLINIC ZONE WITH DECENT SHOT OF SOME MODERATE
RAIN AS MIDLEVEL TROUGH TAKES ON AT LEAST A NEUTRAL TILT. BEST
PRECIP CHANCES LOOK TO BE SUNDAY AFTERNOON INTO SUNDAY NIGHT.
THERMAL PROFILES SHOULD BE WARM ENOUGH FOR ALL RAIN...THOUGH IT IS
WORTH NOTING THE ECMWF SOLUTION WOULD SUPPORT THE POSSIBILITY OF A
FEW WET SNOWFLAKES MIXING IN ON BACK EDGE OF EXITING DEFORMATION
BAND. STILL PLENTY OF TIME TO WATCH THIS EVENT AND SUSPECT THERE
WILL BE CHANGES SINCE PARENT JET ENERGY IS STILL OVER THE NORTH
PACIFIC. QUIET WEATHER THEREAFTER AS SPRAWLING MID/UPPER RIDGE AND
SURFACE HIGH MOVE OVER THE REGION. COOL AT FIRST BUT SHOULD WARM UP
AGAIN BY MIDWEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 113 AM EDT THU MAR 24 2016
FRONTAL BOUNDARY REMAINS ANCHORED APPROXIMATELY ALONG THE ROUTE 6
CORRIDOR EARLY THIS MORNING. AN INTENSIFYING LOW LEVEL JET
CUTTING ACROSS THIS BOUNDARY HAS ALLOWED FOR RENEWED POSITIVE
THETAE ADVECTION AND EXPANDING AREA OF LIGHT RAIN/DRIZZLE ACROSS
MUCH OF NORTHERN INDIANA. DURING THE REMAINDER OF THE EARLY
MORNING HOURS...SFC FRONTAL BOUNDARY IS EXPECTED TO CREEP
NORTHWARD ALONG WITH A NORTHWARD SHIFT TO STRONGEST ISENTROPIC
UPGLIDE. THESE TRENDS SHOULD TEND TO DIMINISH RAIN COVERAGE TOWARD
DAYBREAK FOR A BRIEF TIME. IN THE MEANWHILE...IFR/LIFR CONDITIONS
WILL REMAIN LIKELY ALONG AND TO THE NORTH OF THIS BOUNDARY AT
KSBN OVER NEXT SEVERAL HOURS...WITH SOME IMPROVEMENT TO MAINLY IFR
EXPECTED AFTER 09Z OR 10Z. FOCUS FOR THE REMAINDER OF THE FORECAST
WILL BE EASTWARD PROGRESSION OF STRONG VORT MAX ASSOCIATED WITH
UPPER TROUGH AND APPROACHING FRONTAL BOUNDARY. RAIN WILL INCREASE
IN INTENSITY ACROSS NORTHWEST INDIANA AFTER DAYBREAK AND
EVENTUALLY FOR KFWA TOWARD MIDDAY. SOME POTENTIAL OF THUNDER WILL
EXIST AT KFWA AS WEAK INSTABILITY AXIS PRECEDES THE FRONT. HAVE
CARRIED VCTS AT KFWA WITH THE 06Z TAFS MAINLY FROM 18Z-21Z.
OUTSIDE OF SHOWERS WINDS WILL BECOME QUITE GUSTY IN THE WARM
SECTOR...WITH A PERIOD OF SOUTH WIND GUSTS OF 30 TO 35 KNOTS
EXPECTED AT KFWA LATE MORNING/EARLY AFTERNOON. WINDS TO SHIFT
WEST-NORTHWEST BEHIND THE FRONT TONIGHT...WITH GUSTS TO 20 TO 25
KNOTS AND POTENTIAL OF SOME SCATTERED LINGERING RAIN SHOWERS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING FROM 5 PM THIS AFTERNOON TO 5 AM EDT FRIDAY FOR
LMZ043-046.
&&
$$
SYNOPSIS...MARSILI
SHORT TERM...MARSILI
LONG TERM...AGD
AVIATION...MARSILI
VISIT US AT WW.WEATHER.GOV/IWX
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
329 AM EDT THU MAR 24 2016
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 240600Z TAF ISSUANCE/...
ISSUED AT 1145 PM EDT WED MAR 23 2016
GOOD CONFIDENCE THAT VFR CONDITIONS WILL DETERIORATE TO MVFR SHORTLY
AFTER ISSUANCE TIME WITH INCREASING SHOWER COVERAGE AS UPPER WAVES
MOVE NORTHEAST OVER THE AREA AHEAD OF A STRONG SYSTEM NORTHWEST OF
KANSAS CITY.
SCATTERED SHOWERS WERE OVER THE LAF AND HUF AREAS LATE THIS EVENING
AND SHOULD CONTINUE TO INCREASE IN COVERAGE AND SPREAD SOUTHEAST
OVERNIGHT. WILL START OFF WITH VCSH AND VFR CEILINGS AND THEN MVFR
IN LIGHT SHOWERS 07Z-09Z. SHOWERS COULD BE MODERATE OR POSSIBLY EVEN
HEAVY AT TIMES WITH BRIEF IFR. COULD ALSO SEE SOME EMBEDDED THUNDER
AFTER 10Z...BUT CONFIDENCE IS TOO LOW TO MENTION. THE ASSOCIATED
COLD FRONT SHOULD MOVE TO NEAR LAF AND HUF 18Z-20Z AND 21Z-23Z AT
IND. AFTER THAT...COVERAGE OF POST-FRONTAL SHOWERS AND ISOLATED
STORMS EXPECTED TO BE TOO SPARSE TO MENTION AND FLYING CONDITIONS
LIKELY TO IMPROVE TO VFR.
SOUTH WINDS TO 10 KNOTS OR MORE WILL CONTINUE OVERNIGHT WITH GUSTS
TO NEAR 20 KNOTS. WINDS WILL PICK UP AGAIN AFTER 15Z AND START OFF
FROM THE SOUTH 15-18 KNOTS WITH GUSTS TO 25 KNOTS. THE WIND WILL
VEER TO THE SOUTHWEST...WEST AND FINALLY NORTHWEST IN THE WAKE OF
THE COLD FRONT. IT WILL REMAIN BREEZY AFTER SUNSET WITH SUSTAINED
WINDS TO 15 KNOTS AND GUSTS TO 20 KNOTS OR MORE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...MK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1136 AM MDT THU MAR 24 2016
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 309 AM MDT THU MAR 24 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS CLOSED
UPPER LOW CENTERED OVER NORTHEAST KS...WITH SHORTWAVE RIDGING
BUILDING ACROSS THE CENTRAL ROCKIES TOWARD THE NORTHERN PLAINS ON
THE BACK SIDE OF THIS SYSTEM. THERE ARE STILL A FEW WEAK PLUMES OF
DEEPER MOISTURE ROTATING AROUND THE BACK SIDE OF THIS SYSTEM JUST
EAST OF OUR CWA. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS
EASTERN COLORADO WITH STRONG SURFACE LOW PRESSURE ACROSS NORTHERN
MISSOURI. TIGHT SURFACE GRADIENT BETWEEN THESE FEATURES IS STILL IN
PLACE ACROSS THE EASTERN 2/3 OF OUR CWA AND IS SLOWLY RETREATING
EASTWARD.
TODAY-TONIGHT...UPPER LEVEL SHORTWAVE TROUGH TRANSITION ACROSS OUR
CWA WITHIN NW FLOW ALOFT WITH WEAK LEE TROUGH BEGINNING TO REDEVELOP
BY LATE THIS AFTERNOON. DRY CONDITIONS ARE EXPECTED WITH MAIN
FORECAST CHALLENGE BEING IMPACTS OF SNOW PACK ON HIGHS/LOWS. GROUND
TEMPERATURES ARE WARM ENOUGH STILL THAT MELTING SHOULD OCCUR FAIRLY
QUICKLY AFTER SUNRISE. POTENTIAL EXISTS FOR HIGHS TO REACH THE 50S
TODAY...HOWEVER LOCATIONS IN OUR NORTH/NORTHWEST MAY STRUGGLE TO
REACH THE LOW 40S IF SNOW PACK LIMITS DIURNAL HEATING. DEEPEST SNOW
PACK IS IN YUMA COUNTY AND THIS IS WHERE I HAVE LEAST CONFIDENCE IN
HIGHS TODAY. LOWS TONIGHT SHOULD DROP FAIRLY QUICKLY...HOWEVER LEE
TROUGH BEGINS TO DEEPEN AS ANOTHER FRONT APPROACHES THE REGION WITH
INCREASING BL WINDS. I LEANED LOW TEMP FORECAST TOWARDS 2M GUIDANCE
(WARMER BLENDS) AS MIXING MAY PREVENT BETTER RADIATIONAL COOLING.
FRIDAY-SATURDAY NIGHT...THE NEXT UPPER LEVEL TROUGH MOVES INTO THE
PLAINS WITH TWO SPLITS OCCURRING FRIDAY AND A FRONTAL PASSAGE DURING
THE DAY FRIDAY OR FRIDAY NIGHT. CONFIDENCE IS NOT PARTICULARLY HIGH
DUE TO VARIANCES IN HOW MODELS SHOW FRONTAL TIMING AND MOISTURE
RETURN BETWEEN THESE SPLIT SHORTWAVE TROUGHS. WHERE PRECIP OCCURS IT
APPEARS THAT TEMP/MOISTURE PROFILES SHOULD SUPPORT MAINLY A SNOW
EVENT. BEST CHANCE FOR PRECIP APPEARS TO BE WHEN THE SOUTHERN
SHORTWAVE ROTATES TROUGH THE PLAINS (LIKELY CENTERED SOUTH OF OUR
FORECAST AREA).
00Z NAM WAS THE STRONGEST ON THIS FEATURE WITH A CLOSED H7 CENTER
PASSING NEAR OUR CWA...HOWEVER 06Z TRACK IS FURTHER SOUTH AND
SLIGHTLY MORE PROGRESSIVE. LATEST ECMWF SHOWS THE H7 LOW CLOSING
OFF FURTHER SOUTHEAST AND DEEPENING OVER EASTERN KS...AND THE GFS
ONLY SHOWS A WEAK OPEN WAVE AT H5/H7. QUITE A BIT OF
VARIANCE...WHICH LOWERS CONFIDENCE IN POTENTIAL IMPACTS.
STRONGEST OVERLAPPING PRECIP SIGNAL IS IN OUR SOUTHERN CWA LATE
FRIDAY NIGHT THROUGH SATURDAY MORNING REGARDLESS OF WHICH MODEL WE
CHOOSE...SO I KEPT CHANCE POPS IN THIS AREA. CONSENSUS FAVORS SNOW
ACCUMULATIONS GENERALLY 1-2" (ASSUMING MAINLY SNOW DURING THE
EVENT). WILL NEED TO CONTINUE MONITORING TRENDS.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 309 AM MDT THU MAR 24 2016
SUNDAY THROUGH TUESDAY WILL BE DRY WITH WARMING TEMPERATURES AS AN
UPPER RIDGE MOVES OVER THE CENTRAL HIGH PLAINS. SURFACE HIGH
PRESSURE MOVES INTO THE SOUTHERN PLAINS AS A LEE TROUGH BEGINS TO
DEEPEN ALONG THE FRONT RANGE MONDAY NIGHT AHEAD OF THE NEXT MAIN
UPPER LOW THAT MOVES INTO THE CENTRAL NEVADA. HIGH TEMPERATURES IN
THE 50S ON SUNDAY WILL WARM INTO THE 70S BY TUESDAY. THE INITIAL
SHORT WAVE TROUGH LIFTS OUT OF THE UPPER LOW ACROSS NORTHEAST
COLORADO AND INTO WESTERN NORTH DAKOTA AND WESTERN NEBRASKA BY MID
DAY WEDNESDAY ALONG WITH A COINCIDENT SURFACE LOW CENTER. THERE IS A
POSSIBILITY OF SHOWERS AND THUNDERSTORMS DEVELOPING OVER THE FAR
EASTERN SECTIONS OF THE FORECAST AREA TUESDAY EVENING INTO EARLY
WEDNESDAY AHEAD OF THE SURFACE THROUGH THAT MOVES EASTWARD.
FROM WEDNESDAY THROUGH THURSDAY MODELS BECOME MORE DIVERGENT ON HOW
THE COMBINATION OF THE UPPER LOW OVER THE WEST AND THE LOW LIFTING
INTO THE NORTHERN PLAINS IS HANDLED. THE GFS TENDS TO SEPARATE
THESE FEATURES MORE WITH THE LOW LIFTING INTO THE NORTHERN PLAINS
MAKING BETTER PROGRESS TOWARDS THE GREAT LAKES REGION THAN THE ECMWF
THAT TENDS TO KEEP THE FEATURES LINKED INTO A SINGLE ELONGATED
TROUGH THAT EXTENDS FROM THE NORTHERN HIGH PLAINS TO OFF THE COAST
OF SOUTHERN CALIFORNIA. EITHER WAY IT APPEARS TEMPERATURES WILL
COOL ACROSS THE CENTRAL HIGH PLAINS REGION WEDNESDAY AND THURSDAY AS
THERE WILL BE A COLD FRONT THAT MOVES ACROSS THE REGION WEDNESDAY
NIGHT WITH A CHANCE OF LIGHT RAIN SHOWERS SPREADING ACROSS THE AREA
...CHANGING TO LIGHT SNOW WEDNESDAY NIGHT...AND BACK TO RAIN ON
THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1126 AM MDT THU MAR 24 2016
VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF PERIOD FOR BOTH KGLD
AND KMCK. LOW LEVEL WIND SHEAR IS EXPECTED TO IMPACT BOTH
TERMINALS FOR A FEW HOURS STARTING AROUND 10Z FRIDAY. THE LLWS
WILL BE AROUND 700FT FOR KGLD AND 1000FT FOR KMCK...BOTH FROM
AROUND 190 DEGREES UP TO 45 KTS. CLOUDS WILL START TO MOVE INTO
THE TAF SITES BETWEEN 05Z AND 10Z...WITH CEILINGS DROPPING DOWN
TO AROUND 10000FT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...CLT
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
1222 PM CDT THU MAR 24 2016
...Updated Aviation and Synopsis...
.SYNOPSIS...
ISSUED AT 1219 PM CDT THU MAR 24 2016
At 12z Thursday a 500mb Low was located over northwest Missouri.
Further west another, weaker, 500mb trough was located over
Washington and southern British Columbia. Between these two system
a 700mb and 500mb northwest flow was present across the Central
Rockies. at 12z Thursday the 850mb wind at Dodge City was 50
knots. At the surface an area of high pressure was located over
northeast Colorado.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 214 AM CDT THU MAR 24 2016
The upper level low driving all the sensible weather last night will
continue to move away from the forecast region. In the wake, high pressure
will build in. The net result is gradually decreasing wind magnitudes
through the day. The strongest winds is expected right now and winds
by the afternoon should be NNW 10-20 mph. Otherwise, highs today will
be in the 50s with the warmest readings near the Oklahoma border. Other
that light precipitation early this morning, the day will be dry with
pops trending to zero percent. Critical fire weather conditions are
not expected this afternoon as relative humidities will be higher given
the cooler temperatures. For tonight, weak High Plains lee troughing
will developing with a light southerly wind continuing through the overnight.
Mins in the lower 30s are expected.
.LONG TERM...(Friday THROUGH Wednesday)
ISSUED AT 214 AM CDT THU MAR 24 2016
On Friday, a warm air-advection pattern is expected, particularly from
the SE Zones. Compressional warming ahead of a front will send highs
back into the 70s across south-central Kansas. Moisture will be limited
ahead of the front and even any precip is squeezed out, it will be mid
level moisture (a few high based showers). Fairly low confidence in
this happening, although do have high pops out west with the upslope
component to the winds is stronger. A better chance for precip comes
late Saturday and into Sunday as a compact vortmax ejects out. The ECMWF
and NAM indicate accumulating snowfall where the GFS is mainly dry.
Will put more bias towards the EC and have the highest pops along the
Oklahoma border closer to the vortmax and stronger isentropic lift.
Snow amounts are fairly conservative in the grids right now, although
several inches of snow cannot be ruled out given the model QPF trends
from the NAM and ECMWF. The event should start as rain but then transition
to snow as intense cold air advection develops. Beyond that, a drier
forecast is expected with moderating temperatures.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Friday AFTERNOON)
ISSUED AT 1219 PM CDT THU MAR 24 2016
An area of high pressure at the surface will build across western
Kansas this afternoon. Gusty northwest winds mid day will decrease
to 10 knots or less and by 00z Friday. These winds at less than 10
knots will become south southeast overnight as a surface trough of
low pressure begins to develop along the lee of the Rockies. South
winds will increase into the 20 to near 25 knot range after 15z
Friday. RAP and HRRR indicating an increasing in mid to high level
moisture late tonight but these cloud bases later tonight and
Friday will be at or above 10000 ft AGL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 56 33 68 35 / 0 0 10 20
GCK 57 31 65 33 / 0 0 10 30
EHA 59 32 66 34 / 0 0 10 30
LBL 59 32 68 35 / 0 0 10 20
HYS 51 30 64 34 / 0 0 10 20
P28 57 32 70 39 / 0 0 10 20
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...Burgert
SHORT TERM...Sugden
LONG TERM...Sugden
AVIATION...Burgert
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
636 AM CDT THU MAR 24 2016
.UPDATE...
Issued at 636 AM CDT THU MAR 24 2016
Will probably let the wind advisory expire at 7 AM this morning.
Latest model guidance progs the pressure gradient to relax through
the morning and winds are currently below advisory levels. So
while northwest winds will remain gusty to around 30 MPH, think
the winds are at their strongest now and should gradually weaken
through the day.
The wrap around snow showers continue to make steady progress east
with the upper deformation zone. Think all of the precip should
exit the forecast around 10 am with only minor accumulations.
&&
.SHORT TERM...(Today and Tonight)
Issued at 337 AM CDT THU MAR 24 2016
0730Z satellite imagery shows the upper low over the forecast area
with light rain and snow gradually expanding over north central KS.
The surface low has moved into northwest MO based on objective
analysis.
The progress of the upper closed low has been a little slower than
previously expected. As a result, the winds have been slower to
increase in speed, although strong northwest winds are noted just
west of the forecast area. Think winds are still going to trend
stronger through the morning as models maintain a strong pressure
gradient over the area. But the winds may not be as strong as
previously expected. Plan to continue to wind advisory through 12Z
to monitor trends but at this point think the advisory may be
allowed to expire.
Models are in agreement that the upper low will move east of the
forecast area by late morning and should take the light precip with
it as much of the forcing is mainly from deformation within the
upper trough. Because of this have held onto some POPs across
northeast. Once the wave passes east, dry air advection in the low
levels should allow for the low clouds to clear out with skies
becoming mostly sunny during the afternoon. With some cold air
advection through the day and cloud cover initially, highs look to
only be in the upper 40s and around 50. If the sun breaks out a
little sooner, highs may be a degree or two warmer. By tonight, weak
surface ridging is progged to move across the area with only some
thin high clouds. This should allow winds to become light and
variable helping the boundary layer to radiate out. With this in
mind, have lows in the in the mid and upper 20s.
.LONG TERM...(Friday through Wednesday)
Issued at 337 AM CDT THU MAR 24 2016
Conditions on Friday will still be favorable for elevated fire
weather concerns mainly along and southwest of a line from Concordia
to Manhattan to Emporia line. No headlines are needed at this time
due to conditions likely to remain under criteria with winds gusting
to less than 25 mph from the south/southwest and RH values being
probably in the mid 20s. With a relatively low amplitude trough
advecting into the Northern Plains, it doesn`t appear that wind and
thermal fields will support conditions that could cause a Red Flag
Warning at this time. Confidence in this is on the medium end right
now as it does appear that a LLJ will be just to the west of the
area over East Central KS. As a shortwave deepens over the Northern
Plains, a weak cold front does get pushed into the region Friday
evening and stalls out over northeast KS. Meanwhile a more
amplified southern stream shortwave digs into the Central and
Southern Rockies helping to draw in more gulf moisture return to the
region. With the previously mentioned boundary in place, there
should be enough lift to see chance end POPs over a majority of the
weekend and especially on Sunday. Varying model solutions would
suggest more precip if the EC and NAM verify. However, if the GFS,
which is slightly faster than the EC and not as aggressive with the
deepening of the trough, verifies then it stands to reason precip
amounts will be on the lighter side and come to an end early on
Sunday. Most precip should be in the form of rain especially south
of I-70, but there could be enough cooling with slightly enough cold
air advection to see at least a rain/snow mix north of I-70.
A potentially more interesting system enters the picture on
Wednesday time frame as the next longwave trough becomes highly
amplified and deepens over the Central Rockies. Wind and thermal
fields look fairly impressive once again. While an impressive jet
streak advects over the region late Wednesday with 0-6 bulk shear of
around 90kts and steep mid level lapse rates in place, a fairly
strong EML may be in place. It is possible that with enough cooling
aloft that this cap could be degraded throughout time. Moisture
return will be a big question too as to just how much will actually
advect into the region before the trough pushes through. Mid 50
dewpoints with a strong dryline may just be enough though for this
time of year to aid in storm development. Something to watch over
the next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday Morning)
Issued at 603 AM CDT THU MAR 24 2016
There may be a brief period of IFR VSBY as snow showers move
through the terminals. But for the most part I expect conditions
to remain MVFR with a RASN mix changing to -SN at TOP and FOE.
The clouds will be slower to scatter out once the precip comes to
an end and have timed the clearing based on the NAM/GFS. For some
reason the RAP is slowing down with the clearing and I`m not ready
to buy into with dry low level air moving in behind the system.
VFR conditions should prevail by the early afternoon and through
the night tonight.
&&
.TOP Watches/Warnings/Advisories...
Wind Advisory until 7 AM CDT this morning for KSZ008>012-020>024-
026-034>040-054>056-058-059.
&&
$$
UPDATE...Wolters
SHORT TERM...Wolters
LONG TERM...Drake
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
522 AM MDT THU MAR 24 2016
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 309 AM MDT THU MAR 24 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS CLOSED
UPPER LOW CENTERED OVER NORTHEAST KS...WITH SHORTWAVE RIDGING
BUILDING ACROSS THE CENTRAL ROCKIES TOWARD THE NORTHERN PLAINS ON
THE BACK SIDE OF THIS SYSTEM. THERE ARE STILL A FEW WEAK PLUMES OF
DEEPER MOISTURE ROTATING AROUND THE BACK SIDE OF THIS SYSTEM JUST
EAST OF OUR CWA. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS
EASTERN COLORADO WITH STRONG SURFACE LOW PRESSURE ACROSS NORTHERN
MISSOURI. TIGHT SURFACE GRADIENT BETWEEN THESE FEATURES IS STILL IN
PLACE ACROSS THE EASTERN 2/3 OF OUR CWA AND IS SLOWLY RETREATING
EASTWARD.
TODAY-TONIGHT...UPPER LEVEL SHORTWAVE TROUGH TRANSITION ACROSS OUR
CWA WITHIN NW FLOW ALOFT WITH WEAK LEE TROUGH BEGINNING TO REDEVELOP
BY LATE THIS AFTERNOON. DRY CONDITIONS ARE EXPECTED WITH MAIN
FORECAST CHALLENGE BEING IMPACTS OF SNOW PACK ON HIGHS/LOWS. GROUND
TEMPERATURES ARE WARM ENOUGH STILL THAT MELTING SHOULD OCCUR FAIRLY
QUICKLY AFTER SUNRISE. POTENTIAL EXISTS FOR HIGHS TO REACH THE 50S
TODAY...HOWEVER LOCATIONS IN OUR NORTH/NORTHWEST MAY STRUGGLE TO
REACH THE LOW 40S IF SNOW PACK LIMITS DIURNAL HEATING. DEEPEST SNOW
PACK IS IN YUMA COUNTY AND THIS IS WHERE I HAVE LEAST CONFIDENCE IN
HIGHS TODAY. LOWS TONIGHT SHOULD DROP FAIRLY QUICKLY...HOWEVER LEE
TROUGH BEGINS TO DEEPEN AS ANOTHER FRONT APPROACHES THE REGION WITH
INCREASING BL WINDS. I LEANED LOW TEMP FORECAST TOWARDS 2M GUIDANCE
(WARMER BLENDS) AS MIXING MAY PREVENT BETTER RADIATIONAL COOLING.
FRIDAY-SATURDAY NIGHT...THE NEXT UPPER LEVEL TROUGH MOVES INTO THE
PLAINS WITH TWO SPLITS OCCURRING FRIDAY AND A FRONTAL PASSAGE DURING
THE DAY FRIDAY OR FRIDAY NIGHT. CONFIDENCE IS NOT PARTICULARLY HIGH
DUE TO VARIANCES IN HOW MODELS SHOW FRONTAL TIMING AND MOISTURE
RETURN BETWEEN THESE SPLIT SHORTWAVE TROUGHS. WHERE PRECIP OCCURS IT
APPEARS THAT TEMP/MOISTURE PROFILES SHOULD SUPPORT MAINLY A SNOW
EVENT. BEST CHANCE FOR PRECIP APPEARS TO BE WHEN THE SOUTHERN
SHORTWAVE ROTATES TROUGH THE PLAINS (LIKELY CENTERED SOUTH OF OUR
FORECAST AREA).
00Z NAM WAS THE STRONGEST ON THIS FEATURE WITH A CLOSED H7 CENTER
PASSING NEAR OUR CWA...HOWEVER 06Z TRACK IS FURTHER SOUTH AND
SLIGHTLY MORE PROGRESSIVE. LATEST ECMWF SHOWS THE H7 LOW CLOSING
OFF FURTHER SOUTHEAST AND DEEPENING OVER EASTERN KS...AND THE GFS
ONLY SHOWS A WEAK OPEN WAVE AT H5/H7. QUITE A BIT OF
VARIANCE...WHICH LOWERS CONFIDENCE IN POTENTIAL IMPACTS.
STRONGEST OVERLAPPING PRECIP SIGNAL IS IN OUR SOUTHERN CWA LATE
FRIDAY NIGHT THROUGH SATURDAY MORNING REGARDLESS OF WHICH MODEL WE
CHOOSE...SO I KEPT CHANCE POPS IN THIS AREA. CONSENSUS FAVORS SNOW
ACCUMULATIONS GENERALLY 1-2" (ASSUMING MAINLY SNOW DURING THE
EVENT). WILL NEED TO CONTINUE MONITORING TRENDS.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 309 AM MDT THU MAR 24 2016
SUNDAY THROUGH TUESDAY WILL BE DRY WITH WARMING TEMPERATURES AS AN
UPPER RIDGE MOVES OVER THE CENTRAL HIGH PLAINS. SURFACE HIGH
PRESSURE MOVES INTO THE SOUTHERN PLAINS AS A LEE TROUGH BEGINS TO
DEEPEN ALONG THE FRONT RANGE MONDAY NIGHT AHEAD OF THE NEXT MAIN
UPPER LOW THAT MOVES INTO THE CENTRAL NEVADA. HIGH TEMPERATURES IN
THE 50S ON SUNDAY WILL WARM INTO THE 70S BY TUESDAY. THE INITIAL
SHORT WAVE TROUGH LIFTS OUT OF THE UPPER LOW ACROSS NORTHEAST
COLORADO AND INTO WESTERN NORTH DAKOTA AND WESTERN NEBRASKA BY MID
DAY WEDNESDAY ALONG WITH A COINCIDENT SURFACE LOW CENTER. THERE IS A
POSSIBILITY OF SHOWERS AND THUNDERSTORMS DEVELOPING OVER THE FAR
EASTERN SECTIONS OF THE FORECAST AREA TUESDAY EVENING INTO EARLY
WEDNESDAY AHEAD OF THE SURFACE THROUGH THAT MOVES EASTWARD.
FROM WEDNESDAY THROUGH THURSDAY MODELS BECOME MORE DIVERGENT ON HOW
THE COMBINATION OF THE UPPER LOW OVER THE WEST AND THE LOW LIFTING
INTO THE NORTHERN PLAINS IS HANDLED. THE GFS TENDS TO SEPARATE
THESE FEATURES MORE WITH THE LOW LIFTING INTO THE NORTHERN PLAINS
MAKING BETTER PROGRESS TOWARDS THE GREAT LAKES REGION THAN THE ECMWF
THAT TENDS TO KEEP THE FEATURES LINKED INTO A SINGLE ELONGATED
TROUGH THAT EXTENDS FROM THE NORTHERN HIGH PLAINS TO OFF THE COAST
OF SOUTHERN CALIFORNIA. EITHER WAY IT APPEARS TEMPERATURES WILL
COOL ACROSS THE CENTRAL HIGH PLAINS REGION WEDNESDAY AND THURSDAY AS
THERE WILL BE A COLD FRONT THAT MOVES ACROSS THE REGION WEDNESDAY
NIGHT WITH A CHANCE OF LIGHT RAIN SHOWERS SPREADING ACROSS THE AREA
...CHANGING TO LIGHT SNOW WEDNESDAY NIGHT...AND BACK TO RAIN ON
THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 522 AM MDT THU MAR 24 2016
VFR CONDITIONS SHOULD CONTINUE THROUGH THE TAF PERIOD...WITH
INCREASING 10-25KFT CLOUDS AFTER 00Z. THERE HAVE BEEN A FEW
PATCHES OF 1500-3000KFT STRATUS...HOWEVER THIS HAS BEEN ISOLATED
AND SHOWING A DECREASING TREND ON SATELLITE (MATCHING SHORT RANGE
GUIDANCE. AS A RESULT THIS IS NOT LIKELY TO IMPACT EITHER KGLD OR
KMCK TERMINAL THIS MORNING. GUSTY WINDS WILL DECREASE THIS
MORNING AS HIGH PRESSURE MOVES EAST OVER BOTH KGLD AND KMCK
TERMINALS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...DR
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
603 AM CDT THU MAR 24 2016
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 337 AM CDT THU MAR 24 2016
0730Z satellite imagery shows the upper low over the forecast area
with light rain and snow gradually expanding over north central KS.
The surface low has moved into northwest MO based on objective
analysis.
The progress of the upper closed low has been a little slower than
previously expected. As a result, the winds have been slower to
increase in speed, although strong northwest winds are noted just
west of the forecast area. Think winds are still going to trend
stronger through the morning as models maintain a strong pressure
gradient over the area. But the winds may not be as strong as
previously expected. Plan to continue to wind advisory through 12Z
to monitor trends but at this point think the advisory may be
allowed to expire.
Models are in agreement that the upper low will move east of the
forecast area by late morning and should take the light precip with
it as much of the forcing is mainly from deformation within the
upper trough. Because of this have held onto some POPs across
northeast. Once the wave passes east, dry air advection in the low
levels should allow for the low clouds to clear out with skies
becoming mostly sunny during the afternoon. With some cold air
advection through the day and cloud cover initially, highs look to
only be in the upper 40s and around 50. If the sun breaks out a
little sooner, highs may be a degree or two warmer. By tonight, weak
surface ridging is progged to move across the area with only some
thin high clouds. This should allow winds to become light and
variable helping the boundary layer to radiate out. With this in
mind, have lows in the in the mid and upper 20s.
.LONG TERM...(Friday through Wednesday)
Issued at 337 AM CDT THU MAR 24 2016
Conditions on Friday will still be favorable for elevated fire
weather concerns mainly along and southwest of a line from Concordia
to Manhattan to Emporia line. No headlines are needed at this time
due to conditions likely to remain under criteria with winds gusting
to less than 25 mph from the south/southwest and RH values being
probably in the mid 20s. With a relatively low amplitude trough
advecting into the Northern Plains, it doesn`t appear that wind and
thermal fields will support conditions that could cause a Red Flag
Warning at this time. Confidence in this is on the medium end right
now as it does appear that a LLJ will be just to the west of the
area over East Central KS. As a shortwave deepens over the Northern
Plains, a weak cold front does get pushed into the region Friday
evening and stalls out over northeast KS. Meanwhile a more
amplified southern stream shortwave digs into the Central and
Southern Rockies helping to draw in more gulf moisture return to the
region. With the previously mentioned boundary in place, there
should be enough lift to see chance end POPs over a majority of the
weekend and especially on Sunday. Varying model solutions would
suggest more precip if the EC and NAM verify. However, if the GFS,
which is slightly faster than the EC and not as aggressive with the
deepening of the trough, verifies then it stands to reason precip
amounts will be on the lighter side and come to an end early on
Sunday. Most precip should be in the form of rain especially south
of I-70, but there could be enough cooling with slightly enough cold
air advection to see at least a rain/snow mix north of I-70.
A potentially more interesting system enters the picture on
Wednesday time frame as the next longwave trough becomes highly
amplified and deepens over the Central Rockies. Wind and thermal
fields look fairly impressive once again. While an impressive jet
streak advects over the region late Wednesday with 0-6 bulk shear of
around 90kts and steep mid level lapse rates in place, a fairly
strong EML may be in place. It is possible that with enough cooling
aloft that this cap could be degraded throughout time. Moisture
return will be a big question too as to just how much will actually
advect into the region before the trough pushes through. Mid 50
dewpoints with a strong dryline may just be enough though for this
time of year to aid in storm development. Something to watch over
the next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday Morning)
Issued at 603 AM CDT THU MAR 24 2016
There may be a brief period of IFR VSBY as snow showers move
through the terminals. But for the most part I expect conditions
to remain MVFR with a RASN mix changing to -SN at TOP and FOE.
The clouds will be slower to scatter out once the precip comes to
an end and have timed the clearing based on the NAM/GFS. For some
reason the RAP is slowing down with the clearing and I`m not ready
to buy into with dry low level air moving in behind the system.
VFR conditions should prevail by the early afternoon and through
the night tonight.
&&
.TOP Watches/Warnings/Advisories...
Wind Advisory until 7 AM CDT this morning for KSZ008>012-020>024-
026-034>040-054>056-058-059.
&&
$$
SHORT TERM...Wolters
LONG TERM...Drake
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
310 AM MDT THU MAR 24 2016
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 309 AM MDT THU MAR 24 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS CLOSED
UPPER LOW CENTERED OVER NORTHEAST KS...WITH SHORTWAVE RIDGING
BUILDING ACROSS THE CENTRAL ROCKIES TOWARD THE NORTHERN PLAINS ON
THE BACK SIDE OF THIS SYSTEM. THERE ARE STILL A FEW WEAK PLUMES OF
DEEPER MOISTURE ROTATING AROUND THE BACK SIDE OF THIS SYSTEM JUST
EAST OF OUR CWA. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS
EASTERN COLORADO WITH STRONG SURFACE LOW PRESSURE ACROSS NORTHERN
MISSOURI. TIGHT SURFACE GRADIENT BETWEEN THESE FEATURES IS STILL IN
PLACE ACROSS THE EASTERN 2/3 OF OUR CWA AND IS SLOWLY RETREATING
EASTWARD.
TODAY-TONIGHT...UPPER LEVEL SHORTWAVE TROUGH TRANSITION ACROSS OUR
CWA WITHIN NW FLOW ALOFT WITH WEAK LEE TROUGH BEGINNING TO REDEVELOP
BY LATE THIS AFTERNOON. DRY CONDITIONS ARE EXPECTED WITH MAIN
FORECAST CHALLENGE BEING IMPACTS OF SNOW PACK ON HIGHS/LOWS. GROUND
TEMPERATURES ARE WARM ENOUGH STILL THAT MELTING SHOULD OCCUR FAIRLY
QUICKLY AFTER SUNRISE. POTENTIAL EXISTS FOR HIGHS TO REACH THE 50S
TODAY...HOWEVER LOCATIONS IN OUR NORTH/NORTHWEST MAY STRUGGLE TO
REACH THE LOW 40S IF SNOW PACK LIMITS DIURNAL HEATING. DEEPEST SNOW
PACK IS IN YUMA COUNTY AND THIS IS WHERE I HAVE LEAST CONFIDENCE IN
HIGHS TODAY. LOWS TONIGHT SHOULD DROP FAIRLY QUICKLY...HOWEVER LEE
TROUGH BEGINS TO DEEPEN AS ANOTHER FRONT APPROACHES THE REGION WITH
INCREASING BL WINDS. I LEANED LOW TEMP FORECAST TOWARDS 2M GUIDANCE
(WARMER BLENDS) AS MIXING MAY PREVENT BETTER RADIATIONAL COOLING.
FRIDAY-SATURDAY NIGHT...THE NEXT UPPER LEVEL TROUGH MOVES INTO THE
PLAINS WITH TWO SPLITS OCCURRING FRIDAY AND A FRONTAL PASSAGE DURING
THE DAY FRIDAY OR FRIDAY NIGHT. CONFIDENCE IS NOT PARTICULARLY HIGH
DUE TO VARIANCES IN HOW MODELS SHOW FRONTAL TIMING AND MOISTURE
RETURN BETWEEN THESE SPLIT SHORTWAVE TROUGHS. WHERE PRECIP OCCURS IT
APPEARS THAT TEMP/MOISTURE PROFILES SHOULD SUPPORT MAINLY A SNOW
EVENT. BEST CHANCE FOR PRECIP APPEARS TO BE WHEN THE SOUTHERN
SHORTWAVE ROTATES TROUGH THE PLAINS (LIKELY CENTERED SOUTH OF OUR
FORECAST AREA).
00Z NAM WAS THE STRONGEST ON THIS FEATURE WITH A CLOSED H7 CENTER
PASSING NEAR OUR CWA...HOWEVER 06Z TRACK IS FURTHER SOUTH AND
SLIGHTLY MORE PROGRESSIVE. LATEST ECMWF SHOWS THE H7 LOW CLOSING
OFF FURTHER SOUTHEAST AND DEEPENING OVER EASTERN KS...AND THE GFS
ONLY SHOWS A WEAK OPEN WAVE AT H5/H7. QUITE A BIT OF
VARIANCE...WHICH LOWERS CONFIDENCE IN POTENTIAL IMPACTS.
STRONGEST OVERLAPPING PRECIP SIGNAL IS IN OUR SOUTHERN CWA LATE
FRIDAY NIGHT THROUGH SATURDAY MORNING REGARDLESS OF WHICH MODEL WE
CHOOSE...SO I KEPT CHANCE POPS IN THIS AREA. CONSENSUS FAVORS SNOW
ACCUMULATIONS GENERALLY 1-2" (ASSUMING MAINLY SNOW DURING THE
EVENT). WILL NEED TO CONTINUE MONITORING TRENDS.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 309 AM MDT THU MAR 24 2016
SUNDAY THROUGH TUESDAY WILL BE DRY WITH WARMING TEMPERATURES AS AN
UPPER RIDGE MOVES OVER THE CENTRAL HIGH PLAINS. SURFACE HIGH
PRESSURE MOVES INTO THE SOUTHERN PLAINS AS A LEE TROUGH BEGINS TO
DEEPEN ALONG THE FRONT RANGE MONDAY NIGHT AHEAD OF THE NEXT MAIN
UPPER LOW THAT MOVES INTO THE CENTRAL NEVADA. HIGH TEMPERATURES IN
THE 50S ON SUNDAY WILL WARM INTO THE 70S BY TUESDAY. THE INITIAL
SHORT WAVE TROUGH LIFTS OUT OF THE UPPER LOW ACROSS NORTHEAST
COLORADO AND INTO WESTERN NORTH DAKOTA AND WESTERN NEBRASKA BY MID
DAY WEDNESDAY ALONG WITH A COINCIDENT SURFACE LOW CENTER. THERE IS A
POSSIBILITY OF SHOWERS AND THUNDERSTORMS DEVELOPING OVER THE FAR
EASTERN SECTIONS OF THE FORECAST AREA TUESDAY EVENING INTO EARLY
WEDNESDAY AHEAD OF THE SURFACE THROUGH THAT MOVES EASTWARD.
FROM WEDNESDAY THROUGH THURSDAY MODELS BECOME MORE DIVERGENT ON HOW
THE COMBINATION OF THE UPPER LOW OVER THE WEST AND THE LOW LIFTING
INTO THE NORTHERN PLAINS IS HANDLED. THE GFS TENDS TO SEPARATE
THESE FEATURES MORE WITH THE LOW LIFTING INTO THE NORTHERN PLAINS
MAKING BETTER PROGRESS TOWARDS THE GREAT LAKES REGION THAN THE ECMWF
THAT TENDS TO KEEP THE FEATURES LINKED INTO A SINGLE ELONGATED
TROUGH THAT EXTENDS FROM THE NORTHERN HIGH PLAINS TO OFF THE COAST
OF SOUTHERN CALIFORNIA. EITHER WAY IT APPEARS TEMPERATURES WILL
COOL ACROSS THE CENTRAL HIGH PLAINS REGION WEDNESDAY AND THURSDAY AS
THERE WILL BE A COLD FRONT THAT MOVES ACROSS THE REGION WEDNESDAY
NIGHT WITH A CHANCE OF LIGHT RAIN SHOWERS SPREADING ACROSS THE AREA
...CHANGING TO LIGHT SNOW WEDNESDAY NIGHT...AND BACK TO RAIN ON
THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1056 PM MDT WED MAR 23 2016
SNOW WILL CONTINUE TO WIND DOWN DURING THE OVERNIGHT HOURS WITH
IFR TRANSITIONING TO VFR BY 12Z. SURFACE WINDS WILL ALSO GRADUALLY
DIMINISH DURING THAT TIME. THERE COULD BE LINGERING VISIBILITY
RESTRICTIONS DUE TO BLOWING SNOW IN THE 3-5SM RANGE...IMPROVING
THURSDAY MORNING AS WINDS GO LIGHT FROM THE WEST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...024
AREA FORECAST DISCUSSION
NWS JACKSON KY
432 PM EDT THU MAR 24 2016
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 432 PM EDT THU MAR 24 2016
AT MID AFTERNOON A COLD FRONT STRETCHED FROM DEEP LOW PRESSURE AT
THE NORTHERN END OF INDIANA TO EXTREME WESTERN KENTUCKY AND ON
SOUTHWESTWARD. SHOWERS WERE OCCURRING AHEAD OF THE FRONT...WITH A
FEW THUNDERSTORMS NEAR THE FRONT. THE LEADING EDGE OF PRECIP WILL
ADVANCE EASTWARD OUT OF KY EARLY THIS EVENING. SOUTH TO SOUTHWEST
WINDS WERE STILL KICKING UP AT TIMES AT MID AFTERNOON...ESPECIALLY
OVER THE WESTERN EDGE OF THE JKL FORECAST AREA. WITH A NPW FOR
WIND ALREADY IN PLACE...WILL LET IT RIDE FOR NOW...WITH STILL
SOME SMALL POTENTIAL TO REACH ADVISORY OR LAKE WIND ADVISORY LATE
TODAY. HOWEVER...IT WOULD APPEAR THAT ASIDE FROM CONVECTION...THE
GREATEST WIND THREAT HAS FADED. ANY THUNDERSTORMS OR HEAVY SHOWERS
ALONG/AHEAD OF THE FRONT HAVE A POTENTIAL TO BRING STRONG
WINDS...AND WE CONTINUE IN A MARGINAL THREAT OF SEVERE STORMS FROM
SPC.
SHOWERS WILL END WITH FROPA...BUT FORECAST SOUNDINGS SHOW A
POTENTIAL FOR SOME DRIZZLE IN LINGERING LOW LEVEL MOISTURE INTO
FRIDAY MORNING. THIS WILL END AND CLOUDS WILL BREAK UP ON FRIDAY
AS SURFACE HIGH PRESSURE PASSES BY TO OUR NORTH. DRIER AIR AND
CLEARING SKIES WILL PRESENT A FROST THREAT IN OUR COLDER VALLEYS
ON FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 302 PM EDT THU MAR 24 2016
EXTENDED PORTION OF THE FORECAST WILL FEATURE PATCHY FROST EARLY
SATURDAY MORNING...MAINLY IN VALLEY LOCATIONS...ABOVE NORMAL
TEMPERATURES FOR MOST OF THE PERIOD...AND TWO PERIODS OF
PRECIPITATION. THE INITIAL BOUT OF RAIN IS ON TRACK FOR SUNDAY
THROUGH MONDAY. BASED ON THE LATEST MODEL DATA...PRECIPITATION
ONSET WILL BE SLOWER THAN PREVIOUSLY FORECAST...WITH THE FIRST
SHOWERS AND STORMS PROGGED TO ENTER OUR SOUTHWESTERN COUNTIES
AROUND 12Z ON SUNDAY. THE RAIN IS EXPECTED TO BE MOST WIDESPREAD
FROM SUNDAY AFTERNOON THROUGH LATE SUNDAY NIGHT...AS A WAVE OF LOW
PRESSURE MOVES OUT OF THE CENTRAL PLAINS...ACROSS THE MID
MISSISSIPPI VALLEY AND THEN ACROSS THE OHIO VALLEY REGION SUNDAY
AND SUNDAY NIGHT. THE LATEST FORECAST MODELS ARE SHOWING JUST
ENOUGH INSTABILITY AND LIFT TO PERHAPS SPARK A FEW THUNDERSTORMS
SUNDAY AFTERNOON AND EVENING. THE CHANCES FOR THUNDER WILL
STEADILY DIMINISH SUNDAY NIGHT AS WE LOSE THE HEATING OF THE DAY
AND THE WEATHER SYSTEM MOVES OFF QUICKLY TO OUR EAST...TAKING ITS
LIFT WITH IT.
WE SHOULD THEN SEE AN EXTENDED BREAK FROM PRECIPITATION FROM
MONDAY NIGHT THROUGH WEDNESDAY...AS A RIDGE OF HIGH PRESSURE
TEMPORARILY SETS UP SHOP ACROSS THE SOUTHERN AND SOUTHEASTERN
CONUS DURING THAT TIME. THE MODELS TRY TO BRING ANOTHER WEATHER
SYSTEM THROUGH THE EASTERN THIRD OF THE CONUS FOR THE MIDDLE OF
THE WEEK. IN GENERAL THE SLOWER ECMWF MODEL WAS USED TO ADJUST THE
MODEL BLEND FORECAST AS WE ARE NOW IN THE WARM SEASON WITH LESS
COLD AIR TO PUSH THIS SYSTEM EASTWARD. THE FORECAST IS CALLING FOR
ISOLATED RAIN SHOWERS TO ENTER EASTERN KENTUCKY FROM THE SOUTHWEST
LATE WEDNESDAY EVENING...WITH ISOLATED TO SCATTERED SHOWERS
OVERSPREADING THE AREA WEDNESDAY NIGHT INTO EARLY THURSDAY
MORNING.
TEMPERATURES ARE EXPECTED TO BE ABOVE NORMAL
SATURDAY...SUNDAY...AND AGAIN ON WEDNESDAY...AS RIDGES OF HIGH
PRESSURE RULE THE WEATHER ON THOSE DAYS. CONDITIONS WILL COOL OFF
QUITE A BIT ON MONDAY AND TUESDAY...AS COOLER AIR SPILLS INTO THE
AREA BEHIND A DEPARTING WEATHER SYSTEM. WE COULD EASILY SEE HIGHS
REACH THE UPPER 60S ON SATURDAY AND WEDNESDAY...AND THE LOW TO MID
70S ON SUNDAY. THE COOLEST DAYS OF THE WEEK LOOK TO MONDAY AND
TUESDAY...WHEN THE MERCURY MAY ONLY TOP OUT IN THE MID TO UPPER
50S FOR MOST LOCATIONS. OVERNIGHT LOWS WILL BE IN THE 30S AND
40S ACROSS THE AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 756 AM EDT THU MAR 24 2016
A LOW LEVEL JET OF 35 TO 40 KTS OUT OF THE SOUTH SOUTHWEST AT
AROUND 2K FEET AGL WILL CONTINUE TO BRING WIND SHEAR CONCERNS TO
THE TAF SITES THROUGH AROUND 14Z. ONCE THE INVERSION MIXES
OUT...STRONG AND GUSTY SOUTH TO SOUTHWEST WINDS WILL ENGAGE.
SUSTAINED SPEEDS WILL RANGE FROM 15 TO 20 KTS...WITH GUSTS IN THE
25 TO 35 KT RANGE. A COLD FRONT WILL MOVE THROUGH THE AREA LATE
THIS AFTERNOON INTO THIS EVENING...BRINGING SHOWERS AND PERHAPS A
FEW THUNDERSTORMS WITH IT. CEILINGS/VISIBILITIES WILL DROP DOWN TO
THE LOW VFR/MVFR RANGE...WITH WINDS SHIFTING FROM THE SOUTHWEST TO
WEST. CEILINGS WILL CONTINUE TO LOWER LATE THIS EVENING BEHIND THE
FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR KYZ044-050>052-
058>060-068-069-079-080-083>085-104-106-108-111-114.
LAKE WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR KYZ086>088-
107-109-110-112-113-115>120.
&&
$$
SHORT TERM...HAL
LONG TERM...AR
AVIATION...GEOGERIAN
Area Forecast Discussion
National Weather Service Paducah KY
309 PM CDT THU MAR 24 2016
.SHORT TERM...(This evening through Saturday Night)
Issued at 309 PM CDT Thu Mar 24 2016
The band of showers from Owensboro to Madisonville will slowly
push east northeast out of the region by late this afternoon.
We cannot rule out a few lightning strikes, but any significant
intensification should not occur until it passes out of our area.
Recent shower development along the actual cold front near the
Wabash River should struggle to survive as it moves into a worked
over airmass.
The entire area should be dry by 00Z this evening, but low clouds
will overspread the area behind the front, and linger for much of
the night. West northwest winds will slowly weaken through the
night, but they are not expected to go calm by morning. The
combination of clouds and winds should keep temperatures from
dropping down to the freezing mark and frost from forming in the
morning.
Considerable uncertainty exists in how long clouds may linger
Friday, but tried to lean toward the warm side of guidance for
highs. The surface high will still be in control of the region
Friday night, but winds will not be calm. Temperatures should drop
into the 30s over most of the area, but a freeze or frost is
not likely at this time. Plenty of sunshine and a return to south
winds should allow for a nice warm up on Saturday. More
confidently leaned toward the warm side of the guidance envelope
for highs.
An inverted surface trough will develop southwest to northeast
through the region Saturday night, as our Easter storm system
approaches. We should stay dry through sunrise Sunday morning, but
clouds will be on the increase from the west. Guidance is locked
in to the middle 40s for lows so did not deviate much at all.
.LONG TERM...(Sunday through Thursday Night)
Issued at 309 PM CDT Thu Mar 24 2016
In the extended forecast period, the ECMWF guidance is still
preferred from previous forecast shifts given it consistency in
space and time across the WFO PAH forecast area. In addition to the
blended guidance, added a little weighting toward the ECMWF solution
with the first system on Sunday...with confidence greater than 50
percent. Have lower confidence on the early onset of precipitation
with the next system next Wednesday.
The pattern has set up with a progressive mean trough over the
conterminous U.S. through the period, with intervening shortwave
ridges. This would place precipitation event over the area about
every 2-3 days.
With the continual changes from warm to cold advection regimes and
mixing, diurnal ranges will be minimized somewhat, reducing the
concern for late night/early morning freeze potential or record
afternoon highs. Although evapotranspiration is increasing this time
of year, have doubt that there will be large scale drying between
systems.
A compact short wave moves through Sunday and Sunday evening, with
some intensification at the low-middle levels of the atmosphere. At
this point, the best potential for thunderstorms seems to be across
the Delta region of Southeast Missouri and West Kentucky, along and
just east of the forecast surface low moving over the area. Given
the likelihood for outdoor activities Sunday, will continue to
highlight in the Hazardous Weather Outlook.
The system next Wednesday/Thursday is somewhat less distinct, with
periodic shortwaves generating precipitation in a broad southwest
flow regime.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1246 PM CDT Thu Mar 24 2016
Showers should push through KOWB in the next hour or two with MVFR
or even brief IFR conditions. A stray lightning strike cannot be
ruled out. Otherwise winds will veer from south through west
through the afternoon and gust well over 20kts. A large area of
low VFR or MVFR ceilings will overspread the area from mid
afternoon through early evening. Confidence in the duration of the
ceilings is not great. Could see scattering/clearing before
daybreak at KCGI and KPAH, but figure on ceilings lasting through
the end of the period at KEVV and KOWB.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
SHORT TERM...DRS
LONG TERM...Smith
AVIATION...DRS
Area Forecast Discussion
National Weather Service Paducah KY
309 PM CDT THU MAR 24 2016
.SHORT TERM...(This evening through Saturday Night)
Issued at 309 PM CDT Thu Mar 24 2016
The band of showers from Owensboro to Madisonville will slowly
push east northeast out of the region by late this afternoon.
We cannot rule out a few lightning strikes, but any significant
intensification should not occur until it passes out of our area.
Recent shower development along the actual cold front near the
Wabash River should struggle to survive as it moves into a worked
over airmass.
The entire area should be dry by 00Z this evening, but low clouds
will overspread the area behind the front, and linger for much of
the night. West northwest winds will slowly weaken through the
night, but they are not expected to go calm by morning. The
combination of clouds and winds should keep temperatures from
dropping down to the freezing mark and frost from forming in the
morning.
Considerable uncertainty exists in how long clouds may linger
Friday, but tried to lean toward the warm side of guidance for
highs. The surface high will still be in control of the region
Friday night, but winds will not be calm. Temperatures should drop
into the 30s over most of the area, but a freeze or frost is
not likely at this time. Plenty of sunshine and a return to south
winds should allow for a nice warm up on Saturday. More
confidently leaned toward the warm side of the guidance envelope
for highs.
An inverted surface trough will develop southwest to northeast
through the region Saturday night, as our Easter storm system
approaches. We should stay dry through sunrise Sunday morning, but
clouds will be on the increase from the west. Guidance is locked
in to the middle 40s for lows so did not deviate much at all.
.LONG TERM...(Sunday through Thursday Night)
Issued at 309 PM CDT Thu Mar 24 2016
In the extended forecast period, the ECMWF guidance is still
preferred from previous forecast shifts given it consistency in
space and time across the WFO PAH forecast area. In addition to the
blended guidance, added a little weighting toward the ECMWF solution
with the first system on Sunday...with confidence greater than 50
percent. Have lower confidence on the early onset of precipitation
with the next system next Wednesday.
The pattern has set up with a progressive mean trough over the
conterminous U.S. through the period, with intervening shortwave
ridges. This would place precipitation event over the area about
every 2-3 days.
With the continual changes from warm to cold advection regimes and
mixing, diurnal ranges will be minimized somewhat, reducing the
concern for late night/early morning freeze potential or record
afternoon highs. Although evapotranspiration is increasing this time
of year, have doubt that there will be large scale drying between
systems.
A compact short wave moves through Sunday and Sunday evening, with
some intensification at the low-middle levels of the atmosphere. At
this point, the best potential for thunderstorms seems to be across
the Delta region of Southeast Missouri and West Kentucky, along and
just east of the forecast surface low moving over the area. Given
the likelihood for outdoor activities Sunday, will continue to
highlight in the Hazardous Weather Outlook.
The system next Wednesday/Thursday is somewhat less distinct, with
periodic shortwaves generating precipitation in a broad southwest
flow regime.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1246 PM CDT Thu Mar 24 2016
Showers should push through KOWB in the next hour or two with MVFR
or even brief IFR conditions. A stray lightning strike cannot be
ruled out. Otherwise winds will veer from south through west
through the afternoon and gust well over 20kts. A large area of
low VFR or MVFR ceilings will overspread the area from mid
afternoon through early evening. Confidence in the duration of the
ceilings is not great. Could see scattering/clearing before
daybreak at KCGI and KPAH, but figure on ceilings lasting through
the end of the period at KEVV and KOWB.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
SHORT TERM...DRS
LONG TERM...Smith
AVIATION...DRS
Area Forecast Discussion
National Weather Service Louisville KY
305 PM EDT THU MAR 24 2016
.SHORT TERM (Now through Friday Night)...
Issued at 256 PM EDT Thu Mar 24 2016
The concerns this afternoon will continue to be the potential for
severe weather, as well as gradient wind gusts. Gradient winds have
been gusting mainly in the upper 30s to around 40. However, there
have been some gusts as high as 45 mph. The wind advisory continues
until 23Z, but will continue to monitor gusts as it may be able to
be let go before then.
The rain that has moved across central KY today has helped to
stabilize the area. However, SPC mesoanalysis does show an area of
slight instability across west central KY. In addition the 0-6 km
shear values are around 60 knots across the region. Mesoscale models
do suggest that the instability will spread eastward this afternoon
into western portions of the forecast area before weakening towards
the early evening hours. The HRRR continues to show strengthening of
the line of storms right along the cold front into the evening
hours. All things considered, there is still a slight chance for
some strong to severe storms this afternoon with hail and wind
gusts.
The storms should move out of the area by around 03Z or so with some
light showers continuing across the Bluegrass overnight. Rain should
move out completely by daybreak Friday, with dry conditions
expected Friday night.
Temperatures will fall in the wake of the cold front overnight into
the mid 30s to lower 40s. Despite the low temps, frost formation is
not expected as winds will remain elevated overnight. Highs tomorrow
will be much cooler, in the lower to mid 50s. Lows Friday night will
dip into the mid to upper 30s. With light winds and high pressure,
some frost will be possible early Saturday morning.
.LONG TERM (Saturday through Thursday)...
Issued at 305 PM EDT Thu Mar 24 2016
Saturday will remain dry with high pressure ridging in from the
northeast. Temperature will warm into the 60s under mostly sunny
skies. Lows Saturday night will be much warmer, in the 40s areawide.
A trough will dig into the Plains on Sunday and cross the lower Ohio
Valley Sunday night. The best chance for showers and thunderstorms
with this system still looks to be late Sunday afternoon into Sunday
night. Given the dry weather for much of the day ahead of this
system, temperatures will warm into the upper 60s to lower 70s. The
severe potential does not look overly impressive with this system,
but a few strong storms will not be out of the question. The rain
should move out on Monday morning.
Tuesday through Wednesday look to be dry as high pressure builds
into the area. In the wake of the system Sunday night, temps on
Monday will be back in the 50s. We will then see a warm up through
mid week with temps back into the mid to upper 60s. The next chance
for rain will come Wednesday night into Thursday.
&&
.AVIATION (18Z TAF Update)...
Updated at 115 PM EDT Thu Mar 24 2016
A cold front will push through the terminals during the upcoming
forecast period bringing a few rounds of showers and thunderstorms
to the region. The best chances of thunderstorms will be in the
early part of the TAF period from 24/18Z through 25/01Z.
For this afternoon/evening, we expect VFR to MVFR conditions at the
terminals with scattered showers within the vicinity of the
airports. Some thunderstorms will be possible later this afternoon
and evening and will plan on keeping the VCTS in the ongoing TAF
package. Gradient winds will remain strong with southwest winds of
15-20kts and gusts up over 30kts at times.
For the overnight period (25/03Z and after), cold front is expected
to be clearing the region. Winds will shift from the SW to the W
and remain elevated with speeds of 10-13kts and gusts in the 15-
20kts. These winds should subside overnight and towards dawn on
Friday. Initially ceilings will be near the MVFR/VFR thresholds but
are expected to drop solidly into the MVFR category overnight with
ceilings running from FL015-020.
The outlook for Friday suggests improving conditions throughout the
day. Ceilings will start off at MVFR levels but are expected to rise
to VFR by afternoon with a light northwest wind of 5-7kts.
&&
.LMK Watches/Warnings/Advisories...
KY...Wind Advisory until 7 PM EDT /6 PM CDT/ this evening for
KYZ028>043-045>049-053>057-062>067-071>078-081-082.
IN...Wind Advisory until 7 PM EDT this evening for INZ078-079-091-092.
&&
$$
Short Term........EER
Long Term.........EER
Aviation..........MJ
AREA FORECAST DISCUSSION
NWS CARIBOU ME
859 PM EDT FRI MAR 25 2016
.SYNOPSIS...
LOW PRESSURE WILL MOVE INTO NEW BRUNSWICK TONIGHT. HIGH PRESSURE
WILL BUILD ACROSS THE REGION SATURDAY...AND THEN MOVE SLOWLY EAST
SUNDAY. LOW PRESSURE WILL PASS SOUTH OF THE AREA MONDAY NIGHT.
&&
.NEAR TERM /THROUGH SATURDAY/...
9 PM UPDATE...
QUICK UPDATE TO BOOST CLD CV OVRNGT AND UNDER LOW CLDS, ESPECIALLY
THOSE WITH OB,S REPORTING VSBY RESTRICTIONS HV ADDED IN PATCHY
FRZG DRIZZLE. -FZDZ OCCURRING AT THE OFFICE AND EXPECT THAT THIS
IS OCCURRING ELSEWHERE AS WELL EVEN THO RETURNS ARE WELL UNDER
RADAR BEAM.
PREVIOUS DISCUSSION...
STAYED WITH THE HRRR 3KM AND GEM MODEL BLEND FOR PRECIP AND TEMPS
FOR THIS PACKAGE. ADDITIONAL ONE TENTH OF AN INCH OF ICE EXPECTED
ACROSS THE FAR NORTH.
THE ICING THREAT WILL END BY EARLY EVENING AS LOW PRES PULLS
TOWARD NEW BRUNSWICK W/SOME SNOW ON THE BACKSIDE AS COLD AIR MOVES
IN AT MID LEVELS. LLVLS WILL COOL DOWN OVERNIGHT AS THE UPPER TROF
SWINGS ACROSS THE REGION. NNW WINDS WILL PICK UP THIS EVENING AS
THE LOW MOVES INTO NEW BRUNSWICK W/SOME GUSTS TO 20 MPH. ANY
ADDITIONAL SNOW WILL BE NO MORE THAN 1/2 INCH. TEMPS WILL FALL
BACK W/SOME CLEARING AFTER MIDNIGHT AS READINGS HIT THE MID AND
UPPER TEENS ACROSS THE NORTH AND WEST W/LOW TO MID 20S ELSEWHERE.
THIS COULD LEAD TO SOME RE-FREEZING OF SURFACES OVERNIGHT.
HIGH PRES IS FORECAST TO SLIDE ACROSS THE REGION FROM QUEBEC ON
SATURDAY. THERE WILL BE SUNSHINE TO ALLOW FOR SOME MELTING, BUT IT
LOOKS AS THOUGH TEMPS WILL BE AROUND NORMAL FOR LATE MARCH. THIS
BEING BASED ON THE ORIENTATION OF THE HIGH AND A ZONAL FLOW ALOFT.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
SATURDAY NIGHT RETURN FLOW OFF THE GULF OF MAINE BECOMES
ESTABLISHED WITH THE POSSIBILITY OF A DEEP LOW LEVEL STRATUS LAYER
MOVING ON-SHORE DURING THE DAY ON SUNDAY.THIS COULD LEAD TO SOME
PATCHY DRIZZLE ON THE COAST AND MAYBE SOME LIGHT FREEZING DRIZZLE
BY SUNDAY NIGHT. CHANCE OF ICE PELLETS/FREEZING RAIN AND FREEZING
DRIZZLE INCREASE TOWARDS MONDAY MORNING AS NEXT WEATHER MAKER
BEGINS TO PUSH INTO THE STATE. A SAINT LAWRENCE VALLEY SURFACE LOW
IS EXPECTED TO TRANSFER ITS ENERGY TO A LOW DEVELOPING OVER
SOUTHERN NEW ENGLAND DURING THE DAY ON MONDAY. LOW LEVEL
TEMPERATES ARE EXPECTED TO RISE ABOVE FREEZING WITH RAIN SHOWERS
EXPECTED MONDAY MORNING. STILL SOME SPREAD IN THE MODELS WITH THE
STRENGTH OF THE DEVELOPING COASTAL LOW...WHICH COULD SUBSTANTIALLY
INCREASE THE RAIN MONDAY AFTERNOON AND WIND SPEEDS. THE GFS SEEMS
TO BE AN OUTLIER WITH A WEAK COASTAL LOW BUT THE SREF/NAM/EC/CMC
ALL HAVE THE COASTAL LOW BECOMING THE PRIMARY DURING THE DAY ON
MONDAY. WILL HAVE TO WATCH THIS OVER THE NEXT FEW DAYS FOR A
SUBSTANTIAL INCREASE IN THE QPF FORECAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE ALOFT ALONG THE EAST COAST SUNDAY NIGHT GIVES WAY TO
AN APPROACHING UPPER TROUGH MONDAY AND MONDAY NIGHT. A COLD FRONT
IS EXPECTED TO BRING RAIN AND WET SNOW MONDAY INTO MONDAY NIGHT. THE
12Z EC AND TO A LESSER EXTENT THE CANADIAN SUGGEST A WET SNOW EVENT
ACROSS NORTHWEST MAINE WITH A RAPIDLY DEEPENING COASTAL LOW ALONG
THE FRONTAL BOUNDARY.
IT WILL BE ABOVE 10 DEGREES COLDER ON TUESDAY IN NORTHWEST FLOW
ALOFT ON TUESDAY. THERE MAY BE INSTABILITY SNOW SHOWERS ACROSS THE
CROWN OF MAINE.
HIGH PRESSURE ALOFT BUILDS IN FOR WEDNESDAY AND THURSDAY. IT SHOULD
BE MUCH WARMER ACROSS DOWNEAST AND CENTRAL MAINE. NOT SO SURE
ABOUT NORTHERN MAINE AT THE TOP OF THE RIDGE AXIS. A STRONG COLD
FRONT IS FORECAST TO SWING THROUGH LATE IN THE FORECAST PERIOD
WITH A CHANCE OF SHOWERS.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: IFR RESTRICTIONS EXPECTED FOR CAR, PQI AND HUL THROUGH
AROUND 05Z SAT LIFTING TO LOW MVFR BY 12Z. MVFR CIGS AT FVE WILL
BECOME VFR BY 12Z. IFR CIGS AT BGR AND BHB HAVE SCATTERED OUT TO
LOW MVFR OR VFR. EXPECT THIS WILL REMAIN THE CASE THROUGH THE
OVERNIGHT. VFR ALL TERMINALS SATURDAY AS HIGH PRESSURE BUILDS IN
FROM QUEBEC.
SHORT TERM: LOW LEVEL STRATUS LAYER EXPECTED BY SUNDAY WHICH
COULD LEAD TO SOME IFR CEILINGS. CHANCE FOR SOME LIGHT FREEZING
RAIN ACROSS THE NORTHERN TAF TERMINALS LATE SUNDAY NIGHT INTO
MONDAY MORNING. LOW CEILINGS AND VISIBILITY EXPECTED TO CONTINUE
THROUGH THE DAY ON MONDAY IN RAIN.
&&
.MARINE...
NEAR TERM: CANCELLED SCA AS SEAS ARE BELOW 5 FEET AND WINDS ARE
LIGHT OUT OF THE W. SEAS WILL BUILD TO AROUND 5 FEET ON SATURDAY
AND WIND GUST WILL APPROACH SCA CRITERIA SO HAVE RE-ISSUED FOR
SAT.
SHORT TERM: HIGH PRESSURE OVER THE WATERS ON SUNDAY WITH A SOUTHERLY
RETURN FLOW DEVELOPING. WINDS AND SEAS WILL STAY BELOW SCA. WE ARE
WATCHING FOR A POSSIBLE GULF OF MAINE LOW PRESSURE DEVELOPING ON
MONDAY...CONFIDENCE IS STILL LOW AT THIS TIME ON THIS STORM.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 6 PM EDT SATURDAY FOR ANZ050-
051.
&&
$$
NEAR TERM...FARRAR/HEWITT
SHORT TERM...DUMONT
LONG TERM...OKULSKI
AVIATION...FARRAR/HEWITT/DUMONT
MARINE...FARRAR/HEWITT/DUMONT
AREA FORECAST DISCUSSION
NWS CARIBOU ME
805 PM EDT FRI MAR 25 2016
.SYNOPSIS...
LOW PRESSURE WILL MOVE INTO NEW BRUNSWICK TONIGHT. HIGH PRESSURE
WILL BUILD ACROSS THE REGION SATURDAY...AND THEN MOVE SLOWLY EAST
SUNDAY. LOW PRESSURE WILL PASS SOUTH OF THE AREA MONDAY NIGHT.
&&
.NEAR TERM /THROUGH SATURDAY/...
8 PM UPDATE...
WK LOPRES IS FILLING WHILE TRAVERSING THE STATE THIS EVNG IN THE
VICINITY OF KATAHDIN. WIND OVR ERN ZONES ARE FM THE EAST WHILE
RMNDR OF AREA EXPERIENCING NRLY WINDS. EXPECT THIS LOW LOW WL
CONT TO FILL LVG BROAD NRLY FLOW ACRS THE ENTIRE CWA. THIS WL PULL
IN LWR DWPTS AND ALLOW CLDS TO SLOWLY SCATTER OUT TONIGHT. CONCERN
IS THAT LOW CLDS OVR QUEBEC ARE A RESULT OF MOISTURE BEING
TRAPPED UNDER INVERSION AND MAY BE CLEARING SKIES TOO QUICKLY. IF
THIS HOLDS TRUE WL ADJUST SKIES AND TEMPS WITH NEXT UPDATE. FOR
NOW HV JUST MASSAGED HRLY T/TD GRIDS TO CURRENT OBS. PCPN HAS
EXITED MOST OF CWA ON TIME WITH LINGERING RAIN LOCATED ACRS
DOWNEAST AND PULLING EAST QUICKLY AND SHUD EXIT AREA IN THE NEXT
HR. NOT SEEING ANY EVIDENCE OF FOG IN OBS OR WEBCAMS ACRS
DOWNEAST SO HV RMVD AREAS OF FOG TONIGHT. NO OTHER CHGS NEEDED
WITH THIS UPDATE.
PREVIOUS DISCUSSION...
STAYED WITH THE HRRR 3KM AND GEM MODEL BLEND FOR PRECIP AND TEMPS
FOR THIS PACKAGE. ADDITIONAL ONE TENTH OF AN INCH OF ICE EXPECTED
ACROSS THE FAR NORTH.
THE ICING THREAT WILL END BY EARLY EVENING AS LOW PRES PULLS
TOWARD NEW BRUNSWICK W/SOME SNOW ON THE BACKSIDE AS COLD AIR MOVES
IN AT MID LEVELS. LLVLS WILL COOL DOWN OVERNIGHT AS THE UPPER TROF
SWINGS ACROSS THE REGION. NNW WINDS WILL PICK UP THIS EVENING AS
THE LOW MOVES INTO NEW BRUNSWICK W/SOME GUSTS TO 20 MPH. ANY
ADDITIONAL SNOW WILL BE NO MORE THAN 1/2 INCH. TEMPS WILL FALL
BACK W/SOME CLEARING AFTER MIDNIGHT AS READINGS HIT THE MID AND
UPPER TEENS ACROSS THE NORTH AND WEST W/LOW TO MID 20S ELSEWHERE.
THIS COULD LEAD TO SOME RE-FREEZING OF SURFACES OVERNIGHT.
HIGH PRES IS FORECAST TO SLIDE ACROSS THE REGION FROM QUEBEC ON
SATURDAY. THERE WILL BE SUNSHINE TO ALLOW FOR SOME MELTING, BUT IT
LOOKS AS THOUGH TEMPS WILL BE AROUND NORMAL FOR LATE MARCH. THIS
BEING BASED ON THE ORIENTATION OF THE HIGH AND A ZONAL FLOW ALOFT.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
SATURDAY NIGHT RETURN FLOW OFF THE GULF OF MAINE BECOMES
ESTABLISHED WITH THE POSSIBILITY OF A DEEP LOW LEVEL STRATUS LAYER
MOVING ON-SHORE DURING THE DAY ON SUNDAY.THIS COULD LEAD TO SOME
PATCHY DRIZZLE ON THE COAST AND MAYBE SOME LIGHT FREEZING DRIZZLE
BY SUNDAY NIGHT. CHANCE OF ICE PELLETS/FREEZING RAIN AND FREEZING
DRIZZLE INCREASE TOWARDS MONDAY MORNING AS NEXT WEATHER MAKER
BEGINS TO PUSH INTO THE STATE. A SAINT LAWRENCE VALLEY SURFACE LOW
IS EXPECTED TO TRANSFER ITS ENERGY TO A LOW DEVELOPING OVER
SOUTHERN NEW ENGLAND DURING THE DAY ON MONDAY. LOW LEVEL
TEMPERATES ARE EXPECTED TO RISE ABOVE FREEZING WITH RAIN SHOWERS
EXPECTED MONDAY MORNING. STILL SOME SPREAD IN THE MODELS WITH THE
STRENGTH OF THE DEVELOPING COASTAL LOW...WHICH COULD SUBSTANTIALLY
INCREASE THE RAIN MONDAY AFTERNOON AND WIND SPEEDS. THE GFS SEEMS
TO BE AN OUTLIER WITH A WEAK COASTAL LOW BUT THE SREF/NAM/EC/CMC
ALL HAVE THE COASTAL LOW BECOMING THE PRIMARY DURING THE DAY ON
MONDAY. WILL HAVE TO WATCH THIS OVER THE NEXT FEW DAYS FOR A
SUBSTANTIAL INCREASE IN THE QPF FORECAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE ALOFT ALONG THE EAST COAST SUNDAY NIGHT GIVES WAY TO
AN APPROACHING UPPER TROUGH MONDAY AND MONDAY NIGHT. A COLD FRONT
IS EXPECTED TO BRING RAIN AND WET SNOW MONDAY INTO MONDAY NIGHT. THE
12Z EC AND TO A LESSER EXTENT THE CANADIAN SUGGEST A WET SNOW EVENT
ACROSS NORTHWEST MAINE WITH A RAPIDLY DEEPENING COASTAL LOW ALONG
THE FRONTAL BOUNDARY.
IT WILL BE ABOVE 10 DEGREES COLDER ON TUESDAY IN NORTHWEST FLOW
ALOFT ON TUESDAY. THERE MAY BE INSTABILITY SNOW SHOWERS ACROSS THE
CROWN OF MAINE.
HIGH PRESSURE ALOFT BUILDS IN FOR WEDNESDAY AND THURSDAY. IT SHOULD
BE MUCH WARMER ACROSS DOWNEAST AND CENTRAL MAINE. NOT SO SURE
ABOUT NORTHERN MAINE AT THE TOP OF THE RIDGE AXIS. A STRONG COLD
FRONT IS FORECAST TO SWING THROUGH LATE IN THE FORECAST PERIOD
WITH A CHANCE OF SHOWERS.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: IFR RESTRICTIONS EXPECTED FOR CAR, PQI AND HUL THROUGH
AROUND 05Z SAT LIFTING TO LOW MVFR BY 12Z. MVFR CIGS AT FVE WILL
BECOME VFR BY 12Z. IFR CIGS AT BGR AND BHB HAVE SCATTERED OUT TO
LOW MVFR OR VFR. EXPECT THIS WILL REMAIN THE CASE THROUGH THE
OVERNIGHT. VFR ALL TERMINALS SATURDAY AS HIGH PRESSURE BUILDS IN
FROM QUEBEC.
SHORT TERM: LOW LEVEL STRATUS LAYER EXPECTED BY SUNDAY WHICH
COULD LEAD TO SOME IFR CEILINGS. CHANCE FOR SOME LIGHT FREEZING
RAIN ACROSS THE NORTHERN TAF TERMINALS LATE SUNDAY NIGHT INTO
MONDAY MORNING. LOW CEILINGS AND VISIBILITY EXPECTED TO CONTINUE
THROUGH THE DAY ON MONDAY IN RAIN.
&&
.MARINE...
NEAR TERM: CANCELLED SCA AS SEAS ARE BELOW 5 FEET AND WINDS ARE
LIGHT OUT OF THE W. SEAS WILL BUILD TO AROUND 5 FEET ON SATURDAY
AND WIND GUST WILL APPROACH SCA CRITERIA SO HAVE RE-ISSUED FOR
SAT.
SHORT TERM: HIGH PRESSURE OVER THE WATERS ON SUNDAY WITH A SOUTHERLY
RETURN FLOW DEVELOPING. WINDS AND SEAS WILL STAY BELOW SCA. WE ARE
WATCHING FOR A POSSIBLE GULF OF MAINE LOW PRESSURE DEVELOPING ON
MONDAY...CONFIDENCE IS STILL LOW AT THIS TIME ON THIS STORM.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EDT SATURDAY FOR ANZ052.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ050-051.
&&
$$
NEAR TERM...FARRAR/HEWITT
SHORT TERM...DUMONT
LONG TERM...OKULSKI
AVIATION...FARRAR/HEWITT/DUMONT
MARINE...FARRAR/HEWITT/DUMONT
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1019 AM EDT THU MAR 24 2016
.SYNOPSIS...
HIGH PRESSURE WILL RETREAT TO THE NORTH OF THE AREA TODAY. LOW
PRESSURE WILL PASS ACROSS MAINE FRIDAY AND WILL MOVE INTO THE
CANADIAN MARITIMES FRIDAY NIGHT. HIGH PRESSURE WILL BUILD INTO
NORTHERN NEW ENGLAND SATURDAY AND WILL MOVE SLOWLY EAST OF THE
REGION SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1007 AM UPDATE...ADJUSTED THE HRLY TEMPS TO FIT THE LATEST
CONDITIONS AS WELL AS ADJUSTMENTS TO THE QPF AND SNOW. 13Z SFC
ANALYSIS SHOWED DOUBLE BARREL HIGH PRES OVER THE REGION W/AN
INVERTED TROF NOSING UP INTO SW MAINE. THERE WAS SOME DECENT LLVL
CONVERGENCE SHOWING UP PER THE WIND FIELD. SOME LIGHT SNOW WAS
OCCURRING IN THE VICINITY OF THIS TROF W/FREYBERG MAINE(KIZG)
REPORTING SNOW. MRMS RADAR INDICATED SNOW EXPANDING FURTHER E
TOWARD THE COASTAL REGION AND THIS WAS PICKED UP WELL BY THE
LATEST RUN OF THE HRRR 3KM AND NAM12. ADJUSTED THE POPS UP FOR THE
COASTAL REGIONS INTO EARLY AFTERNOON. THERE COULD BE A FEW TENTHS
OF ACCUMULATION W/THIS BAND. THE BAND LOOKS LIKE IT DISSIPATES AS
IT LIFTS NORTH IN THE EARLY AFTERNOON AS IT RUNS INTO MUCH DRIER
AIR.
PREVIOUS DISCUSSION...
HIGH PRESSURE WILL MOVE NORTHEAST TODAY. AS IT DOES SO, CLOUDS
WILL INCREASE IN ADVANCE OF LOW PRESSURE APPROACHING FROM THE
WEST. AS THE LOW TRACKS NORTHEAST LATER TODAY, EXPECT OVERUNNING
PRECIPITATION TO DEVELOP FROM WEST TO EAST THIS AFTERNOON IN
ADVANCE OF AN APPROACHING WARM FRONT. ANY PRECIPITATION THIS
AFTERNOON SHOULD MAINLY BE IN THE FORM OF SNOW. WESTERN AREAS
COULD SEE AROUND AN INCH OF SNOW BY LATE THIS AFTERNOON, OTHERWISE
LITTLE IN THE WAY OF ACCUMULATION IS EXPECTED ACROSS THE AREA.
HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE THE UPPER 20S
NORTH AND AROUND 30 CENTRAL AND DOWNEAST.
LOW PRESSURE WILL CONTINUE TO TRACK NORTHEAST TONIGHT
WITH PRECIPITATION CONTINUING TO EXPAND ACROSS THE REGION IN
ADVANCE OF THE APPROACHING WARM FRONT. EXPECT SNOW TO MIX WITH
AND CHANGE TO SLEET AND FREEZING RAIN FROM SOUTH TO NORTH
OVERNIGHT. A WINTER STORM WARNING HAS BEEN ISSUED FOR NORTHERN
AROOSTOOK COUNTY FOR A COMBINATION OF 4 TO 8 INCHES OF SNOW AND
SLEET AND THE POTENTIAL FOR A QUARTER TO HALF INCH OF ICE. WINTER
WEATHER ADVISORIES HAVE BEEN ISSUED FOR THE REMAINDER OF THE
FORECAST AREA FOR THE COMBINATION OF SNOW CHANGING TO A WINTRY
MIX OVERNIGHT. LOWS TONIGHT WILL RANGE FROM THE MID TO UPPER TEENS
NORTH AND MID TO UPPER 20S CENTRAL AND DOWNEAST.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
LOW PRES ACROSS SOUTHEAST ONTARIO AT 12Z FRI WILL TRACK ACROSS
MAINE FRI PM AND IS EXPECTED TO PASS EAST OF THE AREA INTO THE
MARITIMES FRI EVENING. THERE ARE STILL MODEL DIFFERENCES AS TO THE
TRACK OF THE LOW AND WHETHER IT WILL HAVE A DUAL STRUCTURE WITH
ONE LOW PASSING ACROSS THE STATE WITH A SECONDARY LOW PASSING
ACROSS THE GULF OF MAINE. PLAN TO CONTINUE TO SIDE WITH THE COLDER
SOLUTIONS SUCH AS THE NAM AND ECMWF WHICH WOULD GIVE SEVERAL
INCHES OF SNOW ACROSS THE SAINT JOHN VALLEY AND MUCH OF THE NORTH
WOODS WITH AMOUNTS TO DROP OFF TO ONLY AN INCH OR TWO ACROSS
CENTRAL PORTIONS OF THE CWA FROM DOVER-FOXCROFT TO LINCOLN AND
TOPSFIELD, AND AN INCH OR LESS IN THE GREATER BANGOR REGION. MODEL
SOUNDINGS, ESPECIALLY FROM THE NAM INDICATE A PROLONGED PERIOD OF
SLEET AND FREEZING RAIN FROM GREENVILLE- MILLINOCKET- ORIENT NORTH
WITH THE POTENTIAL FOR SIGNIFICANT SLEET ACCUMULATION AND A
QUARTER TO HALF INCH OF FREEZING RAIN. BASED ON THIS PLAN TO
UPGRADE THE WATCHES TO WARNINGS FOR NORTHERN AROOSTOOK COUNTY AND
WILL ISSUE WINTER WEATHER ADVISORIES FOR ALL ZONES TO THE SOUTH.
ALONG THE COAST, ANY FROZEN PRECIPITATION WILL BE SHORT LIVED AND
WILL CHANGE TO ALL RAIN BEFORE DAYBREAK FRI. ONCE THIS SYSTEM
MOVES EAST DRIER AIR WILL FILTER INTO THE AREA FRI NIGHT AS HIGH
PRESSURE BEGINS TO BUILDS TOWARD THE REGION FROM QUEBEC. THE HIGH
WILL CREST OVER MAINE SATURDAY MAKING FOR A SUNNY DAY WITH A
MORNING BREEZE GIVING WAY TO LIGHT WIND IN THE AFTERNOON. TEMPS
WILL CLIMB INTO THE MID 40S DOWNEAST AND INTO THE MID 30S IN THE
SAINT JOHN VALLEY SAT PM.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
SAT NIGHT AND EASTER SUNDAY ARE SHAPING UP TO BE NICE AS HIGH
PRES SLOWLY RETREATS TO THE EAST OF THE AREA. IT WILL BE DRY AND
CLEAR TO PARTLY CLOUDY WITH SOME INCREASE IN CLOUDS IN THE
AFTERNOON. TEMPERATURES WILL BE SEASONABLE WITH HIGHS NEAR 40
DEGREES IN THE CARIBOU/PRESQUE ISLE AREAS AND FROM 45 TO 50
DEGREES DOWNEAST. MODEL UNCERTAINTY IS AGAIN INTRODUCED EARLY
NEXT WEEK. THE OPERATIONAL GFS TAKES DUAL AREAS OF LOW PRES NORTH
AND SOUTH OF THE REGION MONDAY SPLITTING THE AREA AND SPARING ANY
HEAVY PRECIPITATION. THE ECMWF TAKES A DEEPER SFC LOW ACROSS THE
GULF OF MAINE LATE MON NIGHT AND TUE MORNING WITH HEAVY
PRECIPITATION MOVING ACROSS THE AREA, ESPECIALLY CENTRAL AND
DOWNEAST AREAS WITH ENOUGH COLD AIR FOR FROZEN PRECIPITATION
ACROSS NORTHERN TIER OF THE CWA. THERE IS STILL A LOT OF SPREAD IN
BOTH THE 00Z GFS AND 12Z/23RD ECMWF ENSEMBLES AND FORECAST
CONFIDENCE REMAINS LOW. ONCE THIS SYSTEM MOVES THROUGH HIGH
PRESSURE BUILDS INTO THE REGION FROM THE MIDDLE OF NEXT WEEK WITH
DRY AND SEASONABLE WEATHER.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR CONDITIONS THIS MORNING WILL GRADUALLY GIVE WAY TO
MVFR/IFR CONDITIONS IN DEVELOPING SNOW. EXPECT IFR/LIFR CONDITIONS
IN WINTRY PRECIPITATION TONIGHT.
SHORT TERM: IFR AND AT TIMES VLIFR FRI WILL GRADUALLY IMPROVE TO
MVFR BY LATE IN THE DAY FRI OR FRI EVENING WITH CONDITIONS TO
IMPROVE TO VFR OVERNIGHT FRI NIGHT AND CONTINUE SAT THROUGH SUN.
CONDITIONS WILL LOWER TO MVFR SUN NIGHT WITH IFR POSSIBLE BY LATE
MON OR MON NIGHT.
&&
.MARINE...
NEAR TERM: WIND/SEAS WILL GRADUALLY INCREASE TO SMALL CRAFT
ADVISORY LEVELS TODAY AND CONTINUE TONIGHT. VISIBILITY WILL
DECREASE TO 1 TO 3 NM IN PRECIPITATION AND PATCHY FOG.
SHORT TERM: A SMALL CRAFT ADVISORY IS IN EFFECT FOR FRIDAY AND THERE
IS STILL SOME POTENTIAL THAT A FEW WIND GUSTS COULD APPROACH LOW END
GALES. THE WIND WILL DIMINISH AND THE SEAS SUBSIDE TO BELOW
SMALL CRAFT ADVISORY LEVELS BY SAT MORNING ON THE INTRA-COASTAL
WATERS,BUT PROBABLY NOT UNTIL SAT EVENING ON THE COASTAL WATERS.
ONCE THE WIND DIMINISHES AND THE SEAS SUBSIDE CONDITIONS WILL
REMAIN BELOW SCA LEVELS THE REMAINDER OF THE WEEKEND.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING FROM 6 PM THIS EVENING TO 4 PM EDT FRIDAY
FOR MEZ001-002.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT
FRIDAY FOR MEZ003>006-010-011-031-032.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 8 AM EDT
FRIDAY FOR MEZ015>017.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 5 AM EDT
FRIDAY FOR MEZ029-030.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT FRIDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
325 PM EDT THU MAR 24 2016
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 325 PM EDT THU MAR 24 2016
LOW PRESSURE WILL MOVE EAST OF LOWER MICHIGAN THIS EVENING WITH
RAIN CHANGING TO SNOW AND THEN TAPERING OFF TO SNOW SHOWERS AFTER
MIDNIGHT. HIGH PRESSURE WILL MOVE IN AND PROVIDE FAIR WEATHER FOR
FRIDAY AND SATURDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 325 PM EDT THU MAR 24 2016
WE WILL LET THE WINTER STORM WARNING CONTINUE AS PRECIPITATION
CONTINUES ACROSS THE WARNING AREA WITH TEMPERATURES AROUND
FREEZING. WE DO NOT EXPECT MUCH ADDITIONAL ICING...BUT WINDS
GUSTING TO 30 MPH AND ICE COVERED TREES WILL CONTINUE TO CAUSE
POWER OUTAGES.
ANOTHER THING TO WATCH FOR WILL BE WINDS GUSTING OVER 40 MPH INTO
EARLY EVENING ACROSS THE SOUTHERN TIER AS A LINE OF LOW TOPPED
CONVECTION MOVES THROUGH THERE.
THE SFC LOW WILL TRACK OFF TO THE EAST OF THE FORECAST AREA THIS
EVENING WITH THE HRRR CONSISTENT WITH THE OTHER MODEL GUIDANCE IN
BRINGING A BAND OF DEFORMATION AXIS SNOW ACROSS THE CENTRAL AND
NORTHERN ZONES. THIS COULD PUT DOWN A QUICK COATING OF SNOW ON
THE ROADS AFTER DARK AS TEMPERATURES DROP BLO FREEZING.
ONCE THAT GOES BY...DRYING AND SUBSIDENCE MOVES IN WITH ANY SNOW
SHOWERS ENDING BY 12Z FRIDAY. FAIR AND COOL WEATHER ON FRIDAY INTO
SATURDAY. A WEAK NORTHERN STREAM LOW IS APPROACHING SATURDAY NIGHT
WITH LIGHT RAIN OR MIX ACROSS THE NORTH.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 325 PM EDT THU MAR 24 2016
WE ARE MONITORING TWO SYSTEMS IN THE LONG TERM PORTION OF THE FCST.
ONE IS AT THE BEGINNING OF THE PERIOD ON SUN-MON. THE OTHER IS AT
THE END OF THE PERIOD FOR LATE WED-THU.
THE TREND OVER THE PAST DAY IS FOR DIMINISHING PCPN CHCS FOR THE
SYSTEM FOR SUN-MON. THIS TREND IS THE RESULT OF MORE SEPARATION OF
THE SYSTEMS FROM SAT THROUGH SUN. WE WILL SEE THE FRONT FROM THE SAT
SYSTEM BE FURTHER SOUTH OF THE AREA AS THE WAVE TRIES TO MOVE ALONG
THE FRONT ON SUN-MON. THIS LOOKS TO KEEP PCPN MAINLY SOUTH OF THE
AREA. WE HAVE KEPT RAIN CHCS IN THE FCST INTO MON...BUT HAVE LOWERED
THEM A BIT. SOME SNOW COULD MIX IN ON THE BACKSIDE OF IT AS THERE IS
POTENTIAL OF ENOUGH COOLER AIR MOVING IN BEHIND IT.
THE PERIOD FROM MON NIGHT THROUGH TUE NIGHT LOOKS TO BE DRY WITH
MODERATING TEMPS. WE WILL SEE A NICE AMPLITUDE RIDGE MOVE ACROSS
THE AREA BETWEEN LOWS TO OUR EAST AND WEST.
RAIN CHANCES WILL INCREASE BEGINNING ON WED AND BECOME MORE LIKELY
BY THU. THE STRONG UPPER LOW EXPECTED TO TAKE SHAPE ACROSS THE WRN
U.S. WILL START TO EJECT SHORT WAVES TO THE NE TOWARD THE STATE. THE
INITIAL WAVE EJECTING INTO THE AREA ON WED WILL NOT HAVE A LOT OF
MOISTURE TO WORK WITH. THIS SHOULD CHANGE BY THU AS BETTER MOISTURE
WILL HAVE MOVED FURTHER NORTH AHEAD OF SUBSEQUENT WAVES. WE SHOULD
SEE FAIRLY MILD TEMPS WELL INTO THE 50S AND APPROACHING 60 BEING
OUT AHEAD OF THE MAIN SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 130 PM EDT THU MAR 24 2016
THE MAJORITY OF THE AREA IS SHROUDED BY IFR-LIFR EARLY THIS
AFTERNOON WITH ALL RAIN AT THE TERMINALS. WE EXPECT THESE
CONDITIONS TO HOLD UNTIL ABOUT 21-22Z WHEN A TEMPORARY LULL IN THE
PCPN WILL MOVE IN. CONDITIONS WILL LIKELY HOLD IN THE IFR
CATEGORY...EXCEPT FOR THE I-94 TERMINALS WHICH COULD SNEAK UP TO
MVFR IN THE WARMER PART OF THE SYSTEM. SOME STORMS CURRENTLY IN
ERN ILLINOIS WILL POTENTIALLY AFFECT THE I-94 TERMINALS FOR THE
NEXT 3-4 HRS.
AFTER THE LULL...WE WILL SEE THE TAIL END OF THE SYSTEM MOVE
THROUGH MAINLY KGRR AND KMKG IN THE FORM OF SOME LIGHT RAIN
CHANGING TO LIGHT SNOW. THIS WILL BE POSSIBLE FOR 2-3 HRS BEFORE
IT WOULD MOVE OUT.
CONDITIONS WILL THEN GRADUALLY IMPROVE WITH CIGS COMING UP TO VFR
TOWARD 14Z OR SO ON FRI.
&&
.MARINE...
ISSUED AT 325 PM EDT THU MAR 24 2016
SMALL CRAFT ADVISORY CONTINUES THROUGH FRIDAY MORNING THEN
CONDITIONS WILL BE IMPROVING ON FRIDAY AS HIGH PRESSURE WITH
LIGHTER WINDS MOVES IN.
&&
.HYDROLOGY...
ISSUED AT 325 PM EDT WED MAR 23 2016
WIDESPREAD PRECIPITATION CONTINUED THIS AFTERNOON ACROSS ALL OF
LOWER MICHIGAN. 24 HOUR TOTALS OF AROUND 1 INCH ARE EXPECTED BY 8
AM FRIDAY. RIVER RISES ARE EXPECTED AREA WIDE IN THE KALAMAZOO...
GRAND... AND MUSKEGON RIVER BASINS. NUISANCE FLOODING WILL BE COMMON
OVER THE NEXT WEEK IN LOWLAND AREAS ADJACENT TO RIVER BANKS. MORE
IMPACTFUL MINOR FLOODING ALSO CANNOT BE RULED OUT LATE IN THE
WEEKEND INTO NEXT WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING UNTIL 8 PM EDT THIS EVENING FOR MIZ037>040-
043>046-051-052.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EDT FRIDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...EBW
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
400 AM EDT THU MAR 24 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 528 PM EDT WED MAR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID LEVEL LOW MOVING OUT
OVER WRN KS IN THE SRN STREAM. TO THE N IN THE NRN STREAM...BROAD
TROFFING COVERS MUCH OF CANADA. IN THE CONFLUENCE BTWN THIS NRN
TROFFING AND RIDGING OUT AHEAD OF THE KS LOW...UPPER JET RUNNING
FROM JUST N OF LAKE SUPERIOR TO NRN NEW ENGLAND IS STRENGTHENING.
INCREASING UPPER DIVERGENCE ASSOCIATED WITH THE RIGHT ENTRANCE OF
THE JET IS AIDING PCPN EXPANSION WELL TO THE N OF A NEARLY
STATIONARY SFC FRONT EXTENDING FROM SFC LOW IN NCNTRL KS TO LAKE
ERIE. CLOSER TO HOME...A FEW STRATOCU DEVELOPED IN NE WIND UPSLOPE
AREAS OFF LAKE SUPERIOR EARLIER TODAY. OTHERWISE...HIGH CLOUDS HAVE
BEEN INCREASING AND THICKENING TODAY AFTER MORNING SUNSHINE.
FCST TONIGHT/THU WILL REVOLVE AROUND EVOLUTION OF WINTER STORM
CURRENTLY OVER THE PLAINS. MODELS ARE IN GOOD AGREEMENT SHOWING THE
MID LEVEL LOW OVER KS GRADUALLY TRANSITIONING TO AN OPEN WAVE AS IT
MOVES INTO THE GREAT LAKES REGION LATE THU. MEANWHILE...ASSOCIATED
SFC LOW PRES WILL TRACK FROM NE KS TO SRN LWR MI THU AFTN. INITIAL
BAND OF SNOW CURRENTLY LIFTING TOWARD UPPER MI IS BEING DRIVEN
LARGELY BY AFOREMENTIONED RIGHT ENTRANCE OF UPPER JET AND RESULTING
STRENGTHENING OF LOW/MID LEVEL FGEN AND ISENTROPIC ASCENT. ALTHOUGH
SNOW IS CURRENTLY DEVELOPING/INTENSIFYING WHILE SLOWLY LIFTING N THRU
WI...IT WILL ENCOUNTER VERY DRY AIR AT THE LOWER LEVELS THAT WILL
CONTINUE TO ADVECT S AND W FROM HIGH PRES OVER ONTARIO. SFC DWPTS
HAVE BEEN DOWN INTO THE SINGLE DIGITS ACROSS PORTIONS OF UPPER MI
THIS AFTN AND ARE IN THE NEGATIVE SINGLE DIGITS IN ONTARIO. WITH ONLY
A SLIGHT NORTHWARD SHIFT OF FGEN/ISENTROPIC ASCENT TONIGHT... THE
APPROACHING SNOW IN WI WILL INCREASINGLY STRUGGLE TO MOVE N INTO
UPPER MI AS ADVECTION OF LOW-LEVEL DRY AIR ERODES THE NRN PORTION OF
THE PCPN SHIELD. ALL AVBL HIGH RES MODEL GUIDANCE...INCLUDING HOURLY
RAP RUNS TODAY AND 18Z NAM...SHOW PCPN HAVING TROUBLE LIFTING MUCH
FARTHER THAN FAR SCNTRL UPPER MI TONIGHT WITH NORTHWARD EXTENT FROM
ROUGHLY JUST N OF IRON MOUNTAIN TO JUST N OF MANSTIQUE BY 12Z THU.
DURING THU MORNING...DEFORMATION SNOW SHIELD...WHICH IS CURRENTLY
PRODUCING CONSIDERABLE LIGHTNING/TSSN ACROSS PORTIONS OF
NEBRASKA...WILL SHIFT INTO THE UPPER GREAT LAKES IN A WEAKENING
STATE. AS THIS OCCURS...SNOW SHOULD EXPAND INTO PORTIONS OF NCTNRL
AND NE UPPER MI. SNOW WILL THEN DIMINISH/END STEADILY FROM W TO E
DURING THE AFTN.
FOR THIS EVENT...DO NOT EXPECT ANY SNOW TO FALL FROM IRONWOOD TO
L`ANSE INTO THE KEWEENAW. IT`S QUESTIONABLE WHETHER ANY SNOW WILL
REACH MARQUETTE. TO THE S AND E...EXPECT A SIGNIFICANT GRADIENT OF
SNOWFALL FROM N TO S WITH WITH AMOUNTS RANGING FROM AROUND 1 INCH
NEAR LAKE SUPERIOR TO ABOUT A FOOT IN THE CITY OF MENOMINEE. THE NRN
EDGE OF THE SNOW WILL BE THE MOST DIFFICULT CHALLENGE AS DRY AIR
CONTNUALLY EATS AWAY AT SNOW LIFTING INTO THE AREA UNDER WEAKENING
FORCING. WOULD NOT BE SURPRISED IF THE NRN EXTENT OF SNOWFALL
REFLECTED IN THIS FCST DOES NOT OCCUR. HAVE ADDED DICKINSON/NRN
SCHOOLCRAFT/LUCE COUNTIES TO ADVY...THOUGH IT WILL ONLY BE THE SRN
PARTS OF THOSE COUNTIES THAT WILL REACH THE LOW SLR ADVY CRITERIA OF
AT LEAST 2-4 INCHES OF SNOW ACCUMULATION. FAR SRN PARTS OF DELTA AND
SCHOOLCRAFT COUNTIES MAY SEE STORM TOTAL SNOW UP AROUND 6 INCHES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM EDT THU MAR 24 2016
DRY HI PRES CROSSING THE UPR LKS WL BRING A DRY AND MILDER DAY TO
UPR MI ON FRI. SOME MIXED PCPN...THAT COULD INCLUDE FREEZING RA ON
FRI NGT INTO EARLY SAT...WL RETURN THE FIRST HALF OF THE WEEKEND AS
A LO PRES TROF TRACKS THRU THE CWA. BUT LOOKS LIKE THE BULK OF THIS
PCPN WL FALL AS RA THAT WL TEND TO CHANGE TO SOME SN BEFORE ENDING
EARLY ON SUN AS SOMEWHAT COLDER/DRIER AIR FOLLOWS THE TROF PASSAGE.
THE FIRST COUPLE OF DAYS NEXT WEEK SHOULD THEN BE MAINLY DRY...BUT
ANOTHER CHC OF MAINLY RA WL RETURN MID NEXT WEEK ALONG WITH ABOVE
NORMAL TEMPS.
FRI...A SHRTWV RDG/SFC RDG AXIS WILL SHIFT E THRU THE WRN GREAT LKS.
A SLY FLOW ON THE WRN FLANK OF THE SFC RDG AXIS SHIFTING TO THE E WL
LIFT H85 TEMPS UP TO ABOUT 0C. ALTHOUGH THERE WL BE SOME INCRSG HI
CLDS IN ADVANCE OF A LO PRES TROF APRCHG FM THE W...DAYTIME HEATING
SHOULD LIFT MAX TEMPS WELL INTO THE 40S AWAY FM COOLING OFF THE
GREAT LKS...ESPECIALLY LK MI.
FRI NGT THRU SAT NGT...A LO PRES TROF/COLD FNT ASSOCIATED WITH A
PAIR OF SHRTWVS...ONE IN THE ARCTIC BRANCH FLOW OVER SRN CANADA AND
ANOTHER IN THE POLAR BRANCH FLOW OVER THE CONUS...IS FCST TO DRIFT
SLOWLY ACROSS THE UPR LKS DURING THIS PERIOD. MOST OF THE GUIDANCE
INDICATES PCPN IN ADVANCE OF THE TROF IS FCST TO PUSH INTO THE WRN
CWA BY 06Z SAT WITH INCRSG H85 MSTR ADVECTION LIFTING PWAT UP TO
0.50 INCH INTO THE UPR LKS IN THE SW FLOW AHEAD OF THE TROF AND THEN
OVERSPREAD THE REST OF THE CWA ON SAT. SINCE THE SHRTWVS/DYNAMIC
FORCING WL REMAIN OUT OF PHASE...PCPN AMOUNTS ARE NOT EXPECTED TO BE
HEAVY DESPITE THE RATHER SLUGGISH MOTION OF THE TROF. STILL...MOST
OF THE MODELS GENERATE AT LEAST 0.25 INCH TOTAL PCPN OVER MUCH OF
THE CWA. PCPN SHOULD DIMINISH W-E SAT NGT AND END OVER ALL BUT
PERHAPS THE FAR E BY 12Z SUN FOLLOWING THE PASSAGE OF THE SFC TROF
AND ARRIVAL OF DRYING/DEEP LYR QVECTOR DVGC IN THE WAKE OF PASSING
SHRTWVS. FCST SNDGS/H85-100 THKNS FIELDS SUG THE BULK OF THE PCPN WL
BE MAINLY IN THE FORM OF RA EXCEPT PERHAPS OVER THE WRN CWA. WITH
NOCTURNAL COOLING /ALBEIT LIMITED BY INCRSG CLDS/ AND THE WBLB
EFFECT WITH LINGERING NEAR SFC DRY AIR...FCST SDNGS ALSO HINT AT THE
POTENTIAL FOR SOME FREEZING RA LATE FRI NGT/EARLY SAT MRNG
ESPECIALLY OVER THE INTERIOR CENTRAL...SO ADDED THIS PTYPE INTO THE
FCST. INFLUX OF WARMER AIR/DAYTIME HEATING WL END THIS THREAT BY SAT
AFTN. THE LO PRES TROF/COLD FNT CROSSES THE CWA...PTYPE MAY MIX BACK
WITH MORE SN WITH THE ARRIVAL OF COLDER AIR/DYNAMIC COOLING.
SUN THRU WED...ARRIVAL OF TRAILING SFC RDG AXIS/DRIER AIR BEHIND
DEPARTING LO PRES TROF WL END ANY PCPN THAT MIGHT LINGER OVER THE
ERN CWA ON SUN MRNG. WITH H85 TEMPS ARND -5 TO -7C...EXPECT NEAR
SEASONABLE TEMPS. MEDIUM RANGE GUIDANCE THEN HINTS ANOTHER SHRTWV
EMBEDDED IN THE NW FLOW ALOFT WL IMPACT THE AREA SOMETIME SUN NGT
INTO MON NGT. BUT ANY PCPN IN THE FORM OF SN SHOWERS WITH TEMPS AOB
NORMAL SHOULD BE ON THE LIGHT SIDE GIVEN THE ABSENCE OF ANY MSTR
INFLOW. AS AN UPR RDG/SFC HI PRES BUILDS OVER THE AREA ON TUE...
EXPECT A MOSUNNY DAY. WITH H85 TEMPS FCST TO REBOUND TO ARND 0C...
TEMPS AWAY FM THE COOLING INFLUENCE OF THE LKS SHOULD RISE WELL INTO
THE 40S ON TUE AFTN. AS THE SLY FLOW BTWN THE DEPARTING HI PRES AND
DVLPG LO PRES IN THE PLAINS ADVECTS MOISTER AIR INTO THE UPR LKS ON
WED...SOME PCPN MOST LIKELY IN THE FORM OF RA MAY RETURN BY MID WEEK
ALONG WITH ABOVE NORMAL TEMPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 134 AM EDT THU MAR 24 2016
BEING WELL N OF A WINTER STORM THAT WILL BE TRACKING INTO THE GREAT
LAKES REGION...KIWD/KCMX WILL REMAIN VFR THRU THE FCST PERIOD UNDER
AN E TO NE FEED OF DRY AIR AT THE LOW LEVELS. THE NRN FRINGE OF SNOW
ASSOCIATED WITH THE STORM SYSTEM WILL BRUSH KSAW THU MORNING INTO
THU AFTERNOON. IF SO...VFR CONDITIONS MAY FALL TO MVFR AT THAT TIME.
OTHERWISE...VFR CONDITIONS WILL PREVAIL AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 528 PM EDT WED MAR 23 2016
E TO NE WINDS UP TO 25 TO 30KT ARE EXPECTED TONIGHT INTO THU AS PRES
GRADIENT TIGHTENS OVER THE UPPER LAKES BETWEEN HIGH PRES DRIFTING
ACROSS ONTARIO INTO QUEBEC AND LOW PRES TRACKING FROM THE CENTRAL
PLAINS TO FAR SOUTHERN ONTARIO BY LATE THU EVENING. WINDS WILL
QUICKLY DIMINISH TO 15KT OR LESS FROM W TO E LATE THU AFTN THRU FRI
MORNING AS A HIGH PRES RIDGE ARRIVES. THERE WILL BE SOME INCREASE IN
WINDS LATER FRI INTO SAT AHEAD OF THE NEXT LOW PRES TROF. SOUTHERLY
WINDS OVER THE E HALF OF LAKE SUPERIOR MAY INCREASE INTO THE 15-25KT
RANGE FOR A TIME AHEAD OF THE TROF FRI NIGHT INTO SAT. LIKEWISE...
THERE MAY BE 15-25KT NW WINDS FOR A TIME IN THE WAKE OF THE TROF
PASSAGE LATE SAT/SAT NIGHT. WINDS WILL BECOME LIGHT AGAIN LATER SUN
AS A HIGH PRES RIDGE ARRIVES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR MIZ007-
014-085.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON
FOR MIZ011-013.
WINTER STORM WARNING UNTIL 1 PM CDT THIS AFTERNOON FOR MIZ012.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KC
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
134 AM EDT THU MAR 24 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 528 PM EDT WED MAR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID LEVEL LOW MOVING OUT
OVER WRN KS IN THE SRN STREAM. TO THE N IN THE NRN STREAM...BROAD
TROFFING COVERS MUCH OF CANADA. IN THE CONFLUENCE BTWN THIS NRN
TROFFING AND RIDGING OUT AHEAD OF THE KS LOW...UPPER JET RUNNING
FROM JUST N OF LAKE SUPERIOR TO NRN NEW ENGLAND IS STRENGTHENING.
INCREASING UPPER DIVERGENCE ASSOCIATED WITH THE RIGHT ENTRANCE OF
THE JET IS AIDING PCPN EXPANSION WELL TO THE N OF A NEARLY
STATIONARY SFC FRONT EXTENDING FROM SFC LOW IN NCNTRL KS TO LAKE
ERIE. CLOSER TO HOME...A FEW STRATOCU DEVELOPED IN NE WIND UPSLOPE
AREAS OFF LAKE SUPERIOR EARLIER TODAY. OTHERWISE...HIGH CLOUDS HAVE
BEEN INCREASING AND THICKENING TODAY AFTER MORNING SUNSHINE.
FCST TONIGHT/THU WILL REVOLVE AROUND EVOLUTION OF WINTER STORM
CURRENTLY OVER THE PLAINS. MODELS ARE IN GOOD AGREEMENT SHOWING THE
MID LEVEL LOW OVER KS GRADUALLY TRANSITIONING TO AN OPEN WAVE AS IT
MOVES INTO THE GREAT LAKES REGION LATE THU. MEANWHILE...ASSOCIATED
SFC LOW PRES WILL TRACK FROM NE KS TO SRN LWR MI THU AFTN. INITIAL
BAND OF SNOW CURRENTLY LIFTING TOWARD UPPER MI IS BEING DRIVEN
LARGELY BY AFOREMENTIONED RIGHT ENTRANCE OF UPPER JET AND RESULTING
STRENGTHENING OF LOW/MID LEVEL FGEN AND ISENTROPIC ASCENT. ALTHOUGH
SNOW IS CURRENTLY DEVELOPING/INTENSIFYING WHILE SLOWLY LIFTING N THRU
WI...IT WILL ENCOUNTER VERY DRY AIR AT THE LOWER LEVELS THAT WILL
CONTINUE TO ADVECT S AND W FROM HIGH PRES OVER ONTARIO. SFC DWPTS
HAVE BEEN DOWN INTO THE SINGLE DIGITS ACROSS PORTIONS OF UPPER MI
THIS AFTN AND ARE IN THE NEGATIVE SINGLE DIGITS IN ONTARIO. WITH ONLY
A SLIGHT NORTHWARD SHIFT OF FGEN/ISENTROPIC ASCENT TONIGHT... THE
APPROACHING SNOW IN WI WILL INCREASINGLY STRUGGLE TO MOVE N INTO
UPPER MI AS ADVECTION OF LOW-LEVEL DRY AIR ERODES THE NRN PORTION OF
THE PCPN SHIELD. ALL AVBL HIGH RES MODEL GUIDANCE...INCLUDING HOURLY
RAP RUNS TODAY AND 18Z NAM...SHOW PCPN HAVING TROUBLE LIFTING MUCH
FARTHER THAN FAR SCNTRL UPPER MI TONIGHT WITH NORTHWARD EXTENT FROM
ROUGHLY JUST N OF IRON MOUNTAIN TO JUST N OF MANSTIQUE BY 12Z THU.
DURING THU MORNING...DEFORMATION SNOW SHIELD...WHICH IS CURRENTLY
PRODUCING CONSIDERABLE LIGHTNING/TSSN ACROSS PORTIONS OF
NEBRASKA...WILL SHIFT INTO THE UPPER GREAT LAKES IN A WEAKENING
STATE. AS THIS OCCURS...SNOW SHOULD EXPAND INTO PORTIONS OF NCTNRL
AND NE UPPER MI. SNOW WILL THEN DIMINISH/END STEADILY FROM W TO E
DURING THE AFTN.
FOR THIS EVENT...DO NOT EXPECT ANY SNOW TO FALL FROM IRONWOOD TO
L`ANSE INTO THE KEWEENAW. IT`S QUESTIONABLE WHETHER ANY SNOW WILL
REACH MARQUETTE. TO THE S AND E...EXPECT A SIGNIFICANT GRADIENT OF
SNOWFALL FROM N TO S WITH WITH AMOUNTS RANGING FROM AROUND 1 INCH
NEAR LAKE SUPERIOR TO ABOUT A FOOT IN THE CITY OF MENOMINEE. THE NRN
EDGE OF THE SNOW WILL BE THE MOST DIFFICULT CHALLENGE AS DRY AIR
CONTNUALLY EATS AWAY AT SNOW LIFTING INTO THE AREA UNDER WEAKENING
FORCING. WOULD NOT BE SURPRISED IF THE NRN EXTENT OF SNOWFALL
REFLECTED IN THIS FCST DOES NOT OCCUR. HAVE ADDED DICKINSON/NRN
SCHOOLCRAFT/LUCE COUNTIES TO ADVY...THOUGH IT WILL ONLY BE THE SRN
PARTS OF THOSE COUNTIES THAT WILL REACH THE LOW SLR ADVY CRITERIA OF
AT LEAST 2-4 INCHES OF SNOW ACCUMULATION. FAR SRN PARTS OF DELTA AND
SCHOOLCRAFT COUNTIES MAY SEE STORM TOTAL SNOW UP AROUND 6 INCHES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 516 PM EDT WED MAR 23 2016
MODELS WERE IN GENERAL AGREEMENT THAT TROUGHING OVER THE CNTRL CONUS
WITH THE NRN STREAM DOMINATING THE NRN LAKES...WILL GIVE WAY TO MID
LEVEL RIDGING AS A SRN STREAM TROUGH DIGS INTO THE GREAT BASIN.
THURSDAY NIGHT...AS THE STRONG SHRTWAVE TROUGH LIFT QUICKLY TO THE
NE THROUGH LOWER MI DURING THE EVENING STRONG 700-300 MB QVECTOR DIV
MOVING INTO THE ERN CWA WILL END THE LINGERING SNOW WITH LITTLE
ADDITIONAL ACCUMULATIONS. MID LEVEL AND SFC RIDGING BUILDING INTO
THE AREA OVERNIGHT WILL BRING CLEARING SKIES AND GOOD RADIATIONAL
COOLING CONDITIONS FAVORING TEMPS NEAR THE LOWER END OF
GUIDANCE...ESPECIALLY INLAND WEST HALF.
FRIDAY...SRLY FLOW AND WAA WILL DEVELOP AS THE RIDGE DEPARTS TO THE
EAST. SUNSHINE WILL ALLOW TEMPS TO CLIMB NEAR OR ABOVE SEASONAL
AVERAGES WITH HIGHS IN THE UPER 30S N AND E TO HE LOWER TO MID 40S
OVER THE SW.
FRI NIGHT THROUGH SAT NIGHT...MODELS SHOW PCPN ASSOCIATED WITH MID
LEVEL SHORTWAVE AND SFC TROUGH SPREADING ACROSS UPPER MICHIGAN. WITH
ONLY MODEST DYNAMICS AND MOISTURE INFLOW...GENERALLY LIGHT AMOUNTS
OF AROUND 0.10 INCH OR LESS IS EXPECTED. FCST LOW LEVEL THICKNESS
AND WET-BULB ZERO HEIGHTS SUGGEST THAT THE PCPN MAY FALL AS
RAIN...ESPECIALLY OVER THE SOUTH AND EAST DURING PEAK HEATING
SATURDAY.
SUN-MON...WITH SFC RIDGING AND A DRY AIRMASS OVER THE AREA...EXPECT
LITTLE PCPN DESPITE POTENTIAL FOR WEAK NRN STREAM SHRTWVS TO BRUSH
THE AREA. TEMPS SHOULD REMAIN NEAR SEASONAL AVERAGES.
TUE-WED...MILDER AIR IS EXPECTED TO SPREAD INTO THE REGION WITH A
STRENGTHENING WAA PATTERN AHEAD OF A TROUGH DEVELOPING OVER THE ERN
PLAINS. SOME LIGHT PCPN...MAINLY AS RAIN...MAY SPREAD TOWARD THE
AREA BY WED AS MOISTURE ADVECTION ALSO INCREASES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 134 AM EDT THU MAR 24 2016
BEING WELL N OF A WINTER STORM THAT WILL BE TRACKING INTO THE GREAT
LAKES REGION...KIWD/KCMX WILL REMAIN VFR THRU THE FCST PERIOD UNDER
AN E TO NE FEED OF DRY AIR AT THE LOW LEVELS. THE NRN FRINGE OF SNOW
ASSOCIATED WITH THE STORM SYSTEM WILL BRUSH KSAW THU MORNING INTO
THU AFTERNOON. IF SO...VFR CONDITIONS MAY FALL TO MVFR AT THAT TIME.
OTHERWISE...VFR CONDITIONS WILL PREVAIL AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 528 PM EDT WED MAR 23 2016
E TO NE WINDS UP TO 25 TO 30KT ARE EXPECTED TONIGHT INTO THU AS PRES
GRADIENT TIGHTENS OVER THE UPPER LAKES BETWEEN HIGH PRES DRIFTING
ACROSS ONTARIO INTO QUEBEC AND LOW PRES TRACKING FROM THE CENTRAL
PLAINS TO FAR SOUTHERN ONTARIO BY LATE THU EVENING. WINDS WILL
QUICKLY DIMINISH TO 15KT OR LESS FROM W TO E LATE THU AFTN THRU FRI
MORNING AS A HIGH PRES RIDGE ARRIVES. THERE WILL BE SOME INCREASE IN
WINDS LATER FRI INTO SAT AHEAD OF THE NEXT LOW PRES TROF. SOUTHERLY
WINDS OVER THE E HALF OF LAKE SUPERIOR MAY INCREASE INTO THE 15-25KT
RANGE FOR A TIME AHEAD OF THE TROF FRI NIGHT INTO SAT. LIKEWISE...
THERE MAY BE 15-25KT NW WINDS FOR A TIME IN THE WAKE OF THE TROF
PASSAGE LATE SAT/SAT NIGHT. WINDS WILL BECOME LIGHT AGAIN LATER SUN
AS A HIGH PRES RIDGE ARRIVES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 6 AM THIS MORNING TO 5 PM EDT THIS
AFTERNOON FOR MIZ007-014-085.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ013.
WINTER STORM WARNING UNTIL 1 PM CDT THIS AFTERNOON FOR MIZ012.
WINTER WEATHER ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR MIZ011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1212 AM EDT THU MAR 24 2016
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 327 PM EDT WED MAR 23 2016
LOW PRESSURE WILL TRACK ACROSS SOUTHERN LOWER MICHIGAN TONIGHT
AND THURSDAY AND BRING A WIDE RANGE OF WEATHER. UP TO A FOOT OF
SNOW AND SIGNIFICANT ICING IS POSSIBLE ACROSS THE NORTHERN HALF OF
LOWER MICHIGAN. A MIXTURE OF RAIN...SLEET AND FREEZING RAIN IS
EXPECTED ACROSS CENTRAL LOWER MICHIGAN AND RAIN ACROSS THE SOUTH.
THERE COULD BE A FEW THUNDERSTORMS ACROSS FAR SOUTHERN LOWER
MICHIGAN ON THURSDAY. THE STORM WILL BE TAPERING OFF TO SNOW
SHOWERS THURSDAY NIGHT.
&&
.UPDATE...
ISSUED AT 912 PM EDT WED MAR 23 2016
NO HEADLINE OR FCST CHANGES ARE NECESSARY THIS EVENING. A MIX OF
HEAVY WET SNOW AND FREEZING RAIN WILL CONTINUE ACROSS THE WARNING
AREA OVERNIGHT INTO THURSDAY WITH TOTAL ICE ACCUMULATIONS OF A
QUARTER TO HALF AN INCH AND LOCALLY HIGHER AMOUNTS IN EXCESS OF A
HALF AN INCH POSSIBLE.
TOTAL SNOW ACCUMULATIONS OF 5 TO 9 INCHES ARE ANTICIPATED OUR FAR
NORTHERN FCST AREA WHERE PCPN WILL FALL PREDOMINANTLY IN THE FORM
OF SNOW. THE COMBINATION OF HEAVY WET SNOW AND FREEZING RAIN AND
BREEZY CONDITIONS WILL RESULT IN SCATTERED TO POTENTIALLY NUMEROUS
POWER OUTAGES ACROSS PORTIONS OF THE WARNING AREA.
FURTHER SOUTH FOR THE COUNTIES IN THE ADVISORY A MIX OF RAIN AND
FREEZING RAIN WILL CONTINUE THROUGH THE LATE EVENING HOURS THOUGH
PCPN WILL FALL MORE IN THE FORM OF PLAIN RAIN THAN FZRA. EVEN SO
SOME LIGHT ICING IS POSSIBLE PARTICULARLY ACROSS NORTHERN MKG...
KENT... IONIA AND CLINTON COUNTIES.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 327 PM EDT WED MAR 23 2016
NO SIGNIFICANT CHANGES TO THE FORECAST AS THE 12Z MODEL GUIDANCE
REMAINS IN GOOD AGREEMENT AND THE HRRR SUPPORTS THE GOING FORECAST
FOR EVOLUTION OF P TYPE TONIGHT. WE EXPECT THE NORTHERN TIER TO
SEE THE HIGHEST SNOW AMOUNTS WITH WITH A BAND OF SLEET OR FREEZING
RAIN CUTTING SNOW ACCUMULATIONS SHARPLY TO THE SOUTH.
THE ICING THREAT STILL APPEARS TO BE CENTERED AROUND THE AREA
FROM ALMA TO MT PLEASANT AND WEST TO BIG RAPIDS WHERE A QUARTER TO
HALF INCH OF ICE ACCUM IS POSSIBLE. THE SOUTHERN EDGE OF THE
FREEZING RAIN IS STILL EXPECTED TO BE ALONG OR JUST NORTH OF I-96
TONIGHT.
WE ALSO HAVE TO CONTEND WITH THUNDERSTORM POTENTIAL FOR THE
SOUTHERN BORDER OF THE FORECAST AREA ON THURSDAY AS THERE IS SOME
INSTABILITY THAT IS SFC BASED DURING THE AFTERNOON. WILL CONTINUE
TO HAVE THUNDER IN THE FAR SOUTHERN ZONES.
THE LOW MOVES EAST LATE THURSDAY WITH A NORTH FLOW OF COLDER AIR
CHANGING PRECIP OVER TO SNOW SHOWERS DURING THE EVENING ACROSS THE
ENTIRE FORECAST AREA. A QUICK INCH OR TWO OF SNOW IS POSSIBLE
CROSS MUCH OF THE FORECAST AREA DEPENDING ON HOW THE DEFORMATION
ZONE PIVOTS THROUGH. WINDS GUSTING TO 25 MPH COULD CAUSE PROBLEMS
IF ICE ACCUMULATIONS PERSIST INTO THURSDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 327 PM EDT WED MAR 23 2016
HE LONG TERM PORTION OF THE FCST LOOKS LIKE WE WILL SEE MORE
OCCASIONAL WET WEATHER...AS HAS BEEN THE CASE FOR THE PAST FEW WEEKS.
DRIER WEATHER FROM THE END OF THE SHORT TERM ON FRI WILL REMAIN INTO
AT LEAST THE FIRST PART OF SAT BEFORE PCPN CHCS WILL INCREASE LATER.
A SHORT WAVE ROUNDING THE BASE OF A LONGER WAVE TROUGH ACROSS THE
PLAINS WILL LIFT JUST NW OF THE AREA LATE SAT AND SAT NIGHT. THIS
WILL PUSH A FRONT INTO THE AREA. THE FRONT WILL NOT MAKE IT FAR SE
WITH UPPER WAVE STAYING NW. WE WILL ALSO HAVE ANOTHER WAVE FROM THE
SRN JET LIFT OUT OF THE PLAINS AND GO JUST SOUTH OF THE STATE. RAIN
CHCS WILL BE MUCH BETTER ON SUN WITH THE SRN STREAM WAVE AS IT WILL
DRAW GULF MOISTURE NWD. PCPN LOOKS TO BE MAINLY RAIN THROUGH SUN AS
THE COLDER AIR FROM THE NW GETS HELD UP. PCPN COULD EVENTUALLY
CHANGE OVER TO SOME SNOW AT THE END OF THE EVENT AS SOME COLDER AIR
DOES FINALLY TRY TO MAKE IT IN ON THE BACKSIDE OF THE SYSTEM.
WE SHOULD THEN SEE A BREAK IN THE WEATHER FROM LATER MON THROUGH
TUE/TUE NIGHT. THE UPPER PATTERN OVER NORTH AMERICA WILL BE RATHER
AMPLIFIED WITH THE STRONGER SYSTEM EXITING TO THE EAST...AND ANOTHER
LONG WAVE TROUGH SETTING UP ACROSS THE WRN PORTION OF THE COUNTRY.
WE WILL END UP WITH THE UPPER RIDGE HOLDING IN OVER OUR PORTION OF
THE COUNTRY.
THE THREAT FOR PCPN WILL THEN INCREASE ONCE AGAIN AT THE END OF THE
LONG TERM. THE UPPER RIDGE WILL MOVE FAR ENOUGH EAST THAT WAVES
EJECTING FROM THE WRN TROUGH/LOW WILL START TO IMPACT THE AREA
AROUND WED. THIS COULD END UP GETTING PUSHED BACK OVER TIME AS IS
THE CASE MANY TIMES IN THIS TYPE OF A PATTERN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1212 AM EDT THU MAR 24 2016
POOR AVIATION CONDITIONS ARE EXPECTED THE REMAINDER OF THE NIGHT
AND THROUGH MUCH OF THE DAY ON THURSDAY. IFR CONDITIONS ARE
TRENDING TO LIFR ACROSS THE TAF SITES AT THIS TIME. BY
MORNING...ALL TAF SITES SHOULD BE IN THE LIFR CATEGORY.
PRECIPITATION THE REST OF TONIGHT SHOULD BE LIGHT DRIZZLE OF LIGHT
RAIN AT MOST SITES AND LIGHT FREEZING RAIN AT KMKG.
AFTER 12Z...THE PRECIPITATION SHOULD BE ALL RAIN ON THURSDAY
BEFORE ENDING AS A LITTLE BIT OF LIGHT SNOW OR FLURRIES. CEILINGS
WILL REBOUND THURSDAY EVENING TO MVFR.
&&
.MARINE...
ISSUED AT 327 PM EDT WED MAR 23 2016
SMALL CRAFT ADVISORY WILL CONTINUE THROUGH THURSDAY NIGHT.
CONDITIONS SHOULD IMPROVE BY FRIDAY.
&&
.HYDROLOGY...
ISSUED AT 239 PM EDT WED MAR 23 2016
WIDESPREAD PRECIPITATION AMOUNTS OF 0.75-1.50 INCHES ARE EXPECTED
THROUGH FRIDAY MORNING. RIVER RISES WILL OCCUR... BUT NO SIGNIFICANT
FLOODING IS EXPECTED.
MINOR FLOODING IS CERTAINLY POSSIBLE... MAINLY IN THE FORM OF
NUISANCE FLOODING IN LOWLAND AREAS NEAR RIVER BANKS. AS OF THIS
WRITING... RIVER FLOOD ADVISORIES WERE IN EFFECT FOR THE MAPLE
RIVER AT MAPLE RAPIDS... GRAND RIVER AT IONIA... LOOKING GLASS
RIVER AT EAGLE... AND SYCAMORE CREEK AT HOLT.
ADDITIONAL PRECIPITATION IS EXPECTED SUNDAY INTO SUNDAY
NIGHT...WHICH WILL PROLONG ELEVATED RIVER LEVELS AND COULD RESULT IN
ADDITIONAL MINOR FLOODING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THURSDAY FOR MIZ050-
056>059.
WINTER STORM WARNING UNTIL 8 PM EDT THURSDAY FOR MIZ037>040-
043>046-051-052.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EDT FRIDAY FOR LMZ844>849.
&&
$$
UPDATE...LAURENS
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...NJJ
AVIATION...DUKE
HYDROLOGY...EBW
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS BILLINGS MT
913 PM MDT FRI MAR 25 2016
.UPDATE...
UPSLOPE SNOW SHOWERS CONTINUE ALONG THE NE ASPECTS OF THE
BEARTOOTH ABSAROKAS BUT HAVE DIMINISHED ELSEWHERE AS SHORTWAVE
PUSHES SOUTH INTO WYOMING. PCPN ALONG THE FOOTHILLS WILL TAPER OFF
DURING THE LATE EVENING AND WOULD EXPECT AN INCH OR TWO OF SNOW TO
HAVE FALLEN SINCE LATE AFTERNOON. LOOKING TO OUR EAST...CLEARING
SKIES ALREADY NOTED NEAR FORSYTH...MILES CITY AND BAKER AS DRIER
AIR SPREADS IN FROM THE NORTH. SFC DEW PTS IN OUR EAST HAVE FALLEN
BUT REMAIN IN THE LOWER 20S AS OF 9 PM. GIVEN THERE ARE LINGERING
PATCHES OF SNOW COVER ACROSS OUR EAST FEEL THAT SOME FOG IS A
POSSIBILITY LATER TONIGHT...AS HRRR IS NOW SUGGESTING. BOUNDARY
LAYER MOISTURE WILL REMAIN TRAPPED IN OUR WEST AND CENTRAL PARTS
COURTESY OF LIGHT EASTERLY WINDS...BECOMING LIGHT DRAINAGE LATE
TONIGHT...SO FOG IS A VERY GOOD POSSIBILITY WHEREVER SKIES ARE
ABLE TO CLEAR. HAVE ADDED MENTION OF PATCHY FOG ACROSS MOST OF OUR
LOWER ELEVATIONS FROM 06-15Z. TEMPS TONIGHT WILL BE QUITE CHILLY
WITH LOWS RANGING FROM THE MID TEENS TO MID 20S...COLDEST IN OUR
EAST. HAVE TWEAKED TEMPS UP A BIT IN OUR WEST PER DEW PTS IN THE
UPPER 20S AND WHAT SHOULD BE MORE PERSISTENT CLOUD COVER. JKL
&&
.SHORT TERM...VALID FOR SAT AND SUN...
BROAD UPPER TROUGH HAS SETTLED INTO THE NORTHERN ROCKIES. ONE
SHORTWAVE WAS PULLING OUT OF SOUTHEAST MONTANA THIS AFTERNOON AND
THIS WAS GRADUALLY TAPERING SNOWFALL OFF OVER THE SOUTHEAST. A
STRONGER PIECE OF ENERGY WAS DROPPING INTO SOUTHWEST IDAHO THIS
HOUR. THIS WAVE WAS GENERATING UPSLOPE FLOW OVER WESTERN AND
CENTRAL ZONES. THIS UPSLOPE...COMBINED WITH CYCLONIC FLOW OF THE
TROUGH...WAS PRODUCING SNOW SHOWERS OVER CENTRAL AND WESTERN
ZONES. RADAR COVERAGE WAS GRADUALLY SHIFTING SOUTHWEST. WILL
LINGER HIGH POPS OVER THE FOOTHILLS AND UPSLOPE LOCATIONS OF THE
MOUNTAINS WITH SCATTERED POPS OVER THE PLAINS. WILL HAVE TO WATCH
RED LODGE CLOSELY THIS EVENING. IF A SNOW BAND LINGERS LONGER THAN
EXPECTED...COULD BE AN ADVISORY SITUATION. OPTED TO LEAVE
ACCUMULATION UNDER CRITERIA AS HIGH RESOLUTION MODELS TAPER SHOWER
ACTIVITY OFF QUICKLY BY MID EVENING. WILL ALSO HAVE TO WATCH
CLOSELY FOR FOG FORMATION. COORDINATION WITH OTHER OFFICES LED TO
LEAVING FOG OUT AS HAVE TO WATCH FOR CLOUDS TO CLEAR BEFORE HAVING
A REAL GOOD INDICATION OF FORMATION. GUIDANCE KEEPS FOG OUT OF
MOST LOCATIONS...WITH SOME PATCHY FORMATION IN LOWER VALLEYS.
EVENING CREW WILL TAKE A CLOSE LOOK AT THIS.
NORTHERLY FLOW TAKES OVER FOR TOMORROW. THE FLOW WAS DRIER
DESPITE A SHORTWAVE TROUGH WORKING ACROSS. SOME INSTABILITY
PRESENT BUT WITH LIMITED MOISTURE...WILL KEEP POPS OUT OF THE
FORECAST. RIDGING AND INCREASING DOWNSLOPE FLOW WILL LEAD TO
WARMER TEMPERATURES FOR SUNDAY. THE NEXT SYSTEM TO IMPACT THE AREA
WILL DROP INTO OREGON SUNDAY NIGHT WITH SOUTHWEST FLOW DEVELOPING.
FOR THE FORECAST AREA. HAVE RAISED POPS FOR THE WEST AS MOISTURE
AND SHORTWAVE INFLUENCE INCREASES. THIS WILL SET THE STAGE FOR A
POTENTIALLY MAJOR SPRING STORM SYSTEM FOR EARLY NEXT WEEK AS THE
UPPER LOW DIGS INTO NORTHERN NEVADA. MORE ON THAT IN THE EXTENDED.
TWH
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
SEVERAL ADJUSTMENTS TO THE EXTENDED FORECAST PERIOD...WITH A SLOW
MOVING SPRING STORM SYSTEM PROGGED TO DOMINATE THE PATTERN FROM
MONDAY THROUGH WEDNESDAY. GREATEST CHANGES CENTERED AROUND
INCREASING POPS ACROSS THE REGION THROUGH THIS PERIOD...AND
LOWERING TEMPS SLIGHTLY AS WELL.
A TROF OVER THE WESTERN CONUS FORMS CUT OFF UPPER LEVEL LOW OVER
THE WEEKEND...DEEPENING AND DIGGING SOUTHEAST EARLY NEXT WEEK.
DIFFLUENT SOUTHWEST FLOW BRINGS IMPROVING SNOW POTENTIAL INTO
WESTERN MOUNTAINS AND WESTERN PLAINS. SNOW AND RAIN SHOWERS
SPREAD ACROSS WESTERN ZONES...AS DIFFLUENT FLOW SHIFTS AHEAD OF
APPROACHING LOW. PRECIP CONTINUES TO SPREAD EASTWARD THROUGH
MONDAY NIGHT AND TUESDAY...WITH PRECIP PROGGED TO PERSIST ACROSS
THE REGION THROUGH TUESDAY NIGHT. CURRENTLY IT APPEARS THAT THE
PRECIP SHOULD SWITCH TO SNOW MONDAY NIGHT...AND BE PRIMARILY SNOW
OR RAIN/ SNOW MIX THROUGH WEDNESDAY. ADDITIONALLY...AT THIS TIME
THE BEST PRECIP POTENTIAL LOOKS LIKE TUESDAY AFTERNOON THROUGH TUE
NIGHT ESPECIALLY FOR WESTERN/CENTRAL ZONES AS BEST FORCING AND
LOW-LEVEL NORTH/NORTHEASTERLY FLOW MOVE OVER THE AREA DURING THAT
TIME. QPF AMOUNTS APPEAR TO EXCEED AN INCH IN MOST
LOCATIONS...WITH A CHANCE FOR SIGNIFICANT PORTION OF IT TO FALL AS
SNOW. TIMING VARIES A BIT ON THE SYSTEM EXITING THE REGION...WITH
ECMWF EXITING MORE QUICKLY AND LEAVING MOST OF THE REGION DRY
DURING THE DAY WED.
CURRENTLY THE EXPECTED TEMPS LOOK BORDERLINE FOR SNOW
ACCUMULATION IN THE LOWER ELEVATIONS DURING THE DAYTIME PERIODS.
THEREFORE...ACCUMULATIONS MAY BE LIMITED DUE TO STRONG MARCH SUN
ANGLE. HOWEVER...IF SNOWFALL RATES ARE HIGH...ACCUMULATION ON THE
GROUND COULD OCCUR DURING THE DAY...ESPECIALLY TUESDAY.
THERE APPEARS TO BE A BRIEF PERIOD OF CLEARING WEDNESDAY/
WEDNESDAY NIGHT....DEPENDING ON THE FAVORED MODEL...ALLOWING FOR
OVERNIGHT TEMPERATURES IN TEENS AND 20S ACROSS THE REGION.
ANOTHER WAVE OF ENERGY IS PROGGED TO PUSHING INTO THE AREA FORM
THE NORTH ON THURSDAY...BRINGING ANOTHER SHOT OF SNOW TO THE
REGION. THIS SYSTEM IS A MUCH FASTER MOVING SYSTEM...AND WILL EXIT
THE REGION FRIDAY EVENING/NIGHT. HAVE KEPT POPS LOW FOR THIS
SYSTEM AT THIS TIME...BUT MODELS ARE IN PRETTY GOOD AGREEMENT FOR
THIS WAVE MOVING ACROSS THE AREA. GILSTAD
&&
.AVIATION...
RAIN AND SNOW WILL HUG THE NORTH FACING SLOPES OF THE HIGHER
TERRAIN THROUGH ABOUT 05Z BEFORE DIMINISHING...WITH ASSOCIATED
AREAS OF IFR CONDITIONS. LOW CIGS MAY FOLLOW PCPN THROUGH 08Z BUT
IMPROVE FROM NORTH TO SOUTH LATE. HOWEVER...WE EXPECT TO SEE AREAS
OF FOG DEVELOP AS EARLY AS 09Z...INCLUDING THE AREA FROM KBIL TO
KSHR...AND ESPECIALLY ACROSS EASTERN MONTANA INCLUDING KBHK AND
K97M. MOUNTAINS WILL BE FREQUENTLY OBSCURED OVERNIGHT. BT
&&
.PRELIMINARY POINT TEMP/POPS...
SAT SUN MON TUE WED THU FRI
-----------------------------------------------------------
BIL 023/050 031/059 035/049 033/039 026/038 022/041 027/044
10/U 00/U 24/W 57/S 64/S 23/J 22/W
LVM 021/049 029/054 030/043 025/036 022/035 017/040 024/047
60/B 01/N 56/W 67/S 66/S 23/J 32/W
HDN 019/052 022/061 030/055 031/042 025/042 019/041 022/044
10/U 00/U 12/W 47/O 84/S 24/J 22/W
MLS 021/051 028/062 031/060 035/043 027/042 024/041 024/045
00/U 00/U 02/W 36/O 73/S 23/J 22/W
4BQ 019/047 023/061 028/061 033/044 027/040 021/040 022/043
10/U 00/U 01/B 35/O 75/S 24/J 22/W
BHK 015/044 025/057 028/059 032/041 027/039 022/038 022/039
00/U 00/U 01/N 35/O 75/S 24/J 22/J
SHR 018/046 021/056 027/055 030/039 025/036 014/037 022/043
20/U 00/U 12/W 57/S 76/S 33/J 32/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
607 PM CDT FRI MAR 25 2016
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 316 PM CDT FRI MAR 25 2016
MAIN FORECAST CHALLENGE THROUGH SATURDAY DEALS WITH A COLD FRONT AND
SHORTWAVE PASSAGE FRIDAY NIGHT. MID LEVEL CLOUDINESS HAS BEEN RATHER
THICK THROUGHOUT THE DAY WITH A FEW LIGHT SHOWERS ACROSS FAR
NORTHWEST NEBRASKA... MAINLY CONFINED TO THE PINE RIDGE. WEAK RADAR
ECHOES HAVE BEEN OBSERVED OVER SOUTHWEST NEBRASKA... BUT WITH DEW
POINT DEPRESSIONS AROUND 25F... ONLY RESULT IS VIRGA.
THIS EVENING AND TONIGHT... MID LEVEL FRONTOGENESIS INCREASES AS THE
SHORTWAVE APPROACHES NORTHERN NEBRASKA AND MOISTURE SLOWLY WORKS
TOWARD THE SURFACE. REMOVED MENTION OF SPRINKLES SOUTH OF NEB HWY 2
AS LIFT IN THE LOWER 200HPA DISAPPEARS. THROUGH 06Z... BEST
SATURATION AND LIFT EXIST ACROSS NORTHERN SHERIDAN AND NORTHWEST
CHERRY COUNTIES... SO RETAINED LIKELY POPS FOR A SMALL AREA ALONG
THE SD BORDER. HRRR HINTS AT SOME SHOWER ACTIVITY FARTHER EAST... SO
EXTENDED SCHC POPS SOUTH TOWARD KTIF AND EAST TOWARD KONL. NAM
FORECAST SOUNDINGS INDICATE A SWITCH TO SNOW AT MERRIMAN AROUND 03Z
AND VALENTINE AROUND 05Z. USED A GRADUAL TRANSITION FROM RA TO RASN
TO SN FROM WEST TO EAST.
SNOWFALL WISE... SOUNDINGS AT KVTN SHOW THE BULK OF THE MOISTURE
BELOW 600HPA THROUGH THE NIGHT AND LIFT BELOW 800HPA... WHERE THE
DGZ GENERALLY LINES UP WITH 600-700HPA. TEMPERATURES SLOWLY FALL
FROM THE 30S INTO THE 20S WHICH WILL LIMIT SLR. START AROUND 10:1
FOR 06-12Z AND INCREASE TO NEAR CLIMO... 12-13:1... BY LATE MORNING.
TOTAL ACCUMULATIONS ARE AROUND 1 INCH ALONG AND NORTH OF HWY 20 WEST
OF KVTN AND A DUSTING FROM KAIA TO KONL.
HAVE WINDS PICKING UP QUITE A BIT WITH THE FROPA. NAM INDICATING
850HPA WINDS NEAR 35KTS AND A 1MB/HR PRESSURE CHANGE. MECHANICAL
FORCING WILL BRING MUCH OF THIS TO THE SURFACE AND WILL LIKELY
INHIBIT BOUNDARY LAYER DECOUPLING. STRONG CAA IS EVIDENT WITH 850HPA
TEMPS DROPPING FROM 1C AT KLBF AT 06Z TO NEAR -5C BY 12Z. ALSO...
SREF PROBABILITIES ARE HIGH FOR STRATUS DEVELOPMENT BEHIND THE
FRONT. CONFIDENCE IS RATHER LOW ON HOW THESE FACTORS WILL BALANCE...
SO MADE LITTLE CHANGE TO MIN TEMPS. OVERALL... FORECAST LOWS ARE
VERY CLOSE TO MAV AND MET GUIDANCE.
SATURDAY... MAX TEMPS WILL BE ON THE COOL SIDE AS BLUSTERY NORTH
WINDS AND SLOWLY DECREASING CLOUD COVER ACCOMPANY SUBZERO H85 TEMPS.
FORECAST HIGHS ARE GENERALLY 2-3F BELOW MOS GUIDANCE WITH UPPER 30S
NORTH AND LOWER 40S SOUTH. NEARLY SATURATED ENVIRONMENT AND WEAK
LIFT WILL CONTRIBUTE TO LIGHT PRECIP CHANCES ACROSS NORTH CENTRAL
NEBRASKA THROUGH THE DAY. KONL TEMP PROFILE MAINLY SUPPORTS SNOW IN
THE AFTERNOON... BUT WITH HIGHS IN THE UPPER 30S AND SFC WET BULB
ABOVE 0C... TRANSITIONED BACK TO RASN MIX.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 316 PM CDT FRI MAR 25 2016
SATURDAY NIGHT THROUGH MONDAY...A BUILDING THERMAL RIDGE TAKES HOLD
ON THE FCST AREA FROM THE WEST. THE LATEST BLEND OF 4 GUIDANCE DATA
SETS PLUS BIAS CORRECTION PRODUCES HIGHS IN THE UPPER 50S TO LOWER
60S SUNDAY. THE EKD...ECE...MEX GUIDANCE BLEND PLUS BIAS CORRECTION
FOR MONDAY PRODUCES HIGHS IN THE MID TO UPPER 60S.
FULL SUN IS EXPECTED SUNDAY WITH PARTLY CLOUDY SKIES MONDAY AS SOME
MID AND HIGH CLOUDS DRIFT IN FROM A DEVELOPING UPPER LOW OVER THE
WRN U.S.. WEST WINDS SUNDAY SUPPORT DEEPER MIXING THAN THE SOUTH
WINDS AND INCREASING MOISTURE MONDAY. SO DESPITE THE WARMER AIR
ALOFT HIGHS MONDAY ARE FAIRLY MODEST. THE FORECAST IS DRY.
THE FORECAST AREA REMAINS IN THE GRIP OF ARCTIC AIR SATURDAY NIGHT
WHICH PRODUCES LOWS IN THE TEENS TO LOWER 20S. THE THERMAL RIDGE
BUILDS TO NEAR 10C AT 850MB SUNDAY NIGHT WHICH SUPPORTS LOWS IN THE
UPPER 20S TO LOWER 30S.
MONDAY NIGHT THROUGH FRIDAY...A HOT PROD REACHES INTO THE FCST AREA
TUESDAY AND H850MB TEMPERATURES SPIKE REACHING 16C TO 20C. THE GFS
IS FARTHER NORTH THAN THE ECM WHICH BACKS A COLD FRONT INTO NRN NEB.
A BLENDED APPROACH PRODUCES HIGHS IN THE 70S SOUTH AND 60S TO NEAR
70 NORTH.
AN UPPER LOW WILL DRIFT THROUGH THE ROCKIES TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT. A PIECE OF THE LOW LIFTS THROUGH THE CENTRAL HIGH
AND NRN PLAINS. THE MODELS SUGGEST THE MIDLEVEL FRONTOGENESIS WILL
BE FAR ENOUGH SOUTH TO PRODUCE RAIN OR SNOW ACROSS NWRN NEB.
THERE IS ALSO THE POTENTIAL FOR THUNDERSTORMS EAST OF HIGHWAY 83
TUESDAY NIGHT AND WEDNESDAY AS A DRYLINE SHARPENS UP AS A RESULT OF
THE HOT PROD TUESDAY. THE ECM AND GFS SHOW SOME SORT OF CONVECTION
FORMING AS A RESULT. MOST OF THIS IS EAST OF THE FCST AREA. THE
SHEAR IS STRONG WITH H500MB WINDS INCREASING TO 50 TO 70KT.
A FRESH BATCH OF ARCTIC AIR WILL SPILL INTO THE FCST AREA TUESDAY
NIGHT AND WEDNESDAY. UPPER LEVEL SUPPORT CONTINUES DURING THIS TIME
AND RAIN OR SNOW SHOWERS ARE POSSIBLE ASSOCIATED WITH COLD AIR
ALOFT...500MB TEMPERATURES AROUND -25C TO -30C.
THE MODELS ARE IN EXCELLENT AGREEMENT THURSDAY AND FRIDAY. THE DEEP
LOW PRESSURE CIRCULATING THROUGH THE PLAINS WEDNESDAY LIFTS INTO
ONTARIO FORMING A DEEP UPPER LEVEL LOW WHICH CONTINUES TO PULL LATE
SEASON ARCTIC AIR INTO THE FCST AREA. HIGHS THESE DAYS MOSTLY IN THE
40S TO LOWER 50S ARE BELOW NORMAL AS IS THE 6 TO 14 DAY OUTLOOK FROM
CPC.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 607 PM CDT FRI MAR 25 2016
MID LEVEL CLOUDS WILL MAINTAIN BKN SKIES ACROSS MOST OF WESTERN
AND NORTH CENTRAL NEBRASKA THROUGH THIS EVENING...EXCEPT FOR NORTHWEST
NEBRASKA NEAR KCDR AND KIEN WHERE LIGHT RAIN/SNOW MAY RESULT IN
MVFR CONDITIONS. BETTER MOISTURE WILL OVERSPREAD THE AREA
TONIGHT...WHICH WILL LIKELY RESULT IN MVFR CIGS. SOME SNOW
SHOWERS ARE POSSIBLE ACROSS NORTHERN NEBRASKA...MAINLY AFFECTING
KVTN...KANW...AND KONL. NORTHWEST WIND WILL ALSO STRENGTHEN
OVERNIGHT AND CONTINUE SATURDAY...WITH GUSTS EXCEEDING 20 KTS.
&&
.FIRE WEATHER...
ISSUED AT 316 PM CDT FRI MAR 25 2016
TUESDAY COULD BE AN OPPORTUNITY FOR FIRE. THE GFS AND ECM BRING A
WARM SPOKE OF DRY AIR NORTH INTO AREAS ALONG AND WEST OF HIGHWAY
83 WHICH COULD RESULT IN HUMIDITY NEAR OR BELOW 15 PERCENT. WINDS
BECOME SOUTH SOUTHWEST IN THE WARM DRY AIR AND INCREASE TO AROUND
20 MPH IMPLYING GUSTS TO 30 MPH. THE ECM IS SLOWER THAN THE GFS
AND DELAYS THE DRY AIR UNTIL TUESDAY EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SNIVELY
LONG TERM...CDC
AVIATION...ROBERG
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1237 AM CDT THU MAR 24 2016
.UPDATE...
ISSUED AT 1237 AM CDT THU MAR 24 2016
THE UPR LOW IS CURRENTLY BETWEEN HJH-BIE. THE DEFORMATION SNOW
BAND IS NOW MOVING THRU THE HEART OF THE FCST AREA. THE HIGHEST Z
IS PRODUCING MDT SN IN 1/2 MI VSBYS.
THE 18Z/00Z 4KM NAM NEST AND THE 03Z/04Z HRRR SIM Z DEPICT THIS
BAND WELL. IT WILL CONT TO DRIFT E THRU THE OVERNIGHT HRS WITH THE
BACK EDGE REACHING HWY 281 BY 09Z. BY DAWN THE SNOW SHOULD BE
COMPLETELY OUT OF THE FCST AREA (E OF HWY 81). THE INTENSITY OF
THE BAND SHOULD DIMINISH AS IT MOVES E WITH THE UPR LOW.
THERE WILL BE 1-2" OF ACCUM WHERE THE MDT SNOW PERSISTS THE
LONGEST.
WINDS CONT TO GUST TO NEAR 40 KTS. THE HIGH WIND WRNG WAS
CANCELLED EARLY. PLEASE SEE THE LATEST LSR FOR A LIST OF PEAK WIND
GUSTS OVER THE LAST 18 HRS.
THE HIGHEST GUST WAS 53 KTS AT ORD.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY DAYTIME)
ISSUED AT 321 PM CDT WED MAR 23 2016
FOCUS IS ON THE WINTER STORM SYSTEM TRACKING ACROSS THE PLAINS
TODAY/THIS EVENING. WATER VAPOR IMAGERY PLACED THE CENTER OF THE
UPPER LOW PRESSURE SYSTEM IN WESTERN KANSAS AROUND MID DAY WITH THE
ASSOCIATED SURFACE LOW NEAR KHYS. SURFACE COLD FRONTAL BOUNDARY IS
FAIRLY STATIONARY ATTM FROM JUST SOUTH OF KJYR TO KHLC. POST FRONTAL
TEMPS HAVE BEEN FAIRLY STEADY OR FALLING TODAY WHILE AHEAD OF THE
FRONT IN GOOD INSOLATION TEMPS HAVE REACHED THE 70S. MONITORING THE
WARM SECTOR AREA FOR CONVECTIVE POTENTIAL THIS AFTN AND EVENING AND
IF STORMS DEVELOP CANNOT RULE OUT THE POTENTIAL FOR SMALL HAIL.
INSTABILITY IS ALSO PRESENT FARTHER WEST BEHIND THE FRONT AND
LIGHTNING HAS BEEN COMMON ACROSS PORTIONS OF WESTERN NEBRASKA WITH
SNOW/SLEET/GRAUPEL FALLING AND COULD SEE THIS MOVING INTO OUR
WESTERN COUNTIES THIS EVENING.
AS WE HEAD INTO THIS EVENING AND TONIGHT TAKE NOTE THAT THE
PROGRESSION OF THE WINTER STORM SYSTEM HAS SLOWED...WITH THE BRUNT
OF THE PRECIPITATION MOVING IN AND FALLING DURING THE EVENING/FIRST
PART OF THE NIGHT BEFORE ENDING BY DAYBREAK THURS. AT THE ONSET PCPN
TYPE WILL BE LIQUID AS DRIZZLE/RAIN BEFORE TRANSITIONING TO SNOW AS
COLDER AIR ADVECTS SOUTH. OUR WESTERN CWA SHOULD SEE A TRANSITION TO
SNOW TOWARD 00Z WITH THE SNOW LINE GRADUALLY SHIFTING SOUTHEAST THIS
EVENING/OVERNIGHT. SNOW ACCUMULATIONS ARE TRICKY AS TEMPS ARE
EXPECTED TO BE IN THE 30S WHILE PCPN IS FALLING AND GROUND TEMPS ARE
WARM...AND ULTIMATELY THE GREATER ACCUMULATIONS WILL BE IN SNOW
BANDS. MODELS ARE FAIRLY CONSISTENT THAT THE MAIN SNOW BAND WILL SET
UP ACROSS OUR NW CWA INITIALLY AND SHIFT EAST OVERNIGHT WITH THE
NORTHERN PORTION OF CWA EXPECTED TO SEE THE POTENTIAL FOR THE
GREATER SNOW AMOUNTS. GENERALLY EXPECT AMOUNTS TO RANGE FROM 1 TO 4
INCHES BUT CANNOT RULE OUT LOCALLY HIGHER AMOUNTS IF THE SNOW BAND
IS MORE STATIONARY/NOT PROGRESSIVE. ADJUSTMENTS TO HEADLINES WERE
MADE EARLIER TO DELAY THE TIMING OF THE ONSET OF THE WINTRY WEATHER
AND HARD TO ADJUST HEADLINES ANY FURTHER ATTM AS PCPN HAS YET TO
MOVE IN AND WILL NEED TO MONITOR HOW SYSTEM EVOLVES THRU THE EVENING.
WINDS ARE THE NEXT CONCERN INTO THE NIGHT. WINDS HAVE BEEN STRONG
ALL DAY WITH GUSTS OF 40 TO 50 MPH...AND A RECENT GUST OF 56 MPH AT
KRSL THIS AFTN. WINDS ARE EXPECTED TO REMAIN STRONG THRU THE EVENING
IN A STILL TIGHT PRESSURE AS THE SFC LOW TRACKS EAST INTO NORTHERN
MO. PRESSURE RISES ARE IMPRESSIVE THIS EVENING ACROSS NORTHERN KS
AND WIND GUSTS NEAR OR ABOVE 50 MPH REMAIN POSSIBLE AND THE HIGH
WIND WARNING IS IN EFFECT FOR THE STRONG WINDS.
PRECIPITATION ENDS W/E TONIGHT AS THE SYSTEM PULLS OUT. WIND SPEEDS
WILL REMAIN STEADY/GUSTY THROUGH THE NIGHT BUT WILL GRADUALLY
DECREASE HEADING INTO THURSDAY AS THE GRADIENT RELAXES. OVERNIGHT
TEMPS WILL BE COLD...FALLING BELOW FREEZING. SUNSHINE IS EXPECTED
THURSDAY BUT KEPT TEMPS ON THE COLD SIDE ESPECIALLY FOR OUR NORTHERN
ZONES WHERE SNOW COVER IS EXPECTED.
.MID TERM...(THURSDAY EVENING THROUGH SATURDAY DAYTIME)
ISSUED AT 321 PM CDT WED MAR 23 2016
SUMMARIZING THIS 48-HOUR "MID TERM" PERIOD: ALTHOUGH NOT NEARLY
AS ACTIVE AS THE SHORT TERM WEATHER DESCRIBED ABOVE...THESE
PERIODS ARE NOT EXACTLY QUIET EITHER...AS THERE ARE SOME LOW-
CONFIDENCE/"PESKY" PRECIPITATION CHANCES TO CONTEND
WITH...POSSIBLY AS EARLY AS FRIDAY DAYTIME...BUT MORE SO FRIDAY
NIGHT INTO SATURDAY AND GENERALLY FAVORING THE SOUTHERN CWA MORE
THAN THE NORTHERN COUNTIES. FORTUNATELY...BARRING SOME FAIRLY
SIGNIFICANT CHANGES...THERE DOES NOT APPEAR TO BE ANY "HIGH
IMPACT" WEATHER DURING THIS TIME FRAME...WITH MOST OF THESE STILL-
LOW PRECIPITATION CHANCES FAVORING RAIN MORE THAN SNOW VERSUS
SNOW. THAT BEING SAID...IF HIGH TEMPERATURES FOR SATURDAY CONTINUE
TO TREND DOWN MUCH MORE... ESPECIALLY ABOUT THE NORTHWEST HALF OF
THE CWA COULD POSSIBLY SEE SOME SOME MINIMAL SNOW ACCUMULATION...
SO THIS WILL NEED WATCHED. WHAT WE DO KNOW IS THAT SATURDAY IS
TRENDING RATHER BREEZY/WINDY OUT OF THE NORTH...ALBEIT NORTHING AS
STRONG AS WHAT WE ARE EXPERIENCING WITH THIS CURRENT SYSTEM.
FIRE WEATHER CONCERNS FRIDAY?: TECHNICALLY SPEAKING...A FEW OF OUR
EXTREME SOUTHEASTERN COUNTIES (OSBORNE/MITCHELL) ARE NOW FORECASTED
TO HIT "NEAR-CRITICAL" THRESHOLDS OF RELATIVE HUMIDITY (RH)/WIND
GUSTS ON FRIDAY AFTERNOON...AS RH VALUES DROP TO AROUND 25 PERCENT
AND SOUTHERLY WIND GUST TO 20+ MPH. HOWEVER...AT LEAST FOR NOW...WE
APPEAR "SAFE" FROM CRITICAL THRESHOLDS THAT MIGHT REQUIRE HEADLINE
ISSUANCE. CONSIDERED ADDING THIS VERY LIMITED "NEAR-CRITICAL" AREA
TO THE LATEST HAZARDOUS WEATHER OUTLOOK PRODUCT (HWOGID)...BUT GIVEN
THIS IS STILL 2 DAYS AWAY...IT`S MARGINAL...AND COULD BE MITIGATED
SOMEWHAT BY ANY MEANINGFUL PRECIPITATION THAT FALLS DURING THESE
NEXT 24 HOURS...OPTED TO LEAVE IT OUT FOR NOW AND DEFER TO LATER
SHIFTS TO EVALUATE. AS FOR SATURDAY...ALTHOUGH THERE IS PLENTY OF
WIND...COOLER TEMPS WILL KEEP RH VALUES WELL-ABOVE EVEN "NEAR-
CRITICAL" THRESHOLDS.
WILL NOW TAKE A LOOK AT EACH OF THESE 4 FORECAST PERIODS IN MORE
DETAIL:
THURSDAY EVENING/NIGHT: MAINTAINED A DRY FORECAST HERE...ALTHOUGH DO
EXPECT SKIES TO GENERALLY TREND FROM MOSTLY CLEAR TO PARTLY/MOSTLY
CLOUDY AS THE NIGHT WEARS ON. IN THE MID-UPPER LEVELS...A VERY
FLEETING/BRIEF PERIOD OF SHORTWAVE RIDGING IS EVIDENT JUST AHEAD OF
THE NEXT...FAIRLY LOW-AMPLITUDE SHORTWAVE TROUGH APPROACHING THE
CENTRAL PLAINS FROM THE NORTHERN ROCKIES. AT THE SURFACE...BREEZES
START OUT THE EVENING LIGHT AND SOMEWHAT VARIABLE AS A BRIEF PERIOD
OF RIDGING PASSES BY...BUT LATER IN THE NIGHT A STEADIER 5-15 MPH
SOUTHERLY BREEZE WILL BECOME ESTABLISHED. AS A RESULT OF THE
EXPECTED CHANGES IN SKY COVER/WIND SPEEDS DURING THE NIGHT...LOW
TEMPS MAY VERY WELL OCCUR CLOSER TO MIDNIGHT THAN SUNRISE...WITH
SOME SLIGHT RISES POSSIBLE LATE IN THE NIGHT. CHANGED THESE LOWS
VERY LITTLE...STILL AIMING MOST AREAS INTO THE 28-32 RANGE.
FRIDAY DAYTIME: CONTEMPLATED "RUINING" THE GOING DRY FORECAST BY AT
LEAST ADDING A GENERIC "SLIGHT CHANCE OF SPRINKLES" TO AT LEAST
PORTIONS OF THE CWA...BUT WITH THE LOWEST LEVELS REMAINING FAIRLY
MOISTURE-STARVED...FEEL THAT MOST OF THE POSSIBLE PRECIP ON FRIDAY
WILL STRUGGLE TO REACH THE GROUND. AS A RESULT...KEPT SKY COVER IN
PARTLY-MOSTLY CLOUDY TERRITORY...BUT KEPT IT DRY FOR NOW...ALTHOUGH
NEXT FEW SHIFTS MAY AT LEAST HAVE TO CONSIDER SPRINKLES IF NOT A
SMALL CHANCE OF MEASURABLE RAIN SHOWERS. IN THE MID-UPPER
LEVELS...THE AFOREMENTIONED SHORTWAVE DISTURBANCE AFFECTS MAINLY
SD/NORTHERN NEB DURING THE DAY...BUT THERE COULD BE JUST ENOUGH LIFT
FOR SOME SPOTTY PRECIP LOCALLY. AT THE SURFACE...A FAIRLY WEAK
FRONT/TROUGH WILL PASS INTO THE CWA OVER THE COURSE OF THE
DAY...TURNING WINDS FROM SOUTHERLY TO MORE WESTERLY AND EVEN
NORTHWESTERLY WITH TIME. ROUGHLY THE SOUTHEASTERN ONE-THIRD OF THE
CWA IS MOST LIKELY TO SEE SOUTH-SOUTHWEST WIND GUSTS AS HIGH AS
AROUND 25 MPH...WITH SPEEDS AT LEAST SLIGHTLY LESS FARTHER TO THE
NORTHWEST. GIVEN THE EXPECTATION OF DECENT CLOUD COVER
OVERALL...NUDGED DOWN HIGH TEMPS 1-2 DEGREES...AIMING FOR A RANGE
FROM MID-50S FAR NORTH TO MID-60S FAR SOUTH.
FRIDAY NIGHT: ALTHOUGH MOST OF THE CWA WILL PROBABLY CONTINUE
STRUGGLING TO SEE MUCH PRECIPITATION...MAINTAINED LOW-CONFIDENCE 20-
30 PERCENT RAIN CHANCES FOR ROUGHLY THE SOUTHERN HALF OF THE
CWA...WHILE ACKNOWLEDGING A SLIGHT CHANCE OF SPRINKLES OR EVEN A FEW
LATE-NIGHT FLURRIES IN NORTHERN ZONES. IN THE MID-UPPER
LEVELS...SOME ADDITIONAL ENERGY MOVES IN FROM THE WEST-SOUTHWEST OUT
AHEAD OF A PRIMARY SHORTWAVE TROUGH MOVING SOUTHEAST INTO THE
CENTRAL ROCKIES. WHILE MOST MODELS DOWNPLAY RAIN POTENTIAL DURING
THE NIGHT...THE 12Z NAM IS A BIT MORE AGGRESSIVE WITH RAIN SHOWER
(POSSIBLY WEAK THUNDERSTORM?) ACTIVITY IN SOUTHERN ZONES THROUGH THE
NIGHT...AND HENCE THE SLIGHTLY HIGHER PRECIP CHANCES HERE. AT THE
SURFACE...THE NET EFFECT OF THE UPPER DISTURBANCES TO BOTH THE NORTH
AND WEST WILL BE TO DRIVE A FAIRLY STRONG COLD FRONT SOUTHWARD
THROUGH THE CWA...WITH NORTH WINDS PICKING UP TO AROUND 20+ MPH IN
MOST AREAS BETWEEN MIDNIGHT-SUNRISE. DESPITE COLD AIR
ADVECTION...THESE WINDS SHOULD KEEP TEMPS FROM DROPPING TOO
FAR...AND ACTUALLY NUDGED UP LOWS VERY SLIGHTLY INTO GENERALLY THE
30-36 RANGE MOST PLACES.
SATURDAY DAYTIME: AS EARLIER MENTIONED...THIS CONTINUES TRENDING
TOWARD BEING A NOT-SO-PLEASANT DAY...WITH DECENT NORTH WINDS
SUSTAINED UP AROUND 20-25 MPH WITH HIGHER GUSTS. BECAUSE MID-UPPER
FORCING LARGELY "SPLITS AROUND" THE CWA...PRECIPITATION CHANCES
REMAIN FAIRLY LOW...RANGING FROM NON-MENTIONABLE (BELOW 15 PERCENT)
IN THE FAR NORTHERN CWA...TO AROUND 30 PERCENT IN SOUTHERN ZONES. IN
FACT...MODELS SUCH AS THE ECMWF/GFS ARE ESSENTIALLY DRY CWA-WIDE.
HOWEVER...THE NAM IS MORE INSISTENT ON A BAND OF RAIN/POSSIBLY WET
SNOW AFFECTING SOUTHERN ZONES DURING THE AFTERNOON...SO HENCE THE
CONTINUED LOW PRECIP CHANCES. NUDGED DOWN HIGHS ABOUT 2
DEGREES...NOW RANGING FROM NEAR-40 FAR NORTH TO MID-UPPER 40S SOUTH.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 320 PM CDT WED MAR 23 2016
THIS SECTION FOCUSES ONLY ON THE "LONG TERM" PERIOD (DAYS 4-7) FOR
WHICH THE FORECAST IS PRIMARILY DERIVED FROM A DEFAULT MULTI-MODEL
BLEND WITH ONLY LIMITED MODIFICATION BY THE FORECASTER:
SUMMARIZING THIS 4-DAY PERIOD: GENERALLY SPEAKING...THINGS START OUT
WITH FAIRLY HIGH CONFIDENCE IN DRY AND SEASONABLE CONDITIONS (EXCEPT
FOR MAYBE SOME RAIN AND/OR SNOW RIGHT AWAY SATURDAY NIGHT IN
SOUTHERN ZONES)...BEFORE LOW-END RAIN CHANCES RE-ENTER THE OFFICIAL
FORECAST BY THE TUES NIGHT-WED TIME FRAME ALONG WITH THE POSSIBILITY
OF AT LEAST LIMITED THUNDERSTORM ACTIVITY (ESPECIALLY BY WEDNESDAY).
AT LEAST FOR NOW...THE ENTIRE SUNDAY DAYTIME-TUESDAY DAYTIME
FORECAST REMAINS VOID OF MENTIONABLE RAIN CHANCES...BUT PLEASE NOTE
THAT THERE ARE HINTS IN THE LATEST ECMWF/GFS THAT FUTURE FORECASTS
MAY BE INTRODUCING SLIGHT RAIN CHANCES AS EARLY AS THE LATE MONDAY
NIGHT-TUESDAY TIME FRAME...SOMETHING TO WATCH FOR. TEMPERATURE-
WISE...HIGHS/LOWS WERE CHANGED VERY LITTLE FROM PREVIOUS
FORECAST...WITH SEASONABLE HIGHS IN THE 50S SUNDAY THEN RISING INTO
THE 60S FOR MOST AREAS MON-WED. AS FOR OVERNIGHT LOWS...SATURDAY
NIGHT IS THE COLDEST OF THESE NIGHTS WITH LOWS WELL DOWN INTO THE
20S...WITH MILDER 30S AND EVEN SOME 40S BY MON NIGHT AND ESPECIALLY
TUES NIGHT.
POSSIBLE ELEMENTS WORTHY OF INCLUSION IN THE HAZARDOUS WEATHER
OUTLOOK (HWOGID): OFFICIALLY...NOTHING YET. FOR ONE...THE
THUNDERSTORM CHANCES JUST INTRODUCED FOR WEDNESDAY WOULD NOT GO INTO
THE HWO UNTIL TONIGHT`S SHIFT. AS FOR POSSIBLE FIRE WEATHER
DAYS...CURRENTLY THERE ARE NONE WITH AN OVERLAP OF RELATIVE HUMIDITY
BELOW 25 PERCENT AND WIND GUSTS ABOVE 20 MPH...BUT THIS WILL BEAR
WATCHING AS THESE CONDITIONS OFTEN DON`T SHOW UP IN MODELS 4+ DAYS
OUT UNLESS THEY ARE PARTICULARLY "BAD".
WILL NOW MENTION A FEW DETAILS ABOUT SPECIFIC PERIODS:
SATURDAY NIGHT: WITH A SHORTWAVE TROUGH PASSING THROUGH THE CENTRAL
PLAINS (BUT MAINLY TO OUR SOUTH)...KEPT SOME 20-30 PERCENT CHANCES
FOR RAIN/SNOW (MORE LIKELY) GOING FOR MAINLY THE SOUTHEAST 1/3 OF
THE CWA. THE ECMWF IS MORE BULLISH THAN THE GFS HERE...AND EVEN
SUGGESTS SOME LIGHT SNOW ACCUMULATION IS POSSIBLE MAINLY IN OUR KS
ZONES.
SUNDAY DAYTIME-NIGHT: CONFIDENCE IS PRETTY DARN HIGH IN A DRY 24
HOURS HERE AS SHORTWAVE RIDGING MOVES IN ALOFT BEHIND THE DEPARTING
WAVE...ALTHOUGH RIGHT AWAY SUNDAY MORNING THE VERY BACK EDGES OF
SNOW COULD STILL BE FLIRTING WITH OUR EXTREME SOUTHEAST CWA BEFORE
DEPARTING WELL TO THE EAST. LIGHTER WINDS THAN SATURDAY AND TEMPS
RISE ANYWHERE FROM 7-15 DEGREES VERSUS SATURDAY...WITH ALL AREAS
INTO THE 50S.
MONDAY DAYTIME-NIGHT: KEPT IT DRY HERE...AND LIKELY WILL BE FOR AT
LEAST THE DAYTIME HOURS...BUT FUTURE FORECASTS MAY NEED TO CONSIDER
SOME SHOWER CHANCES FOR LATE IN THE NIGHT AS THE VERY LEADING EDGES
OF ELEVATED MOISTURE RETURN/LIFT REACHES THE AREA WELL OUT AHEAD OF
A LARGE-SCALE TROUGH OVER THE WESTERN CONUS.
TUESDAY DAYTIME-WEDNESDAY DAYTIME: AT LEAST FOR NOW...TUES DAYTIME
FORECAST REMAINS DRY...BUT THE ENTIRE CWA HAS AT LEAST 20-30 PERCENT
RAIN CHANCES FOR TUES NIGHT-WED AS THE CENTRAL PLAINS BECOMES
INCREASINGLY-INFLUENCED BY THE WESTERN CONUS TROUGH. AS IS USUALLY
THE CASE...MODELS VARY CONSIDERABLY IN THE DETAILS...WITH THE GFS
FAVORING TUES NIGHT PRECIP A BIT MORE AND THE ECMWF MORE-SO FAVORING
WED DAYTIME. OF COURSE...IT`S FUTILE/POINTLESS AT THIS DAY 6-7 RANGE
TO TRY WORKING OUT TIMING DETAILS...SO HENCE THE BLANKET RAIN
CHANCES THE ENTIRE TIME. AS FOR THUNDERSTORM INTENSITY...ALTHOUGH
THIS DOES NOT LOOK LIKE AN "OBVIOUS" SEVERE WEATHER THREAT...IT`S
STILL A WEEK AWAY AND WITH APRIL FAST APPROACHING...IT SURE WON`T
TAKE MUCH TO GET AT LEAST STRONG/MARGINALLY SEVERE STORMS.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THU NIGHT)
ISSUED AT 1237 AM CDT THU MAR 24 2016
SIGNIFICANT WEATHER: IFR SNOW CONTS THRU 09Z THEN ENDS. STRONG N
WINDS.
REST OF TONIGHT: IFR SNOW WITH VSBYS TEMPO DOWN TO 1/2SM...ENDING
09Z-10Z. BECOMING VFR 10Z-12Z. N WINDS WILL CONT TO G40 KTS BUT
GRADUALLY SUBSIDE. CONFIDENCE: HIGH
THU: VFR WITH A FEW PATCHES OF 25K FT CIRROSTRATUS. NNW WINDS CONT
TO DIMINISH BUT WILL STILL GUST UP TO 26 KTS BEFORE 17Z.
CONFIDENCE: HIGH
THU EVE: VFR WITH THICKER 25K FT CIRROSTRATUS MOVING IN FROM THE
W. WINDS DROP BELOW 10 KTS AND SHIFT TO SW. CONFIDENCE: HIGH
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER STORM WARNING UNTIL 7 AM CDT THIS MORNING FOR NEZ041-047-
048-061-062-072>075-082>084.
WINTER STORM WARNING UNTIL 4 AM CDT EARLY THIS MORNING FOR
NEZ039-040-046-060.
WINTER WEATHER ADVISORY UNTIL 7 AM CDT THIS MORNING FOR NEZ049-
063.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...FAY
LONG TERM...PFANNKUCH
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1137 PM CDT WED MAR 23 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 342 PM CDT WED MAR 23 2016
THE SLOWER RAP MODEL AND HRRR MODEL ARE PREFERRED WHICH CONTINUE
SNOW CONTINUING IN EASTERN AREAS FOR A FEW HOURS AFTER MIDNIGHT.
THE BETTER GUESS IS WHEN THE THIRD OF THREE SNOW BANDS DEVELOPS
LATER TONIGHT ACROSS CENTRAL NEBRASKA...THE SECOND ONGOING SNOW
BAND WILL FALL APART.
THE FORECAST BLENDS SOME OF THE SLOWER RAPID UPDATE MODELS WITH
THE PREVIOUS FORECAST WHICH ADDS AN INCH OR TWO SNOW ACCUMULATION
ACROSS SWRN NEB AND PARTS OF THE CENTRAL SANDHILLS. GIVEN THE
WARM GROUND AND SNOWFALL RATES OF AN INCH OR LESS PER HOUR THUS
FAR...FORECAST ACCUMULATIONS COULD ACTUALLY BE TOO HIGH IN THE
LOWER ELEVATIONS.
WIND GUSTS OF 50 TO 55 MPH SHOULD CONTINUE IN THE OPEN AREAS
EARLY THIS EVENING AND THEN DROP OFF. EARLIER GUSTS OF 60 TO 64
MPH HAVE VANISHED. MOST OF THOSE GUSTS WERE MOMENTUM TRANSPORT
FROM 65 KT WINDS AT 3KFT PER KLNX VWP SO THE GUSTS ARE AT THE
MERCY OF VERTICAL MIXING.
SKIES BY MORNING SHOULD BE GENERALLY CLEAR WITH DRIER AIR MOVING
IN AT ALL LEVELS. THE LOWS IN THE TEENS AND LOWER 20S ARE MODEST.
WINDS ALOFT WOULD CONTINUE STRONG PREVENTING A DEEP INVERSION IN
MOST AREAS. THE EXCEPTION IS THE WRN SANDHILLS WHERE SINGLE OR
NEAR SINGLE DIGITS AREA EXPECTED.
ALL FORECAST HIGHLIGHTS WILL OPERATE IN PLACE. NO UPGRADES APPEAR
TO BE NEEDED AT THIS TIME AS THE SYSTEM HAS GENERALLY BEEN WELL-
BEHAVED. THERE IS STILL ROOM FOR A SURPRISE GIVEN THE STRENGTH OF
THIS STORM.
LASTLY...THE OCCASIONAL LIGHTNING AND THUNDERSTORMS ARE THE
RESULT OF ELEVATED CAPE. THE RAP HAS SHOWN ONLY WEAK SKILL WITH
THIS FEATURE. THE 750MB BARRIER JET IS QUITE STRONG.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM CDT WED MAR 23 2016
A LOW PRESSURE SYSTEM WILL PUSH ACROSS THE NORTHERN PLAINS
THURSDAY NIGHT AND FRIDAY...DRAGGING A COLD FRONT ACROSS THE AREA
LATE IN THE DAY ON FRIDAY. A SLIGHT WARM UP TO AROUND 50 AHEAD OF
THE FRONT. MOISTURE IS LIMITED...HOWEVER MODELS MAY BE UNDERDONE
ON WHAT IS AVAILABLE IN THE BOUNDARY LAYER DUE TO EXPECTED SNOW
MELT/EVAPORATION FROM PRECIP FROM ONGOING STORM. THAT
SAID...MODELS FOCUS MOST OF THE ENERGY ACROSS THE NORTH...WITH
POCKETS ACROSS THE CWA. THUS WILL CONTINUE TO HAVE LOW POPS.
TEMPS COOL OFF BEHIND THE FRONT WITH RAIN POSSIBLY MIXING WITH
SNOW INTO FRIDAY NIGHT. MOST AREAS WILL BE DRY BY
SATURDAY...HOWEVER THE WESTERN SIDE OF THE FRONT STALLS NEAR THE
NEB/KS BORDER AND COLD LINGER SOME RAIN/SNOW ACROSS FAR
SOUTHWESTERN NEB INTO SATURDAY. COLD AIR IS DRAWN IN BEHIND THE
FRONT WITH HIGHS ONLY AROUND 40 FOR SATURDAY. A GOOD 10 TO 15
DEGREES BELOW NORMAL FOR THE LAST WEEK OF MARCH.
WARM FRONT TO PUSH ACROSS THE AREA WITH A WARM UP FOR EASTER
SUNDAY. HIGHS BACK CLOSER TO NORMAL...50S...AND DRY. EVEN
WARMER...60S...FOR MONDAY INTO TUESDAY. THEN THE NEXT SYSTEM
EJECTS ONTO THE PLAINS FOR MID WEEK...AND BRING ANOTHER CHANCE
FOR RAIN/SNOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1137 PM CDT WED MAR 23 2016
CONDITIONS HAVE IMPROVED TO VFR AT KLBF AS THE WESTERN EDGE OF
THE WINTER STORM HAS MOVED EAST INTO CENTRAL AND EASTERN NEBRASKA.
VFR CONDITIONS ARE FORECAST AT THE KLBF AND KVTN TERMINALS THE
NEXT 24HRS. WESTERLY WINDS THURSDAY ARE FORECAST TO BE LIGHT AOB
10KTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 AM CDT THURSDAY FOR NEZ010-027>029-
038-059-070.
WINTER WEATHER ADVISORY UNTIL 1 AM CDT THURSDAY FOR NEZ071.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS RALEIGH NC
744 PM EDT FRI MAR 25 2016
.SYNOPSIS... A SLOW MOVING COLD FRONT WILL CROSS THE AREA LATE THIS
AFTERNOON AND EVENING. COOL HIGH PRESSURE WILL WEDGE SOUTH INTO THE
AREA TONIGHT AND SATURDAY AS THE FRONT STALLS ALONG THE SOUTHEAST
COAST THROUGH THE WEEKEND. A WAVE OF LOW PRESSURE WILL DEVELOP ON
THE FRONT ALONG AND WILL TRACK THROUGH THE SOUTHEAST STATES
SUNDAY AND INTO MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 330 PM FRIDAY...
THE SYNOPTIC COLD FRONT IS STILL INCHING ITS WAY EAST OF THE
MOUNTAINS...WITH A PREFRONTAL/LEE TROUGH AND STRENGTHENING
CONVERGENCE EVIDENT IN A GROWING CU FIELD OVER THE NORTHWEST AND
NORTHERN PIEDMONT. MLCAPE IS HIGHEST OVER THE NORTHERN COASTAL
PLAIN...PER SPC MESOANALYSIS...WHERE DEEP MOISTURE IS GREATER AND PW
IS AROUND 1.25". SHOWERS AND AN ISOLATED STORM IS STILL POSSIBLE
AS THE CONVERGENCE INCREASES INTO THE MORE UNSTABLE AIR...SO WILL
MAINTAIN CHANCE POPS NORTHEAST OF THE TRIANGLE. THE HRRR SHOWS SOME
ADDITIONAL SHOWERS DEVELOPING ALONG THE FRONT IN THE 00-03Z AND
ACTUALLY CONTINUING THROUGH 06Z AS THE INDUCED ISENTROPIC LIFT
AROUND 295K TO THE NORTH OF THE FRONT SATURATES A SHALLOW LAYER.
THIS SHOULD BE ISOLATED IN NATURE AND DIMINISH FROM NORTHWEST TO
SOUTHEAST THROUGH THE NIGHT. IF SKIES CLEAR ALOFT..WHICH VISIBLE
IMAGERY SUGGESTS IS POSSIBLE...THEN SOME FOG MAY BRIEFLY DEVELOP
AHEAD OF THE FRONT BEFORE NORTHEAST WINDS TAKE OVER. LOWS 47-55.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 330 PM FRIDAY...
THE COLD FRONT CROSSING THE AREA TONIGHT IS STILL FORECAST TO STALL
OVER SC ON SATURDAY...WITH A WAVE OF LOW PRESSURE TO TRACK ALONG THE
FRONT TOWARD THE NC COAST IN RESPONSE TO A LOW-AMPLITUDE SHORTWAVE
EJECTING OUT OF THE CENTRAL US TROUGH. DEEPENING..BUT STILL RATHER
SHALLOW ISENTROPIC UPGLIDE WILL LEAD TO INCREASE COVERAGE OF LIGHT
RAIN FROM SOUTH TO NORTH DURING THE DAY...A TREND NOTED IN THE PAST
2 OR 3 RUNS OF MOST GUIDANCE. QPF WILL BE LIGHT...A FEW HUNDREDTHS
OF AN INCH...AND THE RAIN SHOULD TAPER OFF TO DRIZZLE SATURDAY NIGHT
AS THE SURFACE WAVE MOVES OFF TO THE NORTHEAST. HIGHS HAVE BEEN
LOWERED SEVERAL DEGREES INTO THE UPPER 50S AND LOWER 60S. OVERNIGHT
LOWS IN THE UPPER 40S AND LOWER 50S.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 350 PM FRIDAY...
SPLIT STREAM FLOW ACROSS THE PACIFIC AND WESTERN NOAM WILL CONVERGE
OVER THE EASTERN U.S. BY SUNDAY...BUT WITH THE ASSOCIATED STRONGEST
FORCING FOR ASCENT AND RAIN CHANCES/AMOUNTS WITHIN EACH BRANCH
LIKELY TO SPLIT CENTRAL NC. NONETHELESS...ISENTROPIC UPGLIDE ATOP A
LINGERING HYBRID CAD REGIME OVER THE MIDDLE ATLANTIC STATES WILL
LIKELY MAINTAIN CLOUDY AND COOLER THAN AVERAGE CONDITIONS THROUGH
THE WEEKEND. THE RELATIVE HIGHEST RAIN CHANCES AND AMOUNTS WILL BE
FOCUSED ALONG 1) ALONG AND ON THE IMMEDIATE COOL SIDE OF THE WEDGE
FRONT OVER THE SOUTHERN/SOUTHEASTERN RAH CWA...AND 2) OVER THE NW
PIEDMONT...WHERE DEEPER LIFT AND SATURATION FROM NORTHERN STREAM
INFLUENCE LIFTS NORTHEAST AND MAXIMIZES ACROSS WESTERN NC AND VA.
PRECIPITATION AMOUNTS ARE LIKELY TO RANGE FROM AROUND A TENTH TO
QUARTER OF AN INCH IN BOTH AREAS...WITH LESSER AMOUNTS IN BETWEEN.
A COLD FRONT ACCOMPANYING THE NORTHERN STREAM WILL CROSS CENTRAL NC
ON MONDAY...WHICH WILL RESULT IN A CHANCE OF A SHOWER IN THE COASTAL
PLAIN MON AFTERNOON...WITH OTHERWISE CLEARING AND COOLING CONDITIONS
EXPECTED TO FOLLOW THROUGH MID-WEEK...INCLUDING SOME MID TO UPPER
30S POSSIBLE WITH GOOD RADIATIONAL COOLING AS THE CENTER OF THE
INCOMING SURFACE RIDGE SETTLES ACROSS THE MIDDLE ATLANTIC REGION.
THE PATTERN WILL TURN UNSETTLED AGAIN LATE IN THE WEEK...AS A
BROAD/ELONGATED POSITIVELY-TILTED UPPER TROUGH EVOLVES FROM THE CA
BAJA TO HUDSON BAY...AND CONSEQUENTLY DIRECTS CYCLONIC SOUTHWEST
FLOW ALOFT ACROSS THE GULF OF MEXICO AND UP THE EAST COAST. AN
ACCOMPANYING WAVY SURFACE FRONTAL ZONE WILL MOVE EAST OF THE
APPALACHIANS THU...AND SLOW AS IT MOVES TOWARD THE COAST BY EARLY
THIS WEEKEND...YIELDING HIGHER THAN AVERAGE RAIN CHANCES DURING THAT
TIME.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 740 PM FRIDAY...
24 HOUR TAF PERIOD: A COLD FRONT WILL SLOWLY SINK SOUTHWARD THROUGH
THE AREA THIS EVENING AND OVERNIGHT... BEFORE STALLING TO THE SOUTH
AND EAST OF CENTRAL NC. A FEW SHOWERS AND BRIEF SUB-VFR CONDITIONS
WILL BE POSSIBLE AS THE FRONT MOVES THROUGH THE AREA TONIGHT.
AREAS OF MVFR CEILINGS WILL BECOME MORE WIDESPREAD AS SOUTHERLY FLOW
RUNS ATOP THE COOLER AIRMASS MOVING IN LATE TONIGHT INTO SATURDAY.
RAIN AND DRIZZLE SHOULD INCREASE FROM SOUTH TO NORTH DURING THE DAY
(BEST CHANCE AT KFAY THROUGH 00Z SUNDAY) ON SATURDAY AS A WAVE OF
LOW PRESSURE TRACKS ALONG THE STALLED FRONT OVER SC TOWARD THE NC
COAST.
OUTLOOK: THE FRONT WILL STALL OFF THE NC COAST THROUGH EARLY NEXT
WEEK. SHALLOW OVERRUNNING NORTH OF THE STALLED FRONT WILL SUPPORT A
PROLONGED PERIOD OF SUB-VFR CEILINGS ACROSS THE AREA THROUGH THE
WEEKEND WITH PRECIP CHANCES INCREASING SUNDAY AND INTO MONDAY AS A
WAVE OF LOW PRESSURE DEVELOPS AND TRACKS NE ALONG THE FRONT. VFR
CONDITIONS ARE EXPECTED TO RETURN BY MONDAY EVENING.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...22
SHORT TERM...22
LONG TERM...26
AVIATION...7/22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 PM EDT THU MAR 24 2016
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL EXTEND ACROSS THE SOUTHEASTERN UNITED
STATES UNTIL A COLD FRONT CROSSES THE REGION ON FRIDAY. THE FRONT
WILL THEN SETTLE SOUTH ACROSS SOUTH CAROLINA AND LINGER THROUGH THE
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 315 PM THURSDAY...
BERMUDA HIGH PRESSURE CONTINUES TO DOMINATE WITH AN UNSEASONABLY
WARM AND SLOWLY MOISTENING AIRMASS OVER THE SOUTHEAST STATES. GUSTY
SOUTH-SOUTHWESTERLY WINDS WILL SUBSIDE THIS EVENING...SETTLING DOWN
TO AROUND 10-12KT AFTER SUNSET AS SLOW MOVING COLD FRONT CRAWLS
THROUGH THE TENN VALLEY AND EVENTUALLY ACROSS THE MOUNTAINS. IT
SEEMS LIKE EVERY MODEL RUN SHOWS A LATER AND LATER ARRIVAL OF THE
FRONT AS ITS PRIMARY UPPER SHORTWAVE SHEARS OFF INTO THE GREAT LAKES
AND THE FRONT RUNS INTO THE PERSISTENT SUB-TROPICAL RIDGE. WITH
ONLY WEAK HEIGHT FALLS AND A RELATIVELY WEAK UPPER JET RIGHT
ENTRANCE REGION....FORCING WILL BE LIMITED TO MAINLY LOW-LEVEL
CONVERGENCE AND THE POSSIBILITY OF AN MCV OR TWO EMANATING FROM GULF
CONVECTION.FORECAST SOUNDINGS DO SHOW SOME WEAK INSTABILITY
DEVELOPING AFTER MIDNIGHT AS THE LOW-LEVELS MOISTEN...THOUGH IT IS
MOSTLY ELEVATED AFTER NOCTURNAL COOLING. THE HRRR SHOWS A
PREFRONTAL BAND OF SHOWERS AND STORMS STRETCHING FROM KENTUCKY TO
ALABAMA THIS AFTERNOON WEAKENING AS IT MOVES INTO WESTERN
NC...LEAVING REALLY JUST A FEW SHOWERS IN THE WESTERN/SOUTHERN
PIEDMONT THROUGH 12Z. BACKED POPS OFF TO JUST HIGH END CHANCE AND
ITS ENTIRELY POSSIBLE THEY ARE STILL TOO HIGH. OVERNIGHT LOWS IN
THE UPPER 50S TO MID 60S LOOK GOOD GIVEN THE STEADY SOUTHERLY WIND
AND INCREASINGLY OVERCAST SKIES.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
AS OF 315 PM THURSDAY...
ONGOING SHOWERS ALONG THE FLOW MOVING FRONT...IF THERE ARE
ANY...SHOULD FIRE BACK UP INTO SOME DEEPER CONVECTION AS THE
COASTAL PLAIN DESTABILIZES (UP TO A 1000 J/KG EAST OF US HWY 1). WHILE
DEEP LAYER WIND FIELDS WILL BE STRONG OVERALL... 40-50KT OF 0-6 KM
BULK SHEAR...THE LOW-LEVEL JET DEPARTING TO THE NORTH AND LACK OF
UPPER FORCING SHOULD LIMIT THE ORGANIZATION OF CONVECTION. A FEW
STRONG STORMS ARE STILL POSSIBLE. WITHOUT MORE WIDESPREAD PRECIP
AND INCREASING BREAKS IN CLOUDS BY MIDDAY...HIGHS SHOULD RANGE FROM
THE LOWER 70S WEST TO UPPER 70S EAST. THE COLD FRONT WILL THEN
FINALLY SURGE ALL THE WAY SOUTH THROUGH THE AREA FRIDAY EVENING AS
HIGH PRESSURE NOSES IN FROM EASTERN CANADA. THE NORTH-NORTHEASTERLY
FLOW WILL BE SHALLOW...WITH SOUTHWESTERLY WINDS ABOVE
3000FT...LEADING TO THE POTENTIAL FROM STRATUS...ESPECIALLY OVER THE
EAST. LOWS 46-53.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 130 PM THURSDAY...
SAT AND SAT NIGHT: A LOW PRESSURE WAVE WILL MOVE NE ALONG THE COLD
FRONT STALLED TO OUR SOUTH...AND WILL SPREAD MOISTURE BACK ACROSS
ERN NC DURING THE DAYTIME. HOWEVER IT APPEARS THAT THE BULK OF
PRECIP SHOULD REMAIN CLOSER TO THE COAST. FARTHER W...THE CAD WEDGE
WILL BE IN PLACE...SO LOOK FOR PARTLY TO MOSTLY CLOUDY SKIES WITH
TEMPS A FEW DEG BELOW NORMAL.
SUN AND SUN NIGHT: LOW PRESSURE WILL MOVE FROM THE NORTHERN GULF
COAST NEWD ACROSS THE CAROLINAS. RAIN CHANCES WILL QUICKLY INCREASE
DURING THE MORNING...WITH THE HEAVIEST RAIN PROGGED ACROSS THE
EASTERN HALF OF THE STATE IN CONJUNCTION WITH THE AFOREMENTIONED
BOUNDARY TO OUR SOUTH LIFTING N AS A WARM FRONT AHEAD OF THE LOW
PRES WAVE. AS ALWAYS THE CASE WHEN LOW PRESSURE MOVES ACROSS THE
CAROLINAS...WE`LL HAVE TO KEEP A CLOSE EYE ON THE POTENTIAL FOR
CONVECTIVE ACTIVITY...BUT IN THIS CASE IT APPEARS THAT THE WARM
SECTOR SHOULD REMAIN MOSTLY EAST OF THE I-95. WITH CLOUDS AND
PRECIP...LOOK FOR LITTLE DIURNAL TEMP CHANGE...SO HIGHS NEAR 70
DURING THE DAY WILL ONLY COOL OFF ABOUT 10 DEG OR SO AT NIGHT.
MON: SHOULD BE TRANSITION DAY AS THE AFOREMENTIONED LOW AND PARENT
UPPER SHORT WAVE TROUGH MOVE ACROSS THE STATE ...FOLLOWED BY
DECREASING CLOUDS LATER IN THE DAY. NOT MUCH OF AN AIRMASS CHANGE
BEHIND THIS SYSTEM...SO LOOK FOR HIGHS ONCE AGAIN NEAR 70.
MON NIGHT THROUGH WED: FAIR WEATHER AND SEASONABLE TEMPS (LOWS
AROUND 40 AND HIGHS IN THE MID-UPR 60S) DURING THIS TIME AS HIGH
PRESSURE BUILDS INTO AND ACROSS THE CAROLINAS.
THUR: WITH THE NEXT COLD FRONT APPROACHING LATE IN THE WEEK...RAIN
CHANCES WILL INCREASE AS THE DAY PROGRESSES.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 130 PM THURSDAY...
VFR CONDITIONS WILL CONTINUE THROUGH 25/06Z...WITH CLOUDS GRADUALLY
THICKENING AND LOWERING AS A COLD FRONT...NOW APPROACHING THE TN
VALLEY...MOVES EAST TOWARD OUR AREA. WINDS THE REST OF THIS
AFTERNOON WILL REMAIN S/SW 10-20KT WITH HIGHER GUSTS IN THE
PREFRONTAL FLOW AHEAD OF THE FRONT. FLT CONDITIONS WILL LOWER TO
MVFR BETWEEN 25/06Z TO 25/10Z AS THE FRONT CLOSES IN ON OUR
AREA...WITH SCATTERED SHOWERS AND LOCALIZED IFR CONDITIONS POSSIBLE
DURING THIS TIME. AFTER 25/12Z...A FEW TSTMS MAY DEVELOP...
PARTICULARLY ACROSS THE COASTAL PLAIN EASTWARD. BY 25/18Z...THE
FRONT SHOULD BE MOVING ACROSS THE I-95 CORRIDOR...WITH THE RISK FOR
PRECIP ENDING QUICKLY IN ITS WAKE.
BEYOND 25/18Z THROUGH THE MIDDLE OF NEXT WEEK: FLT CONDITIONS WILL
BRIEFLY IMPROVE LATE FRIDAY INTO EARLY SUNDAY...BUT WITH THE
AFOREMENTIONED COLD FRONT STALLED JUST TO OUR SOUTH...AND A SERIES
OF LOW PRESSURE WAVES MOVING ALONG IT...SUB-VFR CONDITIONS MAY BE
POSSIBLE AGAIN DURING THE WEEKEND INTO MONDAY. FLT CONDITIONS WILL
THEN IMPROVE TO VFR DURING THE MID-WEEK PERIOD.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...2222
SHORT TERM...22
LONG TERM...RAH
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
101 AM CDT THU MAR 24 2016
.UPDATE...
ISSUED AT 100 AM CDT THU MAR 24 2016
INHERITED FORECAST MAINLY ON TRACK. DID LOWER TEMPERATURES SOUTH
WHERE WE ARE BELOW FORECAST MINS. A CLEAR SKY...LIGHT WINDS...AND
DRY AIR ALLOWING TEMPERATURES TO DROP THROUGH THE TEENS OVER THIS
AREA. OTHER CHANGE WAS TO MENTION SLIGHT CH OF LIGHT MIXED
PRECIPITATION NORTHWEST. ECHOS IN NORTHEASTERN MONTANA HOLDING
TOGETHER...SO WANTED TO HAVE SOME MENTION. WILL CONTINUE TO
MONITOR IN CASE POPS NEED TO BE RAISED. MODELS MAINLY DRY AND
DISSIPATE THE PRECIPITATION AS IT MOVES INTO WESTERN ND.
UPDATE ISSUED AT 929 PM CDT WED MAR 23 2016
QUIET WEATHER CONTINUES OVER THE AREA. A FEW VERY LIGHT SHOWERS
NOTED OVER CENTRAL MOVING INTO EASTERN MONTANA...THOUGH HAVE KEPT
OUR FORECAST DRY IN LINE WITH LATEST HIGH RES-GUIDANCE AS SHOWERS
MOVE INTO DRIER AIR. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 622 PM CDT WED MAR 23 2016
QUIET WEATHER CONTINUES OVER MUCH OF THE AREA. MAIN CHANGE TO THE
FORECAST FOR EARLY EVENING UPDATE WAS TO INCREASE CLOUD COVER OVER
THE FAR WEST...THOUGH THESE LOW LEVEL CLOUDS CONTINUE TO SLOWLY
ERODE. HIGHER LEVEL CLOUDS WILL START TO MOVE IN LATER THIS
EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 331 PM CDT WED MAR 23 2016
THE MAIN FORECAST CONCERN IN THE SHORT TERM PERIOD WILL BE THE
POSSIBILITY OF CLOUD COVER IN THE WEST LINGERING INTO THE EARLY
EVENING HOURS. ATTENTION THEN SHIFTS TO THURSDAY FOR SOME POSSIBLE
FIRE WEATHER CONCERNS.
CURRENTLY...COOL AND DRY HIGH PRESSURE CENTER WAS OVER SOUTHEASTERN
MANITOBA...WITH A HIGH PRESSURE RIDGE AXIS EXTENDING SOUTHWESTWARD
FROM THE LOW CENTER. THIS DRY AIR CONTINUED TO MOVE WESTWARD
ACROSS NORTH DAKOTA...ERODING THE CLOUD COVER FROM EAST TO WEST. THE
WESTERN THIRD OF THE STATE REMAINS UNDER SOME STRATUS AND MID-LEVEL
CLOUDS. MEANWHILE A VIGOROUS STORM SYSTEM OVER THE CENTRAL AND
SOUTHERN PLAINS CONTINUED TO PRODUCE GUSTY WINDS...RAIN...AND SNOW
FROM COLORADO TO THE GREAT LAKES.
THE SHORT TERM RAP AND HRRR INDICATE THE CLOUDS OVER WESTERN NORTH
DAKOTA SHOULD BECOME SCATTERED LATE THIS AFTERNOON/EARLY EVENING AS
THE DRIER AIR FROM THE HIGH PRESSURE RIDGE AXIS PUSHES WESTWARD.
TONIGHT AND THURSDAY THE CENTRAL PLAINS STORM CENTER MOVES
EAST...THEN NORTHEAST TOWARDS THE GREAT LAKES. THE NORTHWEST FLOW
ALOFT TONIGHT OVER NORTH DAKOTA IS INTERRUPTED BY A SHORTWAVE RIDGE
OVER THE STATE ON THURSDAY. THIS SHORT-LIVED DRYING OF THE LOW/MID
LAYERS WILL PROVIDE A CHANCE FOR A MIX-OUT SURFACE-TO-H800. THIS IS
SUPPORTED BY FORECAST BUFKIT SOUNDINGS AS WELL. THUS USED A BLEND OF
SHORT TERM AND BCCONSMOS FOR MINIMUM RELATIVE HUMIDITY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT WED MAR 23 2016
AN UPPER LEVEL SHORTWAVE OVER THE PACIFIC NORTHWEST TONIGHT MOVES
INTO THE ROCKIES THURSDAY AND INTO THE FRONT RANGE AND WESTERN
DAKOTAS THURSDAY NIGHT. SURFACE LOW PRESSURE DEVELOPS IN RESPONSE
OVER EASTERN MONTANA...WITH COLDER AIR TO THE NORTH IN SOUTHERN
CANADA...AND WARMER AIR TO THE SOUTHWEST OVER WYOMING. A COLD
FRONTAL BOUNDARY DEVELOPS ALONG THE CANADIAN BORDER...WHILE A WARM
FRONT EXTENDING SOUTH FROM THE LOW DEVELOPS THURSDAY NIGHT.
SCATTERED TO ISOLATED AREAS OF RAIN AND SNOW EXPECTED THURSDAY
NIGHT. TEMPERATURE PROFILES SUPPORT WARM AIR ALOFT COINCIDENT WITH
COLDER AIR AT THE SURFACE TO RESULT IN CHANCES OF LIGHT FREEZING
RAIN...MAINLY NORTH CENTRAL COUNTIES THURSDAY NIGHT...AND FOR A
BRIEF HOUR OR TWO POSSIBLE FARTHER SOUTH TOWARDS LAKE SAKAKAWEA AND
INTERSTATE 94 BEFORE/AROUND SUNRISE FRIDAY MORNING.
BY SUNRISE FRIDAY EXPECT SOME LIGHT SNOW ACCUMULATIONS POSSIBLE
ALONG THE CANADIAN BORDER.
FRIDAY AND FRIDAY NIGHT THE UPPER LEVEL SHORTWAVE MOVES SOUTHEAST
ACROSS THE DAKOTAS. THE SURFACE LOW IS FORECAST TO MOVE INTO EASTERN
NORTH DAKOTA BY NOON ON FRIDAY...WITH COLD ADVECTION ALREADY TAKING
PLACE OVER NORTHERN AND INTO SOUTHWESTERN NORTH DAKOTA. INCREASING
CHANCES OF RAIN FRIDAY WITH HIGH CHANCES OF LIGHT SNOW NORTH AND
LIGHT RAIN SOUTH. EXPECT AROUND AN INCH OF SNOW ACCUMULATION DURING
THE DAYTIME FRIDAY. BY FRIDAY NIGHT THE BETTER CHANCES OF
PRECIPITATION ARE ACROSS SOUTHERN NORTH DAKOTA. RAIN CHANGING TO
SNOW WITH A FEW TENTHS OF AN INCH TO 1 INCH OF SNOW POSSIBLE ACROSS
SOUTHERN COUNTIES.
IN SUMMARY...CHANCES OF RAIN AND SNOW THURSDAY NIGHT THROUGH FRIDAY
NIGHT...WITH SOME AREAS OF FREEZING RAIN NORTH CENTRAL LATE THURSDAY
NIGHT INTO EARLY FRIDAY MORNING. SNOW AMOUNTS OF UP TO AN INCH
POSSIBLE...MAINLY ACROSS THE NORTH AND SOUTH CENTRAL...BY DAYBREAK
SATURDAY.
MAINLY DRY FOR THE WEEKEND INTO EARLY NEXT WEEK WITH A SLOW WARMING
TREND.
THE MEDIUM RANGE MODELS ARE STILL IN DISAGREEMENT REGARDING A STORM
SYSTEM FOR NEXT WEEK...BUT THE LATEST 12Z RUNS ARE SHOWING A
POSSIBLE TREND TOWARD BETTER AGREEMENT. THE STORM SYSTEM IS
FORECAST TO DEVELOP FROM A LONGWAVE TROUGH OVER
THE WEST COAST SUNDAY...DEEPENING OVER THE ROCKIES
MONDAY/TUESDAY...AND EXPANDING INTO THE PLAINS TUESDAY
NIGHT/WEDNESDAY WITH THE LONGWAVE TROUGH REMAINING OVER THE CONUS
THROUGH MUCH OF NEXT WEEK. THE GFS HAS BEEN BULLISH ON DEVELOPING
A LARGE STORM SYSTEM REACHING WELL INTO THE NORTHERN PLAINS THAT
WOULD BRING WIDESPREAD RAIN AND SNOW TO NORTH DAKOTA. THE ECMWF IS
NOW DEPICTING A STRONGER SHORTWAVE EJECTING OUT OF THE BASE OF THE
LOW THAT IN TURN DEVELOPS A SURFACE LOW IN A REASONABLY SIMILAR
PLACE IN THE MISSOURI AND UPPER MISSISSIPPI VALLEY. CHANCES OF RAIN
OR SNOW REMAIN IN THE FORECAST FOR TUESDAY/WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 100 AM CDT THU MAR 24 2016
VFR CONDITIONS EXPECTED FOR THE MAJORITY OF THE PERIOD. MAY SEE A
BRIEF PERIOD OF LIGHT FREEZING RAIN OR SLEET AT KISN EARLY THIS
MORNING. NOT ENOUGH CONFIDENCE TO INCLUDE IN THE TERMINAL FORECAST
AT THIS TIME...AND WILL CONTINUE TO MONITOR. DETERIORATING
CONDITIONS THURSDAY NIGHT AND FRIDAY AS A CLIPPER STORM SYSTEM
MOVES INTO THE REGION.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...JV
LONG TERM...JV
AVIATION...NH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
314 PM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT CROSSES TONIGHT. LINGERING LOW LEVEL MOISTURE FRIDAY. HIGH
PRESSURE SYSTEM ARRIVES FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
MAIN FOCUS FOR NEAR TERM FORECAST IS COLD FRONT APPROACHING FROM
THE WEST. CLOUDS MAKING IT INTO THE OHIO RIVER VALLEY NOW AS THE
COLD FRONT ENTERS WESTERN KY/IN. HAVE A PRE-FRONTAL BAND OF
PRECIPITATION STRETCHING FROM WESTERN OHIO THROUGH CENTRAL KY.
THIS BAND WILL MOVE THROUGH LATE THIS AFTERNOON AND THIS EVENING.
ONLY WEAK SURFACE CONVERGENCE WITH THIS...AND CAPE IS MEAGER. THE
NAM WHICH OFTEN RUNS HIGH ON CAPE IS STRUGGLING TO BREAK 300J/KG
ACROSS THE WESTERN FORECAST AREA...AND HAS MOST OF THAT BEHIND
THIS FIRST LINE -- CLOSER TO THE COLD FRONT. DID KEEP ISOLATED
THUNDER MENTIONED BUT NOT REAL IMPRESSED WITH POTENTIAL FOR
STRONG/SEVERE CONVECTION THIS FAR EAST. WITH DECENT FLOW IN
PLACE...CANNOT RULE OUT GUSTY OUTFLOW WINDS WITH ANY STRONGER
CELLS. PWATS POOL UP TO AROUND 1.25IN WITH THIS PRE-FRONTAL BAND
AS WELL...SO BRIEF MODERATE TO HEAVY RAIN IS POSSIBLE.
TRIED TO SHOW A BREAK BETWEEN THIS PRE-FRONTAL BAND AND THE
SECONDARY BAND WITH THE COLD FRONT...PWATS SHOWING THIS AS WELL
WITH A QUICK DIP UNDER 1.0IN BEFORE RAMPING BACK UP JUST AHEAD OF
THE FRONT. KEPT ISOLATED THUNDER MENTION GOING UNTIL THIS
SECONDARY BAND PASSES...BUT WITH THIS OCCURRING LATE TONIGHT
TIMING IS NOT IDEAL.
LOW LEVEL MOISTURE GETS TRAPPED IN THE LOW LEVELS...AND LINGERS
THROUGH MOST OF FRIDAY. EXPECT LOW STRATUS AND DRIZZLE THROUGH THE
MORNING...GRADUALLY COMING TO AN END FROM WEST TO EAST DURING THE
AFTERNOON.
TEMPERATURE WISE...HELD TEMPS UP TONIGHT UNTIL THE FRONT
PASSES USING A CONSENSUS BLEND...AND THE HRRR AS FAR OUT AS
POSSIBLE. EXPECT ONLY MINIMAL WARMING TOMORROW.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
A PROGRESSIVE PATTERN THIS PERIOD WITH ZONAL FLOW ALOFT. THE
DOMINATING FEATURE THIS WEEKEND WILL BE HIGH PRESSURE THAT WILL
QUICKLY MOVE EASTWARD ACROSS THE AREA FRIDAY NIGHT AND EARLY
SATURDAY. CLOUDS WILL QUICKLY CLEAR OUR FRIDAY NIGHT AS THE HIGH
PRESSURE WITH DRIER AIR MOVES IN...BUT LOW LEVEL MOISTURE THAT GETS
PUSHED SOUTH FRIDAY NIGHT WILL RETURN DURING SATURDAY ON SOUTHEAST
FLOW AS THE HIGH CENTER SHIFTS OFF THE COAST. THE CLOUDS WILL MAINLY
AFFECT EAST FACING SLOPES OF WEST VIRGINIA AND SOUTHWEST VIRGINIA.
HOWEVER NO PRECIP WITH THIS SHALLOW MOISTURE. REMAINDER OF AREA WILL
SEE ABUNDANT SUNSHINE SATURDAY.
WITH INCREASING SOUTHERLY FLOW AND SUNSHINE SATURDAY...LOOK FOR
TEMPERATURES TO REBOUND INTO THE 60S SATURDAY AFTERNOON. EVEN ON
THE EAST FACING SLOPES...TEMPERATURES WILL WARMER DESPITE THE
CLOUDS. CLOUDS WILL AGAIN SHIFT OUT TO THE SOUTH AND EAST SATURDAY
NIGHT AS LOW LEVEL FLOW BECOMES MORE WESTERLY. THIS WILL ALLOW FOR
A DRY AND MILDER NIGHT SATURDAY NIGHT.
THE FORECAST PROBLEM COMES WITH THE NEXT SYSTEM APPROACHING LATE
SUNDAY. THE MODELS CONTINUE TO BE QUITE DIVERGENT ON THE
STRENGTH...TRACK AND SPEED OF THE SURFACE LOW COMING ACROSS THE
CENTRAL PART OF THE NATION. THE EURO MODEL IS MORE WRAPPED UP AND
MUCH SLOWER WITH THIS SYSTEM WHILE MOST OF THE OTHER MODELS ARE MORE
OPEN AND FASTER. WITH A PROGRESSIVE ZONAL FLOW ALOFT SHOWN BY THE
MODELS...THE LESS AMPLIFIED AND FASTER SOLUTION OF THE MAJORITY OF
THE MODELS WOULD SEEM TO BE THE WAY TO GO. THUS...USING GFS AS A
GUIDE. I HAVE CLOUDS INCREASING DURING THE DAY SUNDAY...AND
SCATTERED SHOWERS ARRIVING WEST OF THE OHIO RIVER BY DAYS END.
STILL...LOOK FOR TEMPERATURES ON SOUTHERLY FLOW TO REACH INTO THE
70S MOST AREAS...ESPECIALLY ACROSS THE EASTERN LOW LANDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ANOTHER COLD FRONT WILL MOVE THROUGH THE AREA SUNDAY NIGHT...WITH
SHOWERS LIKELY AS IT DOES SO. HIGH PRESSURE...WITH COOLER...AND
DRIER AIR BEHIND THE FRONT FOR TUESDAY...WITH A GRADUAL WARMING
TREND TOWARDS MID WEEK AS UPPER RIDGE GRADUALLY BUILDS ACROSS THE
AREA...AS AN UPPER TROUGH DEEPENS ACROSS THE CENTRAL UNITED
STATES. THE TROUGH...AND ASSOCIATED LOW PRESSURE SYSTEM WILL MOVE
INTO THE REGION TOWARDS THE END OF THE EXTENDED
PERIOD...GENERATING ADDITIONAL ROUNDS OF SHOWERS AND
THUNDERSTORMS.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
COLD FRONT APPROACHING FROM THE WEST THIS EVENING...WILL DRIVE
TWO AREAS OF SHOWERS IN FROM THE WEST. THE FIRST LATE THIS
AFTERNOON INTO THIS EVENING WELL AHEAD OF THE FRONT...AND THE
SECOND WITH THE FRONT OVERNIGHT. INSTABILITY IS WEAK...BUT DID
INCLUDE VCTS WITH THE FIRST AREA IN THE TRI-STATE...BUT NO WHERE
ELSE. CANNOT RULE OUT AN ISOLATED RUMBLE HOWEVER...AND WILL NEED
TO MONITOR FOR NEED TO MENTION ELSEWHERE. KEPT THINGS MVFR WITH
THE PRECIP...BUT COULD HAVE BRIEF IFR IN HEAVIER SHOWERS. LOW
LEVEL MOISTURE LINGERS THROUGH MOST OF THE DAY FRIDAY...WITH MVFR
IN LOW STRATUS AND DRIZZLE/FOG.
GUSTY SOUTHERLY WINDS TODAY WILL WEAKEN SOME TONIGHT...BECOMING
WESTERLY AND NOT AS STRONG BEHIND THE FRONT AND INTO FRIDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MAY NEED TO ADD TEMPOS FOR THUNDER AND/OR IFR
DEPENDING ON HOW THINGS PROGRESS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H M M M M
HTS CONSISTENCY H H H H H M M M M M M M
BKW CONSISTENCY H H H H H H H H H M M M
EKN CONSISTENCY H H H H H H H H M H M M
PKB CONSISTENCY H H H H H H H M M M M M
CKB CONSISTENCY H H H H H H H M M M M M
AFTER 18Z FRIDAY...
IFR POSSIBLE IN PRECIPITATION SUNDAY NIGHT INTO MONDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/MZ/30
NEAR TERM...MZ
SHORT TERM...JMV
LONG TERM...SL
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
254 PM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT CROSSES TONIGHT. LINGERING LOW LEVEL MOISTURE FRIDAY. HIGH
PRESSURE SYSTEM ARRIVES FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
MAIN FOCUS FOR NEAR TERM FORECAST IS COLD FRONT APPROACHING FROM
THE WEST. CLOUDS MAKING IT INTO THE OHIO RIVER VALLEY NOW AS THE
COLD FRONT ENTERS WESTERN KY/IN. HAVE A PRE-FRONTAL BAND OF
PRECIPITATION STRETCHING FROM WESTERN OHIO THROUGH CENTRAL KY.
THIS BAND WILL MOVE THROUGH LATE THIS AFTERNOON AND THIS EVENING.
ONLY WEAK SURFACE CONVERGENCE WITH THIS...AND CAPE IS MEAGER. THE
NAM WHICH OFTEN RUNS HIGH ON CAPE IS STRUGGLING TO BREAK 300J/KG
ACROSS THE WESTERN FORECAST AREA...AND HAS MOST OF THAT BEHIND
THIS FIRST LINE -- CLOSER TO THE COLD FRONT. DID KEEP ISOLATED
THUNDER MENTIONED BUT NOT REAL IMPRESSED WITH POTENTIAL FOR
STRONG/SEVERE CONVECTION THIS FAR EAST. WITH DECENT FLOW IN
PLACE...CANNOT RULE OUT GUSTY OUTFLOW WINDS WITH ANY STRONGER
CELLS. PWATS POOL UP TO AROUND 1.25IN WITH THIS PRE-FRONTAL BAND
AS WELL...SO BRIEF MODERATE TO HEAVY RAIN IS POSSIBLE.
TRIED TO SHOW A BREAK BETWEEN THIS PRE-FRONTAL BAND AND THE
SECONDARY BAND WITH THE COLD FRONT...PWATS SHOWING THIS AS WELL
WITH A QUICK DIP UNDER 1.0IN BEFORE RAMPING BACK UP JUST AHEAD OF
THE FRONT. KEPT ISOLATED THUNDER MENTION GOING UNTIL THIS
SECONDARY BAND PASSES...BUT WITH THIS OCCURRING LATE TONIGHT
TIMING IS NOT IDEAL.
LOW LEVEL MOISTURE GETS TRAPPED IN THE LOW LEVELS...AND LINGERS
THROUGH MOST OF FRIDAY. EXPECT LOW STRATUS AND DRIZZLE THROUGH THE
MORNING...GRADUALLY COMING TO AN END FROM WEST TO EAST DURING THE
AFTERNOON.
TEMPERATURE WISE...HELD TEMPS UP TONIGHT UNTIL THE FRONT
PASSES USING A CONSENSUS BLEND...AND THE HRRR AS FAR OUT AS
POSSIBLE. EXPECT ONLY MINIMAL WARMING TOMORROW.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
A PROGRESSIVE PATTERN THIS PERIOD WITH ZONAL FLOW ALOFT. THE
DOMINATING FEATURE THIS WEEKEND WILL BE HIGH PRESSURE THAT WILL
QUICKLY MOVE EASTWARD ACROSS THE AREA FRIDAY NIGHT AND EARLY
SATURDAY. CLOUDS WILL QUICKLY CLEAR OUR FRIDAY NIGHT AS THE HIGH
PRESSURE WITH DRIER AIR MOVES IN...BUT LOW LEVEL MOISTURE THAT GETS
PUSHED SOUTH FRIDAY NIGHT WILL RETURN DURING SATURDAY ON SOUTHEAST
FLOW AS THE HIGH CENTER SHIFTS OFF THE COAST. THE CLOUDS WILL MAINLY
AFFECT EAST FACING SLOPES OF WEST VIRGINIA AND SOUTHWEST VIRGINIA.
HOWEVER NO PRECIP WITH THIS SHALLOW MOISTURE. REMAINDER OF AREA WILL
SEE ABUNDANT SUNSHINE SATURDAY.
WITH INCREASING SOUTHERLY FLOW AND SUNSHINE SATURDAY...LOOK FOR
TEMPERATURES TO REBOUND INTO THE 60S SATURDAY AFTERNOON. EVEN ON
THE EAST FACING SLOPES...TEMPERATURES WILL WARMER DESPITE THE
CLOUDS. CLOUDS WILL AGAIN SHIFT OUT TO THE SOUTH AND EAST SATURDAY
NIGHT AS LOW LEVEL FLOW BECOMES MORE WESTERLY. THIS WILL ALLOW FOR
A DRY AND MILDER NIGHT SATURDAY NIGHT.
THE FORECAST PROBLEM COMES WITH THE NEXT SYSTEM APPROACHING LATE
SUNDAY. THE MODELS CONTINUE TO BE QUITE DIVERGENT ON THE
STRENGTH...TRACK AND SPEED OF THE SURFACE LOW COMING ACROSS THE
CENTRAL PART OF THE NATION. THE EURO MODEL IS MORE WRAPPED UP AND
MUCH SLOWER WITH THIS SYSTEM WHILE MOST OF THE OTHER MODELS ARE MORE
OPEN AND FASTER. WITH A PROGRESSIVE ZONAL FLOW ALOFT SHOWN BY THE
MODELS...THE LESS AMPLIFIED AND FASTER SOLUTION OF THE MAJORITY OF
THE MODELS WOULD SEEM TO BE THE WAY TO GO. THUS...USING GFS AS A
GUIDE. I HAVE CLOUDS INCREASING DURING THE DAY SUNDAY...AND
SCATTERED SHOWERS ARRIVING WEST OF THE OHIO RIVER BY DAYS END.
STILL...LOOK FOR TEMPERATURES ON SOUTHERLY FLOW TO REACH INTO THE
70S MOST AREAS...ESPECIALLY ACROSS THE EASTERN LOW LANDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE TO START THE PERIOD WITH A WARM SOUTHWESTERLY FLOW
ACROSS THE AREA...AS UPPER TROUGH DEEPENS ACROSS THE CENTRAL
UNITED STATES. BY LATE SUNDAY INTO MONDAY...A LOW PRESSURE SYSTEM
WILL MOVE INTO THE REGION...SPREADING RAIN...AND ISOLATED
THUNDERSTORMS BACK INTO THE AREA. BEHIND THE SYSTEM...MUCH COOLER
TEMPERATURES FOR TUESDAY...WITH THE POSSIBILITY OF A CHANGE OVER
TO -SHSN ACROSS THE HIGHER TERRAIN MONDAY NIGHT. THE COOLER
WEATHER DOESNT LOOK TO LAST LONG HOWEVER...AS UPPER RIDGING TAKES
HOLD AGAIN BY MID WEEK.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
COLD FRONT APPROACHING FROM THE WEST THIS EVENING...WILL DRIVE
TWO AREAS OF SHOWERS IN FROM THE WEST. THE FIRST LATE THIS
AFTERNOON INTO THIS EVENING WELL AHEAD OF THE FRONT...AND THE
SECOND WITH THE FRONT OVERNIGHT. INSTABILITY IS WEAK...BUT DID
INCLUDE VCTS WITH THE FIRST AREA IN THE TRI-STATE...BUT NO WHERE
ELSE. CANNOT RULE OUT AN ISOLATED RUMBLE HOWEVER...AND WILL NEED
TO MONITOR FOR NEED TO MENTION ELSEWHERE. KEPT THINGS MVFR WITH
THE PRECIP...BUT COULD HAVE BRIEF IFR IN HEAVIER SHOWERS. LOW
LEVEL MOISTURE LINGERS THROUGH MOST OF THE DAY FRIDAY...WITH MVFR
IN LOW STRATUS AND DRIZZLE/FOG.
GUSTY SOUTHERLY WINDS TODAY WILL WEAKEN SOME TONIGHT...BECOMING
WESTERLY AND NOT AS STRONG BEHIND THE FRONT AND INTO FRIDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MAY NEED TO ADD TEMPOS FOR THUNDER AND/OR IFR
DEPENDING ON HOW THINGS PROGRESS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H M M M M
HTS CONSISTENCY H H H H H M M M M M M M
BKW CONSISTENCY H H H H H H H H H M M M
EKN CONSISTENCY H H H H H H H H M H M M
PKB CONSISTENCY H H H H H H H M M M M M
CKB CONSISTENCY H H H H H H H M M M M M
AFTER 18Z FRIDAY...
IFR POSSIBLE IN PRECIPITATION SUNDAY NIGHT INTO MONDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/MZ/30
NEAR TERM...MZ
SHORT TERM...JMV
LONG TERM...SL
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
213 PM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT CROSSES TONIGHT. LINGERING LOW LEVEL MOISTURE FRIDAY. HIGH
PRESSURE SYSTEM ARRIVES FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
MAIN FOCUS FOR NEAR TERM FORECAST IS COLD FRONT APPROACHING FROM
THE WEST. CLOUDS MAKING IT INTO THE OHIO RIVER VALLEY NOW AS THE
COLD FRONT ENTERS WESTERN KY/IN. HAVE A PRE-FRONTAL BAND OF
PRECIPITATION STRETCHING FROM WESTERN OHIO THROUGH CENTRAL KY.
THIS BAND WILL MOVE THROUGH LATE THIS AFTERNOON AND THIS EVENING.
ONLY WEAK SURFACE CONVERGENCE WITH THIS...AND CAPE IS MEAGER. THE
NAM WHICH OFTEN RUNS HIGH ON CAPE IS STRUGGLING TO BREAK 300J/KG
ACROSS THE WESTERN FORECAST AREA...AND HAS MOST OF THAT BEHIND
THIS FIRST LINE -- CLOSER TO THE COLD FRONT. DID KEEP ISOLATED
THUNDER MENTIONED BUT NOT REAL IMPRESSED WITH POTENTIAL FOR
STRONG/SEVERE CONVECTION THIS FAR EAST. WITH DECENT FLOW IN
PLACE...CANNOT RULE OUT GUSTY OUTFLOW WINDS WITH ANY STRONGER
CELLS. PWATS POOL UP TO AROUND 1.25IN WITH THIS PRE-FROTNAL BAND
AS WELL...SO BRIEF MODERATE TO HEAVY RAIN IS POSSIBLE.
TRIED TO SHOW A BREAK BETWEEN THIS PRE-FRONTAL BAND AND THE
SECONDARY BAND WITH THE COLD FRONT...PWATS SHOWING THIS AS WELL
WITH A QUICK DIP UNDER 1.0IN BEFORE RAMPING BACK UP JUST AHEAD OF
THE FRONT. KEPT ISOLATED THUNDER MENTION GOING UNTIL THIS
SECONDARY BAND PASSES...BUT WITH THIS OCCURRING LATE TONIGHT
TIMING IS NOT IDEAL.
LOW LEVEL MOISTURE GETS TRAPPED IN THE LOW LEVELS...AND LINGERS
THROUGH MOST OF FRIDAY. EXPECT LOW STRATUS AND DRIZZLE THROUGH THE
MORNING...GRADUALLY COMING TO AN END FROM WEST TO EAST DURING THE
AFTERNOON.
TEMPERATURE WISE...HELD TEMPS UP TONIGHT UNTIL THE FRONT
PASSES USING A CONSENSUS BLEND...AND THE HRRR AS FAR OUT AS
POSSIBLE. EXPECT ONLY MINIMAL WARMING TOMORROW.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
THE COLD FRONT SHOULD BE EXITING THE MOUNTAINS FIRST THING FRIDAY
MORNING WITH CAA ENSUING. STILL THINKING AN ABUNDANCE OF STRATOCU
WILL THRU THE AFTERNOON HOURS...ESPECIALLY OVER N HALF OF WV. FOR
TEMPS STILL GOING ON THE COOL SIDE OF THE ENVELOPE OVER MOST
AREAS...PARTICULARLY ACROSS N WV. THIS WILL BE A QUICK HITTING
SHOT OF COLD AS WAA ALOFT WILL QUICKLY DEVELOP FRIDAY NIGHT. THIS
WILL ESSENTIALLY SCOUR OUT ANY LINGERING CLOUDS OVER THE N
MOUNTAINS. AS SUCH...A RIDGE/VALLEY SPLIT WAS CODED UP WITH
HILLTOPS AND RIDGES EXPERIENCING A NON DIURNAL TRACE OVERNIGHT.
MOST PLACES SHOULD GET DOWN INTO THE LOWER 30S WITH SOME UPPER 20S
IN THE TYPICAL COLD HOLLOWS. SATURDAY WILL SEE SW FLOW DEVELOP
WITH A CONTINUATION OF WAA. STABLE AIR NEAR THE SURFACE MAY KEEP
HIGHS IN CHECK A BIT BUT STILL ABOVE NORMAL FOR THIS TIME OF
YEAR. ANOTHER RIDGE/VALLEY SPLIT NIGHT SATURDAY NIGHT AMID A
MAINLY CLEAR SKY BUT NOT AS COLD AS PREVIOUS NIGHT. ATTENTION
TURNS TO THE NEXT SYSTEM ON SUNDAY WHICH SHOULD STAY WELL W OF THE
AREA DURING THE DAY. S FLOW WILL STRENGTHEN...RESULTING IN A DAY
IN 70S FOR A GOOD CHUNK OF THE AREA...ALBEIT ON THE WINDY SIDE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE TO START THE PERIOD WITH A WARM SOUTHWESTERLY FLOW
ACROSS THE AREA...AS UPPER TROUGH DEEPENS ACROSS THE CENTRAL
UNITED STATES. BY LATE SUNDAY INTO MONDAY...A LOW PRESSURE SYSTEM
WILL MOVE INTO THE REGION...SPREADING RAIN...AND ISOLATED
THUNDERSTORMS BACK INTO THE AREA. BEHIND THE SYSTEM...MUCH COOLER
TEMPERATURES FOR TUESDAY...WITH THE POSSIBILITY OF A CHANGE OVER
TO -SHSN ACROSS THE HIGHER TERRAIN MONDAY NIGHT. THE COOLER
WEATHER DOESNT LOOK TO LAST LONG HOWEVER...AS UPPER RIDGING TAKES
HOLD AGAIN BY MID WEEK.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
COLD FRONT APPROACHING FROM THE WEST THIS EVENING...WILL DRIVE
TWO AREAS OF SHOWERS IN FROM THE WEST. THE FIRST LATE THIS
AFTERNOON INTO THIS EVENING WELL AHEAD OF THE FRONT...AND THE
SECOND WITH THE FRONT OVERNIGHT. INSTABILITY IS WEAK...BUT DID
INCLUDE VCTS WITH THE FIRST AREA IN THE TRI-STATE...BUT NO WHERE
ELSE. CANNOT RULE OUT AN ISOLATED RUMBLE HOWEVER...AND WILL NEED
TO MONITOR FOR NEED TO MENTION ELSEWHERE. KEPT THINGS MVFR WITH
THE PRECIP...BUT COULD HAVE BRIEF IFR IN HEAVIER SHOWERS. LOW
LEVEL MOISTURE LINGERS THROUGH MOST OF THE DAY FRIDAY...WITH MVFR
IN LOW STRATUS AND DRIZZLE/FOG.
GUSTY SOUTHERLY WINDS TODAY WILL WEAKEN SOME TONIGHT...BECOMING
WESTERLY AND NOT AS STRONG BEHIND THE FRONT AND INTO FRIDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MAY NEED TO ADD TEMPOS FOR THUNDER AND/OR IFR
DEPENDING ON HOW THINGS PROGRESS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H M M M M
HTS CONSISTENCY H H H H H M M M M M M M
BKW CONSISTENCY H H H H H H H H H M M M
EKN CONSISTENCY H H H H H H H H M H M M
PKB CONSISTENCY H H H H H H H M M M M M
CKB CONSISTENCY H H H H H H H M M M M M
AFTER 18Z FRIDAY...
IFR POSSIBLE IN PRECIPITATION SUNDAY NIGHT INTO MONDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...MZ/30
NEAR TERM...MZ
SHORT TERM...30
LONG TERM...SL
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1122 AM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TODAY AND CROSS THE REGION
TONIGHT. DRY HIGH PRESSURE WILL SET UP OVER THE AREA FRIDAY INTO
SATURDAY...BUT WITH GULF AND ATLANTIC MOISTURE RETURNING ON SUNDAY
AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. A COLD FRONT WILL CROSS
THE REGION FROM THE WEST ON MONDAY WITH DRIER CONDITIONS RETURNING
UNTIL MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM EDT THURSDAY...CONTINUING TO MONITOR PROGRESSION OF
UPPER SHORTWAVE ATOP THE ARKLATEX...AS IT RELATES TO DEVELOPING
CONVECTION ACROSS EAST MS AND WESTERN AL. THE COLD FRONT
ASSOCIATED WITH THIS SYSTEM REMAINS JUST WEST OF THE MS RIVER
AT THIS TIME...HOWEVER SHOULD QUICKLY ADVECT EAST THROUGH THE
REMAINDER OF THE MORNING. CLOSER TO HOME...NEAR TERM HIGH RES
GUIDANCE CONTINUES TO FAVOR CONVECTION SLIDING INTO EXTREME
NORTHEAST GA AND EXTREME WESTERN NC/SC AROUND 6-7PM ASSOCIATED
WITH THE SFC TROF AHEAD OF THE FRONTAL AXIS...THEN ANOTHER ROUND
OF CONVECTION JUST AHEAD OF SAID FRONT OVERNIGHT. DONT REALLY
HAVE MUCH CONFIDENCE IN THE STRENGTH/DEPTH OF THE FIRST WAVE AS
BOTH PLAN VIEW AND SOUNDING GUIDANCE FAVOR SURGING DEWPOINTS AHEAD
OF THE FRONT LATER INTO THE OVERNIGHT...WHICH ACTUALLY YIELDS THE
BEST INSTABILITY...DESPITE TIMING OF DAY. AS THE HRRR MOVES THE
INITIAL WAVE OF CONVECTION INTO THE UPPER SAVANNAH RIVER VALLEY
JUST BEFORE SUNSET...12Z NAM SOUNDINGS AT KAND EXHIBIT MODEST
CAPPING WITH POOR MID LEVEL LAPSE RATES. ONCE THE DEWPOINTS
SURGE INTO THE OVERNIGHT...SOUNDINGS THEN FAVOR SLIGHTLY IMPROVED
LAPSE RATES AND THUS INCREASING INSTABILITY. THUS...STILL THINK A
MODEST CU FIELD WILL EXPAND OVER THE AREA THROUGH MORNING/AFTERNOON
WITH CHANCES FOR ISOLATED SHRA POSSIBLE INTO THE EARLY EVENING.
BEYOND THAT...POPS STILL RAMP UP OVER THE WEST AS THE ATMOSPHERE
MOISTENS AND THE FRONT ENCROACHES PROVIDING ADDED LLV CONVERGENCE.
AS FOR CHANGES TO THE FCST...DID TWEAK TEMPERATURES/DEWPOINTS BY
BLENDING IN LATEST CONSHORT YIELDING SAID SURGING DEWPOINTS OVER
THE SAVANNAH RIVER VALLEY THIS EVENING...AND OVER THE REMAINDER OF
THE AREA OVERNIGHT. ALSO INCREASED QPF A TAD ALONG THE ESCARPMENT
PER LATEST WPCQPF...HOWEVER ANY UPSLOPING LOOKS SHORT LIVED AS
THE H85 FLOW VEERS SW RATHER QUICKLY.
PREVIOUS DISCUSSION...A MATURE AND DEEP LOW PRESSURE SYSTEM WILL
TRACK FROM THE MIDWEST TO THE GREAT LAKES THRU TONIGHT. A TRAILING
COLD FRONT WILL CROSS THE TN VALLEY TODAY...AND SHOULD PUSH INTO
THE AREA OVERNIGHT TONIGHT. GUIDANCE IS IN DECENT AGREEMENT THAT
A PRE-FRONTAL BAND OF CONVECTION WILL ENTER THE WESTERN EDGE OF
THE CWFA EARLY THIS EVENING...AND CROSS THE AREA OVERNIGHT. THE
OP MODELS SHOW GENERALLY 100-200 J/KG OF MUCAPE WITH THE LINE
(ALONG AND SOUTH OF THE NC BORDER). EVEN WITH THIS INSTBY...THE
HIGH RES MODELS INDICATE THE THE CONVECTION MAY OUTPACE THE TONGUE
OF UNSTABLE AIR TO OUR WEST...AND HENCE WEAKEN THE ACTIVITY AS IT
CROSSES THE CWFA. GIVEN THE EXPECTED TIMING OF THE PRECIP...AND
THE LACK OF INSTBY CURRENTLY OVER THE CENTRAL GULF STATES...THAT
MAKES SENSE. STILL...THERE WILL BE SOLID ENTRANCE REGION UPPER
JET DIVERGENCE AND LLVL ISENT LIFT WITHIN THE BAND...AND SO LIKELY
TO CATEGORICAL POP STILL LOOKS GOOD TONIGHT. I WILL KEEP THUNDER
MENTION TO MAINLY SLGT CHC TO CHC. TEMPS WILL BE ABOVE NORMAL
AGAIN TODAY...BUT WITH MORE CLOUD COVER AROUND. HIGHS IN THE 60S
MTNS...AND MID-UPR 70S PIEDMONT.
AS FOR SEVERE THREAT...THE NEW DAY 1 SPC CONVECTIVE OUTLOOK STILL
HIGHLIGHTS A SLIGHT RISK OVER THE TN VALLEY AND CENTRAL GULF
STATES...BUT EXPANDED THE MARGINAL RISK TO ABOUT THE WESTERN
THIRD OF THE CWFA. THE MODE OF CONVECTION LOOKS MUDDLED IN THE
CAMS...WITH MAINLY A BAND OF SHOWERS WITH EMBEDDED TSTMS (AS OPPOSED
TO A SOLID QLCS). PERHAPS THEY ARE KEYING IN ON LACK OF INSTBY AND
THE FRONT LOSING STEAM TO KEEP THE FORCING MORE LINEAR. WE WILL
MENTION THUNDER IN THE HWO...WITH THE POTENTIAL FOR A FEW ISOLATED
SEVERE WIND GUSTS...ESP IN THE WEST. IT MAY BE THE CASE THAT THE
HIGH TERRAIN MAY SEE SOME WIND ADV CRITERIA GUSTS WITHIN THE SWLY
LLJ...AS THE SHOWER MOVE IN. GIVEN THE SHORT DURATION...WITH HOLD
OFF ON ANY WIND ADVISORY. TEMPS WILL REMAIN ELEVATED AS THE FRONT
SLOWS ITS PROGRESS OVERNIGHT. LOWS RANGING FROM MID 40S ALONG THE
TN BORDER TO LWR 60S SOUTHEAST OF I-85.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
AS OF 245 AM EDT THURSDAY...THE PASSING COLD FRONT WILL BE SLOWLY
MOVING EAST OF THE AREA ON FRIDAY. THERE IS SOME UNCERTAINTY OVER
HOW QUICKLY THE BACK EDGE OF THE DEEPER MOISTURE WILL CLEAR THE
REGION WITH THE FRONTAL ZONE...BUT THE LATEST NAM APPEARS TO BE A
SLOW OUTLIER IN KEEPING PRECIPITATION CHANCES ACROSS THE REGION
THROUGH MOST OF FRIDAY. THE CURRENT THINKING IS THAT ANY LINGERING
POPS SHOULD CONSIST MAINLY OF MORNING SHOWERS EAST OF INTERSTATE 77
AND ALSO IN MOIST UPSLOPE FLOW OVER THE WESTERN MOUNTAINS.
NEVERTHELESS...THE DEPARTING SURFACE BOUNDARY COULD GET HUNG UP AS
IT APPROACHES THE SOUTHEAST COASTLINE GIVEN THE DEEP LAYER WSW FLOW
ALOFT. POST FROPA TEMPERATURES FRIDAY AFTERNOON SHOULD RUN 5 TO 10
DEGREES ABOVE CLIMO WITH THE LACK OF COLD ADVECTION AND IMPROVING
INSOLATION.
THE PENETRATION OF DRY AIR BEHIND THE FRONT...WITH SURFACE HIGH
PRESSURE BUILDING OVER TO THE NORTH...SHOULD KEEP SATURDAY DRY
DESPITE MODEL HINTS AT WEAK UPGLIDE STRAINING TO RETURN FROM THE
SOUTHEAST. THE FORECAST WILL HEDGE TOWARD A FEW MORE CLOUDS...BUT NO
PRECIPITATION AT THIS POINT. TEMPERATURES WILL BE A CATEGORY OR SO
ABOVE CLIMO...IF WE DO NOT CLOUD BACK UP TOO QUICKLY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 300 AM EDT THURSDAY...THE NUMERICAL MODELS ARE IN BETTER
AGREEMENT WITH THE HANDLING OF THE UPPER TROUGH OVER THE SOUTHERN
PLAINS ON SUNDAY...CROSSING THE SOUTHERN APPALACHIANS ON MONDAY. A
BETTER GULF MOISTURE TAP WILL GET ESTABLISHED SUNDAY AHEAD OF THE
APPROACHING SYSTEM...WITH IMPROVING CHANCES OF UPGLIDE
PRECIPITATION. THE NOSE OF OFFSHORE HIGH PRESSURE COULD LINGER EAST
OF THE APPALACHIANS JUST LONG ENOUGH ON SUNDAY FOR WEAK IN SITU COLD
AIR DAMMING TO GET ESTABLISHED. THE CURRENTLY FEATURED TEMPERATURES
IN THE 60S ACROSS THE NORTHERN TIER WILL NEED QUITE A BIT OF
ADJUSTMENT IF THAT HAPPENS.
LOW PRESSURE ZIPPING NORTHWARD FROM THE GULF OF MEXICO ALONG THE
APPROACHING FRONT WILL HELP TO FOCUS MOISTURE OVER THE AREA SUNDAY
NIGHT...AND FORCING WILL IMPROVE WITH A WEAKLY COUPLED UPPER JET
STRUCTURE OVERHEAD IN ADVANCE OF THE APPROACHING TROUGH. INSTABILITY
WILL ALSO LIKELY WRAP UP ACROSS THE SOUTHEAST PIEDMONT LATER SUNDAY
NIGHT INTO MONDAY MORNING...WITH THUNDERSTORM CHANCES THE HIGHEST
SOUTHEAST OF INTERSTATE 85 JUST AHEAD OF THE PASSING COLD FRONT.
A LOCAL QPF MAXIMUM OF AN INCH OR MORE IS POSSIBLE IN THE BEST
REGION OF SOUTHERN MOUNTAIN UPSLOPE FORCING SUN NIGHT/MON...BUT THIS
SHOULD POSE NO HYDRO ISSUES GIVEN THE DRY ANTECEDENT CONDITIONS.
CLEARING IS EXPECTED THROUGH LATE MONDAY FOLLOWING THE COLD FROPA.
UPPER RIDGING WILL BUILD BACK OVER THE REGION TUE THROUGH WED.
RETURN FLOW AROUND THE OFFSHORE SURFACE HIGH COULD ALLOW ATLANTIC
MOISTURE AND ASSOCIATED CLOUDS TO START BUILDING IN UNDER THE RIDGE
ON WED. ANTICIPATE NEAR CLIMO TEMPERATURES TUE AND WED.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
AT KCLT...DEEPER MOISTURE WILL BEGIN TO WORK IN FROM THE WEST
GRADUALLY THRU THE DAY...WITH SOME LOW VFR CIGS EXPECTED TOWARD
SUNSET. OTHERWISE...SCT-BKN CIRRUS AND A FEW CONVECTIVE CUMULUS THRU
THE DAY WITH S WINDS BECOMING SW AND GUSTY BY MIDDAY. GUIDANCE STILL
IN AGREEMENT THAT A BAND OF CONVECTION AHEAD OF A COLD FRONT WILL
CROSS THE MTNS THIS EVENING AND WEAKEN AS IT APPROACHES KCLT. STILL
THINK THERE WILL BE PREVAILING SHRA AND A CHC FOR TSRA TO WARRANT A
PROB30. BEST GUESS ON TIMING IS BETWEEN 4-7Z. THE COLD FRONT WILL
SLOW AS IT CROSSES THE MTNS...AND WITH THE -RA MOVING THRU...SHOULD
SEE AT LEAST MVFR CIGS AND/OR VSBY LATE TONIGHT.
ELSEWHERE...SIMILAR TO KCLT ABOVE. THE LOW VFR CIGS HAVE
DISSIPATED...AS FLOW REMAINS SSW...SLOWING THE GULF MOISTURE FROM
ADVANCING EASTWARD. STILL EXPECT GRADUAL INCREASE IN CU THRU THE DAY
FROM WEST TO EAST...AS A COLD FRONT APPROACHES FROM THE WEST. A
FRONTAL BAND OF SHRA/TSRA IS EXPECTED TO CROSS THE TN VALLEY
TODAY...AND REACH KAVL AROUND 1Z (ALTHO SOME SWLY UPSLOPE LIGHT SHRA
MAY DEVELOP EARLIER). THE PIEDMONT TIMING IS LESS CERTAIN...BUT
EXPECT TO BE MOVING IN AROUND 2-4Z. WINDS WILL FAVOR A S TO SW
DIRECTION THRU THE PERIOD...WITH GUSTS DURING MOST OF THE DAYLIGHT
HOURS...AND PERHAPS AGAIN LATE THIS EVENING AS FRONT APPROACHES. THE
FRONT WILL BE SLOW TO CROSS THE MTNS...AND SO LINGERING LOW CIGS
AND/OR VSBY IS EXPECTED EVEN BEHIND THE SHRA LATE TONIGHT.
OUTLOOK...DRY HIGH PRESSURE WILL TRY TO PUSH IN FROM THE NORTH ON
FRIDAY...BUT THE FRONT WILL STALL NOT FAR SOUTH OF THE
REGION...WHICH MAY KEEP A CHC FOR CLOUDS/PRECIP TO HANG AROUND THIS
WEEKEND.
CONFIDENCE TABLE...
15-21Z 21-03Z 03-09Z 09-12Z
KCLT HIGH 100% HIGH 100% MED 77% MED 77%
KGSP HIGH 100% HIGH 100% MED 69% MED 75%
KAVL HIGH 100% HIGH 94% LOW 51% MED 67%
KHKY HIGH 100% HIGH 100% MED 62% HIGH 83%
KGMU HIGH 100% HIGH 100% MED 73% MED 70%
KAND HIGH 100% HIGH 100% LOW 52% MED 71%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/CDG
SHORT TERM...HG
LONG TERM...HG
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1157 PM CDT WED MAR 23 2016
.UPDATE...
UPDATED FOR THE 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 943 PM CDT WED MAR 23 2016/
UPDATE...
WINDS HAD WEAKENED SOME OVER THE MIDSOUTH FOLLOWING SUNSET... BUT
REMAINED OCCASIONALLY GUSTY ALONG AND WEST OF THE MS RIVER.
CONSIDERED EARLIER DROPPING THE WIND ADVISORY...BUT NAM AND GFS
LAMP GUIDANCE INDICATE A POTENTIAL RETURN TO ADVISORY LEVEL WINDS
AFTER 4 AM...WITH THE APPROACH OF A SURFACE PRESSURE TROF. AN
EARLIER FORECAST UPDATE INCLUDED THUNDERSTORM TIMING ADJUSTMENTS.
00Z NAM AND 01Z HRRR MODEL RUNS WERE IN GOOD AGREEMENT IN
DEVELOPING PREFRONTAL ELEVATED SHOWERS DURING THE OVERNIGHT. BEST
THUNDER POTENTIAL WILL LIKELY ARRIVE OVER EAST AR / NORTHWEST MS
BY 6 AM. THE NAM SHOWED A SHARPLY DEFINED SHORTWAVE TROF ROTATING
THROUGH SOUTHERN MO...AROUND THE BASE OF THE UPPER LOW SHORTLY
AFTER SUNRISE. THIS FEATURE WILL SERVE TO SHARPEN CONVECTIVE FOCUS
OVER WEST TN DURING THE DAYLIGHT MORNING HOURS. TO THE SOUTH... A
SUBTLER SHORTWAVE IS DEPICTED EJECTING FROM THE ARKLATEX INTO THE
NORTH MS BY MIDDAY THURSDAY. THIS LATER FEATURE WILL LIKELY
ENCOUNTER GREATER INSTABILITY OVER NORTHEAST MS...UP TO 1500 J/KG
BY MIDMORNING.
NO ADDITIONAL INFORMATION ON THE STATUS OF THE COLUMBUS AFB
RADAR...KGWX.
CURRENT FORECAST ON TRACK...WITH NO ADDITIONAL CHANGES AT THIS
TIME.
PWB
PREV DISCUSSION... /ISSUED 634 PM CDT WED MAR 23 2016/
DISCUSSION...
AN UPPER LEVEL LOW PRESSURE SYSTEM OVER WESTERN KANSAS THIS
AFTERNOON WILL LIFT OUT TO THE NORTHEAST THROUGH THURSDAY. AS IT
DOES SO...A SHORTWAVE WILL ROTATE THROUGH THE BASE OF THE TROUGH
AND ROTATE ACROSS THE MID SOUTH THURSDAY. STRONG AND GUSTY
SOUTHERLY WINDS SHOULD CONTINUE OVERNIGHT AHEAD OF THIS
SYSTEM...THEREFORE WILL LEAVE THE WIND ADVISORY IN PLACE EVEN
THOUGH IT REMAINS BORDERLINE. SHOWERS AND THUNDERSTORMS SHOULD
DEVELOP ACROSS THE ARKLATEX LATER THIS EVENING AND MOVE INTO
WESTERN SECTIONS OF THE MID SOUTH AFTER MIDNIGHT. INSTABILITY
SHOULD WANE TONIGHT ACROSS OUR AREA SO ANY SEVERE STORMS OVER THE
ARKLATEX SHOULD WEAKEN PRIOR TO REACHING OUR CWA.
AS THE SHORTWAVE ROTATES ACROSS THE REGION...MID LEVEL LAPSE RATES
SHOULD STEEPEN TO BETWEEN 6.5 AND 7.0 C/KM OVER TOP OF A PLUME OF
SURFACE DEWPOINTS RISING INTO THE LOWER 60S ACROSS NORTHEAST
MISSISSIPPI BY EARLY THURSDAY AFTERNOON. AS SURFACE HEATING
COMMENCES THIS SHOULD GENERATE MODEST INSTABILITY WITH CAPE
RANGING FROM 500-1000 J/KG OVER THESE LOCATIONS. THERE REMAINS
MODEL DISAGREEMENT BETWEEN THE LATEST 12Z RUNS...WITH THE NAM AND
TO A LESSER DEGREE THE GFS ON THE HIGHER END OF INSTABILITY WITH
THE ECMWF KEEPING CAPES LESS THAN 500 J/KG. A SLIGHT RISK FOR
SEVERE WEATHER ON THURSDAY STRETCHES ACROSS NORTHEAST MISSISSIPPI
INTO WEST TENNESSEE. THE MOST LIKELY LOCATIONS TO EXPERIENCE
SEVERE STORMS TOMORROW SHOULD BE ACROSS NORTHEAST MISSISSIPPI
WHERE INSTABILITY IS GREATEST. ALL OF THE MODEL GUIDANCE SUGGESTS
STRONG WIND SHEAR THROUGH THE ATMOSPHERE WITH A TENDENCY FOR LOW
LEVEL VEERING OF THE WINDS THROUGH THE DAY. THIS SHEAR IS MORE
THAN SUFFICIENT TO SUPPORT ORGANIZED SEVERE STORMS WHERE IT ALIGNS
WITH THE BEST INSTABILITY. THE PRIMARY THREATS AT THIS TIME APPEAR
TO BE DAMAGING WINDS AND ISOLATED TORNADOES. SHOWERS AND
THUNDERSTORMS SHOULD SHIFT EAST OF THE MID SOUTH BY THURSDAY
EVENING.
HIGH PRESSURE WILL BUILD BACK INTO THE REGION FRIDAY WITH A RETURN
TO DRY WEATHER AND COOLER TEMPERATURES. THIS HIGH PRESSURE WILL
SHIFT EAST BY THE WEEKEND WITH WARMER TEMPERATURES EXPECTED.
ANOTHER SHORTWAVE WILL MOVE ACROSS THE REGION SUNDAY AND SUNDAY
NIGHT WITH ADDITIONAL STORM CHANCES. ANOTHER BRIEF COOL DOWN IS
ANTICIPATED MONDAY BEFORE WARMING BACK TO NEAR OR SLIGHTLY ABOVE
AVERAGE TEMPERATURES THROUGH THE MIDDLE OF NEXT WEEK.
JLH
&&
.AVIATION...
06Z TAF CYCLE
VFR CONDITIONS WILL CONTINUE FOR A FEW MORE HOURS. CEILINGS WILL
DROP TO MVFR LEVELS EARLY THURSDAY MORNING WITH A RETURN TO VFR
CONDITIONS IN THE AFTERNOON. SHOWERS AND THUNDERSTORMS WILL MOVE
INTO WESTERN SECTIONS OF THE FORECAST AREA BEFORE SUNRISE AND WILL
PUSH EAST WITH ACTIVITY EXITING THE EASTERN PART OF THE FORECAST
AREA BY LATE AFTERNOON. WINDS WILL BE MAINLY FROM THE SOUTH AT 15
TO 20 KNOTS WITH OCCASIONAL HIGHER GUSTS. WINDS WILL BECOME MORE
WESTERLY BY THURSDAY AFTERNOON AND THEN WILL BE FROM THE NORTHWEST
IN THE EVENING.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR COAHOMA-DESOTO-PANOLA-
QUITMAN-TALLAHATCHIE-TATE-TUNICA.
TN...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR DYER-LAKE-LAUDERDALE-
OBION-SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1146 PM CDT WED MAR 23 2016
.AVIATION...
SHOWERS AND THUNDERSTORMS WERE DEVELOPING ALONG A COLD FRONT THAT
WAS MOVING THROUGH THE CENTRAL PART OF THE STATE AT 0430Z. TWEAKED
THE TIMING OF THE FRONTAL PASSAGE AFTER COMPARING THE CURRENT
RADAR WITH THE HIGH RESOLUTION MODELS. BOTH THE RAP13 AND HRRR ARE
CLOSE WITH THE CURRENT WIND SHIFT OUT WEST AND THE FRONTAL PASSAGE
THROUGH SE TEXAS.
SINCE THE MODELS ARE CONSISTENT IN ERODING THE STRONG INVERSION AT
850 MB LATER TONIGHT...DO EXPECT A TWO TO THREE-HOUR PERIOD OF
SHOWERS WITH ISOLATED THUNDERSTORMS AHEAD OF THE FRONTAL PASSAGE.
THE BREEZY WINDS AHEAD OF THE FRONT WILL LIKELY DIMINISH BEFORE
BECOMING SOUTHWEST AND WEST AHEAD OF THE FRONT...AND THEN
NORTHWEST AND BECOMING BREEZY AGAIN BEHIND THE FRONT DURING THE
DAY ON THURSDAY. AM EXPECTING AT LEAST MVFR CONDITIONS AHEAD OF
THE FRONT WITH A SLIGHT CHANCE THAT IFR CONDITIONS COULD DEVELOP
IN THE STRONGER STORMS AND HEAVIER SHOWERS. THERE IS ALSO A
MARGINAL CHANCE FOR AN ISOLATED STRONG OR EVEN SEVERE THUNDERSTORM
WITH WIND AND HAIL THE MAIN THREATS...MAINLY FROM METRO HOUSTON
NORTH TO KCLL AND KUTS.
40
&&
.PREV DISCUSSION... /ISSUED 901 PM CDT WED MAR 23 2016/
UPDATE...
AT 700 PM...DEEP LOW PRESSURE WAS LOCATED OVER NE KANSAS. A
PRE FRONTAL TROUGH EXTENDED FROM THE LOW INTO NORTH CENTRAL TEXAS
AND A COLD FRONT TRAILED TO THE WEST EXTENDING FROM THE SFC LOW
ACROSS THE TEXAS PANHANDLE. 00Z SOUNDINGS FROM CRP AND LCH
CONTINUE TO SHOW A STOUT CAP IN PLACE NEAR 850 MB. 850 MB DEW
POINTS ARE AROUND 10 C BUT MOISTURE LEVELS DRY OUT QUICKLY AT 700
MB. AT 300 MB...A DEEP UPPER LOW WAS SPINNING OVER THE
KANSAS/NEBRASKA WITH A 90-100 KT JET TO THE E-SE OF THE LOW. WEAK
DIVERGENCE IS NOTED OVER NE TEXAS.
THE SPEED MAX ON THE EAST SIDE OF LOW WILL MOVE NE TONIGHT AND SE
TX WILL LIE IN A RIGHT REAR QUAD BETWEEN 06-12Z WHICH IS THE SAME
TIME THE COLD FRONT WILL BE CROSSING THE AREA. WATER VAPOR IMAGERY
SHOWS A DISTURBANCE OVER NORTH CENTRAL MEXICO AND THIS FEATURE
SHOULD ARRIVE LATER TONIGHT AND WILL LIKELY HELP TRIGGER
SHRA/TSRA. RAP FCST SOUNDINGS SHOW PW VALUES SURGING TO 1.72 INCHES
WITH A K INDEX OF 39 AT 10Z. THE STRONG CAPPING INVERSION IN
PLACE MAGICALLY DISAPPEARS BETWEEN 07-08Z AND MAYBE THIS IS DUE TO
THE IMPROVING JET DYNAMICS. ALL SHORT TERM GUIDANCE IS BULLISH
WITH RAIN CHANCES OVERNIGHT SO RAISED POPS TO 80 PERCENT OVER THE
CWA. IF THE CAP HOLDS...THE AREA WILL PROBABLY GET JUST A BROKEN
LINE OF WEAK SHOWERS. CAPE/SHEAR LOOK LIMITED SO NOT EXPECTING
MUCH IN THE WAY OF SEVERE WEATHER BUT ONCE THE CAP ERODES...THERE
COULD BE SOME ISOLATED STRONG TO SEVERE STORMS ESPECIALLY TO THE
NE. CONDITIONS SHOULD DRY OUT QUICKLY ON THURSDAY IN THE WAKE OF
THE FRONT WITH SLIGHTLY COOLER TEMPS. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 56 66 44 71 51 / 80 20 0 0 10
HOUSTON (IAH) 62 69 47 72 52 / 80 30 0 0 10
GALVESTON (GLS) 66 68 54 66 60 / 60 60 0 0 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 AM CDT THURSDAY FOR
THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT ADVISORY UNTIL 4 AM CDT THURSDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20
TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1145 PM EDT FRI MAR 25 2016
.SYNOPSIS...
HIGH PRESSURE WILL BUILD NORTH THROUGH SATURDAY. THE NEXT COLD
FRONT APPROACHES THE REGION LATE SUNDAY NIGHT AND CROSSES THROUGH
THE REGION DURING THE DAY MONDAY. TUESDAY AND WEDNESDAY WILL BE
DRY BEHIND THIS FRONT UNDER HIGH PRESSURE. ANOTHER COLD FRONT WILL
CROSS THE REGION ON THURSDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 1135 PM EDT FRIDAY...
STILL SEEING LINGERING MOISTURE WITH FRONTAL BOUNDARY OVER
SOUTHSIDE VA INTO NC. MAY SEE AN ISOLATED SHOWERS EAST OF DANVILLE
AND REIDSVILLE THROUGH 1AM. OTHERWISE LOOKING AT STRUGGLE TO CLEAR
OUT EAST WITH FRONT SLOW TO MOVE AND HIGH CLOUDS POURING IN FROM
THE SOUTHERLY FLOW ALOFT. WILL SEE SOME CLEARING WITH MORE CLOUDS
ARRIVING TOWARD DAWN. THE WEST WILL SEE THE LOWER CLOUDS STAY
AROUND ON THE WRN SLOPES OF SE WV TO FAR SW VA TIL 4AM THEN CLEAR
SOME TOWARD DAWN.
PREVIOUS DISCUSSION FROM LATE AFTERNOON...
FRONTAL BOUNDARY SITUATED FROM WRN NC NORTHEAST TO THE TIDEWATER OF
VIRGINIA. SOME SHOWERS STILL LINGERING OVER SOUTHSIDE VA INTO THE
NC PIEDMONT. THE 18Z LOCAL WRF AND 21Z HRRR HANDLED THIS PRETTY
WELL SO KEEPING LOW CHANCE/SCATTERED POPS IN THE SOUTHEAST
FORECAST AREA FROM THE TRIAD OF NC TO THE DANVILLE SOUTH BOSTON
VICINITY TIL LATE EVENING...THEN SEEING A DRYING TREND. SKIES WILL
BE CLEARING SOMEWHAT OVER THE MIDDLE PART OF THE CWA WITH HIGH
CLOUDS THINNING OUT.
PREVIOUS VALID DISCUSSION...
IN THE WAKE OF THIS FRONT...HIGH PRESSURE BUILDS DOWN THE MID-
ATLANTIC REGION...ALLOWING SFC WINDS TO VEER TO THE
EAST/NORTHEAST. ABOVE THE SFC...850MB WINDS BACK TO THE SOUTH
HELPING TO PUSH LOW LEVEL MOISTURE/CLOUDS BACK INTO THE SOUTHERN
PORTION OF OUR FORECAST AREA AND KEEPING TEMPS ON THE WARM SIDE OF
GUIDANCE. MEANWHILE...ACROSS THE MOUNTAINS...AREAS OF CLEARING AND
DEW POINTS IN THE 30S WILL ALLOW LOWS TO FALL INTO THE MID-UPPER
30S. HOWEVER...NO FROST OR FREEZING CONDITIONS ARE EXPECTED FOR
AREAS IN AREAS WHERE THE GROWING SEASON HAS BEGUN.
DROPPED HIGHS SEVERAL DEGREES ON SATURDAY AS THE HIGH PRESSURE WEDGE
TAKES FIRM HOLD OVER OUR FORECAST AREA...KEEPING CLOUDS IN PLACE.
FORECAST MODELS ALSO INCREASE ISENTROPIC LIFT AT THE 295/300K SFCS
DURING THE AFTERNOON SATURDAY AND WOULD NOT BE SURPRISED TO SEE
AREAS OF LIGHT RAIN TO DEVELOP...ESPECIALLY SOUTH OF HIGHWAY
460...AS LOW LEVEL THETA-E RIDGE NOSES INTO THE REGION.
THEREFORE...INTRODUCED SMALL POPS FOR THIS AREA.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 245 PM EDT FRIDAY...
AT 00Z SUNDAY A LOW WILL BE OFF THE COAST WITH A SURFACE HIGH OVER
THE CANADIAN MARITIMES PLACING THE REGION UNDER AN EASTERLY WEDGE
FLOW. GFS PREVIOUSLY HAD A SURFACE LOW RUNNING ACROSS THE OHIO
VALLEY SUNDAY BUT THE NEW 12Z RUN NOW HAS THE LOW UP ACROSS THE
GREAT LAKES. REGARDLESS...THERE WILL BE A TRAILING COLD FRONT THAT
WILL CROSS THE REGION DURING THE DAY MONDAY. ANOTHER PIECE OF ENERGY
WILL RIDE THE COAST AND WILL LIKELY ROB US SOMEWHAT FOR
RAINFALL...BUT STILL EXPECT THE REGION TO GET ABOUT A TENTH TO A
QUARTER INCH OF QPF. AFTER THE FRONTAL PASSAGE...HIGH PRESSURE WILL
BUILD IN BRINING DRIER CONDITIONS TO THE REGION.
EASTERLY FLOW WILL KEEP SURFACE TEMPS FAIRLY UNIFORM ACROSS THE
REGION ON SUNDAY WITH HIGHS IN THE LOW TO MID 60S. MONDAY WILL BRING
A COOL DOWN TO THE MOUNTAINS WITH HIGHS IN THE MID TO UPPER 50S BUT
A DOWNSLOPING FLOW SHOULD STILL KEEP AREAS EAST OF THE BLUE RIDGE IN
THE MID TO UPPER 60S ON MONDAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 245 PM EDT FRIDAY...
TUESDAY AND WEDNESDAY WILL BE DRY AND PLEASANT DAYS AS THE REGION
REMAINS UNDER THE INFLUENCE OF A SURFACE HIGH THAT WILL SLOWLY DRIFT
FROM SOUTHERN ONTARIO SOUTHEAST TO THE NEW ENGLAND STATES. MEANWHILE
A SURFACE LOW ACROSS THE NORTHERN PLAINS WILL BEGIN TO DEEPEN AS IT
MOVES E/NE INTO SOUTHERN CANADA. A COLD FRONT ASSOCIATED WITH THIS
SYSTEM WILL CROSS OUR AREA ON THURSDAY BRINGING SHOWERS AND POSSIBLY
THUNDERSTORMS. ON FRIDAY ADDITIONAL SHOWERS ARE POSSIBLE AS A
SURFACE LOW DEVELOPS ACROSS THE SOUTHEAST STATES AND SKIRTS JUST TO
OUR EAST BY FRIDAY EVENING. SURFACE TEMPS DURING THIS PERIOD WILL BE
NORMAL TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
AS OF 745 PM EDT FRIDAY...
COMPLEX WEATHER PATTERN EVOLVING THROUGH THE TAF VALID PERIOD THAT
WILL LEAD TO DETERIORATING AVIATION CONDITIONS...ESPECIALLY JUST
BEYOND THE TAF VALID PERIOD.
FRONT SYSTEM THAT MOVED THROUGH THE REGION EARLIER TODAY HAS
STALLED TO OUR SOUTHEAST. A DISTURBANCE NOTED ACROSS SOUTHEAST GA
WILL RIDE ALONG THE FRONTAL BOUNDARY AND SPREAD MOISTURE BACK INTO
THE REGION FROM THE S/SE OVERNIGHT INTO SATURDAY. A STRONGER
WEATHER SYSTEM WILL MOVE INTO THE REGION FROM THE SOUTHWEST LATER
ON SUNDAY. MOISTURE WILL BE ON THE INCREASE THROUGH THE PERIOD.
ALREADY NOTING SOME RAIN SHOWERS PERSISTING NEAR A SURFACE
CONVERGENCE BOUNDARY NEAR KDAN. LOOKING AT RADAR AND HRRR
TRENDS...THESE WILL LIKELY CONTINUE THROUGH THE EVENING AND WILL
NEED TO WATCH FOR ANY SIGNIFICANT REDUCTIONS TO VSBY/CIG.
GENERALLY LOOKING AT A LOW END VFR CIG AROUND KDAN OVERNIGHT WITH
VFR CIGS ELSEWHERE. UPSLOPE FLOW ACROSS THE ALLEGHANYS WILL BE
ENDING SOON...SO THE EASTERN EDGE OF ASSOCIATED CLOUDS ACROSS
EASTERN WV HAVE BEEN ERODING DURING THE PAST FEW HOURS AND HAVE
NOW LEFT KBLF...ALTHOUGH STILL HANGING IN AT KLWB.
WEDGE DEVELOPMENT WILL RESULT IN WINDS COMING AROUND TO THE E-SE
THROUGH THE DAY SATURDAY AND LOW-LEVEL MOISTURE WILL RETURN IN
EARNEST FROM THE SOUTHEAST. LOW END VFR CIGS ARE EXPECTED FROM
KDAN-KLYH AND KROA BY MID-LATE MORNING...CREEPING NORTHWEST TOWARD
KBCB/KBLF/KLWB BY EARLY TO MID-AFTERNOON. CIGS COULD TREND TOWARD
HIGH END MVFR BY 00Z SUN.
VISIBILITY IS NOT EXPECTED TO BE MUCH OF CONCERN THROUGH THIS TAF
VALID PERIOD...ALTHOUGH SOME BR POSSIBLE AT KLWB AND PERHAPS EVEN
KBCB IN THE 08Z-13Z TIME FRAME AND -SHRA POSSIBLY REDUCING
VISIBILITY AT KDAN WITH LIGHT BR LATELY. CONFIDENCE IS LOW IN
EITHER OF THESE OCCURRING.
WINDS WILL VEER TO THE NORTHEAST OVERNIGHT...THEN EAST-SOUTHEAST
SATURDAY AS A WEDGE DEVELOPS AND HIGH PRESSURE MOVES OFF THE MID-
ATLANTIC COAST. SPEEDS MOSTLY 5-8KTS THROUGH THE PERIOD...BUT
SLIGHTLY HIGHER WITH LOW END GUSTS POSSIBLE KLYH-KDAN AFT 14Z SAT.
MEDIUM CONFIDENCE IN CIGS THROUGH THE TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN VSBYS THROUGH THE TAF VALID PERIOD.
MEDIUM CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID PERIOD.
EXTENDED DISCUSSION...
CIGS WILL CONTINUE TO LOWER AFT 00Z SUNDAY AND MOST AREAS WILL SEE
MVFR-IFR CIGS DEVELOP BY SUNDAY MORNING. THIS WILL CONTINUE
INTO EARLY SUNDAY AFTERNOON BEFORE POTENTIALLY SCATTERING OUT
FROM THE WEST AS THE WEDGE RETREATS NORTHEAST. BY SUNDAY
EVENING...AN UPPER TROUGH AND ASSOCIATED FRONTAL SYSTEM WILL BE
APPROACHING FROM THE WEST WITH MVFR-IFR CIGS/VSBYS LIKELY
OVERNIGHT IN RAIN SHOWERS FROM WEST TO EAST. BREEZY AND COOLER
CONDITIONS WILL FOLLOW FOR THE FIRST PART OF NEXT WEEK AS HIGH
PRESSURE BUILDS INTO THE REGION ALLOWING VFR CONDITIONS TO RETURN
BY MONDAY AFTERNOON. THE POSSIBLE DELAYED EXCEPTION WILL BE ACROSS
THE UPSLOPE AREAS OF WV WHERE LOW CLOUDS AND MVFR CIGS COULD
LINGER INTO MONDAY AFTERNOON.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...CF
NEAR TERM...PH/WP
SHORT TERM...CF
LONG TERM...CF
AVIATION...PH/RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
810 PM EDT FRI MAR 25 2016
.SYNOPSIS...
HIGH PRESSURE WILL BUILD NORTH OF THE AREA LATER TODAY THROUGH
SATURDAY. THE NEXT COLD FRONT APPROACHES THE REGION LATE SUNDAY
NIGHT AND CROSSES THROUGH THE REGION DURING THE DAY MONDAY.
TUESDAY AND WEDNESDAY WILL BE DRY BEHIND THIS FRONT UNDER HIGH
PRESSURE. ANOTHER COLD FRONT WILL CROSS THE REGION ON THURSDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 745 PM EDT FRIDAY...
FRONTAL BOUNDARY SITUATED FROM WRN NC NORTHEAST TO THE TIDEWATER OF
VIRGINIA. SOME SHOWERS STILL LINGERING OVER SOUTHSIDE VA INTO THE
NC PIEDMONT. THE 18Z LOCAL WRF AND 21Z HRRR HANDLED THIS PRETTY
WELL SO KEEPING LOW CHANCE/SCATTERED POPS IN THE SOUTHEAST
FORECAST AREA FROM THE TRIAD OF NC TO THE DANVILLE SOUTH BOSTON
VICINITY TIL LATE EVENING...THEN SEEING A DRYING TREND. SKIES WILL
BE CLEARING SOMEWHAT OVER THE MIDDLE PART OF THE CWA WITH HIGH
CLOUDS THINNING OUT.
PREVIOUS VALID DISCUSSION...
IN THE WAKE OF THIS FRONT...HIGH PRESSURE BUILDS DOWN THE MID-
ATLANTIC REGION...ALLOWING SFC WINDS TO VEER TO THE
EAST/NORTHEAST. ABOVE THE SFC...850MB WINDS BACK TO THE SOUTH
HELPING TO PUSH LOW LEVEL MOISTURE/CLOUDS BACK INTO THE SOUTHERN
PORTION OF OUR FORECAST AREA AND KEEPING TEMPS ON THE WARM SIDE OF
GUIDANCE. MEANWHILE...ACROSS THE MOUNTAINS...AREAS OF CLEARING AND
DEW POINTS IN THE 30S WILL ALLOW LOWS TO FALL INTO THE MID-UPPER
30S. HOWEVER...NO FROST OR FREEZING CONDITIONS ARE EXPECTED FOR
AREAS IN AREAS WHERE THE GROWING SEASON HAS BEGUN.
DROPPED HIGHS SEVERAL DEGREES ON SATURDAY AS THE HIGH PRESSURE WEDGE
TAKES FIRM HOLD OVER OUR FORECAST AREA...KEEPING CLOUDS IN PLACE.
FORECAST MODELS ALSO INCREASE ISENTROPIC LIFT AT THE 295/300K SFCS
DURING THE AFTERNOON SATURDAY AND WOULD NOT BE SURPRISED TO SEE
AREAS OF LIGHT RAIN TO DEVELOP...ESPECIALLY SOUTH OF HIGHWAY
460...AS LOW LEVEL THETA-E RIDGE NOSES INTO THE REGION.
THEREFORE...INTRODUCED SMALL POPS FOR THIS AREA.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 245 PM EDT FRIDAY...
AT 00Z SUNDAY A LOW WILL BE OFF THE COAST WITH A SURFACE HIGH OVER
THE CANADIAN MARITIMES PLACING THE REGION UNDER AN EASTERLY WEDGE
FLOW. GFS PREVIOUSLY HAD A SURFACE LOW RUNNING ACROSS THE OHIO
VALLEY SUNDAY BUT THE NEW 12Z RUN NOW HAS THE LOW UP ACROSS THE
GREAT LAKES. REGARDLESS...THERE WILL BE A TRAILING COLD FRONT THAT
WILL CROSS THE REGION DURING THE DAY MONDAY. ANOTHER PIECE OF ENERGY
WILL RIDE THE COAST AND WILL LIKELY ROB US SOMEWHAT FOR
RAINFALL...BUT STILL EXPECT THE REGION TO GET ABOUT A TENTH TO A
QUARTER INCH OF QPF. AFTER THE FRONTAL PASSAGE...HIGH PRESSURE WILL
BUILD IN BRINING DRIER CONDITIONS TO THE REGION.
EASTERLY FLOW WILL KEEP SURFACE TEMPS FAIRLY UNIFORM ACROSS THE
REGION ON SUNDAY WITH HIGHS IN THE LOW TO MID 60S. MONDAY WILL BRING
A COOL DOWN TO THE MOUNTAINS WITH HIGHS IN THE MID TO UPPER 50S BUT
A DOWNSLOPING FLOW SHOULD STILL KEEP AREAS EAST OF THE BLUE RIDGE IN
THE MID TO UPPER 60S ON MONDAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 245 PM EDT FRIDAY...
TUESDAY AND WEDNESDAY WILL BE DRY AND PLEASANT DAYS AS THE REGION
REMAINS UNDER THE INFLUENCE OF A SURFACE HIGH THAT WILL SLOWLY DRIFT
FROM SOUTHERN ONTARIO SOUTHEAST TO THE NEW ENGLAND STATES. MEANWHILE
A SURFACE LOW ACROSS THE NORTHERN PLAINS WILL BEGIN TO DEEPEN AS IT
MOVES E/NE INTO SOUTHERN CANADA. A COLD FRONT ASSOCIATED WITH THIS
SYSTEM WILL CROSS OUR AREA ON THURSDAY BRINGING SHOWERS AND POSSIBLY
THUNDERSTORMS. ON FRIDAY ADDITIONAL SHOWERS ARE POSSIBLE AS A
SURFACE LOW DEVELOPS ACROSS THE SOUTHEAST STATES AND SKIRTS JUST TO
OUR EAST BY FRIDAY EVENING. SURFACE TEMPS DURING THIS PERIOD WILL BE
NORMAL TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 745 PM EDT FRIDAY...
COMPLEX WEATHER PATTERN EVOLVING THROUGH THE TAF VALID PERIOD THAT
WILL LEAD TO DETERIORATING AVIATION CONDITIONS...ESPECIALLY JUST
BEYOND THE TAF VALID PERIOD.
FRONT SYSTEM THAT MOVED THROUGH THE REGION EARLIER TODAY HAS
STALLED TO OUR SOUTHEAST. A DISTURBANCE NOTED ACROSS SOUTHEAST GA
WILL RIDE ALONG THE FRONTAL BOUNDARY AND SPREAD MOISTURE BACK INTO
THE REGION FROM THE S/SE OVERNIGHT INTO SATURDAY. A STRONGER
WEATHER SYSTEM WILL MOVE INTO THE REGION FROM THE SOUTHWEST LATER
ON SUNDAY. MOISTURE WILL BE ON THE INCREASE THROUGH THE PERIOD.
ALREADY NOTING SOME RAIN SHOWERS PERSISTING NEAR A SURFACE
CONVERGENCE BOUNDARY NEAR KDAN. LOOKING AT RADAR AND HRRR
TRENDS...THESE WILL LIKELY CONTINUE THROUGH THE EVENING AND WILL
NEED TO WATCH FOR ANY SIGNIFICANT REDUCTIONS TO VSBY/CIG.
GENERALLY LOOKING AT A LOW END VFR CIG AROUND KDAN OVERNIGHT WITH
VFR CIGS ELSEWHERE. UPSLOPE FLOW ACROSS THE ALLEGHANYS WILL BE
ENDING SOON...SO THE EASTERN EDGE OF ASSOCIATED CLOUDS ACROSS
EASTERN WV HAVE BEEN ERODING DURING THE PAST FEW HOURS AND HAVE
NOW LEFT KBLF...ALTHOUGH STILL HANGING IN AT KLWB.
WEDGE DEVELOPMENT WILL RESULT IN WINDS COMING AROUND TO THE E-SE
THROUGH THE DAY SATURDAY AND LOW-LEVEL MOISTURE WILL RETURN IN
EARNEST FROM THE SOUTHEAST. LOW END VFR CIGS ARE EXPECTED FROM
KDAN-KLYH AND KROA BY MID-LATE MORNING...CREEPING NORTHWEST TOWARD
KBCB/KBLF/KLWB BY EARLY TO MID-AFTERNOON. CIGS COULD TREND TOWARD
HIGH END MVFR BY 00Z SUN.
VISIBILITY IS NOT EXPECTED TO BE MUCH OF CONCERN THROUGH THIS TAF
VALID PERIOD...ALTHOUGH SOME BR POSSIBLE AT KLWB AND PERHAPS EVEN
KBCB IN THE 08Z-13Z TIME FRAME AND -SHRA POSSIBLY REDUCING
VISIBILITY AT KDAN WITH LIGHT BR LATELY. CONFIDENCE IS LOW IN
EITHER OF THESE OCCURRING.
WINDS WILL VEER TO THE NORTHEAST OVERNIGHT...THEN EAST-SOUTHEAST
SATURDAY AS A WEDGE DEVELOPS AND HIGH PRESSURE MOVES OFF THE MID-
ATLANTIC COAST. SPEEDS MOSTLY 5-8KTS THROUGH THE PERIOD...BUT
SLIGHTLY HIGHER WITH LOW END GUSTS POSSIBLE KLYH-KDAN AFT 14Z SAT.
MEDIUM CONFIDENCE IN CIGS THROUGH THE TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN VSBYS THROUGH THE TAF VALID PERIOD.
MEDIUM CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID PERIOD.
EXTENDED DISCUSSION...
CIGS WILL CONTINUE TO LOWER AFT 00Z SUNDAY AND MOST AREAS WILL SEE
MVFR-IFR CIGS DEVELOP BY SUNDAY MORNING. THIS WILL CONTINUE
INTO EARLY SUNDAY AFTERNOON BEFORE POTENTIALLY SCATTERING OUT
FROM THE WEST AS THE WEDGE RETREATS NORTHEAST. BY SUNDAY
EVENING...AN UPPER TROUGH AND ASSOCIATED FRONTAL SYSTEM WILL BE
APPROACHING FROM THE WEST WITH MVFR-IFR CIGS/VSBYS LIKELY
OVERNIGHT IN RAIN SHOWERS FROM WEST TO EAST. BREEZY AND COOLER
CONDITIONS WILL FOLLOW FOR THE FIRST PART OF NEXT WEEK AS HIGH
PRESSURE BUILDS INTO THE REGION ALLOWING VFR CONDITIONS TO RETURN
BY MONDAY AFTERNOON. THE POSSIBLE DELAYED EXCEPTION WILL BE ACROSS
THE UPSLOPE AREAS OF WV WHERE LOW CLOUDS AND MVFR CIGS COULD
LINGER INTO MONDAY AFTERNOON.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...CF
NEAR TERM...PH/WP
SHORT TERM...CF
LONG TERM...CF
AVIATION...PH/RAB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 PM CDT WED MAR 23 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 300 PM CDT WED MAR 23 2016
HAVE BEEN MONITORING THE CURRENT FORECAST VERSUS OBSERVATIONS AND
THE LATEST MODEL DATA. STRONG FRONTOGENETIC BAND ANCHORED AT
600-700MB HAS NOW SHIFTED NORTH OF I-90 AS FORECAST WELL BY THE
RAP MODEL GUIDANCE. AS EVENING APPROACHES...A MORE SW-NE ORIENTED
BAND WILL BECOME ESTABLISHED FROM SOUTHEAST MN THROUGH CENTRAL
WI. THIS IS THE BAND CURRENTLY SEEN ON RADAR OVER MN...WHICH WILL
INTENSIFY AND DROP SOUTHEAST. GETTING SOME MIX OF SLEET AND
FREEZING DRIZZLE S-SW OF LA CROSSE PER OBSERVATIONS AND DUAL POL
CC PRODUCT.
VERY GOOD AND CONSISTENT DETERMINISTIC GUIDANCE COMING IN FOR THE
EVOLUTION OF THIS SYSTEM. OVERALL THE HEAVIEST LIQUID AMOUNTS LINE
UP WELL WITH OUR ONGOING FORECAST. THE LATEST WPC GUIDANCE PLACES
1.3 INCHES OF LIQUID IN THE FRONTOGENETIC BAND. SNOW RATIOS WILL
PROBABLY BE A BIG DETERMINISTIC FACTOR IN THE AMOUNT OF
SNOW...WITH 10-11 TO 1 PROBABLY ABOUT RIGHT.
SOUTH OF THE FRONTOGENETIC BAND...LOSS OF ICE ALOFT WILL CAUSE A
FREEZING DRIZZLE ENVIRONMENT. THIS MAY BE AROUND SOME HOURS UNTIL
THE CONVECTIVE SURGE THIS EVENING AND OVERNIGHT...WHERE DEEP ICE
WILL AGAIN ENTER THE AREA. THE WARM LAYER ALOFT IN THE SOUTH
REMAINS WARM ENOUGH FOR COMPLETE MELTING AS WELL AND COLD AIR IS
UNDERCUTTING THIS WARM LAYER LATER TONIGHT. WHILE THE ADVISORY
COVERS SOME OF THIS AREA...WE WILL BE WATCHING THE HIGHWAY 18
CORRIDOR FOR MORE ICING OVERNIGHT...AN ADVISORY MAY BE NEEDED.
TEMPERATURES REMAIN ABOVE FREEZING FOR A PERIOD TONIGHT...SO
ICING SHOULD BE MINIMIZED THERE. THE NEW FORECAST HAS ALSO SLOWED
THE SNOW EXIT ON THURSDAY MORNING...WITH ACCUMULATING SNOW STILL
IN WISCONSIN FOR THE COMMUTE HOURS.
THE ONLY OTHER CONCERN TO SHARE IS THE TREND IN THE LATEST HRRR
GUIDANCE WITH A FURTHER SOUTH /NERN IA-SWRN WI/ SOLUTION TO
CONVECTIVE ACTIVITY THIS EVENING...AND THE DIMINISHING
FRONTOGENETIC SW-NE BAND OVER SERN MN INTO CENTRAL WI. COMPARING
TO HOP WRF SOLUTIONS AND OTHER MESOMODELS...THINKING THE HRRR IS
AN OUTLIER SOLUTION AT THIS TIME.
BOTTOM LINE IS TRAVEL WILL GET PRETTY TREACHEROUS TONIGHT WITH
CONVECTIVE SNOW RATES OF 1-3 INCHES PER HOUR IN FRONTOGENETIC
BAND. INSTABILITY IS ALREADY SEEN IN THE RADAR IMAGERY WITH VERY
SHOWERY LOOKS TO ELEMENTS SOUTH OF THE MAIN SNOW BAND. ALSO SEEING
100 C-G LIGHTNING STRIKES ACROSS NEBRASKA...SO WE COULD BE IN FOR
A THUNDERSNOW TONIGHT. HAVE KEPT THE 10-14 INCH SNOW BAND FROM
SERN MN INTO CENTRAL WI. ICING AND SLEET WILL MIX IN TO THE SOUTH
WITH MAYBE A TENTH OF ICING.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 300 PM CDT WED MAR 23 2016
SIGNALS CONTINUE FOR SATURDAY WITH LIGHT PRECIPITATION EXPECTED
WITH SHORTWAVE ENERGY. HAVE CONTINUED PREVIOUS FORECAST WITHOUT
CHANGES...WITH RAIN SHOWERS LOOKING MORE LIKELY IN THE AFTERNOON
IN WISCONSIN.
MONITORING CONTINUES FOR THE SUNDAY-MONDAY TIME FRAME ON MORE
SIGNIFICANT ENERGY SHIFTING THROUGH THE BROAD LONG WAVE TROUGH
THROUGH THE CENTRAL U.S. BOTH THE 23.00Z AND 23.12Z ECMWF AND
23.12 CANADIAN SUGGEST THIS SHORTWAVE TROUGH ENERGY IS STRONGER
THAN THE GFS SYSTEM OF SOLUTIONS...WITH A SLIGHT NEGATIVE TILT AND
WELL FORMED DEFORMATION PRECIPITATION SHIELD WHICH LOOKS TO BE
SNOW ON THE NORTHWEST SIDE. THIS COULD AFFECT SOUTHWEST OR CENTRAL
WI DEPENDING ON THE TREND. THE PROGRESSIVE PREVIOUS TWO RUNS OF
THE GFS HAVE NO WEATHER FOR THIS TIME FRAME. HAVE CARRIED LOW
RANGE CHANCES FOR PRECIPITATION AT THIS TIME.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 1100 PM CDT WED MAR 23 2016
WINTER STORM IMPACTS KRST/KLSE INTO THU MORNING...WITH IFR/LIFR CIGS
AND VSBYS. EXPECT THE BULK OF THE ACCUMULATING SNOWS TO END BETWEEN
12-15Z THU...WITH GRADUAL IMPROVEMENT IN THE CIGS DURING THE
AFTERNOON/EVENING.
NEXT DEFORMATION REGION QUICKLY DEVELOPING NORTH OF THE SFC LOW LATE
THIS EVENING. SNOW FALLING IN THIS REGION...WITH OBS SHOWING SUB 1SM
VSBYS. EXPECT VSBYS FROM 1/4 TO 1SM FOR MOST OF THE OVERNIGHT.
HOURLY SNOWFALL RATES OF 1-2 INCHES POSSIBLE...WITH ACCUMS BY 12Z
THU FROM 6 TO 8 WET INCHES. SOME THUNDER TO THE SOUTH...AND CAN/T
RULE OUT A CRACK OF THUNDER AT KRST/KLSE...BUT NOT ENOUGH CONFIDENCE
TO ADD TO FORECAST.
WINDS WILL STAY RELATIVELY STRONG AND GUSTY THROUGH THE
OVERNIGHT...BUT LITTLE IF ANY BLOWING/DRIFTING DUE TO THE WET NATURE
OF THE SNOW.
&&
.HYDROLOGY...
ISSUED AT 300 PM CDT WED MAR 23 2016
DUE TO THE EXCESSIVE RAINFALL FROM LAST WEEK...AREA RIVERS
CONTINUE TO RUN HIGHER THAN NORMAL. FLOOD WARNINGS CONTINUE FOR
THE MISSISSIPPI RIVER AT BOTH GUTTENBERG AND MCGREGOR AND THE
WISCONSIN RIVER AT MUSCODA.
SNOW MELT FROM THIS SYSTEM MAY PROLONG ELEVATED LEVELS IN AREA
RIVERS. ONLY THOSE RIVERS NEAR FLOOD STAGE WOULD POSSIBLY RE-ENTER
FLOOD STAGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL NOON CDT THURSDAY
FOR WIZ041>044-053.
WINTER STORM WARNING UNTIL NOON CDT THURSDAY FOR WIZ017-029-
032>034.
WINTER WEATHER ADVISORY UNTIL NOON CDT
THURSDAY FOR WIZ054-055.
MN...WINTER STORM WARNING UNTIL NOON CDT THURSDAY
FOR MNZ094>096.
WINTER STORM WARNING UNTIL NOON CDT THURSDAY FOR MNZ079-086>088.
IA...WINTER STORM WARNING UNTIL NOON CDT THURSDAY
FOR IAZ008>010-018-019.
WINTER WEATHER ADVISORY UNTIL NOON CDT
THURSDAY FOR IAZ011.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...RIECK
HYDROLOGY...BAUMGARDT
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
143 AM EDT SAT MAR 26 2016
.AVIATION...
AREAS OF MVFR CEILINGS ALONG WITH A FEW SHOWERS AND POSSIBLY A
THUNDERSTORM WILL CONTINUE OVERNIGHT AT TPA...PIE...LAL AND SRQ.
FURTHER SOUTH TOWARD PGD...FMY AND RSW...PATCHY FOG WITH SOME
MVFR CEILINGS AND VISIBILITIES WILL BE POSSIBLE OVERNIGHT. THEN
DURING THE DAY SATURDAY WE COULD SEE SOME MORE MVFR/LOCAL IFR
CONDITIONS IN SCATTERED CONVECTION...BUT IT LOOKS LIKE THE THREAT
OF CONVECTION WILL MOVE INLAND AWAY FROM THE COASTAL SITES DURING
THE AFTERNOON HOURS.
&&
.PREV DISCUSSION... /ISSUED 842 PM EDT FRI MAR 25 2016/
UPDATE (REST OF THE OVERNIGHT)...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOW MUCH OF THE CONUS NOW
UNDER A VERY BROAD LONGWAVE TROUGH. THE FLORIDA PENINSULA RESIDES
WITHIN THE EASTERN BASE REGION OF THIS TROUGH...ALLOWING A SERIES
OF UPPER LEVEL IMPULSES TO QUICKLY MIGRATE ACROSS THE GULF OF
MEXICO AND OVER THE STATE. ONE SUCH IMPULSE BROUGHT QUITE A BIT OF
THUNDERSTORM ACTIVITY TO THE I-4 CORRIDOR OF THE STATE THIS PAST
AFTERNOON...BUT NOW APPEARS TO BE EXITING OFF THE FLORIDA EAST
COAST ALLOWING FOR A QUIETER PERIOD OF WEATHER FOR THE REMAINDER
OF THE EVENING ACROSS OUR FORECAST AREA. HOWEVER...LOOKING AT WV
AND COOLING CLOUD TOPS ACROSS THE EAST-CENTRAL GULF SUGGEST YET
ANOTHER WEAK IMPULSE IS DOWNSTREAM AND HEADED OUR WAY. NUMERICAL
WEATHER PREDICTION HAS HAD A HARD TIME GETTING A GOOD HANDLE ON
THESE WEAK IMPULSES OVER THE GULF...AND HAS NOT BEEN MUCH USE THE
PAST 24 HOURS...EVEN IN THE SHORT TERM. MOST GUIDANCE SOLUTIONS
SUGGEST BETTER RAIN CHANCES WILL BE OVER THE NATURE COAST LATER
TONIGHT...BUT WATCHING THE EXPANDING AREA OF COOLER CLOUD TOPS
TELL US THAT DECENT SYNOPTIC LIFT IS OCCURRING ON A TRAJECTORY
THAT WOULD BRING RAINFALL A BIT FURTHER SOUTH. ALL THIS IS
ASSUMING THE ACTIVITY HOLD TOGETHER ALL THE WAY TO THE COAST. WITH
A LOWER THAN NORMAL CONFIDENCE LEVEL AS TO JUST WHERE AND JUST
WHEN THE NEXT ROUND OF CONVECTION WILL FIND ITS WAY TO THE FLORIDA
PENINSULA...HAVE NOT GONE WITH ANY REALLY HIGH RAIN CHANCES FOR
THE OVERNIGHT...BUT RATHER HAVE SIDED WITH A LOWER AND MORE BROAD
CHANCE POP FOR THE AREA. AS SATELLITE AND RADAR TREND CONTINUE TO
DEVELOP AND CONFIDENCE INCREASES...THESE FORECASTS CAN BE UPDATED
WITH MORE DETAIL...AND HOPEFULLY GIVE A FEW HOURS NOTICE WITH ANY
SIGNIFICANT CHANCES. ALSO HOPEFULLY THE 00Z SUITE OF GUIDANCE WILL
SEE AN IMPROVEMENT IN THE INITIALIZATION OF FEATURES.
SO AS MENTIONED ABOVE...THE NEXT FEW HOURS LOOK GENERALLY
DRY...OTHER THAN A FEW LIGHT SPRINKLES HERE AND THERE. THEN AFTER
MIDNIGHT...RAIN CHANCES INCREASE...ESPECIALLY TOWARD THE COAST AND
FROM TAMPA BAY NORTHWARD AS THE NEXT IMPULSE APPROACHES FROM THE
EASTERN GULF OF MEXICO.
PREVIOUS DISCUSSION (SATURDAY)...
FOR SATURDAY...THINGS LOOK QUITE SIMILAR...WITH ANOTHER WEAK MID
LEVEL IMPULSE MOVING NORTHEASTWARD ALONG THE STALLED FRONT. THIS
CURRENTLY LOOKS TO FAVOR RAIN ALONG THE NATURE COAST AND INTO THE
NORTHERN FLORIDA PENINSULA...HOWEVER...MUCH LIKE TODAY...IF
CONVECTION DEVELOPS FURTHER SOUTH OVER THE WARM GULF WATERS...THIS
AREA COULD SHIFT SOUTHWARD. MORE SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY LOOKS TO OCCUR DURING THE AFTERNOON HOURS AS THE
SEA BREEZE DEVELOPS...WITH THE GREATER RAIN CHANCES OVER INTERIOR
PORTIONS OF THE PENINSULA.
TEMPERATURES WILL GENERALLY REMAIN AT OR ABOVE NORMAL...DEPENDING
LARGELY ON THE EXTENT OF CLOUD COVER AND ANY CONVECTIVE DEBRIS
ADRIFT DURING PEAK HEATING EACH DAY. OVERNIGHT LOWS LOOK TO REMAIN
SOLIDLY IN UPPER 60S TO LOWER 70S TERRITORY.
MARINE...
SOUTHERLY WINDS WILL CONTINUE TO THE SOUTH OF A STALLED FRONT
OVER THE FLORIDA PANHANDLE AND SOUTHERN GEORGIA. ANOTHER ROUND OR
TWO OF SHOWERS AND STORMS MOVING ALONG THIS FRONT WILL BE POSSIBLE
ACROSS THE WATERS INTO THE WEEKEND. THE FRONT LOOKS TO SHIFT
SOUTHWARD LATE MONDAY INTO TUESDAY...WITH A NORTHERLY WIND SHIFT
OVER THE NORTHER WATERS. HOWEVER...WINDS AND SEAS LOOK TO REMAIN
WELL BELOW HEADLINE CRITERIA OVER THE NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 82 72 80 72 / 30 30 30 40
FMY 87 71 85 71 / 30 30 30 20
GIF 85 71 84 71 / 60 40 60 40
SRQ 79 69 78 71 / 20 30 20 40
BKV 84 70 82 70 / 40 40 50 40
SPG 80 72 79 72 / 20 30 20 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
AVIATION...69/CLOSE
PREV DISCUSSION...14/MROCZKA
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
410 AM EDT SAT MAR 26 2016
.SYNOPSIS...
A WEAK COLD FRONT WILL STALL NEARBY TODAY...THEN LIFT NORTH AS A
WARM FRONT SUNDAY. A WEAK COLD FRONT WILL MOVE THROUGH THE AREA
MONDAY MORNING AND BE FOLLOWED BY A STRONGER REINFORCING COLD
FRONT MONDAY NIGHT. HIGH PRESSURE WILL BUILD IN FOR THE MIDDLE OF
NEXT WEEK BEFORE A STORM SYSTEM AFFECTS THE AREA LATE NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
THROUGH SUNRISE...A WEAK IMPULSE EMBEDDED IN THE SUBTROPICAL JET
WILL MOVE NORTHEAST OVER THE AREA OVER THE NEXT SEVERAL HOURS.
WEAK FORCING WITH THIS FEATURE COUPLED WITH THE WARM/MOIST AIRMASS
THAT IS IN PLACE AHEAD OF THE APPROACHING COLD FRONT WILL SUPPORT
SCATTERED SHOWERS AND POSSIBLY A FEW TSTMS THROUGH SUNRISE WITH
THE LATEST RAP/H3R SUPPORTING A SLIGHTLY GREATER COVERAGE AT THE
COAST.
TODAY...A COLD FRONT MOVING THROUGH THE CAROLINA PIEDMONT INTO
CENTRAL GEORGIA WILL MEANDER INTO THE INTERIOR PORTIONS OF
SOUTHEAST SOUTH CAROLINA AFTER DAYBREAK BEFORE BUCKLING BACK TO
THE NORTH ACROSS THE SOUTHERN MIDLANDS AND CSRA LATER TODAY. A
WARM AND MOIST AIRMASS WILL REMAIN IN PLACE ACROSS THE REGION
AHEAD OF THE FRONT WITH PWATS FORECAST TO SURGE TO 1.5-1.75
INCHES. A NUMBER OF UPSTREAM IMPULSES EMBEDDED WITHIN THE
SUBTROPICAL JET WILL TRAVERSE THE SOUTHEAST U.S. TODAY...THE
STRONGEST OF WHICH WILL PASS ACROSS SOUTHEAST GEORGIA EARLY THIS
AFTERNOON. UPPER FORCING WITH THIS FEATURE COUPLED WITH A WELL-
DEFINED 250 HPA DIFLUENCE SIGNATURE AND STRONG ISENTROPIC ASSENT
NOTED ALONG THE NOSE OF 35 KT LOW-LEVEL JET WILL SUPPORT A STEADY
UPTICK IN CONVECTION AFTER SUNRISE WHICH WILL GRADUALLY FILL IN
AND IMPACT MUCH OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA
THROUGH THE DAY.
THERE ARE SIGNALS THAT SOME SORT OF CONVECTIVE CLUSTER COULD MOVE
ACROSS NORTHERN FLORDIA AND FAR SOUTHEAST GEORGIA LATER THIS
MORNING. SHOULD THIS FEATURE DEVELOP...IT COULD DISRUPT THE
INFLOW OF MOISTURE INTO SOUTHERN SOUTH CAROLINA AND THUS LIMIT
THE COVERAGE OF SHOWERS AND TSTMS. THE POP FORECAST WILL REMAIN
FAIRLY CONSERVATIVE FOR THIS REASON...RANGING FROM 70 PERCENT FOR
MUCH OF SOUTHERN SOUTH CAROLINA TO 80 PERCENT ACROSS SOUTHEAST
GEORGIA. HIGHS WILL ONLY WARM INTO THE MID 70S FOR MOST AREAS
TODAY DUE TO EXTENSIVE CLOUD COVER AND DEVELOPING SHOWERS/TSTMS.
COULD SEE AN AREA OF ENHANCED INSTABILITY DEVELOP IN THE SAVANNAH-
DARIEN-LUDOWICI CORRIDOR WHERE MODIFIED RAP SOUNDINGS SHOW
SBCAPES NEARING 1200 J/KG WITH LIFTED INDICES -4 TO -6C. GIVEN THE
AMOUNT OF 0-6KM BULK SHEAR THAT IS PLACE AND THE PRESENCE OF A
MODEST LOW-LEVEL JET...AN ISOLATED STRONG TO PERHAPS SEVERE TSTM
CAN NOT BE RULED OUT IN THIS AREA.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
TONIGHT...THE RISK FOR ISOLATED TO SCATTERED SHOWERS WILL LINGER
THE NIGHT AS THE AREA REMAINS FULLY EMBEDDED WITHIN THE WARM
SECTOR AND A POWERFUL SUBTROPICAL JET REMAINS IN PLACE ALOFT. MORE
CONCENTRATED ACTIVITY WILL BEING TO IMPACT INTERIOR SOUTHEAST
GEORGIA CLOSER TO DAYBREAK SUNDAY AS YET ANOTHER SHORTWAVE
EMBEDDED WITHIN THE SUBTROPICAL JET APPROACHES. LOWS WILL RANGE
FROM THE LOWER TO MID 60S...WARMEST SOUTH OF THE I-16 CORRIDOR.
SUNDAY AND SUNDAY NIGHT... A BACKDOOR COLD FRONT WILL PUSH SOUTHWARD
INTO THE CAROLINAS EARLY SUNDAY MORNING AS HIGH PRESSURE BUILDS OVER
NEW ENGLAND. AS THE HIGH MOVES OFF OF THE NEW ENGLAND COAST DURING
THE DAY THE FRONT WILL TRANSITION INTO A WARM FRONT AND THEN LIFT
NORTHWARD INTO THE MID-ATLANTIC STATES. WARM AIR ADVECTION WILL
INCREASE THROUGH THE DAY. NAEFS SHOWS HIGHEST ATMOSPHERIC MOISTURE
CONTENT THROUGH THIS PERIOD WITH P-WATS 2 TO 3 STANDARD DEVIATIONS
ABOVE NORMAL STREAMING INTO THE AREA ON THE BACK OF DEEP LAYER
SOUTHWESTERLY FLOW.
A SHORTWAVE ALOFT MOVING ACROSS THE SOUTHEAST WILL PASS NEAR OR OVER
THE AREA SUNDAY AFTERNOON OR EVENING. AS THIS BAROCLINIC ZONE
APPROACHES THE AREA MAINLY DYNAMICALLY DRIVEN PRECIP WILL ENSUE.
GIVEN THE HIGH MOISTURE VALUES AND PVA ALOFT AT LEAST NUISANCE
FLOODING IS POSSIBLE...WITH WIDESPREAD FLOODING NOT EXPECTED.
OVERALL LACK OF INSTABILITY WILL GREATLY LIMIT THE SEVERE THREAT.
POPS CONTINUE SUNDAY NIGHT AS THE SHORTWAVE CROSSES THE AREA.
THICK CLOUD COVER WILL PROVIDE AMPLE INSULATION AND TEMPS WILL ONLY
FALL ABOUT 10F FROM THE DAYTIME HIGHS. SOME STRATUS BUILD DOWN IS
POSSIBLE BETWEEN SHOWERS GIVEN THE AMPLE MOISTURE IN THE LOW
LEVELS...BUT CONFIDENCE IN VISIBILITY REDUCTIONS IS STILL TOO LOW TO
INCLUDE IN THE OFFICIAL FORECAST AT THIS POINT.
MONDAY...AN INITIAL WEAK COLD FRONT WILL CROSS THE AREA AROUND
SUNRISE MONDAY...BRINGING WESTERLY FLOW DURING THE DAY. THIS WILL
LEAD TO THE WARMEST TEMPS OF THE PERIOD WITH HIGHS NEAR 80 FOR MOST.
KEPT SLIGHT CHANCE POPS IN THE FORECAST THROUGH THE DAY AS MOISTURE
CONTENT REMAINS SOMEWHAT ELEVATED IN THE LOW LEVELS.
ZONAL FLOW ALOFT OR POSSIBLY WEAK RIDGING WILL FILL IN AND THE UPPER
LEVELS WILL DRY OUT KEEPING ANY SHOWER ACTIVITY ISOLATED IN NATURE
AND PRECLUDING ANY SEVERE THREAT. DRIER CONDITIONS ARE EXPECTED
DURING THE EVENING AND OVERNIGHT AS SURFACE HIGH PRESSURE BUILDS
ACROSS THE EASTERN HALF OF THE U.S. LOW TEMPERATURES WILL BE
SLIGHTLY ABOVE NORMAL.
TUESDAY...SURFACE HIGH PRESSURE CENTERED OVER THE GREAT LAKES WILL
STRETCH DOWN INTO THE CAROLINAS WHILE A RIDGE WILL BE MOVING OVER
THE MISSISSIPPI VALLEY. NORTHEAST WINDS AT THE SURFACE COMBINED WITH
NORTHWEST WINDS ALOFT WILL USHER IN COOLER TEMPERATURES TO OUR
REGION. DESPITE PLENTY OF SUN...HIGH TEMPERATURES MAY BE SLIGHTLY
BELOW NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
DRY HIGH PRESSURE WILL BUILD INTO THE AREA TUESDAY NIGHT AND
WEDNESDAY. TEMPERATURES WILL BE NEAR NORMAL. A WARMING TREND IS
EXPECTED THURSDAY AS THE HIGH MOVES OFFSHORE. A LOW PRESSURE SYSTEM
WILL APPROACH THE SOUTHEASTERN U.S. BY THURSDAY...BRINGING OUR AREA
THE THREAT OF RAIN INTO FRIDAY.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
KCHS...WATCHING FOR POSSIBLE FOG/STRATUS DEVELOPMENT OVER THE NEXT
FEW HOURS A COLD FRONT APPROACHES. WINDS ATOP THE BOUNDARY LAYER
ARE FORECAST TO INCREASE AFTER 09Z...WHICH SHOULD FAVOR STRATUS
OVER FOG. WILL CARRY PREVAILING MVFR CIGS BY 09Z WITH TEMPO GROUPS
FOR IFR FROM 10-12 BUT KEEP CIGS ABOVE ALTERNATE MINIMUMS. THERE
ARE SIGNALS AN AREA OF LIGHT SHOWERS COULD PASS THROUGH JUST ABOUT
THIS TIME...WHICH MAY TEMPER CONDITIONS A BIT. WILL MONITOR TRENDS
AND ADJUST AS NEEDED. OTHERWISE...VFR CIGS ARE EXPECTED TO PREVAIL
FROM MID-MORNING THROUGH LATE AFTERNOON BEFORE AREAS OF SHOWERS
IMPACT THE TERMINALS. THERE IS A RISK FOR TSTMS...BUT MARGINAL
INSTABILITY SUGGESTS RISK IS TOO LOW TO JUSTIFY A MENTION. WINDOW
OF GREATEST IMPACT LOOKS TO BE ROUGHLY 19-23Z.
KSAV...RISK FOR FOG/STRATUS LOOKS TO REMAIN NORTH OF THE TERMINAL
THROUGH SUNRISE. AN AREA OF SHOWERS/TSTMS MOVING ACROSS NORTHEAST
GULF COULD PASS NEAR THE TERMINAL ROUGHLY 09-12Z. WILL MONITOR
TRENDS...BUT THE BULK OF THIS LOOKS TO PASS TO THE SOUTH. THERE
WILL BE INCREASED RISK FOR SHOWERS/TSTMS LATER THIS MORNING WHICH
WILL LINGER THROUGH MID AFTERNOON BEFORE SHIFTING NORTH. WILL HOLD
CONDITIONS AT MVFR FOR NOW...ALTHOUGH IFR CONDITIONS MAY BE
NEEDED.
EXTENDED AVIATION OUTLOOK...PERIODS OF FLIGHT RESTRICTIONS ARE
EXPECTED SUNDAY THROUGH MONDAY MORNING DUE TO A FRONT STALLING OVER
OR NEAR THE AREA.
&&
.MARINE...
TODAY...LIGHT WINDS THIS MORNING WILL BECOME SOUTH AND INCREASE TO
NEAR 10 KT LATER THIS MORNING. SEAS WILL AVERAGE 2-4 FT.
TONIGHT...A LIGHT...SOUTHERLY WIND REGIME WILL HOLD THROUGH THE
NIGHT AS A STATIONARY FRONT REMAINS TO THE THE WEST. SEAS WILL
AVERAGE 2-4 FT.
SUNDAY THROUGH WEDNESDAY...SUNDAY A WARM FRONT WILL LIFT NORTHWARD...
CAUSING INCREASED SOUTHWESTERLY WINDS. CONDITIONS WILL IMPROVE
MONDAY AS A COLD FRONT APPROACHES AND THEN MOVES THROUGH THE
REGION. HIGH PRESSURE WILL THEN PASS TO OUR NORTH THROUGH THE
MIDDLE OF NEXT WEEK.
RIP CURRENTS...LATEST OBSERVATIONS AND OUTPUT FROM NWPS INDICATES
1-2 FT SWELLS OF 8-9 SECONDS WILL IMPACT THE BEACHES TODAY.
DESPITE THIS AND SOME LINGERING ASTRONOMICAL INFLUENCES... FAIRLY
LIGHT WINDS OF 10 KT OR LESS WILL LIMIT THE OVERALL RIP CURRENT
RISK. A LOW RISK WILL BE INDICATED FOR ALL BEACHES THROUGH SUNSET.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/MS
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
403 AM EDT SAT MAR 26 2016
.SYNOPSIS...
A COLD FRONT WILL STALL ACROSS THE AREA TODAY THEN RETREAT
NORTHWARD AS A WARM FRONT SUNDAY. THIS WILL RESULT IN SCATTERED TO
NUMEROUS SHOWERS ACROSS THE REGION TODAY AND SUNDAY. A FEW
THUNDERSTORMS ARE POSSIBLE. ANOTHER COLD FRONT WILL MOVE ACROSS
THE REGION MONDAY. TEMPERATURES AT OR SLIGHTLY BELOW NORMAL
THROUGH THE WEEKEND. HIGH PRESSURE WILL OVERSPREAD THE REGION
TUESDAY AND WEDNESDAY. ANOTHER CHANCE FOR RAIN WILL REENTER THE
REGION BY THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
PATCHY DENSE FOG DEVELOPING ACROSS THE NORTH MIDLANDS THIS
MORNING AHEAD OF COLD FRONT SLIPPING INTO THE AREA FROM THE
NORTH. THE FRONT IS FORECAST TO STALL OVER MIDLANDS TODAY.
GOOD AGREEMENT AMONG THE HIGH RESOLUTION AND NEAR TERM MODELS IN
SHOWING AN INCREASE IN SHOWERS THIS MORNING AS A WEAK SHORTWAVE
LIFTS NORTHEASTWARD INTO THE AREA AND INTERACTS WITH THE FRONTAL
BOUNDARY. CONSENSUS GUIDANCE POPS INDICATED LIKELY TO CATEGORICAL
POPS. A WEAK SHALLOW WEDGE IS FORECAST TO DEVELOP ACROSS THE
NORTHERN MIDLANDS WITH NORTHEAST LOW LEVEL FLOW. DEEPER MOISTURE
AND GREATER INSTABILITY FORECAST ACROSS THE SOUTHERN MIDLANDS AND
CSRA WILL LEAD TO THE CHANCE FOR A FEW THUNDERSTORMS.
THE COMBINATION OF CLOUDS...THE SHALLOW WEDGE AND SHOWERS WILL
SHOULD HOLD TEMPERATURES IN THE 60S ACROSS THE NORTH MIDLANDS WITH
WARMER READINGS IN THE LOWER 70S ACROSS THE SOUTHERN MIDLANDS AND
CSRA. COULD SEE SHOWERS DECREASE TONIGHT AS INSTABILITY DECREASES
AND SHORT WAVE ENERGY LIFTS OUT OF THE FORECAST AREA. KEPT
OVERNIGHT LOWS NEAR GUIDANCE CONSENSUS...IN THE MID 50S NORTH TO
LOWER 60S SOUTH.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
THE STALLED FRONTAL BOUNDARY IS FORECAST TO LIFT NORTH OF THE
MIDLANDS AS A WARM FRONT SUNDAY. INCREASING MOISTURE AND
INSTABILITY SOUTH OF THE BOUNDARY WILL HOLD THE THREAT OF
SHOWERS AND THUNDERSTORMS ACROSS THE AREA SUNDAY. GUIDANCE
CONSENSUS CONTINUE TO INDICATE CATEGORICAL POPS. QPF AROUND 1 TO
2 INCHES POSSIBLE MAINLY IN THE SOUTHEAST MIDLANDS/CSRA.
GUIDANCE IN GOOD AGREEMENT WITH HIGHS IN THE UPPER 60S TO MID 70S
ON SUNDAY.
BROAD UPPER LEVEL TROUGH MOVING EAST ACROSS THE TENNESSEE AND
OHIO VALLEY SUNDAY NIGHT WILL DRIVE ANOTHER COLD FRONT THROUGH THE
REGION MONDAY AFTERNOON. EXPECT MOST SHOWERS TO MOVE EAST OF THE
AREA EARLY MONDAY SO DECREASING POPS DURING THE DAY WITH CLEARING
BY AFTERNOON AS MOISTURE BECOMES SHALLOW AND DEVELOPMENT OF MID
LEVEL CAP. GUIDANCE GIVES HIGH TEMPERATURES AROUND 80S WITH DRYING
AND DOWNSLOPE FLOW DEVELOPING.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER LEVEL RIDGE IS FORECAST TO BUILD FROM THE CENTRAL CONUS TO
THE EAST COAST TUESDAY THROUGH WEDNESDAY...MOVING OFF THE OFF THE
COAST THURSDAY. THIS SHOULD HELP TO BRING A PERIOD OF DRY WEATHER
BACK TO THE AREA THROUGH MID-WEEK. PRECIP REENTERS THE FORECAST
ONCE AGAIN THURSDAY INTO FRIDAY AHEAD OF THE NEXT SYSTEM. GUIDANCE
BLEND POPS INCREASING SO RAISED POPS LATE WEEK. TEMPERATURES ARE
EXPECTED TO BE NEAR NORMAL.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
MVFR TO IFR CONDITIONS EXPECTED TO DOMINATE THE PERIOD.
SURFACE OBS INDICATE AREAS OF LOW CLOUDS CONTINUE TO DEVELOP
ACROSS THE MIDLANDS AND CSRA...WITH MANY SITES BEGINNING TO DROP
BELOW 1 KFT. EXPECT THE LOW CLOUDS TO CONTINUE DEVELOPING OVER
THE NEXT COUPLE OF HOURS. MOST SITES IFR ALREADY...WITH OGB THE
EXCEPTION. OGB WILL DROP INTO MVFR AS LOWER CLOUDS DEVELOP ACROSS
THE SOUTHEASTERN MIDLANDS.
BY SUNRISE A PUSH OF GULF MOISTURE WILL BE MOVING NORTHWARD ALONG
THE FRONT AND BRING SHOWERS TO THE AREA. HRRR SHOWS THAT THE HIGHEST
CHANCE OF SHOWERS AT AGS/DNL/OGB SHOULD OCCUR FROM LATE MORNING
THROUGH THE END OF THE PERIOD...WITH SIMILAR CONDITIONS BEGINNING
AT CAE/CUB AN HOUR OR SO LATER. THUNDERSTORMS WILL BE POSSIBLE
FROM 16Z ONWARD...HOWEVER THE POTENTIAL FOR CONVECTION REMAINS TOO
LOW TO INCLUDE ATTM. WINDS THROUGH THE PERIOD WILL BE SOUTHWESTERLY
THROUGH THE EARLY MORNING HOURS...THEN BACK TO EASTERLY FOR THE
REMAINDER OF THE PERIOD WITH SPEEDS OF 6 KNOTS OR LESS.
EXTENDED AVIATION OUTLOOK...INCREASING CONFIDENCE IN IFR
CONDITIONS PRE-DAWN SUNDAY THROUGH MONDAY MORNING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
130 AM EDT SAT MAR 26 2016
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO THE AREA AND STALL JUST SOUTH OF THE
REGION THROUGH SATURDAY. THE FRONT WILL LIKELY MOVE NORTH AS A
WARM FRONT SUNDAY. THIS WILL RESULT IN SCATTERED TO NUMEROUS
SHOWERS ACROSS THE REGION ESPECIALLY SUNDAY. A FEW THUNDERSTORMS
ARE POSSIBLE. ANOTHER COLD FRONT WILL MOVE ACROSS THE REGION
MONDAY.TEMPERATURES AT OR SLIGHTLY BELOW NORMAL THROUGH THE
WEEKEND. HIGH PRESSURE WILL OVERSPREAD THE REGION TUESDAY AND
WEDNESDAY. ANOTHER CHANCE FOR RAIN WILL REENTER THE REGION BY THE
END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
COLD FRONT WILL SLOWLY PUSH INTO THE MIDLANDS OVERNIGHT. REGIONAL
RADAR IMAGERY SHOWS MORE SUBSTANTIAL RAINFALL CONTINUES TO FALL
SOUTHEAST OF OUR FORECAST AREA ACROSS SOUTHERN GEORGIA ASSOCIATED
WITH SHORTWAVE ENERGY LIFTING OUT OF THE NORTHEASTERN GULF OF
MEXICO. HAVE LOWERED POPS ACROSS THE AREA THROUGH THE REMAINDER OF
THE OVERNIGHT HOURS WITH EXPECTATION OF LITTLE IF ANY PRECIPITATION
TO FALL.
GENERALLY GOOD AGREEMENT AMONG THE HIGH RESOLUTION AND NEAR TERM
MODELS IN SHOWING SOME INCREASE IN RAINFALL POTENTIAL DURING THE
PREDAWN HOURS AS A WEAK SHORTWAVE LIFTS NORTHEASTWARD INTO THE
AREA AND INTERACTS WITH THE STALLED FRONTAL BOUNDARY. TEMPERATURES
WILL COOL DOWN A BIT ON THE NORTH AND WEST SIDE OF THE FRONT
OVERNIGHT ACROSS THE NORTHERN AND WESTERN MIDLANDS AND UPPER CSRA
WHILE TO THE SOUTH OF THE FRONT TEMPERATURES WILL REMAIN MILD.
ADJUSTED CURRENT AND NEAR TERM TEMPS TO ACCOUNT FOR SLOWER ARRIVAL
OF FRONT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
THE COLD FRONT WILL BE STALLING OUT NEAR THE AREA. THE MODEL
CONSENSUS APPEARS TO BE ACROSS THE SOUTHEAST MIDLANDS. THE NAM
MODEL HAS THE FRONT FURTHER NORTH AND APPEARS TO BE AN OUTLIER.
DEEPER MOISTURE SOUTH OF THE FRONT AND MODELS SUGGEST HIGHEST QPF
IN THE COASTAL PLAIN OR SOUTHEAST MIDLANDS. A WEAK SHALLOW WEDGE
MAY DEVELOP ACROSS THE NORTHERN MIDLANDS SATURDAY AND WITH
NORTHEAST LOW LEVEL FLOW WILL LOWER TEMPERATURES AND BLEND IN
LOCAL WEDGE GUIDANCE. SO LOW 60S NORTH TO LOW 70S SOUTH OF
FRONT. TEMPERATURE FORECAST CONFIDENCE MODERATELY LOW. DEEPER
MOISTURE IN THE SOUTHEAST ALONG WITH STRONGER LIFT/INSTABILITY
ASSOCIATED WITH WEAK MID LEVEL SHORT WAVES. CONVERGENCE MAY BE
STRONGER THERE AS WELL WITH FRONT IN THE REGION. SO HIGHEST POPS
SATURDAY IN THE SOUTHEAST MIDLANDS. AIR MASS APPEARS A LITTLE
DRIER NORTHWEST OF CAE TO PIEDMONT...SO LOW CHANCE POPS IN THOSE
REGIONS. FRONT MOVING NORTH OF THE REGION SUNDAY AND INCREASING
MOISTURE/INSTABILITY ACROSS THE REGION. GUIDANCE CONSENSUS POPS
INCREASING TO NEAR CATEGORICAL DURING THE DAY SUNDAY SO RAISED
POPS. SCATTERED THUNDERSTORMS ESPECIALLY IN THE AFTERNOON WITH
WEAK TO MODERATE INSTABILITY. QPF AROUND 1 TO 2 INCHES POSSIBLE
MAINLY IN THE SOUTHEAST MIDLANDS/CSRA.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
BROAD UPPER LEVEL TROUGH MOVING EAST ACROSS THE TENNESSEE AND OHIO
VALLEY SUNDAY NIGHT WILL DRIVE ANOTHER COLD FRONT THROUGH THE
REGION MONDAY AFTERNOON. EXPECT MOST SHOWERS TO MOVE EAST OF THE
AREA EARLY MONDAY SO DECREASING POPS DURING THE DAY WITH CLEARING
BY AFTERNOON AS MOISTURE BECOMES SHALLOW AND DEVELOPMENT OF MID
LEVEL CAP.
UPPER LEVEL RIDGE IS FORECAST TO BUILD FROM THE CENTRAL CONUS TO THE
EAST COAST TUESDAY THROUGH WEDNESDAY...MOVING OFF THE OFF THE COAST
THURSDAY. THIS SHOULD HELP TO BRING A PERIOD OF DRY WEATHER BACK
TO THE AREA THROUGH MID-WEEK. PRECIP REENTERS THE FORECAST ONCE
AGAIN THURSDAY INTO FRIDAY AHEAD OF THE NEXT SYSTEM. GUIDANCE
BLEND POPS INCREASING SO RAISED POPS LATE WEEK. TEMPERATURES ARE
EXPECTED TO BE NEAR NORMAL.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
MVFR TO IFR CONDITIONS EXPECTED TO DOMINATE THE PERIOD.
SURFACE OBS INDICATE AREAS OF LOW CLOUDS CONTINUE TO DEVELOP
ACROSS THE MIDLANDS AND CSRA...WITH MANY SITES BEGINNING TO DROP
BELOW 1 KFT. EXPECT THE LOW CLOUDS TO CONTINUE DEVELOPING OVER
THE NEXT COUPLE OF HOURS. MOST SITES IFR ALREADY...WITH OGB THE
EXPECTION. OGB WILL DROP INTO MVFR AS LOWER CLOUDS DEVELOP ACROSS
THE SOUTHEASTERN MIDLANDS.
BY SUNRISE A PUSH OF GULF MOISTURE WILL BE MOVING NORTHWARD ALONG
THE FRONT AND BRING SHOWERS TO THE AREA. HRRR SHOWS THAT THE HIGHEST
CHANCE OF SHOWERS AT AGS/DNL/OGB SHOULD OCCUR FROM LATE MORNING
THROUGH THE END OF THE PERIOD...WITH SIMILAR CONDITIONS BEGINNING
AT CAE/CUB AN HOUR OR SO LATER. THUNDERSTORMS WILL BE POSSIBLE
FROM 16Z ONWARD...HOWEVER THE POTENTIAL FOR CONVECTION REMAINS TOO
LOW TO INCLUDE ATTM. WINDS THROUGH THE PERIOD WILL BE SOUTHWESTERLY
THROUGH THE EARLY MORNING HOURS...THEN BACK TO EASTERLY FOR THE
REMAINDER OF THE PERIOD WITH SPEEDS OF 6 KNOTS OR LESS.
EXTENDED AVIATION OUTLOOK...INCREASING CONFIDENCE IN IFR
CONDITIONS PRE-DAWN SUNDAY THROUGH MONDAY MORNING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
308 AM CDT SAT MAR 26 2016
.SHORT TERM...
303 AM CDT
THROUGH TONIGHT...
MAIN FORECAST CONCERNS/CHALLENGES WILL BE WITH CLOUD TRENDS
TODAY...AND THEN WITH PRECIP CHANCES LATE TONIGHT INTO SUNDAY.
RELATIVELY QUIET MORNING ACROSS THE AREA...AS HIGH SURFACE HIGH
STILL SPANNING MUCH OF THE REGION. GRADIENT ON WEST SIDE OF RIDGE
AXIS ALLOWING FOR A SOUTHEAST WIND THIS MORNING...ALTHOUGH LESS
THAN 10KT. THIS SURFACE PATTERN AND WIND DIRECTION WILL HELP WINDS
TO REALLY TURN OFF THE LAKE AS SOON AS LATE MORNING/MIDDAY...WHICH
WILL BE KEY WITH HIGH TEMPS FOR AREAS NEAR THE LAKE. WHILE TEMPS
RISE INTO THE MID TO UPPER 50S TODAY...AREAS NEAR THE LAKE WILL
LIKELY STAY IN THE LOW 40S. MADE LITTLE CHANGES TO HIGH TEMPS
TODAY CAPPING HIGHS IN THE UPPER 50S FOR AREAS OVER THE SOUTHERN
CWA. HOWEVER...DO THINK A FEW 60S WILL BE POSSIBLE. CLOUD COVER
WILL LIKELY IMPACT HIGHS AND DID MAKE SOME CHANGES WITH TRENDS
FROM THIS MORNING INTO THE AFTERNOON. ALTHOUGH THESE CLOUDS WILL
CONSIST OF PRIMARILY HIGH CLOUDS...THERE IS SOME POTENTIAL FOR
UPSTREAM MORE DENSE CLOUD COVER TO MOVE OVERHEAD TODAY. GIVEN THAT
LATEST IR IMAGERY IS SHOWING ONLY POCKETS OF MORE DENSE
CLOUDS AT THIS TIME...DID BACK OFF ON CLOUD COVER THIS MORNING.
PARTLY CLOUDY SKIES THIS MORNING SHOULD BECOME MORE PARTLY SUNNY
TO CLOUDY THIS AFTERNOON...ESPECIALLY FOR AREAS IN NORTHERN
ILLINOIS.
THIS INCREASE IN CLOUD COVER TODAY INTO TONIGHT IS DUE TO
UPSTREAM MID LEVEL ENERGY CURRENTLY MOVING THROUGH THE CENTRAL
PLAINS. THIS WAVE AND ATTENDANT SURFACE TROUGH WILL CONTINUE
EAST/NORTHEAST LATER TODAY INTO TONIGHT WITH DECENT MODEL
AGREEMENT ON PLACEMENT OF THESE FEATURES. THIS WILL INCLUDE
ASSOCIATED PRECIP...WHICH IS APPEARING TO STAY TO THE WEST AND
NORTHWEST OF THE CWA TODAY INTO THIS EVENING. AS THIS WAVE AND
SURFACE TROUGH CONTINUE EAST/NORTHEAST LATER TONIGHT IT DOES LOOK
LIKE AT LEAST SOME ISOLATED RAIN COULD BE POSSIBLE FOR AREAS
ACROSS NORTH CENTRAL ILLINOIS. HOWEVER...FORCING WILL LIKELY BE
STRONGER TO THE NORTH...AND SO ONLY HAVE SLIGHT CHANCE POPS.
RODRIGUEZ
&&
.LONG TERM...
303 AM CDT
SUNDAY THROUGH SATURDAY...
BETTER AGREEMENT THIS MORNING WITH ADDITIONAL UPSTREAM ENERGY
LIFTING THROUGH THE CENTRAL PLAINS TONIGHT INTO SUNDAY. SHOULD SEE
ASSOCIATED RAIN LIFT NORTHEAST INTO THE CWA SUNDAY MORNING...WITH
THE FOCUS INITIALLY SITUATED OVER NORTHERN ILLINOIS AND WITH
COVERAGE INCREASING BY THE MID MORNING TIME FRAME. DID MAKE LARGER
CHANGES WITH POPS WITH THIS BETTER AGREEMENT AND HAVE LIKELY POPS
SPREADING INTO NORTHERN ILLINOIS DURING THIS TIME. SOME SLIGHT
MODEL SPREAD GOING INTO SUNDAY AFTERNOON AND EVENING...WHILE THIS
TROUGH LIFTS THROUGH THE REGION AND SURFACE LOW DEEPENS. PRECIP
WILL STILL BE LIKELY OVER MUCH OF THE CWA SUNDAY AFTERNOON...BUT
THIS VARIABILITY WILL ADD TO SOME LOWER CONFIDENCE WITH HOW LONG
NORTHERN ILLINOIS STAYS IN THE MORE WIDESPREAD RAIN. WITH HIGHER
CONFIDENCE FOR THE SOUTHERN HALF OF THE CWA...INCREASED LIKELY
POPS IN THIS AREA BUT IF TRENDS WERE TO CONTINUE COULD SEE THE
NEED TO INCREASE POPS FURTHER NORTH. WITH WEAKER MOIST ADVECTION
OCCURRING OUT AHEAD OF THIS SYSTEM DO THINK HIGHER MOISTURE AND
ANY INSTABILITY WILL STAY JUST TO THE SOUTH OF THE CWA. HAVE
EXCLUDED ANY MENTION OF THUNDER...BUT WILL NEED TO CONTINUE
MONITORING FOR THIS POTENTIAL FOR THE FAR SOUTHERN CWA SUNDAY
AFTERNOON. SYSTEM WILL EXIT SUNDAY NIGHT WITH RAIN CHANCES HIGHEST
OVER NORTHWEST INDIANA IN THE EVENING...AND THEN WITH DRY
CONDITIONS LIKELY AFTER MIDNIGHT. DRY CONDITIONS STILL EXPECTED TO
START THE WORK WEEK WITH A WARMING TREND LIKELY INTO MIDWEEK...BUT
WITH A CHANCES FOR SHOWERS AND THUNDERSTORMS RETURNING BY
WEDNESDAY.
RODRIGUEZ
&&
.AVIATION...
FOR THE 06Z TAFS...
HIGH PRESSURE CENTERED OVER LAKE ONTARIO AND THE ST. LAWRENCE
VALLEY WILL MOVE NORTHEASTWARD TODAY WHILE LOW PRESSURE MOVES FROM
THE SOUTHERN HIGH PLAINS INTO IOWA BY THIS EVENING. LIGHT
SOUTHEAST WINDS ARE IN PLACE ACROSS THE TERMINALS AND WILL BE
SHIFTING A BIT MORE SOUTHERLY OVERNIGHT. THE FLOW WILL BE WEAK
ENOUGH THROUGH THE DAY TO ALLOW LAKE INFLUENCES TO TAKE OVER
TURNING WINDS EASTERLY MID/LATE AFTERNOON AND PROBABLY EAST-
NORTHEASTERLY AT TIMES AT ORD/MDW AND EVENTUALLY DPA. GYY IS A
BIT MORE OF A WILDCARD AND MAY STAY EAST TO SOUTHEAST THOUGH A
SHIFT TO NORTHEAST MAY BE SLIGHTLY FAVORED. VFR WILL PREVAIL WITH
VARIABLE MID AND HIGH CLOUD COVERAGE. WINDS WILL WORK THEIR WAY
BACK TO SOUTHEAST MID TO LATE EVENING THEN TURN SOUTH SUNDAY
MORNING AS SURFACE LOW PRESSURE DRIFTS INTO SOUTHWESTERN
WISCONSIN. ANY CHANCES FOR SHOWERS LOOK TO HOLD OFF UNTIL AT LEAST
SUNDAY MORNING WHEN A SHARPER UPPER TROUGH APPROACHES FROM THE
SOUTHWEST.
MDB
&&
.MARINE...
250 AM CDT
HIGH PRESSURE OVER THE ST. LAWRENCE VALLEY WILL DRIFT EAST TO THE
CANADIAN MARITIMES INTO SUNDAY MORNING. LOW PRESSURE WILL DEVELOP
FROM THE SOUTHERN PLAINS TO IOWA BY THIS EVENING THEN MEANDER
EASTWARD ACROSS LAKE MICHIGAN SUNDAY BEFORE DEEPENING AS IT MOVES
NORTHEAST ACROSS THE LOWER LAKES INTO MONDAY. FAIRLY LIGHT WINDS
TODAY WILL BE SOMEWHAT VARIABLE IN DIRECTION BETWEEN SOUTH AND
EAST BEFORE A STEADIER SOUTH TO SOUTHEAST BREEZE DEVELOPS EARLY
SUNDAY. WINDS WILL SHIFT TO THE WEST THEN NORTHWEST LATER SUNDAY
AFTERNOON THEN NORTHERLY SUNDAY NIGHT. WIND SPEEDS WILL INCREASE
AS WELL. WILL NEED TO KEEP AN EYE ON WHERE EXACTLY THE LOW ENDS UP
TRACKING AS WELL AS WHERE IT STARTS TO DEEPEN AS THIS MAY CAUSE
ISSUES WITH WIND DIRECTION/SPEED DETAILS FOR SUNDAY. AT THIS POINT
EXPECT THE LOW TO TRACK ACROSS SOUTHERN LAKE MICHIGAN OR EVEN JUST
SOUTH OF THE LAKE THEN DEEPEN FURTHER TO THE EAST. THIS WOULD KEEP
WIND SPEEDS CLOSER TO 20 KTS SUNDAY EVENING BEHIND THE LOW BUT A
QUICKER DEEPENING WOULD RESULT IN SOMEWHAT HIGHER SPEEDS.
HIGH PRESSURE QUICKLY RETURNS MONDAY BRINGING DECREASING WIND
SPEEDS AND A MORE VARIABLE DIRECTION. THE HIGH WILL SHIFT EAST
WEDNESDAY SETTING UP A STEADY SOUTHERLY WIND. ANOTHER LOW IS
EXPECTED TO MOVE NORTHEAST FROM THE SOUTHERN PLAINS TO THE WESTERN
LAKES INTO THURSDAY WITH DISAGREEMENT ABOUT HOW STRONG IT WILL BE
AND WHERE IT TRACKS. REGARDLESS...FAIRLY STRONG SOUTHERLY WINDS
SHOULD RESULT WITH THE STABLE MARINE LAYER KEEPING GUST SPEEDS TO
A MINIMUM CLOSE TO THE LAKE SURFACE. WEDNESDAY/THURSDAY WILL BE
THE PERIOD TO KEEP AN EYE ON HOWEVER AS THIS SYSTEM WILL HAVE THE
POTENTIAL TO BE ON THE STRONG SIDE AND GALES ARE NOT OUT OF THE
QUESTION.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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[top]
Area Forecast Discussion
National Weather Service Lincoln IL
256 AM CDT SAT MAR 26 2016
.SHORT TERM...(Today)
ISSUED AT 256 AM CDT Sat Mar 26 2016
Quiet weather is expected across central and southeast Illinois
today. High pressure will continue to pull away from the area, while
a slow moving storm system approaches from the plains. Southerly low-
level flow between these two features will push temperatures warmer
than they were yesterday, with most areas topping out in the lower
60s. The local airmass will remain too dry to support any rain today
from the approaching system, but periods of filtered sunshine can be
expected.
&&
.LONG TERM...(Tonight through Friday)
ISSUED AT 256 AM CDT Sat Mar 26 2016
Upper level feature of interest for the weekend is currently
centered over northern Utah, per water vapor satellite imagery. This
will stretch out into a shortwave and track southeast into the
Texas/Oklahoma panhandles by early Sunday morning, before moving
through Illinois Sunday evening. Have backed off some on Saturday
night PoP`s, limiting the slight chances to areas along and west of
the Illinois River after midnight with the drier air in place
initially. Timing on Sunday is a bit more of a challenge, though.
The NAM is on the slower side and keeps a large part of the area dry
through midday, while the GFS and ECMWF are a bit faster. The high-
resolution ARW/NMM are fastest and have almost the entire CWA dry by
mid afternoon. Each is indicating only about a 4-6 hour period with
the highest rain chances, but high enough that likely PoP`s will be
included everywhere (mainly west of I-55 in the morning and east in
the afternoon). Will maintain some chance PoP`s across the east into
evening, until the wave fully passes.
Quiet weather on tap for Monday and Tuesday, as high pressure slowly
builds eastward across the Midwest. Some upper level ridging over
the central U.S. will help temperatures rise into the 60s both days.
As this occurs, an upper low will cut off over the Nevada/Utah area.
Longer range models are a bit split as to how this feature will
interact with a shortwave dropping south through the Canadian
prairies. The ECMWF maintains these as two distinct features until
the Canadian wave digs south and absorbs it on Thursday, while the
GFS draws the energy into the northern wave about 24 hours earlier.
This results in the latter model being a lot stronger with the
development of a surface cyclone over the central Plains. This would
have more of a thunder threat for our area, along with rain moving
out by Thursday morning, while the slower ECMWF focuses more on a
Thursday night through Friday evening period for the rain. Continued
with the highest PoP`s Wednesday night and kept chance PoP`s into
Thursday in most areas except the far west.
Trend late week will be toward a cooler pattern, the core of which
will arrive next weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1127 PM CDT Fri Mar 25 2016
High surface pressure will continue to depart farther away to the
east the rest of tonight. Cirrus clouds are already overspreading
Illinois, with mid clouds in the 10K-12K layer are approaching
from the west. The HRRR and RAP models both show limited potential
for any measurable rainfall near the TAF sites tomorrow. PIA would
have the best chances, but even there looks primarily dry. Will
keep conditions VFR over the next 24 hours.
Southeast winds will begin to increase to 10-14kt in the 15-17z
time frame as the surface pressure gradient tightens ahead of the
next low pressure system. Forecast soundings indicate mid clouds
will increase again later Saturday evening, but better chances of
rainfall look to be delayed until after 12z on Sunday.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...BAK
LONG TERM...Geelhart
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1250 AM CDT SAT MAR 26 2016
.UPDATE...
900 PM CDT
GOING FORECAST IS IN GOOD SHAPE TONIGHT. MOSTLY CLEAR/PARTLY
CLOUDY SKIES WILL ALLOW TEMPERATURES TO FALL TO NEAR OR AROUND
FREEZING IN MOST LOCATIONS...BUT WITH HIGH PRESSURE MOVING EAST WE
WILL MAINTAIN A WIND COMPONENT WHICH WHEN COUPLED WITH SOME CLOUDS WILL
KEEP TEMPERATURES A BIT WARMER TONIGHT THAN LAST NIGHT. LOW
PRESSURE IN THE PLAINS CONTINUES TO PRODUCE SHOWERS AND FEW
THUNDERSTORMS TO OUR WEST. AS THE LOW MOVES EAST TONIGHT INTO
SATURDAY...EXPECT AN INCREASE IN MID AND HIGHER LEVEL CLOUDS. AS
MENTIONED IN EARLIER DISCUSSIONS...THE BULK OF THIS ENERGY REMAINS
TO THE WEST THROUGH THE DAY SATURDAY...WITH THE SURFACE COLD
FRONTAL BOUNDARY WELL NORTH...WHICH OTHER THAN SOME SPRINKLES OR
VERY LIGHT SHOWERS IN NORTHWEST INTO NORTH CENTRAL IL...SATURDAY
SHOULD REMAIN DRY.
KMD
&&
.SHORT TERM...
136 PM CDT
THROUGH SATURDAY...
A SURFACE RIDGE OF HIGH PRESSURE CENTERED ACROSS THE AREA THIS
AFTERNOON CONTINUES TO PRODUCE VERY LIGHT WINDS OVER THE AREA. THIS
LIGHT WIND REGIME WILL LIKELY CONTINUE TO ALLOW TO WINDS TO SHIFT
EASTERLY ALONG AND NEAR THE LAKE FRONT THIS AFTERNOON. OTHERWISE...ALOFT
MOST OF NORTHERN ILLINOIS HAS BEEN MAIN SUNNY TODAY...LOWER CLOUDS
AROUND 2,000 FEET AGL HAVE BEEN SLOW TO DISSIPATE THIS AFTERNOON
ACROSS MY SOUTHEASTERN CWA...MAINLY NORTHWESTERN INDIANA AND
PORTIONS OF EAST CENTRAL ILLINOIS. HOWEVER...THESE CLOUDS SHOULD
CONTINUE TO GRADUALLY DISSIPATE BY EARLY THIS EVENING.
AFTER ANOTHER CHILLY NIGHT TONIGHT...WITH LOWS IN THE LOWER 30S...IT
APPEARS A MUCH MILDER DAY WILL BE SETTING UP ON SATURDAY...ESPECIALLY
WELL INLAND FROM LAKE MICHIGAN. OVERALL...TEMPERATURES LOOK TO TOP
OUT NEAR 60 SOUTH...WITH MID TO UPPER 50S ELSEWHERE...WITH THE
EXCEPTION OF MIDDLE 40S NEAR THE LAKE DUE TO A PERSISTENT ONSHORE
WIND. HIGHER CLOUDS WILL BE ON THE INCREASE LATER TONIGHT INTO
SUNDAY. SO...SKIES LOOK TO BE PARTLY SUNNY DURING THE DAY.
HOWEVER...IT DOES APPEAR THE AREA WILL REMAIN DRY THROUGH THE
DAY...AS IT APPEARS THE RAIN THREAT WILL REMAIN WEST OF THE AREA.
KJB
&&
.LONG TERM...
242 PM CDT
SATURDAY NIGHT THROUGH FRIDAY...
THE FIRST LOW MOVES OVER THE LAKE SUNDAY BRINGING RAIN TO THE
REGION. FORECAST SOUNDINGS FEATURE MINIMAL SATURATION INITIALLY SO
THINKING THE BEST CHANCE OF SHOWERS WILL NOT OCCUR UNTIL SUNDAY
AFTERNOON WHEN THE UPPER LEVEL VORT STREAMER AND COLD FRONT SWING
THROUGH THE REGION. THE EURO IS A BIT SLOWER THAN THE GFS WITH THE
FRONT...BUT THE NAM ALSO FEATURES A SLOWER PROGRESSION. THINKING THE
BEST CHANCE FOR RAIN WILL BE ALONG AND EAST OF I-55 SUNDAY
AFTERNOON. KEPT THUNDER OUT OF THE FORECAST WITH CAPE VALUES LESS
THAN 50 J/KG FROM THE TYPICALLY OVERDONE NAM. THUNDER APPEARS TO BE
A BETTER BET SOUTH OF THE WARNING AREA ACROSS CENTRAL IL AND CENTRAL
INDIANA.
HIGH TEMPS WILL VARY FROM THE UPPER 40S ACROSS NORTH CENTRAL IL TO
THE MID TO UPPER 50S OVER NW INDIANA. TEMPERATURES QUICKLY FALL
BEHIND THE COLD FRONT WITH LOWS IN THE MID TO LOWER 30S OVERNIGHT.
THINKING PRECIP WILL DIMINISH BEFORE TEMPS FALL BELOW FREEZING SO DO
NOT HAVE ANY FROZEN PRECIP IN THE FORECAST. THE NAM FEATURES A FEW
WRAP AROUND SHOWERS...BUT FORECAST SOUNDINGS FEATURE VERY SHALLOW
SATURATION SO DID NOT INCLUDE THESE SHOWERS IN THE FORECAST.
HIGH PRESSURE IS EXPECTED MONDAY THROUGH TUESDAY AFTERNOON. WINDS
WILL BE WEAK AND VARIABLE MONDAY WITH A LAKE BREEZE. TEMPS SHOULD
EASILY WARM INTO THE MID 50S EXCEPT FOR ALONG THE LAKE. 60S ARE
EXPECTED TUESDAY.
THE NEXT SYSTEM FORMS OVER THE PLAINS WEDNESDAY. A SHORTWAVE TROUGH
MOVES ACROSS THE REGION TUESDAY NIGHT INTO WEDNESDAY WITH INCREASING
CHANCES OF RAIN. THE GFS IS MORE AGGRESSIVE WITH PRECIP AND THE
STRENGTH OF THE LOW THAN THE ECMWF. HAVE THE GREATEST CONFIDENCE IN
WIDESPREAD RAIN AND PERHAPS A FEW THUNDERSTORMS WEDNESDAY NIGHT.
COULD ALSO SEE A FEW THUNDERSTORMS WEDNESDAY WHILE WE ARE IN THE
WARM SECTOR OF THE SYSTEM.
OTHER SPECIFICS LIKE HOW GUSTY SOUTH WINDS WILL BE WEDNESDAY DEPEND
ON THE STRENGTH OF THE LOW. DECIDED TO BUMP UP WIND GUSTS TO 30-35
MPH GIVEN THE STRENGTH OF THE GFS LOW...BUT DID SO WITH RESTRAINT DUE
TO MEDIUM CONFIDENCE AT BEST. WEDNESDAY DOES LOOK LIKE THE WARMEST
DAY IN THE EXTENDED WITH HIGHS IN THE MID TO UPPER 60S.
THE LOW PUSHES NORTHEAST THURSDAY WITH A SURFACE HIGH BUILDING
OVERHEAD. HAVE LOW CONFIDENCE IN POPS FROM THURSDAY NIGHT ON BECAUSE
THE UPPER LEVEL TROUGH REMAINS OVER THE REGION. IT COULD FORCE
PERIODS OF SHOWERS AS IT ROTATES THROUGH. COLDER CONDITIONS DO LOOK
LIKELY FRIDAY AS THE TROUGH AND COOLER UPPER LEVEL AIR MOVE OVERHEAD.
JEE
&&
.AVIATION...
FOR THE 06Z TAFS...
HIGH PRESSURE CENTERED OVER LAKE ONTARIO AND THE ST. LAWRENCE
VALLEY WILL MOVE NORTHEASTWARD TODAY WHILE LOW PRESSURE MOVES FROM
THE SOUTHERN HIGH PLAINS INTO IOWA BY THIS EVENING. LIGHT
SOUTHEAST WINDS ARE IN PLACE ACROSS THE TERMINALS AND WILL BE
SHIFTING A BIT MORE SOUTHERLY OVERNIGHT. THE FLOW WILL BE WEAK
ENOUGH THROUGH THE DAY TO ALLOW LAKE INFLUENCES TO TAKE OVER
TURNING WINDS EASTERLY MID/LATE AFTERNOON AND PROBABLY EAST-
NORTHEASTERLY AT TIMES AT ORD/MDW AND EVENTUALLY DPA. GYY IS A
BIT MORE OF A WILDCARD AND MAY STAY EAST TO SOUTHEAST THOUGH A
SHIFT TO NORTHEAST MAY BE SLIGHTLY FAVORED. VFR WILL PREVAIL WITH
VARIABLE MID AND HIGH CLOUD COVERAGE. WINDS WILL WORK THEIR WAY
BACK TO SOUTHEAST MID TO LATE EVENING THEN TURN SOUTH SUNDAY
MORNING AS SURFACE LOW PRESSURE DRIFTS INTO SOUTHWESTERN
WISCONSIN. ANY CHANCES FOR SHOWERS LOOK TO HOLD OFF UNTIL AT LEAST
SUNDAY MORNING WHEN A SHARPER UPPER TROUGH APPROACHES FROM THE
SOUTHWEST.
MDB
&&
.MARINE...
242 PM CDT
HIGH PRESSURE IS OVERHEAD WITH LIGHT FLOW AT THE SURFACE. A WEAK
LAKE BREEZE HAS FORMED AND PUSHED WELL INLAND. WINDS BECOME SOUTH
AND INCREASE TO 20 KT OVER THE NORTHERN HALF OF THE LAKE WHILE THE
WINDS ACROSS THE REST OF THE LAKE BECOME SOUTHEAST TO 15 KT. WINDS
BECOME SOUTHEAST 10-20 KT ACROSS THE LAKE BY SATURDAY EVENING. A
WEAK LOW MOVES OVER THE NORTHERN END OF THE LAKE SUNDAY WITH WINDS
BECOMING NORTHWEST/NORTH TO 20 KT BEHIND IT SUNDAY EVENING. ANOTHER
HIGH MOVES OVER THE LAKE MONDAY WITH WEAK AND VARIABLE WINDS ACROSS
THE LAKE. A LAKE BREEZE IS EXPECTED. SOUTH WINDS INCREASE BEHIND
THE HIGH TUESDAY NIGHT AND THE NEXT LOW FORMS OVER THE PLAINS.
GUIDANCE HAS SIGNIFICANT DIFFERENCES IN THE NEXT LOWS STRENGTH. THE
GFS FEATURES A 28.8 INCH LOW WHILE THE ECMWF HAS A 29.2 INCH LOW
BOTH OVER NORTHERN LAKE MI AND LAKE SUPERIOR. RAISED WIND SPEEDS
ACROSS THE LAKE TO 30 KT THURSDAY AND TO GALES OVER THE NORTHERN END
OF THE LAKE. CONFIDENCE IS LOW GIVEN THE MODEL DISAGREEMENT.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
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Area Forecast Discussion
National Weather Service Lincoln IL
1127 PM CDT FRI MAR 25 2016
.UPDATE...
Issued at 900 PM CDT Fri Mar 25 2016
Forecast grids looking on track as low pressure slides east
tonight and tomorrow. Mid and high clouds are expected to increase
later tonight as the next low pressure system approaches the
western Great Lakes. Despite the increasing clouds, low temps
should bottom out near seasonal normals in the mid to upper 30s.
A few sprinkles may develop from time to time west of I-55,
however, most areas will remain dry. Rain chances still look to be
increasing quickly Easter Sunday morning west of I-55, then
progressing eastward through the day.
Only minor updates this evening were to the sky grids. Updated
forecast info is already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 300 PM CDT Fri Mar 25 2016
High pressure ridge currently stretching from the lower Mississippi
River Valley up into the Great Lakes will maintain control over the
region for the overnight hours. As the axis slips to the east,
increasingly south/southeasterly winds will increase towards
sunrise, but staying light overall. Clearing cu from this afternoon
will leave some remnant low level moisture that may result in some
low level clouds in the east, but for the most part, the sky will be
dominated with some thin cirrus from the SW. Quiet tonight, and
chilly, but not quite as cold.
.LONG TERM...(Saturday through Friday)
ISSUED AT 300 PM CDT Fri Mar 25 2016
Models still not handling the Easter Sunday system very well, though
all of them keep most of the pcpn with the first wave Sat afternoon
and evening west of the CWA. The handling of the main wave, on
Sunday, still has the ECMWF and NAM similar, as the GFS is little
further east and quicker with pushing the pcpn through. So, will
continue with a ECMWF/NAM type blend with this forecast, which
should look similar to previous forecasts. So, will have a slight
chance of showers Sat night in the west half of the CWA and then
likely for Sunday. With all models going with an open-wave Sunday,
believe isolated thunderstorms over the whole area is possible. With
going with the NAM/ECMWF models, pcpn will remain possible Sun night
with highest pops in the east during the evening. Pcpn will then
quickly pus east late Sun night. All pcpn should be liquid given
that colder air will not arrive til probably after the pcpn is
gone...so no snow in this forecast.
After a dry period from Mon night through Tue, another weather
system is forecast to move into the area for mid week.
ECMWF/GFS/Canadian differ on onset/timing of pcpn and the associated
synoptic pattern, so will just go with the blend of the extended
models, hoping they will come into better agreement later.
Temps will be around normal this weekend, with coldest lows Sun
night/Mon morning. However, warmer/slightly above normal temps can
be expected next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1127 PM CDT Fri Mar 25 2016
High surface pressure will continue to depart farther away to the
east the rest of tonight. Cirrus clouds are already overspreading
Illinois, with mid clouds in the 10K-12K layer are approaching
from the west. The HRRR and RAP models both show limited potential
for any measurable rainfall near the TAF sites tomorrow. PIA would
have the best chances, but even there looks primarily dry. Will
keep conditions VFR over the next 24 hours.
Southeast winds will begin to increase to 10-14kt in the 15-17z
time frame as the surface pressure gradient tightens ahead of the
next low pressure system. Forecast soundings indicate mid clouds
will increase again later Saturday evening, but better chances of
rainfall look to be delayed until after 12z on Sunday.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...HJS
LONG TERM...Auten
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1228 AM EDT SAT MAR 26 2016
.SYNOPSIS...
LOW PRESSURE WILL MOVE INTO NEW BRUNSWICK TONIGHT. HIGH PRESSURE
WILL BUILD ACROSS THE REGION SATURDAY...AND THEN MOVE SLOWLY EAST
SUNDAY. LOW PRESSURE WILL PASS SOUTH OF THE AREA MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TODAY/...
1228 AM UPDATE...LOW STRATUS HOLDING TIGHT ACROSS THE NORTHERN
AND WESTERN ZONES EARLY THIS MORNING WITH A P/CLOUDY SKY DOWNEAST.
SOME SPOTTY FREEZING DRIZZLE OR A FEW FLURRIES POSSIBLE OUT OF THE
STRATUS, BUT NOTHING SIGNIFICANT EXPECTED THE REMAINDER OF THE
NIGHT. THE LOW CLOUDS WILL BEGIN TO BREAK UP TOWARD MORNING. ONLY
MINOR TWEAKS TO THE ONGOING FORECAST BASED ON THE MIDNIGHT
OBSERVATIONS AND LATEST SATELLITE TRENDS.
PREVIOUS DISCUSSION... STAYED WITH THE HRRR 3KM AND GEM MODEL
BLEND FOR PRECIP AND TEMPS FOR THIS PACKAGE. ADDITIONAL ONE TENTH
OF AN INCH OF ICE EXPECTED ACROSS THE FAR NORTH.
THE ICING THREAT WILL END BY EARLY EVENING AS LOW PRES PULLS
TOWARD NEW BRUNSWICK W/SOME SNOW ON THE BACKSIDE AS COLD AIR MOVES
IN AT MID LEVELS. LLVLS WILL COOL DOWN OVERNIGHT AS THE UPPER TROF
SWINGS ACROSS THE REGION. NNW WINDS WILL PICK UP THIS EVENING AS
THE LOW MOVES INTO NEW BRUNSWICK W/SOME GUSTS TO 20 MPH. ANY
ADDITIONAL SNOW WILL BE NO MORE THAN 1/2 INCH. TEMPS WILL FALL
BACK W/SOME CLEARING AFTER MIDNIGHT AS READINGS HIT THE MID AND
UPPER TEENS ACROSS THE NORTH AND WEST W/LOW TO MID 20S ELSEWHERE.
THIS COULD LEAD TO SOME RE-FREEZING OF SURFACES OVERNIGHT.
HIGH PRES IS FORECAST TO SLIDE ACROSS THE REGION FROM QUEBEC ON
SATURDAY. THERE WILL BE SUNSHINE TO ALLOW FOR SOME MELTING, BUT IT
LOOKS AS THOUGH TEMPS WILL BE AROUND NORMAL FOR LATE MARCH. THIS
BEING BASED ON THE ORIENTATION OF THE HIGH AND A ZONAL FLOW ALOFT.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
SATURDAY NIGHT RETURN FLOW OFF THE GULF OF MAINE BECOMES
ESTABLISHED WITH THE POSSIBILITY OF A DEEP LOW LEVEL STRATUS LAYER
MOVING ON-SHORE DURING THE DAY ON SUNDAY.THIS COULD LEAD TO SOME
PATCHY DRIZZLE ON THE COAST AND MAYBE SOME LIGHT FREEZING DRIZZLE
BY SUNDAY NIGHT. CHANCE OF ICE PELLETS/FREEZING RAIN AND FREEZING
DRIZZLE INCREASE TOWARDS MONDAY MORNING AS NEXT WEATHER MAKER
BEGINS TO PUSH INTO THE STATE. A SAINT LAWRENCE VALLEY SURFACE LOW
IS EXPECTED TO TRANSFER ITS ENERGY TO A LOW DEVELOPING OVER
SOUTHERN NEW ENGLAND DURING THE DAY ON MONDAY. LOW LEVEL
TEMPERATES ARE EXPECTED TO RISE ABOVE FREEZING WITH RAIN SHOWERS
EXPECTED MONDAY MORNING. STILL SOME SPREAD IN THE MODELS WITH THE
STRENGTH OF THE DEVELOPING COASTAL LOW...WHICH COULD SUBSTANTIALLY
INCREASE THE RAIN MONDAY AFTERNOON AND WIND SPEEDS. THE GFS SEEMS
TO BE AN OUTLIER WITH A WEAK COASTAL LOW BUT THE SREF/NAM/EC/CMC
ALL HAVE THE COASTAL LOW BECOMING THE PRIMARY DURING THE DAY ON
MONDAY. WILL HAVE TO WATCH THIS OVER THE NEXT FEW DAYS FOR A
SUBSTANTIAL INCREASE IN THE QPF FORECAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE ALOFT ALONG THE EAST COAST SUNDAY NIGHT GIVES WAY TO
AN APPROACHING UPPER TROUGH MONDAY AND MONDAY NIGHT. A COLD FRONT
IS EXPECTED TO BRING RAIN AND WET SNOW MONDAY INTO MONDAY NIGHT. THE
12Z EC AND TO A LESSER EXTENT THE CANADIAN SUGGEST A WET SNOW EVENT
ACROSS NORTHWEST MAINE WITH A RAPIDLY DEEPENING COASTAL LOW ALONG
THE FRONTAL BOUNDARY.
IT WILL BE ABOVE 10 DEGREES COLDER ON TUESDAY IN NORTHWEST FLOW
ALOFT ON TUESDAY. THERE MAY BE INSTABILITY SNOW SHOWERS ACROSS THE
CROWN OF MAINE.
HIGH PRESSURE ALOFT BUILDS IN FOR WEDNESDAY AND THURSDAY. IT SHOULD
BE MUCH WARMER ACROSS DOWNEAST AND CENTRAL MAINE. NOT SO SURE
ABOUT NORTHERN MAINE AT THE TOP OF THE RIDGE AXIS. A STRONG COLD
FRONT IS FORECAST TO SWING THROUGH LATE IN THE FORECAST PERIOD
WITH A CHANCE OF SHOWERS.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: IFR RESTRICTIONS EXPECTED FOR CAR, PQI AND HUL THROUGH
AROUND 05Z SAT LIFTING TO LOW MVFR BY 12Z. MVFR CIGS AT FVE WILL
BECOME VFR BY 12Z. IFR CIGS AT BGR AND BHB HAVE SCATTERED OUT TO
LOW MVFR OR VFR. EXPECT THIS WILL REMAIN THE CASE THROUGH THE
OVERNIGHT. VFR ALL TERMINALS SATURDAY AS HIGH PRESSURE BUILDS IN
FROM QUEBEC.
SHORT TERM: LOW LEVEL STRATUS LAYER EXPECTED BY SUNDAY WHICH
COULD LEAD TO SOME IFR CEILINGS. CHANCE FOR SOME LIGHT FREEZING
RAIN ACROSS THE NORTHERN TAF TERMINALS LATE SUNDAY NIGHT INTO
MONDAY MORNING. LOW CEILINGS AND VISIBILITY EXPECTED TO CONTINUE
THROUGH THE DAY ON MONDAY IN RAIN.
&&
.MARINE...
NEAR TERM: CANCELLED SCA AS SEAS ARE BELOW 5 FEET AND WINDS ARE
LIGHT OUT OF THE W. SEAS WILL BUILD TO AROUND 5 FEET ON SATURDAY
AND WIND GUST WILL APPROACH SCA CRITERIA SO HAVE RE-ISSUED FOR
SAT.
SHORT TERM: HIGH PRESSURE OVER THE WATERS ON SUNDAY WITH A SOUTHERLY
RETURN FLOW DEVELOPING. WINDS AND SEAS WILL STAY BELOW SCA. WE ARE
WATCHING FOR A POSSIBLE GULF OF MAINE LOW PRESSURE DEVELOPING ON
MONDAY...CONFIDENCE IS STILL LOW AT THIS TIME ON THIS STORM.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM EARLY THIS MORNING TO 6 PM EDT
THIS EVENING FOR ANZ050-051.
&&
$$
NEAR TERM...CB/FARRAR/HEWITT
SHORT TERM...DUMONT
LONG TERM...OKULSKI
AVIATION...CB/FARRAR/HEWITT/DUMONT
MARINE...CB/FARRAR/HEWITT/DUMONT
AREA FORECAST DISCUSSION
NWS DULUTH MN
356 AM CDT SAT MAR 26 2016
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 356 AM CDT SAT MAR 26 2016
A STATIONARY FRONT FROM A LOW IN THE CENTRAL PLAINS WILL CONTINUE
TO EXTEND THROUGH THE SE FORECAST AREA THROUGH TONIGHT AS THE LOW
LIFTS GRADUALLY INTO THE UPPER MIDWEST. THERE WILL BE COOLER NE
FLOW ON THE NORTHERN AND WESTERN SIDE OF THE FRONT. A WAVE OF
PCPN EARLY THIS MORNING...ASSOCIATED WITH A PASSING
SHORTWAVE...WILL GRADUALLY TAPER OFF LATER THIS MORNING.
HOWEVER...ANOTHER WAVE OF PCPN WILL LIFT INTO THE NORTHLAND
TONIGHT WHEN THE LOW MOVES INTO IOWA AND SE MINNESOTA/SW
WISCONSIN.
SURFACE TEMPERATURES WILL CLIMB TO THE 30S AND 40S TODAY...WITH
THE WARMEST TEMPERATURES ACROSS THE FAR SOUTHERN FORECAST AREA IN
THE WARM ZONE SOUTH AND EAST OF THE STATIONARY FRONT. TEMPERATURES
WILL THEN DIP INTO THE 20S AND 30S OVERNIGHT. THE RAP/NAM/GFS
MODEL SOUNDINGS INDICATE DEEP ENOUGH SATURATION THROUGH TONIGHT TO
RELIABLY FAVOR SNOW...EXCEPT WHERE NEAR SURFACE TEMPERATURES WILL
BE SUFFICIENTLY ABOVE FREEZING TO FAVOR RAIN. MUCH OF THE
LINGERING MIDDAY VERY LIGHT PCPN WILL LIKELY BE RAIN...EXCEPT
PERHAPS A MIX OF RAIN AND SNOW NEAR LAKE SUPERIOR. THE RAIN WILL
THEN TRANSITION BACK TO SNOW LATE THIS AFTERNOON AND THIS EVENING
WITH THE FALLING TEMPERATURES AND NEXT WAVE OF PCPN. SOME AREAS OF
THE NORTHLAND MAY GET 1 TO 3 INCHES OF SNOW ACCUMULATION
TONIGHT...INCLUDING THE NORTH AND SOUTH SHORES...THE TWIN PORTS
AND CLOQUET AREAS...AND TO NEAR AITKIN.
THERE COULD BE NARROW CORRIDOR OF SLEET TONIGHT NEAR THE
STATIONARY FRONT BETWEEN THE ZONES OF PREDOMINATELY RAIN AND
PREDOMINATELY SNOW. THERE COULD BE A CORRIDOR WHERE THE SNOW FALLS
THROUGH A WARM ENOUGH LAYER TO RESULT IN MELTING...THEN FALL BACK
INTO A SHALLOW COLD LAYER TO CAUSE SOME REFREEZING. HOWEVER...BASED
ON THE GFS/NAM SOUNDINGS...THE THREAT LOOKED TOO UNLIKELY OR TOO
NARROW IN COVERAGE TO CONSIDER ADDING THAT DETAIL TO THE FORECAST
AT THIS POINT. THE DAY SHIFT WILL HAVE A BETTER ABILITY TO
DETERMINE ITS THREAT WHEN THE RAP AND HRRR EXTEND THROUGH
TONIGHT.
THE NE FLOW OFF OF LAKE SUPERIOR...AND HIGH RELATIVELY HUMIDITY
TONIGHT...WILL LIKELY CAUSE MISTY CONDITIONS ACROSS LARGE PORTIONS
OF THE NORTHLAND. FOG IS POSSIBLE IN SOME AREAS...SUCH AS IN THE
HIGHER TERRAIN NEAR THE TWIN PORTS AND ASHLAND AREAS DOWNWIND AND
NEAR LAKE SUPERIOR. HOWEVER...WAS NOT CONFIDENT ENOUGH YET TO
INCLUDE IN THE FORECAST.
THE LOW WILL LIFT FROM WISCONSIN INTO MICHIGAN SUNDAY. THERE MAY
BE LINGERING LIGHT SNOW AND RAIN SUNDAY MORNING...BUT THE PCPN
SHOULD COME TO AN END BY NOON. THERE SHOULD ALSO BE SOME CLEARING
SKIES FROM THE WEST AS SURFACE HIGH PRESSURE MOVES INTO THE
REGION AND IN THE WAVE OF A PASSING SHORTWAVE TROUGH. INCREASED
TEMPERATURES...LEANING MORE ON THE WARMER NAM MOS COMPARED TO THE
COOLER GFS MOS CONSIDERING THE FAVORABILITY FOR WARMING FROM THE
SUNSHINE. A SUBTLE COLD FRONT WILL BEGIN TO MOVE INTO THE WESTERN
FORECAST AREA DURING THE LATE AFTERNOON OR EARLY EVENING.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 356 AM CDT SAT MAR 26 2016
THE FOCUS DURING THE EXTENDED PERIOD WILL BE ON A STRONG EARLY
SPRING STORM MID WEEK.
THE UPPER FLOW WILL START OUT NORTHWESTERLY OVER THE
NORTHLAND...WITH AN UPPER LOW OVER THE PACIFIC NORTHWEST. A
SHORTWAVE AND WEAK SURFACE LOW WILL MOVE THROUGH THE NORTHLAND
SUNDAY NIGHT. MOST OF THE MODELS DO NOT INDICATE MUCH PRECIP WITH
THESE FEATURES...BUT WE DO KEEP A LOW CHANCE FOR SOME SNOW/RAIN
OVER PARTS OF THE NORTHLAND AS IT MOVES THROUGH.
MONDAY AND MONDAY NIGHT SHOULD BE DRY WITH WEAK HIGH PRESSURE
PASSING THROUGH THE AREA.
THE UPPER LOW WILL DROP SOUTH OVER THE GREAT BASIN MONDAY NIGHT
THEN THE MODELS MOVE IT SLOWLY EAST INTO WEDNESDAY. A PIECE OF
SHORTWAVE ENERGY WILL MOVE NORTHEAST OUT OF THE LOW AND DEEPEN A
SURFACE LOW. THE NORTHLAND WILL START TO FEEL THE IMPACTS OF THESE
FEATURES AS EARLY AS TUESDAY...WITH A CHANCE FOR LIGHT SNOW/RAIN
OVER MAINLY SOUTHERN PORTIONS OF THE AREA. MODEL DIFFERENCES START
SHOWING UP TUESDAY...AND INCREASE THROUGH THE REMAINDER OF THE
PERIOD. SOME OF THE DIFFERENCES INCLUDE THE GFS MERGING A NORTHERN
STREAM WAVE WITH THE SOUTHERN STREAM WAVE ON WEDNESDAY DEEPENING
THE SURFACE LOW MUCH MORE THAN THE ECMWF/GEM. ALSO AS A RESULT OF
THE DEEPER LOW...IT IS MUCH SLOWER. ALL THE MODELS HAVE SHOWN BOTH
RUN TO RUN DIFFERENCES AS WELL AS DIFFERENCES IN HOW THEY HANDLE
THIS LOW. THE GFS HAS TRENDED FASTER AND A BIT WEAKER WITH THE
SURFACE LOW FROM 108-120 HOURS COMPARED WITH PREVIOUS RUNS.
PRECIPITATION SHOULD BECOME LIKELY FOR MOST OF THE AREA TUESDAY
NIGHT/WEDNESDAY THEN GRADUALLY DECREASE FROM WEST TO EAST
WEDNESDAY NIGHT INTO THURSDAY. THE ECMWF IS MORE PROGRESSIVE
MOVING THROUGH LOW THROUGH THE REGION...AS IT KEEPS THE NORTHERN
STREAM WAVE SEPARATE WHICH HELPS MOVE THE LOW ALONG.
PRECIPITATION TYPE WILL BE A TOUGH CALL...EVEN IN THE SHORT
TERM...BUT ESPECIALLY THIS FAR OUT WITH ALL THE MODEL DIFFERENCES.
WE HAVE A RAIN/SNOW MIX OVER NORTHERN AREAS OF MINNESOTA TUESDAY
NIGHT AND OVER PARTS OF THE FAR NORTH ON WEDNESDAY. COLDER AIR
WILL MOVE IN WEDNESDAY NIGHT INTO THURSDAY WITH A BETTER CHANCE
FOR SNOW. A FEW THUNDERSTORMS MAY ALSO OCCUR...MAINLY WEDNESDAY
INTO WEDNESDAY NIGHT. SIGNIFICANT PRECIPITATION WILL BE LIKELY
WITH THIS STORM...BUT JUST HOW MUCH SNOW OCCURS IS VERY DIFFICULT
TO DETERMINE AT THIS TIME. IF THE GFS VERIFIES...THERE WILL BE A
BETTER CHANCE FOR SIGNIFICANT SNOWFALL OVER MAINLY NORTHEAST
MINNESOTA.
MODEL DIFFERENCES CONTINUE THROUGH THE REST OF THE EXTENDED AS
WELL. HOWEVER...BOTH THE GFS AND ECMWF SHOW VERY COLD AIR MOVING
INTO THE REGION OVER THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1229 AM CDT SAT MAR 26 2016
A FRONTAL BOUNDARY WILL SLOWLY PUSH SOUTH OVER THE WESTERN LAKE
SUPERIOR REGION OVERNIGHT...TRACKING ACROSS NORTHERN WISCONSIN
THROUGH SATURDAY AFTERNOON. THIS FRONT WILL BE THE FOCUS FOR RAIN
AND SNOW SHOWERS...ALONG WITH MVFR/IFR FLIGHT CONDITIONS.
PRECIPITATION TYPE WILL VARY ACROSS THE NORTHLAND TONIGHT...WITH
MAINLY SNOW OVER FAR NORTHERN MINNESOTA AND RAIN OR SNOW FURTHER
SOUTH. AS PRECIPITATION INTENSITY INCREASES...A CHANGE TO MAINLY
SNOW WILL OCCUR. A WARMING BOUNDARY LAYER ON SATURDAY WILL CAUSE
MORE RAIN TO OCCUR...ESPECIALLY OVER THE SOUTHERN HALF OF THE
NORTHLAND.
A SECONDARY WAVE WILL LIFT ACROSS CENTRAL MINNESOTA AND INTO THE
FORECAST AREA SATURDAY EVENING...BRINGING LOWERING CEILINGS AND
ANOTHER ROUND OF SHOWERS. LATEST PROFILES SUGGEST A PERIOD OF
SLEET OR BRIEF FREEZING RAIN MAY MIX WITH THE SNOW DURING THE
EVENING HOURS FOR LOCATIONS GENERALLY SOUTH OF US HIGHWAY
2...INCLUDING KBRD/KDLH/KHYR. THIS WILL BE MONITORED BY LATER
SHIFTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 36 28 43 27 / 70 80 20 20
INL 38 17 44 23 / 0 0 0 10
BRD 41 29 49 30 / 50 60 0 0
HYR 45 33 47 28 / 70 80 30 10
ASX 39 30 41 29 / 80 80 40 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 10 PM CDT THIS
EVENING FOR LSZ121-140>143-146>148.
SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 4 AM CDT SUNDAY
FOR LSZ144-145.
&&
$$
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...GRANING
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1139 PM CDT FRI MAR 25 2016
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 316 PM CDT FRI MAR 25 2016
MAIN FORECAST CHALLENGE THROUGH SATURDAY DEALS WITH A COLD FRONT AND
SHORTWAVE PASSAGE FRIDAY NIGHT. MID LEVEL CLOUDINESS HAS BEEN RATHER
THICK THROUGHOUT THE DAY WITH A FEW LIGHT SHOWERS ACROSS FAR
NORTHWEST NEBRASKA... MAINLY CONFINED TO THE PINE RIDGE. WEAK RADAR
ECHOES HAVE BEEN OBSERVED OVER SOUTHWEST NEBRASKA... BUT WITH DEW
POINT DEPRESSIONS AROUND 25F... ONLY RESULT IS VIRGA.
THIS EVENING AND TONIGHT... MID LEVEL FRONTOGENESIS INCREASES AS THE
SHORTWAVE APPROACHES NORTHERN NEBRASKA AND MOISTURE SLOWLY WORKS
TOWARD THE SURFACE. REMOVED MENTION OF SPRINKLES SOUTH OF NEB HWY 2
AS LIFT IN THE LOWER 200HPA DISAPPEARS. THROUGH 06Z... BEST
SATURATION AND LIFT EXIST ACROSS NORTHERN SHERIDAN AND NORTHWEST
CHERRY COUNTIES... SO RETAINED LIKELY POPS FOR A SMALL AREA ALONG
THE SD BORDER. HRRR HINTS AT SOME SHOWER ACTIVITY FARTHER EAST... SO
EXTENDED SCHC POPS SOUTH TOWARD KTIF AND EAST TOWARD KONL. NAM
FORECAST SOUNDINGS INDICATE A SWITCH TO SNOW AT MERRIMAN AROUND 03Z
AND VALENTINE AROUND 05Z. USED A GRADUAL TRANSITION FROM RA TO RASN
TO SN FROM WEST TO EAST.
SNOWFALL WISE... SOUNDINGS AT KVTN SHOW THE BULK OF THE MOISTURE
BELOW 600HPA THROUGH THE NIGHT AND LIFT BELOW 800HPA... WHERE THE
DGZ GENERALLY LINES UP WITH 600-700HPA. TEMPERATURES SLOWLY FALL
FROM THE 30S INTO THE 20S WHICH WILL LIMIT SLR. START AROUND 10:1
FOR 06-12Z AND INCREASE TO NEAR CLIMO... 12-13:1... BY LATE MORNING.
TOTAL ACCUMULATIONS ARE AROUND 1 INCH ALONG AND NORTH OF HWY 20 WEST
OF KVTN AND A DUSTING FROM KAIA TO KONL.
HAVE WINDS PICKING UP QUITE A BIT WITH THE FROPA. NAM INDICATING
850HPA WINDS NEAR 35KTS AND A 1MB/HR PRESSURE CHANGE. MECHANICAL
FORCING WILL BRING MUCH OF THIS TO THE SURFACE AND WILL LIKELY
INHIBIT BOUNDARY LAYER DECOUPLING. STRONG CAA IS EVIDENT WITH 850HPA
TEMPS DROPPING FROM 1C AT KLBF AT 06Z TO NEAR -5C BY 12Z. ALSO...
SREF PROBABILITIES ARE HIGH FOR STRATUS DEVELOPMENT BEHIND THE
FRONT. CONFIDENCE IS RATHER LOW ON HOW THESE FACTORS WILL BALANCE...
SO MADE LITTLE CHANGE TO MIN TEMPS. OVERALL... FORECAST LOWS ARE
VERY CLOSE TO MAV AND MET GUIDANCE.
SATURDAY... MAX TEMPS WILL BE ON THE COOL SIDE AS BLUSTERY NORTH
WINDS AND SLOWLY DECREASING CLOUD COVER ACCOMPANY SUBZERO H85 TEMPS.
FORECAST HIGHS ARE GENERALLY 2-3F BELOW MOS GUIDANCE WITH UPPER 30S
NORTH AND LOWER 40S SOUTH. NEARLY SATURATED ENVIRONMENT AND WEAK
LIFT WILL CONTRIBUTE TO LIGHT PRECIP CHANCES ACROSS NORTH CENTRAL
NEBRASKA THROUGH THE DAY. KONL TEMP PROFILE MAINLY SUPPORTS SNOW IN
THE AFTERNOON... BUT WITH HIGHS IN THE UPPER 30S AND SFC WET BULB
ABOVE 0C... TRANSITIONED BACK TO RASN MIX.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 316 PM CDT FRI MAR 25 2016
SATURDAY NIGHT THROUGH MONDAY...A BUILDING THERMAL RIDGE TAKES HOLD
ON THE FCST AREA FROM THE WEST. THE LATEST BLEND OF 4 GUIDANCE DATA
SETS PLUS BIAS CORRECTION PRODUCES HIGHS IN THE UPPER 50S TO LOWER
60S SUNDAY. THE EKD...ECE...MEX GUIDANCE BLEND PLUS BIAS CORRECTION
FOR MONDAY PRODUCES HIGHS IN THE MID TO UPPER 60S.
FULL SUN IS EXPECTED SUNDAY WITH PARTLY CLOUDY SKIES MONDAY AS SOME
MID AND HIGH CLOUDS DRIFT IN FROM A DEVELOPING UPPER LOW OVER THE
WRN U.S.. WEST WINDS SUNDAY SUPPORT DEEPER MIXING THAN THE SOUTH
WINDS AND INCREASING MOISTURE MONDAY. SO DESPITE THE WARMER AIR
ALOFT HIGHS MONDAY ARE FAIRLY MODEST. THE FORECAST IS DRY.
THE FORECAST AREA REMAINS IN THE GRIP OF ARCTIC AIR SATURDAY NIGHT
WHICH PRODUCES LOWS IN THE TEENS TO LOWER 20S. THE THERMAL RIDGE
BUILDS TO NEAR 10C AT 850MB SUNDAY NIGHT WHICH SUPPORTS LOWS IN THE
UPPER 20S TO LOWER 30S.
MONDAY NIGHT THROUGH FRIDAY...A HOT PROD REACHES INTO THE FCST AREA
TUESDAY AND H850MB TEMPERATURES SPIKE REACHING 16C TO 20C. THE GFS
IS FARTHER NORTH THAN THE ECM WHICH BACKS A COLD FRONT INTO NRN NEB.
A BLENDED APPROACH PRODUCES HIGHS IN THE 70S SOUTH AND 60S TO NEAR
70 NORTH.
AN UPPER LOW WILL DRIFT THROUGH THE ROCKIES TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT. A PIECE OF THE LOW LIFTS THROUGH THE CENTRAL HIGH
AND NRN PLAINS. THE MODELS SUGGEST THE MIDLEVEL FRONTOGENESIS WILL
BE FAR ENOUGH SOUTH TO PRODUCE RAIN OR SNOW ACROSS NWRN NEB.
THERE IS ALSO THE POTENTIAL FOR THUNDERSTORMS EAST OF HIGHWAY 83
TUESDAY NIGHT AND WEDNESDAY AS A DRYLINE SHARPENS UP AS A RESULT OF
THE HOT PROD TUESDAY. THE ECM AND GFS SHOW SOME SORT OF CONVECTION
FORMING AS A RESULT. MOST OF THIS IS EAST OF THE FCST AREA. THE
SHEAR IS STRONG WITH H500MB WINDS INCREASING TO 50 TO 70KT.
A FRESH BATCH OF ARCTIC AIR WILL SPILL INTO THE FCST AREA TUESDAY
NIGHT AND WEDNESDAY. UPPER LEVEL SUPPORT CONTINUES DURING THIS TIME
AND RAIN OR SNOW SHOWERS ARE POSSIBLE ASSOCIATED WITH COLD AIR
ALOFT...500MB TEMPERATURES AROUND -25C TO -30C.
THE MODELS ARE IN EXCELLENT AGREEMENT THURSDAY AND FRIDAY. THE DEEP
LOW PRESSURE CIRCULATING THROUGH THE PLAINS WEDNESDAY LIFTS INTO
ONTARIO FORMING A DEEP UPPER LEVEL LOW WHICH CONTINUES TO PULL LATE
SEASON ARCTIC AIR INTO THE FCST AREA. HIGHS THESE DAYS MOSTLY IN THE
40S TO LOWER 50S ARE BELOW NORMAL AS IS THE 6 TO 14 DAY OUTLOOK FROM
CPC.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1139 PM CDT FRI MAR 25 2016
ACROSS NORTHWEST NEBRASKA NEAR KCDR AND KIEN LIGHT SNOW AND IFR
CEILINGS OCCURRING. BETTER MOISTURE WILL OVERSPREAD THE AREA
OVERNIGHT BEHIND AN ADVANCING COLD FRONT...WHICH WILL RESULT IN
IFR/MVFR CIGS AT KVTN AND MVFR CEILINGS AT KLBF. SOME SNOW
SHOWERS ARE POSSIBLE ACROSS NORTHERN NEBRASKA...MAINLY AFFECTING
KVTN...KANW...AND KONL. CEILINGS SHOULD INPROVE TO VFR BY 18Z.
NORTHWEST WINDS WILL ALSO STRENGTHEN OVERNIGHT AND CONTINUE
SATURDAY...WITH GUSTS EXCEEDING 20 KTS.
&&
.FIRE WEATHER...
ISSUED AT 316 PM CDT FRI MAR 25 2016
TUESDAY COULD BE AN OPPORTUNITY FOR FIRE. THE GFS AND ECM BRING A
WARM SPOKE OF DRY AIR NORTH INTO AREAS ALONG AND WEST OF HIGHWAY
83 WHICH COULD RESULT IN HUMIDITY NEAR OR BELOW 15 PERCENT. WINDS
BECOME SOUTH SOUTHWEST IN THE WARM DRY AIR AND INCREASE TO AROUND
20 MPH IMPLYING GUSTS TO 30 MPH. THE ECM IS SLOWER THAN THE GFS
AND DELAYS THE DRY AIR UNTIL TUESDAY EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SNIVELY
LONG TERM...CDC
AVIATION...ROBERG
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
114 AM EDT SAT MAR 26 2016
.SYNOPSIS...
HIGH PRESSURE WILL BUILD SOUTH INTO THE AREA OVERNIGHT BEFORE
WEDGING IN ALONG THE EASTERN SLOPES OF THE APPALACHIANS SATURDAY
INTO SUNDAY. THE NEXT COLD FRONT APPROACHES THE REGION LATE SUNDAY
NIGHT AND CROSSES THROUGH THE AREA DURING THE DAY MONDAY. WEAK
HIGH PRESSURE FOLLOWS THIS FRONT WITH OVERALL DRY WEATHER INTO
MIDWEEK.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1135 PM EDT FRIDAY...
STILL SEEING LINGERING MOISTURE WITH FRONTAL BOUNDARY OVER
SOUTHSIDE VA INTO NC. MAY SEE AN ISOLATED SHOWERS EAST OF DANVILLE
AND REIDSVILLE THROUGH 1AM. OTHERWISE LOOKING AT STRUGGLE TO CLEAR
OUT EAST WITH FRONT SLOW TO MOVE AND HIGH CLOUDS POURING IN FROM
THE SOUTHERLY FLOW ALOFT. WILL SEE SOME CLEARING WITH MORE CLOUDS
ARRIVING TOWARD DAWN. THE WEST WILL SEE THE LOWER CLOUDS STAY
AROUND ON THE WRN SLOPES OF SE WV TO FAR SW VA TIL 4AM THEN CLEAR
SOME TOWARD DAWN.
PREVIOUS DISCUSSION FROM LATE AFTERNOON...
FRONTAL BOUNDARY SITUATED FROM WRN NC NORTHEAST TO THE TIDEWATER OF
VIRGINIA. SOME SHOWERS STILL LINGERING OVER SOUTHSIDE VA INTO THE
NC PIEDMONT. THE 18Z LOCAL WRF AND 21Z HRRR HANDLED THIS PRETTY
WELL SO KEEPING LOW CHANCE/SCATTERED POPS IN THE SOUTHEAST
FORECAST AREA FROM THE TRIAD OF NC TO THE DANVILLE SOUTH BOSTON
VICINITY TIL LATE EVENING...THEN SEEING A DRYING TREND. SKIES WILL
BE CLEARING SOMEWHAT OVER THE MIDDLE PART OF THE CWA WITH HIGH
CLOUDS THINNING OUT.
PREVIOUS VALID DISCUSSION...
IN THE WAKE OF THIS FRONT...HIGH PRESSURE BUILDS DOWN THE MID-
ATLANTIC REGION...ALLOWING SFC WINDS TO VEER TO THE
EAST/NORTHEAST. ABOVE THE SFC...850MB WINDS BACK TO THE SOUTH
HELPING TO PUSH LOW LEVEL MOISTURE/CLOUDS BACK INTO THE SOUTHERN
PORTION OF OUR FORECAST AREA AND KEEPING TEMPS ON THE WARM SIDE OF
GUIDANCE. MEANWHILE...ACROSS THE MOUNTAINS...AREAS OF CLEARING AND
DEW POINTS IN THE 30S WILL ALLOW LOWS TO FALL INTO THE MID-UPPER
30S. HOWEVER...NO FROST OR FREEZING CONDITIONS ARE EXPECTED FOR
AREAS IN AREAS WHERE THE GROWING SEASON HAS BEGUN.
DROPPED HIGHS SEVERAL DEGREES ON SATURDAY AS THE HIGH PRESSURE WEDGE
TAKES FIRM HOLD OVER OUR FORECAST AREA...KEEPING CLOUDS IN PLACE.
FORECAST MODELS ALSO INCREASE ISENTROPIC LIFT AT THE 295/300K SFCS
DURING THE AFTERNOON SATURDAY AND WOULD NOT BE SURPRISED TO SEE
AREAS OF LIGHT RAIN TO DEVELOP...ESPECIALLY SOUTH OF HIGHWAY
460...AS LOW LEVEL THETA-E RIDGE NOSES INTO THE REGION.
THEREFORE...INTRODUCED SMALL POPS FOR THIS AREA.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
AS OF 245 PM EDT FRIDAY...
AT 00Z SUNDAY A LOW WILL BE OFF THE COAST WITH A SURFACE HIGH OVER
THE CANADIAN MARITIMES PLACING THE REGION UNDER AN EASTERLY WEDGE
FLOW. GFS PREVIOUSLY HAD A SURFACE LOW RUNNING ACROSS THE OHIO
VALLEY SUNDAY BUT THE NEW 12Z RUN NOW HAS THE LOW UP ACROSS THE
GREAT LAKES. REGARDLESS...THERE WILL BE A TRAILING COLD FRONT THAT
WILL CROSS THE REGION DURING THE DAY MONDAY. ANOTHER PIECE OF ENERGY
WILL RIDE THE COAST AND WILL LIKELY ROB US SOMEWHAT FOR
RAINFALL...BUT STILL EXPECT THE REGION TO GET ABOUT A TENTH TO A
QUARTER INCH OF QPF. AFTER THE FRONTAL PASSAGE...HIGH PRESSURE WILL
BUILD IN BRINING DRIER CONDITIONS TO THE REGION.
EASTERLY FLOW WILL KEEP SURFACE TEMPS FAIRLY UNIFORM ACROSS THE
REGION ON SUNDAY WITH HIGHS IN THE LOW TO MID 60S. MONDAY WILL BRING
A COOL DOWN TO THE MOUNTAINS WITH HIGHS IN THE MID TO UPPER 50S BUT
A DOWNSLOPING FLOW SHOULD STILL KEEP AREAS EAST OF THE BLUE RIDGE IN
THE MID TO UPPER 60S ON MONDAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 245 PM EDT FRIDAY...
TUESDAY AND WEDNESDAY WILL BE DRY AND PLEASANT DAYS AS THE REGION
REMAINS UNDER THE INFLUENCE OF A SURFACE HIGH THAT WILL SLOWLY DRIFT
FROM SOUTHERN ONTARIO SOUTHEAST TO THE NEW ENGLAND STATES. MEANWHILE
A SURFACE LOW ACROSS THE NORTHERN PLAINS WILL BEGIN TO DEEPEN AS IT
MOVES E/NE INTO SOUTHERN CANADA. A COLD FRONT ASSOCIATED WITH THIS
SYSTEM WILL CROSS OUR AREA ON THURSDAY BRINGING SHOWERS AND POSSIBLY
THUNDERSTORMS. ON FRIDAY ADDITIONAL SHOWERS ARE POSSIBLE AS A
SURFACE LOW DEVELOPS ACROSS THE SOUTHEAST STATES AND SKIRTS JUST TO
OUR EAST BY FRIDAY EVENING. SURFACE TEMPS DURING THIS PERIOD WILL BE
NORMAL TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 100 AM EDT SATURDAY...
IR PICS AND OBS SHOW LOWER MVFR CIGS GRADUALLY SHIFTING BACK EAST
OUT OF WEST VA TONIGHT WITH ADDED VFR STRATO-CU DEVELOPING ALONG
THE SOUTHERN BLUE RIDGE. EXPECT THIS TREND TO CONTINUE WITH MVFR
CIGS LIKELY AT TIMES FROM THE BLUE RIDGE WEST OVERNIGHT...AND VFR
FROM KROA EAST IN A MIX OF STRATO-CU AND MID DECK THROUGH
DAYBREAK. HOWEVER COULD SEE CIGS LOWER ENOUGH FOR MORE WIDESPREAD
MVFR AROUND KDAN LATE AND PERHAPS IFR AROUND KBLF WHERE SOME VSBY
RESTRICTIONS IN FOG COULD ALSO DEVELOP.
FORECAST UNCERTAINTY CONTINUES IN REGARD TO CLOUD COVER DURING
SATURDAY WITH POTENTIAL FOR LOWER CIGS TO MIX OUT IN ALL EXCEPT
THE FAR WEST AND ACROSS THE SOUTH WHERE CLOSER TO A STALLED FRONT.
HOWEVER DEEPENING WEDGE DEVELOPMENT ALONG WITH MORE OF AN EASTERLY
TRAJECTORY LIKELY TO SWING LOW LEVEL MOISTURE NORTHWEST DURING
THE AFTERNOON WITH MVFR CIGS POSSIBLE BACK TO THE BLUE RIDGE.
THINK NORTHERN SECTIONS FROM KLWB TO KLYH HAVE THE BEST SHOT AT
SEEING MORE IN THE WAY OF VFR CIGS LONGER WHILE ELSEWHERE APPEARS
A PERIOD OF VFR BEFORE TRENDING TO HIGH END MVFR DURING THE
AFTERNOON FROM SE TO NW.
LATEST GUIDANCE SUGGESTS THAT LOW LEVEL MOISTURE WITHIN THE WEDGE COULD
SPREAD ACROSS THE ENTIRE REGION SATURDAY NIGHT RESULTING IN
WIDESPREAD SUB-VFR INCLUDING AREAS OF DRIZZLE/-RA FROM THE BLUE
RIDGE EAST BY SUNDAY MORNING. THIS WILL LIKELY CONTINUE
INTO EARLY SUNDAY AFTERNOON BEFORE POTENTIALLY SCATTERING OUT
FROM THE WEST AS THE WEDGE RETREATS NORTHEAST AHEAD OF THE NEXT
COLD FRONT.
EXTENDED DISCUSSION...
BY SUNDAY EVENING...AN UPPER TROUGH AND ASSOCIATED FRONTAL SYSTEM
WILL BE APPROACHING FROM THE WEST WITH MVFR-IFR CIGS/VSBYS LIKELY
OVERNIGHT IN RAIN SHOWERS FROM WEST TO EAST. BREEZY AND COOLER
CONDITIONS WILL FOLLOW FOR THE FIRST PART OF NEXT WEEK AS HIGH
PRESSURE BUILDS INTO THE REGION ALLOWING VFR CONDITIONS TO RETURN
BY MONDAY AFTERNOON. THE POSSIBLE DELAYED EXCEPTION WILL BE ACROSS
THE UPSLOPE AREAS OF WEST VA WHERE LOW CLOUDS AND MVFR CIGS COULD
LINGER INTO MONDAY AFTERNOON. VFR SHOULD THEN PREVAIL TUESDAY INTO
WEDNESDAY UNDER WEAK HIGH PRESSURE BEHIND THE FRONT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...CF/JH
NEAR TERM...PH/WP
SHORT TERM...CF
LONG TERM...CF
AVIATION...JH/PH/RAB
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1010 AM EDT SAT MAR 26 2016
.SYNOPSIS...
A WEAK COLD FRONT WILL STALL NEARBY TODAY...THEN LIFT NORTH AS A
WARM FRONT SUNDAY. A WEAK COLD FRONT WILL MOVE THROUGH THE AREA
MONDAY MORNING AND BE FOLLOWED BY A STRONGER REINFORCING COLD
FRONT MONDAY NIGHT. HIGH PRESSURE WILL BUILD IN FOR THE MIDDLE OF
NEXT WEEK BEFORE A STORM SYSTEM AFFECTS THE AREA LATE NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
MORNING UPDATE...CONTINUED TO ADJUST POPS AS THUNDERSTORMS MOVE
THROUGH COASTAL SOUTHEAST SOUTH CAROLINA. INCREASED QPF TO ACCOUNT
FOR HIGHER RAINFALL COVERAGE AND INCREASED CONFIDENCE THIS
MORNING. THE ONCE DISCRETE CELL CLUSTER IS SHOWING SIGNS OF
BECOMING MORE ORGANIZED WHILE MOVING THROUGH THE CHARLESTON TRI-
COUNTY AREA. SMALL HAIL AND WIND GUSTS UP TO 50 MPH ARE POSSIBLE
IN THE STRONGEST STORMS THIS MORNING.
ALSO...SOME CLEARING FOR SOUTHEAST GEORGIA IS BEING NOTED ON
VISIBLE SAT IMAGERY AND SURFACE OBS. WHILE BRIEF PERIODS OF SUN
COULD FILTER THROUGH THIS MORNING IT IS NOT EXPECTED TO HAVE ANY
SUBSTANTIAL IMPACT ON TEMPS OR INSTABILITY.
PREVIOUS DISCUSSION...A COLD FRONT WILL STALL OVER THE SOUTHERN
MIDLANDS AND CSRA TODAY. A WARM AND MOIST AIRMASS WILL REMAIN IN
PLACE ACROSS THE REGION WITH PWATS FORECAST TO SURGE TO 1.5-1.75
INCHES. A NUMBER OF UPSTREAM IMPULSES EMBEDDED WITHIN THE
SUBTROPICAL JET WILL TRAVERSE THE SOUTHEAST U.S. TODAY...THE
STRONGEST OF WHICH WILL PASS ACROSS SOUTHEAST GEORGIA EARLY THIS
AFTERNOON. UPPER FORCING WITH THIS FEATURE COUPLED WITH A WELL-
DEFINED 250 HPA DIFLUENCE SIGNATURE AND STRONG ISENTROPIC ASSENT
NOTED ALONG THE NOSE OF 35 KT LOW- LEVEL JET WILL SUPPORT A STEADY
UPTICK IN CONVECTION AFTER SUNRISE WHICH WILL GRADUALLY FILL IN
AND IMPACT MUCH OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA
THROUGH THE DAY.
THERE ARE SIGNALS THAT SOME SORT OF CONVECTIVE CLUSTER COULD MOVE
ACROSS NORTHERN FLORIDA AND FAR SOUTHEAST GEORGIA LATER THIS
MORNING. SHOULD THIS FEATURE DEVELOP...IT COULD DISRUPT THE INFLOW
OF MOISTURE INTO SOUTHERN SOUTH CAROLINA AND THUS LIMIT THE
COVERAGE OF SHOWERS AND TSTMS. THE POP FORECAST WILL REMAIN FAIRLY
CONSERVATIVE FOR THIS REASON...RANGING FROM 70 PERCENT FOR MUCH OF
SOUTHERN SOUTH CAROLINA TO 80 PERCENT ACROSS SOUTHEAST GEORGIA.
HIGHS WILL ONLY WARM INTO THE MID 70S FOR MOST AREAS TODAY DUE TO
EXTENSIVE CLOUD COVER AND DEVELOPING SHOWERS/TSTMS. COULD SEE AN
AREA OF ENHANCED INSTABILITY DEVELOP IN THE SAVANNAH- DARIEN-
LUDOWICI CORRIDOR WHERE MODIFIED RAP SOUNDINGS SHOW SBCAPES
NEARING 1200 J/KG WITH LIFTED INDICES -4 TO -6C. GIVEN THE AMOUNT
OF 0-6KM BULK SHEAR THAT IS PLACE AND THE PRESENCE OF A MODEST
LOW-LEVEL JET...AN ISOLATED STRONG TO PERHAPS SEVERE TSTM CAN NOT
BE RULED OUT IN THIS AREA.
TONIGHT...THE RISK FOR ISOLATED TO SCATTERED SHOWERS WILL LINGER
THE NIGHT AS THE AREA REMAINS FULLY EMBEDDED WITHIN THE WARM
SECTOR AND A POWERFUL SUBTROPICAL JET REMAINS IN PLACE ALOFT. MORE
CONCENTRATED ACTIVITY WILL BEING TO IMPACT INTERIOR SOUTHEAST
GEORGIA CLOSER TO DAYBREAK SUNDAY AS YET ANOTHER SHORTWAVE
EMBEDDED WITHIN THE SUBTROPICAL JET APPROACHES. LOWS WILL RANGE
FROM THE LOWER TO MID 60S...WARMEST SOUTH OF THE I-16 CORRIDOR.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/... TONIGHT...THE RISK FOR
ISOLATED TO SCATTERED SHOWERS WILL LINGER THE NIGHT AS THE AREA
REMAINS FULLY EMBEDDED WITHIN THE WARM SECTOR AND A POWERFUL
SUBTROPICAL JET REMAINS IN PLACE ALOFT. MORE CONCENTRATED ACTIVITY
WILL BEING TO IMPACT INTERIOR SOUTHEAST GEORGIA CLOSER TO DAYBREAK
SUNDAY AS YET ANOTHER SHORTWAVE EMBEDDED WITHIN THE SUBTROPICAL
JET APPROACHES. LOWS WILL RANGE FROM THE LOWER TO MID
60S...WARMEST SOUTH OF THE I-16 CORRIDOR.
SUNDAY AND SUNDAY NIGHT... A BACKDOOR COLD FRONT WILL PUSH SOUTHWARD
INTO THE CAROLINAS EARLY SUNDAY MORNING AS HIGH PRESSURE BUILDS OVER
NEW ENGLAND. AS THE HIGH MOVES OFF OF THE NEW ENGLAND COAST DURING
THE DAY THE FRONT WILL TRANSITION INTO A WARM FRONT AND THEN LIFT
NORTHWARD INTO THE MID-ATLANTIC STATES. WARM AIR ADVECTION WILL
INCREASE THROUGH THE DAY. NAEFS SHOWS HIGHEST ATMOSPHERIC MOISTURE
CONTENT THROUGH THIS PERIOD WITH P-WATS 2 TO 3 STANDARD DEVIATIONS
ABOVE NORMAL STREAMING INTO THE AREA ON THE BACK OF DEEP LAYER
SOUTHWESTERLY FLOW.
A SHORTWAVE ALOFT MOVING ACROSS THE SOUTHEAST WILL PASS NEAR OR OVER
THE AREA SUNDAY AFTERNOON OR EVENING. AS THIS BAROCLINIC ZONE
APPROACHES THE AREA MAINLY DYNAMICALLY DRIVEN PRECIP WILL ENSUE.
GIVEN THE HIGH MOISTURE VALUES AND PVA ALOFT AT LEAST NUISANCE
FLOODING IS POSSIBLE...WITH WIDESPREAD FLOODING NOT EXPECTED.
OVERALL LACK OF INSTABILITY WILL GREATLY LIMIT THE SEVERE THREAT.
POPS CONTINUE SUNDAY NIGHT AS THE SHORTWAVE CROSSES THE AREA.
THICK CLOUD COVER WILL PROVIDE AMPLE INSULATION AND TEMPS WILL ONLY
FALL ABOUT 10F FROM THE DAYTIME HIGHS. SOME STRATUS BUILD DOWN IS
POSSIBLE BETWEEN SHOWERS GIVEN THE AMPLE MOISTURE IN THE LOW
LEVELS...BUT CONFIDENCE IN VISIBILITY REDUCTIONS IS STILL TOO LOW TO
INCLUDE IN THE OFFICIAL FORECAST AT THIS POINT.
MONDAY...AN INITIAL WEAK COLD FRONT WILL CROSS THE AREA AROUND
SUNRISE MONDAY...BRINGING WESTERLY FLOW DURING THE DAY. THIS WILL
LEAD TO THE WARMEST TEMPS OF THE PERIOD WITH HIGHS NEAR 80 FOR MOST.
KEPT SLIGHT CHANCE POPS IN THE FORECAST THROUGH THE DAY AS MOISTURE
CONTENT REMAINS SOMEWHAT ELEVATED IN THE LOW LEVELS.
ZONAL FLOW ALOFT OR POSSIBLY WEAK RIDGING WILL FILL IN AND THE UPPER
LEVELS WILL DRY OUT KEEPING ANY SHOWER ACTIVITY ISOLATED IN NATURE
AND PRECLUDING ANY SEVERE THREAT. DRIER CONDITIONS ARE EXPECTED
DURING THE EVENING AND OVERNIGHT AS SURFACE HIGH PRESSURE BUILDS
ACROSS THE EASTERN HALF OF THE U.S. LOW TEMPERATURES WILL BE
SLIGHTLY ABOVE NORMAL.
TUESDAY...SURFACE HIGH PRESSURE CENTERED OVER THE GREAT LAKES WILL
STRETCH DOWN INTO THE CAROLINAS WHILE A RIDGE WILL BE MOVING OVER
THE MISSISSIPPI VALLEY. NORTHEAST WINDS AT THE SURFACE COMBINED WITH
NORTHWEST WINDS ALOFT WILL USHER IN COOLER TEMPERATURES TO OUR
REGION. DESPITE PLENTY OF SUN...HIGH TEMPERATURES MAY BE SLIGHTLY
BELOW NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
DRY HIGH PRESSURE WILL BUILD INTO THE AREA TUESDAY NIGHT AND
WEDNESDAY. TEMPERATURES WILL BE NEAR NORMAL. A WARMING TREND IS
EXPECTED THURSDAY AS THE HIGH MOVES OFFSHORE. A LOW PRESSURE SYSTEM
WILL APPROACH THE SOUTHEASTERN U.S. BY THURSDAY...BRINGING OUR AREA
THE THREAT OF RAIN INTO FRIDAY.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
THUNDERSTORM ACTIVITY WILL CONTINUE AT KCHS THROUGH MID-LATE
MORNING. THERE REMAINS TIMING/COVERAGE ISSUES IN THE VARIOUS HIGH
RESOLUTION DATA SETS...WHICH LEADS TO ONLY AVERAGE CONFIDENCE ON
IMPACTS AT THE TERMINALS. LOOKS LIKE THE GREATEST IMPACT WINDOW
FOR SHOWERS/TSTMS AT KSAV WILL BE ROUGHLY 16-19Z AND 18-21Z A
KCHS. WILL CARRY TEMPO GROUPS FOR LOW-END MVFR CONDITIONS DURING
THIS TIME. MOST THE RAIN IS EXPECTED TO CLEAR KSAV BY MID
AFTERNOON AND LATE AFTERNOON AT KCHS. LOW STRATUS COULD DEVELOP
OVERNIGHT AS A WARM/MOIST AIRMASS REMAINS IN PLACE WITH WET
GROUNDS. BEST CHANCES FOR IFR OR LOWER WILL BE AT KSAV. WILL LIMIT
CIGS TO LOW-END MVFR FOR NOW.
EXTENDED AVIATION OUTLOOK...PERIODS OF FLIGHT RESTRICTIONS ARE
EXPECTED SUNDAY THROUGH MONDAY MORNING DUE TO A FRONT STALLING OVER
OR NEAR THE AREA.
&&
.MARINE...
TODAY...LIGHT WINDS THIS MORNING WILL BECOME SOUTH AND INCREASE TO
NEAR 10 KT LATER THIS MORNING. SEAS WILL AVERAGE 2-4 FT. SOME
THUNDERSTORMS WILL CONTAIN FREQUENT CLOUD TO CLOUD AND CLOUD TO
GROUND LIGHTNING.
TONIGHT...A LIGHT...SOUTHERLY WIND REGIME WILL HOLD THROUGH THE
NIGHT AS A STATIONARY FRONT REMAINS TO THE THE WEST. SEAS WILL
AVERAGE 2-4 FT.
SUNDAY THROUGH WEDNESDAY...SUNDAY A WARM FRONT WILL LIFT NORTHWARD...
CAUSING INCREASED SOUTHWESTERLY WINDS. CONDITIONS WILL IMPROVE
MONDAY AS A COLD FRONT APPROACHES AND THEN MOVES THROUGH THE
REGION. HIGH PRESSURE WILL THEN PASS TO OUR NORTH THROUGH THE
MIDDLE OF NEXT WEEK.
RIP CURRENTS...LATEST OBSERVATIONS AND OUTPUT FROM NWPS INDICATES
1-2 FT SWELLS OF 8-9 SECONDS WILL IMPACT THE BEACHES TODAY.
DESPITE THIS AND SOME LINGERING ASTRONOMICAL INFLUENCES... FAIRLY
LIGHT WINDS OF 10 KT OR LESS WILL LIMIT THE OVERALL RIP CURRENT
RISK. A LOW RISK WILL BE INDICATED FOR ALL BEACHES THROUGH SUNSET.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...CEB/ST
SHORT TERM...MS
LONG TERM...MS
AVIATION...CEB/MS
MARINE...CEB/MS
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
658 AM EDT SAT MAR 26 2016
.SYNOPSIS...
A WEAK COLD FRONT WILL STALL NEARBY TODAY...THEN LIFT NORTH AS A
WARM FRONT SUNDAY. A WEAK COLD FRONT WILL MOVE THROUGH THE AREA
MONDAY MORNING AND BE FOLLOWED BY A STRONGER REINFORCING COLD
FRONT MONDAY NIGHT. HIGH PRESSURE WILL BUILD IN FOR THE MIDDLE OF
NEXT WEEK BEFORE A STORM SYSTEM AFFECTS THE AREA LATE NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A COLD FRONT WILL STALL OVER THE SOUTHERN MIDLANDS AND CSRA TODAY.
A WARM AND MOIST AIRMASS WILL REMAIN IN PLACE ACROSS THE REGION
WITH PWATS FORECAST TO SURGE TO 1.5-1.75 INCHES. A NUMBER OF
UPSTREAM IMPULSES EMBEDDED WITHIN THE SUBTROPICAL JET WILL
TRAVERSE THE SOUTHEAST U.S. TODAY...THE STRONGEST OF WHICH WILL
PASS ACROSS SOUTHEAST GEORGIA EARLY THIS AFTERNOON. UPPER FORCING
WITH THIS FEATURE COUPLED WITH A WELL-DEFINED 250 HPA DIFLUENCE
SIGNATURE AND STRONG ISENTROPIC ASSENT NOTED ALONG THE NOSE OF 35
KT LOW- LEVEL JET WILL SUPPORT A STEADY UPTICK IN CONVECTION AFTER
SUNRISE WHICH WILL GRADUALLY FILL IN AND IMPACT MUCH OF SOUTHEAST
SOUTH CAROLINA AND SOUTHEAST GEORGIA THROUGH THE DAY.
THERE ARE SIGNALS THAT SOME SORT OF CONVECTIVE CLUSTER COULD MOVE
ACROSS NORTHERN FLORDIA AND FAR SOUTHEAST GEORGIA LATER THIS
MORNING. SHOULD THIS FEATURE DEVELOP...IT COULD DISRUPT THE INFLOW
OF MOISTURE INTO SOUTHERN SOUTH CAROLINA AND THUS LIMIT THE
COVERAGE OF SHOWERS AND TSTMS. THE POP FORECAST WILL REMAIN FAIRLY
CONSERVATIVE FOR THIS REASON...RANGING FROM 70 PERCENT FOR MUCH OF
SOUTHERN SOUTH CAROLINA TO 80 PERCENT ACROSS SOUTHEAST GEORGIA.
HIGHS WILL ONLY WARM INTO THE MID 70S FOR MOST AREAS TODAY DUE TO
EXTENSIVE CLOUD COVER AND DEVELOPING SHOWERS/TSTMS. COULD SEE AN
AREA OF ENHANCED INSTABILITY DEVELOP IN THE SAVANNAH- DARIEN-
LUDOWICI CORRIDOR WHERE MODIFIED RAP SOUNDINGS SHOW SBCAPES
NEARING 1200 J/KG WITH LIFTED INDICES -4 TO -6C. GIVEN THE AMOUNT
OF 0-6KM BULK SHEAR THAT IS PLACE AND THE PRESENCE OF A MODEST
LOW-LEVEL JET...AN ISOLATED STRONG TO PERHAPS SEVERE TSTM CAN NOT
BE RULED OUT IN THIS AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
TONIGHT...THE RISK FOR ISOLATED TO SCATTERED SHOWERS WILL LINGER
THE NIGHT AS THE AREA REMAINS FULLY EMBEDDED WITHIN THE WARM
SECTOR AND A POWERFUL SUBTROPICAL JET REMAINS IN PLACE ALOFT. MORE
CONCENTRATED ACTIVITY WILL BEING TO IMPACT INTERIOR SOUTHEAST
GEORGIA CLOSER TO DAYBREAK SUNDAY AS YET ANOTHER SHORTWAVE
EMBEDDED WITHIN THE SUBTROPICAL JET APPROACHES. LOWS WILL RANGE
FROM THE LOWER TO MID 60S...WARMEST SOUTH OF THE I-16 CORRIDOR.
SUNDAY AND SUNDAY NIGHT... A BACKDOOR COLD FRONT WILL PUSH SOUTHWARD
INTO THE CAROLINAS EARLY SUNDAY MORNING AS HIGH PRESSURE BUILDS OVER
NEW ENGLAND. AS THE HIGH MOVES OFF OF THE NEW ENGLAND COAST DURING
THE DAY THE FRONT WILL TRANSITION INTO A WARM FRONT AND THEN LIFT
NORTHWARD INTO THE MID-ATLANTIC STATES. WARM AIR ADVECTION WILL
INCREASE THROUGH THE DAY. NAEFS SHOWS HIGHEST ATMOSPHERIC MOISTURE
CONTENT THROUGH THIS PERIOD WITH P-WATS 2 TO 3 STANDARD DEVIATIONS
ABOVE NORMAL STREAMING INTO THE AREA ON THE BACK OF DEEP LAYER
SOUTHWESTERLY FLOW.
A SHORTWAVE ALOFT MOVING ACROSS THE SOUTHEAST WILL PASS NEAR OR OVER
THE AREA SUNDAY AFTERNOON OR EVENING. AS THIS BAROCLINIC ZONE
APPROACHES THE AREA MAINLY DYNAMICALLY DRIVEN PRECIP WILL ENSUE.
GIVEN THE HIGH MOISTURE VALUES AND PVA ALOFT AT LEAST NUISANCE
FLOODING IS POSSIBLE...WITH WIDESPREAD FLOODING NOT EXPECTED.
OVERALL LACK OF INSTABILITY WILL GREATLY LIMIT THE SEVERE THREAT.
POPS CONTINUE SUNDAY NIGHT AS THE SHORTWAVE CROSSES THE AREA.
THICK CLOUD COVER WILL PROVIDE AMPLE INSULATION AND TEMPS WILL ONLY
FALL ABOUT 10F FROM THE DAYTIME HIGHS. SOME STRATUS BUILD DOWN IS
POSSIBLE BETWEEN SHOWERS GIVEN THE AMPLE MOISTURE IN THE LOW
LEVELS...BUT CONFIDENCE IN VISIBILITY REDUCTIONS IS STILL TOO LOW TO
INCLUDE IN THE OFFICIAL FORECAST AT THIS POINT.
MONDAY...AN INITIAL WEAK COLD FRONT WILL CROSS THE AREA AROUND
SUNRISE MONDAY...BRINGING WESTERLY FLOW DURING THE DAY. THIS WILL
LEAD TO THE WARMEST TEMPS OF THE PERIOD WITH HIGHS NEAR 80 FOR MOST.
KEPT SLIGHT CHANCE POPS IN THE FORECAST THROUGH THE DAY AS MOISTURE
CONTENT REMAINS SOMEWHAT ELEVATED IN THE LOW LEVELS.
ZONAL FLOW ALOFT OR POSSIBLY WEAK RIDGING WILL FILL IN AND THE UPPER
LEVELS WILL DRY OUT KEEPING ANY SHOWER ACTIVITY ISOLATED IN NATURE
AND PRECLUDING ANY SEVERE THREAT. DRIER CONDITIONS ARE EXPECTED
DURING THE EVENING AND OVERNIGHT AS SURFACE HIGH PRESSURE BUILDS
ACROSS THE EASTERN HALF OF THE U.S. LOW TEMPERATURES WILL BE
SLIGHTLY ABOVE NORMAL.
TUESDAY...SURFACE HIGH PRESSURE CENTERED OVER THE GREAT LAKES WILL
STRETCH DOWN INTO THE CAROLINAS WHILE A RIDGE WILL BE MOVING OVER
THE MISSISSIPPI VALLEY. NORTHEAST WINDS AT THE SURFACE COMBINED WITH
NORTHWEST WINDS ALOFT WILL USHER IN COOLER TEMPERATURES TO OUR
REGION. DESPITE PLENTY OF SUN...HIGH TEMPERATURES MAY BE SLIGHTLY
BELOW NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
DRY HIGH PRESSURE WILL BUILD INTO THE AREA TUESDAY NIGHT AND
WEDNESDAY. TEMPERATURES WILL BE NEAR NORMAL. A WARMING TREND IS
EXPECTED THURSDAY AS THE HIGH MOVES OFFSHORE. A LOW PRESSURE SYSTEM
WILL APPROACH THE SOUTHEASTERN U.S. BY THURSDAY...BRINGING OUR AREA
THE THREAT OF RAIN INTO FRIDAY.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
INITIAL SHOWER/TSTM ACTIVITY HAS PASSED BOTH TERMINALS...BUT LOOK
FOR ADDITIONAL REDEVELOP TO OCCUR OVER SOUTHEAST GEORGIA BY MID-
LATE MORNING...THEN SPREADING NORTHEAST INTO SOUTHERN SOUTH
CAROLINA. THERE REMAINS TIMING/COVERAGE ISSUES IN THE VARIOUS HIGH
RESOLUTION DATA SETS...WHICH LEADS TO ONLY AVERAGE CONFIDENCE ON
IMPACTS AT THE TERMINALS. LOOKS LIKE THE GREATEST IMPACT WINDOW
FOR SHOWERS/TSTMS AT KSAV WILL BE ROUGHLY 16-19Z AND 18-21Z A
KCHS. WILL CARRY TEMPO GROUPS FOR LOW-END MVFR CONDITIONS DURING
THIS TIME. MOST THE RAIN IS EXPECTED TO CLEAR KSAV BY MID
AFTERNOON AND LATE AFTERNOON AT KCHS. LOW STRATUS COULD DEVELOP
OVERNIGHT AS A WARM/MOIST AIRMASS REMAINS IN PLACE WITH WET
GROUNDS. BEST CHANCES FOR IFR OR LOWER WILL BE AT KSAV. WILL LIMIT
CIGS TO LOW-END MVFR FOR NOW.
EXTENDED AVIATION OUTLOOK...PERIODS OF FLIGHT RESTRICTIONS ARE
EXPECTED SUNDAY THROUGH MONDAY MORNING DUE TO A FRONT STALLING OVER
OR NEAR THE AREA.
&&
.MARINE...
TODAY...LIGHT WINDS THIS MORNING WILL BECOME SOUTH AND INCREASE TO
NEAR 10 KT LATER THIS MORNING. SEAS WILL AVERAGE 2-4 FT.
TONIGHT...A LIGHT...SOUTHERLY WIND REGIME WILL HOLD THROUGH THE
NIGHT AS A STATIONARY FRONT REMAINS TO THE THE WEST. SEAS WILL
AVERAGE 2-4 FT.
SUNDAY THROUGH WEDNESDAY...SUNDAY A WARM FRONT WILL LIFT NORTHWARD...
CAUSING INCREASED SOUTHWESTERLY WINDS. CONDITIONS WILL IMPROVE
MONDAY AS A COLD FRONT APPROACHES AND THEN MOVES THROUGH THE
REGION. HIGH PRESSURE WILL THEN PASS TO OUR NORTH THROUGH THE
MIDDLE OF NEXT WEEK.
RIP CURRENTS...LATEST OBSERVATIONS AND OUTPUT FROM NWPS INDICATES
1-2 FT SWELLS OF 8-9 SECONDS WILL IMPACT THE BEACHES TODAY.
DESPITE THIS AND SOME LINGERING ASTRONOMICAL INFLUENCES... FAIRLY
LIGHT WINDS OF 10 KT OR LESS WILL LIMIT THE OVERALL RIP CURRENT
RISK. A LOW RISK WILL BE INDICATED FOR ALL BEACHES THROUGH SUNSET.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
626 AM EDT SAT MAR 26 2016
.SYNOPSIS...
A COLD FRONT WILL STALL ACROSS THE AREA TODAY THEN RETREAT
NORTHWARD AS A WARM FRONT SUNDAY. THIS WILL RESULT IN SCATTERED TO
NUMEROUS SHOWERS ACROSS THE REGION TODAY AND SUNDAY. A FEW
THUNDERSTORMS ARE POSSIBLE. ANOTHER COLD FRONT WILL MOVE ACROSS
THE REGION MONDAY. TEMPERATURES AT OR SLIGHTLY BELOW NORMAL
THROUGH THE WEEKEND. HIGH PRESSURE WILL OVERSPREAD THE REGION
TUESDAY AND WEDNESDAY. ANOTHER CHANCE FOR RAIN WILL REENTER THE
REGION BY THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
DENSE FOG HAS BECOME MORE WIDESPREAD ACROSS THE NORTHERN MIDLANDS
AND THE PIEDMONT. THE FOG DEVELOPED IN JUST AHEAD OF BACKDOOR COLD
FRONT LOCATED JUST NORTH OF THE BORDER. THE FOG SHOULD BEGIN TO
DISSIPATE AFTER SUNRISE AS THE COLD FRONT MAKES ITS WAY INTO THE
MIDLANDS. THE FRONT IS FORECAST TO STALL OVER MIDLANDS LATER
TODAY.
GOOD AGREEMENT AMONG THE HIGH RESOLUTION AND NEAR TERM MODELS IN
SHOWING AN INCREASE IN SHOWERS THIS MORNING AS A WEAK SHORTWAVE
LIFTS NORTHEASTWARD INTO THE AREA AND INTERACTS WITH THE FRONTAL
BOUNDARY. CONSENSUS GUIDANCE POPS INDICATED LIKELY TO CATEGORICAL
POPS. A WEAK SHALLOW WEDGE IS FORECAST TO DEVELOP ACROSS THE
NORTHERN MIDLANDS WITH NORTHEAST LOW LEVEL FLOW. DEEPER MOISTURE
AND GREATER INSTABILITY FORECAST ACROSS THE SOUTHERN MIDLANDS AND
CSRA WILL LEAD TO THE CHANCE FOR A FEW THUNDERSTORMS.
THE COMBINATION OF CLOUDS...THE SHALLOW WEDGE AND SHOWERS WILL
SHOULD HOLD TEMPERATURES IN THE 60S ACROSS THE NORTH MIDLANDS WITH
WARMER READINGS IN THE LOWER 70S ACROSS THE SOUTHERN MIDLANDS AND
CSRA. COULD SEE SHOWERS DECREASE TONIGHT AS INSTABILITY DECREASES
AND SHORT WAVE ENERGY LIFTS OUT OF THE FORECAST AREA. KEPT
OVERNIGHT LOWS NEAR GUIDANCE CONSENSUS...IN THE MID 50S NORTH TO
LOWER 60S SOUTH.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
THE STALLED FRONTAL BOUNDARY IS FORECAST TO LIFT NORTH OF THE
MIDLANDS AS A WARM FRONT SUNDAY. INCREASING MOISTURE AND
INSTABILITY SOUTH OF THE BOUNDARY WILL HOLD THE THREAT OF
SHOWERS AND THUNDERSTORMS ACROSS THE AREA SUNDAY. GUIDANCE
CONSENSUS CONTINUE TO INDICATE CATEGORICAL POPS. QPF AROUND 1 TO
2 INCHES POSSIBLE MAINLY IN THE SOUTHEAST MIDLANDS/CSRA.
GUIDANCE IN GOOD AGREEMENT WITH HIGHS IN THE UPPER 60S TO MID 70S
ON SUNDAY.
BROAD UPPER LEVEL TROUGH MOVING EAST ACROSS THE TENNESSEE AND
OHIO VALLEY SUNDAY NIGHT WILL DRIVE ANOTHER COLD FRONT THROUGH THE
REGION MONDAY AFTERNOON. EXPECT MOST SHOWERS TO MOVE EAST OF THE
AREA EARLY MONDAY SO DECREASING POPS DURING THE DAY WITH CLEARING
BY AFTERNOON AS MOISTURE BECOMES SHALLOW AND DEVELOPMENT OF MID
LEVEL CAP. GUIDANCE GIVES HIGH TEMPERATURES AROUND 80S WITH DRYING
AND DOWNSLOPE FLOW DEVELOPING.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER LEVEL RIDGE IS FORECAST TO BUILD FROM THE CENTRAL CONUS TO
THE EAST COAST TUESDAY THROUGH WEDNESDAY...MOVING OFF THE OFF THE
COAST THURSDAY. THIS SHOULD HELP TO BRING A PERIOD OF DRY WEATHER
BACK TO THE AREA THROUGH MID-WEEK. PRECIP REENTERS THE FORECAST
ONCE AGAIN THURSDAY INTO FRIDAY AHEAD OF THE NEXT SYSTEM. GUIDANCE
BLEND POPS INCREASING SO RAISED POPS LATE WEEK. TEMPERATURES ARE
EXPECTED TO BE NEAR NORMAL.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
IFR CONDITIONS...WITH PERIODS OF MVFR...EXPECTED TO DOMINATE THE
PERIOD.
REGIONAL RADAR SHOWING SHOWER ACTIVITY MOVING THROUGH THE CSRA AND
INTO THE CENTRAL MIDLANDS THIS MORNING. ACTIVITY WILL CONTINUE
THROUGH THE MORNING. HRRR CONTINUES TO SHOW SEVERAL WAVES OF
SHOWERS MOVING THROUGH THE REGION THROUGHOUT THE DAY. CAN NOT RULE
OUT THUNDER WITH THE HEAVIER ACTIVITY...BUT CONFIDENCE NOT HIGH
ENOUGH TO PUT IN TAFS AT THIS TIME.
OVERCAST SKIES WITH CEILINGS LESS THAN 1 KFT ACROSS MUCH OF THE
REGION...AND MOST MODELS CONTINUE THESE CONDITIONS THROUGH THE
PERIOD. VISIBILITIES MAY BE QUITE VARIABLE THROUGH THE
DAY...DEPENDING ON WHETHER TAF SITE IS BEING IMPACTED BY SHOWER
ACTIVITY OR NOT. HAVE GENERALLY KEPT VISIBILITIES IN THE MVFR
CATEGORY.
WINDS THROUGH THE PERIOD WILL BE SOUTHWESTERLY THROUGH THE EARLY
MORNING HOURS...THEN BACK TO EASTERLY FOR THE REMAINDER OF THE
PERIOD WITH SPEEDS OF 6 KNOTS OR LESS.
EXTENDED AVIATION OUTLOOK...INCREASING CONFIDENCE IN IFR
CONDITIONS PRE-DAWN SUNDAY THROUGH MONDAY MORNING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...DENSE FOG ADVISORY UNTIL 8 AM EDT THIS MORNING FOR SCZ015-016-
020>022.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
552 AM EDT SAT MAR 26 2016
.SYNOPSIS...
A COLD FRONT WILL STALL ACROSS THE AREA TODAY THEN RETREAT
NORTHWARD AS A WARM FRONT SUNDAY. THIS WILL RESULT IN SCATTERED TO
NUMEROUS SHOWERS ACROSS THE REGION TODAY AND SUNDAY. A FEW
THUNDERSTORMS ARE POSSIBLE. ANOTHER COLD FRONT WILL MOVE ACROSS
THE REGION MONDAY. TEMPERATURES AT OR SLIGHTLY BELOW NORMAL
THROUGH THE WEEKEND. HIGH PRESSURE WILL OVERSPREAD THE REGION
TUESDAY AND WEDNESDAY. ANOTHER CHANCE FOR RAIN WILL REENTER THE
REGION BY THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
DENSE FOG HAS BECOME MORE WIDESPREAD ACROSS THE NORTHERN MIDLANDS
AND THE PIEDMONT. THE FOG DEVELOPED IN JUST AHEAD OF BACKDOOR COLD
FRONT LOCATED JUST NORTH OF THE BORDER. THE FOG SHOULD BEGIN TO
DISSIPATE AFTER SUNRISE AS THE COLD FRONT MAKES ITS WAY INTO THE
MIDLANDS. THE FRONT IS FORECAST TO STALL OVER MIDLANDS LATER
TODAY.
GOOD AGREEMENT AMONG THE HIGH RESOLUTION AND NEAR TERM MODELS IN
SHOWING AN INCREASE IN SHOWERS THIS MORNING AS A WEAK SHORTWAVE
LIFTS NORTHEASTWARD INTO THE AREA AND INTERACTS WITH THE FRONTAL
BOUNDARY. CONSENSUS GUIDANCE POPS INDICATED LIKELY TO CATEGORICAL
POPS. A WEAK SHALLOW WEDGE IS FORECAST TO DEVELOP ACROSS THE
NORTHERN MIDLANDS WITH NORTHEAST LOW LEVEL FLOW. DEEPER MOISTURE
AND GREATER INSTABILITY FORECAST ACROSS THE SOUTHERN MIDLANDS AND
CSRA WILL LEAD TO THE CHANCE FOR A FEW THUNDERSTORMS.
THE COMBINATION OF CLOUDS...THE SHALLOW WEDGE AND SHOWERS WILL
SHOULD HOLD TEMPERATURES IN THE 60S ACROSS THE NORTH MIDLANDS WITH
WARMER READINGS IN THE LOWER 70S ACROSS THE SOUTHERN MIDLANDS AND
CSRA. COULD SEE SHOWERS DECREASE TONIGHT AS INSTABILITY DECREASES
AND SHORT WAVE ENERGY LIFTS OUT OF THE FORECAST AREA. KEPT
OVERNIGHT LOWS NEAR GUIDANCE CONSENSUS...IN THE MID 50S NORTH TO
LOWER 60S SOUTH.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
THE STALLED FRONTAL BOUNDARY IS FORECAST TO LIFT NORTH OF THE
MIDLANDS AS A WARM FRONT SUNDAY. INCREASING MOISTURE AND
INSTABILITY SOUTH OF THE BOUNDARY WILL HOLD THE THREAT OF
SHOWERS AND THUNDERSTORMS ACROSS THE AREA SUNDAY. GUIDANCE
CONSENSUS CONTINUE TO INDICATE CATEGORICAL POPS. QPF AROUND 1 TO
2 INCHES POSSIBLE MAINLY IN THE SOUTHEAST MIDLANDS/CSRA.
GUIDANCE IN GOOD AGREEMENT WITH HIGHS IN THE UPPER 60S TO MID 70S
ON SUNDAY.
BROAD UPPER LEVEL TROUGH MOVING EAST ACROSS THE TENNESSEE AND
OHIO VALLEY SUNDAY NIGHT WILL DRIVE ANOTHER COLD FRONT THROUGH THE
REGION MONDAY AFTERNOON. EXPECT MOST SHOWERS TO MOVE EAST OF THE
AREA EARLY MONDAY SO DECREASING POPS DURING THE DAY WITH CLEARING
BY AFTERNOON AS MOISTURE BECOMES SHALLOW AND DEVELOPMENT OF MID
LEVEL CAP. GUIDANCE GIVES HIGH TEMPERATURES AROUND 80S WITH DRYING
AND DOWNSLOPE FLOW DEVELOPING.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER LEVEL RIDGE IS FORECAST TO BUILD FROM THE CENTRAL CONUS TO
THE EAST COAST TUESDAY THROUGH WEDNESDAY...MOVING OFF THE OFF THE
COAST THURSDAY. THIS SHOULD HELP TO BRING A PERIOD OF DRY WEATHER
BACK TO THE AREA THROUGH MID-WEEK. PRECIP REENTERS THE FORECAST
ONCE AGAIN THURSDAY INTO FRIDAY AHEAD OF THE NEXT SYSTEM. GUIDANCE
BLEND POPS INCREASING SO RAISED POPS LATE WEEK. TEMPERATURES ARE
EXPECTED TO BE NEAR NORMAL.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
MVFR TO IFR CONDITIONS EXPECTED TO DOMINATE THE PERIOD.
SURFACE OBS INDICATE AREAS OF LOW CLOUDS CONTINUE TO DEVELOP
ACROSS THE MIDLANDS AND CSRA...WITH MANY SITES BEGINNING TO DROP
BELOW 1 KFT. EXPECT THE LOW CLOUDS TO CONTINUE DEVELOPING OVER
THE NEXT COUPLE OF HOURS. MOST SITES IFR ALREADY...WITH OGB THE
EXCEPTION. OGB WILL DROP INTO MVFR AS LOWER CLOUDS DEVELOP ACROSS
THE SOUTHEASTERN MIDLANDS.
BY SUNRISE A PUSH OF GULF MOISTURE WILL BE MOVING NORTHWARD ALONG
THE FRONT AND BRING SHOWERS TO THE AREA. HRRR SHOWS THAT THE HIGHEST
CHANCE OF SHOWERS AT AGS/DNL/OGB SHOULD OCCUR FROM LATE MORNING
THROUGH THE END OF THE PERIOD...WITH SIMILAR CONDITIONS BEGINNING
AT CAE/CUB AN HOUR OR SO LATER. THUNDERSTORMS WILL BE POSSIBLE
FROM 16Z ONWARD...HOWEVER THE POTENTIAL FOR CONVECTION REMAINS TOO
LOW TO INCLUDE ATTM. WINDS THROUGH THE PERIOD WILL BE SOUTHWESTERLY
THROUGH THE EARLY MORNING HOURS...THEN BACK TO EASTERLY FOR THE
REMAINDER OF THE PERIOD WITH SPEEDS OF 6 KNOTS OR LESS.
EXTENDED AVIATION OUTLOOK...INCREASING CONFIDENCE IN IFR
CONDITIONS PRE-DAWN SUNDAY THROUGH MONDAY MORNING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...DENSE FOG ADVISORY UNTIL 8 AM EDT THIS MORNING FOR SCZ015-016-
020>022.
&&
$$
AREA FORECAST DISCUSSION
NWS DULUTH MN
642 AM CDT SAT MAR 26 2016
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 356 AM CDT SAT MAR 26 2016
A STATIONARY FRONT FROM A LOW IN THE CENTRAL PLAINS WILL CONTINUE
TO EXTEND THROUGH THE SE FORECAST AREA THROUGH TONIGHT AS THE LOW
LIFTS GRADUALLY INTO THE UPPER MIDWEST. THERE WILL BE COOLER NE
FLOW ON THE NORTHERN AND WESTERN SIDE OF THE FRONT. A WAVE OF
PCPN EARLY THIS MORNING...ASSOCIATED WITH A PASSING
SHORTWAVE...WILL GRADUALLY TAPER OFF LATER THIS MORNING.
HOWEVER...ANOTHER WAVE OF PCPN WILL LIFT INTO THE NORTHLAND
TONIGHT WHEN THE LOW MOVES INTO IOWA AND SE MINNESOTA/SW
WISCONSIN.
SURFACE TEMPERATURES WILL CLIMB TO THE 30S AND 40S TODAY...WITH
THE WARMEST TEMPERATURES ACROSS THE FAR SOUTHERN FORECAST AREA IN
THE WARM ZONE SOUTH AND EAST OF THE STATIONARY FRONT. TEMPERATURES
WILL THEN DIP INTO THE 20S AND 30S OVERNIGHT. THE RAP/NAM/GFS
MODEL SOUNDINGS INDICATE DEEP ENOUGH SATURATION THROUGH TONIGHT TO
RELIABLY FAVOR SNOW...EXCEPT WHERE NEAR SURFACE TEMPERATURES WILL
BE SUFFICIENTLY ABOVE FREEZING TO FAVOR RAIN. MUCH OF THE
LINGERING MIDDAY VERY LIGHT PCPN WILL LIKELY BE RAIN...EXCEPT
PERHAPS A MIX OF RAIN AND SNOW NEAR LAKE SUPERIOR. THE RAIN WILL
THEN TRANSITION BACK TO SNOW LATE THIS AFTERNOON AND THIS EVENING
WITH THE FALLING TEMPERATURES AND NEXT WAVE OF PCPN. SOME AREAS OF
THE NORTHLAND MAY GET 1 TO 3 INCHES OF SNOW ACCUMULATION
TONIGHT...INCLUDING THE NORTH AND SOUTH SHORES...THE TWIN PORTS
AND CLOQUET AREAS...AND TO NEAR AITKIN.
THERE COULD BE NARROW CORRIDOR OF SLEET TONIGHT NEAR THE
STATIONARY FRONT BETWEEN THE ZONES OF PREDOMINATELY RAIN AND
PREDOMINATELY SNOW. THERE COULD BE A CORRIDOR WHERE THE SNOW FALLS
THROUGH A WARM ENOUGH LAYER TO RESULT IN MELTING...THEN FALL BACK
INTO A SHALLOW COLD LAYER TO CAUSE SOME REFREEZING. HOWEVER...BASED
ON THE GFS/NAM SOUNDINGS...THE THREAT LOOKED TOO UNLIKELY OR TOO
NARROW IN COVERAGE TO CONSIDER ADDING THAT DETAIL TO THE FORECAST
AT THIS POINT. THE DAY SHIFT WILL HAVE A BETTER ABILITY TO
DETERMINE ITS THREAT WHEN THE RAP AND HRRR EXTEND THROUGH
TONIGHT.
THE NE FLOW OFF OF LAKE SUPERIOR...AND HIGH RELATIVELY HUMIDITY
TONIGHT...WILL LIKELY CAUSE MISTY CONDITIONS ACROSS LARGE PORTIONS
OF THE NORTHLAND. FOG IS POSSIBLE IN SOME AREAS...SUCH AS IN THE
HIGHER TERRAIN NEAR THE TWIN PORTS AND ASHLAND AREAS DOWNWIND AND
NEAR LAKE SUPERIOR. HOWEVER...WAS NOT CONFIDENT ENOUGH YET TO
INCLUDE IN THE FORECAST.
THE LOW WILL LIFT FROM WISCONSIN INTO MICHIGAN SUNDAY. THERE MAY
BE LINGERING LIGHT SNOW AND RAIN SUNDAY MORNING...BUT THE PCPN
SHOULD COME TO AN END BY NOON. THERE SHOULD ALSO BE SOME CLEARING
SKIES FROM THE WEST AS SURFACE HIGH PRESSURE MOVES INTO THE
REGION AND IN THE WAVE OF A PASSING SHORTWAVE TROUGH. INCREASED
TEMPERATURES...LEANING MORE ON THE WARMER NAM MOS COMPARED TO THE
COOLER GFS MOS CONSIDERING THE FAVORABILITY FOR WARMING FROM THE
SUNSHINE. A SUBTLE COLD FRONT WILL BEGIN TO MOVE INTO THE WESTERN
FORECAST AREA DURING THE LATE AFTERNOON OR EARLY EVENING.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 356 AM CDT SAT MAR 26 2016
THE FOCUS DURING THE EXTENDED PERIOD WILL BE ON A STRONG EARLY
SPRING STORM MID WEEK.
THE UPPER FLOW WILL START OUT NORTHWESTERLY OVER THE
NORTHLAND...WITH AN UPPER LOW OVER THE PACIFIC NORTHWEST. A
SHORTWAVE AND WEAK SURFACE LOW WILL MOVE THROUGH THE NORTHLAND
SUNDAY NIGHT. MOST OF THE MODELS DO NOT INDICATE MUCH PRECIP WITH
THESE FEATURES...BUT WE DO KEEP A LOW CHANCE FOR SOME SNOW/RAIN
OVER PARTS OF THE NORTHLAND AS IT MOVES THROUGH.
MONDAY AND MONDAY NIGHT SHOULD BE DRY WITH WEAK HIGH PRESSURE
PASSING THROUGH THE AREA.
THE UPPER LOW WILL DROP SOUTH OVER THE GREAT BASIN MONDAY NIGHT
THEN THE MODELS MOVE IT SLOWLY EAST INTO WEDNESDAY. A PIECE OF
SHORTWAVE ENERGY WILL MOVE NORTHEAST OUT OF THE LOW AND DEEPEN A
SURFACE LOW. THE NORTHLAND WILL START TO FEEL THE IMPACTS OF THESE
FEATURES AS EARLY AS TUESDAY...WITH A CHANCE FOR LIGHT SNOW/RAIN
OVER MAINLY SOUTHERN PORTIONS OF THE AREA. MODEL DIFFERENCES START
SHOWING UP TUESDAY...AND INCREASE THROUGH THE REMAINDER OF THE
PERIOD. SOME OF THE DIFFERENCES INCLUDE THE GFS MERGING A NORTHERN
STREAM WAVE WITH THE SOUTHERN STREAM WAVE ON WEDNESDAY DEEPENING
THE SURFACE LOW MUCH MORE THAN THE ECMWF/GEM. ALSO AS A RESULT OF
THE DEEPER LOW...IT IS MUCH SLOWER. ALL THE MODELS HAVE SHOWN BOTH
RUN TO RUN DIFFERENCES AS WELL AS DIFFERENCES IN HOW THEY HANDLE
THIS LOW. THE GFS HAS TRENDED FASTER AND A BIT WEAKER WITH THE
SURFACE LOW FROM 108-120 HOURS COMPARED WITH PREVIOUS RUNS.
PRECIPITATION SHOULD BECOME LIKELY FOR MOST OF THE AREA TUESDAY
NIGHT/WEDNESDAY THEN GRADUALLY DECREASE FROM WEST TO EAST
WEDNESDAY NIGHT INTO THURSDAY. THE ECMWF IS MORE PROGRESSIVE
MOVING THROUGH LOW THROUGH THE REGION...AS IT KEEPS THE NORTHERN
STREAM WAVE SEPARATE WHICH HELPS MOVE THE LOW ALONG.
PRECIPITATION TYPE WILL BE A TOUGH CALL...EVEN IN THE SHORT
TERM...BUT ESPECIALLY THIS FAR OUT WITH ALL THE MODEL DIFFERENCES.
WE HAVE A RAIN/SNOW MIX OVER NORTHERN AREAS OF MINNESOTA TUESDAY
NIGHT AND OVER PARTS OF THE FAR NORTH ON WEDNESDAY. COLDER AIR
WILL MOVE IN WEDNESDAY NIGHT INTO THURSDAY WITH A BETTER CHANCE
FOR SNOW. A FEW THUNDERSTORMS MAY ALSO OCCUR...MAINLY WEDNESDAY
INTO WEDNESDAY NIGHT. SIGNIFICANT PRECIPITATION WILL BE LIKELY
WITH THIS STORM...BUT JUST HOW MUCH SNOW OCCURS IS VERY DIFFICULT
TO DETERMINE AT THIS TIME. IF THE GFS VERIFIES...THERE WILL BE A
BETTER CHANCE FOR SIGNIFICANT SNOWFALL OVER MAINLY NORTHEAST
MINNESOTA.
MODEL DIFFERENCES CONTINUE THROUGH THE REST OF THE EXTENDED AS
WELL. HOWEVER...BOTH THE GFS AND ECMWF SHOW VERY COLD AIR MOVING
INTO THE REGION OVER THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 641 AM CDT SAT MAR 26 2016
A FRONTAL BOUNDARY AND AREA OF LOW PRESSURE WILL IMPACT THE
NORTHLAND THROUGH THE PERIOD. PERIODS OF SNOW OR RAIN WILL OCCUR
ACROSS MUCH OF THE NORTHLAND TODAY INTO MUCH OF TONIGHT. CEILINGS
WILL RANGE FROM VFR AT KINL TO IFR/MVFR MOST OTHER AREAS. EARLY
THIS MORNING...MAINLY SNOW WILL OCCUR OVER NORTHEAST MINNESOTA AND
FAR NORTHWEST WISCONSIN. AS THE BOUNDARY LAYER WARMS...MORE RAIN
WILL OCCUR. TONIGHT...THE PRECIPITATION WILL BECOME MOSTLY
SNOW...BUT IT WILL TAKE MUCH OF THE NIGHT TO COMPLETELY SWITCH
OVER AT KHYR.
THE PRECIPITATION WILL DIMINISH FROM NORTHWEST TO SOUTHEAST
TONIGHT INTO SUNDAY MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 36 28 43 27 / 70 80 20 20
INL 38 17 44 23 / 0 0 0 10
BRD 41 29 49 30 / 50 60 0 0
HYR 45 33 47 28 / 70 80 30 10
ASX 39 30 41 29 / 80 80 40 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ121-
140>143-146>148.
SMALL CRAFT ADVISORY UNTIL 4 AM CDT SUNDAY FOR LSZ144-145.
&&
$$
SHORT TERM...GROCHOCINSKI
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1035 AM EDT SAT MAR 26 2016
.SYNOPSIS... COOL HIGH PRESSURE WILL BUILD SOUTH INTO THE
AREA TODAY AND TONIGHT AS A WAVY FRONT STALLS ALONG THE SOUTHEAST
COAST. THE FRONT WILL LIFT NORTH ACROSS THE AREA AS A WARM FRONT LATE
SUNDAY AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES THROUGH
THE AREA ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1035 AM SATURDAY...
IT APPEARS THE COLD FRONT HAS FINALLY SETTLED INTO SC...AIDED SLOWLY
BY VERY SHALLOW (ONLY ~1000FT) NORTHEAST FLOW AND COLD ADVECTION.
ISENTROPIC LIFT ATOP THE COOL DOME IS ALSO WEAK WITH ONLY 10-20KT AT
290-295K PER RAP ANALYSIS. STRATUS HAS BEEN PATCH AND CONFINED TO
THE SOUTHERN CWA BUT IS STARTING TO FILL IN ACROSS THE PIEDMONT. THE
LACK OF STRATUS AND ONLY THIN CIRRUS TO FILTER THE SUN HAS ALLOWED
TEMPS TO WARM UP IN THE WESTERN AND CENTRAL PIEDMONT...SO HIGHS WILL
NEED TO BE RAISED A FEW DEGREES. SKIES WILL EVENTUALLY BECOME
OVERCAST BY THIS AFTERNOON...SO EXACTLY HOW MUCH ADDITIONAL WARMING
IS POSSIBLE IS TOUGH TO SAY. A BLEND OF GUIDANCE THAT APPEARS TO
AVE CAUGHT ON TO THE TREND SUGGESTS MANY LOCATIONS WILL HIT
60S...WITH MID/UPPER 40S IN THE CENTRAL AND NORTHERN PIEDMONT.
ISENTROPIC LIFT WILL INCREASE THIS AFTERNOON AND
EVENING...ESPECIALLY OVER THE COASTAL PLAIN...AS A WAVE OF LOW
PRESSURE DEVELOPS ALONG THE FRONT IN RESPONSE TO A LOW-AMPLITUDE
SHORTWAVE LIFTING OUT OF THE CENTRAL PLAINS TROUGH. THE CURRENT POP
FORECAST LOOKS PRETTY GOOD...SO WILL JUST MAKE MINOR CHANGES TO SLOW
THE ARRIVAL OF MORE WIDESPREAD RAIN...WHICH SHOULD BE MORE TOWARD
00Z PER HIRES GUIDANCE. CHANGES RESULT IN CHANCE POPS NORTHWEST AND
LIKELY POPS SOUTHEAST...WITH QPF RANGING FROM A FEW HUNDREDTHS
NORTHWEST TO AROUND A TENTH OF AN INCH SOUTHEAST.
THE CHANCE OF PATCHY LIGHT RAIN OR DRIZZLE WILL PERSIST OVERNIGHT.
LOWS OVERNIGHT IN THE UPPER 40S NW TO MID 50S SE.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 345 AM SATURDAY...
DREARY CLOUDY CONDITIONS ASSOCIATED WITH HYBRID DAMMING WILL
CONTINUE ON SUNDAY. THE WEAKENING FRONT TO OUR SOUTH IS EXPECTED
TO LIFT NORTH AS A WARM FRONT LATE IN THE AFTERNOON AND EVENING...
IN ADVANCE OF SHORTWAVE TROUGH AND ATTENDANT SFC FRONT ADVANCING
EASTWARD INTO CENTRAL AND SOUTHERN APPALACHIANS. RESULTANT WAA COUPLED
WITH ANY SHORTWAVE PERTURBATIONS EJECTING OUT AHEAD OF THE AFOREMENTIONED
UPSTREAM SHORTWAVE TROUGH WILL SUPPORT AN INCREASING CHANCE OF SHOWERS
SUNDAY AND SUNDAY NIGHT. THERE CONTINUES TO BE SIGNALS IN THE MODELS
OF A CLASSIC "CAROLINA SPLIT"...WHERE CENTRAL NC EXPERIENCES A SIGNIFICANT
REDUCTION/VOID IN PRECIP AS ENERGY/FORCING SPLITS TO OUR NW WITH THE PARENT S/W
TROUGH STAYING NORTH OF THE AREA AND TO OUR SOUTHEAST WITH ANOTHER POSSIBLE
COASTAL LOW DEVELOPMENT AND ASSOCIATED CONVECTION.
SHOULD BE A LITTLE WARMER GIVEN WEAKENING CAD. HIGHS IN THE LOWER 60S NORTH
TO NEAR 70S SOUTH WITH MINIMAL COOLING OVERNIGHT. LOWS IN THE MID 50S TO LOWER
60S.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 250 AM SATURDAY...
MON AND MON NIGHT: THERE COULD BE SOME LINGERING SHOWER ACTIVITY MON
MORN AS THE UPPER LEVEL TROUGH AXIS PASSES OVER NC...OTHERWISE
EXPECT THE SURFACE FRONT TO PUSH THROUGH DURING THE DAY MON...WITH
DRYING AND CAA BEHIND IT. BOTH THE GFS AND ECMWF MOVE THE FRONT
THROUGH AND THE RAIN OUT OF THE AREA BY MON NIGHT. GIVEN THE CURRENT
FROPA TIMING...THERE WILL BE QUITE A GRADIENT IN HIGHS MON... AROUND
70 DEGREES NW TO MID 70S SE. MON NIGHT LOWS IN THE LOW TO MID 40S.
TUE THROUGH WED: A RETURN OF DRY AND SLIGHTLY COOLER WEATHER FOR MID-
WEEK WITH HIGH PRESSURE BUILDING IN AT THE SURFACE AND RIDGING
ALOFT. HIGHS IN THE MID TO UPPER 60S TUE AND WED. LOWS MODERATING
FROM UPPER LOW 40S TUE NIGHT TO MID TO AROUND 50 DEGREES WED NIGHT.
THE NEXT ROUND OF RAIN COULD MOVE INTO THE WEST AS EARLY AS WED
NIGHT AS A FRONTAL SYSTEM APPROACHES FROM THE WEST...BUT WILL MAY
HOLD OFF UNTIL THU. THERE IS STILL A LARGE DIFFERENCE IN TIMING
BETWEEN THE MODELS...GFS FASTER THAN ECMWF.
THU THROUGH SAT: AS A LOW PRESSURE SYSTEM MOVES THROUGH THE MIDWEST
FROM CO TO THE GREAT LAKES...THE ASSOCIATED COLD FRONT WILL PUSH
EASTWARD TOWARD THE CAROLINAS. THE SURFACE HIGH WILL BE PUSHED OUT
OF THE AREA AS THE WARM FRONT LIFTS NORTHWARD THROUGH CENTRAL NC WED
NIGHT. MEANWHILE...A SURFACE LOW WILL DEVELOP OVER THE TX GULF COAST
AND MOVE NE ALONG THE FRONT. TIMING OF RAINFALL ONSET...DURATION...
AND FROPA TIMING ARE ALL STILL FAIRLY UNCERTAIN. GENERALLY THOUGH...
EXPECT MODERATING TEMPS AND INCREASING RAIN CHANCES THU THROUGH FRI.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
AS OF 655 AM SATURDAY...
24 HOUR TAF PERIOD: HIGH PRESSURE WILL WEDGE SOUTH INTO THE AS THE
FRONT STALLS JUST SOUTH AND EAST OF CENTRAL NC. MVFR CEILINGS WILL
OVERSPREAD THE AREA WITH THE ONSET OF SOUTHERLY MOIST UPGLIDE ATOP
THE SHALLOW NELY FLOW NEAR THE SURFACE. ADDITIONALLY LIGHT RAIN
AND/OR DRIZZLE WILL BE POSSIBLE...WITH THE BEST PRECIP CHANCES
EXPECTED AT KFAY. CEILINGS SHOULD CONTINUE TO LOWER TO IFR AND
POSSIBLY LIFR THROUGH THE EVENING AND OVERNIGHT HOURS WITH DRIZZLE
POSSIBLE EVERYWHERE.
OUTLOOK: SUB-VFR CEILINGS SHOULD PERSIST THROUGH SUNDAY WITH
INCREASING RAIN CHANCES LATE SUNDAY AND SUNDAY NIGHT AS A WAVE OF
LOW PRESSURE DEVELOPS AND TRACKS NE ALONG THE FRONT. VFR CONDITIONS
ARE EXPECTED TO RETURN BY MONDAY EVENING AS DRIER AIR ADVECTS INTO
THE AREA BEHIND A COLD FRONT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...22/CBL
SHORT TERM...CBL
LONG TERM...KCP
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1046 AM EDT SAT MAR 26 2016
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST TODAY BEFORE WEDGING SOUTH ALONG
THE EASTERN SLOPES OF THE APPALACHIANS THIS AFTERNOON INTO SUNDAY.
THE NEXT COLD FRONT APPROACHES THE REGION LATE SUNDAY NIGHT AND
CROSSES THROUGH THE AREA DURING THE DAY MONDAY. WEAK HIGH PRESSURE
FOLLOWS THIS FRONT WITH OVERALL DRY WEATHER INTO MIDWEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM EDT SATURDAY...
MINOR CHANGES TO THE GRIDS MAINLY TO REDUCE SKY COVER IN THE WEST
TODAY AS EFFECTS OF WEDGING ARE MORE PRONOUNCED EAST OF THE
MOUNTAINS ALONG WITH CLOUDS FROM DEVELOPING LOW PRESSURE OVER THE
SOUTHEAST WHERE MUCH HEAVIER CLOUD COVER EXISTS. BUMPED TEMPS UP
A DEGREE OR TWO IN THE AREAS OF REDUCED CLOUD COVER.
PREVIOUS VALID DISCUSSION...
AS OF 245 AM EDT SATURDAY...
LOW LEVEL COOL AIR WEDGE WILL CONTINUE TO SLOWLY DEEPEN TODAY AS HIGH
PRESSURE SHIFTS EAST TO ALONG THE MID ATLANTIC COAST THIS AFTERNOON.
WEAK STALLED FRONT TO THE SOUTH REMAINS THE SOURCE FOR MOISTURE TO
SHIFT BACK NORTH INTO THE AREA AS A FAINT SHORTWAVE EJECTING EAST
CAUSES WEAK LOW PRESSURE TO DEVELOP ALONG THE BOUNDARY OVER THE
SOUTHEAST STATES LATER TODAY. MODELS SUGGEST THIS ALONG WITH INCREASING
ONSHORE FLOW WILL BRING DEEPENING MOISTURE BACK NORTH AHEAD OF THE WAVE
BY THIS AFTERNOON WITH LINGERING LOW LEVEL MOISTURE LOCKED IN
FROM THE BLUE RIDGE EAST THROUGH THE OVERNIGHT. HOWEVER FORECAST
ISENTROPIC LIFT LOOKS QUITE WEAK AND WITH THE LOW LEVEL FLOW MORE
EAST/NE THAN SOUTHEAST TODAY THINK GUIDANCE LIKELY OVERDONE WITH
PRECIP PUSHING WELL NORTH ACROSS THE CWA BY LATE IN THE DAY. CANT
TOTALLY RULE OUT SOME SPOTTY -RA REACHING THE FAR SOUTH/SE LATE
ALONG THE PROGGED 85H THETA-E GRADIENT AND SUPPORTED BY THE LATEST
HIRES-ARW/ENSEMBLES. THUS INCLUDING SOME 20/30 POPS MAINLY SE
THIRD FOR POSSIBLE PATCHY -RA LATER THIS AFTERNOON BUT DRY
ELSEWHERE.
OTRW CLOUD COVER AND TEMPS REMAIN TRICKY GIVEN POTENTIAL FOR DRY
AIR TO MIX OUT LOW CLOUDS THIS MORNING BEFORE MOISTURE DEEPENS
AGAIN FROM THE SOUTH LATER ON. MOST MOS GUIDANCE QUITE COOL WITHIN
THE WEDGE BASED ON HAVING A THICKER CLOUD CANOPY ALL DAY WHICH
LOOKS OVERDONE. HOWEVER CURRENT ECMWF MOS APPEARS WAY TOO WARM SO
KEPT HIGHS CLOSE TO PREVIOUS PENDING CLOUDS WHICH COULD RESULT IN
HIGH TEMPS BEING MUCH COOLER THAN EXPECTED.
INITIAL BATCH OF DEEPER MOISTURE EXITS TO THE EAST LATER THIS EVENING
BUT LIKELY REPLACED BY LINGERING UPSLOPE AS THE BOUNDARY LAYER FLOW
TURNS MORE SE. THIS COULD LEAD TO MORE IN THE WAY OF DRIZZLE/FOG ESPCLY
SOUTHERN BLUE RIDGE AND POINTS EAST OVERNIGHT WITH WARM ADVECTION OVER
TOP THE COOL POOL. HOWEVER ANY ADDITIONAL QPF QUITE LIGHT AND MAINLY
SOUTHERN TIER WITH POSSIBLE DENSE FOG I-77 CORRIDOR UNDER LOWERING
CLOUD BASES OVERNIGHT DESPITE LACK OF MUCH SIGNIFICANT PRECIP. THEREFORE
RUNNING WITH DECREASING POPS SOUTH/SE SECTIONS AFTER MIDNIGHT WITH
TREND TOWARD MORE PATCHY DRIZZLE LATE AND LITTLE PRECIP WEST OF
THE BLUE RIDGE GIVEN MORE DOWNSLOPING FLOW. LOWS MOSTLY IN THE 40S
AND PERHAPS ONLY NEAR 50 SOUTHEAST WITH CLOUDS AROUND AND LOW
LEVEL MOISTURE IN PLACE.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 225 AM EDT SATURDAY...
HIGH PRESSURE WILL REMAIN WEDGED ACROSS THE MID ATLANTIC REGION
SOUTH INTO THE CAROLINAS SUNDAY. THE WEDGE WILL START TO ERODE
ACROSS SOUTHWESTERN VIRGINIA AND SOUTHEASTERN WEST VIRGINIA SUNDAY
AFTERNOON BUT WILL BE ENTRENCHED ALONG AND EAST OF THE BLUE RIDGE
INTO SUNDAY NIGHT. WARM MOIST AIR OVERRUNNING THE WEDGE WILL KEEP
LOW CLOUDS...RAIN...AND DRIZZLE ALONG AND EAST OF THE BLUE RIDGE
SUNDAY AND SUNDAY NIGHT. INSIDE THE WEDGE...TEMPERATURES WILL REMAIN
COOL IN THE UPPER 50S TO LOWER 60S. OUTSIDE OF THE
WEDGE...ESPECIALLY IN THE BLUEFIELD-RICHLANDS AREA AND THE MOUNTAIN
EMPIRE...SUNDAY`S TEMPERATURES COULD WARM INTO THE LOWER 70S.
A QUICK MOVING COLD FRONT WILL TRACK ACROSS THE OHIO VALLEY SUNDAY
AFTERNOON AND EVENING. WITH PRESSURE FALLS OVER THE OHIO VALLEY AND
INCREASE MIXING WITH A SOUTHWESTERLY 40 KT LOW LEVEL JET...THE WEDGE
WILL ERODE OVERNIGHT. AREAS IN THE WEDGE SUNDAY WILL SEE
TEMPERATURES WARM THROUGH THE NIGHT AND INTO THE DAY MONDAY AS THE
FRONT MOVES OVER THE REGION. AREAS EAST OF THE BLUE RIDGE SHOULD SEE
TEMPERATURES WARMING INTO THE LOWER 70S MONDAY AFTERNOON. COLD AIR
ADVECTING IN ACROSS THE MOUNTAINS MONDAY WILL HAVE HIGH TEMPERATURES
IN THE UPPER 50S TO LOWER 60S.
MODERATE RAINFALL WITH THE FRONT COULD BRING A QUARTER TO HALF INCH
/0.25-0.50/ OF RAIN TO SOUTHWESTERN VIRGINIA AND SOUTHEASTERN WEST
VIRGINIA. AREAS ALONG AND EAST OF THE BLUE RIDGE MAY SEE UP TO A
TENTH /0.10/ OF AN INCH WHILE IN THE WEDGE...THEN POSSIBLY A QUARTER
/0.25/ OF AN INCH WITH THE PASSING OF THE FRONT. ALSO BEHIND THE
FRONT...PRESSURE RISES AND A TIGHT GRADIENT WILL BRING BREEZY AND
GUSTY CONDITIONS TO THE AREA MONDAY. THESE WINDS WILL RELAX MONDAY
NIGHT AS HIGH PRESSURE BUILDS WEST ACROSS THE REGION.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 245 PM EDT FRIDAY...
TUESDAY AND WEDNESDAY WILL BE DRY AND PLEASANT DAYS AS THE REGION
REMAINS UNDER THE INFLUENCE OF A SURFACE HIGH THAT WILL SLOWLY DRIFT
FROM SOUTHERN ONTARIO SOUTHEAST TO THE NEW ENGLAND STATES. MEANWHILE
A SURFACE LOW ACROSS THE NORTHERN PLAINS WILL BEGIN TO DEEPEN AS IT
MOVES E/NE INTO SOUTHERN CANADA. A COLD FRONT ASSOCIATED WITH THIS
SYSTEM WILL CROSS OUR AREA ON THURSDAY BRINGING SHOWERS AND POSSIBLY
THUNDERSTORMS. ON FRIDAY ADDITIONAL SHOWERS ARE POSSIBLE AS A
SURFACE LOW DEVELOPS ACROSS THE SOUTHEAST STATES AND SKIRTS JUST TO
OUR EAST BY FRIDAY EVENING. SURFACE TEMPS DURING THIS PERIOD WILL BE
NORMAL TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
AS OF 700 AM EDT SATURDAY...
BRIEF CLEARING OVERNIGHT HAS ALLOWED PATCHY DENSE FOG TO DEVELOP
ACROSS THE VALLEYS WITH LIFR AT KLWB IN FREEZING FOG WHICH IS LIKELY
TO LINGER INTO MID MORNING BEFORE FADING. OTRW SEEING MAINLY VFR
TO INIT THIS MORNING WITH AREAS OF VFR STRATO-CU CIGS ALONG THE
BLUE RIDGE. EXPECTING SOME OF THIS CLOUD COVER TO WORK NORTH
ACROSS MANY OF THE TAF SITES THIS MORNING WITH CIGS BETWEEN 3-5K
FEET.
HOWEVER FORECAST UNCERTAINTY CONTINUES IN REGARD TO CLOUD COVER
BY THIS AFTERNOON WITH POTENTIAL FOR ANY LOWER CIGS THIS MORNING TO
MIX OUT IN ALL EXCEPT THE FAR WEST AND ACROSS THE SOUTH WHERE
CLOSER TO A STALLED FRONT. DEEPENING WEDGE DEVELOPMENT THOUGH ALONG
WITH MORE OF AN EASTERLY TRAJECTORY LIKELY TO SWING LOW LEVEL
MOISTURE NORTHWEST BY LATE AFTERNOON WITH MVFR CIGS POSSIBLE BACK
TO THE BLUE RIDGE. THINK NORTHERN SECTIONS FROM KLWB TO KLYH HAVE
THE BEST SHOT AT SEEING MORE IN THE WAY OF VFR CIGS LONGER WHILE
ELSEWHERE APPEARS A PERIOD OF VFR BEFORE TRENDING TO HIGH END MVFR
DURING THE AFTERNOON FROM SE TO NW. THUS KEEPING MOST CIGS WITHIN
LOW END VFR INTO THE AFTERNOON PENDING JUST HOW WIDESPREAD CURRENT
DEVELOPING STRATO-CU GETS IN THE FACE OF HEATING.
LATEST GUIDANCE SUGGESTS THAT LOW LEVEL MOISTURE WITHIN THE WEDGE COULD
SPREAD ACROSS THE ENTIRE REGION TONIGHT RESULTING IN WIDESPREAD
SUB-VFR INCLUDING AREAS OF DRIZZLE/-RA FROM THE BLUE RIDGE EAST BY
SUNDAY MORNING. THIS MOST APT TO OCCUR AROUND KDAN THIS EVENING
PER LATEST HRRR AND ALONG THE BLUE RIDGE EASTWARD INCLUDING
KROA/KBCB TO KLYH OVERNIGHT WHERE COULD FALL INTO LIFR/IFR CIGS
WITH MVFR TO OCNL IFR VSBYS. APPEARS DOWNSLOPING SE FLOW WILL
KEEP KBLF/KLWB NO WORSE THAN MVFR WITH POSSIBLE LOW CIGS AND FOG
SPILLING INTO KLWB LATE.
THESE LOW CIGS LIKELY CONTINUE INTO EARLY SUNDAY AFTERNOON BEFORE
POTENTIALLY SCATTERING OUT FROM THE WEST AS THE WEDGE RETREATS
NORTHEAST AHEAD OF THE NEXT COLD FRONT.
EXTENDED DISCUSSION...
BY SUNDAY EVENING...AN UPPER TROUGH AND ASSOCIATED FRONTAL SYSTEM
WILL BE APPROACHING FROM THE WEST WITH MVFR-IFR CIGS/VSBYS LIKELY
OVERNIGHT IN RAIN SHOWERS FROM WEST TO EAST. BREEZY AND COOLER
CONDITIONS WILL FOLLOW FOR THE FIRST PART OF NEXT WEEK AS HIGH
PRESSURE BUILDS INTO THE REGION ALLOWING VFR CONDITIONS TO RETURN
BY MONDAY AFTERNOON. THE POSSIBLE DELAYED EXCEPTION WILL BE ACROSS
THE UPSLOPE AREAS OF WEST VA WHERE LOW CLOUDS AND MVFR CIGS COULD
LINGER INTO MONDAY AFTERNOON. VFR SHOULD THEN PREVAIL TUESDAY INTO
WEDNESDAY UNDER WEAK HIGH PRESSURE BEHIND THE FRONT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...CF/JH
NEAR TERM...PC/WP
SHORT TERM...RCS
LONG TERM...CF
AVIATION...JH/PH/RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
722 AM EDT SAT MAR 26 2016
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST TODAY BEFORE WEDGING SOUTH ALONG
THE EASTERN SLOPES OF THE APPALACHIANS THIS AFTERNOON INTO SUNDAY.
THE NEXT COLD FRONT APPROACHES THE REGION LATE SUNDAY NIGHT AND
CROSSES THROUGH THE AREA DURING THE DAY MONDAY. WEAK HIGH PRESSURE
FOLLOWS THIS FRONT WITH OVERALL DRY WEATHER INTO MIDWEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 245 AM EDT SATURDAY...
LOW LEVEL COOL AIR WEDGE WILL CONTINUE TO SLOWLY DEEPEN TODAY AS HIGH
PRESSURE SHIFTS EAST TO ALONG THE MID ATLANTIC COAST THIS AFTERNOON.
WEAK STALLED FRONT TO THE SOUTH REMAINS THE SOURCE FOR MOISTURE TO
SHIFT BACK NORTH INTO THE AREA AS A FAINT SHORTWAVE EJECTING EAST
CAUSES WEAK LOW PRESSURE TO DEVELOP ALONG THE BOUNDARY OVER THE
SOUTHEAST STATES LATER TODAY. MODELS SUGGEST THIS ALONG WITH INCREASING
ONSHORE FLOW WILL BRING DEEPENING MOISTURE BACK NORTH AHEAD OF THE WAVE
BY THIS AFTERNOON WITH LINGERING LOW LEVEL MOISTURE LOCKED IN
FROM THE BLUE RIDGE EAST THROUGH THE OVERNIGHT. HOWEVER FORECAST
ISENTROPIC LIFT LOOKS QUITE WEAK AND WITH THE LOW LEVEL FLOW MORE
EAST/NE THAN SOUTHEAST TODAY THINK GUIDANCE LIKELY OVERDONE WITH
PRECIP PUSHING WELL NORTH ACROSS THE CWA BY LATE IN THE DAY. CANT
TOTALLY RULE OUT SOME SPOTTY -RA REACHING THE FAR SOUTH/SE LATE
ALONG THE PROGGED 85H THETA-E GRADIENT AND SUPPORTED BY THE LATEST
HIRES-ARW/ENSEMBLES. THUS INCLUDING SOME 20/30 POPS MAINLY SE
THIRD FOR POSSIBLE PATCHY -RA LATER THIS AFTERNOON BUT DRY
ELSEWHERE.
OTRW CLOUD COVER AND TEMPS REMAIN TRICKY GIVEN POTENTIAL FOR DRY
AIR TO MIX OUT LOW CLOUDS THIS MORNING BEFORE MOISTURE DEEPENS
AGAIN FROM THE SOUTH LATER ON. MOST MOS GUIDANCE QUITE COOL WITHIN
THE WEDGE BASED ON HAVING A THICKER CLOUD CANOPY ALL DAY WHICH
LOOKS OVERDONE. HOWEVER CURRENT ECMWF MOS APPEARS WAY TOO WARM SO
KEPT HIGHS CLOSE TO PREVIOUS PENDING CLOUDS WHICH COULD RESULT IN
HIGH TEMPS BEING MUCH COOLER THAN EXPECTED.
INITIAL BATCH OF DEEPER MOISTURE EXITS TO THE EAST LATER THIS EVENING
BUT LIKELY REPLACED BY LINGERING UPSLOPE AS THE BOUNDARY LAYER FLOW
TURNS MORE SE. THIS COULD LEAD TO MORE IN THE WAY OF DRIZZLE/FOG ESPCLY
SOUTHERN BLUE RIDGE AND POINTS EAST OVERNIGHT WITH WARM ADVECTION OVER
TOP THE COOL POOL. HOWEVER ANY ADDITIONAL QPF QUITE LIGHT AND MAINLY
SOUTHERN TIER WITH POSSIBLE DENSE FOG I-77 CORRIDOR UNDER LOWERING
CLOUD BASES OVERNIGHT DESPITE LACK OF MUCH SIGNIFICANT PRECIP. THEREFORE
RUNNING WITH DECREASING POPS SOUTH/SE SECTIONS AFTER MIDNIGHT WITH
TREND TOWARD MORE PATCHY DRIZZLE LATE AND LITTLE PRECIP WEST OF
THE BLUE RIDGE GIVEN MORE DOWNSLOPING FLOW. LOWS MOSTLY IN THE 40S
AND PERHAPS ONLY NEAR 50 SOUTHEAST WITH CLOUDS AROUND AND LOW
LEVEL MOISTURE IN PLACE.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 225 AM EDT SATURDAY...
HIGH PRESSURE WILL REMAIN WEDGED ACROSS THE MID ATLANTIC REGION
SOUTH INTO THE CAROLINAS SUNDAY. THE WEDGE WILL START TO ERODE
ACROSS SOUTHWESTERN VIRGINIA AND SOUTHEASTERN WEST VIRGINIA SUNDAY
AFTERNOON BUT WILL BE ENTRENCHED ALONG AND EAST OF THE BLUE RIDGE
INTO SUNDAY NIGHT. WARM MOIST AIR OVERRUNNING THE WEDGE WILL KEEP
LOW CLOUDS...RAIN...AND DRIZZLE ALONG AND EAST OF THE BLUE RIDGE
SUNDAY AND SUNDAY NIGHT. INSIDE THE WEDGE...TEMPERATURES WILL REMAIN
COOL IN THE UPPER 50S TO LOWER 60S. OUTSIDE OF THE
WEDGE...ESPECIALLY IN THE BLUEFIELD-RICHLANDS AREA AND THE MOUNTAIN
EMPIRE...SUNDAY`S TEMPERATURES COULD WARM INTO THE LOWER 70S.
A QUICK MOVING COLD FRONT WILL TRACK ACROSS THE OHIO VALLEY SUNDAY
AFTERNOON AND EVENING. WITH PRESSURE FALLS OVER THE OHIO VALLEY AND
INCREASE MIXING WITH A SOUTHWESTERLY 40 KT LOW LEVEL JET...THE WEDGE
WILL ERODE OVERNIGHT. AREAS IN THE WEDGE SUNDAY WILL SEE
TEMPERATURES WARM THROUGH THE NIGHT AND INTO THE DAY MONDAY AS THE
FRONT MOVES OVER THE REGION. AREAS EAST OF THE BLUE RIDGE SHOULD SEE
TEMPERATURES WARMING INTO THE LOWER 70S MONDAY AFTERNOON. COLD AIR
ADVECTING IN ACROSS THE MOUNTAINS MONDAY WILL HAVE HIGH TEMPERATURES
IN THE UPPER 50S TO LOWER 60S.
MODERATE RAINFALL WITH THE FRONT COULD BRING A QUARTER TO HALF INCH
/0.25-0.50/ OF RAIN TO SOUTHWESTERN VIRGINIA AND SOUTHEASTERN WEST
VIRGINIA. AREAS ALONG AND EAST OF THE BLUE RIDGE MAY SEE UP TO A
TENTH /0.10/ OF AN INCH WHILE IN THE WEDGE...THEN POSSIBLY A QUARTER
/0.25/ OF AN INCH WITH THE PASSING OF THE FRONT. ALSO BEHIND THE
FRONT...PRESSURE RISES AND A TIGHT GRADIENT WILL BRING BREEZY AND
GUSTY CONDITIONS TO THE AREA MONDAY. THESE WINDS WILL RELAX MONDAY
NIGHT AS HIGH PRESSURE BUILDS WEST ACROSS THE REGION.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 245 PM EDT FRIDAY...
TUESDAY AND WEDNESDAY WILL BE DRY AND PLEASANT DAYS AS THE REGION
REMAINS UNDER THE INFLUENCE OF A SURFACE HIGH THAT WILL SLOWLY DRIFT
FROM SOUTHERN ONTARIO SOUTHEAST TO THE NEW ENGLAND STATES. MEANWHILE
A SURFACE LOW ACROSS THE NORTHERN PLAINS WILL BEGIN TO DEEPEN AS IT
MOVES E/NE INTO SOUTHERN CANADA. A COLD FRONT ASSOCIATED WITH THIS
SYSTEM WILL CROSS OUR AREA ON THURSDAY BRINGING SHOWERS AND POSSIBLY
THUNDERSTORMS. ON FRIDAY ADDITIONAL SHOWERS ARE POSSIBLE AS A
SURFACE LOW DEVELOPS ACROSS THE SOUTHEAST STATES AND SKIRTS JUST TO
OUR EAST BY FRIDAY EVENING. SURFACE TEMPS DURING THIS PERIOD WILL BE
NORMAL TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 700 AM EDT SATURDAY...
BRIEF CLEARING OVERNIGHT HAS ALLOWED PATCHY DENSE FOG TO DEVELOP
ACROSS THE VALLEYS WITH LIFR AT KLWB IN FREEZING FOG WHICH IS LIKELY
TO LINGER INTO MID MORNING BEFORE FADING. OTRW SEEING MAINLY VFR
TO INIT THIS MORNING WITH AREAS OF VFR STRATO-CU CIGS ALONG THE
BLUE RIDGE. EXPECTING SOME OF THIS CLOUD COVER TO WORK NORTH
ACROSS MANY OF THE TAF SITES THIS MORNING WITH CIGS BETWEEN 3-5K
FEET.
HOWEVER FORECAST UNCERTAINTY CONTINUES IN REGARD TO CLOUD COVER
BY THIS AFTERNOON WITH POTENTIAL FOR ANY LOWER CIGS THIS MORNING TO
MIX OUT IN ALL EXCEPT THE FAR WEST AND ACROSS THE SOUTH WHERE
CLOSER TO A STALLED FRONT. DEEPENING WEDGE DEVELOPMENT THOUGH ALONG
WITH MORE OF AN EASTERLY TRAJECTORY LIKELY TO SWING LOW LEVEL
MOISTURE NORTHWEST BY LATE AFTERNOON WITH MVFR CIGS POSSIBLE BACK
TO THE BLUE RIDGE. THINK NORTHERN SECTIONS FROM KLWB TO KLYH HAVE
THE BEST SHOT AT SEEING MORE IN THE WAY OF VFR CIGS LONGER WHILE
ELSEWHERE APPEARS A PERIOD OF VFR BEFORE TRENDING TO HIGH END MVFR
DURING THE AFTERNOON FROM SE TO NW. THUS KEEPING MOST CIGS WITHIN
LOW END VFR INTO THE AFTERNOON PENDING JUST HOW WIDESPREAD CURRENT
DEVELOPING STRATO-CU GETS IN THE FACE OF HEATING.
LATEST GUIDANCE SUGGESTS THAT LOW LEVEL MOISTURE WITHIN THE WEDGE COULD
SPREAD ACROSS THE ENTIRE REGION TONIGHT RESULTING IN WIDESPREAD
SUB-VFR INCLUDING AREAS OF DRIZZLE/-RA FROM THE BLUE RIDGE EAST BY
SUNDAY MORNING. THIS MOST APT TO OCCUR AROUND KDAN THIS EVENING
PER LATEST HRRR AND ALONG THE BLUE RIDGE EASTWARD INCLUDING
KROA/KBCB TO KLYH OVERNIGHT WHERE COULD FALL INTO LIFR/IFR CIGS
WITH MVFR TO OCNL IFR VSBYS. APPEARS DOWNSLOPING SE FLOW WILL
KEEP KBLF/KLWB NO WORSE THAN MVFR WITH POSSIBLE LOW CIGS AND FOG
SPILLING INTO KLWB LATE.
THESE LOW CIGS LIKELY CONTINUE INTO EARLY SUNDAY AFTERNOON BEFORE
POTENTIALLY SCATTERING OUT FROM THE WEST AS THE WEDGE RETREATS
NORTHEAST AHEAD OF THE NEXT COLD FRONT.
EXTENDED DISCUSSION...
BY SUNDAY EVENING...AN UPPER TROUGH AND ASSOCIATED FRONTAL SYSTEM
WILL BE APPROACHING FROM THE WEST WITH MVFR-IFR CIGS/VSBYS LIKELY
OVERNIGHT IN RAIN SHOWERS FROM WEST TO EAST. BREEZY AND COOLER
CONDITIONS WILL FOLLOW FOR THE FIRST PART OF NEXT WEEK AS HIGH
PRESSURE BUILDS INTO THE REGION ALLOWING VFR CONDITIONS TO RETURN
BY MONDAY AFTERNOON. THE POSSIBLE DELAYED EXCEPTION WILL BE ACROSS
THE UPSLOPE AREAS OF WEST VA WHERE LOW CLOUDS AND MVFR CIGS COULD
LINGER INTO MONDAY AFTERNOON. VFR SHOULD THEN PREVAIL TUESDAY INTO
WEDNESDAY UNDER WEAK HIGH PRESSURE BEHIND THE FRONT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...CF/JH
NEAR TERM...WP
SHORT TERM...RCS
LONG TERM...CF
AVIATION...JH/PH/RAB
AREA FORECAST DISCUSSION
NWS NEW YORK NY
407 PM EDT SAT MAR 26 2016
.SYNOPSIS...
HIGH PRESSURE REMAINS ALONG THE NEW ENGLAND COAST TONIGHT...AND
THEN RETREATS TO THE EAST ON SUNDAY AS LOW PRESSURE APPROACHES
FROM THE MIDWEST. THE LOWS PASSES TO THE NORTH ON MONDAY...SENDING
A COLD FRONT ACROSS THE AREA. CANADIAN HIGH PRESSURE SETTLES IN
THROUGH WEDNESDAY...FOLLOWED BY AN APPROACHING FRONTAL SYSTEM ON
THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
STRATUS THAT IMPACTED LI/CT AND EASTERN PORTIONS OF THE LOWER
HUDSON VALLEY THIS AFT HAS ALL BUT DISSIPATED WITH THE EXCEPTION
OF EASTERN LI SOUND. THIS WILL BE SHORT-LIVED HOWEVER AS A BANK OF
STRATUS ABOUT 20 MILES SOUTH OF LI RETURNS NORTH IN A LIGHT E/SE
FLOW. THE EXPANSE AND COVERAGE IS IN QUESTION...BUT THERE IS
MODERATE CONFIDENCE OF THE LOW CLOUDS MOVING INTO THE SOUTH
SHORE OF LI AND SE CT THIS EVENING...AND THEN GRADUALLY EXPANDING
NW ACROSS THE INTERIOR. PREFERENCE HERE WAS TO FOLLOW HIRES
MODELS...IN PARTICULAR THE HRRR AND NAM. FOG IS NOT EXPECTED AS
THE SUB-CLOUD LAYER LOOKS TO BE TOO DRY.
OTHERWISE...HIGH PRESSURE REMAINS NEARLY STATIONARY ALONG THE NEW
ENGLAND COAST. THIS WILL RESULT IN A E/SE FLOW...WHICH BY DAYBREAK
BACKS MORE TO THE E/NE AS A FRONTAL WAVE DEVELOPS OFF THE MID
ATLANTIC COAST.
OVERNIGHT LOWS WILL BE SEASONABLE IN THE 30S.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
PROGRESSIVE UPPER FLOW ACROSS THE LOWER 48 WILL FEATURE AN
AMPLIFYING SHORT WAVE TROF OVER THE MIDWEST ON SUN THAT TRACKS
QUICKLY ENE AND THROUGH THE NE ON MON. THE ASSOCIATED SFC LOW
WILL TRACK ACROSS THE GREAT LAKES SUN NIGHT AND THEN OCCLUDES TO
THE NORTH ON MON. THE OCCLUDED FRONT AND POSSIBLY A TRIPLE POINT
LOW PASS NEAR THE AREA DURING THE LATE MORNING HOURS. THE AREA
MAY BRIEFLY WARM SECTOR...BUT INSTABILITY IS WEAK AT BEST DUE TO
THE MARINE LAYER. WEAK INSTABILITY ALOFT COULD TRIGGER ISOLATED
CONVECTION...BUT CONFIDENCE IS TOO LOW TO MENTION IN FORECAST.
THUS...LOOKING AT A MAINLY WARM ADVECTION EVENT WITH RAIN WORKING
INTO THE AREA LATE SUN NIGHT AND CONTINUING INTO THE MORNING. THE
FAST NATURE OF THE SYSTEM WILL KEEP RAINFALL AMOUNTS UNDER AN
INCH. IN ADDITION...WITH THE CLOSE PROXIMITY OF THE WARM FRONT
LATE SUN NIGHT INTO MON MORNING...AREAS OF FOG WILL LIKELY
DEVELOP.
OCCLUDED FRONT PASSES TO THE EAST BY EARLY AFTERNOON WITH
CONDITIONS QUICKLY DRYING OUT WITH A GUSTY W/SW FLOW DEVELOPING.
AS FOR TEMPS...HIGH ON SUN WILL BE SIMILAR TO TODAY...PERHAPS
SLIGHTLY WARMER ACROSS THE INTERIOR. LOWS SUN NIGHT WILL BE
MILDER WITH THE CLOUD COVER RANGING FROM THE UPPER 30S TO MID 40S.
IT WILL BE WARMER AS WELL ON MON WITH READINGS INTO THE MID AND
UPPER 50S.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODELS ARE IN GOOD AGREEMENT WITH THE LARGE SCALE PATTERN ACROSS
NOAM...TRANSITIONING FROM A SPLIT FLOW TO A HIGHLY AMPLIFIED PATTERN
BY THE END OF THE PERIOD. UPPER TROUGH AXIS SHIFTS E OF THE AREA MON
NIGHT WITH DEEP LAYERED RIDGING BUILDING FROM THE MIDWEST THROUGH
THE MIDDLE OF THE WEEK. MEANWHILE...CUTOFF LOW OVER THE SRN ROCKIES
WILL CONSOLIDATE WITH A DIGGING WRN CANADIAN TROUGH AND CONTINUE
EWD...IMPACTING THE NORTHEAST THU/FRI.
IN TERMS OF SENSIBLE WEATHER...THE COMBINATION OF STRONG CAA AND
SHARP PRESSURE RISES IN THE WAKE OF STRENGTHENING LOW PRES
DEPARTING TO THE NE MON NIGHT WILL RESULT IN STRONG GUSTY WINDS
THROUGH TUE. GUSTS COULD APPROACH OR EVEN REACH WIND ADVSY
LEVELS IN SOME SPOTS...BUT CURRENTLY LOOKS LIKE MOST LOCATIONS
WILL FALL JUST SHORT. WINDS ABATE TUE NIGHT AS THE HIGH MOVES OHD
AND THE OFFSHORE ON WED WITH DRY AND SEASONABLE WEATHER. SW WINDS
WILL INCREASE AGAIN LATE WED NIGHT AND THU BETWEEN THE DEPARTING
HIGH AND LOW PRES MOVING TOWARDS/THROUGH THE GREAT LAKES...BUT
THIS IS WHERE GUIDANCE STARTS TO DIVERGE. THERE IS SIGNIFICANT
UNCERTAINTY REGARDING THE EXACT DETAILS OF THIS LATE WEEK STORM
SYSTEM...MAINLY IN TIMING AND STRENGTH...ALTHOUGH UNSETTLED
WEATHER APPEARS LIKELY DURING THIS TIME AS LOW PRES TRACKS THROUGH
THE GREAT LAKES AND INTO SE CANADA.
OTHER THAN TUE NIGHT WHERE CONDS APPEAR OPTIMAL FOR RADIATIONAL
COOLING RESULTING IN LOWS SLIGHTLY COLDER THAN NORMAL...TEMPS ARE
EXPECTED TO BE AT OR ABOVE CLIMO NORMS THROUGH THE PERIOD.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE OVER EASTERN CANADA MOVES OFFSHORE TONIGHT.
SCT-BKN CIGS AT 3500-4000 FT OVER SE CT AND EASTERN LONG ISLAND WILL
CONTINUE TO SCATTER OUT THROUGH THIS EVENING. VFR THROUGH THIS
EVENING.
WIDESPREAD STRATUS WILL REDEVELOP TONIGHT. LATEST MAV/LAV GUIDANCE
KEEP THE REGION VFR...WHILE THE LATEST MET GUIDANCE BRINGS CONDS
DOWN TO IFR. WILL LOWER CIGS TO 3000 FT FROM EAST TO WEST STARTING
AT 03Z OVER KGON AND OVER 07Z AT KEWR...AND THEN DOWN TO 1000-1500
FT LATE IN THE EARLY MORNING HOURS.
CONDS GRADUALLY LIFT TO VFR SUNDAY MORNING.
WINDS GENERALLY 10 KT OR LESS...MAINLY OUT OF THE E-SE.
.OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY...
.SUNDAY AFTERNOON...CONDS LIFTING TO VFR EARLY.
.SUNDAY NIGHT-MONDAY NIGHT...IFR IN -RA/FOG AS LOW PRES PASSES
THROUGH THE REGION. W-NW WINDS 15-20 KT WITH 20-25 KT GUSTS MONDAY
NIGHT.
.TUESDAY...VFR. NW WINDS 15-20 KT WITH GUSTS TO 25 KT DURING THE
DAY...THEN WINDS DIMINISH TUESDAY NIGHT.
.WEDNESDAY...VFR.
.THURSDAY...SUB-VFR POSSIBLE IN RAIN/FOG. S WINDS 15-20 KT WITH
20-30 KT GUSTS POSSIBLE.
&&
.MARINE...
SUB-SCA CONDITIONS ON THE WATERS THROUGH SUN NIGHT. UNDERCUT
WAVEWATCH AND NWPS GUIDANCE BY 1-2 FT BASED ON OVER FORECAST
AT BUOYS. THIS WILL KEEP WATER LEVELS JUST BELOW SCA ON THE
OCEAN.
THERE`S THE POTENTIAL FOR GALE FORCE WINDS ON ALL WATERS MON
NIGHT AND TUE AS WINDS STRENGTHEN IN RESPONSE TO DEEPENING LOW
PRES DEPARTING TO THE NORTHEAST AND HIGH PRES BUILDING FROM THE
MIDWEST...COLD ADVECTION AND SHARP PRES RISES. SCA MAY LINGER INTO
TUE NIGHT. BRIEF TRANQUIL CONDS ON WED WITH HIGH PRES OHD MOVING
OFFSHORE. WINDS STRENGTHEN AGAIN WITH SCA POSSIBLE LATE WED NIGHT
BETWEEN THIS STRONG HIGH AND APPROACHING LOW PRES.
&&
.HYDROLOGY...
AROUND A HALF INCH OF RAIN IS POSSIBLE SUN NGT AND MON. ADDITIONAL
RAINFALL IS POSSIBLE FOR THE END OF NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...24/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...24
AVIATION...MPS
MARINE...24/DW
HYDROLOGY...24/DW
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
417 PM EDT SAT MAR 26 2016
.NEAR TERM.../THROUGH SUNDAY/...
THIS AFTERNOON/TONIGHT...DELAYED ONSET OF SHOWERS/STORMS DUE TO
CLOUD COVER AND LINGERING CAP OVER THE AREA. AS WAVE ACROSS THE
EASTERN FL PANHANDLE COAST MOVES NE...WIDESPREAD AREA OF SHOWERS
AND STORMS ACROSS SW GA AND FL PANHANDLE WILL CONTINUE SPREADING
EAST ACROSS THE AREA THE REMAINDER OF THE AFTERNOON INTO THE EARLY
EVE. HIGH-RES HRRR SHOWING MESO-HIGH...ASSOCIATED WITH THE
CONVECTION ACROSS SW GA... WILL BE ACROSS COASTAL SE GA THIS EVE
WITH ADDITIONAL CONVECTION ALONG THE EAST COAST SEABREEZE
SPREADING NORTH. WILL CONTINUE TREND OF RAISING POPS TO
LIKELY/CATEGORICAL THROUGH THE EARLY EVENING...THEN LOWERING TO
CHANCE THE REMAINDER OF THE NIGHT AS THE WAVE AND ASSOCIATED
IMPULSE LIFTS NE. SOME STORMS MAY BE STRONG WITH STRONG WIND
POTENTIAL AND FREQUENT LIGHTNING.
SUNDAY...THE LAST IN A SERIES OF UPPER LEVEL PERTURBATIONS WILL
SLOWLY MOVE OVER THE REGION. THE ELONGATED VORT LOBE COUPLED WITH
UPPER LEVEL DIVERGENCE AND A VERY MOIST AIRMASS WITH FLOW OFF THE
GULF WILL SET THE STAGE FOR WIDESPREAD RAINFALL. WE HAVE MODIFIED
POPS SOMEWHAT AND HAVE CATEGORICAL POPS FOR MAINLY ALL AREAS NORTH
OF THE STATE BORDER WITH LIKELY POPS MOST AREAS SOUTH OF
THERE...EXCEPT CHANCE ACROSS THE FAR SOUTH. SOME STORMS AGAIN MAY
BE STRONG WHICH WILL DEPEND ON HOW MUCH HEATING OCCURS. ANY STORMS
THAT MANAGE TO GET GOING WILL BE POTENTIALLY STRONG WITH WET
MICRO-BURST POTENTIAL AND SPC HAS OUR AREA UNDER A MARGINAL RISK.
CLOUDS AND PRECIP WILL HOLD TEMPS IN THE LOW TO MID 70S IN SE
GA...BUT SOME PARTIAL SUN COULD HELP NUDGE TEMPS INTO THE LOWER
80S ACROSS THE FAR SOUTH.
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
A POTENT SHORTWAVE TROUGH WILL PROGRESS NORTHEASTWARD FROM THE
MID-MISSISSIPPI VALLEY ON SUN EVENING TO NEW ENGLAND BY LATE MON.
THIS FEATURE WILL DRAG A WEAKENING COLD FRONT THROUGH THE
SOUTHEASTERN STATES ON SUN NIGHT AND ACROSS SOUTHEAST GA AND THE
FL PANHANDLE BY LATE MON. SHOWERS AND THUNDERSTORMS WILL LINGER
OVER MUCH OF OUR AREA ON SUN EVENING...WITH THE BEST FORCING
ASSOCIATED WITH SHORTWAVE ENERGY LOCATED OVER SOUTHEAST GA. A FEW
STRONG THUNDERSTORMS COULD LINGER PAST SUNSET TOMORROW
EVENING...WITH SOME DECREASE IN COVERAGE EXPECTED FROM WEST TO
EAST AFTER MIDNIGHT AS A VORTICITY LOBE ONLY SLOWLY MOVES EASTWARD
AND OFFSHORE. A VERY MOIST AIR MASS COULD ALSO PROMOTE FOG
DEVELOPMENT AS THE RAINFALL ENDS DURING THE PREDAWN HOURS ON MON.
LOWS WILL REMAIN IN THE 60S AREA-WIDE AHEAD OF THE APPROACHING
FRONTAL BOUNDARY.
LOW PRESSURE WILL RACE NORTHEASTWARD THROUGH THE EASTERN GREAT
LAKES ON MON...WITH FORCING ALOFT DECREASING LOCALLY AS THE DAY
PROGRESSES AND DRIER AIR ALOFT WORKING INTO OUR REGION FROM THE
WEST AND SOUTHWESTERLY WINDS STRENGTHENING TO 10T-15 MPH AHEAD OF
THE WEAKENING COLD FRONT APPROACHING FROM THE WEST. SOME LOW-
LEVEL CONVERGENCE WILL REMAIN AHEAD OF THE FRONT OVER NORTHEAST
AND NORTH CENTRAL FL...WITH WIDELY SCATTERED SHOWERS AND A FEW
THUNDERSTORMS POSSIBLE SOUTH OF INTERSTATE 10 THROUGH THE
AFTERNOON HOURS. OFFSHORE WINDS AND DECREASING MID AND HIGH CLOUD
COVER WILL BOOST HIGHS INTO THE LOWER 80S ALL THE WAY TO THE
BEACHES.
HIGH PRESSURE WILL BUILD INTO OUR REGION FROM THE NORTHWEST ON MON
NIGHT...WITH NORTHWESTERLY WINDS DEVELOPING IN THE LOW LEVELS
PUSHING THE FRONTAL BOUNDARY INTO CENTRAL FL AND ALLOWING A DRIER
AIR MASS TO GRADUALLY FILTER INTO OUR AREA. LOWS WILL FALL INTO
THE 50S INLAND...RANGING TO THE LOWER 60S AT THE COAST. HIGH
PRESSURE WILL THEN BUILD TO THE NORTH OF OUR REGION ON TUES...WITH
LOW LEVEL WINDS VEERING TO A NORTHEASTERLY DIRECTION BY AFTERNOON.
THE FRONT WILL STALL OVER CENTRAL FL...WITH WIDELY SCATTERED
SHOWERS AND A FEW THUNDERSTORMS POSSIBLY DEVELOPING JUST NORTH
OF THIS BOUNDARY OVER OUR FAR SOUTHERN LOCATIONS. BREEZY ONSHORE
WINDS OVER THE COOL SHELF WATERS WILL KEEP HIGHS IN THE LOW TO MID
70S ALONG THE COAST...RANGING TO NEAR 80 IN THE SUWANNEE VALLEY
AND INLAND NORTH CENTRAL FL. ANY AFTERNOON CONVECTION OVER NORTH
CENTRAL FL WILL QUICKLY DISSIPATE ON TUES EVENING...WITH SOME HIGH
CLOUDINESS MOVING ACROSS OUR AREA DURING THE OVERNIGHT HOURS. LOWS
WILL RANGE FROM THE 50S OVER INLAND SOUTHEAST GA TO THE MID 60S IN
COASTAL NORTHEAST FL...WHERE ONSHORE WINDS WILL PERSIST.
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
A BROAD TROUGH ALOFT OVER THE WESTERN U.S. DURING THE MIDWEEK TIME
FRAME WILL SLOWLY MIGRATE INTO THE EASTERN U.S. BY NEXT WEEKEND.
SURFACE RIDGING CENTERED OVER THE MID-ATLANTIC STATES ON WED WILL
MOVE OFFSHORE BY WED EVENING...WITH WINDS VEERING LOCALLY TO A
SOUTHEASTERLY DIRECTION BY WED AFTERNOON...AND THEN SOUTH TO
SOUTHWESTERLY FOR THURS AND FRI. CONDITIONS WILL MOISTEN ENOUGH
FOR ISOLATED AFTERNOON CONVECTION TO DEVELOP OVER INLAND LOCATIONS
DURING THE AFTERNOON HOURS ON WED...WITH SCATTERED MAINLY DIURNALLY
DRIVEN CONVECTION POSSIBLE ON THURS. HIGHS WED WILL RANGE FROM THE
MID 70S AT THE COAST DUE TO ONSHORE FLOW TO THE LOW/MID 80S
INLAND. ABOVE NORMAL LOWS ARE EXPECTED BEGINNING WED NIGHT...WITH
60S EXPECTED THROUGH FRI NIGHT. HIGHS THURS WILL WARM INTO THE MID
80S INLAND...WITH UPPER 70S AT THE BEACHES.
THERE ARE SIGNIFICANT DIFFERENCES IN THE DETAILS AND TIMING OF THE
NEXT FRONTAL PASSAGE EXPECTED TO OCCUR ON FRI OR SAT. NUMEROUS
SHOWERS AND EMBEDDED THUNDERSTORMS ARE EXPECTED ALONG AND AHEAD OF
AN APPROACHING FRONTAL BOUNDARY...WITH THE 12Z OPERATIONAL GFS
SPEEDING UP THE PASSAGE TO LATE FRI...WHILE THE 12Z OPERATIONAL
ECMWF SUGGESTING A WAVE OF LOW PRESSURE DEVELOPING ALONG THE
BOUNDARY TO OUR WEST ON LATE FRI...AND THUS DELAYING THE PASSAGE
UNTIL SAT. ABOVE NORMAL TEMPS WILL PERSIST AHEAD OF THE
FRONT...WITH HIGHS GENERALLY REACHING THE 80S...WITH A BRIEF
EPISODE OF SIGNIFICANTLY COOLER AND DRIER AIR POSSIBLE IN THE WAKE
OF THE FRONT BY LATE NEXT WEEKEND.
&&
.AVIATION...
THERE HAS BEEN A LULL IN CONVECTION THIS AFTERNOON DUE TO CLOUD
COVER AND LINGERING CAP OVER THE AREA. HOWEVER...LARGE COMPLEX
OF STORMS TO THE WEST WILL CONTINUE TO GRADUALLY MOVE EAST. HIGH-
RES MODELS (HRRR) SHOWING ADDITIONAL STORMS DEVELOPING ALONG THE
EAST COAST SEABREEZE AND MOVING NORTH LATE THIS AFTERNOON INTO THE
EARLY EVE. CONFIDENCE IS LOW ON EXACT TIMING OF ONSET OF
SHOWERS/STORMS DUE TO THE CAP IN THE AREA AND HAVE VCTS IN ALL TAF
SITES FOR NOW BETWEEN 21Z-01Z. WHILE THERE WILL ALSO BE THE
POTENTIAL FOR LOW CLOUDS AND FOG TONIGHT...CONFIDENCE LOW AT THIS
TIME DUE TO EXTENSIVE DEBRIS CLOUDS AND POSSIBLE LINGERING
SHOWERS.
&&
.MARINE...
SOUTH TO SOUTHEAST FLOW AT 10-15 KNOTS WITH SEAS GENERALLY IN THE
2-4 FT RANGE WILL CONTINUE THROUGH SUNDAY WITH NO HEADLINES. WINDS
BECOME SOUTHWEST SUNDAY NIGHT THEN NORTHWEST BEHIND THE NEXT
FRONTAL PASSAGE ON MONDAY ALTHOUGH WINDS SPEEDS AND SEAS STILL
EXPECTED TO REMAIN BELOW ADVISORY LEVELS OVER THE WATERS. HIGH
PRESSURE BUILDS NORTH OF THE REGION AND EXPECT NORTHEAST WINDS TO
DEVELOP ON TUESDAY AND BECOME EAST ON WEDNESDAY WITH AN INCREASE
TO SMALL CRAFT ADVISORY LEVELS POSSIBLE WITH BUILDING SEAS.
RIP CURRENTS:
LOW RISK CONTINUES IN THE WEAK SE/S FLOW WITH BREAKERS OF 2-3 FT
AT THE LOCAL BEACHES.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 64 74 62 81 / 70 90 80 20
SSI 65 73 64 78 / 70 90 80 20
JAX 65 78 65 83 / 80 70 70 30
SGJ 67 76 66 81 / 70 60 60 40
GNV 66 80 67 83 / 80 50 50 40
OCF 68 82 68 83 / 60 50 50 50
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
PETERSON/NELSON/GUILLET
...PREVIOUS EXTENDED FORECAST DISCUSSION...
TUE-SAT...SLIGHT DRYING IS INDICATED TUE AS THE FRONTAL TROUGH DROPS
SOUTH...BUT THE LATEST GFS AND ECMWF SHOW A DISTURBANCE APPROACHING
WHICH WILL NECESSITATE CHANCE POPS. TEMPS ALOFT ARE FORECAST TO BE
QUITE COLD SO CANNOT RULE OUT THUNDER AGAIN TUE AFTERNOON. SURFACE
HIGH MOVING OFF THE COAST TO OUR NORTH WILL PROVIDE AN ONSHORE FLOW
WED. AN OVERALL MORE STABLE ATMOSPHERE IS INDICATED AS WEAK RIDGING
MOVES OVERHEAD. POPS AROUND 20 PERCENT WITH THUNDER CHANCES SHIFTED
WELL INLAND LOOK IN ORDER. LOW LEVEL WINDS ARE FORECAST TO TURN
SOUTHEAST THU AND SOUTH ON FRI. THIS WILL INCREASE MOISTURE AND
SHOULD BRING A SMALL CHANCE FOR AFTERNOON STORMS. HIGHS WILL
CONTINUE A LITTLE ABOVE NORMAL IN THE LOWER-MID 80S. OVERNIGHT LOWS
WILL BE ABOUT 5-10 DEGREES ABOVE NORMAL IN THE MID 60S.
&&
.AVIATION...SCT CIGS AND VSBY INTERRUPTED BY PCPN ALONG WITH SCT
STORMS WITH SOME REDUCTIONS TO MVFR AND BRIEF IFR TONIGHT THROUGH
27/03Z. CONDS BECMG VFR AFT 27/04Z. THERE WILL BE SOME PATCHY GROUND
FOG POSSIBLE IN RAIN AFFECTED AREAS EARLY SAT MNLY FM 27/09Z-27/12Z.
&&
.MARINE...TONIGHT/SUNDAY...WITH THE ATLC RIDGE AXIS LIFTING N OF THE
FORECAST AREA LIGHT ONSHORE WINDS WILL PREVAIL. SEAS AROUND 2 FT
NEAR SHORE AND 3 TO 4 FT WELL OFFSHORE CAN BE EXPECTED. MARINERS
WILL SEE THE PRIMARY THREAT FROM THE COASTAL STORMS VICE PREVAILING
WIND AND SEA STATE WHICH ASIDE FROM STORMS.
SUN NIGHT...NEAR STATIONARY FRONTAL BOUNDARY REMAINING NORTH OF THE
AREA WITH PLENTY OF MOISTURE AROUND AND DISTURBANCES ALOFT. THE HIGH
PRESSURE RIDGING WILL CONTINUE TO WEAKEN AND RETREAT TOWARDS THE
SOUTH AND EAST. OFFSHORE MOVING CONVECTION IN THE EVENING DUE TO SEA
BREEZE COLLISIONS OVER THE MAINLAND AND STORM STEERING FLOW TAKING
REMNANTS OFF OF THE COAST...INTRACOASTAL WATERWAYS AND NEAR SHORE
ATLC WATERS. STORM MOTION TOWARD THE EAST OR ENE AT 20 TO 25 MPH.
WIND GUSTS IN EXCESS OF 35 KTS...TORRENTIAL DOWNPOURS...FREQUENT
LIGHTNING AND SMALL HAIL CONTINUE TO BE THE MAIN THREATS. LOCALLY
HIGHER SEAS INVOF STRONGER STORMS.
SERLY WINDS ALONG THE COAST FROM THE LATE DAY SEA BREEZE WILL VEER
BACK TO SSW IN THE EVENING/OVERNIGHT WITH SPEEDS 10-13 KTS OVER THE
OPEN ATLC. SEAS GENERALLY 2-3 FT NEAR SHORE AND 3-4 FT OFFSHORE.
...PREVIOUS MARINE EXTENDED DISCUSSION...
MON-THU...SURFACE RIDGE AXIS WILL GET NUDGED SOUTH MON AS TAIL END
OF FRONTAL BOUNDARY DROPS IN TO NORTH FLORIDA. WINDS WILL VEER TO
THE SOUTHWEST WITH SPEEDS 10-15 KNOTS. GREATEST CHANCE FOR OFFSHORE
MOVING STORMS IN THE AFTERNOON/EVENING LOOKS TO BE SOUTH OF CAPE
CANAVERAL. THE PRESSURE GRADIENT IS FORECAST TO EASE LATE MON INTO
TUE AS THE FRONTAL TROUGH WEAKENS ACROSS THE WATERS. IT LOOKS DRIER
OVERALL BUT A SLIGHT CHANCE FOR OFFSHORE MOVING STORMS EXISTS TUE
AFTERNOON. HIGH PRESSURE TO THE NORTH IS SHOWN BRIDGING THE OLD
FRONTAL BOUNDARY ON WED WITH WINDS FRESHENING OUT OF THE EAST. SMALL
SHOWER CHANCES EXPECTED BUT MAIN CHANCE FOR STORMS SHOULD BE WELL
INLAND.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 69 83 68 82 / 40 60 60 40
MCO 69 86 70 84 / 40 50 50 40
MLB 70 86 70 84 / 40 30 50 40
VRB 69 86 69 86 / 30 20 40 40
LEE 69 86 70 84 / 40 60 50 40
SFB 68 86 70 83 / 40 60 50 40
ORL 69 86 70 83 / 40 50 50 40
FPR 70 86 68 86 / 30 20 40 50
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...PENDERGRAST
LONG TERM/RADAR....SEDLOCK
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
248 PM CDT SAT MAR 26 2016
.SHORT TERM...(THIS EVENING THROUGH Sunday)
ISSUED AT 216 PM CDT SAT MAR 26 2016
Forecast issues focus on the current changing conditions,
including cold air advection over the area and the advancing upper
shortwave over southwest Colorado at this time. Although
temperatures have increased into the 40s where stratus has mixed
out, little more gain in temperature is expected this afternoon
as north winds/cold advection is discounting insolation. 88D
reflectivity return echos from central CO into Syracuse-Scott City
region, appears to be giving credibility to the last NAM runs and
this solution was generally followed to adjust short term into
tonight POP forecasts. QPF on the order of a tenth of an inch is
possible across the southern counties laster tonight in the
overnight. The convective allowing models` reflectivity output
has suggested a corridor of better likely rain/snow developments
across the extreme southeast, and the area of the wildfire during
the middle of the overnight.
Sunday should bring less cloud cover and lighter north/westerly
winds owing to the broad high pressure over the plains and
mountain region. Highs should rebound to near 60 degrees based on
model consensus.
.LONG TERM...(Sunday NIGHT THROUGH Saturday)
ISSUED AT 216 PM CDT SAT MAR 26 2016
Slightly more mild lows are expected by monday morning. A mid
level ridge develops behind the exiting system heading into early
next week. Monday through Wednesday present at minimum elevated
fire danger environments, and potential red flag set ups, with
Tuesday being the warmest and most likely as highs soar toward
the 80s. The next pattern shift/cooldown look like late Wednesday
into Thursday.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Sunday AFTERNOON)
ISSUED AT 109 PM CDT SAT MAR 26 2016
Immediate concern was on the duration of a narrow band of MVFR
stratus located just behind the surface cold front, affecting HYS
and DDC. Models like HRRR and short term blends do not hold on to
the cover long as drier air/downslope overcomes the area, however
they seem to be having problems with the stratus farther
northwest. TAFs may need to be adjusted to have stratus much
longer through the first 6 hours if the coverage doesn`t start
trending downward. Rain or snow showers are possible at DDC/GCK
after 06 UTC as a sharp upper wave rotates into Oklahoma.
Afternoon terminal amendments are likely.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 29 58 35 72 / 30 10 0 0
GCK 26 60 33 77 / 20 0 0 0
EHA 25 58 35 76 / 60 0 0 0
LBL 29 59 36 76 / 50 0 0 0
HYS 26 61 33 72 / 10 10 0 0
P28 32 59 34 68 / 70 10 0 0
&&
.DDC Watches/Warnings/Advisories...NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Russell
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
120 PM CDT SAT MAR 26 2016
...UPDATED AVIATION TERMINALS...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 200 AM CDT SAT MAR 26 2016
Water vapor imagery shows an trough upstream. This feature will swing
through the region late tonight. Models continue the QPF trend of shifting
the heavier precipitation axis farther south. Have the highest pops
along the Oklahoma border. A tenth or two is possible near the state
line. As with the lower precipitation amounts comes lower snow
amounts. Models are trending warmer too with the thermodynamics,
so that will cut down snow totals as well. Have around half an
inch to one inch along the state line and the surrounding
counties. Otherwise, today will be colder in the wake of a front
with highs in the 50s. Lows will be mainly in the 20s, save south-
central Kansas were readings will be a few degrees warmer.
.LONG TERM...(Sunday THROUGH Friday)
ISSUED AT 200 AM CDT SAT MAR 26 2016
The precip will quickly taper off to the south by early Sunday afternoon.
There will be weak southwesterly flow, and thus highs should moderate
to around 60 degrees. On Monday, the warm air advection strengthens
significantly with a downslope plume developing. Upper 70s to around
80 degrees will be possible in the western zones. On Tuesday, a lee
low deepens with a continued waa pattern. The warm plume advects east
and temperatures will respond by topping out a few degrees higher. Have
pops capped as it seems the atmosphere will be capped as well Tuesday
evening. A slight better chance for thunderstorms across south-central
Kansas is possible Wednesday night as lift associated with a passing
wave/front increases. The front looks fairly strong so most of the convection
could remain out of the area entirely. There may be light showers in
the wake up north. During this period, there probably will be fire weather
concerns west of the front/dryline. Beyond this, a dry forecast is expected
with moderating temperatures.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Sunday AFTERNOON)
ISSUED AT 109 PM CDT SAT MAR 26 2016
Immediate concern was on the duration of a narrow band of MVFR
stratus located just behind the surface cold front, affecting HYS
and DDC. Models like HRRR and short term blends do not hold on to
the cover long as drier air/downslope overcomes the area, however
they seem to be having problems with the stratus farther
northwest. TAFs may need to be adjusted to have stratus much
longer through the first 6 hours if the coverage doesn`t start
trending downward. Rain ior snow showers are possible at DDC/GCK
after 06 UTC as a sharp upper wave rotates into Oklahoma.
Afternoon terminal amendments are likely.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 29 58 35 72 / 30 10 0 0
GCK 26 60 33 77 / 20 0 0 0
EHA 25 58 35 76 / 60 0 0 0
LBL 29 59 36 76 / 50 0 0 0
HYS 26 61 33 72 / 10 10 0 0
P28 32 59 34 68 / 70 10 0 0
&&
.DDC Watches/Warnings/Advisories...NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Sugden
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS CARIBOU ME
336 PM EDT SAT MAR 26 2016
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE AREA THIS EVENING AND WILL
SLOWLY MOVE EAST INTO THE MARITIMES LATER TONIGHT INTO SUNDAY.
LOW PRESSURE WILL CROSS THE REGION LATE MONDAY AND MONDAY EVENING
AND WILL BE FOLLOWED BY HIGH PRESSURE FOR THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
CHALLENGE THIS TERM WILL BE CLOUDS AND FOG OR DRIZZLE POTENTIAL.
SKIES WILL START OUT CLEAR THIS EVENING AND THEN MODEL SOUNDINGS
INDICATE POTENTIAL SOME LLVL MOISTURE GETTING TRAPPED UNDER THE
INVERSION LATER TONIGHT W/SOME STRATUS DEVELOPING. BLYR WINDS GO
SE WHILE THE FLOW ALOFT IS MORE SSW WHICH IS A GOOD SETUP FOR THIS
TO TAKE PLACE. BUFKIT DATA ALSO SHOWING FOG OR DRIZZLE POTENTIAL
W/THE HRRR 3KM AND WRF SHOWING SOME LIGHT RETURNS. AFTER FURTHER
COLLABORATION W/GYX, DECIDED TO CARRY PATCHY FOG AND LOW CLOUDS
OVERNIGHT INTO EASTER SUNDAY MORNING. TEMPS WILL DROP OFF TONIGHT
AFTER SUNSET W/DRIER AIR IN PLACE AS READINGS WILL BE DOWN TO MID
TO UPPER TEENS ACROSS THE NORTH AND WEST W/LOW TO MID 20S CENTRAL
AND DOWNEAST. LOW CLOUDS SHOULD CAP A FURTHER DROP IN THE TEMPS.
LOW CLOUDS AND FOG WILL HANG ON FOR A WHILE DURING THE MORNING ON
EASTER SUNDAY AND THEN THERE IS POTENTIAL FOR CLOUDS TO BREAK UP
FOR A TIME ESPECIALLY ACROSS DOWNEAST THE COAST AS SSE WINDS PICK
UP TO AROUND 10 MPH. THIS WILL ALSO CUT DOWN ON TEMPS RISING DUE
TO THE FLOW OFF THE COLDER GULF OF MAINE WATERS. AS A MATTER OF
FACT, NORTHERN AREAS COULD BE A TAD WARMER ESPECIALLY IF SOME SUN
APPEARS. ALL THIS DESPITE SFC HIGH PRES OVER THE REGION.
THEREFORE, DECIDED TO HANG ON TO CLOUDS INTO THE AFTERNOON.
DAYTIME TEMPS WILL RUN NEAR NORMAL FOR LATE MARCH.
ANOTHER INTERESTING THING IS THE POTENTIAL FOR DRIZZLE TO SET UP
LATE IN THE DAY AS EVIDENT FROM THE NAM/GFS SOUNDINGS AND BUFKIT
PROFILES. A MID LEVEL DISTURBANCE IS FORECAST TO SLIDE ACROSS THE
REGION AIDING IN THE DRIZZLE POTENTIAL. THE BEST POTENTIAL FOR THE
DRIZZLE LOOKS TO BE ACROSS THE EASTERN 1/2 OF THE CWA WHERE THE
BEST LLVL CONVERGENCE WILL BE SITUATED. CARRIED PATCHY WORDING FOR
NOW. LATER SHIFTS CAN ASSESS FURTHER W/THE LATER GUIDANCE.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
SIGNIFICANT WEATHER SYSTEM MONDAY THROUGH EARLY TUESDAY.
FIRST CONCERN BEFORE THE STORM REALLY MOVES IN IS THE POTENTIAL
FOR FREEZING DRIZZLE SUNDAY NIGHT. MODEL SOUNDINGS INDICATESHALLOW
LAYER OF MOISTURE AS ONSHORE FLOW DEVELOPS AHEAD OF THE NEXT
SYSTEM. LOOKS JUST COLD ENOUGH FOR FREEZING DRIZZLE WITH MANY
AREAS JUST BELOW FREEZING AT THE SURFACE, BUT THE MOISTURE NOT
BEING DEEP ENOUGH TO TAP A LEVEL COLD ENOUGH FOR ICE CRYSTAL
FORMATION.
THEN THE FOCUS TURNS TOWARD A POTENT SYSTEM BEGINNING MONDAY.
MODELS STILL HAVING SOME ISSUES WITH THE STORM. MAIN ISSUE IS HOW
FAST THE PRIMARY LOW CENTER SHIFTS FROM BEING THE ONE WEST OF
QUEBEC CITY TO THE ONE IN THE GULF OF MAINE. THE FASTER THE
TRANSFER OF ENERGY OCCURS, THE QUICKER OUR CHANGEOVER TO SNOW.
GFS HAS BEEN SLOWER ON THE TRANSFER, ALTHOUGH ITS ENSEMBLE
MEMBERS SEEM TO BE FASTER ON THE TRANSFER. ECMWF, CANADIAN, AND
NAM ARE A BIT FASTER ON THE TRANSFER, AND I TEND TO FAVOR A
FASTER TRANSFER OF ENERGY WHICH WOULD RESULT IN A FASTER
CHANGEOVER TO SNOW MONDAY EVENING.
BEST GUESS FORECAST AT THIS TIME IS FOR MOSTLY RAIN DURING THE DAY
ON MONDAY, ALTHOUGH EXTREME NORTHERN MAINE MAY MIX AT TIMES. THEN
A CHANGEOVER TO A MIX AND EVENTUALLY TO SNOW MAINLY FOR NORTHERN
MAINE MONDAY NIGHT AND PERHAPS CONTINUING INTO TUESDAY MORNING.
WINDY AND COLDER TUESDAY. FIRST GUESS AT SNOW AMOUNTS IS FOR 3 TO
6 INCHES OVER THE NORTH, THE HIGHEST AMOUNTS THE FURTHER NORTH YOU
GO. THESE AMOUNTS ARE OF COURSE SUBJECT TO CHANGE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE ALOFT BUILDS ALONG THE EAST COAST DURING THE MIDDLE OF
NEXT WEEK. AFTER NEAR NORMAL TEMPERATURES ON WEDNESDAY...MUCH
WARMER AIR PUSHES INTO THE REGION ON THURSDAY AHEAD OF A STRONG COLD
FRONT.
SHOWERS WILL PUSH THROUGH THE STATE LATE THURSDAY AFTERNOON AND
THURSDAY NIGHT. THE AIR BEHIND THE FRONT IS NOT MUCH COOLER...
THEREFORE MUCH ABOVE NORMAL TEMPERATURES ARE EXPECTED ON FRIDAY.
COMPUTER MODELS CONTINUE TO ADVERTISE A VERY DEEP UPPER TROUGH
CENTERED OVER HUDSON BAY AND THE GREAT LAKES NEXT WEEKEND. SATURDAY
IS FORECAST TO BE CLOUDY...COOLER WITH INSTABILITY SHOWERS.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
NEAR TERM: VFR THIS EVENING FOR ALL TERMINALS W/MVFR AND POSSIBLE
IFR CONDITIONS FOR CIGS AND VSBYS. THE MVFR/IFR CONDITIONS COULD
HANG ON THROUGH MID TO LATE MORNING.
SHORT TERM: IFR CEILINGS EXPECTED TO DEVELOP SUNDAY NIGHT WITH
PERHAPS SOME FREEZING DRIZZLE. WIDESPREAD IFR CONTINUING MONDAY
AND MONDAY NIGHT AS MORE SIGNIFICANT PRECIPITATION MOVES INTO THE
ENTIRE AREA, GENERALLY FALLING AS RAIN MONDAY THEN CHANGING TO
RAIN/SNOW OR SNOW MONDAY NIGHT. IMPROVING TO VFR AGAIN BY THE END
OF THE DAY TUESDAY, BUT WINDY.
&&
.MARINE...
NEAR TERM: SCA CANCELLED W/WINDS AND SEAS DOWN TO 15 KTS AND 4 FT
RESPECTIVELY. THESE CONDITIONS SHOULD HOLD RIGHT INTO EASTER
SUNDAY.
SHORT TERM: PERHAPS SOME MIN LEVEL SMALL CRAFT WINDS AND SEAS LATE
MONDAY. STRONGER OFFSHORE GALE FORCE WINDS POSSIBLE TUESDAY AS THE
COLDER AIR MOVES IN.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...FOISY
LONG TERM...OKULSKI
AVIATION...HEWITT/FOISY
MARINE...HEWITT/FOISY
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
351 PM CDT SAT MAR 26 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 345 PM CDT SAT MAR 26 2016
FRONT HAS STALLED OUT THIS AFTERNOON FROM FAIRMONT...TO THE TWIN
CITIES AND HAYWARD. THIS FRONT HAS LAID DOWN THE TRACKS FOR A SFC
LOW ASSOCIATED WITH A STRONG WAVE ON WATER VAPOR IMAGERY QUICKLY
MOVING NORTH ALONG THE IA/NEB BORDER. MODELS HAVE COME INTO GOOD
AGREEMENT ON A DECENT DEFORMATION BAND SETTING UP TO THE NW SIDE OF
THE SFC LOW...WITH A BAND OF QPF NEAR A HALF INCH EXPECTED FROM
REDWOOD FALLS TO HINKLEY. AMOUNTS MORE AROUND A QUARTER INCH ARE
EXPECTED FROM SOUTH CENTRAL INTO EAST CENTRAL MN AND WESTERN
WI...WITH AMOUNTS QUICKLY GOING TO ZERO NOT FAR FROM ALEXANDRIA.
STILL HOLDING OFF ON ISSUING ANY ADVY...AS 12Z MODELS ALONG WITH
HOURLY/3 HOURLY UPDATING CAMS ARE NOT PUTTING AS MUCH QPF BACK TO
THE WEST IN THE COLD AIR AS THEY HAD BEEN PREVIOUSLY. IN
ADDITION...TEMPERATURES HAVE WARMED INTO THE UPPER 30S OUT IN WRN
MN...WITH THE MAX WET BULB ZERO LINE AT 19Z EXTENDING UP ALONG THE
MN/DAKOTAS BORDER TO THE NORTH OF FARGO. THESE WARMER TEMPERATURES
OUT THE GATE WILL DELAY THE TRANSITION TO SNOW...ADD IN LESS QPF
GETTING INTO THE COLD AIR...AND ITS TOUGH TO SEE HOW WE SEE MUCH
MORE THAN 1 OR 2 INCHES OF ACCUMULATION FROM WEST CENTRAL THROUGH
CENTRAL MINNESOTA.
THE THEME FOR SUNDAY WILL BE IMPROVING CONDITIONS. RAIN WILL QUICKLY
CLEAR THE WI COUNTIES DURING THE FIRST HALF OF THE MORNING...WHILE
CLEARING SKIES WILL BE WORKING ACROSS MINNESOTA. BY THE
AFTERNOON...THE TWIN CITIES WILL HAVE MOSTLY SUNNY SKIES...WITH
SIMILAR SKY CONDITIONS NOT MAKING IT TO EAU CLAIRE UNTIL MID TO LATE
AFTERNOON. THOUGH WE WILL BE SEEING SUNNY SKIES...925-850 TEMPS
BETWEEN 0C AND 4C...WILL KEEP HIGHS AROUND 50.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 PM CDT SAT MAR 26 2016
THERE IS A CLASSIC HIGH WAVE NUMBER SPRING PATTERN ACROSS THE
NORTHERN HEMISPHERE...AND ACROSS NORTH AMERICA...THE FLOW IS
HIGHLY AMPLIFIED. THE RESULT WILL BE BIG TEMPERATURE SWINGS AND
NEAR TO ABOVE NORMAL PRECIPITATION OVER THE NEXT 7-10 DAYS.
SUNDAY NIGHT THROUGH TUESDAY WILL FEATURE ABOVE NORMAL
TEMPERATURES AS THE LOW LEVEL FLOW BACKS FROM THE NORTHWEST TO THE
WEST-SOUTHWEST. EVEN WITH MODEST MIXING...HIGHS IN THE 50S ARE
LIKELY AND 60 IS NOT OUT OF THE QUESTION. THIS ESPECIALLY TRUE ON
TUESDAY IF THE RAIN AND CLOUD COVER END UP REMAINING
NORTH...HOWEVER...THE WARM FRONT WILL BE IN THE AREA SO CLOUDS ARE
MORE LIKELY THAN SUNSHINE. RAIN IS EXPECTED WHEN THE FRONTAL
BOUNDARY COMES THROUGH...BUT THE HEAVIEST RAIN LOOKS SOUTH AND
EAST OF THE FORECAST AREA. THE 12Z GFS IS WEAKER WITH THE SURFACE
CYCLONE AND IS TRENDING A LITTLE CLOSER TO THE ECMWF NOW. THIS
MEANS THE THUNDER CHANCE IS LOWER ON WEDNESDAY WITH THE
INSTABILITY SOUTH OF MN/WI. THE ECMWF HANGS THE FRONT BACK THU-
FRI AND MN/WI ENDS UP WITH SNOW AS A LOW FORMS ALONG THE BOUNDARY.
THIS IS A NEW DEVELOPMENT WITTHE ECMWF AND WE WILL NEED TO SEE A
COUPLE MORE RUNS WITH A CONSISTENT MESSAGE TO CONSIDER THIS
SOLUTION. THAT BEING SAID...THE 12Z GEM SHOWS A SIMILAR SOLUTION.
FIRST WEEK OF APRIL LOOKS VERY COLD. THIS HAS BEEN A CONSISTENT
PATTERN CHANGE THE PAST TWO DAYS IN THE OPERATIONAL AND ENSEMBLE
GUIDANCE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 110 PM CDT SAT MAR 26 2016
FRONT THIS AFTERNOON HAS STALLED OUT FROM FAIRMONT...TO THE TWIN
CITIES AND ON TO HAYWARD WI. SFC LOW DOWN NEAR OMAHA AT 18Z WILL
FOLLOW THIS FRONT NORTH TONIGHT. LARGE SHIELD OF PRECIP IS ALSO
HEADING THIS WAY...WITH TIMING OF BRINGING IT IN TO TERMINALS
BASED ON A HRRR/HOPWRF BLEND. LIFR/IFR CONDITIONS DOMINATE THE
SCENE ALONG THE IA/NEB BORDER...AND EXPECT THE SAME HERE. ONLY
TERMINAL THAT IS QUESTIONABLE ABOUT GETTING PRECIP IS AXN...WHO
WILL BE NEAR THE NW EDGE OF THE PRECIP. IF AXN DOES SEE
PRECIP...-SN WILL LIKELY END UP BEING THE PRIMARY P-TYPE. EVERYONE
ELSE LOOKS TO REMAIN WARM ENOUGH FOR RAIN...EXCEPT FOR A BRIEF
PERIOD OF -SN AT STC AS THE PRECIP IS MOVING OUT. NOT FAR BEHIND
THE PRECIP WILL BE CLEARING CONDITIONS AS WELL.
KMSP...LOW CONFIDENCE ON WHEN MVFR CIGS WILL MOVE IN. CURRENT TAF
SIMILAR TO GFSLAMP TIMING...THOUGH THE HRRR SAYS MSP STAYS VFR
UNTIL THE MAIN PRECIP SHIELD GETS HERE AROUND 3Z. ONCE THE MAIN
BATCH OF PRECIP GETS HERE...EXPECT CONDITIONS TO RAPIDLY
DETERIORATE TO IFR. ONCE THAT PRECIP GETS HERE...WILL HAVE
SEVERAL HOURS OF CONTINUOUS RAIN...WITH END TIME LOOKING TO COME
BETWEEN 11Z AND 13Z. EXPECT CIGS TO REMAIN BELOW 017 UNTIL WE
CLEAR...WHICH LOOKS TO OCCUR RIGHT AROUND 18Z FROM BOTH THE GFS
AND NAM.
/OUTLOOK FOR KMSP/
MON...VFR. WINDS VARIABLE BCMG ENE 5 KTS.
TUE...VFR CHC -RA LATE. WINDS SE 10-15 KTS.
WED...MVFR. SHRA LIKELY WITH TSRA POSS. WINDS S 10-15 BCMG NW.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
110 PM CDT SAT MAR 26 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM CDT SAT MAR 26 2016
A FEW SHOWERS...MIXED WITH SNOW SHOWERS IN WC/CENTRAL MN EARLY TODAY
WILL GIVE AWAY TO A MUCH WETTER PERIOD BY THE MID/LATE AFTN AS A
POTENT SHORT WAVE MOVES NORTHEAST ACROSS KANSAS/EASTERN NEBRASKA AND
INTO NORTHERN IOWA BY EARLY THIS EVENING.
CURRENT REGIONAL RADAR/SATELLITE IMAGERY INDICATED THIS SHORT WAVE
ALREADY DEVELOPING IN CENTRAL KANSAS. MODELS HAVE COME TOGETHER OVER
THE PAST TWO RUNS TO INDICATE A HIGH PROBABILITY OF A PERIOD OF
WIDESPREAD SHRA/RAIN MOVING INTO SW/SC MN BY EARLY AFTN...AND ACROSS
THE REST OF SOUTHERN/CENTRAL MN AND INTO WC WI BY THE EARLY EVENING.
CURRENT POPS/WX REFLECT THIS CHANGE FROM HIGH CHANCE POPS EARLY...TO
CATEGORICAL BY THE AFTN/EVENING FROM SW TO NE ACROSS MPX CWA.
BASED ON THE MID LEVEL CIRCULATION/SFC FEATURES AND DEFORMATION ZONE
AXIS OVER THE NEXT 24-36 HRS...HIGHEST QPF AMTS WILL BE FROM REDWOOD
FALLS...NORTHEAST TO ST. CLOUD AND MORA. THIS IS SLIGHTLY NW OF
PREVIOUS FORECASTS OF QPF AMTS AND I AM CONCERN WITH SNOWFALL AMTS
IF COLDER AIR ARRIVES EARLIER. THERE IS A MORE PRONOUNCED
DEFORMATION ZONE THEN IN PREVIOUS MODEL RUNS OF THE GFS/EC/GEM. THIS
DEFORMATION ZONE AND THE ADDED AFFECT OF A STRONGER SHORT WAVE...MAY
LEAD TO A BETTER PROBABILITY OF ACCUMULATING SNOWFALL ON THE BACK
EDGE OF THIS SYSTEM LATE TONIGHT. CURRENT QPF AMTS AND ASSOCIATED
SNOWFALL ACCUMULATION HAS NEARLY 4 INCHES IN FAR YELLOW MEDICINE
COUNTY NEAR CANBY. WITH A SWATH OF 1-2 INCHES FROM ALEXANDRIA TO
LITTLE FALLS AND NORTH OF MORA. THERE IS A SMALL AREA OF 3 INCHES
NORTH OF ONAMIA WHICH SEEMS REASONABLE BASED ON THE CURRENT LOCATION
OF THE DEFORMATION ZONE AND SFC LOW TRACK. ANY DEVIATION TO THE
TRACK OF THESE FEATURES AND THE ADDED AFFECT OF COLDER AIR...MAY
LEAD TO A CONSIDERABLE ERROR IN SNOWFALL AMTS. THE ONLY PROBLEM FOR
6+ INCHES IS THE WARMER GROUND AND THE ADDED AFFECT OF RAIN BEFORE
THE TRANSITION TO SNOW.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 355 AM CDT SAT MAR 26 2016
A TASTE OF THE CHAOS SPRINGTIME WEATHER CAN BRING IS EXPECTED IN
THE LONG TERM FORECAST PERIOD...WITH EVERYTHING FROM
THUNDERSTORMS...TO SNOW...TO TEMPERATURE SWINGS MAKING AN
APPEARANCE AT SOME POINT.
SUNDAY WILL BRING LINGERING LIGHT RAIN AND SNOW ACROSS WEST
CENTRAL WISCONSIN DURING THE MORNING...WITH CLEARING SKIES FROM
WEST TO EAST DURING THE AFTERNOON. TEMPS WILL TOP OUT GENERALLY
IN THE 40 TO 50 DEGREE RANGE...WHICH IS NEAR TO SLIGHTLY ABOVE
NORMAL FOR THE END OF MARCH.
MONDAY WE WILL START TO SEE MODERATING TEMPERATURES AS HEIGHTS
BUILD DOWNSTREAM OF AN AMPLIFYING WESTERN CONUS CLOSED LOW. EXPECT
TO MIX CLOSE TO 850MB...WHICH SHOULD TRANSLATE TO HIGHS IN THE
50S. RIDGING BUILDS FURTHER ON TUESDAY AND WE GAIN THE ADDED
INFLUENCE OF THE A 990MB TROUGH NOSING INTO THE NORTHERN PLAINS.
TEMPERATURES SHOULD RESPOND ACCORDINGLY...WITH HIGHS IN THE MID
50S TO LOWER 60S BECOMING COMMON...DESPITE THE INCREASING CLOUD
COVER AND POTENTIAL FOR A FEW WARM AIR/MOISTURE ADVECTION SHOWERS
DEVELOPING DURING THE AFTERNOON.
MODELS ARE STILL STRUGGLING TO RESOLVE THE LOW TRACK ON
WEDNESDAY...WITH THE GFS BEING THE MOST COMPACT AND THUS IN FAVOR
OF CONVECTIVE /THUNDERSTORM/ DEVELOPMENT LOCALLY. THE ECMWF IS
WEAKER AND FARTHER SOUTHEAST WITH THE SURFACE LOW
TRACK...KEEPING US OUT OF THE WARM SECTOR AND MORE STABLE. EITHER
SOLUTION HAS US PRETTY WET...SO HIGH POPS ARE WARRANTED...BUT
CONFIDENCE ON THUNDERSTORMS IS LOWER. HAVE INCLUDED A MENTION OF
THUNDER...BUT CURRENTLY THINK THE SEVERE THREAT WOULD LIE MORE TO
THE SOUTH/EAST.
THE LAST VESTIGES OF THE MID/UPPER TROUGH PASS OVERHEAD ON
THURSDAY AND FRIDAY...SO THE POTENTIAL FOR SPOTTY LIGHT RAIN/SNOW
WARRANTS A 20-30 POP MENTION. TEMPERATURES WILL RETREAT BACK
TOWARD NORMAL...BEFORE WHAT IS LOOKING TO BE A VERY COLD START TO
APRIL. BOTH GFS AND ECMWF NOW FORECAST H85 TEMPS OF -20C TO -25C
FOR NEXT SATURDAY. IF THE GFS HAS ITS WAY...WE COULD BE LOOKING AT
NEAR RECORD LOW HIGH TEMPS FOR NEXT WEEKEND...
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 110 PM CDT SAT MAR 26 2016
FRONT THIS AFTERNOON HAS STALLED OUT FROM FAIRMONT...TO THE TWIN
CITIES AND ON TO HAYWARD WI. SFC LOW DOWN NEAR OMAHA AT 18Z WILL
FOLLOW THIS FRONT NORTH TONIGHT. LARGE SHIELD OF PRECIP IS ALSO
HEADING THIS WAY...WITH TIMING OF BRINGING IT IN TO TERMINALS
BASED ON A HRRR/HOPWRF BLEND. LIFR/IFR CONDITIONS DOMINATE THE
SCENE ALONG THE IA/NEB BORDER...AND EXPECT THE SAME HERE. ONLY
TERMINAL THAT IS QUESTIONABLE ABOUT GETTING PRECIP IS AXN...WHO
WILL BE NEAR THE NW EDGE OF THE PRECIP. IF AXN DOES SEE
PRECIP...-SN WILL LIKELY END UP BEING THE PRIMARY P-TYPE. EVERYONE
ELSE LOOKS TO REMAIN WARM ENOUGH FOR RAIN...EXCEPT FOR A BRIEF
PERIOD OF -SN AT STC AS THE PRECIP IS MOVING OUT. NOT FAR BEHIND
THE PRECIP WILL BE CLEARING CONDITIONS AS WELL.
KMSP...LOW CONFIDENCE ON WHEN MVFR CIGS WILL MOVE IN. CURRENT TAF
SIMILAR TO GFSLAMP TIMING...THOUGH THE HRRR SAYS MSP STAYS VFR
UNTIL THE MAIN PRECIP SHIELD GETS HERE AROUND 3Z. ONCE THE MAIN
BATCH OF PRECIP GETS HERE...EXPECT CONDITIONS TO RAPIDLY
DETERIORATE TO IFR. ONCE THAT PRECIP GETS HERE...WILL HAVE
SEVERAL HOURS OF CONTINUOUS RAIN...WITH END TIME LOOKING TO COME
BETWEEN 11Z AND 13Z. EXPECT CIGS TO REMAIN BELOW 017 UNTIL WE
CLEAR...WHICH LOOKS TO OCCUR RIGHT AROUND 18Z FROM BOTH THE GFS
AND NAM.
/OUTLOOK FOR KMSP/
MON...VFR. WINDS VARIABLE BCMG ENE 5 KTS.
TUE...VFR CHC -RA LATE. WINDS SE 10-15 KTS.
WED...MVFR. SHRA LIKELY WITH TSRA POSS. WINDS S 10-15 BCMG NW.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...LS
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
340 PM CDT SAT MAR 26 2016
.SYNOPSIS...
ISSUED AT 340 PM CDT SAT MAR 26 2016
H5 ANALYSIS FROM EARLIER THIS MORNING HAD A TROUGH OF LOW
PRESSURE ACROSS THE CENTRAL CONUS WITH A CLOSED CIRCULATION OVER THE
WESTERN SANDHILLS OF NEBRASKA. A SECONDARY LOW WAS NOTED OVER
CENTRAL UTAH. WEST OF THE TROUGH...RIDGING EXTENDED UP THE WEST
COAST OF THE CONUS INTO NRN BRITISH COLUMBIA. EAST OF THE
TROUGH....SWRLY FLOW ALOFT EXTENDED EAST INTO THE WESTERN ATLANTIC.
AT THE SURFACE...A COLD FRONT EXTENDED FROM FAR WESTERN IOWA...INTO
FAR SERN NEBRASKA AND EASTERN KANSAS. BREEZY NORTHWESTERLY WINDS
WERE PRESENT WEST OF THE FRONT. TEMPERATURES WERE GENERALLY IN THE
UPPER 20S TO LOWER 30S UNDER A THICK VEIL OF CLOUD COVER. CONDITIONS
ACROSS THE FORECAST AREA WERE DRY AS SNOW AND RAIN WAS JUST OFF TO
THE EAST OF THE AREA...FROM NORFOLK SE TO OMAHA AND FALLS CITY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM CDT SAT MAR 26 2016
MAIN FORECAST CHALLENGE THROUGH SUNDAY IS TEMPERATURE. A SLOW MOVING
AREA OF LOW PRESSURE HAS RESULTED IN A STUBBORN STRATUS DECK AND
BRISK NORTH WINDS...LEADING TO COLDER HIGHS THAN EXPECTED TODAY.
LIGHT SNOW AND FLURRIES WERE ALSO REPORTED ACROSS PARTS OF THE AREA.
THIS EVENING AND TONIGHT... KEPT A SCHC MENTION OF LIGHT SNOW ACROSS
EASTERN BOYD... HOLT... AND WHEELER COUNTIES THROUGH EARLY EVENING.
PERSISTENT SNOW HAS FALLEN JUST EAST OF THE CWA TODAY WITH SOME
LIGHTER SNOW BACKING UP INTO AREAS EAST OF U.S. HIGHWAY 281. SLOWED
THE CLEARING A COUPLE HOURS ACROSS THE WEST... BUT RECENT TRENDS IN
THE VISIBLE SATELLITE AND HI RES MODELS SUGGEST IT WILL OCCUR LATE
AFTERNOON AND EARLY EVENING. NAM AND RAP FORECAST SOUNDINGS INDICATE
SUBSTANTIAL DRYING IN THE MID LEVELS TONIGHT AND LOW LEVEL LIFT
DISAPPEARING AFTER SUNSET. AN 850HPA RIDGE SLOWLY BUILDS
OVERNIGHT... HELPING TO WEAKEN THE FLOW. WITH OVERALL SUBSIDENCE AND
LIGHT WINDS OVERNIGHT... THE BOUNDARY LAYER SHOULD DECOUPLE AND LEAD
TO COOLER MIN TEMPS. LOWERED A DEGREE OR SO ACROSS THE AREA... WHICH
FOLLOWS MAV AND MET GUIDANCE CLOSELY.
SUNDAY... RIDGES AT 500HPA AND 850HPA CONTINUE TO BUILD ACROSS THE
ROCKIES WITH A LULL IN THE UPPER JET. ALL MODELS SHOWING DECENT WAA
WITH H85 TEMPS AT KLBF RISING FROM AROUND 0C AT 12Z TO 7C AT 00Z.
TEMPS APPROACH 8C IN THE PANHANDLE BUT STAY AROUND 3C FAR NORTH
CENTRAL. A DOWNSLOPE REGIME WILL AID IN WARMING AND DRYING ACROSS
THE REGION. GIVEN MIXING TO 750HPA PER NAM SOUNDINGS... PREVIOUS
FORECAST HIGHS NEAR 60F SEEM REASONABLE SO MADE LITTLE CHANGE. THE
HIGHS ALSO AGREE WITH MOS GUIDANCE. DESPITE LOW RH IN THE
AFTERNOON... NEAR 20 PERCENT FOR MANY AREAS WEST OF HWY 83... WIND
WILL NOT SUPPORT SUBSTANTIAL FIRE WEATHER CONCERNS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM CDT SAT MAR 26 2016
MID RANGE...SUNDAY NIGHT THROUGH TUESDAY...LOW AMPLITUDE
RIDGING WILL BUILD INTO THE CENTRAL PLAINS BEGINNING SUNDAY NIGHT
AND WILL OFFER UP SOME DRY AND TRANQUIL CONDS OVER THE NEXT 24 TO 30
HRS. OVERNIGHT LOWS SUNDAY NIGHT WILL BE SEASONAL IN THE MID TO
UPPER 20S...WHILE HIGHS MONDAY WILL BE IN THE UPPER 60S TO AROUND
70. ON MONDAY NIGHT...THE RIDGE WILL BEGIN TO TRANSITION EAST AS A
CLOSED LOW AND TROUGH OF LOW PRESSURE PUSHES INTO NRN UTAH AND SWRN
WYOMING. DOWNSTREAM OF THE TROUGH...STRONG MID LEVEL WAA IN
ASSOCIATION WITH A LEAD SHORTWAVE...WILL LIFT ACROSS CENTRAL AND
EASTERN NEBRASKA. BOTH THE NAM AND GFS SOLNS INDICATE SOME MEAGER
MOISTURE RETURN IN THE EASTERN THIRD OF THE FORECAST AREA OVERNIGHT
TUESDAY NIGHT. DECIDED TO INTRODUCE SOME SLIGHT CHANCE POPS IN THE
FAR EASTERN CWA LATE MONDAY NIGHT AS THE GFS...NAM AND ECMWF ALL
LIFT A DECENT AREA OF MID LEVEL WAA ACROSS THE EASTERN HALF OF
NEBRASKA OVERNIGHT. THE THREAT FOR PCPN WILL END BRIEFLY ACROSS THE
EAST TUESDAY MORNING. BY TUESDAY AFTERNOON...A LOW LEVEL THERMAL
RIDGE WILL PUSH INTO SWRN NEBRASKA. ON THE EASTERN PERIPHERY OF THE
RIDGE...LOW LEVEL MOISTURE WILL BEGIN TO PUSH INTO THE EASTERN HALF
OF THE FORECAST AREA...WITH AFTERNOON DEW POINTS REACHING 45 TO 50
DEGREES EAST OF HIGHWAY 83. WITH HEATING AND THE APPG TROUGH OF LOW
PRESSURE ALOFT...SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE IN THE
EASTERN CWA TUES AFTN. I DID GO AHEAD AND KEEP THE MENTION OF
THUNDERSTORMS EAST OF A ERICSON TO SPRINGVIEW LINE AS THIS IS WHERE
THE BEST MOISTURE IS LOCATED AT THE TIME OF PEAK HEATING. ACROSS THE
REMAINDER OF NORTHERN NEBRASKA...I DID INCLUDE A MENTION OF SHRAS
AS THESE AREAS AS THEY WILL BE INVOF OF THE H7 FRONT.
TUESDAY NIGHT THROUGH SATURDAY...AN ACTIVE EXTENDED PERIOD PATTERN
IS EXPECTED TO DEVELOP BEYOND TUESDAY. AN UPPER LEVEL TROUGH OF LOW
PRESSURE WILL LIFT ACROSS SOUTH DAKOTA TUESDAY NIGHT. THIS FEATURE
WILL FORCE A STRONG COLD FRONT THROUGH THE FORECAST AREA WEDNESDAY.
RAIN SHOWERS ARE EXPECTED WITH PASSAGE OF THIS FEATURE...AND A MIX
OF RAIN OR SNOW IS POSSIBLE OVER THE NORTHEASTERN PANHANDLE AND
NORTHWESTERN SANDHILLS. PRECIPITATION CHANCES WILL DECREASE WEDS
NIGHT AS THE FIRST UPPER LEVEL TROUGH/LOW TRACKS INTO THE UPPER
MISSISSIPPI VALLEY. IN ITS WAKE...A SECOND UPPER LEVEL TROUGH WILL
DIVE SOUTH ACROSS THE WESTERN DAKOTAS THURSDAY. THIS WILL BRING A
SECOND CHANCE OF RAIN OR SNOW SHOWERS DURING THE DAY AND SNOW DURING
THE NIGHT. QPF/S WILL REMAIN LIGHT WITH THIS SECONDARY SYSTEM...SO
AM NOT EXPECTING ANY DECENT SNOW ACCUMS AT THIS TIME. FRIDAY INTO
SATURDAY WILL BE DRY IN ADVANCE OF AN ARCTIC FRONT SATURDAY NIGHT.
TEMPERATURES FRIDAY AND SATURDAY WILL BE IN THE UPPER 40S TO LOWER
50S...WHILE HIGHS ON WEDNESDAY AND THURSDAY WILL BE IN THE 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1223 PM CDT SAT MAR 26 2016
LIGHT SNOW OVER NORTHWEST NEBRASKA...PRIMARILY NEAR KCDR AND
KIEN...WILL DISSIPATE THROUGH EARLY AFTERNOON. STRATUS COVERING
MUCH OF WESTERN NEBRASKA WILL SLOWLY LIFT FROM WEST TO EAST THIS
AFTERNOON. CENTRAL NEBRASKA...INVOF KONL AND KBBW...WILL LIKELY
STAY IN MVFR CONDITIONS THROUGH THE EVENING. BRISK NORTH WINDS
WILL LIGHTEN AROUND SUNSET AND SLOWLY TRANSITION TO WEST
OVERNIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BUTTLER
SHORT TERM...SNIVELY
LONG TERM...BUTTLER
AVIATION...SNIVELY
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1225 PM CDT SAT MAR 26 2016
.UPDATE...
ISSUED AT 1225 PM CDT SAT MAR 26 2016
ADDED STANTON COUNTY INTO THE WINTER WEATHER ADVISORY. BUMPED UP
SNOW AMOUNTS SLIGHTLY IN THE ADVISORY AREA AND A LITTLE FARTHER TO
THE EAST.
RECENT HRRR AND RUC OUTPUT AS WELL AS 12Z NAM SHOWED COLDER AIR
MOVING EWD ABOUT AS EXPECTED WITH PCPN CONTINUING INTO LATE AFTN
OR EARLY EVENING. SNOW COULD MIX IN AS FAR EAST AS OMAHA.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 344 AM CDT SAT MAR 26 2016
QUICK SHOT OF ACCUMULATING SNOW FOR NORTHEAST NEBRASKA...AND RAIN
FOR THE REST OF EASTERN NEBRASKA AND SOUTHWEST IOWA TODAY...ARE
THE MAIN FORECAST CONCERNS.
SIGNIFICANT CHANGES IN THE FORECAST ARE IN ORDER THIS MORNING...AT
LEAST FOR NORTHEAST NEBRASKA WHERE SEVERAL INCHES OF SNOW IS
POSSIBLE TODAY. STRONG SHORTWAVE WAS NOTED EMERGING THROUGH THE HIGH
PLAINS OF KANSAS AND SOUTHWEST NEBRASKA THIS MORNING...AND WILL
TRACK NORTHEAST THROUGH EASTERN NEBRASKA AND IOWA. 85KT UPPER LEVEL
JET ROUNDING BASE OF SHORTWAVE WILL COUPLE WITH 80KT JET IN THE
NORTHERN PLAINS TO PROVIDE VENTING OF UPPER LEVEL AIR OVER EASTERN
NEBRASKA TODAY...WITH MODELS INDICATING STRONG POSITIVE VERTICAL
VELOCITIES IN OUR AREA. ALREADY SEEING EVIDENCE OF THIS PROCESS
BEGINNING AS RADAR RETURNS WERE INCREASING ACROSS CENTRAL KANSAS
THIS MORNING...JUST AHEAD OF SURFACE LOW DEVELOPING IN SOUTHWEST
KANSAS. THAT LOW WILL TRACK NORTHEAST INTO SOUTHEAST NEBRASKA
LATER THIS MORNING...WITH AREA OF STRONG ISENTROPIC UPGLIDE
PRECEDING LOW AND HELPING TO SATURATE MID AND LOW LAYERS. ALL THIS
POINTS TO INCREASING PRECIPITATION CHANCES ACROSS ALL OF EASTERN
NEBRASKA AND SOUTHWEST IOWA AS WE HEAD THROUGH THE MORNING.
MAXIMUM LIFT AND THUS PRECIP POTENTIAL OCCURS AROUND 18Z-21Z
TIMEFRAME BEFORE SYSTEM SWINGS NORTHEAST LATE IN THE AFTERNOON AND
EARLY EVENING.
MOST OF THE AREA SHOULD SEE RAIN AS TEMPERATURE PROFILES REMAIN ON
LIQUID SIDE OF RAIN/SNOW LINE THROUGH DURATION OF PRECIPITATION.
HOWEVER PROFILES TREND TOWARD SNOW IN NORTHEAST NEBRASKA THROUGH THE
MORNING WITH ONLY SURFACE LAYER REMAINING ABOVE FREEZING BY 18Z.
VARIED MODEL SOLUTIONS WITH REGARD TO CHANGE TO SNOW...FROM WHETHER
IT WILL CHANGE TO WHAT TIME THE CHANGE WILL OCCUR. HOWEVER GIVEN
STRONG VERTICAL VELOCITIES...EXPECT THE CHANGE TO OCCUR BETWEEN 15Z
AND 18Z GENERALLY NORTHWEST OF A COLUMBUS TO WAYNE LINE...WITH A
GRADUAL CHANGE TO THE SOUTHEAST OF THAT LINE IN THE EARLY AFTERNOON.
SURFACE TEMPERATURES WILL LIKELY REMAIN NEAR OR ABOVE FREEZING...AND
SNOW WILL FALL DURING THE DAYLIGHT HOURS...BOTH NEGATIVES IN
REGARDS TO SNOW ACCUMULATION. AGAIN...STRONG LIFT WILL OVERCOME
THESE NEGATIVES...BUT TOTAL ACCUMULATION WILL BE TRICKY. GARCIA
CALCULATIONS FOR A 3 TO 6 HOUR SNOWFALL POINT TO MAX AMOUNTS NEAR
4 INCHES OVER A SMALL AREA OF NORTHEAST NEBRASKA. STRAIGHT MODEL
OUTPUT AND COBB METHOD WOULD SUGGEST A LITTLE MORE. THINK A
WINTER WEATHER ADVISORY IS APPROPRIATE FOR THIS QUICK SHOT OF
SNOW...ESPECIALLY GIVEN THE RECENT SNOWS OVER THE SAME AREA.
PRECIPITATION WILL BE ENDING FROM SOUTHWEST TO NORTHEAST THIS
EVENING...WITH DECREASING CLOUDS EXPECTED LATE TONIGHT AND SUNDAY.
LOWS IN THE 20S ARE EXPECTED TO START EASTER SUNDAY...WITH LOTS OF
AFTERNOON SUNSHINE AND LIGHT WEST WINDS PUSHING HIGHS BACK INTO THE
50S FOR THE AFTERNOON. MID LEVEL RIDGING IS FORECAST TO START OFF
NEXT WEEK...WITH PLENTY OF SUN AND A BACKDROP OF WARMING LOW LEVEL
ATMOSPHERE SUGGESTING HIGHS IN THE 60S ARE ON TARGET FOR MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 344 AM CDT SAT MAR 26 2016
MILD TEMPERATURES SHOULD CONTINUE INTO MID WEEK BEFORE STRONG COLD
FRONT BRINGS A SHOT AT SHOWERS OR STORMS...WITH COOLER TEMPS TO END
THE WEEK.
UPPER RIDGING MONDAY WILL BE REPLACED BY SOUTHWEST FLOW TUESDAY
INTO WEDNESDAY AS UPPER LOW/TROUGH MOVES TO THE FOUR CORNERS
REGION. MODELS INDICATE TROUGH WILL MOVE EAST IN PHASES...WITH GFS
MORE PRONOUNCED IN TRACKING A SIGNIFICANT CHUNK OF ENERGY INTO THE
PLAINS WEDNESDAY. ECMWF HANGS MORE ENERGY IN THE ROCKIES A LITTLE
LONGER...BUT BOTH COME AROUND TO SIMILAR PATTERNS BY THURSDAY
NIGHT WHEN TROUGH AXIS MOVES INTO OUR FORECAST AREA.
NOT MUCH DIFFERENCE AS FAR AS SENSIBLE WEATHER GOES THOUGH. WARM
ADVECTION MAY TOUCH OFF SHOWERS OR ISOLATED THUNDER TUESDAY INTO
TUESDAY NIGHT BEFORE COLD FRONT SWINGS THROUGH THE REGION ON
WEDNESDAY. CURRENT TIMING OF THAT FRONT PUTS BEST SEVERE RISK EAST
OF OUR AREA AS WINDS SHIFT TO THE NORTHWEST EARLY IN THE DAY.
STILL A CHANCE FOR THUNDERSTORMS ALONG THE FRONT. COOL AIR RUSHING
IN BEHIND MAY SWITCH LINGERING SHOWERS TO SNOW IN NORTHEAST
NEBRASKA BEFORE PRECIP ENDS THURSDAY MORNING.
HIGHS IN THE 60S OR 70S TUESDAY AND WEDNESDAY LOOK TO ONLY FALL TO
THE 50S THURSDAY AND FRIDAY BEHIND THIS SYSTEM.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1225 PM CDT SAT MAR 26 2016
COLD FRONT WILL CONTINUE TO MOVE EWD. EXPECT MAINLY IFR TO LIFR
CONDITIONS UNTIL PCPN ENDS LATE AFTN OR EARLY EVENING. THEN LOOK
FOR LOW CLOUDS TO SCT OUT LATER THIS EVENING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NEZ011-
012-016>018-030>032-042.
IA...NONE.
&&
$$
UPDATE...MILLER
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS RALEIGH NC
140 PM EDT SAT MAR 26 2016
.SYNOPSIS... COOL HIGH PRESSURE WILL BUILD SOUTH INTO THE
AREA TODAY AND TONIGHT AS A WAVY FRONT STALLS ALONG THE SOUTHEAST
COAST. THE FRONT WILL LIFT NORTH ACROSS THE AREA AS A WARM FRONT LATE
SUNDAY AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES THROUGH
THE AREA ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1035 AM SATURDAY...
IT APPEARS THE COLD FRONT HAS FINALLY SETTLED INTO SC...AIDED SLOWLY
BY VERY SHALLOW (ONLY ~1000FT) NORTHEAST FLOW AND COLD ADVECTION.
ISENTROPIC LIFT ATOP THE COOL DOME IS ALSO WEAK WITH ONLY 10-20KT AT
290-295K PER RAP ANALYSIS. STRATUS HAS BEEN PATCH AND CONFINED TO
THE SOUTHERN CWA BUT IS STARTING TO FILL IN ACROSS THE PIEDMONT. THE
LACK OF STRATUS AND ONLY THIN CIRRUS TO FILTER THE SUN HAS ALLOWED
TEMPS TO WARM UP IN THE WESTERN AND CENTRAL PIEDMONT...SO HIGHS WILL
NEED TO BE RAISED A FEW DEGREES. SKIES WILL EVENTUALLY BECOME
OVERCAST BY THIS AFTERNOON...SO EXACTLY HOW MUCH ADDITIONAL WARMING
IS POSSIBLE IS TOUGH TO SAY. A BLEND OF GUIDANCE THAT APPEARS TO
AVE CAUGHT ON TO THE TREND SUGGESTS MANY LOCATIONS WILL HIT
60S...WITH MID/UPPER 40S IN THE CENTRAL AND NORTHERN PIEDMONT.
ISENTROPIC LIFT WILL INCREASE THIS AFTERNOON AND
EVENING...ESPECIALLY OVER THE COASTAL PLAIN...AS A WAVE OF LOW
PRESSURE DEVELOPS ALONG THE FRONT IN RESPONSE TO A LOW-AMPLITUDE
SHORTWAVE LIFTING OUT OF THE CENTRAL PLAINS TROUGH. THE CURRENT POP
FORECAST LOOKS PRETTY GOOD...SO WILL JUST MAKE MINOR CHANGES TO SLOW
THE ARRIVAL OF MORE WIDESPREAD RAIN...WHICH SHOULD BE MORE TOWARD
00Z PER HIRES GUIDANCE. CHANGES RESULT IN CHANCE POPS NORTHWEST AND
LIKELY POPS SOUTHEAST...WITH QPF RANGING FROM A FEW HUNDREDTHS
NORTHWEST TO AROUND A TENTH OF AN INCH SOUTHEAST.
THE CHANCE OF PATCHY LIGHT RAIN OR DRIZZLE WILL PERSIST OVERNIGHT.
LOWS OVERNIGHT IN THE UPPER 40S NW TO MID 50S SE.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 345 AM SATURDAY...
DREARY CLOUDY CONDITIONS ASSOCIATED WITH HYBRID DAMMING WILL
CONTINUE ON SUNDAY. THE WEAKENING FRONT TO OUR SOUTH IS EXPECTED
TO LIFT NORTH AS A WARM FRONT LATE IN THE AFTERNOON AND EVENING...
IN ADVANCE OF SHORTWAVE TROUGH AND ATTENDANT SFC FRONT ADVANCING
EASTWARD INTO CENTRAL AND SOUTHERN APPALACHIANS. RESULTANT WAA COUPLED
WITH ANY SHORTWAVE PERTURBATIONS EJECTING OUT AHEAD OF THE AFOREMENTIONED
UPSTREAM SHORTWAVE TROUGH WILL SUPPORT AN INCREASING CHANCE OF SHOWERS
SUNDAY AND SUNDAY NIGHT. THERE CONTINUES TO BE SIGNALS IN THE MODELS
OF A CLASSIC "CAROLINA SPLIT"...WHERE CENTRAL NC EXPERIENCES A SIGNIFICANT
REDUCTION/VOID IN PRECIP AS ENERGY/FORCING SPLITS TO OUR NW WITH THE PARENT S/W
TROUGH STAYING NORTH OF THE AREA AND TO OUR SOUTHEAST WITH ANOTHER POSSIBLE
COASTAL LOW DEVELOPMENT AND ASSOCIATED CONVECTION.
SHOULD BE A LITTLE WARMER GIVEN WEAKENING CAD. HIGHS IN THE LOWER 60S NORTH
TO NEAR 70S SOUTH WITH MINIMAL COOLING OVERNIGHT. LOWS IN THE MID 50S TO LOWER
60S.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 250 AM SATURDAY...
MON AND MON NIGHT: THERE COULD BE SOME LINGERING SHOWER ACTIVITY MON
MORN AS THE UPPER LEVEL TROUGH AXIS PASSES OVER NC...OTHERWISE
EXPECT THE SURFACE FRONT TO PUSH THROUGH DURING THE DAY MON...WITH
DRYING AND CAA BEHIND IT. BOTH THE GFS AND ECMWF MOVE THE FRONT
THROUGH AND THE RAIN OUT OF THE AREA BY MON NIGHT. GIVEN THE CURRENT
FROPA TIMING...THERE WILL BE QUITE A GRADIENT IN HIGHS MON... AROUND
70 DEGREES NW TO MID 70S SE. MON NIGHT LOWS IN THE LOW TO MID 40S.
TUE THROUGH WED: A RETURN OF DRY AND SLIGHTLY COOLER WEATHER FOR MID-
WEEK WITH HIGH PRESSURE BUILDING IN AT THE SURFACE AND RIDGING
ALOFT. HIGHS IN THE MID TO UPPER 60S TUE AND WED. LOWS MODERATING
FROM UPPER LOW 40S TUE NIGHT TO MID TO AROUND 50 DEGREES WED NIGHT.
THE NEXT ROUND OF RAIN COULD MOVE INTO THE WEST AS EARLY AS WED
NIGHT AS A FRONTAL SYSTEM APPROACHES FROM THE WEST...BUT WILL MAY
HOLD OFF UNTIL THU. THERE IS STILL A LARGE DIFFERENCE IN TIMING
BETWEEN THE MODELS...GFS FASTER THAN ECMWF.
THU THROUGH SAT: AS A LOW PRESSURE SYSTEM MOVES THROUGH THE MIDWEST
FROM CO TO THE GREAT LAKES...THE ASSOCIATED COLD FRONT WILL PUSH
EASTWARD TOWARD THE CAROLINAS. THE SURFACE HIGH WILL BE PUSHED OUT
OF THE AREA AS THE WARM FRONT LIFTS NORTHWARD THROUGH CENTRAL NC WED
NIGHT. MEANWHILE...A SURFACE LOW WILL DEVELOP OVER THE TX GULF COAST
AND MOVE NE ALONG THE FRONT. TIMING OF RAINFALL ONSET...DURATION...
AND FROPA TIMING ARE ALL STILL FAIRLY UNCERTAIN. GENERALLY THOUGH...
EXPECT MODERATING TEMPS AND INCREASING RAIN CHANCES THU THROUGH FRI.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY....
AS OF 140 PM SATURDAY...
MOSTLY MVFR CEILINGS ARE OBSERVED ACROSS CENTRAL NC THIS AFTERNOON
WITH HIGH PRESSURE NOSING IN FROM THE NORTH AND A FRONT STALLED JUST
SOUTH OF THE NC BORDER. A FEW CLUSTERS OF SHOWERS AND ISOLATED
STORMS WILL MAKE A RUN AT NC FROM THE SOUTH THIS AFTERNOON AND
EVENING...MOSTLY WEAKENING AS THEY MOVE NORTH OF THE FRONT...THOUGH
AN ISOLATED STORMS IS POSSIBLE AROUND KFAY THROUGH 00Z. LIGHT RAIN
IS EXPECTED TO FILL IN ACROSS THE COASTAL PLAIN AND PORTIONS OF THE
PIEDMONT THIS EVENING AS A WAVE OF LOW PRESSURE TRACKS ALONG THE
FRONT AND OFFSHORE. CONFIDENCE IN THE RESULTING CEILING HEIGHTS AND
RAINFALL INTENSITY IS LOW GIVEN POOR MODEL PERFORMANCE IN THE PAST
24 HOURS. IT SEEMS AS THOUGH IFR CEILINGS WILL DEVELOP BY 06Z AT
MOST LOCATIONS...WITH SOME LIFR CEILINGS POSSIBLE LATER TONIGHT AND
EARLY SUNDAY. IF LOWER CEILINGS DO DEVELOP...THEY WILL LINGER WELL
INTO THE DAY ON SUNDAY...WITH SLOW IMPROVEMENT POSSIBLE MAINLY
AROUND KFAY AND KRWI BY SUNDAY AFTERNOON.
OUTLOOK: SUB-VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH SUNDAY
NIGHT AS MOISTURE LINGERS BETWEEN THE LOW PRESSURE DEPARTING THE NC
COAST AND A COLD FRONT APPROACHING FROM THE WEST. THE COLD FRONT
WILL SWEEP ACROSS THE AREA ON MONDAY..WITH GUSTY NORTHWEST WINDS AND
VFR CONDITIONS BEHIND THE FRONT. VFR CONDITION SHOULD THEN CONTINUE
THROUGH MIDWEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...22/CBL
SHORT TERM...CBL
LONG TERM...KCP
AVIATION...22
AREA FORECAST DISCUSSION
NWS PORTLAND OR
309 PM PDT SAT MAR 26 2016
.SYNOPSIS...A COLD FRONT WILL BRING RAIN TONIGHT WITH SHOWERY
COOL WEATHER FOR SUN INTO MON. SNOW LEVEL WILL DROP OVERNIGHT AND
BRING SEVERAL INCHES OF SNOW TO THE CASCADE PASSES THROUGH MON.
THEN DRY AND MILD WEATHER STARTS TUE...AND LASTS THROUGH MUCH OF
NEXT WEEK AS REGION WILL BE UNDER HIGH PRES.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY) THE WARM FRONT OFFSHORE
EXTENDS TO JUST SOUTH OF THE CWA THIS AFTERNOON. SPOTTY LIGHT RAIN
CONTINUES ALONG THE COAST AND CASCADES ZONES. FURTHER NORTH THERE ARE
DECENT BREAKS IN THE CLOUD COVER. MEANWHILE AN OCCLUDING COLD FRONT
ABOUT 400 MILES OFFSHORE IS FORECAST TO REACH THE COAST AROUND
10 PM TONIGHT THEN ACROSS THE INTERIOR ZONES INTO THE CASCADES
AROUND MIDNIGHT. EXPECT RAIN TO FILL IN LATER THIS AFTERNOON AND
EVENING AS THE FRONT MOVES THROUGH...AS THE 20Z HRRR AND 12Z WRFGFS
SUGGEST.
RAIN WILL TAPER TO SHOWERS BEHIND THE FRONT...WHILE SNOW LEVELS LOWER
TO AROUND 3000-3500 FT BY SUNDAY MORNING. WITH PRECIPITATION BECOMING
MORE SHOWERY OR HIT AND MISS IN NATURE BY THAT TIME... SIGNIFICANT
ACCUMULATIONS ARE NOT EXPECTED. GENERALLY 2 TO 6 INCHES OF NEW SNOW
FOR SUN OVER THE CASCADES...AND BIT MORE SUN NIGHT.
WITH THE COLD POOL ALOFT MOVING OVER THE REGION ON SUN...SEEMS THAT
WILL HAVE GOOD CONDITIONS FOR PLENTY OF SHOWERS AND PERHAPS A
THUNDERSTORM OR TWO. MODEL SOUNDINGS STILL SUPPORT MINOR CONVECTIVE
POTENTIAL ENERGY...SO WILL KEEP THREAT OF THUNDER IN FORECAST FOR SUN
AFTERNOON/EVENING. WITH LOWER FREEZING LEVELS...HEAVIER SHOWERS WILL
HAVE THE POTENTIAL TO PRODUCE SMALL HAIL.
THE UPPER LOW AND ASSOCIATED UNSTABLE AIR MASS WILL GRADUALLY SHIFT
S-SE TOWARD THE GREAT BASIN EARLY NEXT WEEK...WITH NORTHERLY FLOW
USHERING IN DRIER AIR. MODELS SUGGEST A FEW SHOWERS LINGERING INTO
MONDAY...ESPECIALLY IN THE HIGHER TERRAIN. MONDAY NIGHT MAY BE THE
COOLEST NIGHT IN A WHILE...WITH SOME FROST POSSIBLE IN THE OUTLYING
VALLEYS AS HIGH PRESSURE AND CLEARING SKIES PROVIDE A GOOD
ENVIRONMENT FOR RADIATIONAL COOLING. THE CLEARING/DRYING TREND
CONTINUES INTO TUESDAY FOR PLENTY OF SUNSHINE AND NEAR NORMAL
AFTERNOON TEMPS AFTER A CHILLY START. MH/SMW/CCDR
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY. NO CHANGES TO THE EXTENDED
TODAY WITH MODELS REMAINING IN GOOD AGREEMENT. STRONG UPPER RIDGE
BUILDS OVER THE PACIFIC NORTHWEST AND WILL REMAIN IN PLACE THROUGH
MUCH OF NEXT WEEK. THIS MEANS A PERIOD OF NICE WEATHER...WARMER
TEMPERATURES WITH AFTERNOON HIGHS WELL INTO THE 60S AND GENERALLY
CLEAR SKIES FOR THE SECOND HALF OF THE WEEK WITH MODEST OFFSHORE
FLOW DEVELOPING BY MIDWEEK. AFTER THE ACTIVE WEATHER TO OPEN THE
MONTH AND WITH MILD AND TRANQUIL WEATHER ON TAP FOR THE END...IT
LOOKS LIKE THE OLD ADAGE OF MARCH ENTERING LIKE A LION AND EXITING
LIKE A LAMB WILL HOLD THIS YEAR. CULLEN
&&
.AVIATION...A SERIES OF WEAK FRONTS WILL IMPACT THE REGION TODAY
AND TONIGHT. CONDITIONS ARE GENERALLY VFR ACROSS THE FORECAST AREA
WITH LOCAL MVFR ALONG THE CENTRAL COAST AND IN THE SOUTH VALLEY.
EXPECT MVFR CIGS TO SPREAD NORTH LATER THIS AFTERNOON/EVENING WITH
THE COLD FRONT MOVING ONSHORE TONIGHT. THIS WILL BRING INCREASING
RAIN CHANCES TO THE REGION TONIGHT. CONDITIONS BECOME MORE SHOWERY
LATE TONIGHT WITH CIGS TRENDING TOWARDS VFR ON SUNDAY.
KPDX AND APPROACHES...PRIMARILY VFR THROUGH THIS EVENING WITH CIGS
AROUND 4000 FT. WILL SEE A FEW HOURS OF MVFR CIGS TONIGHT AS THE
COLD FRONT MOVES ACROSS THE TERMINAL. RAIN CHANCES WILL CONTINUE
TO INCREASE TONIGHT. CONDITIONS BECOME SHOWERY LATE TONIGHT WITH
CIGS TRENDING TOWARDS VFR ON SUNDAY. /64
&&
.MARINE...A SERIES OF WEAK FRONTAL SYSTEMS WILL IMPACT THE WATERS
TODAY AND TONIGHT. THERE WERE A FEW HOURS OF MARGINAL SCA WIND
GUSTS THIS MORNING AS THE WARM FRONT MOVED ACROSS THE WATERS.
HOWEVER...THE BEST CHANCES OF SCA WINDS CONTINUE TO HOLD OFF
UNTIL AFTER THE COLD FRONT MOVES ACROSS THE WATERS THIS EVENING.
STRONGEST WINDS LOOK TO REMAIN OVER THE NORTHERN WATERS SO WILL
CONTINUE THE SCA FOR WINDS THERE. THE CENTRAL OREGON WATERS COULD
SEE SOME MARGINAL SCA WINDS...BUT NOT ENOUGH TO WARRANT AN
ADVISORY.
WILL SEE NORTHERLY FLOW STRENGTHEN LATE SUNDAY AS HIGH PRESSURE
BUILDS ACROSS THE NORTHEAST PACIFIC. THIS WILL BRING A PERIOD OF
SUMMER-LIKE CONDITIONS WITH GUSTY NORTHERLY WINDS POSSIBLE
THROUGH MUCH OF NEXT WEEK. AS OF NOW IT LOOKS LIKE WE COULD SEE A
ROUND OF NORTHERLY SCA WINDS DEVELOP LATE SUNDAY AND CONTINUE INTO
MONDAY. WILL HOLD OFF ON ISSUING A SCA UNTIL AFTER THE CURRENT SCA
EXPIRES.
SEAS ARE CURRENTLY AROUND 5 FT. HOWEVER...PERSISTENT AND LONG
NORTHWEST WIND FETCH WILL BRING COMBINED HYBRID SWELL/FRESH SWELL
SEAS BACK ABOVE 10 FT SUNDAY EVENING. SEAS WILL BE RATHER CHOPPY
AS PERIODS WILL HOVER AROUND 10-12 SECONDS. SEAS SUBSIDE BELOW 10
FT AGAIN AS THE FLOW TURNS MORE NORTHERLY BY MIDWEEK. /64/JBONK
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 PM THIS EVENING TO 9 AM
PDT SUNDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
CASCADE HEAD OR OUT 60 NM.
&&
$$
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 MEDFORD OR
907 AM PDT SAT MAR 26 2016
.DISCUSSION...INTERMITTENT LIGHT RAIN IS MOVING INTO THE AREA
THIS MORNING IN ASSOCIATION WITH A WARM FRONT. RAINFALL AMOUNTS
ARE EXPECTED TO BE LIGHT, BUT ENOUGH TO WET SURFACES. EXPECT THIS
TO CONTINUE INTO THIS AFTERNOON, ALTHOUGH THERE COULD BE MORE
BREAKS IN BETWEEN. THIS IS IN LINE WITH THE LATEST SHORT RANGE
MODEL LIKE THE HRRR AND RAP. THUS HAVE ADJUSTED QPF AMOUNTS DOWN
FOR TODAY, BUT KEPT POPS THE SAME. IN FACT THE LARGEST AREA OF
PRECIPITATION IS IN NORTHERN OREGON AND IS MOVING EAST. THERE IS
ALSO A LINE OF LIGHT RAIN THAT IS MOVING THROUGH THE ROGUE VALLEY,
BUT THIS SHOULD LAST LESS THAN AN HOUR BEFORE MOVING EAST.
A COLD FRONT WILL MOVE INTO THE AREA OVERNIGHT TONIGHT AND MOVE
SOUTH OF THE AREA SUNDAY MORNING. EXPECT SCATTERED SHOWERS MAINLY
WEST OF THE CASCADES WITH COOLER TEMPERATURES THE REST OF SUNDAY.
A PRELIMINARY LOOK AT THE MODELS SUGGEST MOST OF THE SHOWERS WILL
BE WEST OF THE CASCADES WITH MOST CENTERED ALONG THE WEST FACING
SLOPES OF THE CASCADES. -PETRUCELLI
&&
.AVIATION...FOR THE 26/12Z TAF CYCLE...VFR WILL PREVAIL AT MOST
INLAND TERMINALS THROUGH THE MORNING. A WARM FRONT WILL BRING SOME
LIGHT RAIN AND LOWERING CEILINGS TO THE COAST AROUND DAWN THIS
MORNING AND THEN INTO THE UMPQUA BASIN LATE MORNING. CONDITIONS ARE
LIKELY TO REMAIN VFR ELSEWHERE SATURDAY...THOUGH TERRAIN MAY BECOME
PARTIALLY OBSCURED AS CIGS LOWER INLAND LATER THIS MORNING AND INTO
THE AFTERNOON WITH AREAS OF LIGHT RAIN. SVEN/SK
&&
.MARINE...UPDATED 2 AM PDT SAT 26 MAR 2016...WEST SWELL HAS SUBSIDED
BELOW 10 FEET ACROSS THE WATERS AND SHOULD REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS THROUGH SUNDAY. A FEW WEAK FRONTS WILL MOVE THROUGH
TODAY AND SUNDAY. THUNDERSTORMS ARE POSSIBLE OVER THE WATERS SUNDAY
EVENING. A PERIOD OF STRONGER NORTH WINDS AND STEEPER SEAS IS LIKELY
MONDAY INTO MONDAY NIGHT AS HIGH PRESSURE BUILDS BACK INTO THE AREA.
SMALL CRAFT ADVISORY CONDITIONS FOR WINDS AND SEAS ARE POSSIBLE
MONDAY. NORTH TO NORTHEAST WINDS WILL CONTINUE INTO THE MIDDLE OF
WEEK. SK
&&
.PREV DISCUSSION... /ISSUED 650 AM PDT SAT MAR 26 2016/
UPDATED AVIATION DISCUSSION.
SHORT TERM...A WARM FRONT WILL MOVE INLAND TODAY AND BRING WET
WEATHER. A COLD FRONT WILL THEN MOVE INLAND DURING THE EVENING
AND NIGHT, BRINGING SHOWERS TO THE AREA AND LOWERING SNOW
LEVELS. ON SUNDAY, AN UPPER LOW WILL DROP DOWN INTO THE PACNW.
THIS UPPER LOW WILL GRADUALLY SHIFT SOUTH-SOUTHEASTWARD SUNDAY
NIGHT AND MONDAY. WITH THE LOW, EXPECT A SHOWERY AND COLDER
PATTERN TO DEVELOP ACROSS THE AREA SUNDAY AND MONDAY.
MODELS HAVE TRENDED WETTER WITH THE WARM FRONT MOVING INTO THE
AREA TODAY. THIS FRONT IS FORECAST TO BRING LIGHT RAIN FOR MOST
AREAS WEST OF THE CASCADES IN SOUTHWEST OREGON THIS
MORNING...THEN PRECIPITATION WILL SPREAD INTO THE CASCADES AND
INTO EAST SIDE AREAS. ACROSS NORTHERN CALIFORNIA, EXPECT LESS
WIDESPREAD PRECIPITATION WITH BEST CHANCES FOR PRECIPITATION IN
SISKIYOU COUNTY AND SLIGHT CHANCE INTO MODOC COUNTY. SNOW LEVELS
WILL RISE AS THIS FRONT MOVES INTO THE AREA...INCREASING TO 6000
TO 7000 FEET ACROSS THE AREA THIS AFTERNOON INTO EARLY THIS
EVENING.
THIS EVENING AND TONIGHT, A COLD FRONT IS FORECAST TO MOVE INLAND.
THIS WILL BRING LIGHT SHOWERS, WITH BEST CHANCES FROM THE CASCADES
WEST. ALSO SNOW LEVELS WILL GRADUALLY LOWER FROM 6000 TO 7000 FEET
DOWN TO AROUND 5000 TO 6000 FEET LATE THIS EVENING INTO TONIGHT
FROM THE SOUTHERN OREGON CASCADES WESTWARD.
ON SUNDAY MORNING, SHOWERS ARE EXPECTED TO BE MAINLY LIGHT AND
LESS WIDESPREAD WITH BEST CHANCES FOR LIGHT SHOWERS ALONG THE
COAST AND INLAND OVER DOUGLAS COUNTY. HOWEVER, SHOWER ACTIVITY
IS FORECAST TO INCREASE SUNDAY AFTERNOON AND EVENING, MAINLY FROM
THE CASCADES WEST AS THE UPPER LOW SHIFTS INTO OREGON AND
WASHINGTON. SNOW LEVELS ARE EXPECTED TO BE AROUND 4000 TO 4500 FEET
SUNDAY FROM THE SOUTHERN CASCADES WEST. EAST OF THE CASCADES AND
OVER NORTHERN CALIFORNIA EXPECT SNOW LEVELS TO LOWER MORE GRADUALLY
DOWN TO 4500 TO 6000 FEET ON SUNDAY.
SUNDAY NIGHT, THE UPPER LOW WILL SHIFT SOUTHEAST AND BECOME
CENTERED OVER EASTERN OREGON THEN GRADUALLY SHIFT FURTHER
EAST DURING THE DAY MONDAY. THIS LOW WILL BRING A COLD AIR MASS
ALOFT WITH 500 MB TEMPERATURES OF -34C MOVING INTO EASTERN
PORTIONS OF THE AREA. SNOW LEVELS WILL CONTINUE TO LOWER SUNDAY
NIGHT TO AROUND 2500 FEET ELEVATION AND REMAIN LOW ON MONDAY.
LOCALLY SNOW LEVELS OF 2000 FEET ARE POSSIBLE MONDAY MORNING.
MODELS HAVE TRENDED FURTHER INLAND WITH THE TRACK OF THE LOW AND
AS A RESULT PRECIPITATION IS EXPECTED TO BE MAINLY LIGHT. ANY
SNOW THAT FALLS IS EXPECTED TO ONLY BRING LIGHT ACCUMULATIONS.
CURRENT FORECASTS INDICATION AROUND 1 TO 3 INCHES ON SNOW
ACCUMULATING IN THE CASCADES AND SISKIYOUS SUNDAY NIGHT AND MONDAY
MORNING, WITH GENERALLY LESS THAN AN INCH BELOW 3000 FEET
ELEVATION. AS THE LOW SHIFTS SOUTHEAST, EXPECT WRAP AROUND
MOISTURE TO BRING SOME ENHANCED SHOWERS TO LAKE COUNTY AND INTO
EASTERN MODOC COUNTY, ESPECIALLY TO THE WARNER AND HART MOUNTAINS.
THESE AREAS MAY EXPECT AROUND 1 TO 3 INCHES OF SNOW ACCUMULATION SUNDAY
NIGHT INTO MONDAY MORNING. LOW TEMPERATURES SUNDAY NIGHT AND
MONDAY MORNING WILL LOWER INTO THE MID 30S FOR MANY VALLEYS WEST
OF THE CASCADES IN SOUTHWEST OREGON AND INTO THE LOWER 30S FOR
VALLEYS IN SISKIYOU COUNTY. EAST SIDE AREAS WILL SEE LOW
TEMPERATURES IN THE 20S. HIGH TEMPERATURES DURING THE DAY MONDAY
WILL BE COOLER THAN NORMAL BY 7 TO 10 DEGREES. HIGH TEMPERATURES
ARE EXPECTED TO RISE INTO THE LOWER TO MID 50S FOR WESTERN VALLEYS
AND INTO THE LOW 40S FOR EAST SIDE VALLEYS.
MONDAY AFTERNOON AND EVENING, THE LOW WILL GRADUALLY SHIFT EAST
AND EXPECT SHOWER ACTIVITY TO DECREASE OVER THE AREA MONDAY
EVENING THEN TAPER OFF FOR WESTERN AREAS BY EARLY TUESDAY.
LINGERING WRAP AROUND SHOWERS ARE POSSIBLE THROUGH TUESDAY FROM
THE CASCADES EASTWARD. MORE SEASONABLE TEMPERATURES WILL DEVELOP
DURING THE DAY TUESDAY FOR WESTERN VALLEYS WITH HIGHS IN THE MID
50S TO LOW 60S. AREAS EAST OF THE CASCADES WILL REMAIN BELOW
NORMAL WITH HIGHS EXPECTED IN THE MID TO UPPER 40S ON TUESDAY.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$