Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/21/15
AREA FORECAST DISCUSSION
NWS ALBANY NY
1243 AM EST THU NOV 19 2015
.SYNOPSIS...
A WARM FRONT WILL WORK ACROSS OUR REGION TONIGHT...KEEPING
TEMPERATURES MILD UNDER A CANOPY OF INCREASING CLOUDS. SPOTTY
DRIZZLE WILL BREAK OUT EARLY THURSDAY...FOLLOWED BY HEAVIER
SHOWERS LATER IN THE DAY WHICH WILL BE AHEAD OF A COLD FRONT THAT
WILL CROSS OUR REGION THURSDAY NIGHT. COOLER DRIER AIR WILL FOLLOW
FOR FRIDAY... FOLLOWED BY EVEN COLDER AIR AND SOME SHOWERS OF RAIN
OR SNOW FOR LATER IN THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
CLOUDS AND SLOWLY INCREASING WINDS THROUGH THE EARLY MORNING
HOURS. SOME INDICATIONS OF SOME SPOTTY LIGHT RAIN AND DRIZZLE IN
SOME AREAS...SHOULD VERY GRADUALLY INCREASE IN COVERAGE TOWARD
DAYBREAK...BUT STILL JUST CHANCES. THE MORE WIDESPREAD RAIN IS
SEEN IN WESTERN NY AND WILL AFFECT OUR REGION THROUGH THE DAY.
TEMPERATURES HAVE REACHED THEIR LOWS IN THE UPPER 40S TO LOWER
50S...AND SLOWLY RISE THROUGH SUNRISE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
BY THURSDAY...OUR WHOLE AREA WILL BE IN A MOIST MILD AIR MASS
WITH A COLD FRONT RAPIDLY APPROACHING FROM THE WEST.
THIS IS THE SAME SYSTEM THAT PRODUCED QUITE AN ARRAY OF FOUL WEATHER
OUT WEST...INCLUDING SEVERE WEATHER AND EVEN BLIZZARD CONDITIONS.
NEITHER IS EXPECTED FOR US (INSTABILITY NOT THERE FOR ANY REAL
CONVECTION). A RUMBLE OF THUNDER IS CERTAINLY POSSIBLE BUT WITH
SHOWALTER VALUES >0 AND CAPE VALUES NEAR 0 J/KG WILL KEEP
ANY MENTION OF THUNDERSTORMS OUT OF THE GRIDS FOR NOW.
THAT SAID...WITH PWATS SOARING PAST AN INCH....TWO STANDARDS ABOVE
NORMAL. THE COMBINATION OF THIS MOISTURE...THE FRONT...SHORTWAVE
ENERGY AND OUR AREA COMING UNDER THE DIVERGENT AREA OF THE RR 100KT
NIGHT BY EVENING...ALL POINT TO ROUND OF SHOWERS...SOME CONTAINING
MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL.
WHAT IS A LITTLE DIFFERENT FROM PREVIOUS RUNS...THERE IS LESS OF TENDENCY FOR
A SECONDARY WAVE TO DEVELOP ALONG THE TRIPLE POINT...AS THERE WAS
IN SOME EARLIER RUNS. IT LOOKS LIKE A PROGRESSIVE SYSTEM...PRETTY MUCH
WHAT WE HAVE SEEN THIS AUTUMN.
A GUSTY SOUTH WIND WILL ENSUE ON THURSDAY...10-15 MPH...WITH GUSTS
25-35 MPH ACROSS PORTIONS OF THE HIGHER TERRAIN...AND EVEN
SOME SECTIONS OF THE CAPITAL REGION AND MOHAWK VALLEY. DURING
HEAVY SHOWERS...IT IS REMOTELY POSSIBLE THAT SOME GUSTS COULD EVEN
REACH A LITTLE HIGHER THAN THAN THAT...BUT JUST BRIEFLY.
THEREFORE...NO WIND HEADLINES WERE ASSIGNED WITH THIS PACKAGE.
THE ACTUAL COLD FRONT LOOKS TO MOVE ON THROUGH THURSDAY EVENING...
FOLLOWED BY HIGH PRESSURE BEGINNING TO BUILD IN BY EARLY FRIDAY.
IN FACT...THE SKY MIGHT ACTUALLY CLEAR BY DAYBREAK FRIDAY OR AT
LEAST PARTIALLY CLEAR.
BASED ON UPSTREAM TEMPERATURES WELL INTO THE 60S...WE WILL GO SLIGHTLY
HIGHER THAN ALL MACHINE GUIDANCE ON THURSDAY. LOOK FOR HIGHS LOWER TO MID
60S IN THE VALLEYS...MID OR UPPER 50S EVEN ACROSS THE HIGHER TERRAIN.
TURNING COOLER...BUT STILL ABOVE NORMAL THURSDAY NIGHT WITH LOWS
RANGING FROM THE UPPER 30S TO MID 40S.
FRIDAY SHOULD FEATURE AT LEAST PARTIAL SUNSHINE AS THE FLOW LOOKS TOO ANTI-
CYCLONIC FOR MUCH LAKE INDUCED CLOUDS (OUTSIDE OF THE ADIRONDACKS WHERE
UPSLOPE CLOUDS AND A FEW SHOWERS OF RAIN OR RAIN AND WET SNOW MIXED ARE
POSSIBLE).
HIGH TEMPERATURES WILL BE NOTICEABLY COOLER THAN THURSDAY...HIGHS NEAR 50
IN THE VALLEYS...LOWER TO MID 40S HIGHER TERRAIN...CLOSER TO 40
ACROSS THE ADIRONDACKS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE EXTENDED OPENS WITH A POTENT UPPER LEVEL TROUGH APPROACHING FROM
THE GREAT LAKES REGION AND THE MIDWEST. THE UPPER LEVEL TROUGH
TURNS NEGATIVELY TILTED ACCORDING TO LATEST GFS/ECMWF...AS THE SFC
CYCLONE LIFTS NORTHEAST ACROSS THE ERN GREAT LAKES REGION INTO SE
ONTARIO BY 12Z SUN. THERE IS ENOUGH MOISTURE WITH THE OCCLUDED
FRONT TO THE SYSTEM FOR A PERIOD OF RAIN SHOWERS TRANSITIONING TO
SNOW SHOWERS. THERE IS DECENT LIFT AND CONVERGENCE WITH THE
BOUNDARY. SOME LIGHT SNOW ACCUMULATIONS ARE POSSIBLE WITH A COATING
TO LESS THAN A HALF AN INCH IN THE VALLEY AREAS...AND AN INCH OR TWO
OVER THE HIGHER TERRAIN. THE LIGHT SNOW IS SUPPORTED FROM SOME OF
THE ENSEMBLES. THE LATEST GEFS PLUME DIAGRAM YIELDS ABOUT A TENTH OF
AN INCH OF SNOWFALL FOR ALBANY WITH PERHAPS A HALF DOZEN MEMBERS OR
SO. LOWS SAT NIGHT WILL RANGE FROM THE MID AND U20S OVER THE MTNS TO
U20S TO L30S OVER THE VALLEYS.
SUNDAY WILL BE A BLUSTERY AND COLD DAY WITH THE LONG-WAVE TROUGH
AXIS APPROACHING THE REGION. A SECONDARY COLD FRONT OR SFC TROUGH
WILL MOVE THROUGH WITH H850 TEMPS FALL TO -7C TO -10C. SOME SCT
SNOW AND RAIN SHOWERS ARE POSSIBLE. THE RAIN SHOWERS WILL BE MAINLY
WHERE THE BOUNDARY LAYER WARMS ENOUGH WITH TEMPS IN THEN 40-45F
RANGE. THE HIGHER POPS WILL BE NORTH AND WEST OF THE CAPITAL
DISTRICT AND THE MOHAWK RIVER VALLEY. SOME ADDITIONAL LIGHT SNOW
ACCUMS ARE POSSIBLE OVER THE WRN DACKS...ERN CATSKILLS...AND SRN
GREENS. HIGHS WILL BE MAINLY IN THE U30S TO L40S IN THE
VALLEYS...AND LOWER TO U30S OVER THE HIGHER TERRAIN...EXCEPT SOME
U20S IN THE SRN DACKS.
SUNDAY NIGHT INTO MONDAY...A COLD AIR MASS BUILDS IN FROM THE OHIO
VALLEY WITH SOME LAKE EFFECT SNOWFALL POSSIBLE BASED ON THE MEDIUM
RANGE GUIDANCE. LOCATIONS IN THE WRN DACKS...AND W-CNTRL MOHAWK
VALLEY MAY GET AT LEAST SOME LIGHT SNOW ACCUMS. THE REST OF THE FCST
AREA WILL REMAIN DRY...BUT COLD. THE LATEST GFS H850 TEMPS FALL TO
-10C TO -13C OVER THE FCST AREA. LOWS WILL BE IN THE MID AND U20S IN
THE VALLEYS...AND TEENS TO L20S OVER THE MTNS. HIGHS ON MONDAY
RANGE FROM THE U30S TO L40S IN THE VALLEY AREAS...AND U20S TO M30S
OVER THE MTNS.
MONDAY NIGHT INTO TUESDAY...THE LAKE EFFECT SNOWFALL SHOULD
TAPER...AS THE FLOW BECOMES MORE ZONAL. A WEAK DISTURBANCE IN THE
ZONAL FLOW COULD BRING A SLIGHT CHC OF SHOWERS TUE AFTERNOON WEST OF
THE MOHAWK VALLEY. THE ECMWF REMAINS DRY. TEMPS MODERATE TO
SEASONAL VALUES ON TUESDAY WITH SOME MID AND U40S IN THE CAPITAL
DISTRICT...TACONICS...MID HUDSON VALLEY...AND NW CT. U30S TO L40S
ARE COMMON NORTH AND WEST.
TUESDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE WILL RIDGE BACK IN OVER
THE NORTHEAST WITH FAIR AND DRY WEATHER FOR THE MID WEEK...AND
SEASONABLE TEMPS.
OVERALL...TEMPS WILL AVERAGE NEAR NORMAL WITH PCPN BELOW NORMAL IN
THE LONG TERM.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AN OCCLUDED FRONT WILL APPROACH FROM THE WEST LATER THIS
AFTERNOON...AND MOVE ACROSS THE TAF SITES THIS EVENING.
THROUGH 12Z/THU...MVFR CIGS...WHICH HAVE ALREADY OVERSPREAD THE
TAF SITES...SHOULD PERSIST. THE ONE EXCEPTION WILL BE AT
KPSF...WHERE CIGS SHOULD BE MAINLY IFR. THERE COULD BE SOME SPOTTY
DRIZZLE DEVELOPING TOWARD 12Z...WHICH COULD LEAD TO ADDITIONAL
MVFR VSBYS...AND BORDERLINE MVFR/IFR CIGS.
AFTER 12Z/THU...MVFR/IFR CIGS SHOULD TREND TO MAINLY IFR...WITH
VSBYS MAINLY IN THE MVFR RANGE THROUGH THE END OF THE TAF PERIOD
AT 06Z/FRI. OCCASIONAL IFR VSYBS COULD OCCUR DURING MODERATE/HEAVY
RAIN SHOWERS LATER THIS AFTERNOON INTO EARLY TONIGHT.
THE OCCLUDED FRONT IS EXPECTED TO PASS THROUGH THE TAF SITES
ROUGHLY IN THE 03Z-05Z/FRI TIME PERIOD. A PERIOD OF HEAVIER RAIN
SHOWERS AND GUSTY WINDS WILL IMMEDIATELY PRECEDE AND ACCOMPANY ITS
PASSAGE.
WINDS WILL REMAIN FROM THE SOUTHEAST TO SOUTH AT GENERALLY 8-12 KT
THROUGH MIDDAY...WITH OCCASIONAL GUSTS OF 12-22 KT...STRONGEST AT
KALB. THEN...WIND SPEEDS WILL INCREASE SLIGHTLY TO 10-15 KT THIS
AFTERNOON...WITH GUSTS OF 18-25 KT LIKELY...PERHAPS EVEN STRONGER
AT TIMES AT KALB...AND ALSO WHEN THE FRONT MOVES THROUGH EARLY
THURSDAY NIGHT. WHEN THE FRONT PASSES...THE WINDS WILL SHIFT INTO
THE SOUTHWEST TO WEST. BEHIND THE FRONT...SOUTHWEST TO WEST WINDS
WILL DECREASE SLIGHTLY...MAINLY INTO THE 5-10 KT RANGE.
LOW LEVEL WIND SHEAR WILL REMAIN LIKELY THROUGH AT LEAST SUNRISE
AT KGFL AND KPOU...WHERE SFC WINDS WILL BE SOMEWHAT LIGHTER FROM
THE SOUTHEAST TO SOUTH AT 8-12 KT...WHILE WINDS AROUND 2000 FT AGL
REMAIN FROM THE SOUTH AT 30-40 KT. AS SFC WINDS INCREASE AFTER
SUNRISE...THE THREAT FOR LOW LEVEL WIND SHEAR SHOULD DECREASE.
OUTLOOK...
FRIDAY - SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA...SHSN.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A SOAKING RAINFALL IS EXPECTED MAINLY THURSDAY AFTERNOON THROUGH
THURSDAY NIGHT. WE DID NOT ASSIGN A "WET FLAG" TO OUR NFDRS
SINCE THE BULK OF THE RAIN WILL NOT FALL UNTIL AFTER 100 PM
THURSDAY.
RAINFALL AMOUNTS SHOULD BE A QUARTER INCH OR MORE EVERYWHERE.
IT DRIES OUT FRIDAY WITH A NORTHWEST WIND 5- 15 MPH.
ANOTHER CLIPPER TYPE SYSTEM COULD BRING RAIN OR SNOW SHOWERS
SATURDAY NIGHT...ESPECIALLY NORTH AND WEST OF ALBANY. THERE
MIGHT BE SOME MINOR ACCUMULATIONS OF SNOW.
MUCH COLDER AIR WORKS IN ON GUSTY WINDS FOR THE LATER PORTION OF THE
WEEKEND.
&&
.HYDROLOGY...
A COLD FRONT WILL BRING A ROUND OF RAIN SHOWERS TO THE REGION
LATER THURSDAY INTO THURSDAY NIGHT.
THIS IS A PROGRESSIVE SYSTEM...SO IT WILL NOT LINGER TOO LONG.
IT DRIES OUT BY FRIDAY.
RAINFALL AMOUNTS LOOK TO BE HALF AN INCH TO AROUND AN INCH IN
THE VALLEYS...POSSIBLY UP TO TWO INCHES ACROSS THE HIGHER TERRAIN...
OF THE SOUTHERN GREENS AND BERKSHIRES.
THIS RAIN WILL PRODUCE WITHIN BANK RISES...MAYBE A FEW SPOTS
APPROACHING ACTION STAGE. NO FLOODING EXPECTED.
COOLER AND DRIER WEATHER WILL RETURN FRIDAY INTO THE FIRST HALF
OF THE WEEKEND. ANOTHER SYSTEM MAY BRING LIGHT PCPN IN THE FORM OF
RAIN/SNOW SHOWERS SATURDAY NIGHT INTO SUNDAY WITH LITTLE OR NO HYDROLOGICAL
IMPACTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/GJM
NEAR TERM...HWJIV/NAS
SHORT TERM...HWJIV/KL
LONG TERM...WASULA
AVIATION...KL
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV/KL/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1220 AM EST THU NOV 19 2015
.SYNOPSIS...
A WARM FRONT WILL WORK ACROSS OUR REGION TONIGHT...KEEPING
TEMPERATURES MILD UNDER A CANOPY OF INCREASING CLOUDS. SPOTTY
DRIZZLE WILL BREAK OUT EARLY THURSDAY...FOLLOWED BY HEAVIER
SHOWERS LATER IN THE DAY WHICH WILL BE AHEAD OF A COLD FRONT THAT
WILL CROSS OUR REGION THURSDAY NIGHT. COOLER DRIER AIR WILL FOLLOW
FOR FRIDAY... FOLLOWED BY EVEN COLDER AIR AND SOME SHOWERS OF RAIN
OR SNOW FOR LATER IN THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
CLOUDS AND SLOWLY INCREASING WINDS THROUGH THE EARLY MORNING
HOURS. SOME INDICATIONS OF SOME SPOTTY LIGHT RAIN AND DRIZZLE IN
SOME AREAS...SHOULD VERY GRADUALLY INCREASE IN COVERAGE TOWARD
DAYBREAK...BUT STILL JUST CHANCES. THE MORE WIDESPREAD RAIN IS
SEEN IN WESTERN NY AND WILL AFFECT OUR REGION THROUGH THE DAY.
TEMPERATURES HAVE REACHED THEIR LOWS IN THE UPPER 40S TO LOWER
50S...AND SLOWLY RISE THROUGH SUNRISE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
BY THURSDAY...OUR WHOLE AREA WILL BE IN A MOIST MILD AIR MASS
WITH A COLD FRONT RAPIDLY APPROACHING FROM THE WEST.
THIS IS THE SAME SYSTEM THAT PRODUCED QUITE AN ARRAY OF FOUL WEATHER
OUT WEST...INCLUDING SEVERE WEATHER AND EVEN BLIZZARD CONDITIONS.
NEITHER IS EXPECTED FOR US (INSTABILITY NOT THERE FOR ANY REAL
CONVECTION). A RUMBLE OF THUNDER IS CERTAINLY POSSIBLE BUT WITH
SHOWALTER VALUES >0 AND CAPE VALUES NEAR 0 J/KG WILL KEEP
ANY MENTION OF THUNDERSTORMS OUT OF THE GRIDS FOR NOW.
THAT SAID...WITH PWATS SOARING PAST AN INCH....TWO STANDARDS ABOVE
NORMAL. THE COMBINATION OF THIS MOISTURE...THE FRONT...SHORTWAVE
ENERGY AND OUR AREA COMING UNDER THE DIVERGENT AREA OF THE RR 100KT
NIGHT BY EVENING...ALL POINT TO ROUND OF SHOWERS...SOME CONTAINING
MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL.
WHAT IS A LITTLE DIFFERENT FROM PREVIOUS RUNS...THERE IS LESS OF TENDENCY FOR
A SECONDARY WAVE TO DEVELOP ALONG THE TRIPLE POINT...AS THERE WAS
IN SOME EARLIER RUNS. IT LOOKS LIKE A PROGRESSIVE SYSTEM...PRETTY MUCH
WHAT WE HAVE SEEN THIS AUTUMN.
A GUSTY SOUTH WIND WILL ENSUE ON THURSDAY...10-15 MPH...WITH GUSTS
25-35 MPH ACROSS PORTIONS OF THE HIGHER TERRAIN...AND EVEN
SOME SECTIONS OF THE CAPITAL REGION AND MOHAWK VALLEY. DURING
HEAVY SHOWERS...IT IS REMOTELY POSSIBLE THAT SOME GUSTS COULD EVEN
REACH A LITTLE HIGHER THAN THAN THAT...BUT JUST BRIEFLY.
THEREFORE...NO WIND HEADLINES WERE ASSIGNED WITH THIS PACKAGE.
THE ACTUAL COLD FRONT LOOKS TO MOVE ON THROUGH THURSDAY EVENING...
FOLLOWED BY HIGH PRESSURE BEGINNING TO BUILD IN BY EARLY FRIDAY.
IN FACT...THE SKY MIGHT ACTUALLY CLEAR BY DAYBREAK FRIDAY OR AT
LEAST PARTIALLY CLEAR.
BASED ON UPSTREAM TEMPERATURES WELL INTO THE 60S...WE WILL GO SLIGHTLY
HIGHER THAN ALL MACHINE GUIDANCE ON THURSDAY. LOOK FOR HIGHS LOWER TO MID
60S IN THE VALLEYS...MID OR UPPER 50S EVEN ACROSS THE HIGHER TERRAIN.
TURNING COOLER...BUT STILL ABOVE NORMAL THURSDAY NIGHT WITH LOWS
RANGING FROM THE UPPER 30S TO MID 40S.
FRIDAY SHOULD FEATURE AT LEAST PARTIAL SUNSHINE AS THE FLOW LOOKS TOO ANTI-
CYCLONIC FOR MUCH LAKE INDUCED CLOUDS (OUTSIDE OF THE ADIRONDACKS WHERE
UPSLOPE CLOUDS AND A FEW SHOWERS OF RAIN OR RAIN AND WET SNOW MIXED ARE
POSSIBLE).
HIGH TEMPERATURES WILL BE NOTICEABLY COOLER THAN THURSDAY...HIGHS NEAR 50
IN THE VALLEYS...LOWER TO MID 40S HIGHER TERRAIN...CLOSER TO 40
ACROSS THE ADIRONDACKS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE EXTENDED OPENS WITH A POTENT UPPER LEVEL TROUGH APPROACHING FROM
THE GREAT LAKES REGION AND THE MIDWEST. THE UPPER LEVEL TROUGH
TURNS NEGATIVELY TILTED ACCORDING TO LATEST GFS/ECMWF...AS THE SFC
CYCLONE LIFTS NORTHEAST ACROSS THE ERN GREAT LAKES REGION INTO SE
ONTARIO BY 12Z SUN. THERE IS ENOUGH MOISTURE WITH THE OCCLUDED
FRONT TO THE SYSTEM FOR A PERIOD OF RAIN SHOWERS TRANSITIONING TO
SNOW SHOWERS. THERE IS DECENT LIFT AND CONVERGENCE WITH THE
BOUNDARY. SOME LIGHT SNOW ACCUMULATIONS ARE POSSIBLE WITH A COATING
TO LESS THAN A HALF AN INCH IN THE VALLEY AREAS...AND AN INCH OR TWO
OVER THE HIGHER TERRAIN. THE LIGHT SNOW IS SUPPORTED FROM SOME OF
THE ENSEMBLES. THE LATEST GEFS PLUME DIAGRAM YIELDS ABOUT A TENTH OF
AN INCH OF SNOWFALL FOR ALBANY WITH PERHAPS A HALF DOZEN MEMBERS OR
SO. LOWS SAT NIGHT WILL RANGE FROM THE MID AND U20S OVER THE MTNS TO
U20S TO L30S OVER THE VALLEYS.
SUNDAY WILL BE A BLUSTERY AND COLD DAY WITH THE LONG-WAVE TROUGH
AXIS APPROACHING THE REGION. A SECONDARY COLD FRONT OR SFC TROUGH
WILL MOVE THROUGH WITH H850 TEMPS FALL TO -7C TO -10C. SOME SCT
SNOW AND RAIN SHOWERS ARE POSSIBLE. THE RAIN SHOWERS WILL BE MAINLY
WHERE THE BOUNDARY LAYER WARMS ENOUGH WITH TEMPS IN THEN 40-45F
RANGE. THE HIGHER POPS WILL BE NORTH AND WEST OF THE CAPITAL
DISTRICT AND THE MOHAWK RIVER VALLEY. SOME ADDITIONAL LIGHT SNOW
ACCUMS ARE POSSIBLE OVER THE WRN DACKS...ERN CATSKILLS...AND SRN
GREENS. HIGHS WILL BE MAINLY IN THE U30S TO L40S IN THE
VALLEYS...AND LOWER TO U30S OVER THE HIGHER TERRAIN...EXCEPT SOME
U20S IN THE SRN DACKS.
SUNDAY NIGHT INTO MONDAY...A COLD AIR MASS BUILDS IN FROM THE OHIO
VALLEY WITH SOME LAKE EFFECT SNOWFALL POSSIBLE BASED ON THE MEDIUM
RANGE GUIDANCE. LOCATIONS IN THE WRN DACKS...AND W-CNTRL MOHAWK
VALLEY MAY GET AT LEAST SOME LIGHT SNOW ACCUMS. THE REST OF THE FCST
AREA WILL REMAIN DRY...BUT COLD. THE LATEST GFS H850 TEMPS FALL TO
-10C TO -13C OVER THE FCST AREA. LOWS WILL BE IN THE MID AND U20S IN
THE VALLEYS...AND TEENS TO L20S OVER THE MTNS. HIGHS ON MONDAY
RANGE FROM THE U30S TO L40S IN THE VALLEY AREAS...AND U20S TO M30S
OVER THE MTNS.
MONDAY NIGHT INTO TUESDAY...THE LAKE EFFECT SNOWFALL SHOULD
TAPER...AS THE FLOW BECOMES MORE ZONAL. A WEAK DISTURBANCE IN THE
ZONAL FLOW COULD BRING A SLIGHT CHC OF SHOWERS TUE AFTERNOON WEST OF
THE MOHAWK VALLEY. THE ECMWF REMAINS DRY. TEMPS MODERATE TO
SEASONAL VALUES ON TUESDAY WITH SOME MID AND U40S IN THE CAPITAL
DISTRICT...TACONICS...MID HUDSON VALLEY...AND NW CT. U30S TO L40S
ARE COMMON NORTH AND WEST.
TUESDAY NIGHT INTO WEDNESDAY...HIGH PRESSURE WILL RIDGE BACK IN OVER
THE NORTHEAST WITH FAIR AND DRY WEATHER FOR THE MID WEEK...AND
SEASONABLE TEMPS.
OVERALL...TEMPS WILL AVERAGE NEAR NORMAL WITH PCPN BELOW NORMAL IN
THE LONG TERM.
&&
.AVIATION /05Z THURSDAY THROUGH MONDAY/...
MVFR CIGS ALREADY OCCURRING AT KPOU/KPSF...AND EXPECT MVFR CIGS TO
MOVE INTO KALB ND KGFL BEFORE MIDNIGHT. THEN MVFR CIGS AND
POSSIBLE MVFR VSBYS WILL OCCUR FOR THE REST OF THE NIGHT AS SOME
FOG OR DRIZZLE DEVELOPS ACROSS THE REGION. IFR CIGS ARE ALSO
POSSIBLE AT KPOU/KPSF LATE TONIGHT...ESPECIALLY AT KPSF WHERE THE
IFR CIGS COULD START AROUND 06Z.
MVFR/IFR CIGS WILL PERSIST INTO THE MORNING...BUT THE DRIZZLE AND
FOG WILL GIVE WAY TO MORE SHOWERY PCPN AS THE COLD FRONT
APPROACHES FROM THE WEST. EXPECT THE WIDESPREAD SHOWERS TO BEGINN
AROUND 15Z/16Z...WITH IFR CIGS AND MVFR VSBYS OCCURING AT ALL THE
TAF SITES THROUGH THE REST OF THE TAF PERIOD ENDING AT 00Z FRIDAY.
A SOUTH BREEZE WILL CONTINUE AT ALL THE TAF SITES THROUGH THE PERIOD.
THE WIND WILL AVERAGE 10KTS AT ALL THE TAF SITES...WITH SOME
HIGHER GUSTS POSSIBLE...ESPECIALLY LATER ON THURSDAY.
A COLD FRONT WILL CROSS THE TAF SITES BUT NOT UNTIL THURSDAY NIGHT.
LOOK FOR MVFR AND POSSIBLY EVEN IFR CONDITIONS HEADING INTO
THURSDAY NIGHT.
OUTLOOK...
FRIDAY - SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA...SHSN.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A SOAKING RAINFALL IS EXPECTED MAINLY THURSDAY AFTERNOON THROUGH
THURSDAY NIGHT. WE DID NOT ASSIGN A "WET FLAG" TO OUR NFDRS
SINCE THE BULK OF THE RAIN WILL NOT FALL UNTIL AFTER 100 PM
THURSDAY.
RAINFALL AMOUNTS SHOULD BE A QUARTER INCH OR MORE EVERYWHERE.
IT DRIES OUT FRIDAY WITH A NORTHWEST WIND 5- 15 MPH.
ANOTHER CLIPPER TYPE SYSTEM COULD BRING RAIN OR SNOW SHOWERS
SATURDAY NIGHT...ESPECIALLY NORTH AND WEST OF ALBANY. THERE
MIGHT BE SOME MINOR ACCUMULATIONS OF SNOW.
MUCH COLDER AIR WORKS IN ON GUSTY WINDS FOR THE LATER PORTION OF THE
WEEKEND.
&&
.HYDROLOGY...
A COLD FRONT WILL BRING A ROUND OF RAIN SHOWERS TO THE REGION
LATER THURSDAY INTO THURSDAY NIGHT.
THIS IS A PROGRESSIVE SYSTEM...SO IT WILL NOT LINGER TOO LONG.
IT DRIES OUT BY FRIDAY.
RAINFALL AMOUNTS LOOK TO BE HALF AN INCH TO AROUND AN INCH IN
THE VALLEYS...POSSIBLY UP TO TWO INCHES ACROSS THE HIGHER TERRAIN...
OF THE SOUTHERN GREENS AND BERKSHIRES.
THIS RAIN WILL PRODUCE WITHIN BANK RISES...MAYBE A FEW SPOTS
APPROACHING ACTION STAGE. NO FLOODING EXPECTED.
COOLER AND DRIER WEATHER WILL RETURN FRIDAY INTO THE FIRST HALF
OF THE WEEKEND. ANOTHER SYSTEM MAY BRING LIGHT PCPN IN THE FORM OF
RAIN/SNOW SHOWERS SATURDAY NIGHT INTO SUNDAY WITH LITTLE OR NO HYDROLOGICAL
IMPACTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/GJM
NEAR TERM...HWJIV/NAS
SHORT TERM...HWJIV/KL
LONG TERM...WASULA
AVIATION...KL
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV/KL/WASULA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
344 PM EST THU NOV 19 2015
.SYNOPSIS...
20Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN AMPLIFIED UPPER
LEVEL PATTERN IN PLACE OVER THE CONUS...HIGHLIGHTED BY A BROAD
NEGATIVELY-TILTED LONGWAVE TROUGH. THIS TROUGH IS ANCHORED BY A
CLOSED LOW FEATURE SPINNING OVER THE UPPER MIDWEST. MOISTURE PLUME
ASSOCIATED WITH THE SOUTHERN STREAM JET IS WELL DEFINED ON WV
IMAGERY CROSSING THE GULF OF MEXICO AND OVER THE FLORIDA
PENINSULA. BEEN PLAYING CATCH-UP WITH THE FORECAST ALL DAY WITH
THIS PATTERN AS THE MODELS HAVE BEEN NOT HANDLING CERTAIN FEATURES
VERY WELL. SAW THE DEVELOPMENT OF A LEAF-CLOUD FEATURE OVER THE
FLORIDA PANHANDLE /NORTH-CENTRAL GULF OF MEXICO WITHIN THE
SOUTHERN STREAM MOISTURE PLUME THIS MORNING. THIS FEATURE IS THE
RESULT OF THE INTERACTION OF PASSING SHORTWAVE ENERGY (MOST
DEFINED ABOVE 500MB) WITH THE LOWER LEVEL FRONTAL BOUNDARY. THIS
CYCLOGENESIS CONTINUES TO NOT BE WELL REPRESENTED IN THE ENSEMBLE
GUIDANCE AND HENCE THE MODELS ARE GENERALLY TOO DRY AND HAVING
DIFFICULTY WITH THE HIGHER COVERAGE OF CONVECTION OVER THE
NORTHEAST GULF/NORTHERN FLORIDA.
FORECAST NOW HAS CATEGORICAL POPS AT 100% FOR THE ENTIRE NATURE
COAST WITH LIKELY/CATEGORICAL POPS DOWN EVEN INTO THE TAMPA BAY
AREA. THE SURFACE LOW DEVELOPMENT HAS SLOWED THE SOUTHWARD
PROGRESSION OF THE FRONT/BOUNDARY...AND THIS WILL ALLOW THE
CONTINUED CONVECTION OVER THE EASTERN GULF TO PROGRESS INLAND
ACROSS THE FLORIDA WEST COAST AS FAR SOUTH AS TAMPA BAY/MANATEE
COUNTY EARLY THIS EVENING.
SOUTH AND EAST OF TAMPA BAY...NOW SEEING DEVELOPMENT OF MORE
DIURNAL TYPE SCT SHOWERS WHICH SHOULD CONTINUE (AN EVEN INCREASE
IN COVERAGE SOMEWHAT) THROUGH THE MIDDLE EVENING HOURS.
HOWEVER...NOT EXPECTING ANY ORGANIZED OR LONG LASTING TYPE OF
RAINFALL FOR THIS PORTION OF THE FORECAST AREA.
&&
.SHORT TERM (TONIGHT THROUGH FRIDAY)...
TONIGHT... SHORTWAVE ENERGY PASSES OFF TO THE NORTHEAST ALLOWING
WHATEVER FRONTAL WAVE EXISTS TO OUR NORTH TO EXIT AND SWING THE
COLD FRONT DOWN THE PENINSULA. THIS PROGRESSION WILL SLOWLY
DECREASE RAIN CHANCES TO THE NORTH OF THE 1-4 CORRIDOR...WHILE AT
LEAST SCATTERED SHOWERS CONTINUE IN THE FORECAST FOR THE SOUTHERN
HALF OF THE AREA. BY DAWN THE FRONT LOOKS TO HAVE BECOME QUASI-
STATIONARY OVER SOUTH FLORIDA. ENOUGH DRY AIR ALOFT IS FORECAST BY
MOST GUIDANCE MEMBERS TO HAVE ADVECTED SOUTHWARD TO HOPEFULLY END
RAIN CHANCES NORTH OF TAMPA BAY BY DAWN. DESPITE THE COLD FRONTAL
PASSAGE DURING THE OVERNIGHT FOR MOST SPOTS...LOW TEMPERATURES
WILL REMAIN ABOVE NORMAL FOR MID NOVEMBER...RANGING FROM AROUND 60
IN THE FAR NORTH TO THE MID 60S/LOW 70S ELSEWHERE.
FRIDAY...RAIN CHANCES LOOK TO REMAIN VERY LOW TO THE NORTH OF THE
I-4 CORRIDOR THROUGHOUT FRIDAY AS DRY AIR ALOFT CONTINUE TO MOVE
DOWN FROM THE NORTH. AS ONE TRAVELS SOUTH FROM I-4...AVAILABLE
MOISTURE AND CLOSER PROXIMITY TO THE FRONTAL FORCING/CONVERGENCE
OVER SOUTH FLORIDA WILL INCREASE SHOWER CHANCES. THE LACK OF ANY
SUBSTANTIAL UPPER LEVEL SUPPORT SHOULD KEEP THE SHOWERS SCATTERED
WITH GENERALLY LIGHT QPF...HOWEVER...WOULD NOT ANTICIPATE MUCH IN
THE WAY OF SUN ON FRIDAY FROM THE I-4 CORRIDOR SOUTHWARD. A RATHER
CLOUDY PERIOD IS IN THE FORECAST...AND THAT TREND LOOKS TO
CONTINUE INTO THE UPCOMING WEEKEND...ALONG WITH HIGHER RAIN
CHANCES SURGING BACK NORTHWARD ON SATURDAY. MORE ON THE WEEKEND
FORECAST WITHIN THE LONG TERM DISCUSSION BELOW.
&&
.LONG TERM (FRIDAY NIGHT-THURSDAY)...
THE UPCOMING WEEKEND LOOKS TO BE ON THE WET SIDE BEFORE WE DRY UP
AND COOL OFF FOR EARLY NEXT WEEK. IN FACT...WE SHOULD SEE A COUPLE
OF DAYS OF BELOW-NORMAL TEMPERATURES BEFORE FINALLY GETTING
CLOSER TO NORMAL FOR THE MIDDLE PART OF THE WEEK.
AS FAR AS OUR WEEKEND WEATHER...RAIN CHANCES WILL BE ON THE RISE
THROUGH SATURDAY AND REMAIN IN THE CHANCE TO LIKELY RANGE THROUGH
SUNDAY AS UPPER-LEVEL SHORTWAVE ENERGY MOVES ACROSS THE GULF AND
THEN THE STATE THROUGH THE WEEKEND. AT THE SURFACE...THE STALLED
FRONTAL BOUNDARY ACROSS SOUTH FLORIDA WILL BE IN PLACE AND BOTH THE
GFS AND THE ECMWF TRY TO CLOSE OFF A LOW TO OUR NORTHEAST ON SUNDAY.
SEEING SOME MODEL DIFFERENCES AS FAR AS TIMING TO CLEAR EVERYTHING
OUT...WITH THE ECMWF A BIT ON THE SLOW SIDE. EITHER WAY...IT LOOKS
LIKE WE COULD STILL BE DEALING WITH SOME SHOWER ACTIVITY SUNDAY
NIGHT SO WILL LEAVE CHANCE POPS IN THE FORECAST.
WE SHOULD FINALLY CLEAR OUT DURING THE DAY ON MONDAY AS A FRONT
MOVES THROUGH AND THE COOLEST AND DRIEST AIR MASS WE HAVE SEEN SO
FAR THIS SEASON BEGINS TO MOVE INTO THE AREA. HIGH PRESSURE WILL
SETTLE INTO THE SOUTHEAST FOR MONDAY AND TUESDAY...WITH TEMPERATURES
BELOW NORMAL FOR BOTH DAYS. TUESDAY LOOKS TO BE THE COOLEST MORNING
THIS WEEK WITH LOWS IN THE LOWER 40S TO MID 50S. TEMPERATURES WILL
MODERATE CLOSER TO NORMAL VALUES FOR WEDNESDAY AND THURSDAY AS THE
HIGH SHIFTS NORTHEAST AND OUR WINDS BECOME MORE NORTHEASTERLY.
&&
.AVIATION...
VFR/MVFR CIGS CONTINUE ACROSS THE REGION THIS AFTERNOON. THE MOST
WIDESPREAD SHOWERS/RAINFALL IS NORTH OF THE TERMINALS...BUT RAIN
CHANCES WILL BE INCREASING FOR KPIE/KTPA/KLAL OVER THE NEXT
SEVERAL HOURS. TONIGHT...PERIODS OF MVFR CIGS/VIS LOOK PROBABLE
FOR ALL TERMINALS AS A WEAK COLD FRONT SETTLES SOUTH ACROSS THE
REGION.
&&
.MARINE...
A WEAKENING COLD FRONT SETTLES SOUTHWARD THROUGH THE EASTERN GULF
OF MEXICO TONIGHT. THIS FRONT WILL STALL OVER SOUTH FLORIDA BY
FRIDAY MORNING. A WEAK WAVE OF LOW PRESSURE NOW LOOKS TO RIDE
ALONG THIS FRONT AND THROUGH THE EASTERN GULF DURING THE UPCOMING
WEEKEND. IF THIS TREND CONTINUES...THE CHANCES FOR MORE WIDESPREAD
RAINFALL SATURDAY AND SUNDAY WILL BE INCREASING IN FUTURE
FORECASTS. HIGH PRESSURE WILL THEN BUILD IN FROM THE NORTH IN THE
WAKE OF THIS LOW LATE SUNDAY AND THROUGH THE EARLY PORTION OF NEXT
WEEK. MARINERS CAN EXPECT CAUTIONARY TO ADVISORY LEVEL NORTHEAST
FLOW ACROSS THE EASTERN GULF OF MEXICO DURING THE EARLY PORTION OF
NEXT WEEK.
&&
.FIRE WEATHER...
A WEAK COLD FRONT WILL CROSS THROUGH THE AREA TONIGHT AND STALL
OVER SOUTH FLORIDA ON FRIDAY. BEST CHANCE FOR SHOWERS WILL SINK
SOUTH WITH THE FRONT AND BE GENERALLY SOUTH OF THE I-4 CORRIDOR
FOR FRIDAY. ALTHOUGH SOME DRIER AIR WILL ARRIVE OVER THE NATURE
COAST...RELATIVE HUMIDITY VALUES ARE EXPECTED TO REMAIN ABOVE
CRITICAL LEVELS. HOWEVER...HIGH DISPERSION INDICES ARE FORECAST
ON FRIDAY FOR THE NATURE COAST ZONES. IT IS BECOME MORE LIKELY
THAT A WIDESPREAD RAIN EVENT WILL OCCUR ACROSS MUCH OF THE
REGION THIS WEEKEND...WHICH WILL PREVENT ANY FIRE WEATHER
CONCERNS.
FOG POTENTIAL...PATCHY FOG WILL BE POSSIBLE EACH NIGHT THROUGH
SUNDAY MORNING...HOWEVER NO SIGNIFICANT OR WIDESPREAD VISIBILITY
REDUCTIONS ARE EXPECTED THROUGH THE FORECAST PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 71 82 70 81 / 60 20 20 70
FMY 72 84 71 82 / 40 50 40 60
GIF 70 81 68 81 / 50 30 20 60
SRQ 70 82 70 81 / 50 30 30 70
BKV 67 80 66 82 / 60 20 10 60
SPG 71 82 70 80 / 60 20 20 70
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...BEACH HAZARDS STATEMENT THROUGH MONDAY EVENING FOR COASTAL
SARASOTA-PINELLAS.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/FIRE WEATHER...14/MROCZKA
LONG TERM...05/CARLISLE
MARINE...14/MROCZKA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1103 AM EST THU NOV 19 2015
.UPDATE...
15Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN AMPLIFIED UPPER LEVEL
PATTERN IN PLACE OVER THE CONUS...HIGHLIGHTED BY A BROAD
NEGATIVELY-TILTED LONGWAVE TROUGH. THIS TROUGH IS ANCHORED BY A
CLOSED LOW FEATURE SPINNING OVER THE UPPER MIDWEST. MOISTURE PLUME
ASSOCIATED WITH THE SOUTHERN STREAM JET IS WELL DEFINED ON WV
IMAGERY CROSSING THE GULF OF MEXICO AND OVER THE FLORIDA
PENINSULA. IN THE PAST FEW HOURS HAVE SEEN THE DEVELOPMENT OF
LEAF-CLOUD FEATURE OVER THE FLORIDA PANHANDLE/NORTH-CENTRAL GULF
OF MEXICO WITHIN THIS MOISTURE PLUME. THIS FEATURE APPEARS TO BE
ASSOCIATED WITH THE INTERACTION OF PASSING SHORTWAVE ENERGY (MOST
DEFINED ABOVE 500MB) WITH THE LOWER LEVEL FRONTAL BOUNDARY. THIS
CYCLOGENESIS IS NOT BEING REPRESENTED WELL IN THE ENSEMBLE
GUIDANCE AND HENCE THE MODELS ARE GENERALLY NOT HANDLING THE
HIGHER COVERAGE OF CONVECTION OVER THE NORTHEAST GULF VERY WELL.
AS THIS FRONTAL WAVE MOVES EAST IT HAS BECOME OBVIOUS THAT A
DEVIATION FROM THE GUIDANCE SOLUTIONS IS NECESSARY AND HAVE MADE
SOME SIGNIFICANT FORECAST UPDATES TO OUR NORTHERN ZONES IN TERMS
OF RAINFALL POPS AND QPF THROUGH THE REMAINDER OF THE DAY AS IT
LOOKS TO BE RATHER WET TO THE NORTH OF BROOKSVILLE.
WATCHING NEW GUIDANCE ARRIVAL AND RADAR/WV TRENDS CLOSELY TO
DETERMINE IF HIGHER POPS WILL BE REQUIRED LATER TODAY FURTHER
SOUTH...DOWN INTO SUMTER/HERNANDO/PASCO...MAYBE EVEN THE TAMPA BAY
AREA. JUST HOW FAR SOUTH THE MORE ORGANIZED CONVECTION EXPANDS
WILL BE DEPENDENT ON THE SPEED THAT THE FRONTAL WAVE PASSES BY.
THE SLOWER THE PASSAGE THE FURTHER SOUTH THE FRONT WILL HAVE
PROGRESSED. AT THE SAME TIME...ANY SURFACE LOW DEVELOPMENT WILL
SLOW THE SOUTHWARD PROGRESSION OF THE BOUNDARY. SO...ITS A
DIFFICULT FORECAST SOUTH OF BROOKSVILLE THROUGH 00Z.
SOUTH OF TAMPA BAY...MAINLY LOOKING FOR THE DEVELOPMENT OF MORE
DIURNAL TYPE SCT SHOWERS INTO THE LATER AFTERNOON/EVENING
HOURS...BUT NO ORGANIZED OR LONG LASTING TYPE OF RAINFALL THROUGH
THE REST OF THE DAY.
TONIGHT...
SHORTWAVE ENERGY PASSES OFF TO THE NORTHEAST WITH TIME ALLOWING
WHATEVER FRONTAL WAVE THERE IS TO EXIT AND SWING THE COLD FRONT
DOWN THE PENINSULA. THIS PROGRESSION WILL SLOWLY DECREASE RAIN
CHANCES TO THE NORTH OF THE 1-4 CORRIDOR...WHILE AT LEAST
SCATTERED SHOWERS CONTINUE IN THE FORECAST FOR THE SOUTHERN HALF
OF THE AREA. BY DAWN THE FRONT LOOKS TO HAVE BECOME QUASI-
STATIONARY OVER SOUTH FLORIDA. ENOUGH DRY AIR ALOFT LOOKS TO HAVE
ADVECTED SOUTHWARD TO BASICALLY END RAIN CHANCES NORTH OF TAMPA
BAY FOR FRIDAY MORNING...BUT WILL BE INCREASING POPS THE FURTHER
SOUTH ONE TRAVELS FROM THE I-4 CORRIDOR...IN CLOSER PROXIMITY TO
THE STALLED FRONTAL FOCUS.
&&
.AVIATION...
VFR/MVFR CIGS ACROSS THE REGION LATE THIS MORNING. MOST OF THE
RAINFALL IS NORTH OF THE TERMINALS. SOME INDICATIONS THAT MORE
NUMEROUS SHOWERS MAY BECOME NECESSARY FOR KTPA/KPIE LATER
TODAY...AND WILL BE MONITORING RADAR TRENDS CLOSELY.
TONIGHT...PERIOD OF MVFR CIGS/VIS LOOK PROBABLE FOR ALL TERMINALS
AS A WEAK COLD FRONT SETTLES SOUTH ACROSS THE REGION. A PERIOD OF
IFR IS NOT OUT OF THE QUESTION FOR KLAL/KPGD...BUT WILL KEEP OUT
OF CURRENT TAF PACKAGE UNTIL CONFIDENCE INCREASES.
&&
.MARINE...
A WEAKENING COLD FRONT WILL APPROACH THE WATERS FROM THE
NORTHWEST TODAY AND SETTLE THROUGH THE EASTERN GULF OF MEXICO
TONIGHT. THIS FRONT WILL STALL OVER SOUTH FLORIDA DURING FRIDAY.
A WEAK WAVE OF LOW PRESSURE NOW LOOKS TO RIDE ALONG THIS FRONT
AND THROUGH THE EASTERN GULF DURING THE UPCOMING WEEKEND. IF THIS
TREND CONTINUES...THE CHANCES FOR MORE WIDESPREAD RAINFALL
SATURDAY AND SUNDAY WILL BE INCREASING IN FUTURE FORECASTS. HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTH IN THE WAKE OF THIS
LOW LATE SUNDAY AND THROUGH THE EARLY PORTION OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 83 71 82 67 / 40 40 20 20
FMY 86 72 84 68 / 40 50 50 40
GIF 84 69 80 65 / 60 50 20 20
SRQ 83 71 83 69 / 40 40 20 30
BKV 84 67 81 64 / 50 40 20 20
SPG 83 71 81 70 / 40 40 20 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...BEACH HAZARDS STATEMENT UNTIL 10 PM EST THIS EVENING FOR
COASTAL SARASOTA-PINELLAS.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE...MROCZKA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
333 AM EST THU NOV 19 2015
.DISCUSSION...
...INCREASED RAIN CHANCES THRU TONIGHT WITH SLIGHT CHANCE OF
LIGHTNING STORMS...
TODAY-TONIGHT...COOL FRONT IN THE FLORIDA PANHANDLE WILL MOVE SLOWLY
EAST IN TANDEM WITH SLOWLY RETREATING DEEP LAYER RIDGE JUST OFF THE
EASTERN SEABOARD. ANOMALOUSLY MOIST AIR MASS AHEAD OF THE FRONT
AND SOME DIVERGENCE ALOFT SHOULD PROVIDE FOR HIGH POPS EVEN THOUGH
THE LOW LEVEL CONVERGENCE WILL BE WEAKENING.
LATEST SATELLITE SHOWS THAT MULTI-LAYERED CLOUD BAND CLOSE TO THE
FRONT WILL HOLD BACK ENOUGH FOR MODEST SURFACE HEATING THIS MORNING
ACROSS THE LOCAL AREA. THIS HEATING SHOULD ALLOW FOR AN EAST COAST
SEA BREEZE WHICH WILL ACT AS THE INITIAL FOCUS FOR SCATTERED SHOWERS
AND ISOLATED LIGHTNING STORMS BY EARLY-MID AFTERNOON. THEN AS
WEAK PRE FRONTAL CONVERGENCE SLIDES INTO THE AREA...CONVECTION
SHOULD INCREASE INTO EARLY EVENING. MOS POPS ARE REALLY HIGH AT
60-80 PERCENT TODAY AND 60-90 PERCENT TONIGHT. THINK THAT THE BULK
OF THIS WILL BE IN THE MID-LATE AFTERNOON AND EVENING. DECIDED TO
JUST STICK WITH THE PREVIOUS POPS WHICH ARE 60-70 PERCENT
TODAY/TONIGHT. RAINFALL AMOUNTS EXPECTED TO AVERAGE A QUARTER TO
HALF INCH...BUT A FEW STORMS COULD DUMP A QUICK ONE OR TWO INCHES.
FRI...SURFACE BOUNDARY EXPECTED TO BECOME QUASI-STATIONARY OVER
SOUTHERN FLORIDA DURING THE DAY WITH SOME MID-LEVEL DRY AIR
FILTERING IN OVERHEAD. BEST MOISTURE WILL EXIST ACROSS THE SOUTHERN
THIRD OF THE CWA...THUS HIGHEST POPS RESIDE OVER THIS AREA. GIVEN THE
BOUNDARY`S LACK OF FORWARD MOMENTUM BY THIS TIME...AND ITS WEST-EAST
ORIENTATION...COOL AND DRY AIR ADVECTION LOOKS TO BE UNIMPRESSIVE
DURING THE DAY...ESPECIALLY CONSIDERING WINDS ARE EXPECTED TO VEER
ONSHORE THROUGH THE DAY.
WEEKEND...EXPECTING A RESURGENCE OF MOISTURE ACROSS THE CENTRAL
AND SOUTHERN HALF OF THE PENINSULA AS WEAK LOW PRESSURE TRIES TO
ORGANIZE ALONG THE TAIL END OF THE FRONT OVER THE EASTERN GULF.
GUIDANCE...EACH WITH THEIR VARYING DEGREES OF DEVELOPMENT...INCREASE
MOISTURE AND RAIN CHANCES DURING THE DAY ON SATURDAY AND EVEN INTO
SUNDAY IF YOU WERE TO BELIEVE THE ECMWF. THIS FORECAST CYCLE WILL
AIM FOR A COMPROMISE AMONGST THE GLOBAL MODELS...ULTIMATELY KEEPING
RAIN CHANCES AROUND THROUGH SUNDAY BEFORE A REINFORCING FRONT STARTS
TO DRY THINGS OUT LATE SUNDAY OR EARLY MONDAY.
EARLY NEXT WEEK...GIVEN THE VARIOUS MODEL DISCREPANCIES LATE IN THE
WEEKEND INTO MONDAY...CONFIDENCE IS LOW ON THE EXACT TIMING OF THE
REINFORCING SHOT OF COOL CONTINENTAL AIR FROM THE NORTH. REGARDLESS
OF THE TIMING...DRY AIR ADVECTION AND COOLING WILL BE MORE IMPRESSIVE
BEHIND THIS SECOND BOUNDARY. FOR AREAS CLOSE TO THE
COAST...MODIFICATION OFF THE ATLANTIC WILL BE QUICK TO OCCUR AS
WINDS VEER ONSHORE.
&&
.AVIATION...
SCATTERED SHOWERS HAVE BEEN RUNNING UP THE TREASURE AND
SPACE COASTS OVERNIGHT AND PRODUCING BRIEF DOWNPOURS WITH IFR
CONDITIONS. THIS IS A SIGN OF WHAT IS AHEAD THIS AFTERNOON AS THE
VERY MOIST AIR MASS UNDERGOES DESTABILIZATION AND WEAK PRE FRONTAL
CONVERGENCE ENTERS THE MIX. THE HRRR MODEL HAS BEEN HOLDING OFF
DAYTIME CONVECTIVE INITIATION UNTIL EARLY AFTERNOON. WOULD EXPECT
COVERAGE TO THEN INCREASE THROUGH EARLY EVENING. WITH THE VERY
MOIST AIR MASS...MOST SHOWERS WILL PRODUCE BRIEF IFR. ISOLATED
STORMS COULD HAVE IFR-MVFR FOR AN HOUR OR MORE.
&&
.MARINE...
TODAY-TONIGHT...LATEST WINDS AT BUOY 41009 WERE STILL AROUND 20
KNOTS WITH SEAS NEAR 8 FEET. ALL GUIDANCE WEAKENS THE PRESSURE
GRADIENT STEADILY DURING THE DAY. STILL...WILL NEED TO HOLD ONTO
AN ADVISORY EARLY THIS MORNING OFFSHORE...WITH EXERCISE CAUTION
STATEMENT NEAR SHORE. BY AFTERNOON SOUTHERLY WINDS WILL DROP OFF
TO 10-15 KNOTS AS SEAS DIMINISH TO 5-6 FEET. SCATTERED SHOWERS AND
ISOLATED STORMS SHOULD START TO MOVE OFFSHORE BY MID-LATE AFTERNOON.
WITH SLOW MOVING FRONTAL BOUNDARY DROPPING THROUGH THE NORTHERN
WATERS TONIGHT...THE SHOWERS/ISOLATED STORMS ARE EXPECTED TO
PERSIST MUCH OF THE NIGHT.
FRI...SURFACE BOUNDARY WILL MOVE THROUGH THE COASTAL WATERS
THROUGH THE MORNING HOURS ON FRIDAY BEFORE STALLING OVER SOUTH
FLORIDA. SURFACE WINDS WILL RESPOND BY VEERING FROM A LIGHT
TO GENTLE W/NW BREEZE EARLY FRI MORNING...TO A GENTLE TO MODERATE
NORTHERLY BREEZE BY MIDDAY...THEN A MODERATE E/NE BREEZE AFTER
SUNSET.
SAT-TUE...PRESSURE GRADIENT RELAXES DURING ON SATURDAY WITH A GENTLE
EAST/SOUTHEAST BREEZE EXPECTED. WIND FORECAST REMAINS A BIT TRICKY
SATURDAY NIGHT INTO SUNDAY AS WEAK LOW PRESSURE TRIES TO ORGANIZE
OVER THE GULF BEFORE MOVING EAST OVER THE PENINSULA. ONCE THE LOW
PRESSURE MOVES EAST OF THE STATE..LATE SUNDAY OR EARLY MONDAY...SEAS
AND NORTHERLY WINDS WILL BUILD QUICKLY BEHIND A REINFORCING FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 84 68 78 69 / 70 60 20 30
MCO 85 69 80 68 / 70 60 20 20
MLB 85 72 81 72 / 60 70 30 30
VRB 85 71 81 72 / 60 70 40 30
LEE 84 67 79 66 / 70 60 20 20
SFB 84 69 79 68 / 70 60 20 20
ORL 85 70 80 69 / 70 60 20 20
FPR 85 71 81 71 / 60 70 40 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR
FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 20-60 NM-
SEBASTIAN INLET TO JUPITER INLET 20-60 NM-VOLUSIA-BREVARD
COUNTY LINE TO SEBASTIAN INLET 20-60 NM.
&&
$$
SHORT TERM...LASCODY
LONG TERM....ULRICH
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
841 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 830 PM CST FRI NOV 20 2015
Forecast looking on track for the rest of this evening with the
rain slowly spreading into east central IL, with a changeover
to snow occurring over our far northern counties.
00z ILX sounding continues to indicate a very dry air mass in
place below 700 mb early this evening. Strong low and mid level
warm advection pattern ahead of the main upper level wave has
produced this lead band of rain with isolated convection seen over
parts of east central Missouri. Forcing aloft is sufficient enough
to moisten the low levels rather quickly this evening producing
some significant evaporative cooling as the temp-dew point spreads
were rather large this afternoon. The rain has gone over to snow
in Altona in far northern Knox county with a temperature there of
32 degrees, with most other locations to the south still well in
the 40s. In fact, the latest surface analysis showing the dew
points over parts of west central and central Illinois were rising
into the lower 30s over the past few hours.
Quick look at the 00z Nam-Wrf suggests the strong forcing/lift
associated with the amplified 500 mb trof will be during the
morning hours of Saturday. Most of the short term model soundings
were rather warm in the low levels of the atmosphere thru about
09z before the stronger forcing coincides with the deeper moisture
to produce a steady precip pattern over our area. Low level flow
until then will be out of a southeast to east direction, not very
conducive to a quick changeover to snow. However, after 09z, the
RAP soundings suggest winds back more into a northeast to north
direction which would suggest a quick change to snow further east
and southeast of the IL River valley. That is what is currently
reflected in the ZFP, so other than some minor tweaks to precip
timing and with hourly temperatures, no major changes being made
to the grids. Have already sent out an update earlier this evening
to address the precip timing out west this evening, so no additional
ZFP update will be needed at this time.
&&
.SHORT TERM...(Tonight)
ISSUED AT 300 PM CST FRI NOV 20 2015
20z/2pm surface analysis continues to show a ridge of high pressure
extending from the Upper Midwest into the Ohio River Valley, while a
1010mb low gets organized over south-central Nebraska. Light snow
has developed in advance of the low as far east as central Iowa:
however, it is having a hard time spreading further eastward due to
a dry airmass in place beneath the ridge axis. Current surface
dewpoints across the KILX CWA are only in the teens and 20s, and
forecast soundings suggest the airmass will only slowly moisten from
the top-down as the day progresses. 19z run of the Rapid Refresh
model shows light precipitation arriving in the Illinois River
Valley between 6 and 9pm, then gradually spreading eastward to the
Indiana border toward dawn Saturday. If this solution pans out,
much of the Wabash River Valley will remain dry through the entire
night. Precipitation type will be a bit tricky, as surface
temperatures will initially be warm enough to support rain. However,
as evaporative cooling of the dry mid/low levels takes place, a
transition from rain to snow will occur from mid evening through the
overnight hours. Based on NAM/Rapid Refresh soundings, will include
a mix of rain/snow as far east as a Bloomington to Springfield line
by midnight...then further south/east to a Danville to Taylorville
line by dawn. The mixed precip will become all snow along/north of
a Rushville to Bloomington line overnight. Snowfall totals through
12z Saturday will range from around 1 inch along a Rushville to
Bloomington line...to 2 to 3 inches north of the Peoria area. Since
this will be the first snow of the upcoming winter season, decided
to add another row of counties to the Winter Weather Advisory to
include Fulton, Tazewell, and McLean.
.LONG TERM...(Saturday through Friday)
ISSUED AT 300 PM CST FRI NOV 20 2015
Complicated forecast continuing into tomorrow morning with the
winter storm continuing the snow fall roughly north of a line from
Rushville to Champaign...ending from west to east by noon. Areas in
central and southeastern Illinois will see a slow end to the rain as
well as colder air moves in behind the system. Whereas the bulk of
the snow will fall before 6 am, some additional accumulations will
fall through noon, particularly along and north of I-74 from
Galesburg to Bloomington/Normal. Winds will pick up out of the
northwest becoming somewhat breezy and dropping the temperatures
through the afternoon. Some blowing snow will be possible,
especially in open areas...but the majority of the snow will be
heavy and wet early on, and affected by partial melting.
Cold air moving into the region overnight with clearing skies, and
by Sunday morning, temperatures will drop into the single digits and
teens. Brisk winds in the morning will result in wind chills
dropping to -3C to 11C range. Sundays high temperatures will
struggle into the 30s, with areas in the north and nearer to any
remaining snow will have a hard time reaching the freezing mark. But
Sunday night the high pressure ridge axis will drift to the east and
southerly flow will kick back in, ushering warmer air into the
region and starting to slowly erode any remaining snow.
Southwesterly flow aloft assists the warm up with the next system
digging into the desert SW and amplifying the pattern across the
CONUS. Big question for the first part of the week will be how much
of the snow remains in the northern tier of the state. For now,
temperatures start on a warming trend that will continue through the
holiday. By Wednesday and Thursday, temps are above freezing through
the overnight as well and the next system lays out a boundary across
the region, providing a focus for plenty of rain in the Midwest in
time for holiday travel. So far the models are keeping rain
prolonged through Thanksgiving and into Friday. Cold air will move
in again behind the system, with chilly temperatures back for next
weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
ISSUED AT 525 PM CST FRI NOV 20 2015
Timing of precip into the forecast area and initial affects
on cigs the main challenge this evening, and then precip
type and changeover late tonight as a storm system shifts
south of the area. Rain has started over far western Il
and expect this light rain to gradually work its way
east this evening. However, forecast soundings continue
to show a very dry atmosphere in place in the low levels
so that will initially retard the eastward push to the
rain actually reaching the ground but will include at
least a VCSH across our west early this evening with the
main threat for rain and snow coming in later this evening
up in PIA and after midnight in BMI. RUC forecast soundings
continue to suggest the changeover to snow in PIA around
the midnight hour and between 08-10z at BMI with areas further
south seeing mostly rain until Saturday morning.
With the strongest lift moving across our area tomorrow morning
there looks to be a period of IFR cigs and vsbys in snow across
the north, with a changeover to light snow further south as our
easterly winds tonight range from 10 to 15 kts with occasional
gusts around 20 kts, shift into the north and northwest at 15
to 25 kts with a few gusts approaching 30 kts into the afternoon
hours.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until noon CST Saturday for ILZ027>031-
036>038.
&&
$$
UPDATE...Smith
SHORT TERM...Barnes
LONG TERM...HJS
AVIATION...Smith
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
533 PM CST FRI NOV 20 2015
.SHORT TERM...(Tonight)
ISSUED AT 300 PM CST FRI NOV 20 2015
20z/2pm surface analysis continues to show a ridge of high pressure
extending from the Upper Midwest into the Ohio River Valley, while a
1010mb low gets organized over south-central Nebraska. Light snow
has developed in advance of the low as far east as central Iowa:
however, it is having a hard time spreading further eastward due to
a dry airmass in place beneath the ridge axis. Current surface
dewpoints across the KILX CWA are only in the teens and 20s, and
forecast soundings suggest the airmass will only slowly moisten from
the top-down as the day progresses. 19z run of the Rapid Refresh
model shows light precipitation arriving in the Illinois River
Valley between 6 and 9pm, then gradually spreading eastward to the
Indiana border toward dawn Saturday. If this solution pans out,
much of the Wabash River Valley will remain dry through the entire
night. Precipitation type will be a bit tricky, as surface
temperatures will initially be warm enough to support rain. However,
as evaporative cooling of the dry mid/low levels takes place, a
transition from rain to snow will occur from mid evening through the
overnight hours. Based on NAM/Rapid Refresh soundings, will include
a mix of rain/snow as far east as a Bloomington to Springfield line
by midnight...then further south/east to a Danville to Taylorville
line by dawn. The mixed precip will become all snow along/north of
a Rushville to Bloomington line overnight. Snowfall totals through
12z Saturday will range from around 1 inch along a Rushville to
Bloomington line...to 2 to 3 inches north of the Peoria area. Since
this will be the first snow of the upcoming winter season, decided
to add another row of counties to the Winter Weather Advisory to
include Fulton, Tazewell, and McLean.
.LONG TERM...(Saturday through Friday)
ISSUED AT 300 PM CST FRI NOV 20 2015
Complicated forecast continuing into tomorrow morning with the
winter storm continuing the snow fall roughly north of a line from
Rushville to Champaign...ending from west to east by noon. Areas in
central and southeastern Illinois will see a slow end to the rain as
well as colder air moves in behind the system. Whereas the bulk of
the snow will fall before 6 am, some additional accumulations will
fall through noon, particularly along and north of I-74 from
Galesburg to Bloomington/Normal. Winds will pick up out of the
northwest becoming somewhat breezy and dropping the temperatures
through the afternoon. Some blowing snow will be possible,
especially in open areas...but the majority of the snow will be
heavy and wet early on, and affected by partial melting.
Cold air moving into the region overnight with clearing skies, and
by Sunday morning, temperatures will drop into the single digits and
teens. Brisk winds in the morning will result in wind chills
dropping to -3C to 11C range. Sundays high temperatures will
struggle into the 30s, with areas in the north and nearer to any
remaining snow will have a hard time reaching the freezing mark. But
Sunday night the high pressure ridge axis will drift to the east and
southerly flow will kick back in, ushering warmer air into the
region and starting to slowly erode any remaining snow.
Southwesterly flow aloft assists the warm up with the next system
digging into the desert SW and amplifying the pattern across the
CONUS. Big question for the first part of the week will be how much
of the snow remains in the northern tier of the state. For now,
temperatures start on a warming trend that will continue through the
holiday. By Wednesday and Thursday, temps are above freezing through
the overnight as well and the next system lays out a boundary across
the region, providing a focus for plenty of rain in the Midwest in
time for holiday travel. So far the models are keeping rain
prolonged through Thanksgiving and into Friday. Cold air will move
in again behind the system, with chilly temperatures back for next
weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
ISSUED AT 525 PM CST FRI NOV 20 2015
Timing of precip into the forecast area and initial affects
on cigs the main challenge this evening, and then precip
type and changeover late tonight as a storm system shifts
south of the area. Rain has started over far western Il
and expect this light rain to gradually work its way
east this evening. However, forecast soundings continue
to show a very dry atmosphere in place in the low levels
so that will initially retard the eastward push to the
rain actually reaching the ground but will include at
least a VCSH across our west early this evening with the
main threat for rain and snow coming in later this evening
up in PIA and after midnight in BMI. RUC forecast soundings
continue to suggest the changeover to snow in PIA around
the midnight hour and between 08-10z at BMI with areas further
south seeing mostly rain until Saturday morning.
With the strongest lift moving across our area tomorrow morning
there looks to be a period of IFR cigs and vsbys in snow across
the north, with a changeover to light snow further south as our
easterly winds tonight range from 10 to 15 kts with occasional
gusts around 20 kts, shift into the north and northwest at 15
to 25 kts with a few gusts approaching 30 kts into the afternoon
hours.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory from 9 PM this evening to noon CST
Saturday for ILZ027>031-036>038.
&&
$$
SHORT TERM...Barnes
LONG TERM...HJS
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS GOODLAND KS
116 PM MST THU NOV 19 2015
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 206 AM MST THU NOV 19 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOWS LONG FETCH OF NW
FLOW EXTENDING FROM THE PACIFIC NW ACROSS THE CENTRAL ROCKIES INTO
THE THE PLAINS...WITH SARGE TROUGH ALONG THE MISSISSIPPI RIVER
VALLEY. AT THE SURFACE HIGH PRESSURE IS IN PLACE.
SNOW PACK CONTINUES TO BE A CONSIDERATION THROUGH AT LEAST THE SHORT
RANGE PERIODS FOR T/TD...AND ADJUSTMENTS WERE MADE ACCORDINGLY.
TODAY-TONIGHT...PASSING HIGH CLOUDS ASSOCIATED WITH WEAK RIPPLES
WITHIN NW FLOW ALOFT WILL CONTINUE THROUGH TONIGHT. OTHERWISE DRY
CONDITIONS WILL PERSIST. A COOLER AIR MASS WILL REMAIN IN PLACE
AND TEMPERATURES WILL BE AT LEAST 5-15F COOLER THAN YESTERDAY
ESPECIALLY IF WE SEE MORE EXTENSIVE/OPAQUE CLOUD COVER.
FRIDAY-FRIDAY NIGHT...A STRONGER SHORTWAVE TROUGH/CLIPPER EMBEDDED
WITH NW FLOW WILL MOVE THROUGH THE REGION ALONG WITH ANOTHER COLD
FRONT (PASSING LATE AFTERNOON). MOISTURE ADVECTION IS LIMITED DUE TO
THE TRAJECTORY/TRACK OF THIS SYSTEM...HOWEVER THERE WILL BE ENOUGH
FORCING TO SUPPORT A FEW RAIN/SNOW SHOWERS OR SPRINKLES/FLURRIES
DURING THESE PERIODS. MODELS SHOWS VERY STRONG GRADIENT
ALONG/BEHIND FRONT HIGHLIGHTED BY 8-10 MB 3HR PRESSURE RISES (10-15
MB 6 HR PRESSURE RISES). ITS HARD TO TELL HOW DEEP WE WILL MIX AS
THERE COULD BE EXTENSIVE CLOUD COVER AND POSSIBLE INVERSION ABOVE
LINGERING SNOW PACK. IF WE WERE TO MIX TO 850 MB WE COULD SEE WINDS
45-50 MPH. WINDS ABOVE THIS LAYER ARE EVEN HIGHER...SO THIS WILL
NEED TO BE WATCHED IN THE EVENT SHOWERS HELP MIXING AND CREATE
ISOLATED 60 MPH DOWNBURST. INCREASING WAA AHEAD OF THIS FRONT
SHOULD ALLOW SOME LOCATIONS TO WARM INTO THE MID 50S BEFORE
TEMPERATURES START DECREASING IN THE AFTERNOON.
SATURDAY-SATURDAY NIGHT...ANOTHER SHORTWAVE TROUGH IS ADVERTISED TO
PASS THROUGH THE NORTHERN PLAINS...HOWEVER THIS FEATURE IS NOT QUITE
AS STRONG...AND MOISTURE PROFILES ARE EVEN LESS FAVORABLE. DRY
CONDITIONS SHOULD BE EXPECTED THOUGH THESE PERIODS. THIS SHORTWAVE
WILL ALSO HELP REINFORCE THE COOLER POST FRONT AIR MASS...SO HIGHS
IN THE 30S ARE EXPECTED ACROSS OUR CWA AND I COULD SEE SOME
LOCATIONS WITH HIGHS AROUND 32.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 103 PM MST THU NOV 19 2015
SHORTWAVE TROUGH DROPPING OUT OF THE NORTHERN ROCKIES WILL BRING
SCATTERED FLURRIES/CHANCE OF LIGHT SNOW FRIDAY NIGHT. SNOW AMOUNTS
WILL BE LESS THAN A HALF INCH AND IMPACTS ARE EXPECTED TO BE
MINIMAL. SHORTWAVE RIDGING WILL BUILD IN ITS WAKE OVER THE WEEKEND
AND INTO NEXT WEEK WITH DRY CONDITIONS. TEMPERATURES ON SATURDAY
WILL BE MUCH BELOW NORMAL THEN WARM TO SLIGHTLY BELOW NORMAL ON
SUNDAY AND SLIGHTLY ABOVE NORMAL ON MONDAY. TEMPERATURES WILL BE A
BIT COOLER IN AREAS WITH DEEPEST SNOW COVER. ANOTHER FAST MOVING
SHORTWAVE TROUGH MOVES ACROSS IN THE ZONAL FLOW ON TUESDAY BUT
APPEARS TO LACK SUFFICIENT MOISTURE FOR PRECIPITATION SO WILL KEEP
IT DRY. RIDGING REBUILDS FOR THE REMAINDER OF THE LONG TERM PERIOD
AHEAD OF A SYSTEM CUTTING OFF IN THE GREAT BASIN. IT MIGHT BRING A
CHANCE FOR RAIN OR SNOW BY THURSDAY AS IT KICKS OUT ACROSS THE
CENTRAL AND NORTHERN ROCKIES...BUT AS OF NOW MODELS ONLY SHOWING
VERY LIGHT ACCUMULATIONS OF AN INCH OR TWO IF ANY AT ALL. THE
TRACK OF THE UPPER LOW APPEARS TO BE TOO FAR NORTH FOR SIGNIFICANT
ACCUMULATIONS IN THE CENTRAL PLAINS. IT DOES HOWEVER LOOK LIKE IT
WILL TAP INTO MUCH COLDER AIRMASS AROUND THURSDAY OR THURSDAY
NIGHT...SO COULD BE SOME HIGHLY CHANGEABLE WEATHER AROUND THE
HOLIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 905 AM MST THU NOV 19 2015
KGLD...VFR THROUGH THE PERIOD. CLOUDINESS WILL GRADUALLY INCREASE
THROUGH THE PERIOD AS A WEATHER SYSTEM MOVES TOWARD THE AREA.
SOUTHWEST WINDS JUST UNDER 12KTS AT TAF ISSUANCE EXPECTED TO BACK
TO THE SOUTH LATE IN THE AFTERNOON AS SFC HIGH MOVES EAST AND LOW
PRESSURE DEEPENS ALONG THE FRONT RANGE. LITTLE CHANGE EXPECTED
OVERNIGHT. FOR FRIDAY WINDS VEER TO THE WEST NEAR 10KTS BY
MID MORNING THEN WEST-NORTHWEST AT THE TAIL END OF THE TAF PERIOD
AS A COLD FRONT APPROACHES FROM THE NORTHWEST.
KMCK...VFR THROUGH THE PERIOD. CLOUDINESS WILL GRADUALLY INCREASE
LATE THIS AFTERNOON/EARLY EVENING WITH A MOSTLY CLOUDY/CLOUDY SKY
EXPECTED OVERNIGHT THROUGH FRIDAY. SOUTHWEST WINDS AROUND 6KTS AT
TAF ISSUANCE EXPECTED TO BACK TO THE SOUTH NEAR 5KTS BY 00Z. A
LIGHT SOUTH-SOUTHEAST WIND EXPECTED OVERNIGHT THROUGH MID MORNING
BEFORE VEERING TO THE WEST AROUND 6KTS AT THE END OF THE TAF
PERIOD AS A COLD FRONT APPROACHES.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
905 AM MST THU NOV 19 2015
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 206 AM MST THU NOV 19 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOWS LONG FETCH OF NW
FLOW EXTENDING FROM THE PACIFIC NW ACROSS THE CENTRAL ROCKIES INTO
THE THE PLAINS...WITH SARGE TROUGH ALONG THE MISSISSIPPI RIVER
VALLEY. AT THE SURFACE HIGH PRESSURE IS IN PLACE.
SNOW PACK CONTINUES TO BE A CONSIDERATION THROUGH AT LEAST THE SHORT
RANGE PERIODS FOR T/TD...AND ADJUSTMENTS WERE MADE ACCORDINGLY.
TODAY-TONIGHT...PASSING HIGH CLOUDS ASSOCIATED WITH WEAK RIPPLES
WITHIN NW FLOW ALOFT WILL CONTINUE THROUGH TONIGHT. OTHERWISE DRY
CONDITIONS WILL PERSIST. A COOLER AIR MASS WILL REMAIN IN PLACE
AND TEMPERATURES WILL BE AT LEAST 5-15F COOLER THAN YESTERDAY
ESPECIALLY IF WE SEE MORE EXTENSIVE/OPAQUE CLOUD COVER.
FRIDAY-FRIDAY NIGHT...A STRONGER SHORTWAVE TROUGH/CLIPPER EMBEDDED
WITH NW FLOW WILL MOVE THROUGH THE REGION ALONG WITH ANOTHER COLD
FRONT (PASSING LATE AFTERNOON). MOISTURE ADVECTION IS LIMITED DUE TO
THE TRAJECTORY/TRACK OF THIS SYSTEM...HOWEVER THERE WILL BE ENOUGH
FORCING TO SUPPORT A FEW RAIN/SNOW SHOWERS OR SPRINKLES/FLURRIES
DURING THESE PERIODS. MODELS SHOWS VERY STRONG GRADIENT
ALONG/BEHIND FRONT HIGHLIGHTED BY 8-10 MB 3HR PRESSURE RISES (10-15
MB 6 HR PRESSURE RISES). ITS HARD TO TELL HOW DEEP WE WILL MIX AS
THERE COULD BE EXTENSIVE CLOUD COVER AND POSSIBLE INVERSION ABOVE
LINGERING SNOW PACK. IF WE WERE TO MIX TO 850 MB WE COULD SEE WINDS
45-50 MPH. WINDS ABOVE THIS LAYER ARE EVEN HIGHER...SO THIS WILL
NEED TO BE WATCHED IN THE EVENT SHOWERS HELP MIXING AND CREATE
ISOLATED 60 MPH DOWNBURST. INCREASING WAA AHEAD OF THIS FRONT
SHOULD ALLOW SOME LOCATIONS TO WARM INTO THE MID 50S BEFORE
TEMPERATURES START DECREASING IN THE AFTERNOON.
SATURDAY-SATURDAY NIGHT...ANOTHER SHORTWAVE TROUGH IS ADVERTISED TO
PASS THROUGH THE NORTHERN PLAINS...HOWEVER THIS FEATURE IS NOT QUITE
AS STRONG...AND MOISTURE PROFILES ARE EVEN LESS FAVORABLE. DRY
CONDITIONS SHOULD BE EXPECTED THOUGH THESE PERIODS. THIS SHORTWAVE
WILL ALSO HELP REINFORCE THE COOLER POST FRONT AIR MASS...SO HIGHS
IN THE 30S ARE EXPECTED ACROSS OUR CWA AND I COULD SEE SOME
LOCATIONS WITH HIGHS AROUND 32.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 206 AM MST THU NOV 19 2015
NORTHWEST FLOW ALOFT REMAINS OVER THE REGION ON SUNDAY BEFORE AN
UPPER RIDGE OVER THE WESTERN CONUS FLATTENS OUT OVER THE HIGH PLAINS
ON MONDAY AND TUESDAY. THIS PATTERN WILL BRING DRY CONDITIONS AND
WARMER TEMPERATURES TO THE FORECAST THROUGH EARLY NEXT WEEK.
GUIDANCE IS SHOWING AN UPPER LOW MOVING OVER THE PACIFIC NORTHWEST
TUESDAY NIGHT. DRY CONDITIONS CONTINUE FOR THE AREA ON WEDNESDAY
AHEAD OF THIS SYSTEM AS IT TRAVELS EASTWARD TOWARDS THE PLAINS WITH
THE ASSOCIATED COLD FRONT LOOKING TO PASS THROUGH THE REGION BY
THURSDAY. COULD SEE PRECIP CHANCES LATER NEXT WEEK WITH THIS SYSTEM.
EXPECT TEMPERATURES TO WARM INTO EARLY NEXT WEEK WITH HIGHS IN THE
40S ON SUNDAY GRADUALLY INCREASING INTO THE 50S BY TUESDAY BEFORE
COOLING INTO THE UPPER 40S TO MID 50S FOR WEDNESDAY. CONTINUED TO
KEEP THE COOLER TEMPERATURES IN AREAS WHERE SNOWPACK MAY STILL BE
PRESENT. HOWEVER...SUSPECT MELTING WILL OCCUR BEFORE THE END OF THIS
PERIOD. LOWS WILL GENERALLY BE IN THE 20S. THE REGION COULD SEE A
BLAST OF COLD AIR TOWARDS THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 905 AM MST THU NOV 19 2015
KGLD...VFR THROUGH THE PERIOD. CLOUDINESS WILL GRADUALLY INCREASE
THROUGH THE PERIOD AS A WEATHER SYSTEM MOVES TOWARD THE AREA.
SOUTHWEST WINDS JUST UNDER 12KTS AT TAF ISSUANCE EXPECTED TO BACK
TO THE SOUTH LATE IN THE AFTERNOON AS SFC HIGH MOVES EAST AND LOW
PRESSURE DEEPENS ALONG THE FRONT RANGE. LITTLE CHANGE EXPECTED
OVERNIGHT. FOR FRIDAY WINDS VEER TO THE WEST NEAR 10KTS BY
MID MORNING THEN WEST-NORTHWEST AT THE TAIL END OF THE TAF PERIOD
AS A COLD FRONT APPROACHES FROM THE NORTHWEST.
KMCK...VFR THROUGH THE PERIOD. CLOUDINESS WILL GRADUALLY INCREASE
LATE THIS AFTERNOON/EARLY EVENING WITH A MOSTLY CLOUDY/CLOUDY SKY
EXPECTED OVERNIGHT THROUGH FRIDAY. SOUTHWEST WINDS AROUND 6KTS AT
TAF ISSUANCE EXPECTED TO BACK TO THE SOUTH NEAR 5KTS BY 00Z. A
LIGHT SOUTH-SOUTHEAST WIND EXPECTED OVERNIGHT THROUGH MID MORNING
BEFORE VEERING TO THE WEST AROUND 6KTS AT THE END OF THE TAF
PERIOD AS A COLD FRONT APPROACHES.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
418 AM MST THU NOV 19 2015
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 206 AM MST THU NOV 19 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOWS LONG FETCH OF NW
FLOW EXTENDING FROM THE PACIFIC NW ACROSS THE CENTRAL ROCKIES INTO
THE THE PLAINS...WITH SARGE TROUGH ALONG THE MISSISSIPPI RIVER
VALLEY. AT THE SURFACE HIGH PRESSURE IS IN PLACE.
SNOW PACK CONTINUES TO BE A CONSIDERATION THROUGH AT LEAST THE SHORT
RANGE PERIODS FOR T/TD...AND ADJUSTMENTS WERE MADE ACCORDINGLY.
TODAY-TONIGHT...PASSING HIGH CLOUDS ASSOCIATED WITH WEAK RIPPLES
WITHIN NW FLOW ALOFT WILL CONTINUE THROUGH TONIGHT. OTHERWISE DRY
CONDITIONS WILL PERSIST. A COOLER AIR MASS WILL REMAIN IN PLACE
AND TEMPERATURES WILL BE AT LEAST 5-15F COOLER THAN YESTERDAY
ESPECIALLY IF WE SEE MORE EXTENSIVE/OPAQUE CLOUD COVER.
FRIDAY-FRIDAY NIGHT...A STRONGER SHORTWAVE TROUGH/CLIPPER EMBEDDED
WITH NW FLOW WILL MOVE THROUGH THE REGION ALONG WITH ANOTHER COLD
FRONT (PASSING LATE AFTERNOON). MOISTURE ADVECTION IS LIMITED DUE TO
THE TRAJECTORY/TRACK OF THIS SYSTEM...HOWEVER THERE WILL BE ENOUGH
FORCING TO SUPPORT A FEW RAIN/SNOW SHOWERS OR SPRINKLES/FLURRIES
DURING THESE PERIODS. MODELS SHOWS VERY STRONG GRADIENT
ALONG/BEHIND FRONT HIGHLIGHTED BY 8-10 MB 3HR PRESSURE RISES (10-15
MB 6 HR PRESSURE RISES). ITS HARD TO TELL HOW DEEP WE WILL MIX AS
THERE COULD BE EXTENSIVE CLOUD COVER AND POSSIBLE INVERSION ABOVE
LINGERING SNOW PACK. IF WE WERE TO MIX TO 850 MB WE COULD SEE WINDS
45-50 MPH. WINDS ABOVE THIS LAYER ARE EVEN HIGHER...SO THIS WILL
NEED TO BE WATCHED IN THE EVENT SHOWERS HELP MIXING AND CREATE
ISOLATED 60 MPH DOWNBURST. INCREASING WAA AHEAD OF THIS FRONT
SHOULD ALLOW SOME LOCATIONS TO WARM INTO THE MID 50S BEFORE
TEMPERATURES START DECREASING IN THE AFTERNOON.
SATURDAY-SATURDAY NIGHT...ANOTHER SHORTWAVE TROUGH IS ADVERTISED TO
PASS THROUGH THE NORTHERN PLAINS...HOWEVER THIS FEATURE IS NOT QUITE
AS STRONG...AND MOISTURE PROFILES ARE EVEN LESS FAVORABLE. DRY
CONDITIONS SHOULD BE EXPECTED THOUGH THESE PERIODS. THIS SHORTWAVE
WILL ALSO HELP REINFORCE THE COOLER POST FRONT AIR MASS...SO HIGHS
IN THE 30S ARE EXPECTED ACROSS OUR CWA AND I COULD SEE SOME
LOCATIONS WITH HIGHS AROUND 32.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 206 AM MST THU NOV 19 2015
NORTHWEST FLOW ALOFT REMAINS OVER THE REGION ON SUNDAY BEFORE AN
UPPER RIDGE OVER THE WESTERN CONUS FLATTENS OUT OVER THE HIGH PLAINS
ON MONDAY AND TUESDAY. THIS PATTERN WILL BRING DRY CONDITIONS AND
WARMER TEMPERATURES TO THE FORECAST THROUGH EARLY NEXT WEEK.
GUIDANCE IS SHOWING AN UPPER LOW MOVING OVER THE PACIFIC NORTHWEST
TUESDAY NIGHT. DRY CONDITIONS CONTINUE FOR THE AREA ON WEDNESDAY
AHEAD OF THIS SYSTEM AS IT TRAVELS EASTWARD TOWARDS THE PLAINS WITH
THE ASSOCIATED COLD FRONT LOOKING TO PASS THROUGH THE REGION BY
THURSDAY. COULD SEE PRECIP CHANCES LATER NEXT WEEK WITH THIS SYSTEM.
EXPECT TEMPERATURES TO WARM INTO EARLY NEXT WEEK WITH HIGHS IN THE
40S ON SUNDAY GRADUALLY INCREASING INTO THE 50S BY TUESDAY BEFORE
COOLING INTO THE UPPER 40S TO MID 50S FOR WEDNESDAY. CONTINUED TO
KEEP THE COOLER TEMPERATURES IN AREAS WHERE SNOWPACK MAY STILL BE
PRESENT. HOWEVER...SUSPECT MELTING WILL OCCUR BEFORE THE END OF THIS
PERIOD. LOWS WILL GENERALLY BE IN THE 20S. THE REGION COULD SEE A
BLAST OF COLD AIR TOWARDS THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 417 AM MST THU NOV 19 2015
VFR CONDITIONS SHOULD CONTINUE THROUGH THE TAF PERIOD. 9-10 KFT
AGL CLOUD DECK OVERSPREADING THE REGION BY TONIGHT AS UPPER LEVEL
DISTURBANCE APPROACHES. SURFACE LOW BUILDING OVER EASTERN
COLORADO WILL CONTINUE TO MOVE EASTWARD AND WINDS WILL SHIFT FROM
THE W-SW TO THE SOUTH. PREVAILING WINDS WILL REMAIN LESS THAN
12KT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
207 AM MST THU NOV 19 2015
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 206 AM MST THU NOV 19 2015
EARLY MORNING WV IMAGERY AND RAP H5 ANALYSIS SHOWS LONG FETCH OF NW
FLOW EXTENDING FROM THE PACIFIC NW ACROSS THE CENTRAL ROCKIES INTO
THE THE PLAINS...WITH SARGE TROUGH ALONG THE MISSISSIPPI RIVER
VALLEY. AT THE SURFACE HIGH PRESSURE IS IN PLACE.
SNOW PACK CONTINUES TO BE A CONSIDERATION THROUGH AT LEAST THE SHORT
RANGE PERIODS FOR T/TD...AND ADJUSTMENTS WERE MADE ACCORDINGLY.
TODAY-TONIGHT...PASSING HIGH CLOUDS ASSOCIATED WITH WEAK RIPPLES
WITHIN NW FLOW ALOFT WILL CONTINUE THROUGH TONIGHT. OTHERWISE DRY
CONDITIONS WILL PERSIST. A COOLER AIR MASS WILL REMAIN IN PLACE
AND TEMPERATURES WILL BE AT LEAST 5-15F COOLER THAN YESTERDAY
ESPECIALLY IF WE SEE MORE EXTENSIVE/OPAQUE CLOUD COVER.
FRIDAY-FRIDAY NIGHT...A STRONGER SHORTWAVE TROUGH/CLIPPER EMBEDDED
WITH NW FLOW WILL MOVE THROUGH THE REGION ALONG WITH ANOTHER COLD
FRONT (PASSING LATE AFTERNOON). MOISTURE ADVECTION IS LIMITED DUE TO
THE TRAJECTORY/TRACK OF THIS SYSTEM...HOWEVER THERE WILL BE ENOUGH
FORCING TO SUPPORT A FEW RAIN/SNOW SHOWERS OR SPRINKLES/FLURRIES
DURING THESE PERIODS. MODELS SHOWS VERY STRONG GRADIENT
ALONG/BEHIND FRONT HIGHLIGHTED BY 8-10 MB 3HR PRESSURE RISES (10-15
MB 6 HR PRESSURE RISES). ITS HARD TO TELL HOW DEEP WE WILL MIX AS
THERE COULD BE EXTENSIVE CLOUD COVER AND POSSIBLE INVERSION ABOVE
LINGERING SNOW PACK. IF WE WERE TO MIX TO 850 MB WE COULD SEE WINDS
45-50 MPH. WINDS ABOVE THIS LAYER ARE EVEN HIGHER...SO THIS WILL
NEED TO BE WATCHED IN THE EVENT SHOWERS HELP MIXING AND CREATE
ISOLATED 60 MPH DOWNBURST. INCREASING WAA AHEAD OF THIS FRONT
SHOULD ALLOW SOME LOCATIONS TO WARM INTO THE MID 50S BEFORE
TEMPERATURES START DECREASING IN THE AFTERNOON.
SATURDAY-SATURDAY NIGHT...ANOTHER SHORTWAVE TROUGH IS ADVERTISED TO
PASS THROUGH THE NORTHERN PLAINS...HOWEVER THIS FEATURE IS NOT QUITE
AS STRONG...AND MOISTURE PROFILES ARE EVEN LESS FAVORABLE. DRY
CONDITIONS SHOULD BE EXPECTED THOUGH THESE PERIODS. THIS SHORTWAVE
WILL ALSO HELP REINFORCE THE COOLER POST FRONT AIR MASS...SO HIGHS
IN THE 30S ARE EXPECTED ACROSS OUR CWA AND I COULD SEE SOME
LOCATIONS WITH HIGHS AROUND 32.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 206 AM MST THU NOV 19 2015
NORTHWEST FLOW ALOFT REMAINS OVER THE REGION ON SUNDAY BEFORE AN
UPPER RIDGE OVER THE WESTERN CONUS FLATTENS OUT OVER THE HIGH PLAINS
ON MONDAY AND TUESDAY. THIS PATTERN WILL BRING DRY CONDITIONS AND
WARMER TEMPERATURES TO THE FORECAST THROUGH EARLY NEXT WEEK.
GUIDANCE IS SHOWING AN UPPER LOW MOVING OVER THE PACIFIC NORTHWEST
TUESDAY NIGHT. DRY CONDITIONS CONTINUE FOR THE AREA ON WEDNESDAY
AHEAD OF THIS SYSTEM AS IT TRAVELS EASTWARD TOWARDS THE PLAINS WITH
THE ASSOCIATED COLD FRONT LOOKING TO PASS THROUGH THE REGION BY
THURSDAY. COULD SEE PRECIP CHANCES LATER NEXT WEEK WITH THIS SYSTEM.
EXPECT TEMPERATURES TO WARM INTO EARLY NEXT WEEK WITH HIGHS IN THE
40S ON SUNDAY GRADUALLY INCREASING INTO THE 50S BY TUESDAY BEFORE
COOLING INTO THE UPPER 40S TO MID 50S FOR WEDNESDAY. CONTINUED TO
KEEP THE COOLER TEMPERATURES IN AREAS WHERE SNOWPACK MAY STILL BE
PRESENT. HOWEVER...SUSPECT MELTING WILL OCCUR BEFORE THE END OF THIS
PERIOD. LOWS WILL GENERALLY BE IN THE 20S. THE REGION COULD SEE A
BLAST OF COLD AIR TOWARDS THE END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1028 PM MST WED NOV 18 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. WEST TO NORTHWEST
WINDS OF 5 TO NEAR 10 KNOTS SLOWLY SHIFT TO THE SOUTH THROUGH THE
PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
104 PM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER SOUTHEAST CANADA WILL SLIDE EAST TODAY AS A
COLD FRONT APPROACHES FROM THE WEST. THE FRONT CROSSES THE AREA
THIS EVENING...WITH HIGH PRESSURE BUILDING IN FRIDAY AND
SATURDAY. A DRY COLD FRONT WILL MOVE ACROSS THE REGION SATURDAY
NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST GOES WATER VAPOR IMAGERY DEPICTS MOISTURE PLUME LIFTING ALONG
THE SE COASTAL PLAIN INTO THE LOCAL AREA DOWNSTREAM OF A POTENT NRN
STREAM CLOSED LOW OVER SOUTH CENTRAL CANADA. AT THE SFC...COLD FRONT
HAS LOCATED OVER THE CENTRAL APPALACHIANS WITH A WARM FRONT OVER NC.
SHOWER COVERAGE HAS DIMINISHED THIS MORNING...WITH THE BEST COVERAGE
OVER SOUTHERN VA AND NE NC. ELSEWHERE...SHOWERS HAVE BECOME MORE
SCATTERED IN NATURE. FEW LIGHTNING STRIKES WERE OBSERVED OVER
MECKLENBURG COUNTY WHERE RAP GUIDANCE INDICATES SLIGHTLY STEEPER MID
LEVEL LAPSE RATES TO GO ALONG WITH <250 J/KG MUCAPE...BUT HAS SINCE
DIMINISHED. DO NOT ANTICIPATE MORE THAN ISOLATED/EMBEDDED RUMBLE OF
THUNDER BASED ON VERY LITTLE INSTABILITY...BUT WILL MAINTAIN SLIGHT
CHANCE THUNDER WORDING IN FORECAST.
FOR THE REST OF THE DAY...SHORTWAVE ENERGY PUSHES OFFSHORE AS THE
COLD FRONT SLOWLY CROSSES THE REGION. SWLY FLOW ALOFT WILL
PERSIST...BUT BEST MOISTURE PUSHES EAST OF INTERSTATE 95 BY EARLY
AFTERNOON LEAVING ONLY SCATTERED SHOWERS OVER THE PIEDMONT INTO
CENTRAL VA. ISENTROPIC LIFT INDICATED IN NAM12 THETA SURFACES WILL
LIKELY RESULT IN INCREASING COVERAGE ALONG THE COAST AS THE SHOWERS
FROM NC LIFT INTO THE ERN AREA. WILL MAINTAIN LIKELY TO CATEGORICAL
POPS EAST OF INTERSTATE 95. ADDITIONAL QPF AMOUNTS WILL RANGE FROM A
LESS THAN QUARTER OF AN INCH WEST TO HALF AN INCH EAST. HIGHEST
AMOUNTS IN THE SOUTHEAST WHERE AREAS COULD SEE UP TO AN INCH. HIGHS
GENERALLY IN THE UPPER 60S TO LOW 70S. WILL BEGIN TO SEE BREAKS IN
THE CLOUDS LATE TODAY OVER THE PIEDMONT...PERHAPS INTO CENTRAL VA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
COLD FRONT PROGGED INVOF CHES BAY BY 00Z FRI THEN QUICKLY MOVES
OFFSHORE BY 06Z. THUS...SLGT CHANCE-CHANCE EVENING POPS WILL BE
MAINTAINED MAINLY EAST OF I-95 TO CHES BAY...WITH LIKELY POPS
NEAR THE COAST. ENOUGH MOISTURE NOTED TO KEEP SLIGHT CHANCE POPS
NEAR THE COAST AFTER MIDNIGHT. OTHERWISE...TSCTNS SHOW COLUMN
DRYING WHICH SHOULD RESULT IN DECREASING CLOUDINESS WEST OF THE
BAY. CAA SETS IN AS WINDS SHIFT TO THE NW. LOWS DROP BACK INTO THE
40S WRN HALF OF FA...50-55 ALONG THE COAST.
HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST FRI INTO SAT.
STRONG SUBSIDENCE RESULTS IN MAINLY CLEAR SKIES ALONG WITH A RETURN
TO NEAR NORMAL TEMPS. RATHER BREEZY FRI...ESPECIALLY ALONG THE
COAST. HIGHS FRI UPPER 50S TO LOWER 60S. LOWS FRI NIGHT LOWER 30S
NW TO LOWER 40S SERN COASTAL AREAS. HIGHS SAT IN THE MID-UPPER
50S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
OVERALL HAVE GOOD MODEL AGREEMENT FROM SUNDAY THROUGH
NEXT WEDNESDAY AS ONE COLD FRONT SWEEPS ACROSS THE MID ATLANTIC
REGION LATE SATURDAY NIGHT AND THEN HIGH PRESSURE MOVES INTO THE
AREA AND LINGERS THROUGH MID WEEK. THE 12Z GFS WAS MORE AGGRESSIVE
PUSHING THE FRONT OFF THE COAST AND ALSO IS A LITTLE COLDER WITH
850 TEMPS FALLING TO AROUND -10C AROUND 06Z MONDAY BEFORE THE AIR
MASS MODIFIES. THE 12Z ECMWF SLOWS THE PUSH OF THE COLDER AIR AND
ACTUALLY KEEPS IT FURTHER TO THE NORTH AND ALLOWS FOR MORE NELY
FLOW. IN SPITE OF THESE DIFFERENCES...THE FORECAST GENERALLY SHOWS
DRY AND COOL WEATHER FROM SUNDAY INTO WEDNESDAY. THE COLD FRONT IS
EXPECTED TO GO THROUGH DRY AS THE INITIAL BOUNDARY THAT GOES
THROUGH ON THURSDAY SUPPRESSES THE GULF MOISTURE AND WITH THE
WEST TO EAST MOVEMENT OF THE FRONT...ANY MOISTURE SHOULD BE RUNG
OUT AS THE BOUNDARY CROSSES THE MOUNTAINS. EXPECT A COLDER AND
WINDIER DAY ON SUNDAY AS THE TIGHTENING PRESSURE GRADIENT AND COLD
AIR ALOFT ALLOW FOR GOOD MIXING. AFTER A COLD NIGHT SUNDAY
NIGHT (WHICH COULD SEE WIDESPREAD FREEZING TEMPS)...EXPECT TO SEE
A GRADUAL WARMING TREND AS THE SFC HIGH SLOWLY MOVES OFF TO THE
EAST AND THE COLD AIR RETREATS BACK NORTH.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
COLD FRONT STILL WEST OF THE MTS WITH A WARM FRNT MOVG NORTH
ACROSS NC AT 18Z. STILL PLNTY OF MSTR AHEAD OF THE CDFRNT AND
MODELS CONT TO SHOW AREAS OF RAIN MOVG ACROSS THE RGN FOR THE
NEXT 6-9 HRS. HIGH RES DATA SUGGESTS A LINE OF CONVECTION MAY TRY
TO DVLP TOWARDS SUNSET MAINLY EAST OF I95 THEN MOVE EAST MOVG OFF
THE COAST BY 03Z. THUS...CONTINUED THE IFR/MVFR CIGS WITH TEMPO
GROUP FOR IFR VSBYS IN RAIN NEXT SVRL HRS. BEST TIMING FOR ANY
THUNDER ACROSS SERN TAF SITES WILL BE AFTR 21Z...BUT CONFIDENCE
NOT HIGH ENUF TO INCLUDE THUNDER IN THE TAFS. MAY END UP BEING
SHWRS WITH LCLLY HVY RAINFALL AS INSTABILITY LOOKS MARGINAL AT
BEST.
CDFRNT EXITS OFF THE COAST LATE THIS EVENING WITH TSCTNS SHOWING
RAPID COLUMN DRYING. THUS EXPECT A RATHER QUICK JUMP INTO VFR CIGS
THEN CLEARING AFTR 06Z. GUSTY S-SE WINDS BTWN 15-25 KTS THIS AFTRN
ALONG THE COAST WILL ACTUALLY DMNSH THIS EVENING BEFORE SHIFTING
TO THE NNW LATE TONIGHT THEN BECOME GUSTY ONCE AGAIN. DATA SUPPORTS
GUSTS BTWN 25-30 KTS FRI MORNING ACROSS SERN TAF SITES.
OUTLOOK...ANOTHER FRONT BRINGS STRONGER N-NW WINDS INTO SUN ALTHOUGH
IT LOOKS TO STAY DRY.
&&
.MARINE...
GIVEN THE RAPID INCREASE IN S-SE WINDS ACROSS THE LWR CHES BAY
PAST FEW HRS...WENT AHEAD AND STARTED THE SCA HEADLINE FOR THE LWR
JAMES RIVER WITH THE 1 PM UPDATE. STILL EXPECT A LULL IN THE WINDS
THIS EVENING BEFORE THE CAA SETS IN LATER TONITE.
PVS DSCN:
SE WNDS STEADILY INCRSG ATTM...STILL MNLY BLO SCA BUT W/ CDFNT
APPROACHING FM W AND PRES GRADIENT TIGHTEN UP A BIT MORE...CONTD
STRENGTHENING XPCD. THE PERSISTENT ESE FLO OVR THE WRN ATLC HAS
KICKED SEAS UP TO 5 TO 7 FT IN THE CSTL WTRS AND 3 TO 4 FT IN THE
LWR BAY. GUSTY SE WNDS CONT INTO THIS AFTN...THEN THE CDFNT
CROSSES THE WTRS THIS EVE W/ A BRIEF 4 TO 8 HR WEAKENING OF THE
WINDS BEFORE THE COLDER AIR ALOFT HITS THE WTRS AFT 06Z/20 W/ A
NNW SURGE OF 20 TO 30 KT (MAYBE BRIEF GALE GUSTS...ESP ON THE OCN
CENTERED ON 12Z/20). XPCG THIS SURGE TO LINGER INTO FRIDAY
AFTERNOON BEFORE WEAKENING AS SFC HI BUILDS INTO THE RGN FM THE W.
FOR THE WEEKEND...SHOULD SEE BENIGN CONDITIONS ON SATURDAY AS HIGH
PRESSURE IS IN PLACE AND THE WIND WEAKENS TO 5 TO 10 KT...EXPECT
THE SEAS TO GRADUALLY DIMINISH AS WELL. THE FLOW WILL TURN SW ON
SATURDAY NIGHT AS ANOTHER COLD FRONT SWEEPS THROUGH THE AREA. THE
MODELS SHOW ANOTHER STRONG SURGE OF COLD AIR BEHIND THIS FRONT SO
EXPECT THE WIND AND SEAS TO PICK UP ONCE AGAIN WITH SCA EXPECTED.
BY EARLY NEXT WEEK...HIGH PRESSURE ONCE AGAIN BUILDS OVER THE
WATERS AND CONDITIONS SHOULD IMPROVE ONCE AGAIN.
&&
.TIDES/COASTAL FLOODING...
LEVELS ACROSS THE LWR MD ERN SHORE TOPPED OUT BLO MINOR FLOODING
THRESHOLDS THIS MORNING AS IT APPEARS WINDS WERE TO LIGHT. GIVEN
THE INCREASE IN WINDS THIS AFTRN AND EVENING...WATER LEVELS ARE
EXPECTED TO COME CLOSE TO MINOR FLOODING THRESHOLDS ALONG THE BAY
SIDE OF THE LOWER MD ERN SHORE AS WELL AS TIDAL POTOMAC LOCATIONS
OF THE NORTHERN NECK CONCURRENT WITH TONIGHTS HIGH TIDE CYCLES.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO NOON EST FRIDAY FOR
ANZ635>637.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL NOON EST FRIDAY FOR ANZ638.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ650-652-
654-656-658.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MAS/SAM
SHORT TERM...MAS/MPR
LONG TERM...ESS
AVIATION...MPR
MARINE...MPR
TIDES/COASTAL FLOODING...MPR
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1017 AM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER SOUTHEAST CANADA WILL SLIDE EAST TODAY AS A
COLD FRONT APPROACHES FROM THE WEST. THE FRONT CROSSES THE AREA
THIS EVENING...WITH HIGH PRESSURE BUILDING IN FRIDAY AND
SATURDAY. A DRY COLD FRONT WILL MOVE ACROSS THE REGION SATURDAY
NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST GOES WATER VAPOR IMAGERY DEPICTS MOISTURE PLUME LIFTING ALONG
THE SE COASTAL PLAIN INTO THE LOCAL AREA DOWNSTREAM OF A POTENT NRN
STREAM CLOSED LOW OVER SOUTH CENTRAL CANADA. AT THE SFC...COLD FRONT
HAS LOCATED OVER THE CENTRAL APPALACHIANS WITH A WARM FRONT OVER NC.
SHOWER COVERAGE HAS DIMINISHED THIS MORNING...WITH THE BEST COVERAGE
OVER SOUTHERN VA AND NE NC. ELSEWHERE...SHOWERS HAVE BECOME MORE
SCATTERED IN NATURE. FEW LIGHTNING STRIKES WERE OBSERVED OVER
MECKLENBURG COUNTY WHERE RAP GUIDANCE INDICATES SLIGHTLY STEEPER MID
LEVEL LAPSE RATES TO GO ALONG WITH <250 J/KG MUCAPE...BUT HAS SINCE
DIMINISHED. DO NOT ANTICIPATE MORE THAN ISOLATED/EMBEDDED RUMBLE OF
THUNDER BASED ON VERY LITTLE INSTABILITY...BUT WILL MAINTAIN SLIGHT
CHANCE THUNDER WORDING IN FORECAST.
FOR THE REST OF THE DAY...SHORTWAVE ENERGY PUSHES OFFSHORE AS THE
COLD FRONT SLOWLY CROSSES THE REGION. SWLY FLOW ALOFT WILL
PERSIST...BUT BEST MOISTURE PUSHES EAST OF INTERSTATE 95 BY EARLY
AFTERNOON LEAVING ONLY SCATTERED SHOWERS OVER THE PIEDMONT INTO
CENTRAL VA. ISENTROPIC LIFT INDICATED IN NAM12 THETA SURFACES WILL
LIKELY RESULT IN INCREASING COVERAGE ALONG THE COAST AS THE SHOWERS
FROM NC LIFT INTO THE ERN AREA. WILL MAINTAIN LIKELY TO CATEGORICAL
POPS EAST OF INTERSTATE 95. ADDITIONAL QPF AMOUNTS WILL RANGE FROM A
LESS THAN QUARTER OF AN INCH WEST TO HALF AN INCH EAST. HIGHEST
AMOUNTS IN THE SOUTHEAST WHERE AREAS COULD SEE UP TO AN INCH. HIGHS
GENERALLY IN THE UPPER 60S TO LOW 70S. WILL BEGIN TO SEE BREAKS IN
THE CLOUDS LATE TODAY OVER THE PIEDMONT...PERHAPS INTO CENTRAL VA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
COLD FRONT PROGGED INVOF CHES BAY BY 00Z FRI THEN QUICKLY MOVES
OFFSHORE BY 06Z. THUS...SLGT CHANCE-CHANCE EVENING POPS WILL BE
MAINTAINED MAINLY EAST OF I-95 TO CHES BAY...WITH LIKELY POPS
NEAR THE COAST. ENOUGH MOISTURE NOTED TO KEEP SLIGHT CHANCE POPS
NEAR THE COAST AFTER MIDNIGHT. OTHERWISE...TSCTNS SHOW COLUMN
DRYING WHICH SHOULD RESULT IN DECREASING CLOUDINESS WEST OF THE
BAY. CAA SETS IN AS WINDS SHIFT TO THE NW. LOWS DROP BACK INTO THE
40S WRN HALF OF FA...50-55 ALONG THE COAST.
HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST FRI INTO SAT.
STRONG SUBSIDENCE RESULTS IN MAINLY CLEAR SKIES ALONG WITH A RETURN
TO NEAR NORMAL TEMPS. RATHER BREEZY FRI...ESPECIALLY ALONG THE
COAST. HIGHS FRI UPPER 50S TO LOWER 60S. LOWS FRI NIGHT LOWER 30S
NW TO LOWER 40S SERN COASTAL AREAS. HIGHS SAT IN THE MID-UPPER
50S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
OVERALL HAVE GOOD MODEL AGREEMENT FROM SUNDAY THROUGH
NEXT WEDNESDAY AS ONE COLD FRONT SWEEPS ACROSS THE MID ATLANTIC
REGION LATE SATURDAY NIGHT AND THEN HIGH PRESSURE MOVES INTO THE
AREA AND LINGERS THROUGH MID WEEK. THE 12Z GFS WAS MORE AGGRESSIVE
PUSHING THE FRONT OFF THE COAST AND ALSO IS A LITTLE COLDER WITH
850 TEMPS FALLING TO AROUND -10C AROUND 06Z MONDAY BEFORE THE AIR
MASS MODIFIES. THE 12Z ECMWF SLOWS THE PUSH OF THE COLDER AIR AND
ACTUALLY KEEPS IT FURTHER TO THE NORTH AND ALLOWS FOR MORE NELY
FLOW. IN SPITE OF THESE DIFFERENCES...THE FORECAST GENERALLY SHOWS
DRY AND COOL WEATHER FROM SUNDAY INTO WEDNESDAY. THE COLD FRONT IS
EXPECTED TO GO THROUGH DRY AS THE INITIAL BOUNDARY THAT GOES
THROUGH ON THURSDAY SUPPRESSES THE GULF MOISTURE AND WITH THE
WEST TO EAST MOVEMENT OF THE FRONT...ANY MOISTURE SHOULD BE RUNG
OUT AS THE BOUNDARY CROSSES THE MOUNTAINS. EXPECT A COLDER AND
WINDIER DAY ON SUNDAY AS THE TIGHTENING PRESSURE GRADIENT AND COLD
AIR ALOFT ALLOW FOR GOOD MIXING. AFTER A COLD NIGHT SUNDAY
NIGHT (WHICH COULD SEE WIDESPREAD FREEZING TEMPS)...EXPECT TO SEE
A GRADUAL WARMING TREND AS THE SFC HIGH SLOWLY MOVES OFF TO THE
EAST AND THE COLD AIR RETREATS BACK NORTH.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
AREA OF RA PROGRESSING TO THE CST ATTM. PDS OF MNLY MVFR
CIGS/VSBYS W/ THIS RA. ADDITIONAL SHRAS BACK TO THE WSW BEHIND
THIS AREA. WILL HAVE IFR/LO END MVFR CONDS AFT THIS BAND OF RA
EXITS THE CST INTO THE AFTN (EVE TWD THE CST). VERY LO PROB FOR
THUNDER (PRIMARILY NR THE CST) LATE MRNG INTO MID AFTN. SE TO S
WNDS TO BECOME GUSTY TO 20-30 KT BEFORE BECOMING SW THIS EVE.
CDFNT PUSHES OFF THE CST TNGT. HI PRES THEN BUILDS IN FM THE W
FRI. THIS WILL RESULT IN DRY CONDS WITH A GUSTY N
WIND...DIMINISHING FRI AFTN. LIGHT WINDS FRI NIGHT INTO MID DAY
SAT. ANOTHER FRONT BRINGS STRONGER N-NW WINDS INTO SUN ALTHOUGH IT
LOOKS TO STAY DRY.
&&
.MARINE...
SE WNDS STEADILY INCRSG ATTM...STILL MNLY BLO SCA BUT W/ CDFNT
APPROACHING FM W AND PRES GRADIENT TIGHTEN UP A BIT MORE...CONTD
STRENGTHENING XPCD. THE PERSISTENT ESE FLO OVR THE WRN ATLC HAS
KICKED SEAS UP TO 5 TO 7 FT IN THE CSTL WTRS AND 3 TO 4 FT IN THE
LWR BAY. GUSTY SE WNDS CONT INTO THIS AFTN...THEN THE CDFNT
CROSSES THE WTRS THIS EVE W/ A BRIEF 4 TO 8 HR WEAKENING OF THE
WINDS BEFORE THE COLDER AIR ALOFT HITS THE WTRS AFT 06Z/20 W/ A
NNW SURGE OF 20 TO 30 KT (MAYBE BRIEF GALE GUSTS...ESP ON THE OCN
CENTERED ON 12Z/20). XPCG THIS SURGE TO LINGER INTO FRIDAY
AFTERNOON BEFORE WEAKENING AS SFC HI BUILDS INTO THE RGN FM THE W.
FOR THE WEEKEND...SHOULD SEE BENIGN CONDITIONS ON SATURDAY AS HIGH
PRESSURE IS IN PLACE AND THE WIND WEAKENS TO 5 TO 10 KT...EXPECT
THE SEAS TO GRADUALLY DIMINISH AS WELL. THE FLOW WILL TURN SW ON
SATURDAY NIGHT AS ANOTHER COLD FRONT SWEEPS THROUGH THE AREA. THE
MODELS SHOW ANOTHER STRONG SURGE OF COLD AIR BEHIND THIS FRONT SO
EXPECT THE WIND AND SEAS TO PICK UP ONCE AGAIN WITH SCA EXPECTED.
BY EARLY NEXT WEEK...HIGH PRESSURE ONCE AGAIN BUILDS OVER THE
WATERS AND CONDITIONS SHOULD IMPROVE ONCE AGAIN.
&&
.TIDES/COASTAL FLOODING...
A COLD FRONT APPROACHES FM THE W THROUGH MIDDAY...AND SLOLY
PUSHES OFFSHORE THIS EVE. POSITIVE TIDAL ANOMALIES STILL ON TRACK
TO BE 1 TO 1.5 FT OVER THE MIDDLE BAY (ESP ON THE LWR MD ERN
SHORE). WATER LEVELS ARE EXPECTED TO COME CLOSE TO MINOR FLOODING
THRESHOLDS ALONG THE BAY SIDE OF THE LOWER MD ERN SHORE AS WELL AS
TIDAL POTOMAC LOCATIONS OF THE NORTHERN NECK CONCURRENT WITH HIGH
TIDE CYCLES INTO TNGT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO NOON EST FRIDAY FOR
ANZ635>638.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ630>634.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ650-652-
654-656-658.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MAS/SAM
SHORT TERM...MAS/MPR
LONG TERM...ESS
AVIATION...ALB/LKB/DAP
MARINE...ALB/ESS
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1201 AM EST THU NOV 19 2015
.UPDATE...
ISSUED AT 1000 PM EST WED NOV 18 2015
BAND OF RAIN SHOWERS HAS COMPLETELY MOVED OUT OF THE AREA AND THE
FORECAST HAS BEEN UPDATED ACCORDINGLY. WIND STILL GUSTING 20 TO 30
MPH OUT OF THE SSW. NEXT BATCH OF RAIN SHOWERS ARRIVES LATE
TONIGHT...BUT MAINLY INTO TOMORROW MORNING ASSOCIATED WITH NEXT
SHORTWAVE AND SFC TROUGH/COLD FRONT AND DEEPER MOISTURE. LOW LEVEL
TEMPERATURES WILL STILL NOT BE COLD ENOUGH FOR ANY SNOW (H8 TEMPS
-1C TO +1C). THE COLDER AIR PLOWS THROUGH THE REGION VIA
INCREASING VERY GUSTY SW/WSW WINDS THROUGH LATTER MORNING AND
AFTERNOON...FOR WHICH WE WILL START TO SEE CHANGEOVERS TO SNOW
WITH LITTLE TO NO ACCUMULATION. GUSTS IN THE AFTERNOON 35-45 MPH
IN MANY LOCALES...HIGHEST IMMEDIATELY DOWNWIND OF LAKE MICHIGAN
(NW LOWER COAST AND MACKINAC COUNTY OF EASTERN UPPER).
&&
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 323 PM EST WED NOV 18 2015
OCCLUDED SURFACE LOW CENTER HAS REACHED NRN MINNESOTA LATE THIS
AFTERNOON...WITH THE ASSOCIATED COLD FRONT EXTENDING SOUTHWARD THRU
CENTRAL WISCONSIN AND CENTRAL ILLINOIS INTO THE LOWER MISSISSIPPI
VALLEY. WARM/MOIST AIR CONTINUES TO STREAM NORTHWARD OUT OF THE GULF
ALONG AND AHEAD OF THE COLD FRONT...AND INTO MICHIGAN. SFC DWPTS ARE
NOW MAINLY IN THE UPPER 40S ACROSS OUR ENTIRE CWA... WITH ALL LOCAL
OBS REPORTING AT LEAST A PERIOD OF RAIN DURING THE AFTERNOON.
NEXT WAVE OF WIDESPREAD RAIN IS MOVING THRU SRN LWR MICHIGAN TOWARD
OUR CWA...TARGETING THE ERN HALF FOR HIGHEST POPS FOR THE REST OF
THE AFTERNOON INTO THIS EVENING. NAM12...RAP13 AND HRRR ALL SUGGEST
THIS SCENARIO WITH SLIGHT VARIATIONS...AND OVERALL MODEL TRENDS HAVE
BEEN DOWNWARD FOR EXPECTED POPS LATE THIS AFTERNOON THRU TONIGHT. IN
FACT...ALL OF THE ABOVE MODELS NEARLY DISSIPATE THE AREA OF SHOWERS
CURRENTLY DEVELOPING OVER WISCONSIN BEFORE IT CAN REACH MICHIGAN
TONIGHT...HOLDING OFF ON THE REDEVELOPMENT OF BETTER POPS UNTIL
AFTER 12Z THURSDAY. HAVE DIMINISHED POPS FOR TONIGHT...BUT STILL
TARGET ERN SECTIONS OF OUR CWA FOR BEST CHANCE OF RAIN. LOW LEVELS
DO BEGIN TO COOL IN THE WAKE OF THE COLD FRONT TONIGHT...BUT
SUFFICIENTLY COLD AIR TO RESULT IN MIXED PRECIP AND/OR SNOW WILL
HOLD OFF UNTIL TOMORROW. THUS...ALL PRECIP WILL REMAIN LIQUID THRU
THE NIGHT...WITH OVERNIGHT LOWS FALLING INTO THE LOWER 40S.
STRONGEST CORRIDOR OF LOW LEVEL WINDS HAS REACHED OUR CWA...AND SO
FAR HAVE REMAINED JUST BELOW WIND ADVISORY CRITERIA. HAVE SEEN
NOTHING UPSTREAM OVER WISCONSIN TO INDICATE ANY FURTHER
STRENGTHENING OF WIND SPEEDS...AND WE MAY EVEN SEE A SLIGHT DIMINISH
LATER THIS EVENING AND OVERNIGHT. SO...AT THIS POINT...NO WIND
ADVISORY WILL BE NEEDED...BUT WILL CONTINUE TO KEEP A CLOSE EYE ON
LOCAL SURFACE OBS.
&&
.SHORT TERM...(THURSDAY THROUGH SATURDAY)
ISSUED AT 323 PM EST WED NOV 18 2015
HIGH IMPACT WEATHER POTENTIAL: LINGERING WIND CONCERNS THURSDAY.
ADDRESSING POTENTIAL WIDESPREAD SNOW EVENT SATURDAY.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: DEEP TROUGH DIGGING THROUGH
THE CENTRAL PART OF THE COUNTRY...LED IN CHARGE BY OPENING SOUTHERN
STREAM WAVE PIVOTING ACROSS WISCONSIN. FAR UPSTREAM PACIFIC FLOW
REGIME A TOUCH MORE "FLATISH" IN APPEARANCE...WITH ROBUST UPPER JET
CORE PUNCHING THROUGH THE NORTHWEST STATES. PATTERN SET TO GO
THROUGH SOME CHANGES IN THE COMING DAYS...WITH STRONG SECONDARY JET
MAX ACROSS THE NORTH PACIFIC FORCING AMPLIFYING AND TRANSIENT
RIDGING ACROSS THE NORTHEAST PACIFIC. SUBTLE WAVE DIVING DOWN THE
FRONT SIDE OF THIS RIDGE AMPLIFICATION...ALONG WITH THE POTENTIAL
STRENGTHENING OF UPPER JET CORE ALONG RIDGE/TROUGH INTERFACE...COULD
WORK IN TANDEM TO DRUM UP A RATHER SIGNIFICANT SNOW EVENT FOR AT
LEAST SOME ACROSS THE GREAT LAKES HEADING INTO THIS WEEKEND.
OTHERWISE...A MUCH MORE NOVEMBER FEEL EXPECTED THURSDAY INTO THE
WEEKEND...AS TROUGHING AND MODIFIED POLAR AIR DOMINATES.
PRIMARY FORECAST CONCERNS/CHALLENGES: INITIAL CONCERNS CENTERED ON
WIND GUSTS AND LAKE INDUCED SNOW SHOWER POTENTIAL THURSDAY AND
FRIDAY. ATTENTION DIRECTED TO POSSIBLE WINTER STORM IMPACTS HEADING
INTO AND THROUGH SATURDAY.
DETAILS: MAIN SYSTEM CONTINUES TO LIFT WELL NORTH OF THE AREA
TONIGHT AND THURSDAY...DRAGGING MAIN COLD FRONT ACROSS NORTHERN
MICHIGAN THURSDAY MORNING. ATTENDANT CAA AND REMNANT TIGHT PRESSURE
GRADIENT WILL WORK IN TANDEM TO CONTINUE THE GUSTY WINDS...ALTHOUGH
WIND DIRECTION WILL TURN DECIDEDLY MORE SOUTHWEST AFTER FRONTAL
PASSAGE. WINDS LOOK TO BE SUSTAINED AT 15 TO 25 MPH...WITH BUFKIT
MOMENTUM TRANSFER EASILY SUPPORTING WIDESPREAD WIND GUSTS A GOOD 10
OR SO MILES PER HOUR STRONGER...WITH GUSTS PUSHING 40 MPH AT TIMES
ALONG THE EXPOSED LAKE MICHIGAN COAST. BAND OF RAIN/SNOW SHOWERS TO
ACCOMPANY PASSING COLD FRONT...WITH PRECIP COVERAGE NO DOUBT
AUGMENTED BY INCREASING LAKE PROCESSES. COLD AIR WILL ONLY DEEPENING
WITH TIME...WITH AMPLE AIR/WATER TEMPERATURE DIFFERENCE TO CONTINUE
LAKE INDUCED SNOW SHOWERS IN FAVORED WSW-SW FLOW AREAS (TIP OF THE
MITT AND STRAITS). DEEPEST MOISTURE AND BEST SYNOPTIC FORCING
CONTINUES TO REMAIN NORTH OF OUR AREA...AND SAID WIND DIRECTION
MEANS NO MULTI-LAKE CONNECTION. SOUNDINGS SHOW DOWN LOW INVERTED-V
SIGNATURE...INDICATIVE OF UPSTREAM LOWER LEVEL DRY AIR AND NO LAKE
SUPERIOR PRECONDITIONING. SO...DESPITE MORE THAN FAVORABLE DELTA T/S
IN THE HIGH TEENS...JUST NOT SEEING A WHOLE LOT OF POTENTIAL FOR ANY
SIGNIFICANT SNOW ACCUMULATION (NOT MUCH MORE THAN AN INCH).
ABOVE TRENDS CONTINUE THURSDAY NIGHT AND FRIDAY...ALTHOUGH WINDS
GRADUALLY WEAKEN AND SLOWLY VEER WITH TIME. LIMITED MOISTURE
CONTINUES...WITH NO MULTI-LAKE CONNECTION EVER ESTABLISHED.
SO...MOSTLY LIGHT LAKE SNOWS WILL CONTINUE...FOCUSED ACROSS THE TIP
OF THE MITT WHERE ANOTHER INCH OR SO IS EXPECTED BY LATER FRIDAY.
MUCH...MUCH COLDER BY FRIDAY...ALTHOUGH HIGHS IN THE MID 30S/AROUND
40 ABOUT ON PAR FOR THIS TIME OF YEAR.
ATTENTION FRIDAY NIGHT AND SATURDAY DIRECTED AT THAT POTENTIAL SNOW
PRODUCING SYSTEM TALKED ABOUT IN THE OPENING PARAGRAPH. WOULD LOVE
TO OFFER MORE CONCRETE ANSWERS...BUT THERE IS SIMPLY TOO MUCH
UNCERTAINTY TO GO WITH MUCH SPECIFICS JUST YET. UPPER JET CORE AND
SUBTLE WAVE WILL NOT BE FULLY SAMPLED UNTIL TOMORROW...AND EVEN THEN
WOULD NOT BE SURPRISED TO SEE GUIDANCE FLUCTUATIONS GIVEN COMPLEXITY
OF MID AND UPPER LEVEL FEATURES AND THEIR INTERACTION. AS OF
NOW...FULL RANGE OF POSSIBILITIES REMAIN VIABLE...FROM A MUCH
FLATTER AND WEAKER SOLUTION REMAINING WELL TO OUR SOUTH...TO A MORE
FULLY ORGANIZED AND DEEP LAYER STORM BRINGING SIGNIFICANT SNOW
ACCUMULATIONS AND IMPACTS TO MUCH...IF NOT ALL...OF NORTHERN
MICHIGAN. AS IS OFTEN THE CASE...REALITY WILL PROBABLY LIE SOMEWHERE
BETWEEN THIS TWO EXTREMES...WHICH WOULD STILL LIKELY DRIVE SOME
ACCUMULATING SNOW TO AT LEAST PARTS OF NORTHERN LOWER MICHIGAN. NO
DOUBT SYSTEM WILL HAVE TO BE CLOSELY MONITORED...WITH THE MORE
WRAPPED UP SCENARIO (E.G. 00Z ECMWF) SHOWING EXCELLENT LIFT IN THE
DGZ...ENHANCED BANDING POTENTIAL VIA FGEN RESPONSE...AND HINTS OF
SOME REDUCED STABILITY ALOFT. WILL BEGIN TO RAMP UP THIS STORM
POTENTIAL IN OUR LATEST HAZARDOUS WEATHER PRODUCTS AND THROUGH OUR
WEB GRAPHICS. DEFINITELY WORTH MONITORING IN THE COMING DAYS FOR
SURE.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 323 PM EST WED NOV 18 2015
DEPENDING ON HOW SATURDAY`S SYSTEM EVOLVES...COULD STILL BE DEALING
WITH AT LEAST LIGHT SYNOPTIC SNOW ACROSS THE SOUTHEASTERN COUNTIES
TO BEGIN THE PERIOD. HOWEVER...AS THE LOW DEPARTS QUICKLY OFF TO THE
NORTH AND EAST...WINDS SHIFT NORTHERLY SATURDAY NIGHT AND EVENTUALLY
WNW BY SUNDAY MORNING. WITH H8 TEMPS PROGGED TO BE ROUGHLY -13C
ACROSS NRN MI AND DELTA TS ~22C...WOULD EXPECT LES TO KICK IN AND
BRIEFLY TARGET AREAS WEST OF THE 131 CORRIDOR INCLUDING THE TRAVERSE
CITY AND CADILLAC AREAS ALONG WITH NRN CHIPPEWA COUNTY BEFORE
SHIFTING TO MORE WNW FLOW FAVORED LOCATIONS OF NORTHWEST LOWER AND
NRN CHIPPEWA BY EARLY SUNDAY MORNING. SUNDAY EVENING...LLEVEL WINDS
SHIFT WESTERLY...THEN WSW SUNDAY NIGHT AIDING IN WARMING H8 TEMPS
AND AN EVENTUAL SHUT OFF TO THE MAJORITY OF LAKE INDUCED SNOW.
HINTS ARE THERE MONDAY THAT ANOTHER WEAK WAVE MAY SLIDE THROUGH
RATHER ZONAL UPPER LEVEL FLOW TIED TO AN ASSOCIATED NRN JET STREAK
ACROSS THE NORTHERN HALF OF THE CWA...PERHAPS PROVIDING ADDITIONAL
SNOW SHOWER CHANCES. GLOBAL GUIDANCE BEGINS TO LARGELY DIVERGE BY
WEDNESDAY WITH SEVERAL SOLUTIONS POSSIBLE...ALTHOUGH ANOTHER WARM UP
LOOKS TO BE ON TAP FOR THE MIDDLE OF NEXT WEEK INTO PERHAPS THE
THANKSGIVING HOLIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1152 PM EST WED NOV 18 2015
...STRONG WINDS AND SHOWERY...
STRONG LOW PRESSURE LIFTS UP THROUGH NW ONTARIO OVER THE NEXT 24
HOURS. A FRONTAL BOUNDARY HAS PUSHED THROUGH NRN MICHIGAN AND A
LOOSER PRESSURE GRADIENT AND DRIER SWATH OF AIR WERE MOVING IN
OVER NRN MICHIGAN. WINDS REMAINED GUSTY HOWEVER...AT 20 TO 30 MPH
AND A PERIOD OF PARTIAL CLEARING WAS MOVING IN. THE NEXT SFC
TROUGH/COLD FRONT WAS PRESSING QUICKLY EAST...AND WILL ARRIVE
AROUND/SHORTLY AFTER DAYBREAK. OVERLAKE INSTABILITY WILL DEVELOP
MVFR CIGS AGAIN BY DAWN OVER THE NW LOWER AIRPORTS...WHILE SKIES
LIKELY REMAIN PARTLY CLOUDY INTO MID MORNING AT APN. THE PRESSURE
GRADIENT TIGHTENS AGAIN THROUGH THE DAY AND EVENING...WITH WINDS
SHIFTING MORE SW/WSW AT REACHING GUSTS IN THE AFTERNOON UP TO 40
TO 45 MPH. THE COLD FRONT WILL BRING PERIODIC LIGHT RAIN SHOWERS
TO PRIMARILY PLN...WHICH WILL CHANGE OVER TO SNOW AND REDUCED
VSBYS LATER IN THE AFTERNOON AND EVENING. MAYBE A HALF OF AN INCH
THURSDAY EVENING.
&&
.MARINE...
ISSUED AT 323 PM EST WED NOV 18 2015
GALE FORCE WINDS AND HIGH WAVES WILL CONTINUE TO IMPACT ALL
NEARSHORE AREAS THRU TONIGHT (AT LEAST) AND AS DEEP LOW PRESSURE
LIFTS NE INTO S CENTRAL CANADA...PRODUCING A TIGHT LOW LEVEL
PRESSURE GRADIENT ACROSS THE WRN GREAT LAKES REGION. WAVES OF
WIDESPREAD RAIN WILL ALSO CONTINUE TO IMPACT OUR AREA THRU
TONIGHT...BECOMING MIX WITH SNOW ON THURSDAY.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...GALE WARNING UNTIL 5 AM EST THURSDAY FOR LHZ346>349.
GALE WARNING UNTIL 7 AM EST FRIDAY FOR LHZ345.
LM...GALE WARNING UNTIL 7 AM EST FRIDAY FOR LMZ323-341-342-344>346.
LS...GALE WARNING UNTIL 5 AM EST THURSDAY FOR LSZ322.
GALE WARNING UNTIL 7 AM EST FRIDAY FOR LSZ321.
&&
$$
UPDATE...DICKSON
NEAR TERM...MLR
SHORT TERM...MSB
LONG TERM...GILLEN
AVIATION...DICKSON
MARINE...MLR
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
629 PM CST FRI NOV 20 2015
.UPDATE...UPDATED FOR THE 00Z DISCUSSION BELOW.
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 321 PM CST FRI NOV 20 2015
THE SHORT TERM CONCERN REMAINS THE SNOW TO THE SOUTH AND ATTENDANT
ADVISORY OVER FAR SOUTH CENTRAL MN.
HEAVY SNOW BAND (1-2 INCHES AN HOUR)MOVING ACROSS NORTHERN IOWA THIS
AFTERNOON WILL CONTINUE TO MOVE EAST/SOUTHEAST MAINLY SOUTH OF THE
MN/IA BORDER THIS EVENING. STILL LOOKS LIKE A 2 TO 4 INCH SNOW EVENT
OVER THE SOUTHERN TIER OF COUNTIES AND WILL CONTINUE THE ADVISORY
UNTIL EXPIRATION AT 03Z. THE SNOW SHOULD END AROUND 06Z OR SO IN
SOUTH CENTRAL MN.
THE UPPER TROUGH WILL BE MOVING THROUGH AS WELL WITH COLDER AIR
SETTLING IN OVER THE AREA LATE TONIGHT AND SATURDAY. HIGH
TEMPERATURES WILL BE LIMITED BY THE SNOW COVER TO THE SOUTH.
THE ENTIRE CWA WILL LIKELY REMAIN IN THE MID-UPPER 20S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 321 PM CST FRI NOV 20 2015
BENIGN WEATHER WILL MARK THE LONG TERM FORECAST UNTIL MID TO LATE
IN THE UPCOMING WEEK.
COLD AND DRY HIGH PRESSURE WILL PREVAIL SATURDAY NIGHT INTO
SUNDAY. TEMPERATURES WILL DIP INTO THE TEENS ACROSS THE
AREA...WITH READINGS AROUND 10 DEGREES ALONG THE IOWA BORDER WITH
THE RELATIVELY FRESH SNOWPACK. WILL HAVE INCREASING CLOUD COVER
OVERNIGHT HOWEVER...SO THE POTENTIAL FOR SINGLE-DIGIT LOWS APPEARS
LOW.
FLOW WILL TURN SOUTHERLY ON SUNDAY...WHICH WILL ALLOW
TEMPERATURES TO MODERATE INTO THE LOWER 30S/40S. THAT WILL BE
SHORT-LIVED HOWEVER...AS A CLIPPER-LIKE SYSTEM SCRAPES NORTHWEST
MINNESOTA AND DIVES ACROSS THE GREAT LAKES ON SUNDAY NIGHT. FOR
MOST OF THE AREA THIS WILL MERELY MEAN INCREASED CLOUD COVER AND A
SLIGHT REDUCTION IN HIGH TEMPERATURES...ALTHOUGH FORCING AND
SUFFICIENT MOISTURE COULD BE FOUND AS FAR SOUTH AS OUR WEST
CENTRAL WI COUNTIES.
RIDGING PREVAILS FOR THE FIRST HALF OF THE UPCOMING WEEK...WITH
MILD AND DRY WEATHER THROUGH TUESDAY NIGHT. AS THIS IS
OCCURRING...MEDIUM RANGE MODELS FORECAST A WESTERN CONUS CLOSED
LOW TO PHASE WITH THE NORTHERN STREAM JET AND FORM INTO A
POSITIVELY TILTED TROUGH AS IT EJECTS EASTWARD INTO THE CENTRAL
CONUS. BOTH ECMWF AND GFS MODELS DEPICT A WINTRY MIX OF RAIN AND
SNOW FOR OUR AREA BEGINNING WEDNESDAY NIGHT. THERE IS STILL
NOTABLE DIFFERENCE FOR THE THANKSGIVING HOLIDAY ON HOW MUCH AND
WHAT TYPE/S/ OF PRECIPITATION WILL FALL GIVEN THE SPATIAL
DIFFERENCES BETWEEN THE GFS AND ECMWF MODELS. AT THIS POINT...THE
HIGHEST AMOUNTS LOOK TO FALL FROM SOUTHERN MN INTO CENTRAL
WI...WITH A RAIN/SNOW MIX POSSIBLE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 619 PM CST FRI NOV 20 2015
WHILE A SNOWSTORM IS ONGOING TO OUR SOUTH...AND THE SNOW HAS
REACHED THE I-90 CORRIDOR...NONE OF THE TAF SITES WILL SEE
ANYTHING OF SIGNIFICANCE FROM THIS SYSTEM. OUR ATTENTION FOR THE
AVIATION FORECAST IS ACTUALLY ON THE AREA OF MVFR STRATUS IN
NORTHERN MN THIS EVENING. THERE ARE VARYING IDEAS OF WHAT TO
EXPECT WITH THIS STRATUS DECK. THE NAM IS VERY PESSIMISTIC IN
SPREADING IT THROUGH OUR AREA OVERNIGHT. THE RAP AND HRRR ARE MUCH
MORE OPTIMISTIC IN SCATTERING THOSE CLOUDS AS THEY MOVE SOUTH.
WILL NEED TO MONITOR THE TRENDS AND HOW THEY MATCH WITH THE
VARIOUS GUIDANCE INITIALIZATIONS. VFR THROUGH THE EVENING...THEN
THE THREAT OF MVFR CIGS MOVE DOWN OVERNIGHT. WENT MORE WITH THE
RAP/HRRR SOLUTIONS FOR NOW.
KMSP...STILL STICKING WITH SCT030 TOMORROW MORNING...BUT THE NAM
INDICATES BKN CEILINGS AT THAT LEVEL. WITH THE HRRR/RAP
DISAGREEING...DID NOT FEEL CONFIDENT ENOUGH TO CHANGE THE FORECAST
AT THIS TIME.
/OUTLOOK FOR KMSP/
SUN...VFR. WIND SW AT 10G20KTS.
MON...VFR. WIND WNW AT 10G15KTS.
TUE...VFR. WIND SE 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY UNTIL 3 AM CST SATURDAY FOR MNZ091>093.
&&
$$
SHORT TERM...DWE
LONG TERM...LS
AVIATION...SPD
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
926 PM MST WED NOV 18 2015
.UPDATE...
A COUPLE MORE UPDATES THIS EVENING. PERSISTENT SNOW BAND OVER
SOUTHERN BIG HORN AND SHERIDAN COUNTIES HAS STRENGTHENED IN THE
PAST HOUR AND LAW ENFORCEMENT REPORTS HALF AN INCH TO AN INCH OF
ACCUMULATION IN SOME AREAS. MODELS NOT HANDLING THIS FEATURE WELL
AT ALL BUT HRRR HAS SOME HINT OF IT AND KEEPS IT IN PLACE UNTIL
MIDNIGHT. ADJUSTED FORECAST POPS UP TO LIKELY AND ADDED AN INCH OF
ADDITIONAL ACCUMULATION TO ACCOUNT FOR POSSIBLY 3 HOURS OF
SNOWFALL. ROADS ARE REPORTEDLY GETTING PRETTY SLICK IN SHERIDAN
INCLUDING I-90 SO ANYONE TRAVELING THAT DIRECTION BE PREPARED FOR
DIFFICULT TRAVEL CONDITIONS.
THAT SNOWBAND APPEARS TO BE THE ONLY TRAVEL CONCERN FOR THE AREA
WITH THE REST OF THE SNOW BANDS WEAKENING IN GENERAL. WINDS
CONTINUE A DOWNWARD TREND TOO AND AS A RESULT TEMPERATURES ARE
REALLY DROPPING ACROSS THE AREA. ALREADY NEAR FORECAST LOWS IN
MANY AREAS SO LOWERED TEMPERATURES 5 TO 8 DEGREES. THIS PUTS MOST
OF THE AREA IN THE TEENS FOR TOMORROW MORNING. CHAMBERS
&&
.SHORT TERM...VALID FOR THU AND FRI...
STRONG UPPER LEVEL DISTURBANCE WAS SEEN DEPARTING TO SOUTHEAST
EARLY THIS MORNING. IN ITS WAKE STRONG WINDS MOVED INTO THE
FORECAST AREA. THE STRONGEST WINDS HAVE MOVED OUT TO EASTERN ZONES
AS OF THIS UPDATE SO NEARLY ALL HIGH WIND WARNINGS HAVE BEEN
CANCELLED EXCEPT FOR WARNINGS IN SHERIDAN...ROSEBUD...SOUTHERN BIG
HORN...CUSTER...CARTER...FALLON...AND POWDER RIVER COUNTIES.
STRONG WINDS IN THESE LOCATIONS SHOULD BEGIN DIMINISHING JUST
AFTER SUNSET AS THE STRONG JET MOVES EAST AND BOUNDARY LAYER
COOLING MAKES IT HARDER FOR STRONG WINDS TO REACH THE
SURFACE...THOUGH CARTER AND FALLON COUNTIES COULD SEE WARNING
CRITERIA WINDS PERSIST UNTIL SUNRISE THURSDAY. EVEN THOUGH WINDS
WILL LESSEN THROUGH THE NIGHT WE STILL EXPECT ELEVATED WINDS UNTIL
SUNRISE AND URGE THAT FOLKS STILL TAKE WIND PRECAUTIONS THROUGH
THURSDAY MORNING.
NORTHWEST FLOW ALOFT TAKES OVER THURSDAY MORNING. A SHORTWAVE
TROUGH FURTHER UPSTREAM WILL QUICKLY AMPLIFY AND DIVE SOUTHEAST
THURSDAY AFTERNOON. WEAK COLD FRONT WILL TURN WINDS NORTHERLY
THURSDAY NIGHT AND ANOTHER ROUND OF COLD AIR ADVECTION...COMBINED
WITH INCREASING MOISTURE ALOFT...WILL ALLOW A QUICK SHOT OF SNOW
FOR MOST OF SOUTHERN MONTANA ON FRIDAY...MOSTLY IN THE MORNING.
WITH A VERY FAST MOVING SYSTEM, AND NOT THE MOST IDEAL
DYNAMICS...I AM NOT EXPECTING HIGH IMPACT ACCUMULATIONS WITH THIS
SYSTEM AT THIS TIME. THERE IS STILL A BIT OF UNCERTAINTY IN THE
PLACEMENT OF THE HIGHEST QPF. ALSO SHOULD NOTE THERE HAS BEEN A
POSITIVE TREND IN PRECIPITATION AMOUNTS OVER SOUTHERN PORTIONS OF
THE FORECAST AREA SO USERS SHOULD BE SURE TO STAY UP TO DATE WITH
OUR FORECAST IN CASE OUR THINKING CHANGES OVER THE NEXT 36 HOURS.
CONDITIONS CLEAR OUT FRIDAY AFTERNOON BUT COOL POST FRONTAL
TEMPERATURES AND CLEAR SKIES WILL ALLOW MOST LOCATIONS TO SEE
THEIR COLDEST TEMPERATURE OF THE SEASON SATURDAY MORNING.
TEMPERATURES WILL REMAIN COOL WITH LOWS IN THE MID TO LOW 20S IN
CENTRAL MONTANA AND IN THE MID TO LOW TEENS OUT EAST AND NEAR
SHERIDAN. DOBBS
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
FOLLOWING THE CLIPPER SYSTEM THURSDAY INTO FRIDAY...THE WEEKEND
SHOULD BE QUIET. THE FLOW WILL BE COME NORTHWESTERLY WITH A RIDGE
DEVELOPING OFF THE COAST OF BRITISH COLUMBIA. THE FLOW WILL
REMAIN GENERALLY NORTHWESTERLY INTO EARLY NEXT WEEK. MONDAY A
TROUGH STARTS TO DEVELOP IN ALASKA AND GOING INTO TUESDAY...WILL
DEVELOP INTO A DEEPENING TROUGH OVER THE WESTERN US. MODELS ARE
COMING INTO BETTER AGREEMENT WITH THIS WAVE...HOWEVER HAVE SHIFTED
AWAY FROM A CLOSED LOW. GFS ENSEMBLE SHOWS REMARKABLE CONSISTENCE
OVER THE WESTERN US EVEN INTO THE MIDDLE OF NEXT WEEK. THE ONE
ISSUE IS THAT MODELS UPSTREAM HAVE MUCH GREATER SPREAD. FOR NOW
HAVE JUST TRENDED TOWARDS LOWER TEMPERATURES AND HAVE KEPT CHANCE
POPS TUESDAY AND WEDNESDAY. REIMER
&&
.AVIATION...
WINDS SHOULD CONTINUE TO DECREASE OVERNIGHT. FLIGHT CONDITIONS
SHOULD REMAIN VFR...ALTHOUGH ISOLD SNOW SHOWERS MAY BRING
LOCALIZED MVFR VISIBILITIES. EXPECT GUSTY WINDS TO RETURN TO THE
LIVINGSTON AREA ON THURSDAY MORNING...WITH GUSTS AROUND 30 KNOTS.
AAG
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 020/040 023/030 017/038 023/046 025/046 027/039 020/030
11/B 66/J 10/N 00/N 01/U 11/B 13/J
LVM 024/036 025/028 020/036 025/043 027/043 029/036 022/026
13/J 75/J 10/N 00/N 11/N 12/W 23/J
HDN 018/040 020/031 012/039 018/047 022/047 024/040 018/032
21/B 66/J 10/B 00/U 01/U 11/B 12/J
MLS 019/038 017/031 009/037 017/047 022/046 022/038 016/031
11/B 32/J 10/B 00/U 00/B 01/B 12/J
4BQ 020/037 018/029 009/037 016/047 022/048 022/044 016/035
20/B 34/J 10/B 00/U 00/U 01/B 12/J
BHK 019/033 012/028 010/033 016/045 022/044 021/039 018/031
10/N 22/J 20/B 00/B 00/B 01/B 12/J
SHR 019/039 019/028 009/038 015/048 022/048 023/042 015/034
61/B 66/J 10/B 00/U 00/U 01/B 12/J
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
837 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 826 PM CST FRI NOV 20 2015
FORECAST WAS UPDATED TO CLEAR HEADLINES...AND REMOVE ALL MENTION
OF PRECIPITATION TONIGHT EXCEPT FOR WHAT IS STILL MOVING THROUGH
THE FAR SOUTHEAST CORNER OF THE FORECAST AREA...BUT EVEN THAT
SHOULD BE DONE SOON. ALSO ADJUSTED TEMPERATURES AND WINDS FOR
TONIGHT BASED ON LATEST OBSERVATIONS. A FEW FLURRIES MAY STILL BE
REPORTED THIS EVENING BUT NO REDUCTIONS TO VISIBILITY EXPECTED.
AT 0230Z THERE WAS ANOTHER SMALL BAND OF VERY LIGHT SNOW OVER THE
NEBRASKA PANHANDLE WITH CHADRON DOWN TO 1.25 MI AND 1 MILE AT
SCOTTS BLUFF. THE 01Z RUNS OF THE THE OPERATIONAL AND
EXPERIMENTAL HRRR BRING THIS LIGHT BAND INTO NORTH CENTRAL-SOUTHWEST
NEBRASKA BY 09Z. THESE MODELS INDICATE THAT BAND SHOULD DISSIPATE
BEFORE MOVING INTO EASTERN NEBRASKA...BUT WE WILL KEEP ON EYE ON
THE TRENDS.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 230 PM CST FRI NOV 20 2015
SNOW CONTINUES TO FALL ACROSS NORTHERN PARTS OF THE AREA EARLY
THIS AFTERNOON WITH HIGHEST AMOUNTS REPORTED ALONG THE NORTHERN
BORDER WHERE SNOW HAS BEEN PERSISTENT SINCE THIS MORNING. LATEST
REGIONAL RADARS SHOW BACK EDGE OF SNOW MOVING QUICKLY EAST INTO
NORTHEAST NEBRASKA AT 19Z WITH COLD FRONT PUSHING SOUTH TOWARD
SOUTHEAST NEBRASKA. MAIN SNOW BAND HAS BEEN ORIENTED ALONG
600-700MB AXIS OF FRONTOGENETIC FORCING SINCE THIS MORNING WITH A
SECONDARY BAND OF PRECIP OVER SOUTHWEST IOWA ALONG THE 800-900MB
AXIS. LATEST SHORT RANGE MODELS SHOW THE MID LEVEL FORCING
BECOMING LESS FOCUSED ALONG THE NORTHERN BORDER AND DRIFTING TO
THE SOUTHEAST THROUGH THE EVENING WHILE LOW LEVEL FORCING DROPS
INTO KANSAS AND MISSOURI AS THE COLD AIR MOVES INTO THE AREA.
WILL CONTINUE WITH CURRENT HEADLINES FOR NOW SINCE WINDS WILL BE
PICKING UP BEHIND THE FRONT. CURRENT SNOW AMOUNTS AND ORIENTATION
ALSO LOOKS PRETTY GOOD WITH AMOUNTS DROPPING OFF QUICKLY SOUTH OF
THE PLATTE RIVER INTO SOUTHWEST CORNER OF IOWA. SYSTEM SHOULD BE
PRETTY MUCH OUT OF THE AREA BY MID TO LATE EVENING.
A PERIOD OF DRY WEATHER FOLLOWS BEHIND THIS SYSTEM FOR SATURDAY INTO
MONDAY. COLD TEMPERATURES WILL BE THE RULE THROUGH SUNDAY MORNING
THEN MODERATING A BIT INTO EARLY NEXT WEEK.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 230 PM CST FRI NOV 20 2015
FIRST PART OF THE WEEK STARTS OFF SEASONAL AND DRY BUT ANOTHER
STORM SYSTEM FROM MID TO LATE WEEK WILL BRING THE CHANCE OF MORE
WINTER WEATHER TO A LARGE PART OF THE REGION FOR THE THANKSGIVING
HOLIDAY.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 520 PM CST FRI NOV 20 2015
IFR CONDITIONS WITH SNOW WILL MOVE OUT THIS EVENING...THEN LOOK
FOR CONDITIONS TO BECOME VFR AT KOFK BY 06Z THEN BETWEEN 08Z AND
10Z FOR KOMA AND KLNK. NORTH WINDS WILL SLOWLY DECREASE.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...NIETFELD
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
709 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 655 PM CST FRI NOV 20 2015
SENT AN UPDATE OUT FOR THIS EVENING...CURTAILING SNOW EARLIER BY 9
AM FOR ALL AREAS AS THE HRRR SEEMS TO HAVE THE BEST GRIP ON LATEST
PRECIPITATION TRENDS AS WELL AS THE RADAR INDICATING THAT MOST
PRECIPITATION IS OUT OF OUR CWA.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 319 PM CST FRI NOV 20 2015
THE MAIN CONCERNS IN THE SHORT TERM FORECAST PERIOD ARE ACTUALLY IN
THE VERY NEAR TERM AS A LARGE UPPER LEVEL DISTURBANCE IS BRINGING
ONGOING PRECIPITATION TO PORTIONS OF NEBRASKA. OTHERWISE THE
REMAINDER OF SHORT TERM IS FAIRLY QUIET AND SEASONABLY COLD.
FOR THE REST OF TODAY...THE UPPER LEVEL TROUGH WILL CONTINUE TO
SURGE EASTWARD ACROSS THE PLAINS...AS A DAUNTING COLD FRONTAL
BOUNDARY SINKS QUICKLY SOUTHEAST. LATEST RADAR TRENDS HAS INDICATED
POCKETS OF HEAVIER PRECIPITATION REMAINING WELL TO THE NORTH OF
INTERSTATE 80 WITH ONLY LIGHT SCATTERED RADAR RETURNS ACROSS THE TRI-
CITIES. OBSERVATIONS AROUND MID AFTERNOON SHOW THE FRONTAL BOUNDARY
HAS SAGGED AS FAR SOUTH AS THE TRI-CITIES. FORECAST SNOW AMOUNTS
COULD BE A BIT HIGH FOR PORTIONS OF POLK COUNTY THIS EVENING.
CHANCES FOR PRECIPITATION WILL LAST THE LONGEST FOR THAT COUNTY AS
THE SYSTEM EXITS. HOWEVER...TEMPERATURES WILL NEED TO WET BULB DOWN
CLOSER TO FREEZING FOR SNOW TO MATERIALIZE. THIS HAPPENED RATHER
QUICKLY ACROSS PORTIONS OF VALLEY AND GREELEY COUNTIES BUT
CONFIDENCE IS RATHER SHAKY FURTHER SOUTHEAST. THUS SNOW AMOUNTS MAY
ACTUALLY BE LOWER THAN FORECAST.
THE COLD FRONT WILL CONTINUE TO SURGE SOUTH THIS EVENING WITH STRONG
NORTHERLY WINDS BEHIND THE FRONT. THIS INCREASED GUSTS COULD LAST
WELL INTO THE OVERNIGHT HOURS BEFORE DECREASING NEAR SUNRISE.
THE FRONT WILL USHER IN MUCH COLDER AIR...IN FACT...PROBABLY THE
COLDEST OF THE SEASON SO FAR. HIGH TEMPERATURES TOMORROW WILL
STRUGGLE TO REACH THE MID TO UPPER 30S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 319 PM CST FRI NOV 20 2015
A COLD SURFACE HIGH PRESSURE SYSTEM WILL SLIDE TO THE SOUTHEAST
SATURDAY NIGHT. TEMPERATURES WILL CONTINUE TO BE COLD SATURDAY
NIGHT. BY SUNDAY MORNING THE WINDS ARE TURNING TO THE WEST AND WITH
WARM ADVECTION AND DOWN SLOPE WINDS...TEMPERATURES SHOULD RECOVER
PRETTY EASILY INTO THE MID 40S TO AROUND 50. WILL HAVE TO WATCH TO
SEE HOW MUCH SNOW FALLS THIS AFTERNOON AND IF IT WILL HAVE ANY
EFFECT ON THE TEMPERATURES ON SUNDAY.
SUNDAY NIGHT THROUGH TUESDAY A WEAK UPPER LEVEL RIDGE MOVES OVER THE
AREA. THE SURFACE HIGH MOVES TO THE EAST AND A SURFACE LOW DEVELOPS
ON THE HIGH PLAINS. WITH WARM ADVECTION AND WINDS TURNING FROM WEST
TO SOUTH...WILL CONTINUE WITH THE WARM TEMPERATURES. READINGS IN THE
50S ARE POSSIBLE DURING THE DAY.
AN UPPER LEVEL WAVE STARTS TO APPROACH THE FORECAST AREA TUESDAY
NIGHT INTO WEDNESDAY. WITH THE SOUTH WINDS ACROSS THE AREA MONDAY
AND TUESDAY THERE IS SOME MOISTURE THAT MOVES NORTH INTO THE
AREA...MOSTLY IN THE EAST. BY WEDNESDAY THE UPPER WAVE IS AFFECTING
THE AREA ENOUGH THAT WITH THE MOISTURE...THERE IS A SMALL CHANCE FOR
SOME LIGHT RAIN...MAINLY NORTH AND EAST IN THE AREA. A COLD FRONT
MOVES INTO THE AREA WEDNESDAY AFTERNOON AND EVENING. THE COLD AIR IS
A LITTLE BEHIND THE FRONT AND DURING THE AFTERNOON EXPECT RAIN.
THE UPPER LEVEL WAVE MOVES INTO THE AREA WEDNESDAY NIGHT AND THE
COLD FRONT MOVES TO THE SOUTH. BY WEDNESDAY NIGHT THE TEMPERATURES
START TO COOL OFF ENOUGH THAT THE PRECIPITATION SHOULD MIX WITH SNOW
FOR MUCH OF THE AREA THEN CHANGE TO SNOW IN THE NORTHWEST. THE
NORTHWEST SHOULD BE COLD ENOUGH DURING THE DAY THURSDAY TO KEEP
SNOW...BUT PORTIONS OF THE AREA COULD HAVE A MIX WITH MOSTLY RAIN IN
THE SOUTHEAST. COLDER AIR CONTINUES TO PUSH INTO THE AREA AND HAVE A
CHANCE FOR SNOW BOTH THURSDAY NIGHT AND FRIDAY. THAT IS THE CURRENT
THINKING. THE ONE MAIN WRENCH IN ALL OF THIS IS THERE IS A TIGHT
TEMPERATURE GRADIENT AT 850MB AS IT MOVES THROUGH THE AREA. THE
CHANGE FROM RAIN TO SNOW COULD CHANGE QUITE A BIT AS THE COLD AIR
COMES IN. ALSO...IF THE TIMING IS OFF A LITTLE BIT IT COULD MAKE
PHASE CHANGE TIMING DIFFERENT AS WELL.
&&
.AVIATION...(FOR THE 00Z KGRI/KEAR TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 555 PM CST FRI NOV 20 2015
SNOW HAS PUSHED EAST AND CEILINGS SHOULD EVENTUALLY IMPROVE. WIND
GUSTS WILL STAY QUITE STRONG FOR MUCH OF THE NIGHT BEHIND A COLD
FRONT. VFR CONDITIONS ARE EXPECTED SATURDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...SALTZMAN
LONG TERM...JCB
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1247 PM EST THU NOV 19 2015
.SYNOPSIS...
THIS AFTERNOON WILL BE MILD AND SHOWERY, JUST AHEAD OF AN
APPROACHING COLD FRONT. ONCE THE FRONT PASSES THE REGION THIS
EVENING, DRIER WEATHER, ALONG WITH CHILLIER, MORE SEASONABLE
TEMPERATURES, WILL FOLLOW OVERNIGHT AND FRIDAY. OUR NEXT CHANCE
FOR SHOWERS IS EXPECTED FOR LATER SATURDAY, AS ANOTHER COLD FRONT
MOVES IN FROM THE NORTHWEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR SHOWS PATCHY AREAS OF RAIN SHOWERS WORKING NORTH TO
NORTHEAST ACROSS CENTRAL NY AND NORTHEAST PA. MODELS AND SPC
MESOANALYSIS PAGE SHOW A LOW-LEVEL JET FROM 50-65 KNOTS ACROSS
CENTRAL AND WESTERN NY AT THIS TIME. THIS LOW-LEVEL JET IS
PROGGED TO TRACK EAST REACHING THE I-81 CORRIDOR BY 18Z AND ERN
NY/WRN NEW ENGLAND BY 00Z AS A CD FRNT PUSHES INTO C NY.
STRONG LOW-LEVEL MOISTURE ADVECTION WILL CONTINUE TO LEAD TO
DESTABLIZATION FORMING SHOWERS AS IT WORKS E. THERE WAS A
TOPOGRAPHICAL COMPONENT TO THE PRECIPITATION AS UPSLOPE AREAS ON
THE STRG SOUTHERLY WINDS WERE SEEING MORE PRECIPITATION COVERAGE
THAN DOWNSLOPE AREAS. HENCE SHOWERS WERE MOST EXTENSIVE IN PARTS
OF NE PA AND NRN NY. USED HRRR RADAR FIELDS TO POPULATE POP GRIDS
THROUGH THE AFTERNOON WHICH ARE IN GOOD AGREEMENT WITH ON-GOING
PRECIP AND TERRAIN EFFECTS.
MODEL SOUNDINGS INTO THE EARLY AFTERNOON SHOW STRONG WINDS OF ABT
50 KNOTS OR SO DOWN TO ABOUT 2000 FEET AGL...THEN THE WINDS
RAPIDLY WEAKEN TO THE SFC LAYER. IRIS MESONET OBS SHOW A FEW
STATIONS WITH GUSTS OVER 40 MPH WITH THE VAST MAJORITY OF STATIONS
IN THE 30S MPH INCLUDING OUR MAJOR AIRPORTS. HENCE IT WILL BE
WINDY BUT BELOW WIND ADVY CRITERIA. AS THE LLJ WORKS E THIS
AFTERNOON WINDS WILL SLACKEN. WILL ISSUE SPS TO COVER FOR OUR NRN
COUNTIES.
WATER VAPOR IMAGERY SHOWS A SHORT WAVE TROF AXIS FROM IA/IL TO THE
DEEP SOUTH WHICH WILL SWING NE LATER THIS AFTERNOON AND EVENING
AND RE-ORGANIZE PRECIP MAINLY E OF I-81 AS IT WORKS NE AHEAD OF
CD FRNT THAT REACHES THE I-81 CORRIDOR BY 00Z. HENCE HAVE CAT
POPS TRACKING NE ACRS NE PA TO CATSKILLS LATER TODAY AND THIS
EVENING.
AFTER THIS WAVE PASSES OVERNIGHT PRECIP WINDS DOWN AND A
SECONDARY CD FRNT MOVES THROUGH WITH A RETURN TO MORE SEASONALLY
CHILLY TEMPERATURES BY FRI AM.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
3 AM UPDATE... A RELATIVELY QUICK EXIT OF THE STEADIER RAINFALL IS
ANTICIPATED THIS EVENING, AS THE SURFACE FRONT SWEEPS TO OUR EAST.
BEHIND THE FRONT, DRY ADVECTION/SINKING MOTION SHOULD LEAD TO AT
LEAST PARTIAL CLEARING FOR MOST OF THE FORECAST AREA. LOWS BY
DAYBREAK SHOULD RANGE FROM THE MID 30S-LOWER 40S.
FRIDAY-SATURDAY LOOKS GENERALLY DRY, AS A SURFACE HIGH AND SHORT-
WAVE RIDGING ALOFT SLIDE ACROSS NY/PA. TEMPERATURES WILL BE
SEASONABLY CHILLY, WITH HIGHS BOTH DAYS MAINLY IN THE 40S, AND
LOWS FRIDAY NIGHT MOSTLY IN THE 20S.
OUR NEXT WEATHER MAKER, IN THE FORM OF ANOTHER COLD FRONTAL
BOUNDARY, WILL BRING A CHANCE OF SHOWERS BY SATURDAY EVENING, AS
IT MOVES IN FROM THE WEST. LATER SATURDAY NIGHT OR EARLY SUNDAY
MORNING, ENOUGH COLD AIR ADVECTION MAY DEVELOP BEHIND THIS SYSTEM,
TO BRING LAKE-EFFECT SNOW SHOWERS TO UPSTATE NY, PERHAPS
IMPACTING SOME OF OUR NORTHERN ZONES. AS FRONTAL TIMING, ALONG
WITH FLOW ORIENTATION AND THE DEGREE OF COOLING POST FRONTAL
PASSAGE, BECOME CLEARER IN THE COMING DAYS, FORECAST DETAILS WILL
ALSO GET FIRMED UP IN THIS REGARD.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
345 AM UPDATE... COLD CYCLONIC FLOW WILL BE WITH US TO START THE
PERIOD SUNDAY, WITH MODEL CONSENSUS 850 MB TEMPERATURES DIPPING
TO -10 TO -12C. THIS SHOULD BE SUFFICIENTLY COLD FOR LAKE-EFFECT
SNOW SHOWERS. EARLY INDICATIONS ARE THAT THE PREVAILING FLOW
DIRECTION WILL BE DUE WESTERLY, PROBABLY KEEPING THE MOST
PERSISTENT ACTIVITY JUST NORTH AND WELL WEST OF OUR FORECAST
AREA. AT THIS JUNCTURE, WE HAVE A CHANCE OF RAIN/SNOW SHOWERS FOR
OUR NORTHERN/FAR WESTERN ZONES, WITH LIKELY PROBABILITIES UP OVER
NORTHERN ONEIDA COUNTY. SOME ACCUMULATIONS ARE CERTAINLY
POSSIBLE, ESPECIALLY ACROSS THE HIGHER TERRAIN. ONCE SMALLER-SCALE
DETAILS, SUCH AS EXACT LOW-LEVEL WIND DIRECTIONS, BECOME MORE
CERTAIN, SO WILL THE POTENTIAL FOR ANY SNOW ACCUMULATIONS.
NEXT WEEK, THERE IS FAIRLY GOOD MODEL AGREEMENT THAT HEIGHTS WILL
RISE OVER TIME ACROSS THE EASTERN U.S., AS A DEEP TROUGH/CLOSED
LOW DIGS INTO THE INTERMOUNTAIN WEST. THIS EVOLUTION SHOULD LEAD
TO MODERATING TEMPERATURES, LIKELY REACHING LEVELS ABOVE NORMAL
AGAIN, AS WE HEAD TOWARDS THE THANKSGIVING HOLIDAY PERIOD.
FAST MOVING, NORTHERN STREAM UPPER WAVES, COULD BRING SOME
RESIDUAL RAIN/SNOW SHOWERS MONDAY INTO EARLY TUESDAY. OTHERWISE,
MUCH OF NEXT WEEK LOOKS DRY, UNDERNEATH A BUILDING RIDGE ALOFT (AS
ALLUDED TO ABOVE).
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
TROF WILL PUSH THRU THE AREA SHRTLY BRINGING INCRSD VSBY AND
CIGS...AND A WIND SHFT TO A MORE SWLY FLOW...AND A BIT GUSTY. COLD
FNT WILL FOLLOW ARND 00Z BRINGING VFR CONDS AND ANOTHER WIND SHFT
TO A MORE WLY AND EVENTUALLY NW FLOW...WITH CONTD GUSTS.
SO...MVFR AND SPOTTY IFR CONDS ATTM WILL IMPROV THRU THE FIRST SIX
HRS OF THE TAF PD...FLWD BY GNRL VFR CONDS WITH GUSTY WINDS THRU
THE END OF THE TAF PD.
.OUTLOOK...
FRI NGT-SAT...VFR.
SAT NGT...COLD FRONTAL PASSAGE WITH RAIN SHOWERS CHANGING TO SNOW
SHOWERS...AND ASSOCIATED POSSIBLE RESTRICTIONS.
SUN THRU MON...RESTRICTIONS AT TIMES IN MIXED SHSN AND
SHRA...MAINLY CENTRAL NY TERMINALS.
TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/MLJ
NEAR TERM...DJN
SHORT TERM...MLJ
LONG TERM...MLJ
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
954 AM EST THU NOV 19 2015
.SYNOPSIS...
THIS AFTERNOON WILL BE MILD AND SHOWERY, JUST AHEAD OF AN
APPROACHING COLD FRONT. ONCE THE FRONT PASSES THE REGION THIS
EVENING, DRIER WEATHER, ALONG WITH CHILLIER, MORE SEASONABLE
TEMPERATURES, WILL FOLLOW OVERNIGHT AND FRIDAY. OUR NEXT CHANCE
FOR SHOWERS IS EXPECTED FOR LATER SATURDAY, AS ANOTHER COLD FRONT
MOVES IN FROM THE NORTHWEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR SHOWS PATCHY AREAS OF RAIN SHOWERS WORKING NORTH TO
NORTHEAST ACROSS CENTRAL NY AND NORTHEAST PA. MODELS AND SPC
MESOANALYSIS PAGE SHOW A LOW-LEVEL JET FROM 50-65 KNOTS ACROSS
CENTRAL AND WESTERN NY AT THIS TIME. THIS LOW-LEVEL JET IS
PROGGED TO TRACK EAST REACHING THE I-81 CORRIDOR BY 18Z AND ERN
NY/WRN NEW ENGLAND BY 00Z AS A CD FRNT PUSHES INTO C NY.
STRONG LOW-LEVEL MOISTURE ADVECTION WILL CONTINUE TO LEAD TO
DESTABLIZATION FORMING SHOWERS AS IT WORKS E. THERE WAS A
TOPOGRAPHICAL COMPONENT TO THE PRECIPITATION AS UPSLOPE AREAS ON
THE STRG SOUTHERLY WINDS WERE SEEING MORE PRECIPITATION COVERAGE
THAN DOWNSLOPE AREAS. HENCE SHOWERS WERE MOST EXTENSIVE IN PARTS
OF NE PA AND NRN NY. USED HRRR RADAR FIELDS TO POPULATE POP GRIDS
THROUGH THE AFTERNOON WHICH ARE IN GOOD AGREEMENT WITH ON-GOING
PRECIP AND TERRAIN EFFECTS.
MODEL SOUNDINGS INTO THE EARLY AFTERNOON SHOW STRONG WINDS OF ABT
50 KNOTS OR SO DOWN TO ABOUT 2000 FEET AGL...THEN THE WINDS
RAPIDLY WEAKEN TO THE SFC LAYER. IRIS MESONET OBS SHOW A FEW
STATIONS WITH GUSTS OVER 40 MPH WITH THE VAST MAJORITY OF STATIONS
IN THE 30S MPH INCLUDING OUR MAJOR AIRPORTS. HENCE IT WILL BE
WINDY BUT BELOW WIND ADVY CRITERIA. AS THE LLJ WORKS E THIS
AFTERNOON WINDS WILL SLACKEN. WILL ISSUE SPS TO COVER FOR OUR NRN
COUNTIES.
WATER VAPOR IMAGERY SHOWS A SHORT WAVE TROF AXIS FROM IA/IL TO THE
DEEP SOUTH WHICH WILL SWING NE LATER THIS AFTERNOON AND EVENING
AND RE-ORGANIZE PRECIP MAINLY E OF I-81 AS IT WORKS NE AHEAD OF
CD FRNT THAT REACHES THE I-81 CORRIDOR BY 00Z. HENCE HAVE CAT
POPS TRACKING NE ACRS NE PA TO CATSKILLS LATER TODAY AND THIS
EVENING.
AFTER THIS WAVE PASSES OVERNIGHT PRECIP WINDS DOWN AND A
SECONDARY CD FRNT MOVES THROUGH WITH A RETURN TO MORE SEASONALLY
CHILLY TEMPERATURES BY FRI AM.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
3 AM UPDATE... A RELATIVELY QUICK EXIT OF THE STEADIER RAINFALL IS
ANTICIPATED THIS EVENING, AS THE SURFACE FRONT SWEEPS TO OUR EAST.
BEHIND THE FRONT, DRY ADVECTION/SINKING MOTION SHOULD LEAD TO AT
LEAST PARTIAL CLEARING FOR MOST OF THE FORECAST AREA. LOWS BY
DAYBREAK SHOULD RANGE FROM THE MID 30S-LOWER 40S.
FRIDAY-SATURDAY LOOKS GENERALLY DRY, AS A SURFACE HIGH AND SHORT-
WAVE RIDGING ALOFT SLIDE ACROSS NY/PA. TEMPERATURES WILL BE
SEASONABLY CHILLY, WITH HIGHS BOTH DAYS MAINLY IN THE 40S, AND
LOWS FRIDAY NIGHT MOSTLY IN THE 20S.
OUR NEXT WEATHER MAKER, IN THE FORM OF ANOTHER COLD FRONTAL
BOUNDARY, WILL BRING A CHANCE OF SHOWERS BY SATURDAY EVENING, AS
IT MOVES IN FROM THE WEST. LATER SATURDAY NIGHT OR EARLY SUNDAY
MORNING, ENOUGH COLD AIR ADVECTION MAY DEVELOP BEHIND THIS SYSTEM,
TO BRING LAKE-EFFECT SNOW SHOWERS TO UPSTATE NY, PERHAPS
IMPACTING SOME OF OUR NORTHERN ZONES. AS FRONTAL TIMING, ALONG
WITH FLOW ORIENTATION AND THE DEGREE OF COOLING POST FRONTAL
PASSAGE, BECOME CLEARER IN THE COMING DAYS, FORECAST DETAILS WILL
ALSO GET FIRMED UP IN THIS REGARD.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
345 AM UPDATE... COLD CYCLONIC FLOW WILL BE WITH US TO START THE
PERIOD SUNDAY, WITH MODEL CONSENSUS 850 MB TEMPERATURES DIPPING
TO -10 TO -12C. THIS SHOULD BE SUFFICIENTLY COLD FOR LAKE-EFFECT
SNOW SHOWERS. EARLY INDICATIONS ARE THAT THE PREVAILING FLOW
DIRECTION WILL BE DUE WESTERLY, PROBABLY KEEPING THE MOST
PERSISTENT ACTIVITY JUST NORTH AND WELL WEST OF OUR FORECAST
AREA. AT THIS JUNCTURE, WE HAVE A CHANCE OF RAIN/SNOW SHOWERS FOR
OUR NORTHERN/FAR WESTERN ZONES, WITH LIKELY PROBABILITIES UP OVER
NORTHERN ONEIDA COUNTY. SOME ACCUMULATIONS ARE CERTAINLY
POSSIBLE, ESPECIALLY ACROSS THE HIGHER TERRAIN. ONCE SMALLER-SCALE
DETAILS, SUCH AS EXACT LOW-LEVEL WIND DIRECTIONS, BECOME MORE
CERTAIN, SO WILL THE POTENTIAL FOR ANY SNOW ACCUMULATIONS.
NEXT WEEK, THERE IS FAIRLY GOOD MODEL AGREEMENT THAT HEIGHTS WILL
RISE OVER TIME ACROSS THE EASTERN U.S., AS A DEEP TROUGH/CLOSED
LOW DIGS INTO THE INTERMOUNTAIN WEST. THIS EVOLUTION SHOULD LEAD
TO MODERATING TEMPERATURES, LIKELY REACHING LEVELS ABOVE NORMAL
AGAIN, AS WE HEAD TOWARDS THE THANKSGIVING HOLIDAY PERIOD.
FAST MOVING, NORTHERN STREAM UPPER WAVES, COULD BRING SOME
RESIDUAL RAIN/SNOW SHOWERS MONDAY INTO EARLY TUESDAY. OTHERWISE,
MUCH OF NEXT WEEK LOOKS DRY, UNDERNEATH A BUILDING RIDGE ALOFT (AS
ALLUDED TO ABOVE).
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
AN OCCLUDED FRONT IS SET TO CARRY WEST TO EAST ACROSS THE
TERMINALS THIS COMING AFTERNOON. WELL AHEAD OF IT...AN UPPER WAVE
WILL IS SPREADING SHOWERS OVER THE AREA. ALSO OCCURRING IN
ADVANCE OF THE FRONT...A STRONG SOUTHERLY 50-60 KT LOW LEVEL JET
WILL CONTINUE TO PRODUCE LOW LEVEL WIND SHEAR FOR ALL TERMINALS
UNTIL FRONTAL PASSAGE. CIG WILL BE MAINLY HIGHER END MVFR /EVEN
VFR KSYR/ AHEAD OF THE FRONT...THEN MOSTLY DIPPING TO FUEL ALT
CIGS AS THE FRONT NEARS. KBGM-KAVP WILL PROBABLY DIP INTO IFR CAT
AROUND FRONTAL PASSAGE. WINDS GENERALLY SE-SSW IN LOWER TEENS WITH
SOME GUSTS 20 KTS OR SO. SW TO W VEERING WILL OCCUR BEHIND THE
FRONT LATE AFTERNOON-EVENING AS WIND SPEED ALSO DIMINISHES.
.OUTLOOK...
FRIDAY-SATURDAY...VFR.
SAT NIGHT...COLD FRONTAL PASSAGE WITH RAIN SHOWERS CHANGING TO
SNOW SHOWERS...AND ASSOCIATED POSSIBLE RESTRICTIONS.
SUN THROUGH MON...RESTRICTIONS AT TIMES IN MIXED SHSN AND SHRA...MAINLY
CENTRAL NY TERMINALS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/MLJ
NEAR TERM...DJN
SHORT TERM...MLJ
LONG TERM...MLJ
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
932 AM EST THU NOV 19 2015
.SYNOPSIS...
A STORM SYSTEM WILL LIFT INTO HUDSON BAY AND PUSH A COLD FRONT
ACROSS OUR REGION TODAY. AHEAD OF THIS FRONT IT WILL BE WARM AND
WINDY WITH SOME SHOWERS...BUT MORE SEASONABLY COOL TEMPERATURES WILL
BUILD INTO THE REGION BEHIND THE FRONT TONIGHT AND FRIDAY. COLDER
WEATHER WILL RETURN THIS WEEKEND WITH SOME LAKE EFFECT SNOW SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
OTHER THAN THE WINDS...IT WILL BE UNSEASONABLY WARM THIS MORNING
WITH TEMPERATURES IN THE 60S IN MOST AREAS. THE LLJ AND A MID-LEVEL
DISTURBANCE WILL GENERATE LIFT AND AN AREA OF SHOWERS. CONSENSUS
QPF SUGGESTS THE STEADIEST SHOWERS WILL BE ACROSS THE EASTERN LAKE
ONTARIO REGION TODAY. QPF HAS BEEN OVERDONE WITH DOWNSLOPE DRYING
THE LIKELY CAUSE. BASED ON THIS HAVE ACCEPTED THE MODEL MEAN
POSITION...BUT HAVE REDUCED AMOUNTS.
THE HRRR AND OTHER HIGH RESOLUTION GUIDANCE ALSO DEVELOPS SOME
SHOWERS ALONG THE FRONT WHICH MAY BRING ANOTHER QUICK ROUND OF
SHOWERS TO AREAS NORTH OF I-90. THE COLD FRONT WILL ENTER WESTERN
NEW YORK AROUND NOON...AND SWEEP FROM W-E DURING THE AFTERNOON
HOURS. THIS WILL BRING COOLER (BUT NOT YET COLD) AIR INTO THE
REGION THIS AFTERNOON AND ALSO BRING AN END TO THE SHOWERS.
COLD AIR ADVECTION WILL CONTINUE TONIGHT FROM A MODERATE WSW FLOW.
THIS AIR MASS IS QUITE DRY WHICH SHOULD SUPPRESS LAKE EFFECT
ACTIVITY...HOWEVER WITH CONSENSUS 850MB TEMPERATURE FORECAST TO DROP
TO AROUND -7C THERE WILL BE QUITE A BIT OF LAKE INDUCED INSTABILITY.
THE MAJORITY OF HIGH RESOLUTION GUIDANCE DOES NOT FORECAST ANY LAKE
EFFECT RAIN OR SNOW SHOWERS...WITH THE RGEM GUIDANCE A NOTABLE
EXCEPTION. GIVEN THE DELTA T VALUES AND THE FAIRLY GOOD TRACK RECORD
OF THE RGEM GUIDANCE CHANCE POPS WILL BE INTRODUCED EAST OF LAKE
ERIE. ANY SHOWERS WOULD START OFF AS RAIN...BUT CHANGE OVER TO SNOW
LATE TONIGHT AS TEMPERATURES COOL. SPEAKING OF TEMPERATURES...NEW
GUIDANCE SUPPORTS COLDER LOW TEMPERATURES FOR TONIGHT...WITH MOST
AREAS EXPECTED TO DROP INTO THE 30S BY DAYBREAK FRIDAY MORNING.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
FRIDAY SURFACE HIGH PRESSURE WILL BULGE NORTHEASTWARD FROM THE LOWER
OHIO VALLEY...AND SPREAD FAIR WEATHER TO THE EASTERN GREAT LAKES
REGION. THERE MAY BE A LITTLE LINGERING LAKE EFFECT
PRECIPITATION EAST OF LAKE ERIE. WHILE TEMPERATURES AT 850 HPA (-6 TO
-8C) WILL BE COOL ENOUGH TO SUPPORT A LAKE EFFECT RESPONSE THE DRIER
AIR ASSOCIATED WITH THE SURFACE HIGH PRESSURE MAY BE JUST ENOUGH TO
PREVENT A BAND OF PRECIPITATION FROM FORMING. FOR NOW WILL CARRY A
LOW CHANCE POP FOR EAST OF LAKE ONTARIO THROUGH THE MORNING HOURS OF
FRIDAY.
THERE WILL REMAIN AN UPPER LEVEL TROUGH OVER THE REGION FRIDAY
MORNING...AND THIS FEATURE WITH ITS COOLER POOL OF AIR ALOFT MAY
ALSO ALLOW FOR SOME CLOUDS TO LINGER ACROSS THE REGION IN ADDITION
TO THE LAKE EFFECT CLOUDS. CLOUDS UNDER THE TROUGH WILL BE MOST
LIKELY TOWARDS THE EAST FOR THE FINGER LAKES AND EASTERN LAKE
ONTARIO REGION. AS THE UPPER LEVEL TROUGH LIFTS NORTHEASTWARD
SUNSHINE SHOULD BECOME WIDESPREAD THROUGH THE AFTERNOON HOURS OF
FRIDAY. IT WILL BE A COOLER DAY FRIDAY...WHEN COMPARED TO RECENT
DAYS...THOUGH THE HIGHS ON FRIDAY WILL ACTUALLY RUN NEAR
NORMAL...WITH HIGHS IN THE LOW TO MID 40S.
BY FRIDAY NIGHT WEAK UPPER LEVEL RIDGING WILL CROSS THE
REGION...WITH THE SURFACE HIGH PASSING JUST TO THE SOUTH OF THE
REGION. THIS SHOULD ALLOW FOR A COOL NIGHT WITH OVERNIGHT LOWS
DROPPING INTO THE LOWER 30S REGION-WIDE.
SATURDAY A RETURN SOUTHEASTERLY FLOW BEHIND THE DEPARTING AREA OF
HIGH PRESSURE WILL ALLOW FOR MILDER AIR TO BRIEFLY RETURN TO THE
REGION. WITHIN THIS WARMING ALOFT THERE WILL BE ENOUGH ISENTROPIC
LIFT TO GENERATE A FAIR AMOUNT OF CLOUDS THROUGH THE DAY. THOUGH
WARMING IN THE MID LEVELS...SURFACE TEMPERATURES WILL BE VERY
SIMILAR TO FRIDAY WITH HIGHS AGAIN IN THE 40S. A FEW LOCATIONS ON
THE LAKE PLAIN SOUTH OF LAKE ONTARIO MAY REACH NEAR 50F AS A
SOUTHEASTERLY DOWNSLOPE FLOW WARMS ACROSS THESE AREAS.
SATURDAY WILL ALSO BECOME BREEZY AS A STORM SYSTEM TAKES A CLASSIC
HIGH WIND TRACK...FROM THE EASTERN CORN BELT STATES SATURDAY MORNING
TO JUST NORTH AND WEST OF LAKE ERIE LATE SATURDAY NIGHT AND LIFTING
INTO SOUTHERN CANADA SUNDAY MORNING. THE GFS IS MOST AGGRESSIVE WITH
THE DEEPENING OF THIS STORM SYSTEM WITH THE GFS20 DETERMINISTIC
MODEL DROPPING THE MSLP FROM 1011 MB SATURDAY MORNING OVER
ILLINOIS TO 989 MB SUNDAY MORNING JUST NORTHEAST OF LAKE
NIPISSING ON THE ONTARIO/QUEBEC BORDER. THE ECMWF ONLY DEEPENS
THIS LOW TO 997 MB SUNDAY MORNING WHILE THE NAM DEEPENS THE LOW TO
1009 MB. ALSO THE GFS ENSEMBLE MEMBERS ARE ALMOST ALL NOT NEARLY
AS DEEP AS THE DETERMINISTIC MODEL...WHICH LEADS TO THE GFS AS AN
OUTLIER THUS FAR FOR THE POTENTIAL WIND EVENT.
THOUGH A CLASSIC TRACK FOR HIGH WINDS...WITH AN ISALLOBARIC COUPLET
PASSING OVER VICINITY OF LAKE ERIE THE LLJ BETWEEN 925 AND 850 HPA
ONLY INCREASES TO ABOUT 45 TO 55 KNOTS...WITH AGAIN THE GFS
STRONGEST WITH THE LOW LEVEL WIND FIELD. WOULD LIKE TO SEE THE LLJ A
BIT STRONGER...AND BETTER MODEL CONSISTENCY...AND NOT THE OUTLIER
MODEL (GFS) AS THE STRONGEST WIND FIELD FOR YET ANOTHER HIGH WIND
EVENT. FOR NOW WILL CONTINUE TO MENTION THE POTENTIAL FOR GUSTY
WINDS IN THE HWO.
THIS STORM SYSTEM WILL BRING A COLD FRONT ACROSS THE REGION SATURDAY
NIGHT. ACCOMPANYING THIS COLD FRONT WILL BE RAIN SHOWERS AND HIGHER
ELEVATION SNOW...WITH A BAND OF PRECIPITATION PASSING ACROSS THE
REGION BEFORE A DRY SLOT BRINGS A TEMPORARY END TO THE
PRECIPITATION. AS THE COLD AIR DEEPENS AND TEMPERATURES AT 850 HPA
FALL TO AROUND -8C...PRECIPITATION SHOULD LARGELY BECOME ALL SNOW BY
SUNDAY MORNING. THIS COMBINED WITH SURFACE TEMPERATURES FALLING INTO
THE LOW TO MID 30S WILL INCREASINGLY SUPPORT SNOW SHOWERS...WITH A
MINOR ACCUMULATION POSSIBLE BY SUNDAY MORNING...MAINLY ACROSS THE
HILLS.
AS THIS COLD AIR DEEPENS OVER THE EASTERN GREAT LAKES ATTENTION WILL
QUICKLY CHANGE FROM THE SYNOPTIC PRECIPITATION ASSOCIATED WITH THE
COLD FRONT AND UPPER LEVEL TROUGH TO LAKE EFFECT PRECIPITATION
POTENTIAL. LAKE TEMPERATURES AVERAGING AROUND 10C SUNDAY...WITH 850
HPA TEMPERATURES FALLING TO AROUND -10C THROUGH THE COURSE OF SUNDAY
AND SUNDAY NIGHT WILL INCREASE LAKE INDUCED EQUILIBRIUM LEVELS TO
ABOUT 12K TO 15K FEET. LAKE EFFECT PRECIPITATION WILL BECOME LIKELY
EAST OF LAKE ERIE BY LATE SATURDAY NIGHT. MORE ON THE LAKE EFFECT
SET-UP IN THE LONG TERM DISCO BELOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS SATURDAY`S LOW MOVES OFF INTO QUEBEC SUNDAY...ALL OF THE
INGREDIENTS APPEAR TO BE IN PLACE FOR A BRIEF BUT POTENTIALLY
SIGNIFICANT LAKE EFFECT EVENT OFF LAKE ERIE IMPACTING THE WESTERN
SOUTHERN TIER AND OFF OF LAKE ONTARIO IMPACTING THE TUG HILL
PLATEAU. ENSEMBLES ARE IN EXCELLENT AGREEMENT ON THE SYNOPTIC SETUP
ACROSS THE REGION WITH A SURFACE/MID-LEVEL LOW LIFTING OFF TO THE
NORTHEAST ACROSS QUEBEC AND A SHARP UPPER LEVEL TROUGH UPSTREAM
ACROSS THE CENTRAL GREAT LAKES. COLD AIR WRAPPING IN BEHIND THE
SURFACE/MID-LEVEL FEATURES WILL ADVECT ACROSS THE LAKES ON WESTERLY
FLOW AND AS 850MB TEMPS FALL TO -10C...EQUILIBRIUM LEVELS WILL CLIMB
ABOVE 15KFT BY DAYBREAK SUNDAY MORNING. WHILE DIURNAL EFFECTS SHOULD
HAMPER BAND DEVELOPMENT TO SOME EXTENT DURING THE DAY ON
SUNDAY...SYNOPTIC LIFT FROM THE UPPER LEVEL TROUGH MAY COMPENSATE
FOR THIS AS IT MOVES THROUGH BY SUNDAY EVENING WITH A BRIEF PERIOD
OF POTENTIAL UPSTREAM CONNECTION OFF OF LAKE HURON AS FLOW VEERS TO
THE WNW LATER IN THE DAY AND INTO SUNDAY EVENING. INCREASING SHEAR
SUNDAY NIGHT AND MONDAY IN THE WAKE OF THE UPPER LEVEL TROUGH
PASSAGE SHOULD BRING AN END TO THE BULK OF THE SNOW BY MONDAY
MORNING OFF OF LAKE ERIE AND AROUND LATER IN THE DAY MONDAY OFF LAKE
ONTARIO. THE THREAT FOR ACCUMULATING LAKE EFFECT SNOW THIS WEEKEND
HAS ALSO BEEN ADDED TO THE HAZARDOUS WEATHER OUTLOOK. THERE WILL BE
SOME UNCERTAINTY AS TO HOW MUCH SNOW...ESPECIALLY EARLY IN THE EVENT
AS TEMPERATURES IN THE MID TO UPPER 30S SUNDAY MAY ALLOW FOR MORE
PLAIN RAIN TO FALL RATHER THAN SNOW. GREATEST SNOWFALL ACCUMULATION
EAST OF BOTH LAKES WILL LIKELY COME SUNDAY NIGHT AND INTO MONDAY
WHEN THE COLD AIR DEEPENS FURTHER.
LINGERING LAKE EFFECT SHOWERS ON LAKE ONTARIO WILL SHIFT NORTH INTO
THE SAINT LAWRENCE VALLEY MONDAY MORNING AND DISSIPATE ALTOGETHER BY
MONDAY AFTERNOON AS BROAD RIDGING AND ANTICYCLONIC FLOW TAKES OVER
ACROSS THE REGION IN THE WAKE OF THE TROUGH. TEMPERATURES WILL START
TO MODERATE ONCE AGAIN MONDAY NIGHT INTO TUESDAY AS THE SURFACE
RIDGE SHIFTS EAST...OPENING UP THE LOWER GREAT LAKES ONCE AGAIN TO
INCREASINGLY MILD SOUTHERLY FLOW AND DRY CONDITIONS. THIS RIDGING
WILL BECOME FURTHER ENTRENCHED ACROSS THE EAST AS A DEEP FULL-
LATITUDE TROUGH DIGS ACROSS THE WESTERN U.S. AND AT THIS POINT IT
APPEARS THAT THE UNSEASONABLY WARM AND DRY WEATHER MAY LAST AT LEAST
THROUGH THE THANKSGIVING HOLIDAY THANKS TO THIS RIDGING WHILE VERY
WET AND UNSETTLED WEATHER WILL PREVAIL JUST TO OUR WEST FROM THE
SOUTHERN PLAINS TO THE WESTERN GREAT LAKES AT THE INTERFACE BETWEEN
THE EASTERN RIDGE AND WESTERN TROUGH.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
DOWNSLOPING HAS KEPT CIGS VFR IN MOST AREAS...WITH MVFR CONDITIONS
AT JHW WHERE DOWNSLOPING HAS LESS OF AN IMPACT.
A COLD FRONT WILL PASS FROM W-E FROM 16Z THROUGH 22Z...WITH DRIER
AIR BEHIND IT LIKELY TO HELP LIFT AND SCATTER CLOUDS AND BRING A
PERIOD OF VFR CONDITIONS. THERE MAY BE SOME LAKE EFFECT CLOUDS OR
SHOWERS TONIGHT E-NE OF THE LAKES...BUT FOR THE MOST PART THIS WILL
NOT IMPACT TAF SITES.
OUTLOOK...
FRIDAY...MAINLY VFR.
SATURDAY...AREAS OF MVFR WITH A CHANCE OF SHOWERS.
SATURDAY NIGHT AND SUNDAY...AREAS OF MVFR/IFR WITH SNOW SHOWERS
LIKELY...ESPECIALLY EAST OF THE LAKES.
MONDAY...VFR...EXCEPT MVFR/IFR POSSIBLE EAST OF THE LAKES WITH
LINGERING LAKE EFFECT SNOW SHOWERS.
&&
.MARINE...
WINDS WILL STILL BE STRONG AHEAD OF THE COLD FRONT...AND THEN AGAIN
BEHIND IT. MARINE HEADLINES HAVE BEEN ADJUSTED WITH A FAIRLY
EXTENDED PERIOD OF SMALL CRAFT ADVISORIES IN MOST AREAS. ONE
POTENTIAL CONCERN IS THAT WINDS MAY BRIEFLY APPROACH GALE BEHIND THE
COLD FRONT THIS EVENING. AT THIS TIME...THIS IS EXPECTED TO BE TOO
BRIEF TO ISSUE ANOTHER GALE WARNING...BUT THIS CAN BE MONITORED ON
FUTURE SHIFTS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 2 AM EST FRIDAY FOR LEZ020.
SMALL CRAFT ADVISORY UNTIL 1 AM EST SATURDAY FOR
LOZ043>045.
SMALL CRAFT ADVISORY UNTIL 10 PM EST FRIDAY FOR LOZ042.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
SLZ022-024.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL/CHURCH
SHORT TERM...THOMAS
LONG TERM...THOMAS/WOOD
AVIATION...APFFEL/CHURCH
MARINE...APFFEL/CHURCH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
709 AM EST THU NOV 19 2015
.SYNOPSIS...
A STORM SYSTEM WILL LIFT INTO HUDSON BAY AND PUSH A COLD FRONT
ACROSS OUR REGION TODAY. AHEAD OF THIS FRONT IT WILL BE WARM AND
WINDY WITH SOME SHOWERS...BUT MORE SEASONABLY COOL TEMPERATURES WILL
BUILD INTO THE REGION BEHIND THE FRONT TONIGHT AND FRIDAY. COLDER
WEATHER WILL RETURN THIS WEEKEND WITH SOME LAKE EFFECT SNOW SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE CORE OF A 60 KT LLJ HAS SHIFTED EAST OF ROCHESTER...RESULTING
IN DIMINISHING (BUT STILL BREEZY) WINDS ACROSS WESTERN NEW YORK.
GUSTS TO 50 MPH ARE STILL POSSIBLE IN JEFFERSON COUNTY WHERE
DOWNSLOPING WILL HELP MIX A PORTION OF THESE WINDS TO THE SURFACE.
ELSEWHERE THE WIND ADVISORY HAD BEEN ALLOWED TO EXPIRE.
OTHER THAN THE WINDS...IT WILL BE UNSEASONABLY WARM THIS MORNING
WITH TEMPERATURES IN THE 60S IN MOST AREAS. THE LLJ AND A MID-LEVEL
DISTURBANCE WILL GENERATE LIFT AND AN AREA OF SHOWERS. CONSENSUS
QPF SUGGESTS THE STEADIEST SHOWERS WILL BE ACROSS THE EASTERN LAKE
ONTARIO REGION TODAY. QPF HAS BEEN OVERDONE WITH DOWNSLOPE DRYING
THE LIKELY CAUSE. BASED ON THIS HAVE ACCEPTED THE MODEL MEAN
POSITION...BUT HAVE REDUCED AMOUNTS.
THE HRRR AND OTHER HIGH RESOLUTION GUIDANCE ALSO DEVELOPS SOME
SHOWERS ALONG THE FRONT WHICH MAY BRING ANOTHER QUICK ROUND OF
SHOWERS TO AREAS NORTH OF I-90. THE COLD FRONT WILL ENTER WESTERN
NEW YORK AROUND NOON...AND SWEEP FROM W-E DURING THE AFTERNOON
HOURS. THIS WILL BRING COOLER (BUT NOT YET COLD) AIR INTO THE
REGION THIS AFTERNOON AND ALSO BRING AN END TO THE SHOWERS.
COLD AIR ADVECTION WILL CONTINUE TONIGHT FROM A MODERATE WSW FLOW.
THIS AIR MASS IS QUITE DRY WHICH SHOULD SUPPRESS LAKE EFFECT
ACTIVITY...HOWEVER WITH CONSENSUS 850MB TEMPERATURE FORECAST TO DROP
TO AROUND -7C THERE WILL BE QUITE A BIT OF LAKE INDUCED INSTABILITY.
THE MAJORITY OF HIGH RESOLUTION GUIDANCE DOES NOT FORECAST ANY LAKE
EFFECT RAIN OR SNOW SHOWERS...WITH THE RGEM GUIDANCE A NOTABLE
EXCEPTION. GIVEN THE DELTA T VALUES AND THE FAIRLY GOOD TRACK RECORD
OF THE RGEM GUIDANCE CHANCE POPS WILL BE INTRODUCED EAST OF LAKE
ERIE. ANY SHOWERS WOULD START OFF AS RAIN...BUT CHANGE OVER TO SNOW
LATE TONIGHT AS TEMPERATURES COOL. SPEAKING OF TEMPERATURES...NEW
GUIDANCE SUPPORTS COLDER LOW TEMPERATURES FOR TONIGHT...WITH MOST
AREAS EXPECTED TO DROP INTO THE 30S BY DAYBREAK FRIDAY MORNING.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
FRIDAY SURFACE HIGH PRESSURE WILL BULGE NORTHEASTWARD FROM THE LOWER
OHIO VALLEY...AND SPREAD FAIR WEATHER TO THE EASTERN GREAT LAKES
REGION. THERE MAY BE A LITTLE LINGERING LAKE EFFECT
PRECIPITATION EAST OF LAKE ERIE. WHILE TEMPERATURES AT 850 HPA (-6 TO
-8C) WILL BE COOL ENOUGH TO SUPPORT A LAKE EFFECT RESPONSE THE DRIER
AIR ASSOCIATED WITH THE SURFACE HIGH PRESSURE MAY BE JUST ENOUGH TO
PREVENT A BAND OF PRECIPITATION FROM FORMING. FOR NOW WILL CARRY A
LOW CHANCE POP FOR EAST OF LAKE ONTARIO THROUGH THE MORNING HOURS OF
FRIDAY.
THERE WILL REMAIN AN UPPER LEVEL TROUGH OVER THE REGION FRIDAY
MORNING...AND THIS FEATURE WITH ITS COOLER POOL OF AIR ALOFT MAY
ALSO ALLOW FOR SOME CLOUDS TO LINGER ACROSS THE REGION IN ADDITION
TO THE LAKE EFFECT CLOUDS. CLOUDS UNDER THE TROUGH WILL BE MOST
LIKELY TOWARDS THE EAST FOR THE FINGER LAKES AND EASTERN LAKE
ONTARIO REGION. AS THE UPPER LEVEL TROUGH LIFTS NORTHEASTWARD
SUNSHINE SHOULD BECOME WIDESPREAD THROUGH THE AFTERNOON HOURS OF
FRIDAY. IT WILL BE A COOLER DAY FRIDAY...WHEN COMPARED TO RECENT
DAYS...THOUGH THE HIGHS ON FRIDAY WILL ACTUALLY RUN NEAR
NORMAL...WITH HIGHS IN THE LOW TO MID 40S.
BY FRIDAY NIGHT WEAK UPPER LEVEL RIDGING WILL CROSS THE
REGION...WITH THE SURFACE HIGH PASSING JUST TO THE SOUTH OF THE
REGION. THIS SHOULD ALLOW FOR A COOL NIGHT WITH OVERNIGHT LOWS
DROPPING INTO THE LOWER 30S REGION-WIDE.
SATURDAY A RETURN SOUTHEASTERLY FLOW BEHIND THE DEPARTING AREA OF
HIGH PRESSURE WILL ALLOW FOR MILDER AIR TO BRIEFLY RETURN TO THE
REGION. WITHIN THIS WARMING ALOFT THERE WILL BE ENOUGH ISENTROPIC
LIFT TO GENERATE A FAIR AMOUNT OF CLOUDS THROUGH THE DAY. THOUGH
WARMING IN THE MID LEVELS...SURFACE TEMPERATURES WILL BE VERY
SIMILAR TO FRIDAY WITH HIGHS AGAIN IN THE 40S. A FEW LOCATIONS ON
THE LAKE PLAIN SOUTH OF LAKE ONTARIO MAY REACH NEAR 50F AS A
SOUTHEASTERLY DOWNSLOPE FLOW WARMS ACROSS THESE AREAS.
SATURDAY WILL ALSO BECOME BREEZY AS A STORM SYSTEM TAKES A CLASSIC
HIGH WIND TRACK...FROM THE EASTERN CORN BELT STATES SATURDAY MORNING
TO JUST NORTH AND WEST OF LAKE ERIE LATE SATURDAY NIGHT AND LIFTING
INTO SOUTHERN CANADA SUNDAY MORNING. THE GFS IS MOST AGGRESSIVE WITH
THE DEEPENING OF THIS STORM SYSTEM WITH THE GFS20 DETERMINISTIC
MODEL DROPPING THE MSLP FROM 1011 MB SATURDAY MORNING OVER
ILLINOIS TO 989 MB SUNDAY MORNING JUST NORTHEAST OF LAKE
NIPISSING ON THE ONTARIO/QUEBEC BORDER. THE ECMWF ONLY DEEPENS
THIS LOW TO 997 MB SUNDAY MORNING WHILE THE NAM DEEPENS THE LOW TO
1009 MB. ALSO THE GFS ENSEMBLE MEMBERS ARE ALMOST ALL NOT NEARLY
AS DEEP AS THE DETERMINISTIC MODEL...WHICH LEADS TO THE GFS AS AN
OUTLIER THUS FAR FOR THE POTENTIAL WIND EVENT.
THOUGH A CLASSIC TRACK FOR HIGH WINDS...WITH AN ISALLOBARIC COUPLET
PASSING OVER VICINITY OF LAKE ERIE THE LLJ BETWEEN 925 AND 850 HPA
ONLY INCREASES TO ABOUT 45 TO 55 KNOTS...WITH AGAIN THE GFS
STRONGEST WITH THE LOW LEVEL WIND FIELD. WOULD LIKE TO SEE THE LLJ A
BIT STRONGER...AND BETTER MODEL CONSISTENCY...AND NOT THE OUTLIER
MODEL (GFS) AS THE STRONGEST WIND FIELD FOR YET ANOTHER HIGH WIND
EVENT. FOR NOW WILL CONTINUE TO MENTION THE POTENTIAL FOR GUSTY
WINDS IN THE HWO.
THIS STORM SYSTEM WILL BRING A COLD FRONT ACROSS THE REGION SATURDAY
NIGHT. ACCOMPANYING THIS COLD FRONT WILL BE RAIN SHOWERS AND HIGHER
ELEVATION SNOW...WITH A BAND OF PRECIPITATION PASSING ACROSS THE
REGION BEFORE A DRY SLOT BRINGS A TEMPORARY END TO THE
PRECIPITATION. AS THE COLD AIR DEEPENS AND TEMPERATURES AT 850 HPA
FALL TO AROUND -8C...PRECIPITATION SHOULD LARGELY BECOME ALL SNOW BY
SUNDAY MORNING. THIS COMBINED WITH SURFACE TEMPERATURES FALLING INTO
THE LOW TO MID 30S WILL INCREASINGLY SUPPORT SNOW SHOWERS...WITH A
MINOR ACCUMULATION POSSIBLE BY SUNDAY MORNING...MAINLY ACROSS THE
HILLS.
AS THIS COLD AIR DEEPENS OVER THE EASTERN GREAT LAKES ATTENTION WILL
QUICKLY CHANGE FROM THE SYNOPTIC PRECIPITATION ASSOCIATED WITH THE
COLD FRONT AND UPPER LEVEL TROUGH TO LAKE EFFECT PRECIPITATION
POTENTIAL. LAKE TEMPERATURES AVERAGING AROUND 10C SUNDAY...WITH 850
HPA TEMPERATURES FALLING TO AROUND -10C THROUGH THE COURSE OF SUNDAY
AND SUNDAY NIGHT WILL INCREASE LAKE INDUCED EQUILIBRIUM LEVELS TO
ABOUT 12K TO 15K FEET. LAKE EFFECT PRECIPITATION WILL BECOME LIKELY
EAST OF LAKE ERIE BY LATE SATURDAY NIGHT. MORE ON THE LAKE EFFECT
SET-UP IN THE LONG TERM DISCO BELOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS SATURDAY`S LOW MOVES OFF INTO QUEBEC SUNDAY...ALL OF THE
INGREDIENTS APPEAR TO BE IN PLACE FOR A BRIEF BUT POTENTIALLY
SIGNIFICANT LAKE EFFECT EVENT OFF LAKE ERIE IMPACTING THE WESTERN
SOUTHERN TIER AND OFF OF LAKE ONTARIO IMPACTING THE TUG HILL
PLATEAU. ENSEMBLES ARE IN EXCELLENT AGREEMENT ON THE SYNOPTIC SETUP
ACROSS THE REGION WITH A SURFACE/MID-LEVEL LOW LIFTING OFF TO THE
NORTHEAST ACROSS QUEBEC AND A SHARP UPPER LEVEL TROUGH UPSTREAM
ACROSS THE CENTRAL GREAT LAKES. COLD AIR WRAPPING IN BEHIND THE
SURFACE/MID-LEVEL FEATURES WILL ADVECT ACROSS THE LAKES ON WESTERLY
FLOW AND AS 850MB TEMPS FALL TO -10C...EQUILIBRIUM LEVELS WILL CLIMB
ABOVE 15KFT BY DAYBREAK SUNDAY MORNING. WHILE DIURNAL EFFECTS SHOULD
HAMPER BAND DEVELOPMENT TO SOME EXTENT DURING THE DAY ON
SUNDAY...SYNOPTIC LIFT FROM THE UPPER LEVEL TROUGH MAY COMPENSATE
FOR THIS AS IT MOVES THROUGH BY SUNDAY EVENING WITH A BRIEF PERIOD
OF POTENTIAL UPSTREAM CONNECTION OFF OF LAKE HURON AS FLOW VEERS TO
THE WNW LATER IN THE DAY AND INTO SUNDAY EVENING. INCREASING SHEAR
SUNDAY NIGHT AND MONDAY IN THE WAKE OF THE UPPER LEVEL TROUGH
PASSAGE SHOULD BRING AN END TO THE BULK OF THE SNOW BY MONDAY
MORNING OFF OF LAKE ERIE AND AROUND LATER IN THE DAY MONDAY OFF LAKE
ONTARIO. THE THREAT FOR ACCUMULATING LAKE EFFECT SNOW THIS WEEKEND
HAS ALSO BEEN ADDED TO THE HAZARDOUS WEATHER OUTLOOK. THERE WILL BE
SOME UNCERTAINTY AS TO HOW MUCH SNOW...ESPECIALLY EARLY IN THE EVENT
AS TEMPERATURES IN THE MID TO UPPER 30S SUNDAY MAY ALLOW FOR MORE
PLAIN RAIN TO FALL RATHER THAN SNOW. GREATEST SNOWFALL ACCUMULATION
EAST OF BOTH LAKES WILL LIKELY COME SUNDAY NIGHT AND INTO MONDAY
WHEN THE COLD AIR DEEPENS FURTHER.
LINGERING LAKE EFFECT SHOWERS ON LAKE ONTARIO WILL SHIFT NORTH INTO
THE SAINT LAWRENCE VALLEY MONDAY MORNING AND DISSIPATE ALTOGETHER BY
MONDAY AFTERNOON AS BROAD RIDGING AND ANTICYCLONIC FLOW TAKES OVER
ACROSS THE REGION IN THE WAKE OF THE TROUGH. TEMPERATURES WILL START
TO MODERATE ONCE AGAIN MONDAY NIGHT INTO TUESDAY AS THE SURFACE
RIDGE SHIFTS EAST...OPENING UP THE LOWER GREAT LAKES ONCE AGAIN TO
INCREASINGLY MILD SOUTHERLY FLOW AND DRY CONDITIONS. THIS RIDGING
WILL BECOME FURTHER ENTRENCHED ACROSS THE EAST AS A DEEP FULL-
LATITUDE TROUGH DIGS ACROSS THE WESTERN U.S. AND AT THIS POINT IT
APPEARS THAT THE UNSEASONABLY WARM AND DRY WEATHER MAY LAST AT LEAST
THROUGH THE THANKSGIVING HOLIDAY THANKS TO THIS RIDGING WHILE VERY
WET AND UNSETTLED WEATHER WILL PREVAIL JUST TO OUR WEST FROM THE
SOUTHERN PLAINS TO THE WESTERN GREAT LAKES AT THE INTERFACE BETWEEN
THE EASTERN RIDGE AND WESTERN TROUGH.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
A 50-60 LLJ FROM ROC-ART WILL MOVE EAST OF THE AREA AROUND 16Z.
THIS HAS STRUGGLED TO MIX TO THE SURFACE...BUT THERE STILL MAY BE
SOME HIGHER GUSTS AT ART. THIS HAS RESULTED IN SOME WIND
SHEAR...BUT THUS FAR MIXING HAS BEEN AMPLE KEEP THIS SHY OF LLWS
CRITERIA IN THE TAFS. OTHERWISE...DOWNSLOPING HAS KEPT CIGS VFR
IN MOST AREAS...WITH MVFR CONDITIONS AT JHW WHERE DOWNSLOPING HAS
LESS OF AN IMPACT.
A COLD FRONT WILL PASS FROM W-E FROM 16Z THROUGH 22Z...WITH DRIER
AIR BEHIND IT LIKELY TO HELP LIFT AND SCATTER CLOUDS AND BRING A
PERIOD OF VFR CONDITIONS. THERE MAY BE SOME LAKE EFFECT CLOUDS OR
SHOWERS TONIGHT E-NE OF THE LAKES...BUT FOR THE MOST PART THIS WILL
NOT IMPACT TAF SITES.
OUTLOOK...
FRIDAY...MAINLY VFR.
SATURDAY...AREAS OF MVFR WITH A CHANCE OF SHOWERS.
SATURDAY NIGHT AND SUNDAY...AREAS OF MVFR/IFR WITH SNOW SHOWERS
LIKELY...ESPECIALLY EAST OF THE LAKES.
MONDAY...VFR...EXCEPT MVFR/IFR POSSIBLE EAST OF THE LAKES WITH
LINGERING LAKE EFFECT SNOW SHOWERS.
&&
.MARINE...
STRONG SOUTHERLY WINDS HAVE DROPPED ENOUGH TO ALLOW THE GALES TO
EXPIRE ON LAKE ERIE. WINDS WILL STILL BE STRONG AHEAD OF THE COLD
FRONT...AND THEN AGAIN BEHIND IT. MARINE HEADLINES HAVE BEEN
ADJUSTED WITH A FAIRLY EXTENDED PERIOD OF SMALL CRAFT ADVISORIES IN
MOST AREAS. ONE POTENTIAL CONCERN IS THAT WINDS MAY BRIEFLY APPROACH
GALE BEHIND THE COLD FRONT THIS EVENING. AT THIS TIME...THIS IS
EXPECTED TO BE TOO BRIEF TO ISSUE ANOTHER GALE WARNING...BUT THIS
CAN BE MONITORED ON FUTURE SHIFTS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WIND ADVISORY UNTIL 10 AM EST THIS MORNING FOR NYZ007.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST FRIDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 2 AM EST FRIDAY FOR LEZ020.
SMALL CRAFT ADVISORY UNTIL 1 AM EST SATURDAY FOR
LOZ043>045.
SMALL CRAFT ADVISORY UNTIL 10 PM EST FRIDAY FOR LOZ042.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
SLZ022-024.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...THOMAS
LONG TERM...THOMAS/WOOD
AVIATION...APFFEL
MARINE...APFFEL
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
118 AM EST THU NOV 19 2015
.SYNOPSIS...
A LOW PRESSURE SYSTEM OVER THE WESTERN GREAT LAKES WILL PUSH A
COLD FRONT THROUGH OUR AREA THURSDAY, BRINGING WINDY CONDITIONS
WITH RAIN SHOWERS. COOLER AIR WILL FOLLOW THE FRONT FOR THE
WEEKEND WITH RAIN AND SNOW SHOWERS.
&&
.NEAR TERM /THROUGH TODAY/...
9 PM UPDATE...
AS FORECAST BY THE PREVIOUS SHIFT, THE SHOWER ACTIVITY IS SPARSE
AND STILL A WAYS OFF, DESPITE THE AGGRESSIVE PUSH NORTHEASTWARD BY
A PRIOR HRRR RUN.
MAIN CHANGE FOR THE OVERNIGHT PERIOD WAS TO INCREASE TEMPERATURES
TOWARD SUNRISE, AS WARM AIR IS MAKING A STRONG PUSH OUT OF PA INTO
SWRN NY.
4 PM UPDATE...
TGT GRADIENT WILL KEEP THE LOW CLDS AND WINDS UP OVRNGT...BUT THE
BULK OF THE SHWRS WILL HOLD OFF UNTIL THU. LOW CLDS CONT TO STREAM
NWRD WITH THE LL MOIST FLOW OFF THE WRN ATLANTIC. DOWNSLOPING HAS
LIMITED THE CLDS IN THE MOHAWK VALLEY INTO THE SYR AREA...BUT XPCT
THE CLDS TO EXPAND OVRNGT INTO THOSE AREAS. SC DECK HAS HELPED
MAINTAIN A MORE STABLE LYR NEARER THE SFC AND LIMITED THE AMT OF
HIGH WINDS THAT HAVE BEEN SEEN AT THE SFC. XPCT THIS TO CONT
OVRNGT WITH HEALTHY 40 KT GUSTS ZIPPING ALONG ABV. HIGHEST GUSTS
WILL CONT TO BE OVER THE HIGHER RIDGES OF THE FINGER LAKES...ESP
IN THE WEST.
WITH THE SHRP RDG HOLDING IN THE EAST AND THE UPR LOW WELL WEST
OVER ERN MN...RAIN WILL HOLD OFF FOR MUCH OF THE NGT...OTR THAN A
FEW SPRINKLES OVER THE EAST AND SOUTH. LTR TNGT...SHRT WV AND
DVLPG JET MAX WILL GENERATE A GOOD AREA OF PCPN PUSHING INTO THE
WRN ZONES ARND 09Z...AND CONTG TO SPREAD EAST.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
SOLID AREA OF PCPN MARCHES EAST ON SAT WITH THE WV AND UPR JET.
CAT POPS SEEM RSNBL GIVEN THE CONFIDENCE IN THE ABILITY OF THE FNT
TO GENERATE RAIN...AND THE HISTORY OF THE SYSTEM. FNT AND UPR
SUPPORT IS PROGRESSIVE AND WILL MSTLY BE EAST OF THE AREA BY 00Z
FRI. RAINFALL AMTS SHD NOT BE EXCESSIVE WITH THE MVMT AND SPEED OF
THE FNT...GNRLY LESS THAN 3/4 INCH.
IN THE WAKE OF THE FNT AND WV...AREA REMAINS IN A BROAD UPR TROF
CNTRD OVER CNTRL LAKES. SWLY FLOW CONTS THRU THE END OF THE SHRT
TERM. WITH MRNGL H8 TEMPS AND FLOW DIRECTION NOT FVRBL FOR THE
FCST AREA...XPCT VERY LIMITED LE SHWRS THRU SAT...WITH THE BEST
CHANCE FOR ISLTD RAINS SHWRS OVER THE FINGER LAKES.
TEMPS WILL DROP CONSIDERABLY AFT THU BUT STILL MAY BE SLGTLY ABV
NRML FOR MID NOV.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A SHORTWAVE TROUGH WILL START TO MOVE THROUGH THE REGION SATURDAY
EVENING AND FORCE A SFC LOW ACROSS THE AREA. THIS SYSTEM WILL BRING
COOLER TEMPS ALONG WITH THE CHANCE FOR RAIN/SNOW SHOWERS. THE UPPR
LVL TROUGH WILL SLOWLY MOVE EAST AND SHIFT EAST OF THE REGION BY
MONDAY EVENING. LAKE EFFECT SHOWERS WILL FOLLOW IN THE SYSTEM`S
WAKE. HIGH PRESSURE WILL BUILD OVER CENTRAL NY AND NORTHEAST PA ON
TUESDAY PUTTING AN END TOWARDS SHOWERS OVER THE REGION. LARGE
DISCREPANCIES EXIST WITHIN GUIDANCE STARTING THURSDAY OF NEXT WEEK
THROUGH THE EXTENDED PORTION OF THE FORECAST. DECIDED TO KEEP THE
FORECAST DRY AS CONFIDENCE IS LOW ON ANY SOLUTION.
TEMPS DURING THE FORECAST PERIOD WILL BE CLOSE TO THE SEASONAL
AVERAGE.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AN OCCLUDED FRONT IS SET TO CARRY WEST TO EAST ACROSS THE
TERMINALS THIS COMING AFTERNOON. WELL AHEAD OF IT...AN UPPER WAVE
WILL SPREAD SHOWERS OVER THE AREA. ALSO OCCURRING IN ADVANCE OF
THE FRONT...A STRONG SOUTHERLY 50-60 KT LOW LEVEL JET WILL
CONTINUE TO PRODUCE LOW LEVEL WIND SHEAR FOR ALL TERMINALS FOR THE
REMAINDER OF THE NIGHT INTO EARLY MORNING...AND FOR KSYR-KRME
EVEN UP TO ABOUT MIDDAY. CIGS WILL BE MAINLY MVFR...INTO FUEL ALT
REQ LEVELS FOR KBGM-KITH-KELM-KAVP WHILE MAINLY HIGHER END MVFR
KSYR-KRME AHEAD OF THE FRONT. KBGM-KAVP WILL PROBABLY DIP INTO
IFR CAT AROUND FRONTAL PASSAGE LATE AFTERNOON-EARLY EVENING WITHIN
ROUND OF HEAVIER SHOWERS...WHILE KSYR-KRME SHOULD REACH FUEL ALT
CIGS WITH THE FRONT. WINDS GENERALLY SSE-SSW IN LOW TO MID TEENS
WITH GUSTS IN THE 20S KTS RANGE...EXCEPT FOR LOCALIZED ESE AT
KRME AROUND 12 KTS. SW TO W VEERING WILL OCCUR BEHIND THE FRONT
LATE AFTERNOON-EVENING AS WIND SPEED ALSO DIMINISHES.
.OUTLOOK...
FRIDAY-SATURDAY...VFR.
SAT NIGHT...COLD FRONTAL PASSAGE WITH RAIN SHOWERS CHANGING TO
SNOW SHOWERS...AND ASSOCIATED POSSIBLE RESTRICTIONS.
SUN THROUGH MON...RESTRICTIONS AT TIMES IN MIXED SHSN AND SHRA...MAINLY
CENTRAL NY TERMINALS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...DGM/DJP
SHORT TERM...DGM
LONG TERM...KAH
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
100 PM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA LATE THIS
AFTERNOON AND EARLY THIS EVENING. HIGH PRESSURE WILL BUILD OVER THE
REGION ON FRIDAY. ANOTHER MAINLY DRY COLD FRONT WILL SWEEP ACROSS
THE AREA LATE SATURDAY NIGHT. COOL HIGH PRESSURE RETURNS SUNDAY...
LASTING THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 AM THURSDAY...
WIDESPREAD MODERATE SHOWERS WITH EMBEDDED STORMS PERSIST OVER THE
ERN CWA. PONDING OF WATER ON STREETS AND OTHER FLOODING OF URBAN AND
LOW LYING AREAS HAS BEEN COMMON WITH RAINFALL RATES UP TO 1-2" PER
HOUR. INSTABILITY THUS FAR HAS BEEN MEAGER... ALTHOUGH MUCAPE VALUES
OF 100-250 J/KG (WHICH APPEARS TO BE MOSTLY RESTRICTED TO THE MID
AND HIGH LEVELS) COMBINED WITH STRONG FOCUSED UPPER DIVERGENCE HAS
BEEN SUFFICIENT FOR NUMEROUS LIGHTNING FLASHES (MOSTLY POSITIVE
STRIKES) WITHIN THE HEAVIER SHOWERS. LOW LEVEL SHEAR OF 30-40 KTS
HERE WITH 0-1 SRH VALUES OVER 300 M2/S2 WARRANTS CLOSE MONITORING
FOR ANY ENHANCED WIND SIGNATURES OR WEAK ROTATION OVER OUR SE OVER
THE NEXT FEW HOURS. OTHERWISE... WINDS ALOFT WILL SLOWLY VEER TO
MORE SW AS THE 850-700 MB TROUGH AXES ROTATE NE THROUGH ERN NC...
AND AS THE VERY HIGH PW AND LOW LEVEL MOISTURE TRANSPORT TRANSLATE
SLOWLY NORTHEASTWARD INTO THE AFTERNOON... RAINFALL WILL SLOWLY
TAPER DOWN FROM WEST TO EAST. WATER VAPOR IMAGERY SHOWS A VERY
PRONOUNCED BACK EDGE TO THE DEEPER MOISTURE BUT WITH A STEERING FLOW
HOLDING ROUGHLY PARALLEL TO THE SURFACE FRONTAL ZONE (WHICH IS
ANALYZED OVER FAR WRN NC) AND ANOTHER MID LEVEL VORTICITY LOBE STILL
TO COME THROUGH THIS AFTERNOON... IT WILL TAKE UNTIL LATER TODAY FOR
THE SURFACE FRONTAL ZONE TO BE PROPELLED NORTHEASTWARD THROUGH
CENTRAL NC. LOW LEVEL MOISTURE SHOULD HOLD OVER MUCH OF CENTRAL NC
BEHIND THE MAIN RAIN SHIELD WITH A DELAY IN DOWNSLOPE LOW LEVEL
FLOW... WHICH WILL KEEP A CHANCE OF SHALLOW SHOWERS AREAWIDE THROUGH
MUCH OF THE AFTERNOON... ALONG WITH A BRIEF FOG THREAT WHERE SURFACE
WINDS EAST OF THE MOUNTAINS BECOME LIGHT AND VARIABLE FOR A TIME
AHEAD OF THE FRONT. EXPECT HIGHS FROM AROUND 70 TO THE MID 70S... IN
LINE WITH HI-RES RAPID UPDATE GUIDANCE. -GIH
PREVIOUS DISCUSSION AS OF 410 AM THURSDAY: A LARGE AREA OF RAIN...
WITH A FEW EMBEDDED CONVECTIVE ELEMENTS...IS CURRENTLY TRANSLATING
EAST ACROSS THE FORECAST AREA AS A 50KT PREFRONTAL LOW-LEVEL JET
LIFTS NORTH TOWARD THE MID-ATLANTIC STATES 9PER REGIONAL VWP). THE
CONVECTIVE ELEMENTS LACK ANY LIGHTNING OR STRONG WIND SIGNATURES...
AND GIVEN THE LACK OF ANALYZED INSTABILITY NORTH OF THE SAVANNAH
RIVER BASIN...WE MAY BE FREE OF THUNDERSTORMS FOR THE EARLY MORNING
HOURS. LATER THIS MORNING...VEERING SURFACE WINDS AHEAD OF THE MAIN
COLD FRONT...WHICH IS CURRENTLY MOVING THROUGH NORTHERN GEORGIA AND
EASTERN TN/KY...SHOULD TAP INTO NEAR 70 DEWPOINT AIR OVER EAST-
CENTRAL SC AND LEAD TO SOME WEAK DESTABILIZATION (250-500 J/KG
MLCAPE) FROM THE SANDHILLS INTO THE COASTAL PLAIN BY MIDDAY. THERE
IS NO REAL CONSENSUS IN NEAR TERM GUIDANCE REGARDING THE COVERAGE OF
ADDITIONAL SHOWERS AND STORMS...SOME SHOW A BROKEN LINE AND SOME
SHOW JUST SCATTERED CONVECTION. THE BACK EDGE TO THE DEEP MOISTURE
IS RAPIDLY PUSHING EAST ACROSS THE MOUNTAINS AND IS OUTPACING THE
COLD FRONT....SO DEEP MOISTURE WILL BE LACKING BY THE TIME THE FRONT
ARRIVES. HOWEVER...THE RAP SHOWS A PRE-FRONTAL TROUGH THAT MAY
PROVIDE A FOCUS FOR SOME SCATTERED CONVECTION...MAINLY US 1 AND EAST
BY MIDDAY...AND A FEW ADDITIONAL SHOWERS EVEN POSSIBLE WITH THE
PRIMARY COLD FRONT LATER THIS AFTERNOON AND EVENING. IF SOME
MODERATELY DEEP CONVECTION CAN INITIATE TODAY...0-6KM BULK SHEAR
VALUES OF 35-45KT WOULD CERTAINLY SUPPORT A DAMAGING WIND THREAT.
HIGHS WILL CLIMB BACK INTO THE MID 70S IN MOST AREAS...PARTICULARLY
IN THE WEST BEHIND THE CLEARING BUT AHEAD OF THE FRONT.
THE COLD FRONT WILL SWEEP ACROSS THE AREA BY EARLY EVENING...LEADING
TO COLD ADVECTION FOR MOST OF THE OVERNIGHT PERIOD AND LOWS DROPPING
INTO THE 40S FOR MOST OF CENTRAL NC.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 100 PM THURSDAY...
AVIATION CONDITIONS WILL BE MOSTLY ADVERSE FOR THE REST OF THE
AFTERNOON. WHILE THE HEAVIEST AND MOST WIDESPREAD RAIN (AND ISOLATED
STORMS) HAS MOVED EAST OF THE CENTRAL NC TERMINALS... THE SURFACE
COLD FRONT IS STILL ALIGNED ALONG THE MOUNTAINS OF WRN NC... AND THE
COMBINATION OF MOIST LOW LEVEL AIR AND GENERALLY LIGHT SURFACE WINDS
AHEAD OF THE FRONT WILL CONTINUE TO BRING PERIODS OF MVFR TO IFR
CIGS FOR THE NEXT FEW HOURS... ALTHOUGH PERIODS OF VFR CONDITIONS
MAY MIX IN FROM TIME TO TIME. CIGS ARE LIKELY TO REBOUND TO
PREDOMINANTLY VFR AT INT/GSO AFTER ABOUT 21Z OR 22Z... ALTHOUGH THE
THREAT OF MVFR/IFR CIGS WILL NOT SIGNIFICANTLY DIMINISH UNTIL AFTER
23Z AT RDU AND AFTER 02Z AT RWI/FAY... WITH PASSAGE OF THE COLD
FRONT. AFTER THIS TIME... WINDS WILL SHIFT AROUND TO MAINLY FROM THE
NW THEN FROM THE NORTH OVERNIGHT... AT SPEEDS UNDER 10 KTS. VFR
CONDITIONS ARE LIKELY FROM LATER TONIGHT THROUGH THE END OF THE
FORECAST PERIOD (18Z FRI) AS HIGH PRESSURE BUILDS IN.
LOOKING BEYOND 18Z FRI... HIGH PRESSURE RULES THROUGH SAT... LEADING
TO VFR CONDITIONS AND FAIRLY LIGHT WINDS. PASSAGE OF A MOSTLY DRY
COLD FRONT LATE SAT NIGHT MAY BRING BRIEF MVFR CIGS. ANOTHER COOL
HIGH PRESSURE AREA WILL THEN BUILD IN SUN THROUGH TUE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...HARTFIELD/22
SHORT TERM...26
LONG TERM...26
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
955 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA THIS
AFTERNOON AND EVENING. HIGH PRESSURE WILL BUILD OVER THE REGION ON
FRIDAY. A MAINLY DRY COLD FRONT WILL SWEEP ACROSS THE REGION
SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 AM THURSDAY...
WIDESPREAD MODERATE SHOWERS WITH EMBEDDED STORMS PERSIST OVER THE
ERN CWA. PONDING OF WATER ON STREETS AND OTHER FLOODING OF URBAN AND
LOW LYING AREAS HAS BEEN COMMON WITH RAINFALL RATES UP TO 1-2" PER
HOUR. INSTABILITY THUS FAR HAS BEEN MEAGER... ALTHOUGH MUCAPE VALUES
OF 100-250 J/KG (WHICH APPEARS TO BE MOSTLY RESTRICTED TO THE MID
AND HIGH LEVELS) COMBINED WITH STRONG FOCUSED UPPER DIVERGENCE HAS
BEEN SUFFICIENT FOR NUMEROUS LIGHTNING FLASHES (MOSTLY POSITIVE
STRIKES) WITHIN THE HEAVIER SHOWERS. LOW LEVEL SHEAR OF 30-40 KTS
HERE WITH 0-1 SRH VALUES OVER 300 M2/S2 WARRANTS CLOSE MONITORING
FOR ANY ENHANCED WIND SIGNATURES OR WEAK ROTATION OVER OUR SE OVER
THE NEXT FEW HOURS. OTHERWISE... WINDS ALOFT WILL SLOWLY VEER TO
MORE SW AS THE 850-700 MB TROUGH AXES ROTATE NE THROUGH ERN NC...
AND AS THE VERY HIGH PW AND LOW LEVEL MOISTURE TRANSPORT TRANSLATE
SLOWLY NORTHEASTWARD INTO THE AFTERNOON... RAINFALL WILL SLOWLY
TAPER DOWN FROM WEST TO EAST. WATER VAPOR IMAGERY SHOWS A VERY
PRONOUNCED BACK EDGE TO THE DEEPER MOISTURE BUT WITH A STEERING FLOW
HOLDING ROUGHLY PARALLEL TO THE SURFACE FRONTAL ZONE (WHICH IS
ANALYZED OVER FAR WRN NC) AND ANOTHER MID LEVEL VORTICITY LOBE STILL
TO COME THROUGH THIS AFTERNOON... IT WILL TAKE UNTIL LATER TODAY FOR
THE SURFACE FRONTAL ZONE TO BE PROPELLED NORTHEASTWARD THROUGH
CENTRAL NC. LOW LEVEL MOISTURE SHOULD HOLD OVER MUCH OF CENTRAL NC
BEHIND THE MAIN RAIN SHIELD WITH A DELAY IN DOWNSLOPE LOW LEVEL
FLOW... WHICH WILL KEEP A CHANCE OF SHALLOW SHOWERS AREAWIDE THROUGH
MUCH OF THE AFTERNOON... ALONG WITH A BRIEF FOG THREAT WHERE SURFACE
WINDS EAST OF THE MOUNTAINS BECOME LIGHT AND VARIABLE FOR A TIME
AHEAD OF THE FRONT. EXPECT HIGHS FROM AROUND 70 TO THE MID 70S... IN
LINE WITH HI-RES RAPID UPDATE GUIDANCE. -GIH
PREVIOUS DISCUSSION AS OF 410 AM THURSDAY: A LARGE AREA OF RAIN...
WITH A FEW EMBEDDED CONVECTIVE ELEMENTS...IS CURRENTLY TRANSLATING
EAST ACROSS THE FORECAST AREA AS A 50KT PREFRONTAL LOW-LEVEL JET
LIFTS NORTH TOWARD THE MID-ATLANTIC STATES 9PER REGIONAL VWP). THE
CONVECTIVE ELEMENTS LACK ANY LIGHTNING OR STRONG WIND SIGNATURES...
AND GIVEN THE LACK OF ANALYZED INSTABILITY NORTH OF THE SAVANNAH
RIVER BASIN...WE MAY BE FREE OF THUNDERSTORMS FOR THE EARLY MORNING
HOURS. LATER THIS MORNING...VEERING SURFACE WINDS AHEAD OF THE MAIN
COLD FRONT...WHICH IS CURRENTLY MOVING THROUGH NORTHERN GEORGIA AND
EASTERN TN/KY...SHOULD TAP INTO NEAR 70 DEWPOINT AIR OVER EAST-
CENTRAL SC AND LEAD TO SOME WEAK DESTABILIZATION (250-500 J/KG
MLCAPE) FROM THE SANDHILLS INTO THE COASTAL PLAIN BY MIDDAY. THERE
IS NO REAL CONSENSUS IN NEAR TERM GUIDANCE REGARDING THE COVERAGE OF
ADDITIONAL SHOWERS AND STORMS...SOME SHOW A BROKEN LINE AND SOME
SHOW JUST SCATTERED CONVECTION. THE BACK EDGE TO THE DEEP MOISTURE
IS RAPIDLY PUSHING EAST ACROSS THE MOUNTAINS AND IS OUTPACING THE
COLD FRONT....SO DEEP MOISTURE WILL BE LACKING BY THE TIME THE FRONT
ARRIVES. HOWEVER...THE RAP SHOWS A PRE-FRONTAL TROUGH THAT MAY
PROVIDE A FOCUS FOR SOME SCATTERED CONVECTION...MAINLY US 1 AND EAST
BY MIDDAY...AND A FEW ADDITIONAL SHOWERS EVEN POSSIBLE WITH THE
PRIMARY COLD FRONT LATER THIS AFTERNOON AND EVENING. IF SOME
MODERATELY DEEP CONVECTION CAN INITIATE TODAY...0-6KM BULK SHEAR
VALUES OF 35-45KT WOULD CERTAINLY SUPPORT A DAMAGING WIND THREAT.
HIGHS WILL CLIMB BACK INTO THE MID 70S IN MOST AREAS...PARTICULARLY
IN THE WEST BEHIND THE CLEARING BUT AHEAD OF THE FRONT.
THE COLD FRONT WILL SWEEP ACROSS THE AREA BY EARLY EVENING...LEADING
TO COLD ADVECTION FOR MOST OF THE OVERNIGHT PERIOD AND LOWS DROPPING
INTO THE 40S FOR MOST OF CENTRAL NC.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 650 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD THIS MORNING..WITH AN AREA OF HEAVY RAIN AND A FEW ISOLATED
STORMS BETWEEN ROUGHLY KVUJ AND KFAY MOVING NORTHEAST. MANY
TERMINALS...INCLUDING KRDU AND KRWI...CAN EXPECT LIMITED
VSBYS/CEILINGS AND BRIEF WIND GUSTS OF 20-30KT IN THIS HEAVY RAIN.
ALL OF THIS ACTIVITY SHOULD MOVE EAST OF KRWI BY 16Z...WITH A LOW
END CHANCE OF ADDITIONAL SHOWERS OR STORMS THIS AFTERNOON.
CONFIDENCE IN THIS REDEVELOPMENT IS TOO LOW FOR THE TAF RIGHT NOW. A
COLD FRONT TO THE WEST WILL MOVE ACROSS THE AREA THIS AFTERNOON AND
EVENING...WITH A SOUTH TO NORTHWEST WIND SHIFT BETWEEN 18Z AND 00Z.
IF THE FRONT IS SLOWER THAN EXPECTED...SOME BRIEF FOG MAY BE
POSSIBLE AT KFAY AND KRWI. .
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...HARTFIELD/22
SHORT TERM...26
LONG TERM...26
AVIATION...77/22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
650 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA THIS
AFTERNOON AND EVENING...FOLLOWED BY HIGH PRESSURE BUILDING OVER THE
REGION ON FRIDAY. A MOISTURE STARVED COLD FRONT WILL SWEEP
ACROSS THE REGION SATURDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 410 AM THURSDAY...
A LARGE AREA OF RAIN... WITH A FEW EMBEDDED CONVECTIVE ELEMENTS...IS
CURRENTLY TRANSLATING EAST ACROSS THE FORECAST AREA AS A 50KT
PREFRONTAL LOW-LEVEL JET LIFTS NORTH TOWARD THE MID-ATLANTIC STATES
9PER REGIONAL VWP). THE CONVECTIVE ELEMENTS LACK ANY LIGHTNING OR
STRONG WIND SIGNATURES...AND GIVEN THE LACK OF ANALYZED INSTABILITY
NORTH OF THE SAVANNAH RIVER BASIN...WE MAY BE FREE OF THUNDERSTORMS
FOR THE EARLY MORNING HOURS. LATER THIS MORNING...VEERING SURFACE
WINDS AHEAD OF THE MAIN COLD FRONT...WHICH IS CURRENTLY MOVING
THROUGH NORTHERN GEORGIA AND EASTERN TN/KY...SHOULD TAP INTO NEAR 70
DEWPOINT AIR OVER EAST-CENTRAL SC AND LEAD TO SOME WEAK
DESTABILIZATION (250-500 J/KG MLCAPE) FROM THE SANDHILLS INTO THE
COASTAL PLAIN BY MIDDAY. THERE IS NO REAL CONSENSUS IN NEAR TERM
GUIDANCE REGARDING THE COVERAGE OF ADDITIONAL SHOWERS AND
STORMS...SOME SHOW A BROKEN LINE AND SOME SHOW JUST SCATTERED
CONVECTION. THE BACK EDGE TO THE DEEP MOISTURE IS RAPIDLY
PUSHING EAST ACROSS THE MOUNTAINS AND IS OUTPACING THE COLD
FRONT....SO DEEP MOISTURE WILL BE LACKING BY THE TIME THE FRONT
ARRIVES. HOWEVER...THE RAP SHOWS A PRE-FRONTAL TROUGH THAT MAY
PROVIDE A FOCUS FOR SOME SCATTERED CONVECTION...MAINLY US 1 AND EAST
BY MIDDAY...AND A FEW ADDITIONAL SHOWERS EVEN POSSIBLE WITH THE
PRIMARY COLD FRONT LATER THIS AFTERNOON AND EVENING. IF SOME
MODERATELY DEEP CONVECTION CAN INITIATE TODAY...0-6KM BULK SHEAR
VALUES OF 35-45KT WOULD CERTAINLY SUPPORT A DAMAGING WIND THREAT.
HIGHS WILL CLIMB BACK INTO THE MID 70S IN MOST AREAS...PARTICULARLY
IN THE WEST BEHIND THE CLEARING BUT AHEAD OF THE FRONT.
THE COLD FRONT WILL SWEEP ACROSS THE AREA BY EARLY EVENING...LEADING
TO COLD ADVECTION FOR MOST OF THE OVERNIGHT PERIOD AND LOWS DROPPING
INTO THE 40S FOR MOST OF CENTRAL NC.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 650 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD THIS MORNING..WITH AN AREA OF HEAVY RAIN AND A FEW ISOLATED
STORMS BETWEEN ROUGHLY KVUJ AND KFAY MOVING NORTHEAST. MANY
TERMINALS...INCLUDING KRDU AND KRWI...CAN EXPECT LIMITED
VSBYS/CEILINGS AND BRIEF WIND GUSTS OF 20-30KT IN THIS HEAVY RAIN.
ALLA OF THIS ACTIVITY SHOULD MOVE EAST OF KRWI BY 16Z...WITH A LOW
END CHANCE OF ADDITIONAL SHOWERS OR STORMS THIS AFTERNOON.
CONFIDENCE IN THIS REDEVELOPMENT IS TOO LOW FOR THE TAF RIGHT NOW. A
COLD FRONT TO THE WEST WILL MOVE ACROSS THE AREA THIS AFTERNOON AND
EVENING...WITH A SOUTH TO NORTHWEST WIND SHIFT BETWEEN 18Z AND 00Z.
IF THE FRONT IS SLOWER THAN EXPECTED...SOME BRIEF FOG MAY BE
POSSIBLE AT KFAY AND KRWI. .
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...26
LONG TERM...26
AVIATION...77/22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
410 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA THIS
AFTERNOON AND EVENING...FOLLOWED BY HIGH PRESSURE BUILDING OVER THE
REGION ON FRIDAY. A MOISTURE STARVED COLD FRONT WILL SWEEP
ACROSS THE REGION SATURDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 410 AM THURSDAY...
A LARGE AREA OF RAIN... WITH A FEW EMBEDDED CONVECTIVE ELEMENTS...IS
CURRENTLY TRANSLATING EAST ACROSS THE FORECAST AREA AS A 50KT
PREFRONTAL LOW-LEVEL JET LIFTS NORTH TOWARD THE MID-ATLANTIC STATES
9PER REGIONAL VWP). THE CONVECTIVE ELEMENTS LACK ANY LIGHTNING OR
STRONG WIND SIGNATURES...AND GIVEN THE LACK OF ANALYZED INSTABILITY
NORTH OF THE SAVANNAH RIVER BASIN...WE MAY BE FREE OF THUNDERSTORMS
FOR THE EARLY MORNING HOURS. LATER THIS MORNING...VEERING SURFACE
WINDS AHEAD OF THE MAIN COLD FRONT...WHICH IS CURRENTLY MOVING
THROUGH NORTHERN GEORGIA AND EASTERN TN/KY...SHOULD TAP INTO NEAR 70
DEWPOINT AIR OVER EAST-CENTRAL SC AND LEAD TO SOME WEAK
DESTABILIZATION (250-500 J/KG MLCAPE) FROM THE SANDHILLS INTO THE
COASTAL PLAIN BY MIDDAY. THERE IS NO REAL CONSENSUS IN NEAR TERM
GUIDANCE REGARDING THE COVERAGE OF ADDITIONAL SHOWERS AND
STORMS...SOME SHOW A BROKEN LINE AND SOME SHOW JUST SCATTERED
CONVECTION. THE BACK EDGE TO THE DEEP MOISTURE IS RAPIDLY
PUSHINGEAST ACROSS THE MOUNTAINS AND IS OUTPACING THE COLD
FRONT....SO DEEP MISTURE WILL BE LACKING BY THE TIME THE FRONT
ARRIVES. HOWEVER...THE RAP SHOWS A PRE-FRONTAL TROUGH THAT MAY
PROVIDE A FOCUS FOR SOME SCATTERED CONVECTION...MAINLY US 1 AND EAST
BY MIDDAY...AND A FEW ADDITIONAL SHOWERS EVEN POSSIBLE WITH THE
PRIMARY COLD FRONT LATER THIS AFTERNOON AND EVENING. IF SOME
MODERATELY DEEP CONVECTION CAN INITIATE TODAY...0-6KM BULK SHEAR
VALUES OF 35-45KT WOULD CERTAINLY SUPPORT A DAMAGING WIND THREAT.
HIGHS WILL CLIMB BACK INTO THE MID 70S IN MOST AREAS...PARTICULARLY
IN THE WEST BEHIND THE CLEARING BUT AHEAD OF THE FRONT.
THE COLD FRONT WILL SWEEP ACROSS THE AREA BY EARLY EVENING...LEADING
TO COLD ADVECTION FOR MOST OF THE OVERNIGHT PERIOD AND LOWS DROPPING
INTO THE 40S FOR MOST OF CENTRAL NC.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 120 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD AS A FRONTAL SYSTEM BRINGS HEAVY RAIN AND GUSTY WINDS TO THE
AREA. A BAND OF SHOWERS IS CURRENTLY SHIFTING EASTWARD ACROSS
CENTRAL NC... ALONG WITH IFR/LOW END MVFR CONDITIONS. THE MAIN BAND
OF PRECIP SHOULD SHIFT TO THE EAST OF THE AREA BY AROUND 15Z OR SO.
HOWEVER... CIGS WILL CONTINUE TO REMAIN IN THE MVFR RANGE UNTIL THE
MAIN FRONT MOVES ACROSS THE AREA... ALONG WITH POSSIBLY SOME
LINGERING SHOWERS ACROSS THE EASTERN TAF SITES. IN ADDITION... A
BROKEN BAND OF SHOWERS AND ISOLATED STORMS MAY FORM ALONG/JUST IN
ADVANCE OF THE FRONT AS IT MOVES EASTWARD ACROSS THE AREA ON
THURSDAY AFTERNOON ACROSS THE EASTERN TAF SITES (MAINLY KRWI/KFAY).
IN ADDITION TO THE PRECIP...GUSTY WINDS CAN BE EXPECTED...WITH
SUSTAINED WIND SPEEDS OF 10-15 KTS GUSTING POSSIBLY AS HIGH AS 25
KTS BUT MORE LIKELY 15-20 KTS AT PERIODS UNTIL MID MORNING OR SO. AS
THE FRONT MOVES THROUGH A GIVEN LOCATION WIND WILL BECOME
NORTHWESTERLY... POSSIBLY BECOMING GUSTY FOR A BRIEF PERIOD AS WELL
(15-20 KT GUSTS).
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...26
LONG TERM...26
AVIATION...77/ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
400 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST
THIS EVENING...THEN TRACK EAST ACROSS THE CAROLINAS THURSDAY. HIGH
PRESSURE WILL BUILD INTO THE REGION FROM THE WEST ON FRIDAY. A
MAINLY DRY COLD FRONT WILL SWEEP ACROSS THE AREA SATURDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 1030 PM WEDNESDAY...
DEEP MID/UPPER LEVEL TROUGH CENTERED OVER THE CENTRAL PART OF THE
COUNTRY WILL CONTINUE TO SLOWLY SHIFT EASTWARD TONIGHT... WHILE THE
MAIN STACK LOW PRESSURE CENTER WILL CONTINUE TO LIFT NORTH-
NORTHEASTWARD OVERNIGHT INTO SOUTHERN CANADA. THE ASSOCIATED SURFACE
COLD FRONT WILL CONTINUE TO APPROACH THE AREA FROM THE WEST
OVERNIGHT... CURRENTLY EXTENDED SOUTHWARD FROM THE TN/KY INTO
EASTERN AL. THE FRONT SHOULD REMAIN TO THE WEST OF THE AREA
OVERNIGHT THOUGH. HOWEVER... A PREFRONTAL BAND OF SHOWERS AND EVEN
SOME ISOLATED THUNDERSTORMS WILL MOVE INTO THE AREA TONIGHT (MOVING
INTO WESTERN PORTIONS OF THE AREA NOW). THE BEST DYNAMICS WILL PASS
TO THE NORTH OF THE AREA AS THE MID LEVEL TROUGH DEAMPLIFIES AND
BROADENS. HOWEVER... WITH A GOOD SOUTHERLY LOW LEVEL FLOW AND STILL
GOOD MOISTURE TRANSPORT WE SHOULD SEE PW`S CLIMB TO AROUND 1.75" TO
2.0" OVERNIGHT. THUS... WE WILL SEE SOME MODERATE TO AT TIMES HEAVY
RAIN. HOWEVER... WITH FLASH FLOOD GUIDANCE GENERALLY ABOVE 2 INCHES
FOR ONE HOUR AND AROUND 2.5 TO 3 INCHES FOR 3 HOURS... THINK WE
SHOULD BE OK OUTSIDE OF POSSIBLY SOME MINOR FLOODING IN URBAN AREAS
(BEST CHANCES ACROSS THE TRIAD... WHERE WE COULD SEE RAINFALL
AMOUNTS OF AROUND 1 TO 1.5 INCHES). WITH REGARD TO A SEVERE
THREAT... THE LATEST RAP AND GFS CONTINUE TO SHOW WEAK INSTABILITY
INCREASING LATE TONIGHT WITH THE WAA... WITH UP TO 400-500 J/KG OF
MLCAPE BY AROUND 12Z ACROSS THE SOUTHWESTERN PIEDMONT AND SOUTHERN
SANDHILLS. THE LATEST DAY1 SPC CONVECTIVE OUTLOOK BRINGS THE
MARGINAL RISK VERY NEAR OUR SOUTHERN/SOUTHWESTERN COUNTIES. GIVEN
THE TIME OF DAY AND LACK OF ANY SEVERE WEATHER OVER THE LAST SEVERAL
HOURS... WOULD ANTICIPATE THIS THREAT TO BE QUITE SMALL... BUT NOT
ZERO GIVEN THE GOOD DEEP SHEAR (IF ENOUGH INSTABILITY ADVECTS
IN)...WITH THE MAIN THREAT FROM A VERY WEAK BRIEF TORNADO AND/OR
DAMAGING WIND GUST. TEMPS WILL GENERALLY REMAIN STEADY OVERNIGHT...
POSSIBLY EVEN INCREASING A DEGREE OR TWO ACROSS EASTERN PORTIONS OF
THE AREA... GENERALLY MID TO UPPER 60S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 345 AM THURSDAY...
BENEATH BRIEF HEIGHT RISES IN BROAD WSW FLOW ALOFT... CONTINENTAL
POLAR HIGH PRESSURE AND AN ASSOCIATED DEEPLY DRY AIR MASS WILL BUILD
EAST ACROSS THE TN VALLEY AND APPALACHIANS THROUGH FRI NIGHT. THE
RIDGE WILL BE SHORT-LIVED HOWEVER...AS A SHARP SHORTWAVE TROUGH AND
"ALBERTA CLIPPER" LOW AMPLIFY INTO THE CENTRAL PLAINS/MID MS VALLEY
REGION...THEN LIFT/TURN NORTHEASTWARD THROUGH THE GREAT LAKES SAT-
SAT NIGHT. AN ASSOCIATED TRAILING POLAR FRONT WILL MOVE EAST ACROSS
CENTRAL NC SAT NIGHT-EARLY SUNDAY. AT THE SAME TIME...THE MODELS TO
VARYING DEGREES INDICATE AN ACTIVE SOUTHERN STREAM JET WILL SUPPORT
A WAVE OR WAVES OF LOW PRESSURE ALONG A DEVELOPING/SHARPENING
COASTAL FRONT ALONG THE SOUTHEAST US COAST...RAISING THE STAKES FOR
SOME INTERACTION OF THE TWO AS THE POLAR FRONT COLLAPSES EAST AND
INTERCEPTS DEEPENING MOISTURE CENTERED ALONG THE COASTAL CAROLINAS.
WHILE THE GFS REMAINS DRY...WITH MORE LIMITED DEEP MOISTURE OVER
CENTRAL NC...THE CONSENSUS OF OTHER GUIDANCE INCLUDING THE LATEST
EC/NMM/SREF/GEM...ALL SUPPORT VERY LIGHT QPF OVER THE EASTERN
PIEDMONT/SANDHILLS/COASTAL PLAIN SAT NIGHT...AT WHICH TIME A SLIGHT
CHANCE OF SHOWERS HAVE ACCORDINGLY BEEN INTRODUCED GENERALLY EAST OF
US HIGHWAY 1.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 355 AM THURSDAY...
THE 00Z/19TH ECMWF IS AN AGGRESSIVE OUTLIER THAT HOLDS THE
ASSOCIATED MERGED FRONTAL ZONE JUST OFFSHORE THROUGH SUN
NIGHT...WITH AN AXIS OF A QUARTER TO HALF INCH OF QPF LINGERING AS
FAR WEST AS THE I-95 CORRIDOR DURING THAT TIME. WILL FOLLOW WPC/S
PREFERENCE TOWARD A MORE PROGRESSIVE FRONTAL DEPARTURE AND
INCREASINGLY INFLUENTIAL...AND RENEWED...CONTINENTAL POLAR RIDGING
FROM THE WEST FOR THE PERIOD SUNDAY THROUGH MID-WEEK. THE ASSOCIATED
COOLEST TEMPERATURES WILL OCCUR SUN-MON...WITH HIGHS MOSTLY IN THE
UPPER 40S TO LOW 50S...AND LOWS IN THE MID-UPPER 20S...AND WITH
MODERATION INTO THE 50S AND 30S...RESPECTIVELY...THROUGH THE END OF
THE PERIOD.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 120 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD AS A FRONTAL SYSTEM BRINGS HEAVY RAIN AND GUSTY WINDS TO THE
AREA. A BAND OF SHOWERS IS CURRENTLY SHIFTING EASTWARD ACROSS
CENTRAL NC... ALONG WITH IFR/LOW END MVFR CONDITIONS. THE MAIN BAND
OF PRECIP SHOULD SHIFT TO THE EAST OF THE AREA BY AROUND 15Z OR SO.
HOWEVER... CIGS WILL CONTINUE TO REMAIN IN THE MVFR RANGE UNTIL THE
MAIN FRONT MOVES ACROSS THE AREA... ALONG WITH POSSIBLY SOME
LINGERING SHOWERS ACROSS THE EASTERN TAF SITES. IN ADDITION... A
BROKEN BAND OF SHOWERS AND ISOLATED STORMS MAY FORM ALONG/JUST IN
ADVANCE OF THE FRONT AS IT MOVES EASTWARD ACROSS THE AREA ON
THURSDAY AFTERNOON ACROSS THE EASTERN TAF SITES (MAINLY KRWI/KFAY).
IN ADDITION TO THE PRECIP...GUSTY WINDS CAN BE EXPECTED...WITH
SUSTAINED WIND SPEEDS OF 10-15 KTS GUSTING POSSIBLY AS HIGH AS 25
KTS BUT MORE LIKELY 15-20 KTS AT PERIODS UNTIL MID MORNING OR SO. AS
THE FRONT MOVES THROUGH A GIVEN LOCATION WIND WILL BECOME
NORTHWESTERLY... POSSIBLY BECOMING GUSTY FOR A BRIEF PERIOD AS WELL
(15-20 KT GUSTS).
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...77
SHORT TERM...26
LONG TERM...26
AVIATION...77/ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
120 AM EST THU NOV 19 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST
THIS EVENING...THEN TRACK EAST ACROSS THE CAROLINAS THURSDAY. HIGH
PRESSURE WILL BUILD INTO THE REGION FROM THE WEST ON FRIDAY. A
MAINLY DRY COLD FRONT WILL SWEEP ACROSS THE AREA SATURDAY NIGHT.
&&
.NEAR TERM /TONIGHT/...
AS OF 1030 PM WEDNESDAY...
DEEP MID/UPPER LEVEL TROUGH CENTERED OVER THE CENTRAL PART OF THE
COUNTRY WILL CONTINUE TO SLOWLY SHIFT EASTWARD TONIGHT... WHILE THE
MAIN STACK LOW PRESSURE CENTER WILL CONTINUE TO LIFT NORTH-
NORTHEASTWARD OVERNIGHT INTO SOUTHERN CANADA. THE ASSOCIATED SURFACE
COLD FRONT WILL CONTINUE TO APPROACH THE AREA FROM THE WEST
OVERNIGHT... CURRENTLY EXTENDED SOUTHWARD FROM THE TN/KY INTO
EASTERN AL. THE FRONT SHOULD REMAIN TO THE WEST OF THE AREA
OVERNIGHT THOUGH. HOWEVER... A PREFRONTAL BAND OF SHOWERS AND EVEN
SOME ISOLATED THUNDERSTORMS WILL MOVE INTO THE AREA TONIGHT (MOVING
INTO WESTERN PORTIONS OF THE AREA NOW). THE BEST DYNAMICS WILL PASS
TO THE NORTH OF THE AREA AS THE MID LEVEL TROUGH DEAMPLIFIES AND
BROADENS. HOWEVER... WITH A GOOD SOUTHERLY LOW LEVEL FLOW AND STILL
GOOD MOISTURE TRANSPORT WE SHOULD SEE PW`S CLIMB TO AROUND 1.75" TO
2.0" OVERNIGHT. THUS... WE WILL SEE SOME MODERATE TO AT TIMES HEAVY
RAIN. HOWEVER... WITH FLASH FLOOD GUIDANCE GENERALLY ABOVE 2 INCHES
FOR ONE HOUR AND AROUND 2.5 TO 3 INCHES FOR 3 HOURS... THINK WE
SHOULD BE OK OUTSIDE OF POSSIBLY SOME MINOR FLOODING IN URBAN AREAS
(BEST CHANCES ACROSS THE TRIAD... WHERE WE COULD SEE RAINFALL
AMOUNTS OF AROUND 1 TO 1.5 INCHES). WITH REGARD TO A SEVERE
THREAT... THE LATEST RAP AND GFS CONTINUE TO SHOW WEAK INSTABILITY
INCREASING LATE TONIGHT WITH THE WAA... WITH UP TO 400-500 J/KG OF
MLCAPE BY AROUND 12Z ACROSS THE SOUTHWESTERN PIEDMONT AND SOUTHERN
SANDHILLS. THE LATEST DAY1 SPC CONVECTIVE OUTLOOK BRINGS THE
MARGINAL RISK VERY NEAR OUR SOUTHERN/SOUTHWESTERN COUNTIES. GIVEN
THE TIME OF DAY AND LACK OF ANY SEVERE WEATHER OVER THE LAST SEVERAL
HOURS... WOULD ANTICIPATE THIS THREAT TO BE QUITE SMALL... BUT NOT
ZERO GIVEN THE GOOD DEEP SHEAR (IF ENOUGH INSTABILITY ADVECTS
IN)...WITH THE MAIN THREAT FROM A VERY WEAK BRIEF TORNADO AND/OR
DAMAGING WIND GUST. TEMPS WILL GENERALLY REMAIN STEADY OVERNIGHT...
POSSIBLY EVEN INCREASING A DEGREE OR TWO ACROSS EASTERN PORTIONS OF
THE AREA... GENERALLY MID TO UPPER 60S.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 320 PM WEDNESDAY...
MODEL GUIDANCE REMAINS CONSISTENT AND IN FAIRLY GOOD AGREEMENT ON
THE TIMING OF THE COLD FRONT THROUGH CENTRAL NC BETWEEN MID MORNING
AND EARLY EVENING THU (ALTHOUGH THE CHILLIER AND MUCH DRIER AIR WILL
TAKE AWHILE LONGER TO SCALE THE MOUNTAINS). THE STEADY SHOWERS WILL
CROSS THE AREA A FEW HOURS AHEAD OF THE FRONT... FROM THE EARLY
MORNING PREDAWN HOURS THROUGH MID TO LATE AFTERNOON. ONCE AGAIN AN
ISOLATED STORM OR TWO IS POSSIBLE... PARTICULARLY EAST OF HIGHWAY 1
WHERE SOME EARLY-DAY HEATING AND SLIGHTLY HIGHER SURFACE DEWPOINTS
SHOULD PUSH UP THE RISK OF A FEW HUNDRED J/KG OF CAPE BY THE TIME
THE MAIN RAIN SHIELD ARRIVES... SO WILL GO WITH A SLIGHTLY HIGHER
THUNDER RISK IN THE FAR EAST. BY THIS TIME THE LOW-MID LEVEL WINDS
WILL BE FROM THE SW... FAVORING A LINEAR STRUCTURE TO ANY
CONVECTION... SO A FEW WEAK BOWING SEGMENTS WITH ENHANCED WIND GUSTS
CANNOT BE RULED OUT... BUT THE DECREASING BACKGROUND WINDS AND LOW
LEVEL SHEAR MAGNITUDES WILL LIMIT THE THREAT OF ANY VERY STRONG
WINDS. RAINFALL INTENSITY IS EXPECTED TO DECREASE A BIT AS THE BAND
SHIFTS OUT OF THE MOUNTAINS AND INTO THE PIEDMONT... A FUNCTION OF
THE DROPOFF IN LARGE SCALE LIFT... SO AMOUNTS ARE NOT EXPECTED TO
POSE A FLOODING THREAT. BUT GIVEN THE VIGOROUS LOW LEVEL MOISTURE
TRANSPORT... WE SHOULD STILL EXPECT STORM TOTAL AMOUNTS OF AROUND
1.0-1.5" WHICH MAY LEAD TO MINOR FLOODING IN URBAN AND LOW LYING
AREAS. PRECIP SHOULD BE TAPERING OFF DURING THE MID-LATE
AFTERNOON... WITH POPS GENERALLY ENDING BY 01Z AND CLEARING SKIES
FROM MID EVENING THROUGH THE NIGHT AS THE COLUMN DRIES AND
STABILIZES. HIGHS SHOULD REACH 72-78. LOWS 43-50. -GIH
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 225 PM WEDNESDAY...
FOR THE PERIOD FRIDAY THROUGH SATURDAY...A DRY AIR MASS BUILDS INTO
CENTRAL NORTH CAROLINA WITH AN 850MB THETA-E TROUGH...NEGATIVE K
INDICES...AND PRECIPITABLE WATER VALUES AT OR BELOW A HALF-INCH.
STRONGER UPPER-LEVEL WINDS ARE FORECAST NORTH OF CENTRAL NORTH
CAROLINA...AND WHERE THE GUIDANCE FORECASTS SOME UPPER-LEVEL
MOISTURE THIS RESIDES MAINLY NORTH OF CENTRAL NORTH CAROLINA IN
VICINITY OF THOSE HIGHER WINDS ALOFT. BUFR SOUNDINGS FROM BOTH THE
NAM AND GFS ARE DRY...EVEN AS A WEAK MID-LEVEL WAVE OR TWO MOVES
THROUGH THE AREA IN THE SOUTHWEST FLOW ALOFT.
925MB WINDS ARE NEARLY 30KT AT 12Z FRIDAY IN THE TIGHT GRADIENT
BEHIND THE FRONT...AS HIGH PRESSURE BUILDS EAST. EXPECT SOME BREEZY
CONDITIONS FOR A PART OF FRIDAY WITH MIXING...AND SOME WIND GUSTS
COULD BE BRIEFLY 25 TO 30 MPH PARTICULARLY IN THE INTERSTATE 95
CORRIDOR. THE GRADIENT RELAXES SOME BY FRIDAY NIGHT ALTHOUGH THERE
APPEARS TO BE ENOUGH GRADIENT FOR A LIGHT BUT NOTICEABLE WIND FOR
MUCH OF NIGHT ESPECIALLY EAST OF U.S. 1. THERE SHOULD BE SOME LESSER
GUSTS IN THE TEENS KNOTS EARLY SATURDAY WITH MIXING ACCORDING TO THE
BUFR SOUNDINGS BEFORE WINDS GRADUALLY DIMINISH...WITH POSSIBLY A
LATE-DAY GUST IN THE LOWER TEENS MPH NEAR THE TRIAD AS WINDS BECOME
SOUTHWEST. HIGHS ANTICIPATED FROM 1000-850MB THICKNESSES CORRESPOND
WELL TO THE CONSENSUS OF MAV AND GRIDDED MOS GUIDANCE...THE FORMER
WHICH HAS BEEN DIFFICULT TO BEAT OF LATE...FOR HIGHS IN THE UPPER
50S TO MID 60S FRIDAY AND MAINLY 55 TO 60 SATURDAY AS THICKNESSES
ARE JUST A FEW METERS LOWER THEN. OVERNIGHT LOWS FRIDAY NIGHT IN THE
30S.
FOR THE PERIOD SATURDAY NIGHT THROUGH WEDNESDAY...A SOUTHWEST FLOW
ALOFT CONTINUES EARLY IN THIS PART OF THE LONG-TERM PERIOD WITH A
MID-LEVEL TROUGH APPROACHING AND MOVING THROUGH CENTRAL NORTH
CAROLINA EARLY IN THE NEXT WORK WEEK. AHEAD OF THE TROUGH THE LONG-
TERM GUIDANCE DEVELOPS A WAVE ALONG AND JUST AHEAD OF A FRONTAL
BOUNDARY THAT PASSES THROUGH CENTRAL NORTH CAROLINA SATURDAY NIGHT
INTO SUNDAY...WHILE KEEPING THE SURFACE LOW PRESSURE AND MOST OF ITS
MOISTURE OFFSHORE. THE GFS REMAINS DRY WITH THE FRONTAL
PASSAGE...WHILE THE 12Z ECMWF HAS TRENDED WETTER WITH THE
FRONT...THE FORMER SHOWING STRONGER SURFACE RIDGING AHEAD OF THE
FRONT WHILE THE LATTER WEAKENS THE HIGH MORE WITH A SHARPER TROUGH.
IN ADDITION...BOTH THE GFS AND THE ECWMF TRY TO PROVIDE FOR VERY
MARGINAL QPF...BARELY MEASURABLE...QPF JUST EAST OF CENTRAL NORTH
CAROLINA POST-FRONTAL CLOSER TO LOW PRESSURE OFFSHORE. GIVEN THE DRY
AIR IN PLACE...UNCERTAINTY REGARDING THE ABILITY OF LOW PRESSURE TO
PUSH MOISTURE BACK INTO CENTRAL NORTH CAROLINA...AND THE LOW QPF
WHERE IT DOES EXIST...WILL KEEP PRECIPITATION CHANCES BELOW SLIGHT
FOR NOW AND MONITOR THE LONG-TERM GUIDANCE TRENDS FOR POSSIBLE
ADDITION OF LOW CHANCES ESPECIALLY WITH THE FRONT OVERNIGHT
SATURDAY.
AN UPPER RIDGE BUILDS IN LATE IN THE LONG-TERM PERIOD WHICH SHOULD
HELP TO MODERATE THE AIR MASS. COLDEST TEMPERATURES SHOULD BE SUNDAY
AND SUNDAY NIGHT WITH HIGHS SUNDAY STAYING IN...OR STRUGGLING TO GET
OUT OF...THE 40S AND OVERNIGHT LOWS SUNDAY NIGHT SOLIDLY IN THE 20S
ALMOST AREAWIDE. IT COULD ALSO BE MODESTLY BREEZY WITH MIXING SUNDAY
IN A GRADIENT BETWEEN HIGH PRESSURE TRYING TO BUILD IN AND LOW
PRESSURE OFFSHORE...ADDING A LITTLE TO THE CHILL.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 120 AM THURSDAY...
24 HOUR TAF PERIOD: HIGH CONFIDENCE OF ADVERSE CONDITIONS IN THE TAF
PERIOD AS A FRONTAL SYSTEM BRINGS HEAVY RAIN AND GUSTY WINDS TO THE
AREA. A BAND OF SHOWERS IS CURRENTLY SHIFTING EASTWARD ACROSS
CENTRAL NC... ALONG WITH IFR/LOW END MVFR CONDITIONS. THE MAIN BAND
OF PRECIP SHOULD SHIFT TO THE EAST OF THE AREA BY AROUND 15Z OR SO.
HOWEVER... CIGS WILL CONTINUE TO REMAIN IN THE MVFR RANGE UNTIL THE
MAIN FRONT MOVES ACROSS THE AREA... ALONG WITH POSSIBLY SOME
LINGERING SHOWERS ACROSS THE EASTERN TAF SITES. IN ADDITION... A
BROKEN BAND OF SHOWERS AND ISOLATED STORMS MAY FORM ALONG/JUST IN
ADVANCE OF THE FRONT AS IT MOVES EASTWARD ACROSS THE AREA ON
THURSDAY AFTERNOON ACROSS THE EASTERN TAF SITES (MAINLY KRWI/KFAY).
IN ADDITION TO THE PRECIP...GUSTY WINDS CAN BE EXPECTED...WITH
SUSTAINED WIND SPEEDS OF 10-15 KTS GUSTING POSSIBLY AS HIGH AS 25
KTS BUT MORE LIKELY 15-20 KTS AT PERIODS UNTIL MID MORNING OR SO. AS
THE FRONT MOVES THROUGH A GIVEN LOCATION WIND WILL BECOME
NORTHWESTERLY... POSSIBLY BECOMING GUSTY FOR A BRIEF PERIOD AS WELL
(15-20 KT GUSTS).
OUTLOOK: EXPECT A RETURN TO VFR CONDITIONS WITH A VERY SLIGHT CHANCE
OF PRECIPITATION WITH A FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING
BUT OTHERWISE DRY CONDITIONS SHOULD PREVAIL.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...77
SHORT TERM...HARTFIELD
LONG TERM...DJF
AVIATION...77/ELLIS
AREA FORECAST DISCUSSION
NWS PORTLAND OR
944 AM PST THU NOV 19 2015
.SYNOPSIS...LOW PRES ON THE N OREGON COAST THIS MORNING WILL
CONTINUE TO MOVE SE TODAY...INTO EASTERN OREGON THIS AFTERNOON. FLOW
WILL TURN OFFSHORE FRIDAY INTO THE UPCOMING WEEKEND AS COOL HIGH
PRESSURE SETTLES INTO THE INTERIOR PAC NW. THIS WILL LEAD TO A
PERIOD OF DRY BUT COOL WEATHER OVER THE WEEKEND. A COLD FRONT FROM
THE GULF OF ALASKA IS EXPECTED TO BRING THE NEXT CHANCE OF RAIN AND
MOUNTAIN SNOW MONDAY...WITH SHARPLY COLDER WEATHER SETTLING IN FOR
MUCH OF NEXT WEEK.
&&
.SHORT TERM...SURFACE ANALYSIS SHOWED A LOW PRES CENTER AROUND 1015
MB THIS MORNING NEARING THE COAST AROUND KTMK...PRETTY WELL ON TRACK
WITH PREVIOUS MODEL EXPECTATIONS. THE LOW IS EXPECTED TO CONTINUE TO
SLIDE OFF TO THE ESE TODAY...MOVING INTO EASTERN OREGON THIS
AFTERNOON. WITH AN OFFSHORE FLOW THROUGH THE GORGE TO THE N OF THE
EXPECTED LOW TRACK SNOW LEVELS HAD DIPPED DOWN AS LOW 1500 FT AROUND
PARKDALE....SO WILL NEED TO MENTION SOME LIGHT SNOW IN THE UPPER
GOOD RIVER VALLEY THIS MORNING UNTIL FLOW TURNS BACK ONSHORE ONCE
THE LOW MOVES E OF THE CASCADES. SNOW IN THE CASCADES THUS FAR HAS
GENERALLY BEEN ON THE LOW END OF ADVISORY...AND WITH TEMPS ON MT
HOOD NOW UP TO FREEZING AT TIMEBERLINE LODGE EXPECT MAIN SNOW
ACCUMULATION PERIOD IS OVER SO CAN DROP THE ADVISORY A LITTLE EARLY
FOR THE N OREGON CASCADES. IN THE S WA CASCADES RADAR SHOWED
PRECIPITATION BECOMING MORE SHOWERY WITH PRECIPITATION RATES IN THE
PAST FEW HOURS ONLY ON TRACK TO GIVE A COUPLE MORE INCHES OF SNOW TO
THE HIGHER TERRAIN. RADAR SUGGESTS THE BACK EDGE OF MAIN
PRECIPITATION AREA OVER OREGON ALSO PROGRESSING QUICKLY E INTO THE
CASCADES THIS MORNING. HRRR CONTINUES TO SHOW THIS WELL...WITH
LITTLE IN THE WAY OF SHOWERS FOLLOWING ON THE BACK SIDE OF THE LOW
AS LOW LEVEL FLOW BEHIND THE COLD FRONT TURNS MORE NORTHERLY.
REMAINDER OF SHORT TERM DISCUSSION UNCHANGED...BY FRI MORNING OUR
CWA SHOULD BE UNDER THE INFLUENCE OF DRY NORTHERLY FLOW...WITH A
CHILLY START TO THE DAY AND POSSIBLY PATCHY VALLEY FOG.
COLD POOL HIGH PRESSURE IS EXPECTED TO STRENGTHEN EAST OF THE
CASCADES FRIDAY AND INTO THIS WEEKEND...YIELDING BRISK EAST WINDS
THROUGH THE GORGE. FUTURE SHIFTS MAY NEED TO LOOK AT INCREASING THE
EAST WINDS INTO THE PDX METRO AREA THIS WEEKEND AS LATEST NAM RUNS
HAVE BEEN SHOWING KTTD-KDLS GRADIENTS OF -5 TO -7 MB...WHICH COULD
PRODUCE GUSTS 50-70 MPH AT THE WINDIER LOCATIONS OF THE WEST GORGE
AND 30-40 MPH NEAR TROUTDALE. THIS SEEMS FAIRLY REASONABLE GIVEN THE
COLD POOL SETUP EXPECTED TO TAKE PLACE EAST OF THE CASCADES THE NEXT
FEW DAYS. THE OFFSHORE FLOW WILL BRING A BREAK IN PRECIPITATION...
WITH A DECENT AMOUNT OF SUNSHINE OUTSIDE OF PATCHY VALLEY FOG AWAY
FROM THE GORGE. WEAGLE
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS. SATURDAY NIGHT
THROUGH WEDNESDAY...MODELS CONTINUE TO ADVERTISE A PRETTY MAJOR
PATTERN CHANGE IN THE LATTER PART OF THE EXTENDED PERIOD. SAT NIGHT
AND SUN LOOK TO REMAIN DRY WITH SOME DEGREE OF OFFSHORE LOW-LEVEL
FLOW. THERMALLY-INDUCED SURFACE TROUGH RESIDES ALONG THE COAST SAT
NIGHT THEN WEAKENS SUN. SHOULD SEE A FAIRLY LARGE MIN TEMP RANGE SAT
NIGHT WITH SUBSIDENCE INVERSIONS IN THE HIGHER TERRAIN. THINGS START
TO GET INTERESTING MON AS AN UPPER TROUGH DIVES SOUTH FROM THE GULF
OF ALASKA. THE OPERATIONAL ECMWF AND GFS ARE SIMILAR IN THE OVERALL
LARGE-SCALE PATTERN. COLD FRONTAL BOUNDARY SLIDES SOUTH THROUGH
WASHINGTON MON WITH 1000-500 MB THICKNESS VALUES LOWERING TO NEAR
530 DM ACROSS SW WA AND FAR NW OREGON 00Z TUE. BOTH MODELS THEN SHOW
A RE-ENFORCING SHOT OF COLDER AIR DIGGING INTO THE UPPER TROUGH MON
NIGHT AND TUE. BY 00Z WED THE OPERATIONAL ECMWF HAS THICKNESS VALUES
IN THE LOW TO MID 520S AND 850 MB TEMPS AROUND -6C OVER SW WA AND
FAR NW OREGON. SHOULD THIS VERIFY...SNOW LEVELS WOULD BE DOWN TO AT
LEAST 1000 FT...IF NOT A LITTLE LOWER. THE COLD PATTERN HOLDS
THROUGH WED. THE ECMWF IS MUCH SLOWER PUSHING THE UPPER TROUGH SOUTH
COMPARED TO THE GFS. IN FACT...THE GFS SHOWS NELY FLOW ALOFT WED
WITH COLD AIR STACKING UP AGAINST THE S WA AND N OREGON CASCADES.
GFS HAS 850 MB TEMPS OF -10C TO -12C OVER THE S WA AND N OREGON
CASCADE CREST 18Z WED. STILL TOO EARLY TO TRY AND PIN DOWN THE FINER
DETAILS...BUT CONFIDENCE IS GROWING THAT WE MAY ENDURE A MUCH COLDER
AIR MASS THE FIRST PART OF NEXT WEEK. WEISHAAR.
&&
.AVIATION...DEPARTING WARM FRONT WILL KEEP MIXED FLIGHT CONDITIONS
TODAY AND TONIGHT. SHOWERS IMPACTING LOCATIONS EAST OF I-5...WILL
GRADUALLY TAPER OFF THIS AFTERNOON. CIGS REMAIN MOSTLY MVFR AND
IFR...WITH VIS SLIGHTLY IMPROVING TO HIGH-END MVFR/LOW-END VFR FOR
MOST SITES AFTER 21Z THU THEN DETERIORATING AGAIN THIS EVENING.
EXPECT IFR/LIFR FOG TO DEVELOP AFTER 04Z-06Z FRI.
KPDX AND APPROACHES...MVFR CIGS/VSBYS CONTINUE TODAY AND
TONIGHT...WITH RAIN TAPERING OFF NEXT FEW HOURS. SOME IMPROVEMENT
IN CIGS LIKELY AFTER 20Z THU. EAST WINDS REMAIN REMAIN 10 TO 20 KT
EARLY THIS MORNING...DECREASING BY AROUND MIDDAY. MVFR/IFR FOG OR
LOW STRATUS DEVELOPS AFTER 06Z-08Z FRI. /27
&&
.MARINE...SURFACE LOW PRESSURE CONTINUES TO APPROACH THE
COAST...PRESENTLY ENTERING THE COASTAL WATERS /OR 60 NM
OFFSHORE/ WEST OF CASCADE HEAD. SOLID SMALL CRAFT WINDS CONTINUE
OVER ALL WATERS...WITH EAST WINDS OVER THE NORTHERN WATERS NORTH
OF THE LOW AND SOUTH TO SOUTHEAST WINDS TO THE SOUTH. AS
EXPECTED...THE STRONGEST GUSTS HAVE BEEN TO THE SOUTH AND
IMMEDIATELY AHEAD OF THE LOW.
WINDS TURN MORE NORTHERLY ONCE THE LOW MOVES ONSHORE EARLY
THURSDAY...WITH ADVISORY LEVEL GUSTS CONTINUING INTO THIS EVENING.
THEN...OVERALL WEAKLY DEFINED SURFACE PATTERN FOR MORE BENIGN
CONDITIONS. A THERMAL LOW BUILDS UP THE COAST FRIDAY AND MAY
REMAIN ALONG THE COAST THROUGH THE WEEKEND FOR OFFSHORE FLOW.
SEAS SOUTH OF CASCADE HEAD WILL REMAIN 10 TO 11 FT THROUGH LATE THIS
MORNING AS THE LOW MOVES ACROSS...BUT WILL CONTINUE TO SUBSIDE
THIS AFTERNOON. SEAS OVER THE NORTHERN WATERS REMAIN 7 TO 9 FT
RANGE THROUGH FRIDAY. SEAS SOUTH WILL SUBSIDE TO LESS THAN 10 FT
BY THURSDAY EVENING. CULLEN/27
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 7 PM PST THIS EVENING FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 PM PST THIS
AFTERNOON FOR COASTAL WATERS FROM CASCADE HEAD OR TO
FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL NOON
PST TODAY.
&&
$$
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 PORTLAND OR
405 AM PST THU NOV 19 2015
.SYNOPSIS...LOW PRESSURE IS MOVING ONSHORE NEAR LINCOLN CITY THIS
MORNING...BRINGING GUSTY SOUTH WINDS TO THE CENTRAL COAST AND PLENTY
OF RAIN AND HIGH ELEVATION SNOW TO NORTHWEST OREGON AND SOUTHWEST
WASHINGTON. EXPECT RAIN TO TAPER TO SHOWERS AS THE LOW MOVES EAST OF
THE CASCADES AND HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. FLOW
WILL TURN OFFSHORE FRIDAY INTO THE UPCOMING WEEKEND AS COOL HIGH
PRESSURE SETTLES INTO THE INTERIOR PAC NW. THIS WILL LEAD TO A PERIOD
OF DRY BUT COOL WEATHER OVER THE WEEKEND. A COLD FRONT FROM THE GULF
OF ALASKA IS EXPECTED TO BRING THE NEXT CHANCE OF RAIN AND MOUNTAIN
SNOW MONDAY...WITH SHARPLY COLDER WEATHER SETTLING IN FOR MUCH OF
NEXT WEEK.
&&
.SHORT TERM...TODAY THROUGH SATURDAY...MSAS SURFACE ANALYSIS AND AREA
SURFACE OBSERVATIONS SHOW AN ELONGATED LOW PRESSURE CENTER MOVING
ONSHORE NEAR THE TILLAMOOK/LINCOLN COUNTY BORDER EARLY THIS MORNING.
TO THE SOUTH OF THIS...SOUTH WINDS HAVE INCREASED WITH GUSTS 40-45
MPH FAIRLY COMMON ALONG THE COAST. TO THE NORTH...WINDS HAVE REMAINED
MODERATE NORTHEASTERLY AND THUS WE DECIDED TO CANCEL THE HIGH WIND
WARNING FOR THE NORTH OREGON COAST AND COAST RANGE. DECIDED TO LET
THE HIGH WIND WARNING STAND FOR THE LANE/LINCOLN COUNTY COAST...BUT
IT MAY BE AN UPHILL BATTLE FOR IT TO VERIFY. SINCE THIS SYSTEM
APPEARS TO BE UNDERPERFORMING WIND-WISE...WE ALSO DECIDED TO CANCEL
THE WIND ADVISORY FOR THE CENTRAL AND SOUTHERN WILLAMETTE VALLEY. IT
APPEARS THE STRONGEST VALLEY GUSTS WILL BE PRIMARILY SOUTH OF ALBANY
AND INTO THE EUGENE AREA...BUT EVEN THERE IT WILL BE A STRUGGLE TO
GET GUSTS ABOVE 30 MPH PER MOST GUIDANCE AND LATEST TRENDS.
LOOKS LIKE IT WAS A GOOD CALL TO CANCEL THE FLOOD WATCH YESTERDAY AS
RAIN RATES HAVE NOT BEEN ALL THAT IMPRESSIVE. MOST OF THE FORECAST
AREA HAS SEEN STEADY LIGHT TO OCCASIONALLY MODERATE RAIN...WITH
RAINFALL TOTALS GENERALLY ON THE ORDER OF 0.50-1.00 INCH THUS FAR IN
NW OREGON AND LIGHTER AMOUNTS IN SW WASHINGTON. ANOTHER 0.50-1.00
INCH IS POSSIBLE MAINLY SOUTH OF SALEM...WHERE THE AXIS OF GREATEST
MOISTURE FLUX LIES. STORM TOTALS COULD REACH 1.50-3.00 INCHES IN THE
HIGHER TERRAIN SOUTH OF SALEM...PROBABLY NOT ENOUGH TO CAUSE MUCH IN
THE WAY OF HYDROLOGIC PROBLEMS.
SNOW LEVELS REMAIN IN THE 4500-5000 FT RANGE IN THE N OR/S WA
CASCADES...WITH WET SNOW SHOWING UP ON THE ODOT WEBCAM AT SANTIAM
PASS. SO FAR 3-6 INCHES OF SNOW HAVE FALLEN ABOVE 5000 FT FOR THE N
OR/S WA CASCADES...AND A FEW MORE INCHES ARE POSSIBLE BEFORE
PRECIPITATION TAPERS TO SHOWERS LATER THIS MORNING...ESPECIALLY MT
HOOD SOUTHWARD. WAS TEMPTED TO CANCEL THE SNOW ADVISORY FOR THE S WA
CASCADES AS RADAR TRENDS SEEM TO INDICATE PRECIP DWINDLING OVER THE
PAST COUPLE HOURS DUE TO THE SLIGHTLY MORE SOUTHERN TRACK OF THE LOW
VERSUS WHAT WAS EXPECTED. WILL KEEP AN EYE ON THIS THE NEXT COUPLE
HOURS...MAY SEND A QUICK UPDATE IF TO CANCEL THE ADVISORY FOR THE S
WA CASCADES IF THIS TREND CONTINUES.
LATEST FEW HRRR RUNS CONTINUE TO SHOW A FAIRLY SHARP BACK EDGE OF THE
PRECIP MOVING FROM NW TO SE LATER THIS MORNING THROUGH THIS EVENING.
THERE MAY EVEN BE A FEW SUNBREAKS FROM THE PORTLAND METRO
NORTHWESTWARD BY LATE AFTERNOON AS HIGH PRESSURE BEGINS TO BUILD IN
FROM THE NW. BY FRI MORNING OUR CWA SHOULD BE UNDER THE INFLUENCE OF
DRY NORTHERLY FLOW...WITH A CHILLY START TO THE DAY AND POSSIBLY
PATCHY VALLEY FOG.
COLD POOL HIGH PRESSURE IS EXPECTED TO STRENGTHEN EAST OF THE
CASCADES FRIDAY AND INTO THIS WEEKEND...YIELDING BRISK EAST WINDS
THROUGH THE GORGE. FUTURE SHIFTS MAY NEED TO LOOK AT INCREASING THE
EAST WINDS INTO THE PDX METRO AREA THIS WEEKEND AS LATEST NAM RUNS
HAVE BEEN SHOWING KTTD-KDLS GRADIENTS OF -5 TO -7 MB...WHICH COULD
PRODUCE GUSTS 50-70 MPH AT THE WINDIER LOCATIONS OF THE WEST GORGE
AND 30-40 MPH NEAR TROUTDALE. THIS SEEMS FAIRLY REASONABLE GIVEN THE
COLD POOL SETUP EXPECTED TO TAKE PLACE EAST OF THE CASCADES THE NEXT
FEW DAYS. THE OFFSHORE FLOW WILL BRING A BREAK IN PRECIPITATION...
WITH A DECENT AMOUNT OF SUNSHINE OUTSIDE OF PATCHY VALLEY FOG AWAY
FROM THE GORGE. WEAGLE
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...MODELS CONTINUE TO
ADVERTISE A PRETTY MAJOR PATTERN CHANGE IN THE LATTER PART OF THE
EXTENDED PERIOD. SAT NIGHT AND SUN LOOK TO REMAIN DRY WITH SOME
DEGREE OF OFFSHORE LOW-LEVEL FLOW. THERMALLY-INDUCED SURFACE TROUGH
RESIDES ALONG THE COAST SAT NIGHT THEN WEAKENS SUN. SHOULD SEE A
FAIRLY LARGE MIN TEMP RANGE SAT NIGHT WITH SUBSIDENCE INVERSIONS IN
THE HIGHER TERRAIN. THINGS START TO GET INTERESTING MON AS AN UPPER
TROUGH DIVES SOUTH FROM THE GULF OF ALASKA. THE OPERATIONAL ECMWF AND
GFS ARE SIMILAR IN THE OVERALL LARGE-SCALE PATTERN. COLD FRONTAL
BOUNDARY SLIDES SOUTH THROUGH WASHINGTON MON WITH 1000-500 MB
THICKNESS VALUES LOWERING TO NEAR 530 DM ACROSS SW WA AND FAR NW
OREGON 00Z TUE. BOTH MODELS THEN SHOW A RE-ENFORCING SHOT OF COLDER
AIR DIGGING INTO THE UPPER TROUGH MON NIGHT AND TUE. BY 00Z WED THE
OPERATIONAL ECMWF HAS THICKNESS VALUES IN THE LOW TO MID 520S AND 850
MB TEMPS AROUND -6C OVER SW WA AND FAR NW OREGON. SHOULD THIS
VERIFY...SNOW LEVELS WOULD BE DOWN TO AT LEAST 1000 FT...IF NOT A
LITTLE LOWER. THE COLD PATTERN HOLDS THROUGH WED. THE ECMWF IS MUCH
SLOWER PUSHING THE UPPER TROUGH SOUTH COMPARED TO THE GFS. IN
FACT...THE GFS SHOWS NELY FLOW ALOFT WED WITH COLD AIR STACKING UP
AGAINST THE S WA AND N OREGON CASCADES. GFS HAS 850 MB TEMPS OF -10C
TO -12C OVER THE S WA AND N OREGON CASCADE CREST 18Z WED. STILL TOO
EARLY TO TRY AND PIN DOWN THE FINER DETAILS...BUT CONFIDENCE IS
GROWING THAT WE MAY ENDURE A MUCH COLDER AIR MASS THE FIRST PART OF
NEXT WEEK. WEISHAAR.
&&
.AVIATION...WARM FRONTAL RAIN PUSHING ACROSS THE REGION THIS
MORNING AS ASSOCIATED SURFACE LOW MOVES ONSHORE AND EAST ACROSS
THE AREA LATER THIS MORNING. MIX OF IFR AND MVFR ACROSS THE
SOUTHERN PORTIONS OF THE AREA IN MODERATE STEADY RAIN. BREEZY
CONDITIONS ALSO CONTINUE...PARTICULARLY ALONG THE CENTRAL OREGON
COAST. LITTLE IMPROVEMENT THROUGH EARLY AFTERNOON WITH LOWER MVFR
TO IFR CIGS CONTINUING.
KPDX AND APPROACHES...MVFR CIGS/VSBYS CONTINUE THIS MORNING IN
RAIN. MAY SEE LOWERING CIGS FOR A MIX OF IFR TO LOW MVFR CIGS
THROUGH MUCH OF THE MORNING AND PERHAPS THROUGH THE EARLY
AFTERNOON. SOME IMPROVEMENT IN CIGS LIKELY BY MID AFTERNOON INTO
THE EVENING. EAST WINDS REMAIN REMAIN 10 TO 20 KT EARLY THIS
MORNING...DECREASING BY AROUND MIDDAY. CULLEN
&&
.MARINE...SURFACE LOW PRESSURE CONTINUES TO APPROACH THE
COAST...PRESENTLY ENTERING THE COASTAL WATERS /OR 60 NM
OFFSHORE/ WEST OF CASCADE HEAD. SOLID SMALL CRAFT WINDS CONTINUE
OVER ALL WATERS...WITH EAST WINDS OVER THE NORTHERN WATERS NORTH
OF THE LOW AND SOUTH TO SOUTHEAST WINDS TO THE SOUTH. AS
EXPECTED...THE STRONGEST GUSTS HAVE BEEN TO THE SOUTH AND
IMMEDIATELY AHEAD OF THE LOW. THEREFORE...WHILE GUSTS HAVE
REMAINED JUST SHY OF GALE CRITERIA TO THIS POINT...THE WINDOW OF
STRONGEST WINDS WILL CONTINUE THROUGH AROUND 6 AM. THUS...THE GALE
WARNING REMAINS IN EFFECT.
WINDS TURN MORE NORTHERLY ONCE THE LOW MOVES ONSHORE EARLY
THURSDAY...WITH ADVISORY LEVEL GUSTS CONTINUING INTO THURSDAY
EVENING. THEN...OVERALL WEAKLY DEFINED SURFACE PATTERN FOR MORE
BENIGN CONDITIONS. A THERMAL LOW BUILDS UP THE COAST FRIDAY AND
MAY REMAIN ALONG THE COAST THROUGH THE WEEKEND FOR OFFSHORE FLOW.
SEAS SOUTH OF CASCADE HEAD WILL REMAIN 12 TO 14 FT THIS MORNING
AS THE LOW MOVES ACROSS...BUT CONTINUE TO SUBSIDE NORTH INTO THE 7
TO 9 FT RANGE. SEAS SOUTH WILL SUBSIDE TO LESS THAN 10 FT BY
THURSDAY EVENING. CULLEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR NORTHERN
OREGON CASCADES.
HIGH WIND WARNING UNTIL 7 AM PST THIS MORNING FOR CENTRAL COAST
RANGE OF WESTERN OREGON-CENTRAL OREGON COAST.
WA...WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR SOUTH
WASHINGTON CASCADES.
PZ...GALE WARNING UNTIL 8 AM PST THIS MORNING FOR COASTAL WATERS FROM
CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 8 AM
THIS MORNING TO NOON PST TODAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1047 PM EST FRI NOV 20 2015
.SYNOPSIS...
HIGH PRESSURE WILL RAPIDLY MOVE OVER AND THEN EAST OF OUR AREA
OVERNIGHT AS A FAST WAVE AND COLD FRONT APPROACHES FROM THE WEST
SATURDAY AFTERNOON. THIS WILL TRIGGER RAIN TO SNOW SHOWERS
OVERNIGHT SATURDAY INTO SUNDAY AND POSSIBLE LAKE EFFECT SNOW IN
NORTHWEST PENNSYLVANIA SUNDAY INTO SUNDAY NIGHT. IT WILL BE A TAD
COLDER THEN NORMAL SUNDAY-MONDAY. A RIDGE WILL BUILD TO OVER THE
CENTRAL US TUESDAY INTO THANKSGIVING PROVIDING A RELATIVELY DRY
PERIOD AND WARMING TREND. DEEP SOUTHWESTERLY FLOW LATE NEXT WEEK
COULD BRING A CHANCE OF RAIN/RAIN SHOWERS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
03Z IR LOOP SHOWING MID/HIGH LVL CLOUDINESS MOVING INTO CENTRAL
PA...AS WAA ALOFT OVERSPREADS THE REGION AHEAD OF SHORTWAVE OVR
THE PLAINS STATES. LATEST NEAR TERM MDL DATA SUGGESTS THE CLOUD
COVER WILL BE THICKEST ARND 06Z...THEN THIN OUT AND PUSH NORTHEAST
OF THE AREA TOWARD DAWN. THE LGT WIND AND VERY DRY AIR ASSOC WITH
SFC HIGH PRES WILL ALLOW TEMPS TO FALL INTO THE 20S FOR MOST OF
THE AREA. LATEST HRRR TIMESERIES SHOW TEMPS BOTTOMING OUT ARND
04Z...RISING A BIT AS CLOUDS ARRIVE...THEN REACHING A SECOND MIN
AT DAWN.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
RIDGE OF HIGH PRES ALONG THE E COAST SHOULD ENSURE A DRY SATURDAY
ACROSS CENTRAL PA. LIGHT WINDS EXPECTED FOR MOST...ALTHOUGH THE
HIGHER ELEVATIONS OF THE ALLEGHENY HIGHLANDS WILL SEE SOME
INCREASING SOUTHEAST BREEZES IN THE AFTERNOON. BUFKIT SUPPORTS
AFTN GUSTS BTWN 20-25KTS.
LATEST MDL DATA INDICATES 8-7H BAROCLINIC ZONE AND ASSOC MID LVL
CLOUDINESS WILL SHIFT NORTH OF PA ON SATURDAY. WILL MAINTAIN MCLDY
SKIES FOR NOW ACROSS THE N MTNS. HOWEVER...MUCH OF CENTRAL PA
SHOULD EXPERIENCE A MSUNNY SATURDAY. ENS MEAN 925MB TEMPS NR 2C
SHOULD BE SUPPORTIVE OF MAX TEMPS BTWN 45-50F.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
A FAST MOVING WAVE AND STRONG COLD FRONT WILL TRIGGER SOME LIGHT
RAIN WHICH WILL TURN TO SNOW QUICKLY IN THE NORTHWESTERN AREAS
SATURDAY NIGHT. FARTHER EAST VERY LIGHT RAIN LIKELY ENDING AS
SNOW SHOWERS OR FLURRIES SUNDAY. IT WILL TURN MARKEDLY COLDER
EARLY SUNDAY AND BREEZY.
THE COLD AIR...WARM LAKES AND WESTERLY WINDS INDICATE A POTENTIAL
ERIE SNOW BAND. AT THIS TIME SREF IS SUGGESTING 2-4 INCHES
POSSIBLE NEAR NY BORDER...BUT BEST SNOW IS LIKELY TO THE NORTH OF
THE PA/NY BORDER. WE WILL WAIT TO SEE 3KM NCAR ENSEMBLE TONIGHT
AND HOW IT FORECASTS THE SNOW. WE SHOWED GENERALLY 1-3 INCHES AT
THIS TIME IN THE LES EVENT AND WILL WAIT FOR HIGHER RESOLUTION
GUIDANCE.
SUNDAY WILL BE COLD AND BREEZY. THE COLD AIR SHOULD SLOWLY EASE ON
MONDAY INTO MONDAY NIGHT. WE BOTTOM OUT -1 TO -1.5SD BELOW NORMAL
FOR 850 MB TEMPS SUNDAY INTO MONDAY EVENING.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
MINOR ADJUSTMENTS TO 03Z TAFS.
EARLIER DISCUSSION BELOW.
LOOKING AT CLEAR SKIES THIS EVENING WITH WINDS ON THE DECREASE.
SOME MID AND HIGH CLDS LATE TONIGHT INTO SAT. WINDS WILL PICK
UP ACROSS THE WEST BY LATE MORNING...AND LATE IN THE DAY IN
THE EAST.
MOISTURE IS LIMITED...THUS THE AREA SHOULD REMAIN MAINLY DRY
PRIOR TO 00Z SUNDAY.
A LOT OF DIRECTIONAL SHEAR EARLY SUNDAY. LATER IN THE DAY ON
SUNDAY INTO TUE...AS WINDS BECOME MORE WESTERLY...AND THE COLD
AIR DEEPENS...SOME SNOW SHOWERS POSSIBLE...MAINLY AT BFD.
OTHERWISE THE WEATHER PATTERN LOOKS TO BE A QUIET ONE INTO THE
MIDDLE OF NEXT WEEK.
OUTLOOK...
SUN...MVFR CIGS WEST TO VFR EAST. IFR VIS PSBL NW IN SHSN.
MON...MVFR-VFR CIGS WEST. NO SIG WX.
TUE...MVVR NW WITH CHC -SHSN...VFR/NO SIG WX ELSEWHERE.
WED...VFR/NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...GRUMM
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1031 PM EST FRI NOV 20 2015
.SYNOPSIS...
HIGH PRESSURE WILL RAPIDLY MOVE OVER AND THEN EAST OF OUR AREA
OVERNIGHT AS A FAST WAVE AND COLD FRONT APPROACHES FROM THE WEST
SATURDAY AFTERNOON. THIS WILL TRIGGER RAIN TO SNOW SHOWERS
OVERNIGHT SATURDAY INTO SUNDAY AND POSSIBLE LAKE EFFECT SNOW IN
NORTHWEST PENNSYLVANIA SUNDAY INTO SUNDAY NIGHT. IT WILL BE A TAD
COLDER THEN NORMAL SUNDAY-MONDAY. A RIDGE WILL BUILD TO OVER THE
CENTRAL US TUESDAY INTO THANKSGIVING PROVIDING A RELATIVELY DRY
PERIOD AND WARMING TREND. DEEP SOUTHWESTERLY FLOW LATE NEXT WEEK
COULD BRING A CHANCE OF RAIN/RAIN SHOWERS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
SFC HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE OHIO VALLEY
TONIGHT...PROVIDING MCLEAR SKIES AND DIMINISHING WIND THIS
EVENING THEN INCREASING MID/HIGH CLOUDS ARND MIDNIGHT...AS WAA
ALOFT OVERSPREADS THE REGION AHEAD OF SHORTWAVE OVR THE PLAINS
STATES.
LATEST NEAR TERM MDL DATA SUGGESTS THE CLOUD COVER WILL BE
THICKEST ARND 06Z...THEN THIN OUT AND PUSH NORTHEAST OF THE AREA
TOWARD DAWN. THE LGT WIND AND VERY DRY AIR WILL ALLOW TEMPS TO
FALL INTO THE 20S FOR MOST OF THE AREA. LATEST HRRR TIMESERIES
SHOW TEMPS BOTTOMING OUT ARND 04Z...RISING AS CLOUDS ARRIVE...THEN
REACHING A SECOND MIN AT DAWN.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
RIDGE OF HIGH PRES ALONG THE E COAST SHOULD ENSURE A DRY SATURDAY
ACROSS CENTRAL PA. LIGHT WINDS EXPECTED FOR MOST...ALTHOUGH THE
HIGHER ELEVATIONS OF THE ALLEGHENY HIGHLANDS WILL SEE SOME
INCREASING SOUTHEAST BREEZES IN THE AFTERNOON. BUFKIT SUPPORTS
AFTN GUSTS BTWN 20-25KTS.
LATEST MDL DATA INDICATES 8-7H BAROCLINIC ZONE AND ASSOC MID LVL
CLOUDINESS WILL SHIFT NORTH OF PA ON SATURDAY. WILL MAINTAIN MCLDY
SKIES FOR NOW ACROSS THE N MTNS. HOWEVER...MUCH OF CENTRAL PA
SHOULD EXPERIENCE A MSUNNY SATURDAY. ENS MEAN 925MB TEMPS NR 2C
SHOULD BE SUPPORTIVE OF MAX TEMPS BTWN 45-50F.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
A FAST MOVING WAVE AND STRONG COLD FRONT WILL TRIGGER SOME LIGHT
RAIN WHICH WILL TURN TO SNOW QUICKLY IN THE NORTHWESTERN AREAS
SATURDAY NIGHT. FARTHER EAST VERY LIGHT RAIN LIKELY ENDING AS
SNOW SHOWERS OR FLURRIES SUNDAY. IT WILL TURN MARKEDLY COLDER
EARLY SUNDAY AND BREEZY.
THE COLD AIR...WARM LAKES AND WESTERLY WINDS INDICATE A POTENTIAL
ERIE SNOW BAND. AT THIS TIME SREF IS SUGGESTING 2-4 INCHES
POSSIBLE NEAR NY BORDER...BUT BEST SNOW IS LIKELY TO THE NORTH OF
THE PA/NY BORDER. WE WILL WAIT TO SEE 3KM NCAR ENSEMBLE TONIGHT
AND HOW IT FORECASTS THE SNOW. WE SHOWED GENERALLY 1-3 INCHES AT
THIS TIME IN THE LES EVENT AND WILL WAIT FOR HIGHER RESOLUTION
GUIDANCE.
SUNDAY WILL BE COLD AND BREEZY. THE COLD AIR SHOULD SLOWLY EASE ON
MONDAY INTO MONDAY NIGHT. WE BOTTOM OUT -1 TO -1.5SD BELOW NORMAL
FOR 850 MB TEMPS SUNDAY INTO MONDAY EVENING.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
MINOR ADJUSTMENTS TO 03Z TAFS.
EARLIER DISCUSSION BELOW.
LOOKING AT CLEAR SKIES THIS EVENING WITH WINDS ON THE DECREASE.
SOME MID AND HIGH CLDS LATE TONIGHT INTO SAT. WINDS WILL PICK
UP ACROSS THE WEST BY LATE MORNING...AND LATE IN THE DAY IN
THE EAST.
MOISTURE IS LIMITED...THUS THE AREA SHOULD REMAIN MAINLY DRY
PRIOR TO 00Z SUNDAY.
A LOT OF DIRECTIONAL SHEAR EARLY SUNDAY. LATER IN THE DAY ON
SUNDAY INTO TUE...AS WINDS BECOME MORE WESTERLY...AND THE COLD
AIR DEEPENS...SOME SNOW SHOWERS POSSIBLE...MAINLY AT BFD.
OTHERWISE THE WEATHER PATTERN LOOKS TO BE A QUIET ONE INTO THE
MIDDLE OF NEXT WEEK.
OUTLOOK...
SUN...MVFR CIGS WEST TO VFR EAST. IFR VIS PSBL NW IN SHSN.
MON...MVFR-VFR CIGS WEST. NO SIG WX.
TUE...MVVR NW WITH CHC -SHSN...VFR/NO SIG WX ELSEWHERE.
WED...VFR/NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...GRUMM
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
714 PM EST FRI NOV 20 2015
.SYNOPSIS...
HIGH PRESSURE WILL RAPIDLY MOVE OVER AND THEN EAST OF OUR AREA
OVERNIGHT AS A FAST WAVE AND COLD FRONT APPROACHES FROM THE WEST
SATURDAY AFTERNOON. THIS WILL TRIGGER RAIN TO SNOW SHOWERS
OVERNIGHT SATURDAY INTO SUNDAY AND POSSIBLE LAKE EFFECT SNOW IN
NORTHWEST PENNSYLVANIA SUNDAY INTO SUNDAY NIGHT. IT WILL BE A TAD
COLDER THEN NORMAL SUNDAY-MONDAY. A RIDGE WILL BUILD TO OVER THE
CENTRAL US TUESDAY INTO THANKSGIVING PROVIDING A RELATIVELY DRY
PERIOD AND WARMING TREND. DEEP SOUTHWESTERLY FLOW LATE NEXT WEEK
COULD BRING A CHANCE OF RAIN/RAIN SHOWERS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
SFC HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE OHIO VALLEY
TONIGHT...PROVIDING MCLEAR SKIES AND DIMINISHING WIND THIS
EVENING THEN INCREASING MID/HIGH CLOUDS ARND MIDNIGHT...AS WAA
ALOFT OVERSPREADS THE REGION AHEAD OF SHORTWAVE OVR THE PLAINS
STATES.
LATEST NEAR TERM MDL DATA SUGGESTS THE CLOUD COVER WILL BE
THICKEST ARND 06Z...THEN THIN OUT AND PUSH NORTHEAST OF THE AREA
TOWARD DAWN. THE LGT WIND AND VERY DRY AIR WILL ALLOW TEMPS TO
FALL INTO THE 20S FOR MOST OF THE AREA. LATEST HRRR TIMESERIES
SHOW TEMPS BOTTOMING OUT ARND 04Z...RISING AS CLOUDS ARRIVE...THEN
REACHING A SECOND MIN AT DAWN.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
RIDGE OF HIGH PRES ALONG THE E COAST SHOULD ENSURE A DRY SATURDAY
ACROSS CENTRAL PA. LIGHT WINDS EXPECTED FOR MOST...ALTHOUGH THE
HIGHER ELEVATIONS OF THE ALLEGHENY HIGHLANDS WILL SEE SOME
INCREASING SOUTHEAST BREEZES IN THE AFTERNOON. BUFKIT SUPPORTS
AFTN GUSTS BTWN 20-25KTS.
LATEST MDL DATA INDICATES 8-7H BAROCLINIC ZONE AND ASSOC MID LVL
CLOUDINESS WILL SHIFT NORTH OF PA ON SATURDAY. WILL MAINTAIN MCLDY
SKIES FOR NOW ACROSS THE N MTNS. HOWEVER...MUCH OF CENTRAL PA
SHOULD EXPERIENCE A MSUNNY SATURDAY. ENS MEAN 925MB TEMPS NR 2C
SHOULD BE SUPPORTIVE OF MAX TEMPS BTWN 45-50F.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
A FAST MOVING WAVE AND STRONG COLD FRONT WILL TRIGGER SOME LIGHT
RAIN WHICH WILL TURN TO SNOW QUICKLY IN THE NORTHWESTERN AREAS
SATURDAY NIGHT. FARTHER EAST VERY LIGHT RAIN LIKELY ENDING AS
SNOW SHOWERS OR FLURRIES SUNDAY. IT WILL TURN MARKEDLY COLDER
EARLY SUNDAY AND BREEZY.
THE COLD AIR...WARM LAKES AND WESTERLY WINDS INDICATE A POTENTIAL
ERIE SNOW BAND. AT THIS TIME SREF IS SUGGESTING 2-4 INCHES
POSSIBLE NEAR NY BORDER...BUT BEST SNOW IS LIKELY TO THE NORTH OF
THE PA/NY BORDER. WE WILL WAIT TO SEE 3KM NCAR ENSEMBLE TONIGHT
AND HOW IT FORECASTS THE SNOW. WE SHOWED GENERALLY 1-3 INCHES AT
THIS TIME IN THE LES EVENT AND WILL WAIT FOR HIGHER RESOLUTION
GUIDANCE.
SUNDAY WILL BE COLD AND BREEZY. THE COLD AIR SHOULD SLOWLY EASE ON
MONDAY INTO MONDAY NIGHT. WE BOTTOM OUT -1 TO -1.5SD BELOW NORMAL
FOR 850 MB TEMPS SUNDAY INTO MONDAY EVENING.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LOOKING AT CLEAR SKIES THIS EVENING WITH WINDS ON THE DECREASE.
SOME MID AND HIGH CLDS LATE TONIGHT INTO SAT. WINDS WILL PICK
UP ACROSS THE WEST BY LATE MORNING...AND LATE IN THE DAY IN
THE EAST.
MOISTURE IS LIMITED...THUS THE AREA SHOULD REMAIN MAINLY DRY
PRIOR TO 00Z SUNDAY.
A LOT OF DIRECTIONAL SHEAR EARLY SUNDAY. LATER IN THE DAY ON
SUNDAY INTO TUE...AS WINDS BECOME MORE WESTERLY...AND THE COLD
AIR DEEPENS...SOME SNOW SHOWERS POSSIBLE...MAINLY AT BFD.
OTHERWISE THE WEATHER PATTERN LOOKS TO BE A QUIET ONE INTO THE
MIDDLE OF NEXT WEEK.
OUTLOOK...
SUN...MVFR CIGS WEST TO VFR EAST. IFR VIS PSBL NW IN SHSN.
MON...MVFR-VFR CIGS WEST. NO SIG WX.
TUE...MVVR NW WITH CHC -SHSN...VFR/NO SIG WX ELSEWHERE.
WED...VFR/NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...GRUMM
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1233 AM EST THU NOV 19 2015
.SYNOPSIS...
MODERATE RAIN IS EXPECTED OVERNIGHT BEFORE A COLD FRONT PUSHES
ACROSS PENNSYLVANIA ON THURSDAY. IT WILL DRY OUT THURSDAY NIGHT
INTO FRIDAY AS HIGH PRESSURE BUILDS INTO THE UPPER OHIO VALLEY. A
SECOND COLD FRONT WILL MOVE THROUGH LATE IN THE WEEKEND. THE MILD
TEMPERATURES WILL PEAK ON THURSDAY FOLLOWED BY A COLDER PATTERN
FOR THE WEEKEND INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
05Z OBS AND MDL SOUNDINGS SUGGEST WGUSTS WILL REMAIN BLW ADVISORY
CRITERIA ACROSS THE LAUREL HIGHLANDS...SO HAVE ALLOWED WIND ADV
OVR SOMERSET/CAMBRIA COS TO EXPIRE. REGIONAL RADAR MOSAIC AT 05Z
SHOWS A SOLID LINE OF RAIN MOVING INTO WESTERN PA ASSOC WITH PLUME
OF ANOMALOUS PWATS AHEAD OF APPROACHING SHORTWAVE. RADAR TRENDS
AND LATEST SREF/GEFS OUTPUT SUPPORT POPS CLOSE TO 100 PCT
OVERNIGHT. ALTHOUGH AREAS OF DZ HAVE FORMED ACROSS THE EASTERN
HALF OF THE STATE...THE MORE SIG RAIN REMAINS WEST OF KUNV/KAOO AT
05Z. LINEAR EXTRAPOLATION AND HRRR GUIDANCE INDICATE THE MORE SIG
RAIN WILL REACH THE SUSQ RIVER BTWN 08Z-09Z AND
SCHUYLKILL/LANCASTER COS BY 10Z-11Z.
TEMPS WILL LIKELY FALL A COUPLE OF DEGREES AS RAIN ARRIVES...BUT
IT WILL REMAIN A VERY WARM NIGHT FOR NOVEMBER DUE TO SOUTHERLY
FLOW/SURGE OF WARMTH AHEAD OF APPROACHING COLD/OCCLUDED FRONT.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM FRIDAY/...
AREA OF RAIN WILL PUSH INTO THE SUSQUEHANNA VALLEY EARLY THURSDAY
BEFORE SHIFTING EAST INTO NJ LATER IN THE AFTERNOON/EVENING. STORM
TOTAL QPF AMTS ARE SOLIDLY IN THE 0.50 TO 1 INCH RANGE WITH SOME
LOCALIZED HIGHER AMOUNTS POSSIBLE ESPECIALLY IN REGIONS WHERE THE
OROGRAPHICS FOCUS AND ENHANCE LOW LEVEL LIFT. THE HI-RES SHORT
TERM MODELS AND ENSEMBLES SHOW THIS SE FLOW TERRAIN ENHANCEMENT
PRETTY WELL. PWS QUICKLY DECREASE AS MUCH DRIER AIR ARRIVES FROM
WEST TO EAST BEHIND THE FRONT DURING THE DAY ON THURSDAY. THIS
SHOULD BRING AN END TO THE SHOWERS OVER EASTERN PORTIONS OF THE
CWA BY 00Z FRIDAY.
TEMPS WILL PEAK ON THURSDAY WITH HIGHS 10-15 DEGREES ABOVE
CLIMO...BEFORE COLDER AIR WORKS IN THU NIGHT.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD INTO THE REGION FRIDAY WITH COOLER AND
DRIER WEATHER. EXTENDED MODELS STARTING TO COME TO SOME AGREEMENT
ON THE THE STORM TRACK AND AMOUNT OF COLDER AIR MOVING INTO THE
STATE LATER SATURDAY. 850 TEMPS SHOULD DROP BELOW ZERO OVER THE
ENTIRE STATE SATURDAY NIGHT WITH SNOW SHOWERS ACROSS THE NORTHWEST
AND A FEW FLURRIES OVER THE SOUTHEAST.
COOLER AIR CONTINUES INTO THE FIRST HALF OF THE WEEK BEFORE A
RETURN TO THE RELATIVELY MILD PATTERN BY MIDWEEK. ANOTHER HIGH
PRESSURE MOVING SOUTHEAST THROUGH NEW ENGLAND BY THE END OF THE
PERIOD MAY TEMPER THE MILD READINGS WITH A POSSIBLE BACK DOOR
FRONT LATE IN THE PERIOD.
&&
.AVIATION /05Z THURSDAY THROUGH MONDAY/...
SOME ADJUSTMENTS MADE TO THE TAFS THIS EVENING. SMALL
BANDS OF DRIZZLE AHEAD OF BAND OF SHOWERS OVER WESTERN PA
AT 11 PM.
EARLIER DISCUSSION BELOW.
GUSTY WINDS AND LLWS WILL BE THE MAIN ISSUE OVERNIGHT.
EXPECT LOW CIGS ACROSS THE WEST...ALONG WITH SOME RAIN AND
SHOWERS.
FURTHER EAST...STILL A FEW SPOTS WITH VFR CONDITIONS...BUT
EXPECT CONDITIONS TO BECOME MVFR AND IFR LATER ON.
SOME HZ/BR AT UNV AT TIMES SINCE MID AFT.
MAIN LINE OF SHOWERS STILL WELL TO THE WEST. SEPERATE AREA OF
SHOWERS JUST SOUTH OF JST.
PERHAPS A RUMBLE OF THUNDER WITH THE COLD FRONT...BUT 500 MB
HEIGHTS REALLY ARE NOT THAT LOW...AND INSTABILITY LIMITED
THIS TIME OF DAY.
IMPROVING CONDITIONS FOR THE LATER PART OF THU...AS DRY
SLOT MOVES IN.
OUTLOOK...
FRI...NO SIG WX EXPECTED.
SAT-SUN...LIGHT SNOW/REDUCED VSBYS POSSIBLE W MTNS SAT AFTERNOON
INTO SUNDAY...WITH MAINLY VFR IN MORE SCATTERED SNOW OR RAIN
SHOWERS CENTRAL AND SE PA.
MON...IMPROVING CONDITIONS AS HIGH PRESSURE BUILDS IN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/RXR
NEAR TERM...DANGELO/FITZGERALD
SHORT TERM...RXR
LONG TERM...STEINBUGL/TYBURSKI
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
438 PM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST TONIGHT
THROUGH THE EARLY PART OF THE WEEKEND. A VIGOROUS COLD FRONT WILL
CROSS THE AREA FROM THE WEST SATURDAY NIGHT INTO SUNDAY...USHERING
IN THE COOLEST AIR OF THE SEASON SO FAR. DRY HIGH PRESSURE WILL THEN
RETURN FROM THE WEST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
430 PM UPDATE...TOUCHED UP T/TD TRENDS INTO THE EVENING...CORRECTING
VALUES FOR FRONTAL TIMING SOMEWHAT. MIXING IN THE WAKE OF THE
FRONT HAS BROUGHT DEWPTS DOWN HARD IN A FEW SPOTS AS WELL. I ALSO
REMOVED THE MENTION OF SHOWERS IMMEDIATELY AHEAD OF THE FRONT /EAST
OF CHARLOTTE/ THAT REMAINED LATE IN THE AFTN...SATELLITE JUST NOT
SUGGESTING CLOUDS ARE DEEP ENOUGH FOR SHOWERS. OTHERWISE THE FCST
IS ON TRACK.
AS OF 220 PM EST...A SURFACE COLD FRONT HAS REACHED THE INTERSTATE
77 CORRIDOR THIS AFTERNOON AND CONTINUES TO MAKE STEADY EASTWARD
PROGRESS. THIS HAS BEEN ACCOMPANIED BY GENERAL CLEARING...BUT
THE THE HIGHER LEVEL CIRRUS REMAINS PESKY ACROSS THE PIEDMONT AS
AN UPPER JETLET MOVING ACROSS THE APPALACHIANS SHARPENS UP UPPER
LEVEL DIVERGENCE OVER THE PIEDMONT. THIS WEAK UPPER SUPPORT WILL BE
COINCIDENT WITH A PASSING 500 MB SHORTWAVE LATE TODAY. PROFILES ARE
BECOMING INCREASINGLY DRY WITH THE FROPA...AND THE MESOSCALE MODELS
GENERALLY KEEP ANY RESULTANT SHOWERS JUST EAST OF THE FORECAST AREA.
THE LATEST HRRR DOES PRODUCE SOME ISOLD SHOWER ACTIVITY ALONG/EAST
OF THE INTERSTATE 77 CORRIDOR LATE DAY BUT SLIGHT CHANCES WILL BE
CONFINED MAINLY TO UNION COUNTY NC.
OTHERWISE...NW DOWNSLOPING FLOW ALONG WITH 850 MB COLD ADVECTION
WILL PICK UP TONIGHT AS SURFACE HIGH PRESSURE BUILDS IN FROM
THE WEST. SOME SHALLOW MOISTURE MAY LINGER ALONG THE SPINE OF
THE SRN APPALACHIANS BUT WITH LITTLE MORE THAN CLOUDS EXPECTED
IN NW UPSLOPE FLOW AREAS. THE PRES GRADIENT WILL BE RELATIVELY
TIGHT TONIGHT AS THE SURFACE HIGH BUILDS FROM THE MID MS VALLEY
TO THE CENTRAL APPALACHIANS...WHICH SHOULD KEEP MOST FOG PROBLEMS
AT BAY DESPITE THE MOIST GROUND. ANOTHER WEAK SHORTWAVE WILL PASS
OVERNIGHT IN THE INCREASINGLY ZONAL FLOW ALOFT...BUT WITH LITTLE
TO NO DEEP MOISTURE LEFT.
SOME BROAD CYCLONIC CURVATURE WILL DEVELOP IN THE FLOW ON FRIDAY
AS HEIGHTS FALL FROM THE ROCKIES INTO THE PLAINS. DOWNSLOPING
WILL CONTINUE AT LOW LEVELS...BUT 850 MB TEMPS SHOULD BE ABOUT 5
DEGREES C COOLER BY FRI AFTN COMPARED TO TODAY...WITH MAXES ABOUT
10 DEGREES LESS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM THURSDAY...MODEL GUIDANCE IN AGREEMENT ON A SERIES OF
SHORTWAVES CARVING OUT A LARGE UPPER TROF ACRS THE GREAT LAKES TO
THE GULF STATES OVER THE WEEKEND. THIS WILL PUT OUR AREA UNDER DEEP
LAYER INCREASING SOUTHWESTERLY FLOW AHEAD OF THE TROF AXIS. AT THE
SFC...A CLIPPER SYSTEM WILL DIP INTO THE MIDWEST...THEN LIFT INTO
THE GREAT LAKES. THE SYSTEM WILL DRAG A COLD FRONT ACRS THE OHIO
VALLEY ON SATURDAY...THEN ACRS THE CWFA SATURDAY NIGHT INTO SUNDAY
MORNING. THERE SHUD BE A BRIEF WINDOW WHERE MOISTURE WILL BE DEEP
ENUF WITH THE LLVL FORCING TO SQUEEZE OUT A FEW SHWRS ALONG THE TN
LINE SATURDAY NIGHT. THE ISSUE IS HOW COLD WILL THE PBL BE FOR SNOW.
IT STILL LOOK LIKE THE HIGHEST ELEVATIONS SHUD SEE A CHANGEOVER/MIX
BEFORE THE PRECIP ENDS AROUND DAYBREAK SUNDAY. ONLY VERY MINOR
ACCUMS ARE EXPECTED...IF ANY. EAST OF THE MTNS...THERE IS MORE
DISAGREEMENT AMONG THE GUIDANCE...AS A WEAK LOW PRES WAVE DEVELOPS
ALONG A STALLED FRONT OFF THE SOUTH ATLANTIC COAST. THE NAM IS AN
OUTLIER IN BRINGING A ROUND OF DEEP MOISTURE AND STOUT QPF RESPONSE
ACRS GA/SC. MEANWHILE...THE GFS HAS BEEN CONSISTENT ON KEEPING THE
PIEDMONT DRY. THE LAST TWO RUNS OF THE ECMWF HAVE SOME LIGHT QPF
MAINLY FROM I-85 AND SOUTH. THE WPC PREFERS THE ECWMF DEPICTION...SO
I HAVE ADDED A SLGT CHC TO LOW-END CHC POP ACRS THE PIEDMONT
SATURDAY NIGHT. I ALSO BUMPED MIN TEMPS UP...AS STRONG WAA AND
CLOUDS SHUD LIMIT COOLING.
ON SUNDAY...THE FRONT SHUD CLEAR THE AREA...ALLOWING LLVL FLOW TO
TURN OUT OF THE NW AND BRING STRONG CAA THRU THE AFTN. SKIES SHUD
CLEAR OUT...AND TEMPS WILL BE WELL BELOW NORMAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 125 PM THURSDAY...WE APPRECIATE WHAT LOOKS TO BE A QUIET AND
DRY PERIOD IN THE RUN UP TO THANKSGIVING. THE AXIS OF AN UPPER TROF
SHOULD SWING EASTWARD ACROSS THE FCST AREA SUNDAY NIGHT WITH LITTLE
FANFARE. IN ITS WAKE...A FLAT UPPER RIDGE WILL BUILD IN AND CARRY
SURFACE HIGH PRESSURE ACROSS THE REGION MONDAY NIGHT AND TUESDAY. IF
THERE IS A MINOR PROBLEM...IT MIGHT BE LOW TEMPS SUNDAY NIGHT/EARLY
MONDAY MORNING. MODEL GUIDANCE SHOWS SUB-FREEZING TEMPS BY SUNRISE
MONDAY...SO IF ALL GOES ACCORDING TO PLAN...THAT WILL TAKE CARE OF
OUR REMAINING FCST ZONES WHERE A FREEZE HAS NOT YET OCCURRED THIS
AUTUMN. THE UPPER RIDGE WILL START TO AMPLIFY OVER THE EAST DURING
MIDWEEK AND THAT WILL BUILD THE SURFACE HIGH AND RELOCATE IT TO OUR
NE FOR WEDNESDAY AND THURSDAY. EXPECT A SLOW WARMING TREND FOR THE
EARLY PART OF THE WEEK...THEN A SMALL JUMP UPWARD IN TEMPS FOR
MIDWEEK... BUT STILL BELOW NORMAL.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
AT KCLT...MVFR LEVEL CLOUDS CONTINUE TO SLOWLY LIFT AND SCATTER THIS
AFTN AS DRIER AIR WORKS IN FROM THE WEST...BUT UPPER LEVEL CLOUDS
WILL BE SLOWER TO CLEAR GIVEN THE SHARPENING UPPER JETLET OVER THE
APPALACHIANS. A FEW MESOSCALE MODELS PRODUCE LATE AFTERNOON SHOWERS
JUST EAST OF KCLT...BUT THIS APPEARS GENERALLY OVERDONE WITH MOST OF
THE FORCING AND LINGERING INSTABILITY EAST OF THE AREA. LIGHT WSW
WINDS SHOULD QUICKLY TOGGLE NW THIS AFTERNOON AND VEER TOWARD NRLY
OVERNIGHT. ALTHOUGH THE GROUND REMAINS MOIST AND SHALLOW FOG MAY
BECOME A CONCERN...NRLY MIXING OVERNIGHT SHOULD LARGELY PRECLUDE
RESTRICTIONS.
ELSEWHERE...LITTLE MORE THAN FEW TO SCT HIGH CLOUDS ARE EXPECTED
ACROSS THE TERMINAL FORECAST AREA GOING FORWARD. WINDS WILL CONTINUE
TO VEER NW THEN NRLY TONIGHT AS HIGH PRESSURE APPROACHES FROM THE
WEST. OCCASIONAL LOW END GUSTS ARE EXPECTED AT KAVL AS COLD
ADVECTION INCREASES BEHIND THE DEPARTING FRONT. PATCHY FOG WILL BE
POSSIBLE IN SHELTERED AREAS GIVEN THE MOIST GROUND...BUT MIXING ON
NRLY FLOW SHOULD LARGELY PRECLUDE RESTRICTIONS.
OUTLOOK...DRY HIGH PRESSURE WILL KEEP CONDITIONS VFR THROUGH SAT. A
SECONDARY COLD FRONT COULD BRING SCATTERED SHOWERS MAINLY TO THE
MOUNTAINS SAT NIGHT INTO EARLY SUNDAY...WITH SOME HIGH ELEVATION
SNOW POSSIBLE ALONG THE HIGHEST PEAKS...BUT WITH SMALL CHANCES OF
ANY RESTRICTIONS DOWN AT KAVL. DRY HIGH PRES WILL RETURN THROUGH
EARLY NEXT WEEK.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-18Z
KCLT HIGH 96% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...HG/WIMBERLEY
SHORT TERM...ARK
LONG TERM...ARK
AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
224 PM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST TONIGHT
THROUGH THE EARLY PART OF THE WEEKEND. A VIGOROUS COLD FRONT WILL
CROSS THE AREA FROM THE WEST SATURDAY NIGHT INTO SUNDAY...USHERING
IN THE COOLEST AIR OF THE SEASON SO FAR. DRY HIGH PRESSURE WILL THEN
RETURN FROM THE WEST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 220 PM EST...A SURFACE COLD FRONT HAS REACHED THE INTERSTATE
77 CORRIDOR THIS AFTERNOON AND CONTINUES TO MAKE STEADY EASTWARD
PROGRESS. THIS HAS BEEN ACCOMPANIED BY GENERAL CLEARING...BUT THE
THE HIGHER LEVEL CIRRUS REMAINS PESKY ACROSS THE PIEDMONT AS AN
UPPER JETLET MOVING ACROSS THE APPALACHIANS SHARPENS UP UPPER LEVEL
DIVERGENCE OVER THE PIEDMONT. THIS WEAK UPPER SUPPORT WILL BE
COINCIDENT WITH A PASSING 500 MB SHORTWAVE LATE TODAY. PROFILES ARE
BECOMING INCREASINGLY DRY WITH THE FROPA...AND THE MESOSCALE MODELS
GENERALLY KEEP ANY RESULTANT SHOWERS JUST EAST OF THE FORECAST AREA.
THE LATEST HRRR DOES PRODUCE SOME ISOLD SHOWER ACTIVITY ALONG/EAST
OF THE INTERSTATE 77 CORRIDOR LATE DAY BUT SLIGHT CHANCES WILL BE
CONFINED MAINLY TO UNION COUNTY NC.
OTHERWISE...NW DOWNSLOPING FLOW ALONG WITH 850 MB COLD ADVECTION
WILL PICK UP TONIGHT AS SURFACE HIGH PRESSURE BUILDS IN FROM THE
WEST. SOME SHALLOW MOISTURE MAY LINGER ALONG THE SPINE OF THE SRN
APPALACHIANS BUT WITH LITTLE MORE THAN CLOUDS EXPECTED IN NW UPSLOPE
FLOW AREAS. THE PRES GRADIENT WILL BE RELATIVELY TIGHT TONIGHT AS
THE SURFACE HIGH BUILDS FROM THE MID MS VALLEY TO THE CENTRAL
APPALACHIANS...WHICH SHOULD KEEP MOST FOG PROBLEMS AT BAY DESPITE
THE MOIST GROUND. ANOTHER WEAK SHORTWAVE WILL PASS OVERNIGHT IN THE
INCREASINGLY ZONAL FLOW ALOFT...BUT WITH LITTLE TO NO DEEP MOISTURE
LEFT.
SOME BROAD CYCLONIC CURVATURE WILL DEVELOP IN THE FLOW ON FRIDAY AS
HEIGHTS FALL FROM THE ROCKIES INTO THE PLAINS. DOWNSLOPING WILL
CONTINUE AT LOW LEVELS...BUT 850 MB TEMPS SHOULD BE ABOUT 5 DEGREES
C COOLER BY FRI AFTN COMPARED TO TODAY...WITH MAXES ABOUT 10 DEGREES
LESS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM THURSDAY...MODEL GUIDANCE IN AGREEMENT ON A SERIES OF
SHORTWAVES CARVING OUT A LARGE UPPER TROF ACRS THE GREAT LAKES TO
THE GULF STATES OVER THE WEEKEND. THIS WILL PUT OUR AREA UNDER DEEP
LAYER INCREASING SOUTHWESTERLY FLOW AHEAD OF THE TROF AXIS. AT THE
SFC...A CLIPPER SYSTEM WILL DIP INTO THE MIDWEST...THEN LIFT INTO
THE GREAT LAKES. THE SYSTEM WILL DRAG A COLD FRONT ACRS THE OHIO
VALLEY ON SATURDAY...THEN ACRS THE CWFA SATURDAY NIGHT INTO SUNDAY
MORNING. THERE SHUD BE A BRIEF WINDOW WHERE MOISTURE WILL BE DEEP
ENUF WITH THE LLVL FORCING TO SQUEEZE OUT A FEW SHWRS ALONG THE TN
LINE SATURDAY NIGHT. THE ISSUE IS HOW COLD WILL THE PBL BE FOR SNOW.
IT STILL LOOK LIKE THE HIGHEST ELEVATIONS SHUD SEE A CHANGEOVER/MIX
BEFORE THE PRECIP ENDS AROUND DAYBREAK SUNDAY. ONLY VERY MINOR
ACCUMS ARE EXPECTED...IF ANY. EAST OF THE MTNS...THERE IS MORE
DISAGREEMENT AMONG THE GUIDANCE...AS A WEAK LOW PRES WAVE DEVELOPS
ALONG A STALLED FRONT OFF THE SOUTH ATLANTIC COAST. THE NAM IS AN
OUTLIER IN BRINGING A ROUND OF DEEP MOISTURE AND STOUT QPF RESPONSE
ACRS GA/SC. MEANWHILE...THE GFS HAS BEEN CONSISTENT ON KEEPING THE
PIEDMONT DRY. THE LAST TWO RUNS OF THE ECMWF HAVE SOME LIGHT QPF
MAINLY FROM I-85 AND SOUTH. THE WPC PREFERS THE ECWMF DEPICTION...SO
I HAVE ADDED A SLGT CHC TO LOW-END CHC POP ACRS THE PIEDMONT
SATURDAY NIGHT. I ALSO BUMPED MIN TEMPS UP...AS STRONG WAA AND
CLOUDS SHUD LIMIT COOLING.
ON SUNDAY...THE FRONT SHUD CLEAR THE AREA...ALLOWING LLVL FLOW TO
TURN OUT OF THE NW AND BRING STRONG CAA THRU THE AFTN. SKIES SHUD
CLEAR OUT...AND TEMPS WILL BE WELL BELOW NORMAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 125 PM THURSDAY...WE APPRECIATE WHAT LOOKS TO BE A QUIET AND
DRY PERIOD IN THE RUN UP TO THANKSGIVING. THE AXIS OF AN UPPER TROF
SHOULD SWING EASTWARD ACROSS THE FCST AREA SUNDAY NIGHT WITH LITTLE
FANFARE. IN ITS WAKE...A FLAT UPPER RIDGE WILL BUILD IN AND CARRY
SURFACE HIGH PRESSURE ACROSS THE REGION MONDAY NIGHT AND TUESDAY. IF
THERE IS A MINOR PROBLEM...IT MIGHT BE LOW TEMPS SUNDAY NIGHT/EARLY
MONDAY MORNING. MODEL GUIDANCE SHOWS SUB-FREEZING TEMPS BY SUNRISE
MONDAY...SO IF ALL GOES ACCORDING TO PLAN...THAT WILL TAKE CARE OF
OUR REMAINING FCST ZONES WHERE A FREEZE HAS NOT YET OCCURRED THIS
AUTUMN. THE UPPER RIDGE WILL START TO AMPLIFY OVER THE EAST DURING
MIDWEEK AND THAT WILL BUILD THE SURFACE HIGH AND RELOCATE IT TO OUR
NE FOR WEDNESDAY AND THURSDAY. EXPECT A SLOW WARMING TREND FOR THE
EARLY PART OF THE WEEK...THEN A SMALL JUMP UPWARD IN TEMPS FOR
MIDWEEK... BUT STILL BELOW NORMAL.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
AT KCLT...MVFR LEVEL CLOUDS CONTINUE TO SLOWLY LIFT AND SCATTER THIS
AFTN AS DRIER AIR WORKS IN FROM THE WEST...BUT UPPER LEVEL CLOUDS
WILL BE SLOWER TO CLEAR GIVEN THE SHARPENING UPPER JETLET OVER THE
APPALACHIANS. A FEW MESOSCALE MODELS PRODUCE LATE AFTERNOON SHOWERS
JUST EAST OF KCLT...BUT THIS APPEARS GENERALLY OVERDONE WITH MOST OF
THE FORCING AND LINGERING INSTABILITY EAST OF THE AREA. LIGHT WSW
WINDS SHOULD QUICKLY TOGGLE NW THIS AFTERNOON AND VEER TOWARD NRLY
OVERNIGHT. ALTHOUGH THE GROUND REMAINS MOIST AND SHALLOW FOG MAY
BECOME A CONCERN...NRLY MIXING OVERNIGHT SHOULD LARGELY PRECLUDE
RESTRICTIONS.
ELSEWHERE...LITTLE MORE THAN FEW TO SCT HIGH CLOUDS ARE EXPECTED
ACROSS THE TERMINAL FORECAST AREA GOING FORWARD. WINDS WILL CONTINUE
TO VEER NW THEN NRLY TONIGHT AS HIGH PRESSURE APPROACHES FROM THE
WEST. OCCASIONAL LOW END GUSTS ARE EXPECTED AT KAVL AS COLD
ADVECTION INCREASES BEHIND THE DEPARTING FRONT. PATCHY FOG WILL BE
POSSIBLE IN SHELTERED AREAS GIVEN THE MOIST GROUND...BUT MIXING ON
NRLY FLOW SHOULD LARGELY PRECLUDE RESTRICTIONS.
OUTLOOK...DRY HIGH PRESSURE WILL KEEP CONDITIONS VFR THROUGH SAT. A
SECONDARY COLD FRONT COULD BRING SCATTERED SHOWERS MAINLY TO THE
MOUNTAINS SAT NIGHT INTO EARLY SUNDAY...WITH SOME HIGH ELEVATION
SNOW POSSIBLE ALONG THE HIGHEST PEAKS...BUT WITH SMALL CHANCES OF
ANY RESTRICTIONS DOWN AT KAVL. DRY HIGH PRES WILL RETURN THROUGH
EARLY NEXT WEEK.
CONFIDENCE TABLE...
19-01Z 01-07Z 07-13Z 13-18Z
KCLT HIGH 83% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...HG
SHORT TERM...ARK
LONG TERM...ARK
AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
126 PM EST THU NOV 19 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST TONIGHT
THROUGH THE EARLY PART OF THE WEEKEND. A VIGOROUS COLD FRONT WILL
CROSS THE AREA FROM THE WEST SATURDAY NIGHT INTO SUNDAY...USHERING
IN THE COOLEST AIR OF THE SEASON SO FAR. DRY HIGH PRESSURE WILL THEN
RETURN FROM THE WEST EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 110 PM EST...A SURFACE COLD FRONT IS MAKING STEADY EASTWARD
PROGRESS ACROSS THE FORECAST AREA THIS AFTERNOON. THE HIGHER LEVEL
CLOUDS...HOWEVER...HAVE BEEN SLOW TO CLEAR AS AN UPPER JETLET MOVING
ACROSS THE APPALACHIANS CONTINUES TO SHARPEN UP THE UPPER LEVEL
DIVERGENCE OVER THE PIEDMONT. THIS WEAK UPPER SUPPORT WILL BE
COINCIDENT WITH A PASSING 500 MB SHORTWAVE LATE TODAY. PROFILES ARE
BECOMING INCREASINGLY DRY WITH THE FROPA...AND THE MESOSCALE MODELS
GENERALLY KEEP ANY RESULTANT SHOWERS JUST EAST OF THE FORECAST AREA.
THE LATEST HRRR DOES PRODUCE SOME ISOLD SHOWER ACTIVITY ALONG/EAST
OF THE INTERSTATE 77 CORRIDOR LATE DAY SO SLIGHT CHANCES WILL BE
RETAINED IN FAR EASTERN PARTS.
OTHERWISE...NW DOWNSLOPING FLOW ALONG WITH 850 MB COLD ADVECTION
WILL PICK UP TONIGHT AS SURFACE HIGH PRESSURE BUILDS IN FROM THE
WEST. SOME SHALLOW MOISTURE MAY LINGER ALONG THE SPINE OF THE SRN
APPALACHIANS BUT WITH LITTLE MORE THAN CLOUDS EXPECTED IN NW UPSLOPE
FLOW AREAS. THE PRES GRADIENT WILL BE RELATIVELY TIGHT TONIGHT AS
THE SURFACE HIGH BUILDS FROM THE MID MS VALLEY TO THE CENTRAL
APPALACHIANS...WHICH SHOULD KEEP MOST FOG PROBLEMS AT BAY DESPITE
THE MOIST GROUND. ANOTHER WEAK SHORTWAVE WILL PASS OVERNIGHT IN THE
INCREASINGLY ZONAL FLOW ALOFT...BUT WITH LITTLE TO NO DEEP MOISTURE
LEFT.
SOME BROAD CYCLONIC CURVATURE WILL DEVELOP IN THE FLOW ON FRIDAY AS
HEIGHTS FALL FROM THE ROCKIES INTO THE PLAINS. DOWNSLOPING WILL
CONTINUE AT LOW LEVELS...BUT 850 MB TEMPS SHOULD BE ABOUT 5 DEGREES
C COOLER BY FRI AFTN COMPARED TO TODAY...WITH MAXES ABOUT 10 DEGREES
LESS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 255 AM THU...GUIDANCE IN OVERALL AGREEMENT...BUT SOME
DISCREPANCIES TO DEVELOP BY THE END OF THE PERIOD. ZONAL FLOW OVER
THE AREA FRI BECOMES MORE AMPLIFIED SAT AS A SHORT WAVE MOVES ACROSS
THE NRN PLAINS INTO THE GREAT LAKES. THE WAVE MOVES INTO SRN QUEBEC
SAT NITE AS A WEAKER WAVE DROPS INTO THE MID MS VALLEY. AT THE
SFC...HIGH PRESSURE WILL BUILDS INTO THE AREA FRI AND SAT. A COLD
FRONT ASSOCIATED WITH THE AFORE MENTIONED SHORT WAVE MOVES TOWARD
THE ARE SAT AND ACROSS THE AREA SAT NITE. THERE WILL BE SOME LOW
LEVEL MOISTURE MOVING INTO THE MTNS AND W TO NW UPSLOPE FLOW WHICH
WILL LEAD TO A CHC OF SHOWERS. TEMPS DROP RAPIDLY BEHIND THE FRONT
AND COULD ALLOW THE RAIN TO CHANGE TO SNOW AT THE HIGHER ELEVATIONS.
HOWEVER...ANY PRECIP WOULD BE VERY LIGHT AND NO ACCUMS ARE EXPECTED.
ONE COMPLICATING FACTOR IS THE GUIDANCE IS DEVELOPING A LOW PRESSURE
NEAR FL ALONG THE COLD FRONT THAT CROSSED THE AREA THU. THIS LOW
MOVES UP THE ATLANTIC COAST AND BRINGS MOISTURE INTO THE AREA. THE
GUIDANCE AGREES THAT CLOUDS WILL INCREASE...BUT DIFFERS GREATLY ON
THE LOCATION AND AMOUNT OF ANY RESULTING PRECIP. THEREFORE...HAVE
GONE WITH MORE CLOUDS...BUT KEPT THE FCST DRY. NEAR NORMAL HIGHS FRI
DROP TO AROUND 5 DEGREES BELOW NORMAL SAT. LOWS A LITTLE BELOW
NORMAL FRI NITE DROP A COUPLE OF DEGREES...BUT ARE WARMER THAN THE
PREVIOUS FCST DUE TO THE INCREASED CLOUDS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 125 PM THURSDAY...WE APPRECIATE WHAT LOOKS TO BE A QUIET AND
DRY PERIOD IN THE RUN UP TO THANKSGIVING. THE AXIS OF AN UPPER TROF
SHOULD SWING EASTWARD ACROSS THE FCST AREA SUNDAY NIGHT WITH LITTLE
FANFARE. IN ITS WAKE...A FLAT UPPER RIDGE WILL BUILD IN AND CARRY
SURFACE HIGH PRESSURE ACROSS THE REGION MONDAY NIGHT AND TUESDAY. IF
THERE IS A MINOR PROBLEM...IT MIGHT BE LOW TEMPS SUNDAY NIGHT/EARLY
MONDAY MORNING. MODEL GUIDANCE SHOWS SUB-FREEZING TEMPS BY SUNRISE
MONDAY...SO IF ALL GOES ACCORDING TO PLAN...THAT WILL TAKE CARE OF
OUR REMAINING FCST ZONES WHERE A FREEZE HAS NOT YET OCCURRED THIS
AUTUMN. THE UPPER RIDGE WILL START TO AMPLIFY OVER THE EAST DURING
MIDWEEK AND THAT WILL BUILD THE SURFACE HIGH AND RELOCATE IT TO OUR
NE FOR WEDNESDAY AND THURSDAY. EXPECT A SLOW WARMING TREND FOR THE
EARLY PART OF THE WEEK...THEN A SMALL JUMP UPWARD IN TEMPS FOR
MIDWEEK... BUT STILL BELOW NORMAL.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
AT KCLT...MVFR LEVEL CLOUDS CONTINUE TO LIFT AND SCATTER AT ISSUANCE
TIME...BUT UPPER LEVEL CLOUDS WILL BE SLOW TO CLEAR GIVEN THE
SHARPENING UPPER JETLET OVER THE APPALACHIANS. A FEW MESOSCALE
MODELS PRODUCE LATE AFTERNOON SHOWERS JUST EAST OF KCLT...BUT THIS
APPEARS GENERALLY OVERDONE WITH MOST OF THE FORCING AND LINGERING
INSTABILITY EAST OF THE VICINITY. LIGHT WSW WINDS SHOULD QUICKLY
TOGGLE NW THIS AFTERNOON AND VEER TOWARD NRLY OVERNIGHT. ALTHOUGH
THE GROUND REMAINS MOIST AND SHALLOW FOG MAY BECOME A CONCERN...NRLY
MIXING OVERNIGHT SHOULD LARGELY PRECLUDE RESTRICTIONS.
ELSEWHERE...LITTLE MORE THAN FEW TO SCT HIGH CLOUDS ARE EXPECTED
ACROSS THE TERMINAL FORECAST AREA GOING FORWARD. WINDS WILL CONTINUE
TO VEER NW THEN NRLY TONIGHT AS HIGH PRESSURE APPROACHES FROM THE
WEST. OCCASIONAL LOW END GUSTS ARE EXPECTED AT KAVL AS COLD
ADVECTION INCREASES BEHIND THE DEPARTING FRONT. PATCHY FOG WILL BE
POSSIBLE IN SHELTERED AREAS GIVEN THE MOIST GROUND...BUT MIXING ON
NRLY FLOW SHOULD LARGELY PRECLUDE RESTRICTIONS.
OUTLOOK...DRY HIGH PRESSURE WILL KEEP CONDITIONS VFR THROUGH SAT. A
SECONDARY COLD FRONT COULD BRING SCATTERED SHOWERS MAINLY TO THE
MOUNTAINS SAT NIGHT INTO EARLY SUNDAY...WITH SOME HIGH ELEVATION
SNOW POSSIBLE ALONG THE HIGHEST PEAKS...BUT WITH SMALL CHANCES OF
ANY RESTRICTIONS DOWN AT KAVL. DRY HIGH PRES WILL RETURN THROUGH
EARLY NEXT WEEK.
CONFIDENCE TABLE...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT HIGH 87% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 97% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...HG
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...HG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1229 AM EST THU NOV 19 2015
.SYNOPSIS...
WIDESPREAD RAINFALL IS EXPECTED TONIGHT AND TOMORROW MORNING AHEAD
OF A COLD FRONT. AFTER THE FRONTAL PASSAGE TOMORROW MORNING...COOL
AND DRY HIGH PRESSURE WILL MOVE BACK OVER THE REGION AND REMAIN IN
PLACE THROUGH SATURDAY. ANOTHER COLD FRONT WILL CROSS THE AREA ON
SUNDAY...WITH EVEN COLDER HIGH PRESSURE SPREADING OVER THE REGION IN
ITS WAKE.
&&
.NEAR TERM /THROUGH TODAY/...
0515 UTC UPDATE...POPS AND QPF HAVE BEEN ADJUSTED PER RADAR TRENDS.
WINDS WERE UDPATED WITH A BLEND OF THE LATEST NAM AND ADJMAV
GUIDANCE. THE TORNADO WATCH HAD BEEN CANCELLED FOR OUR GA AND SC
COUNTEID PER COORDINATION WITH SPC.
915 PM UPDATE...PREFRONTAL BAND OF RAIN NOW COVERS MOST OF THE CWFA
WEST OF I-77. EMBEDDED WITHIN ARE A FEW LINEARLY ORIENTED CONVECTIVE
BANDS THOUGH NOT EVEN LIGHTNING HAS BEEN DETECTED IN OUR AREA OVER
THE PAST HOUR OR SO. INSTABILITY IS PROVING HARD TO COME BY SO
FAR. RAP HAS BACKED OFF/DELAYED EARLIER PROGS OF INCREASING SBCAPE
OVER OUR LOWER PIEDMONT AREAS...NOW SUGGESTING THEY WON/T SEE MUCH
FORM UNTIL WELL AFTER MIDNIGHT. BACK EDGE OF THE PRECIP SHIELD
LOOKS LIKELY TO WORK INTO OUR WRNMOST ZONES IN THE NEXT COUPLE
HOURS. A PENCIL-THIN BAND OF ACTIVITY IS ORIENTED RIGHT ALONG
THE SFC FRONT OVER THE CUMBERLAND PLATEAU...AND DESPITE STRONG
UPPER FORCING THIS DOES NOT STAND MUCH CHANCE OF STRENGTHENING
AS IT ENCOUNTERS THE MTNS. PRESENT PLANS ARE TO KEEP THE TORNADO
WATCH IN EFFECT UNTIL 300 A.M. BUT THE WINDOW OF OPPORTUNITY IS
CURRENTLY SHRINKING...IT WOULD APPEAR.
AS FAR AS HYDRO...MOST SITES AWAY FROM UPSLOPE AREAS ARE REPORTING
RATES OF 0.15 TO 0.5 INCHES PER HOUR IN GENERAL...WITH SIGNIFICANT
ENHANCEMENT COMING AS CONVECTIVE FEATURES PASS THROUGH. RATES/ACCUMS
REPORTED BY MESONET GAGES ALONG THE ESCARPMENT OF COURSE ARE
SUBSTANTIALLY HIGHER. I REVISED QPF AND THE STORM TOTAL PRODUCT WITH
EXTRA WEIGHT ON THE HIGH-RES GUIDANCE WHICH AS A WHOLE REFLECTS A
SIMILAR DISTRIBUTION OF PRECIP. WE ARE SEEING SOME LOCALIZED FLOOD
ISSUES IN THE USUAL AREAS IN THE FOOTHILLS. THE LATER POSSIBILITY
OF CONVECTION HOWEVER DOES STILL IMPLY SOME LONGER-DURATION TYPE
ISSUES MAY RESULT OVER PARTS OF THE UPSTATE.
AS OF 235 PM...MID AFTERNOON KGSP WSR-88D VWP INDICATES 3-6 KFT
WINDS WERE FROM THE SE BETWEEN 40-45 KTS. NEAR TERM MODELS INDICATE
THAT MOISTURE SOURCED FROM THE GULF OF MEXICO AND THE WESTERN
ATLANTIC WILL LIFT ACROSS NE GA AND THE WESTERN CAROLINAS...PW
VALUES WILL RISE TO NEAR 2 INCHES BY 23Z. THE COMBINATION OF
STRONG UPSLOPE FLOW AND DEEP MOISTURE WILL SUPPORT A SOLID 4 TO
6 HOURS OF ADDITIONAL UPSLOPE MODERATE RAINFALL ALONG THE EAST
FACING SLOPES BEFORE THE PRE FRONTAL CONVECTIVE BAND ARRIVES. AS
OF 230 PM...OBSERVED RAINFALL TOTALS RANGED FROM 3.2 INCHES NEAR
LAKE TOXAWAY TO 1 TO 1.5 INCHES ACROSS THE SALUDA GRADE.
THIS EVENING...12Z GFS INDICATES A LARGE FIELD OF Q-VECTOR
CONVERGENCE WILL SPREAD ACROSS THE FORECAST AREA LATE THIS AFTERNOON
AND EVENING. AT H3...THE RIGHT ENTRANCE REGION OF A SOUTH-NORTH
160KT JET WILL SLIDE OVER THE CWA...EXITING AFTER 3Z.
CAMS INDICATE THAT A WIDE BAND PRE FRONTAL BAND OF CONVECTION WILL
SLIDE EAST ACROSS EASTERN TN/NRN GA BETWEEN 23Z TO 1Z. NAM FORECAST
SOUNDINGS ALONG AND AHEAD OF THE CONVECTIVE BAND INDICATES 0-1
KM SHEAR OVER 400 M2/S2...AND 300-500 J/KG OF SB CAPE...AND 0-1
KM EHI AS HIGH AS 1.25 M2/S2 ACROSS THE LAKELANDS. INSTABILITY
PARAMETERS RISE AFTER 0Z THURS. IN ADDITION TO MODERATE TO HEAVY
RAIN SHOWERS...I WILL INCREASE THE MENTION OF TSRA ACROSS THE
UPPER SAVANNAH RIVER VALLEY ACROSS THE PIEDMONT. IN AGREEMENT WITH
UPDATED DY1 CONVECTIVE OUTLOOK...I WILL ADD A MENTION OF SVR TSRA
ACROSS THE UPPER SAVANNAH RIVER VALLEY IN THE HWO.
SIGNIFICANT SYNOPTIC SCALE DYNAMICS...STRONG UPSLOPE FLOW...AND
A PASSING WINDOW FOR DEEP CONVECTION SHOULD RESULT IN HEAVY
RAINFALL RATES THIS EVENING AND INTO EARLY THURSDAY MORNING. IT
IS POSSIBLE THAT RAINFALL RATES COULD EXCEED THE 1-3 HR FFG ACROSS
THE MTNS...FOOTHILLS...THE WESTERN UPSTATE...AND EXTREME NE GA. IN
ADDITION...A COUPLE OF OPERATIONAL FORECASTS ALONG MAIN STEM RIVERS
INDICATE STAGES ABOVE FLOOD STAGE. I WILL CONTINUE TO HIGHLIGHT
THE RAINFALL THREAT WITH A FLASH FLOOD WATCH INTO THURSDAY MORNING.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
AS OF 215 PM EST...BRIEF AND SHALLOW NW FLOW MOISTURE WILL QUICKLY
DISSIPATE ACROSS THE NORTHERN MOUNTAINS THURSDAY EVENING.
OTHERWISE...AN UPPER CYCLONE OVER THE WESTERN GREAT LAKES WILL LIFT
NORTHEAST INTO CANADA THURSDAY NIGHT THROUGH FRIDAY LEAVING
RELATIVELY ZONAL FLOW IN PLACE OVER THE SOUTHEAST. UNDER THE ZONAL
FLOW...SPRAWLING SURFACE HIGH PRESSURE WILL BUILD EASTWARD FROM THE
MID MS RIVER VALLEY TO THE APPALACHIANS THROUGH LATE WEEK. TEMPS
CLOSE TO CLIMO FRI WILL FALL BELOW CLIMO SATURDAY WITH NE WINDS
AROUND THE SFC HIGH. MEANWHILE...A TROUGH WILL DIG FROM THE NORTHERN
PLAINS INTO THE MIDWEST FRIDAY NIGHT THROUGH SATURDAY. THIS SYSTEM
WILL PUSH A REINFORCING COLD FRONT AND A NARROW BAND OF MOISTURE TO
THE SPINE OF THE SOUTHERN APPALACHIANS BY LATE DAY ON SATURDAY. VERY
LITTLE MOISTURE RECOVERY IS EXPECTED AHEAD OF THE FRONTAL
SYSTEM...WITH JUST LATE DAY SLIGHT CHANCES OF SHOWERS IN THE WESTERN
MOUNTAINS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 215 PM WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
SUNDAY WITH STEEP UPPER TROFFING CENTERED OVER THE GREAT LAKES AND
UPPER RIDGING OVER THE WESTERN CONUS. THE MODELS DIFFER WRT THE
PROGRESSION OF THE TROF OVER THE NEXT 24 TO 48 HRS. THE LATEST 12Z
GFS AMPLIFIES THE SYSTEM AND MOVES THE TROF AXIS RIGHT OVER THE CWFA
LATE SUN/EARLY MON AND THEN QUICKLY MOVES THE SYSTEM OFFSHORE. THE
PATTERN FLATTENS OUT IN THE TROFS WAKE WITH HEIGHTS SLOWLY RISING
FOR THE REMAINDER OF THE PERIOD. THE ECMWF...ON THE OTHER
HAND...LIFTS THE TROF NE OF THE REGION ON SUN WHILE SIMULTANEOUSLY
DEVELOPING A POTENT SHORTWAVE ON THE BACKSIDE OF THE MAIN TROF. THIS
SHORTWAVE QUICKLY APPROACHES THE FCST AREA FROM THE WEST EARLY MON
AND MOVES OVERHEAD LATER THAT DAY. THE REMAINDER OF THE FCST IS
SIMILAR TO THE GFS WITH HEIGHTS RISING AS UPPER RIDGING MOVES BACK
OVER THE REGION THRU MIDWEEK.
AT THE SFC...A DRY COLD FRONT WILL BE MOVING INTO THE FCST AREA BY
THE START OF THE PERIOD AS ITS PARENT LOW PASSES OVER THE EASTERN
GREAT LAKES. THE FRONT IS EXPECTED TO MOVE THRU THE AREA QUICKLY
WITH COLD AND DRY HIGH PRESSURE OVERSPREADING THE REGION AGAIN IN
ITS WAKE. THE GFS HAS THE HIGH LINGERING OVER THE REGION THRU DAY 7
WITH IT SHIFTING NE TOWARDS NEW ENGLAND...HOWEVER THE ECMWF TRIES TO
SPIN UP A LOW OFF THE EAST COAST OF FLORIDA EARLY MON AND MOVE THE
SYSTEM NE OVER THE NEXT COUPLE OF DAYS. AT THE PRESENT TIME...IT
REMAINS FAR ENOUGH OFFSHORE THAT IT DOES NOT DIRECTLY IMPACT OUR
SENSIBLE WX. AS FOR THE SENSIBLE FCST...I ONLY KEEP A SLIGHT CHANCE
POP ALONG THE NC/TENN BORDER FOR EARLY SUN MORNING AS THE FRONT
MOVES THRU WITH DRY CONDITIONS AFTER THAT. THE TEMPS/THICKNESSES LOOK
COLD ENOUGH TO SUPPORT LIGHT SNOW SHOWERS IF PRECIP DOES
DEVELOP...BUT IT WOULD NOT AMOUNT TO MUCH. SIGNIFICANT CAA WILL KEEP
TEMPS WELL BELOW NORMAL THRU THE PERIOD WITH SOME WARMING ON TUES
AND WED AS THICKNESSES RECOVER.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AT KCLT...PRECIPITTAION AND ASSOCIATED RESTRICTIONS WILL CONTINUE
UNTIL EARLY MORNING. THEN AS THE COLD FRONT MOVES PAST...IMPROVEMENT
WILL OCCUR DURING THE MORNIGN. VFR WILL FOLLOW. WIDNS WILL VEER FROM
SE TO SW IN HTE MORNING...THEN TO NW IN THE AFTERNOON. GSUTS WILL
ACTUALLY DECREASE BY AFTERNOON.
ELSEWHERE...ALTHGOUHT PRECIPITIATIION WILL DECREASE OVERNIGHT...
RESTRICTIONS WILL PERSIST UNTIL DAWN...UNTIL DRIER AIR CAN ARRIVE
BEHIND THE DEPARTING COLD FRONT. WINDS WILL VEER FROM SE TO SW IN
HTE FOOTHILSL BY DAWN...AND FROM SE TO NW AT KAVL. FOOTHILLS WINDS
VEER NW BY AFTERNOON...WITH GUSTS DECREASING.
OUTLOOK...DRY HIGH PRESSURE WILL BRING VFR CONDITIONS FOR THURSDAY
NIGHT AND FRIDAY. A SECONDARY COLD FRONT COULD BRING SOME LIGHT SNOW
AND MINOR VSBY RESTRICTIONS TO THE HIGHER NC MTNS SATURDAY NIGHT.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-00Z
KCLT HIGH 100% LOW 55% MED 62% HIGH 94%
KGSP MED 69% MED 75% HIGH 81% MED 78%
KAVL HIGH 87% LOW 41% HIGH 100% MED 66%
KHKY HIGH 100% HIGH 94% HIGH 81% MED 72%
KGMU MED 69% MED 61% HIGH 81% HIGH 83%
KAND HIGH 94% HIGH 100% MED 75% HIGH 83%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLASH FLOOD WATCH UNTIL 10 AM EST THIS MORNING FOR GAZ010-017-
018-026-028-029.
NC...FLASH FLOOD WATCH UNTIL 10 AM EST THIS MORNING FOR NCZ033-
048>053-058-059-062>065-501>510.
SC...FLASH FLOOD WATCH UNTIL 10 AM EST THIS MORNING FOR SCZ001>007-
010-011.
&&
$$
SYNOPSIS...JPT
NEAR TERM...JAT/NED/WIMBERLEY
SHORT TERM...HG
LONG TERM...JPT
AVIATION...JAT
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
327 PM CST THU NOV 19 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 325 PM CST THU NOV 19 2015
STRONG WINDS PEAKED EAST LATE THIS MORNING AND STARTED TO DROP OFF A
BIT BEFORE NOON. THE EXITING OF A WAVE TO THE NORTHEAST RESULTED IN A
DROPOFF OF LOW LEVEL WINDS AND EVEN A LITTLE WARMING AT 5K FEET...
APPARENTLY PEGGED CORRECTLY BY THE RAP AS SEEN ON BUFKIT WITH THE
WINDS...TO CUT DOWN ON THE MIXED LAYER. ADVISORY WILL BE CONTINUED
TO ORIGINAL EXPIRATION EAST BUT WILL PLAN ON CANCELING A BIT
EARLIER SOUTHWEST. WINDS WILL THEN DROP OFF QUICKLY EARLY THIS
EVENING. SKIES WILL BE GENERALLY CLEAR THROUGH THIS EVENING THOUGH
AN INCREASE IN HIGH AND SOME MID CLOUDS WILL START BEFORE MIDNIGHT
FROM THE SOUTHWEST. TEMPERATURES WILL COOL INTO THE LOWER TO
MIDDLE 20S THIS EVENING WITH THE COOLING RATE SLOWING SOUTHWEST
LATE EVENING AS CLOUDS START TO INCREASE THERE.
LOOKING AT A FAIRLY SIGNIFICANT SNOW EVENT ACROSS THE AREA ON
FRIDAY. ON THE LARGE SCALE...A SERIES OF JET STREAKS WILL AID IN
THE DEVELOPMENT AND ENHANCEMENT OF HEAVY SNOW BAND THAT IS EXPECTED
TO DEVELOP ACROSS THE AREA. AS OF 12Z...THE MAIN JET AXIS EXTENDS
FROM THE PACIFIC NW DOWN THROUGH THE CENTRAL PORTION OF THE US.
ACROSS THE UPPER MIDWEST...THERE IS A JET STREAK ACROSS SOUTHERN
MINNESOTA INTO SOUTHERN WISCONSIN WITH THE RIGHT ENTRANCE REGION
ACROSS MUCH OF THE FORECAST AREA. EXPECT THIS JET STREAK TO AID IN
THE DEVELOPMENT OF THE BAND AS THE INTENSIFYING WAVE MOVES INTO THE
AREA.
MODEL SOUNDINGS SUGGEST A FAIR AMOUNT OF DRY AIR THAT HAS TO BE
OVERCOME INITIALLY IN THE NEAR SURFACE LAYER. EXPECT ATMOSPHERE TO
SATURATE RELATIVELY QUICKLY...WITH SNOW BEGINNING TO FALL ACROSS
SOUTH CENTRAL SOUTH DAKOTA BETWEEN 9-12Z. INITIALLY SNOW SHOULD BE
FAIRLY LIGHT...BUT SHOULD INCREASE IN INTENSITY AS STRONG 700 MB
FRONTOGENTIC FORCING MOVES INTO THE AREA. WITH SNOWFALL BEGINNING
FAIRLY LIGHT...WILL LIKELY SEE SOME MELTING AS THE SURFACE LAYER IS
STILL NEAR 40 DEGREES. BY 9 AM OR SO...IT APPEARS THAT THE
ATMOSPHERE BECOMES WEAKLY UNSTABLE ABOVE THE FRONTOGENETIC BAND. IN
ADDITION...AS THE ATMOSPHERIC COLUMN COOLS...DENDRITIC LAYER
INCREASES IN DEPTH. WITH WEAK WINDS THROUGH THE ATMOSPHERE...HAVE
THE POTENTIAL OF SEEING SNOWFALL RATIOS INCREASE AS THE DENDRITIC
DEPTH INCREASES. WITH THE INSTABILTY...COULD SEE SNOWFALL RATES
INCREASE WITHIN THE MAIN BAND TO 1"+/HOUR. HAVE RAISED SNOWFALL
AMOUNTS WITHIN THE BAND...BUT HIGHER AMOUNTS ARE POSSIBLE ESPECIALLY
FROM YANKTON TO SPENCER IA AND AREAS SOUTH TOWARDS STORM LAKE.
ON THE NORTH SIDE OF THE BAND...IT IS MUCH MORE MURKY WHERE THE
NORTHERN EDGE OF THE BAND WILL SET UP. GIVEN THE UNCERTAINTY...WILL
LEAVE THE WATCH IN PLACE FOR NOW.
AS FOR TEMPERATURES...GUIDANCE IS POOR GIVEN THE AMOUNT OF WARMING
THAT IS ANTICIPATED IN THE MODELS DURING THE PRECIPITATION EVENT.
HAVE STARTED WITH PREVIOUS FORECAST...AND MADE ONLY MINOR TWEAKS TO
THE HIGHS AT THIS POINT.
WILL BE A STRUGGLE TO WARM SIGNIFICANTLY ON SATURDAY WITH SNOWPACK
LINGERING ACROSS THE SOUTH. 925 HPA TEMPS WARM TO -5 TO -7C
THROUGHOUT THE DAY...PROMOTING HIGHS IN THE 20S. SUBTLE WARM FRONT
IS EXPECTED TO MOVE THROUGH THE AREA SATURDAY NIGHT. HAVE NOT MADE
CHANGES TO THE FORECAST SATURDAY NIGHT WITH THE FORCUS ON THE SNOW
BAND.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 325 PM CST THU NOV 19 2015
THE SUNDAY START OF DRY AND WARMING WEATHER WILL CONTINUE THROUGH AT
LEAST TUESDAY WITH UPPER RIDGING. THE WARMING FOR NOW LOOKS TO BE
MODIFIED BY SOME DELAY IN LOW LEVEL WARMING...LIKELY REMAINING SNOW
COVER ESPECIALLY SOUTHEAST...AND OF COURSE THE LOWERING LATE
NOVEMBER SUN ANGLE...SO LOOK FOR DAYTIME HIGHS NOT TO GET TOO FAR
INTO THE 40S FOR NOW. WEDNESDAY STILL LOOKS RELATIVELY MILD...BUT A
SOUTHERLY FETCH OF LOW LEVEL MOISTURE MAY AGAIN COME INTO PLAY AND
BRING A CHANCE OF RAIN OR DRIZZLE EAST. THANKSGIVING DAY LOOKS LIKE
COOLER WITH SOME CHANCE OF RAIN AND SNOW...IN SLIGHTLY DIFFERENT
WAYS BOTH THE GFS AND EC SHOW THIS. THE EC SHOWS A MUCH DEEPER
SYSTEM TO THE SOUTHWEST AS THANKSGIVING GETS HERE...BUT SO DEEP IT
IS SHEARED OFF FROM COMING UP BY THE NORTHERN WAVE...SO AT THIS TIME
IT DOES NOT LOOK LIKE A MAJOR HOLIDAY SYSTEM...BUT OF COURSE THAT
CAN CHANGE WHEN LOOKING A WEEK AHEAD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1134 AM CST THU NOV 19 2015
VFR THROUGH 20/12Z. SURFACE GUSTS 25-40 KNOTS FROM THE W/NW
DECREASING FROM THE WEST 19/21Z-20/00Z. AFTER 20/12Z INCREASING
CEILINGS 1-3K AND VISIBILITIES 3-5SM/S- SOUTHWEST OF HON/FSD/SLB
LINE...WITH AREAS OF VISIBILITIES BELOW 3SM/S DEVELOPING THIS
AREA AFTER 14Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER STORM WARNING FROM 6 AM TO 9 PM CST FRIDAY FOR SDZ068>071.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR SDZ038>040-050-
052>071.
WINTER STORM WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR SDZ065>067.
WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST FRIDAY FOR SDZ050-
063-064.
MN...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ071-072-080-081-
089-090-097-098.
IA...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ001>003-012>014-
020>022-031-032.
WINTER STORM WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR IAZ001>003.
WINTER STORM WARNING FROM 9 AM FRIDAY TO MIDNIGHT CST FRIDAY
NIGHT FOR IAZ012>014-020>022-031-032.
NE...WINTER STORM WARNING FROM 6 AM TO 9 PM CST FRIDAY FOR NEZ013-014.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ013-014.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1145 PM CST WED NOV 18 2015
.UPDATE...
UPDATED TO INCLUDE 06Z AVIATION DISCUSSION BELOW.
&&
.PREV DISCUSSION... /ISSUED 845 PM CST WED NOV 18 2015/
DISCUSSION...
CLEAR SKIES PREVAIL ACROSS THE MIDSOUTH. A WEAK COLD FRONT IS
APPROACHING FROM THE NORTHWEST WHILE WEAK HIGH PRESSURE SITS OVER
THE LOWER MISSISSIPPI VALLEY. THE PRESSURE GRADIENT IS WEAK ACROSS
NORTHEAST MISSISSIPPI WHERE SKIES CLEARED OUT LATE. FOG IS
ALREADY DEVELOPING ACROSS MONROE COUNTY AND POINTS SOUTHEAST.
LATEST HRRR SHOWS FOG SPREADING ACROSS NORTHEAST MISSISSIPPI
OVERNIGHT. ADDED AREAS OF FOG TO THE FORECAST AND WILL NEED TO
MONITOR FOR A POSSIBLE DENSE FOG ADVISORY. THE PRESSURE GRADIENT
IS A LITTLE STRONGER OVER THE REMAINDER OF THE AREA...THANKS TO
THE APPROACHING FRONT...WHICH SHOULD HELP KEEP A LIGHT SOUTHWEST
WIND GOING AND LIMIT FOG POTENTIAL. OTRW FORECAST IS ON TRACK.
UPDATE ALREADY OUT.
SJM
&&
.PREV DISCUSSION... /ISSUED 259 PM CST WED NOV 18 2015/
SKIES REMAIN CLOUDY OVER EASTERN SECTIONS OF THE FORECAST AREA
WITH MOSTLY SUNNY SKIES ELSEWHERE. TEMPERATURES THIS AFTERNOON
RANGE FROM THE MID 50S TO MID 60S. THE CLOUDS OVER EASTERN
SECTIONS OF THE FORECAST AREA WILL MOVE OUT THIS EVENING LEAVING
MOSTLY CLEAR TONIGHT. WINDS SHOULD NOT GO CALM OVERNIGHT SO IT
DOES NOT APPEAR THAT MUCH FOG WILL DEVELOP OVERNIGHT. TEMPERATURES
WILL COOL DOWN TO NEAR NORMAL LEVELS WITH LOWS THURSDAY MORNING IN
THE LOW TO MID 40S.
A SECOND COLD FRONT WILL PUSH THROUGH THE REGION ON THURSDAY. THE
AIR AHEAD OF THIS FRONT IS DRIER THAN THE FIRST FRONT SO NO RAIN
IS EXPECTED WITH THIS FRONT. TEMPERATURES WILL BE FAIRLY MILD
FOR MID-NOVEMBER WITH HIGHS IN THE UPPER 50S TO MID 60S. HIGH
PRESSURE WILL SETTLE INTO THE REGION THURSDAY NIGHT BRINGING
COLDER AIR INTO THE FORECAST AREA. LOWS FRIDAY MORNING WILL RANGE
FROM THE MID 30S TO LOWER 40S. HIGH PRESSURE WILL REMAIN NEAR THE
REGION ON FRIDAY WITH DRY WEATHER AND NEAR NORMAL TEMPERATURES.
BY FRIDAY NIGHT...ANOTHER COLD FRONT WILL MOVE INTO THE REGION BY
EARLY SATURDAY MORNING. THERE WILL BE SOME MOISTURE AHEAD OF THE
FRONT SO THERE COULD BE SOME SHOWERS LATE FRIDAY NIGHT OVER
NORTHWEST SECTIONS OF THE FORECAST AREA. AS THE FRONT MOVES
THROUGH THE REMAINDER OF THE FORECAST AREA ON SATURDAY MORE
SHOWERS WILL BE POSSIBLE MAINLY OVER NORTHERN SECTIONS.
TEMPERATURES WILL TURN COLDER BEHIND THE FRONT WITH HIGHS ON
SATURDAY IN THE UPPER 40S TO AROUND 60 DEGREES.
HIGH PRESSURE WILL BUILD INTO THE REGION SATURDAY NIGHT. THIS WILL
ALLOW TEMPERATURES TO DROP BELOW FREEZING OVER MUCH OF THE
FORECAST AREA SO THIS WILL LIKELY BE THE FIRST FREEZE FOR A LOT OF
THE AREA THAT DID NOT SEE BELOW FREEZING TEMPERATURES LAST
WEEKEND. HIGH PRESSURE WILL REMAIN OVER THE REGION ON SUNDAY
KEEPING THINGS UNSEASONABLY COOL WITH HIGHS MAINLY IN THE 40S.
SUNDAY NIGHT WILL BE ANOTHER CHILLY NIGHT WITH MOST LOCATIONS
SEEING TEMPERATURES NEAR OR BELOW FREEZING.
BY MONDAY...THE SURFACE HIGH WILL BE EAST OF THE REGION. THIS WILL
ALLOW WINDS TO SHIFT TO THE SOUTH AND BRING MILDER AIR INTO THE
FORECAST AREA. THIS WILL START A WARMING TREND WHICH WILL GO FROM
MONDAY THROUGH NEXT WEDNESDAY. A WEAK FRONTAL BOUNDARY WILL MOVE
INTO NORTHERN ARKANSAS NEXT WEDNESDAY WHICH COULD MEAN SOME RAIN
SHOWERS OVER WESTERN SECTIONS OF THE FORECAST AREA.
ARS
&&
.AVIATION...
06Z TAFS
VFR CONDITIONS WILL PREVAIL ACROSS THE AREA...EXCEPT AT TUP WHERE
DENSE FOG WILL BE AN ISSUE OVERNIGHT. LIFR/IFR VSBYS ARE EXPECTED
AS WINDS GO CALM. ELSEWHERE...WINDS SHOULD REMAIN FROM SOUTHWEST
AROUND 3 TO 5 KTS UNDER CLEAR SKIES.
WINDS WILL SHIFT NORTHWEST AND INCREASE TO AROUND 10 KTS AT ALL
SITES AFTER 19/18Z AS A DRY COLD FRONT MOVES THROUGH. WINDS WILL
RELAX TO 6 KTS OR LESS AFTER SUNDOWN.
AC3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR ALCORN-CALHOUN-
CHICKASAW-ITAWAMBA-LEE MS-MONROE-PONTOTOC-PRENTISS-TIPPAH-
TISHOMINGO-UNION.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1129 AM CST THU NOV 19 2015
.DISCUSSION...SEE AVIATION DISCUSSION BELOW FOR THE 18Z TAFS.
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD.
CIGS ARE EXPECTED TO DVLP TONIGHT...BUT SHOULD REMAIN ABV 3KFT.
BRIEF PATCHY LIGHT FOG IS ALSO POSSIBLE TOWARD EARLY FRI
MORNING...HOWEVER THE CLOUDS SHOULD HINDER FOG DVLPMNT AND WILL
NOT MENTION IN TAFS AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 856 AM CST THU NOV 19 2015/
DISCUSSION...QUIET WEATHER CONDITIONS WILL PERSIST TODAY AS WINDS
GRADUALLY VEER TO THE E AND SLOWLY ADVECT LOW LEVEL MOISTURE BACK
INTO S TX. HIGHS ARE EXPECTED TO BE A TAD WARMER THAN YESTERDAY`S
VALUES. OVERALL FCST LOOKS ON TRACK WITH NO MAJOR CHANGES AT THIS
TIME. WILL UPDATE ZONES TO REMOVE MENTION OF MORNING FOG.
PREV DISCUSSION... /ISSUED 538 AM CST THU NOV 19 2015/
DISCUSSION...SEE AVIATION SECTION FOR 12Z TAFS.
AVIATION...ALTHOUGH THE TEMP/DEWPOINT SPREADS ARE NEAR ZERO FOR
THE COASTAL PLAINS...FOG HAS BEEN SLOW TO FORM WITH ONLY SPOTTY
OCCURRENCES OVER THE PAST COUPLE OF HOURS. WINDS ARE 5-7 KNOTS
FROM THE NORTH WHICH MAY KEEP FOG FROM FORMING. WILL KEEP A
TEMPO GROUP FROM 12-14Z FOR VCT FOR FOG/MVFR VSBYS. THEN CLEAR
SKIES AND VFR CONDITIONS FOR MOST OF THE DAY TODAY. CLOUDS
AROUND 6 KFT OVER THE GULF WATERS EAST OF THE LOWER TEXAS COAST
SHOULD MOVE NORTHWARD LATE THIS AFTERNOON AND REACH THE SOUTHERN
PARTS OF THE COASTAL BEND/BRUSH COUNTRY. MOISTURE ADVECTION IN
THIS LAYER WILL INCREASE TONIGHT WITH BROKEN CLOUD DECK NEAR
5 KFT REACHING LRD AT 04Z AND AT CRP BY 08Z.
PREV DISCUSSION... /ISSUED 339 AM CST THU NOV 19 2015/
SHORT TERM (TODAY THROUGH FRIDAY)...LIGHT NORTHEAST WINDS AND
NEAR ZERO TEMP/DEWPOINT SPREAD WILL LEAD TO A BRIEF POTENTIAL FOR
FOG OVER THE COASTAL PLAINS EARLY THIS MORNING. FOG HAS BEEN
REPORTED AT PORT LAVACA IN THE PAST HOUR. ONLY MODEL INDICATING
A STRONG INDICATOR FOR FOG IS THE LATEST RAP MODEL. WILL HAVE TO
WATCH TRENDS TO SEE IF FOG BECOMES DENSE OVER THE NEXT COUPLE OF
HOURS.
OTHERWISE...ANOTHER BENIGN WEATHER DAY IS EXPECTED. SURFACE HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL BUILD EASTWARD INTO THE
MID MISSISSIPPI RIVER VALLEY TODAY. WINDS WILL INCREASE FROM THE
EAST-NORTHEAST LATER TODAY. HIGH TEMPERATURES WILL BE NEAR OR
SLIGHTLY WARMER THAN YESTERDAY.
LOW LEVEL FLOW WILL VEER TO EAST-SOUTHEAST LATER TONIGHT AS LOW
PRESSURE DEEPENS LEE OF THE CENTRAL ROCKIES. LOW CLOUDS ARE
EXPECTED TO RETURN ALONG THE RIO GRANDE INTO THE BRUSH COUNTRY
LATE TONIGHT. LOW LEVEL FLOW WILL BECOME SOUTHERLY FRIDAY WITH
MOISTURE STEADILY INCREASING WITH MOSTLY CLOUDY SKIES EXPECTED.
WEAK ISENTROPIC LIFT WILL LEAD TO A SLIGHT CHANCE OF LIGHT RAIN
OVER THE COASTAL WATERS INTO THE COASTAL BEND BY THE AFTERNOON.
WENT NEAR OR SLIGHTLY BELOW COOLER NAM GUIDANCE FOR HIGHS.
MARINE...EAST-NORTHEAST FLOW IS EXPECTED TO INCREASE BY THIS
AFTERNOON OVER THE OFFSHORE WATERS TO SCEC LEVELS AND REMAIN
AT THIS STRENGTH THROUGH THE NIGHT. SWELLS OF 4 TO 5 FEET WITH
PERIOD OF 8 SECONDS ALONG WITH EAST-NORTHEAST WINDS WILL KEEP
A MODERATE RISK OF RIP CURRENTS ALONG THE COAST.
LONG TERM (FRIDAY NIGHT THROUGH THANKSGIVING DAY)...CHANCES FOR
RAIN INCREASE OUT AHEAD OF A SIGNIFICANT COLD FRONT DUE TO MOVE
THROUGH SOUTH TEXAS SATURDAY MORNING. EXPECT SCATTERED
SHOWERS...WITH BETTER CHANCES OVER THE MIDDLE TEXAS COAST WHERE LOW
LEVEL MOISTURE WILL HAVE A BETTER CHANCE AT POOLING BEFORE FROPA.
HIGHS ON SATURDAY WILL OCCUR IMMEDIATELY BEFORE THE FRONT
PASSES...WITH TEMPERATURES FALLING QUICKLY BEHIND THE FRONT. WINDS
WILL ALSO PICK UP SUBSTANTIALLY BEHIND THE FRONT...WITH SMALL CRAFT
ADVISORY CONDITIONS EASILY MET FROM FROPA ALL THE WAY THROUGH EARLY
SUNDAY. CAA WILL KEEP TEMPERATURES IN THE 50S ON SUNDAY...AND
READINGS WILL DIP INTO THE 40S AWAY FROM THE COAST MONDAY MORNING AS
HIGH PRESSURE BUILDS INTO THE REGION.
HIGH PRESSURE WILL BEGIN TO SLIDE OFF TO THE EAST LATE
MONDAY...INITIATING RETURN FLOW ALONG THE COASTAL BEND. A FEATURE OF
INTEREST WILL BE MOISTURE FROM AN EASTERN PACIFIC TROPICAL
SYSTEM...AND MEDIUM RANGE MODELS DISAGREE ON HOW MUCH OF THAT WILL
GET CAUGHT UP IN SOUTHWEST FLOW ALOFT. FOR NOW WILL FOLLOW A MIDDLE
ROAD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 81 61 77 67 70 / 0 0 20 40 50
VICTORIA 78 52 74 60 65 / 0 0 10 40 50
LAREDO 83 62 78 65 66 / 0 10 10 20 50
ALICE 82 58 78 65 68 / 0 0 20 30 50
ROCKPORT 80 62 76 66 70 / 0 0 20 40 50
COTULLA 81 56 76 62 64 / 0 0 10 20 50
KINGSVILLE 82 61 78 66 70 / 0 0 20 30 50
NAVY CORPUS 79 64 76 68 71 / 0 0 20 40 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TE/81...AVIATION
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
856 AM CST THU NOV 19 2015
.DISCUSSION...QUIET WEATHER CONDITIONS WILL PERSIST TODAY AS WINDS
GRADUALLY VEER TO THE E AND SLOWLY ADVECT LOW LEVEL MOISTURE BACK
INTO S TX. HIGHS ARE EXPECTED TO BE A TAD WARMER THAN YESTERDAY`S
VALUES. OVERALL FCST LOOKS ON TRACK WITH NO MAJOR CHANGES AT THIS
TIME. WILL UPDATE ZONES TO REMOVE MENTION OF MORNING FOG.
&&
.PREV DISCUSSION... /ISSUED 538 AM CST THU NOV 19 2015/
DISCUSSION...SEE AVIATION SECTION FOR 12Z TAFS.
AVIATION...ALTHOUGH THE TEMP/DEWPOINT SPREADS ARE NEAR ZERO FOR
THE COASTAL PLAINS...FOG HAS BEEN SLOW TO FORM WITH ONLY SPOTTY
OCCURRENCES OVER THE PAST COUPLE OF HOURS. WINDS ARE 5-7 KNOTS
FROM THE NORTH WHICH MAY KEEP FOG FROM FORMING. WILL KEEP A
TEMPO GROUP FROM 12-14Z FOR VCT FOR FOG/MVFR VSBYS. THEN CLEAR
SKIES AND VFR CONDITIONS FOR MOST OF THE DAY TODAY. CLOUDS
AROUND 6 KFT OVER THE GULF WATERS EAST OF THE LOWER TEXAS COAST
SHOULD MOVE NORTHWARD LATE THIS AFTERNOON AND REACH THE SOUTHERN
PARTS OF THE COASTAL BEND/BRUSH COUNTRY. MOISTURE ADVECTION IN
THIS LAYER WILL INCREASE TONIGHT WITH BROKEN CLOUD DECK NEAR
5 KFT REACHING LRD AT 04Z AND AT CRP BY 08Z.
PREV DISCUSSION... /ISSUED 339 AM CST THU NOV 19 2015/
SHORT TERM (TODAY THROUGH FRIDAY)...LIGHT NORTHEAST WINDS AND
NEAR ZERO TEMP/DEWPOINT SPREAD WILL LEAD TO A BRIEF POTENTIAL FOR
FOG OVER THE COASTAL PLAINS EARLY THIS MORNING. FOG HAS BEEN
REPORTED AT PORT LAVACA IN THE PAST HOUR. ONLY MODEL INDICATING
A STRONG INDICATOR FOR FOG IS THE LATEST RAP MODEL. WILL HAVE TO
WATCH TRENDS TO SEE IF FOG BECOMES DENSE OVER THE NEXT COUPLE OF
HOURS.
OTHERWISE...ANOTHER BENIGN WEATHER DAY IS EXPECTED. SURFACE HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL BUILD EASTWARD INTO THE
MID MISSISSIPPI RIVER VALLEY TODAY. WINDS WILL INCREASE FROM THE
EAST-NORTHEAST LATER TODAY. HIGH TEMPERATURES WILL BE NEAR OR
SLIGHTLY WARMER THAN YESTERDAY.
LOW LEVEL FLOW WILL VEER TO EAST-SOUTHEAST LATER TONIGHT AS LOW
PRESSURE DEEPENS LEE OF THE CENTRAL ROCKIES. LOW CLOUDS ARE
EXPECTED TO RETURN ALONG THE RIO GRANDE INTO THE BRUSH COUNTRY
LATE TONIGHT. LOW LEVEL FLOW WILL BECOME SOUTHERLY FRIDAY WITH
MOISTURE STEADILY INCREASING WITH MOSTLY CLOUDY SKIES EXPECTED.
WEAK ISENTROPIC LIFT WILL LEAD TO A SLIGHT CHANCE OF LIGHT RAIN
OVER THE COASTAL WATERS INTO THE COASTAL BEND BY THE AFTERNOON.
WENT NEAR OR SLIGHTLY BELOW COOLER NAM GUIDANCE FOR HIGHS.
MARINE...EAST-NORTHEAST FLOW IS EXPECTED TO INCREASE BY THIS
AFTERNOON OVER THE OFFSHORE WATERS TO SCEC LEVELS AND REMAIN
AT THIS STRENGTH THROUGH THE NIGHT. SWELLS OF 4 TO 5 FEET WITH
PERIOD OF 8 SECONDS ALONG WITH EAST-NORTHEAST WINDS WILL KEEP
A MODERATE RISK OF RIP CURRENTS ALONG THE COAST.
LONG TERM (FRIDAY NIGHT THROUGH THANKSGIVING DAY)...CHANCES FOR
RAIN INCREASE OUT AHEAD OF A SIGNIFICANT COLD FRONT DUE TO MOVE
THROUGH SOUTH TEXAS SATURDAY MORNING. EXPECT SCATTERED
SHOWERS...WITH BETTER CHANCES OVER THE MIDDLE TEXAS COAST WHERE LOW
LEVEL MOISTURE WILL HAVE A BETTER CHANCE AT POOLING BEFORE FROPA.
HIGHS ON SATURDAY WILL OCCUR IMMEDIATELY BEFORE THE FRONT
PASSES...WITH TEMPERATURES FALLING QUICKLY BEHIND THE FRONT. WINDS
WILL ALSO PICK UP SUBSTANTIALLY BEHIND THE FRONT...WITH SMALL CRAFT
ADVISORY CONDITIONS EASILY MET FROM FROPA ALL THE WAY THROUGH EARLY
SUNDAY. CAA WILL KEEP TEMPERATURES IN THE 50S ON SUNDAY...AND
READINGS WILL DIP INTO THE 40S AWAY FROM THE COAST MONDAY MORNING AS
HIGH PRESSURE BUILDS INTO THE REGION.
HIGH PRESSURE WILL BEGIN TO SLIDE OFF TO THE EAST LATE
MONDAY...INITIATING RETURN FLOW ALONG THE COASTAL BEND. A FEATURE OF
INTEREST WILL BE MOISTURE FROM AN EASTERN PACIFIC TROPICAL
SYSTEM...AND MEDIUM RANGE MODELS DISAGREE ON HOW MUCH OF THAT WILL
GET CAUGHT UP IN SOUTHWEST FLOW ALOFT. FOR NOW WILL FOLLOW A MIDDLE
ROAD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 81 61 77 67 70 / 0 0 20 40 50
VICTORIA 78 52 74 60 65 / 0 0 10 40 50
LAREDO 83 62 78 65 66 / 0 10 10 20 50
ALICE 82 58 78 65 68 / 0 0 20 30 50
ROCKPORT 80 62 76 66 70 / 0 0 20 40 50
COTULLA 81 56 76 62 64 / 0 0 10 20 50
KINGSVILLE 82 61 78 66 70 / 0 0 20 30 50
NAVY CORPUS 79 64 76 68 71 / 0 0 20 40 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TE/81...SHORT TERM
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
538 AM CST THU NOV 19 2015
.DISCUSSION...SEE AVIATION SECTION FOR 12Z TAFS.
&&
.AVIATION...ALTHOUGH THE TEMP/DEWPOINT SPREADS ARE NEAR ZERO FOR
THE COASTAL PLAINS...FOG HAS BEEN SLOW TO FORM WITH ONLY SPOTTY
OCCURRENCES OVER THE PAST COUPLE OF HOURS. WINDS ARE 5-7 KNOTS
FROM THE NORTH WHICH MAY KEEP FOG FROM FORMING. WILL KEEP A
TEMPO GROUP FROM 12-14Z FOR VCT FOR FOG/MVFR VSBYS. THEN CLEAR
SKIES AND VFR CONDITIONS FOR MOST OF THE DAY TODAY. CLOUDS
AROUND 6 KFT OVER THE GULF WATERS EAST OF THE LOWER TEXAS COAST
SHOULD MOVE NORTHWARD LATE THIS AFTERNOON AND REACH THE SOUTHERN
PARTS OF THE COASTAL BEND/BRUSH COUNTRY. MOISTURE ADVECTION IN
THIS LAYER WILL INCREASE TONIGHT WITH BROKEN CLOUD DECK NEAR
5 KFT REACHING LRD AT 04Z AND AT CRP BY 08Z.
&&
.PREV DISCUSSION... /ISSUED 339 AM CST THU NOV 19 2015/
SHORT TERM (TODAY THROUGH FRIDAY)...LIGHT NORTHEAST WINDS AND
NEAR ZERO TEMP/DEWPOINT SPREAD WILL LEAD TO A BRIEF POTENTIAL FOR
FOG OVER THE COASTAL PLAINS EARLY THIS MORNING. FOG HAS BEEN
REPORTED AT PORT LAVACA IN THE PAST HOUR. ONLY MODEL INDICATING
A STRONG INDICATOR FOR FOG IS THE LATEST RAP MODEL. WILL HAVE TO
WATCH TRENDS TO SEE IF FOG BECOMES DENSE OVER THE NEXT COUPLE OF
HOURS.
OTHERWISE...ANOTHER BENIGN WEATHER DAY IS EXPECTED. SURFACE HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL BUILD EASTWARD INTO THE
MID MISSISSIPPI RIVER VALLEY TODAY. WINDS WILL INCREASE FROM THE
EAST-NORTHEAST LATER TODAY. HIGH TEMPERATURES WILL BE NEAR OR
SLIGHTLY WARMER THAN YESTERDAY.
LOW LEVEL FLOW WILL VEER TO EAST-SOUTHEAST LATER TONIGHT AS LOW
PRESSURE DEEPENS LEE OF THE CENTRAL ROCKIES. LOW CLOUDS ARE
EXPECTED TO RETURN ALONG THE RIO GRANDE INTO THE BRUSH COUNTRY
LATE TONIGHT. LOW LEVEL FLOW WILL BECOME SOUTHERLY FRIDAY WITH
MOISTURE STEADILY INCREASING WITH MOSTLY CLOUDY SKIES EXPECTED.
WEAK ISENTROPIC LIFT WILL LEAD TO A SLIGHT CHANCE OF LIGHT RAIN
OVER THE COASTAL WATERS INTO THE COASTAL BEND BY THE AFTERNOON.
WENT NEAR OR SLIGHTLY BELOW COOLER NAM GUIDANCE FOR HIGHS.
MARINE...EAST-NORTHEAST FLOW IS EXPECTED TO INCREASE BY THIS
AFTERNOON OVER THE OFFSHORE WATERS TO SCEC LEVELS AND REMAIN
AT THIS STRENGTH THROUGH THE NIGHT. SWELLS OF 4 TO 5 FEET WITH
PERIOD OF 8 SECONDS ALONG WITH EAST-NORTHEAST WINDS WILL KEEP
A MODERATE RISK OF RIP CURRENTS ALONG THE COAST.
LONG TERM (FRIDAY NIGHT THROUGH THANKSGIVING DAY)...CHANCES FOR
RAIN INCREASE OUT AHEAD OF A SIGNIFICANT COLD FRONT DUE TO MOVE
THROUGH SOUTH TEXAS SATURDAY MORNING. EXPECT SCATTERED
SHOWERS...WITH BETTER CHANCES OVER THE MIDDLE TEXAS COAST WHERE LOW
LEVEL MOISTURE WILL HAVE A BETTER CHANCE AT POOLING BEFORE FROPA.
HIGHS ON SATURDAY WILL OCCUR IMMEDIATELY BEFORE THE FRONT
PASSES...WITH TEMPERATURES FALLING QUICKLY BEHIND THE FRONT. WINDS
WILL ALSO PICK UP SUBSTANTIALLY BEHIND THE FRONT...WITH SMALL CRAFT
ADVISORY CONDITIONS EASILY MET FROM FROPA ALL THE WAY THROUGH EARLY
SUNDAY. CAA WILL KEEP TEMPERATURES IN THE 50S ON SUNDAY...AND
READINGS WILL DIP INTO THE 40S AWAY FROM THE COAST MONDAY MORNING AS
HIGH PRESSURE BUILDS INTO THE REGION.
HIGH PRESSURE WILL BEGIN TO SLIDE OFF TO THE EAST LATE
MONDAY...INITIATING RETURN FLOW ALONG THE COASTAL BEND. A FEATURE OF
INTEREST WILL BE MOISTURE FROM AN EASTERN PACIFIC TROPICAL
SYSTEM...AND MEDIUM RANGE MODELS DISAGREE ON HOW MUCH OF THAT WILL
GET CAUGHT UP IN SOUTHWEST FLOW ALOFT. FOR NOW WILL FOLLOW A MIDDLE
ROAD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 81 61 77 67 70 / 0 0 20 40 50
VICTORIA 78 52 74 60 65 / 0 0 10 40 50
LAREDO 83 62 78 65 66 / 0 10 10 20 50
ALICE 82 58 78 65 68 / 0 0 20 30 50
ROCKPORT 80 62 76 66 70 / 0 0 20 40 50
COTULLA 81 56 76 62 64 / 0 0 10 20 50
KINGSVILLE 82 61 78 66 70 / 0 0 20 30 50
NAVY CORPUS 79 64 76 68 71 / 0 0 20 40 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TMT/89...AVIATION
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
339 AM CST THU NOV 19 2015
.SHORT TERM (TODAY THROUGH FRIDAY)...LIGHT NORTHEAST WINDS AND
NEAR ZERO TEMP/DEWPOINT SPREAD WILL LEAD TO A BRIEF POTENTIAL FOR
FOG OVER THE COASTAL PLAINS EARLY THIS MORNING. FOG HAS BEEN
REPORTED AT PORT LAVACA IN THE PAST HOUR. ONLY MODEL INDICATING
A STRONG INDICATOR FOR FOG IS THE LATEST RAP MODEL. WILL HAVE TO
WATCH TRENDS TO SEE IF FOG BECOMES DENSE OVER THE NEXT COUPLE OF
HOURS.
OTHERWISE...ANOTHER BENIGN WEATHER DAY IS EXPECTED. SURFACE HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL BUILD EASTWARD INTO THE
MID MISSISSIPPI RIVER VALLEY TODAY. WINDS WILL INCREASE FROM THE
EAST-NORTHEAST LATER TODAY. HIGH TEMPERATURES WILL BE NEAR OR
SLIGHTLY WARMER THAN YESTERDAY.
LOW LEVEL FLOW WILL VEER TO EAST-SOUTHEAST LATER TONIGHT AS LOW
PRESSURE DEEPENS LEE OF THE CENTRAL ROCKIES. LOW CLOUDS ARE
EXPECTED TO RETURN ALONG THE RIO GRANDE INTO THE BRUSH COUNTRY
LATE TONIGHT. LOW LEVEL FLOW WILL BECOME SOUTHERLY FRIDAY WITH
MOISTURE STEADILY INCREASING WITH MOSTLY CLOUDY SKIES EXPECTED.
WEAK ISENTROPIC LIFT WILL LEAD TO A SLIGHT CHANCE OF LIGHT RAIN
OVER THE COASTAL WATERS INTO THE COASTAL BEND BY THE AFTERNOON.
WENT NEAR OR SLIGHTLY BELOW COOLER NAM GUIDANCE FOR HIGHS.
&&
.MARINE...EAST-NORTHEAST FLOW IS EXPECTED TO INCREASE BY THIS
AFTERNOON OVER THE OFFSHORE WATERS TO SCEC LEVELS AND REMAIN
AT THIS STRENGTH THROUGH THE NIGHT. SWELLS OF 4 TO 5 FEET WITH
PERIOD OF 8 SECONDS ALONG WITH EAST-NORTHEAST WINDS WILL KEEP
A MODERATE RISK OF RIP CURRENTS ALONG THE COAST.
&&
.LONG TERM (FRIDAY NIGHT THROUGH THANKSGIVING DAY)...CHANCES FOR
RAIN INCREASE OUT AHEAD OF A SIGNIFICANT COLD FRONT DUE TO MOVE
THROUGH SOUTH TEXAS SATURDAY MORNING. EXPECT SCATTERED
SHOWERS...WITH BETTER CHANCES OVER THE MIDDLE TEXAS COAST WHERE LOW
LEVEL MOISTURE WILL HAVE A BETTER CHANCE AT POOLING BEFORE FROPA.
HIGHS ON SATURDAY WILL OCCUR IMMEDIATELY BEFORE THE FRONT
PASSES...WITH TEMPERATURES FALLING QUICKLY BEHIND THE FRONT. WINDS
WILL ALSO PICK UP SUBSTANTIALLY BEHIND THE FRONT...WITH SMALL CRAFT
ADVISORY CONDITIONS EASILY MET FROM FROPA ALL THE WAY THROUGH EARLY
SUNDAY. CAA WILL KEEP TEMPERATURES IN THE 50S ON SUNDAY...AND
READINGS WILL DIP INTO THE 40S AWAY FROM THE COAST MONDAY MORNING AS
HIGH PRESSURE BUILDS INTO THE REGION.
HIGH PRESSURE WILL BEGIN TO SLIDE OFF TO THE EAST LATE
MONDAY...INITIATING RETURN FLOW ALONG THE COASTAL BEND. A FEATURE OF
INTEREST WILL BE MOISTURE FROM AN EASTERN PACIFIC TROPICAL
SYSTEM...AND MEDIUM RANGE MODELS DISAGREE ON HOW MUCH OF THAT WILL
GET CAUGHT UP IN SOUTHWEST FLOW ALOFT. FOR NOW WILL FOLLOW A MIDDLE
ROAD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 81 61 77 67 70 / 0 0 20 40 50
VICTORIA 78 52 74 60 65 / 0 0 10 40 50
LAREDO 83 62 78 65 66 / 0 10 10 20 50
ALICE 82 58 78 65 68 / 0 0 20 30 50
ROCKPORT 80 62 76 66 70 / 0 0 20 40 50
COTULLA 81 56 76 62 64 / 0 0 10 20 50
KINGSVILLE 82 61 78 66 70 / 0 0 20 30 50
NAVY CORPUS 79 64 76 68 71 / 0 0 20 40 50
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TMT/89...SHORT TERM
JV/71...LONG TERM
AREA FORECAST DISCUSSION
NWS SEATTLE WA
902 AM PST THU NOV 19 2015
.SYNOPSIS...DRY NORTHWEST FLOW ALOFT WILL ALLOW SKIES TO CLEAR OVER
WESTERN WASHINGTON TODAY. AN UPPER LEVEL RIDGE AND LOW LEVEL
OFFSHORE FLOW WILL BRING MOSTLY CLEAR COOL WEATHER TONIGHT THROUGH
THE WEEKEND. A LARGE COLD UPPER LEVEL TROUGH WILL MOVE OVER THE
REGION EARLY NEXT WEEK WITH A POSSIBILITY OF SOME SNOW AT LOWER
ELEVATIONS.
&&
.SHORT TERM...LAST NIGHTS FRONTAL SYSTEM IS JUST ABOUT OUT OF W WA
AT 8 AM THIS MORNING WITH SOME LAST AREAS OF RAIN DEPARTING FROM THE
CASCADES IN EASTERN LEWIS COUNTY. CLEARING IS UNDERWAY ON THE COAST
AND OVER MUCH OF THE NORTHERN HALF OF THE W WA INTERIOR. ONE NOTABLE
EXCEPTION IS THE EASTERN STRAIT OF JUAN DE FUCA AREA FROM SEQUIM TO
PORT ANGELES...WHERE N WINDS FLOWING ACROSS THE STRAIT HAVE BEEN
BRINGING UPSLOPE SHOWERS AND CLOUDS TO THE AREA. PER THE HRRR MODEL
THE SHOWERS WILL PROBABLY CONTINUE OFF AND ON UNTIL ABOUT NOON.
MOSTLY CLEAR SKIES TONIGHT WILL ALLOW LOW TEMPERATURES TO DROP INTO
THE UPPER 20S AND 30S FRIDAY MORNING.
AN UPPER LEVEL RIDGE WILL BUILD OVER THE REGION FRIDAY AND
SATURDAY...THEN WEAKEN ON SUNDAY. AT THE SAME TIME...A SURFACE RIDGE
OVER SOUTHERN B.C. WILL MAINTAIN DRY E-NE OFFSHORE FLOW. THIS WILL
KEEP SKIES MOSTLY CLEAR OVER W WA WITH ONLY PATCHY MORNING FOG. LOW
TEMPERATURES WILL DROP INTO THE MID 20S TO MID 30S SATURDAY MORNING
AND MAINLY THE 30S ON SUNDAY MORNING. THE FREEZING TEMPERATURES AND
PATCHY FOG COULD COMBINE TO PRODUCE ISOLATED FREEZING FOG...POSSIBLY
LAYING ISOLATED ICE PATCHES ON ROAD WAYS. KAM
.LONG TERM...PREVIOUS DISCUSSION FROM THE 328 AM AFD...THE UPPER
RIDGE WILL BEGIN WEAKENING AND MOVING EAST OF THE REGION ON
SUNDAY...BUT IT SHOULD BE ANOTHER DRY DAY. A WEAK SYSTEM WILL
PROBABLY MOVE INTO THE PACIFIC NORTHWEST ON MONDAY FOR A CHANCE OF
SHOWERS. MODELS HAVE BEEN FAIRLY CONSISTENT WITH THE IDEA THAT A
DEEP UPPER LOW WILL DIG SOUTHWARD ACROSS THE REGION FROM AROUND
MONDAY NIGHT THROUGH WEDNESDAY...AS AN UPPER RIDGE AMPLIFIES
UPSTREAM ALONG 140W. THE UPPER LOW WILL LIKELY MOVE FROM VANCOUVER
ISLAND ACROSS WESTERN WASHINGTON AND THEN INTO SOUTHEAST OREGON OR
NORTHERN NEVADA...WITH A COLD SURFACE HIGH MIGRATING SOUTH THROUGH
BRITISH COLUMBIA. THE RESULT WILL BE A COLD AIR MASS PUSHING INTO
THE FORECAST AREA WITH THE POSSIBILITY OF LOW ELEVATION SNOWFALL.
MCDONNAL
&&
.AVIATION...A WEAK SYSTEM IS PASSING THROUGH NORTHERN OREGON THIS
MORNING WITH LIGHT SHOWERS CLIPPING THE SOUTHERN TIER OF THE
CWA...MAINLY LEWIS COUNTY. THESE SHOWERS WILL DIMINISH THIS
AFTERNOON AS THIS SYSTEM EXITS. THERE ARE ALSO SHOWERS AND MVFR CIGS
IN THE EASTERN STRAIT OF JUAN DE FUCA FROM NE UPSLOPE WINDS.
OTHERWISE EXPECT VFR CONDITIONS TODAY WITH NORTHERLY WINDS AT THE
SURFACE...AND W/NW FLOW ALOFT.
AN UPPER LEVEL RIDGE WILL MAINTAIN DRY AND STABLE CONDITIONS
TONIGHT. EXPECT CLEAR SKIES WITH OFFSHORE FLOW...HOWEVER MAY SEE
SHALLOW PATCHY FOG IN THE SOUTH SOUND. 33
KSEA...CLOUDS WILL SCATTER OUT TODAY WITH VFR CONDITIONS EXPECTED.
NORTH WINDS AT THE SURFACE TO 12 KT. 33
&&
.MARINE...NORTHERLY FLOW WILL PREVAIL TODAY AS A SURFACE LOW MOVES
EAST THROUGH NORTHERN OREGON. BORDERLINE SMALL CRAFT ADVISORY WINDS
ARE FORECAST OVER THE WATERS. THE FLOW WILL TURN OFFSHORE ON FRIDAY
AS HIGH PRESSURE BUILDS OVER INTERIOR BRITISH COLUMBIA AND EASTERN
WA. OFFSHORE FLOW WILL CONTINUE THROUGH EARLY NEXT WEEK. 33
&&
.HYDROLOGY...LIGHT PRECIPITATION WILL COME TO AN END OVER THE
AREA THIS MORNING. TOTAL PRECIPITATION AMOUNTS FROM THIS
SYSTEM WILL NOT BE HYDROLOGICALLY SIGNIFICANT. LITTLE IN THE WAY OF
PRECIPITATION IS FORECAST FOR THE NEXT 7 DAYS.
RIVERS ARE RECEDING EARLY THIS MORNING WITH THE EXCEPTION OF THE SLOW
MOVING CHEHALIS. THE CHEHALIS CRESTED AT CENTRALIA OVERNIGHT.
THE CREST WILL MOVE DOWNSTREAM REACHING GRAYS HARBOR EARLY
SATURDAY MORNING. FLOOD WARNINGS ON THE GREEN AND COWLITZ WILL
BE CANCELLED THIS MORNING WITH BOTH RIVERS NOW BELOW FLOOD
STAGE. FLOOD WARNINGS REMAIN ON ALL OR PART OF THE SNOHOMISH
...SNOQUALMIE...CHEHALIS...SKAGIT AND SKOKOMISH RIVERS. THE FLOOD
WARNINGS FOR THE LOWER PORTIONS OF THE SKAGIT AND SNOQUALMIE AS
WELL AS THE UPPER PORTION OF THE SNOHOMISH WILL COME TO AN END LATER
THIS MORNING. BY TONIGHT FLOOD WARNINGS WILL ONLY REMAIN ON THE
CHEHALIS AND POSSIBLY THE LOWER REACHES OF THE SNOHOMISH. FELTON
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...A FEW FLOOD WARNINGS REMAIN IN EFFECT FOR VARIOUS RIVER
FORECAST POINTS.
PZ...SMALL CRAFT ADVISORIES FOR ALL WATERS EXCEPT GRAYS HARBOR BAR.
&&
$$
WWW.WEATHER.GOV/SEATTLE
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
740 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 740 PM CST FRI NOV 20 2015
LOOKING A LOT MORE LIKE LATE NOVEMBER OUT THERE...AT LEAST FOR
PARTS OF THE AREA. NICE TO SEE THAT THIS STORM SYSTEM OVERALL IS
UNFOLDING AS EXPECTED THE PAST 24-36 HOURS...WITH INCOMING AMOUNTS
ACROSS MUCH OF THE CURRENT WARNING AREA MAINLY IN THE 4-7 INCH
RANGE SO FAR...HEAVIEST OF COURSE WHERE INDIVIDUAL STRONGER FGEN
BANDED ELEMENTS HAVE LAID OUT THE LONGEST...PRIMARILY SOUTH OF
HIGHWAY 18. FARTHER NORTH...AMOUNTS HAVE TAPERED CONSIDERABLY...
GENERALLY ONLY PUSHING AN INCH OR TWO ALONG THE IA/MN BORDER PER
REPORTS...AND ONLY A DUSTING TO PERHAPS A HALF INCH JUST SOUTH OF
THE I-90 CORRIDOR. THESE AMOUNTS ARE PRETTY MUCH IN LINE WITH
EARLIER THINKING..
DON`T PLAN ANY BIG CHANGES TO GOING HEADLINES...THOUGH MAY
ULTIMATELY HAVE TO DITCH THE WARNING FOR RICHLAND COUNTY PER RADAR
TRENDS...AS THE STRONGER FGEN BAND HAS REALLY WEAKENED OVER THAT
AREA THE PAST HOUR OR TWO. ALSO...WILL LIKELY NEED TO SPEED UP THE
EXIT TIME OF WIDESPREAD PRECIP PER RADAR TRENDS...THOUGH WITH THE
ARRIVAL OF THE ACTUAL UPPER WAVE...WE MAY TEND TO SEE SOME
REDEVELOPMENT WITHIN AN ELONGATING MID LEVEL DEFORMATION AXIS INTO
FAR SOUTHWEST WISCONSIN AND NORTHEAST IOWA. REGARDLESS OF THE
ACTUAL TIME...CURRENT HEADLINES DO COVER THE BIGGER ISSUE...WHICH
HAS BEEN IMPACT WITH QUITE A FEW REPORTS OF ACCIDENTS...CERTAINLY
NOT HELPED BY THE FACT THAT THIS IS THE FIRST EVENT OF THE SEASON.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
HAVE BEEN TRYING TO INTEGRATE CURRENT RADAR AND SURFACE
OBSERVATIONS INTO THE FORECAST TO FINE TUNE STORM. BOTTOM LINE IS
THE ADVISORIES AND WARNINGS LOOK ON TRACK FOR LOCATION. WE DID
UPDATE THE START TIME. HAVE LEFT THE END TIME ON SATURDAY AS THE
NORTHWEST WINDS OF 15 TO 25 MPH WILL CAUSE SOME DRIFTING...
ESPECIALLY ON THE HIGHER TERRAIN OF SWRN WI AND NERN IA.
CURRENT SNOW BAND IS IMPRESSIVE WITH AMOUNTS NEAR 15 INCHES NEAR
SIOUX FALLS SD TODAY AND MESSY ROADS EXTENDING NOW INTO PARTS OF
NERN IA UNDER THE SNOW BAND. GIVEN A MODERATE SNOW
RATE IN THE CENTRAL-EASTERN IA SNOW BAND...ACCUMULATING SNOW AND
SLICK ROADS HAPPEN FAIRLY QUICK AFTER ONSET. THIS BAND IS WELL
REPRESENTED BY 600-700 MB FRONTOGENESIS FORCING PER RAP ANALYSIS.
THE BAND SHOULD CONTINUE TO SHIFT NORTHEAST THROUGH EARLY EVENING. PER
VIGOROUS SHORTWAVE TROUGH IN KS/NEB MOVING AT US...THE
FRONTOGENESIS THEN REINVIGORATES A BIT LATER EVENING ON A NE-SW
ARC OVER THE SOUTHERN FORECAST AREA...WITH THE MAIN HEAVY SNOW
BAND NEAR HIGHWAY 20 TO I-80 WITH STRONGER FRONTOGENESIS INDICATED
IN THE SHORT TERM MODELS.
BIG PICTURE REMAINS THE SAME FOR THIS STORM. WE HAVEN`T CHANGED
THE TOTAL LIQUID FROM THIS STORM MUCH...BUT DO HAVE SOME CONCERNS
WITH SNOW RATIOS IN THE WARNING...ESPECIALLY CLOSER TO DUBUQUE AND
THE SOUTHERN HALF OF THE FAYETTE-CLAYTON-GRANT COUNTIES. THE
LATEST RAP AND 20.12Z NAM/GFS OUTPUT RUN THROUGH THE DENDRITIC
GROWTH ZONE COBB TECHNIQUE SUGGEST RATIOS COULD BE IN THE 20-24 TO
1 RANGE. WE HAVE INCREASED THOSE RATIOS TO 17 TO 1 ACROSS THE
WARNING WITH A 150-200 MB DENDRITE GROWTH ZONE SUGGESTED. THIS
RAISES TOTALS TOWARD A FOOT. WINDS WILL INCREASE ACROSS THE SOUTH
INTO THE 15 TO 25 MPH RANGE SATURDAY FOR A BIT OF DRIFTING SNOW.
MAIN MESSAGE IS THE SAME...WITH POSSIBLY A BIT MORE IMPACT ACROSS
THE FAR SOUTH /IA HIGHWAY 3/ WITH 10-12 INCHES AND SOME DRIFTING
SNOW. BELIEVE ACCUMULATING SNOW WILL REALLY BE SOUTH OF I-90...AND
THE HAZARDS LOOK LIKE THEY ARE PLACED WELL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
NORTHWEST FLOW CONTINUES WITH A COLD WEEKEND. CONSENSUS
DETERMINISTIC MODEL RUNS FROM 20.12Z AGREED WELL ON A DYNAMIC
SYSTEM SHIFTING THROUGH NERN WI RAPIDLY SUNDAY NIGHT. THIS LOOKS
LIKE IT COULD SPREAD SOME SNOW ACROSS NORTHCENTRAL WI...LEAVING BY
MONDAY.
THE WEEK THEN BEGINS TO WARM AS ANOTHER LONGWAVE TROUGH DIGS IN
THE WEST. BY MID-WEEK PRECIPITATION WORKS INTO THE AREA ON A
MOIST FLOW. A CLOUDY PERIOD WITH POSSIBLY PRECIPITATION TYPE
ISSUES. AT THIS TIME IT APPEARS MAINLY LIKE A RAIN/SNOW SCENARIO
BUT DEPENDING ON HOW MOISTURE ARRIVES...SOME FREEZING DRIZZLE
COULD BE AROUND. THE MAIN IDEA NOW IS WARMING AND PRECIPITATION BY
MID-WEEK INTO THANKSGIVING. CONFIDENCE MODERATE WITH GOOD
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 525 PM CST FRI NOV 20 2015
SNOW IS OVERSPREADING BOTH KLSE AND KRST CURRENTLY...WITH A PERIOD
OF IFR CONDITIONS EXPECTED FOR BOTH SITES THROUGH ABOUT 04-05Z
BEFORE SNOW QUICKLY ENDS AND CEILINGS RISE BACK TO THE 8-10KFT
RANGE. ANY SNOW ACCUMULATION AT BOTH AIRPORTS LOOKS FAIRLY
LIGHT...BUT UP TO AN INCH IS POSSIBLE. OTHERWISE...SKIES SHOULD
MAKE A STRONG ATTEMPT TO CLEAR VERY LATE TONIGHT...BUT WILL BE
WATCHING SOME LOWER CLOUDS UPSTREAM OVER NORTHERN MINNESOTA...WITH
SOME HINTS THAT THESE MAY TRY THEIR BEST TO WORK DOWN THIS WAY AS
OUR CURRENT STORM SYSTEM BEGINS TO DEPART. FOR NOW...CONFIDENCE
REMAINS LOW ENOUGH TO PRECLUDE ANY MENTION...BUT IF THEY DO
OCCUR...ANOTHER BOUT OF MVFR CEILINGS IS POSSIBLE. LIGHT AND
VARIABLE (OR CALM) WINDS THROUGH LATE EVENING WILL SLOWLY SHIFT
NORTHERLY AND STRENGTHEN TO THE 12-16 KNOT RANGE ON SATURDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR WIZ054-055-061.
WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR WIZ053.
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR MNZ096.
IA...WINTER STORM WARNING UNTIL 6 AM CST SATURDAY FOR IAZ008-009-018-
019.
WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR IAZ010-011-029-
030.
&&
$$
UPDATE...LAWRENCE
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...LAWRENCE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
525 PM CST FRI NOV 20 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
HAVE BEEN TRYING TO INTEGRATE CURRENT RADAR AND SURFACE
OBSERVATIONS INTO THE FORECAST TO FINE TUNE STORM. BOTTOM LINE IS
THE ADVISORIES AND WARNINGS LOOK ON TRACK FOR LOCATION. WE DID
UPDATE THE START TIME. HAVE LEFT THE END TIME ON SATURDAY AS THE
NORTHWEST WINDS OF 15 TO 25 MPH WILL CAUSE SOME DRIFTING...
ESPECIALLY ON THE HIGHER TERRAIN OF SWRN WI AND NERN IA.
CURRENT SNOW BAND IS IMPRESSIVE WITH AMOUNTS NEAR 15 INCHES NEAR
SIOUX FALLS SD TODAY AND MESSY ROADS EXTENDING NOW INTO PARTS OF
NERN IA UNDER THE SNOW BAND. GIVEN A MODERATE SNOW
RATE IN THE CENTRAL-EASTERN IA SNOW BAND...ACCUMULATING SNOW AND
SLICK ROADS HAPPEN FAIRLY QUICK AFTER ONSET. THIS BAND IS WELL
REPRESENTED BY 600-700 MB FRONTOGENESIS FORCING PER RAP ANALYSIS.
THE BAND SHOULD CONTINUE TO SHIFT NORTHEAST THROUGH EARLY EVENING. PER
VIGOROUS SHORTWAVE TROUGH IN KS/NEB MOVING AT US...THE
FRONTOGENESIS THEN REINVIGORATES A BIT LATER EVENING ON A NE-SW
ARC OVER THE SOUTHERN FORECAST AREA...WITH THE MAIN HEAVY SNOW
BAND NEAR HIGHWAY 20 TO I-80 WITH STRONGER FRONTOGENESIS INDICATED
IN THE SHORT TERM MODELS.
BIG PICTURE REMAINS THE SAME FOR THIS STORM. WE HAVEN`T CHANGED
THE TOTAL LIQUID FROM THIS STORM MUCH...BUT DO HAVE SOME CONCERNS
WITH SNOW RATIOS IN THE WARNING...ESPECIALLY CLOSER TO DUBUQUE AND
THE SOUTHERN HALF OF THE FAYETTE-CLAYTON-GRANT COUNTIES. THE
LATEST RAP AND 20.12Z NAM/GFS OUTPUT RUN THROUGH THE DENDRITIC
GROWTH ZONE COBB TECHNIQUE SUGGEST RATIOS COULD BE IN THE 20-24 TO
1 RANGE. WE HAVE INCREASED THOSE RATIOS TO 17 TO 1 ACROSS THE
WARNING WITH A 150-200 MB DENDRITE GROWTH ZONE SUGGESTED. THIS
RAISES TOTALS TOWARD A FOOT. WINDS WILL INCREASE ACROSS THE SOUTH
INTO THE 15 TO 25 MPH RANGE SATURDAY FOR A BIT OF DRIFTING SNOW.
MAIN MESSAGE IS THE SAME...WITH POSSIBLY A BIT MORE IMPACT ACROSS
THE FAR SOUTH /IA HIGHWAY 3/ WITH 10-12 INCHES AND SOME DRIFTING
SNOW. BELIEVE ACCUMULATING SNOW WILL REALLY BE SOUTH OF I-90...AND
THE HAZARDS LOOK LIKE THEY ARE PLACED WELL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
NORTHWEST FLOW CONTINUES WITH A COLD WEEKEND. CONSENSUS
DETERMINISTIC MODEL RUNS FROM 20.12Z AGREED WELL ON A DYNAMIC
SYSTEM SHIFTING THROUGH NERN WI RAPIDLY SUNDAY NIGHT. THIS LOOKS
LIKE IT COULD SPREAD SOME SNOW ACROSS NORTHCENTRAL WI...LEAVING BY
MONDAY.
THE WEEK THEN BEGINS TO WARM AS ANOTHER LONGWAVE TROUGH DIGS IN
THE WEST. BY MID-WEEK PRECIPITATION WORKS INTO THE AREA ON A
MOIST FLOW. A CLOUDY PERIOD WITH POSSIBLY PRECIPITATION TYPE
ISSUES. AT THIS TIME IT APPEARS MAINLY LIKE A RAIN/SNOW SCENARIO
BUT DEPENDING ON HOW MOISTURE ARRIVES...SOME FREEZING DRIZZLE
COULD BE AROUND. THE MAIN IDEA NOW IS WARMING AND PRECIPITATION BY
MID-WEEK INTO THANKSGIVING. CONFIDENCE MODERATE WITH GOOD
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 525 PM CST FRI NOV 20 2015
SNOW IS OVERSPREADING BOTH KLSE AND KRST CURRENTLY...WITH A PERIOD
OF IFR CONDITIONS EXPECTED FOR BOTH SITES THROUGH ABOUT 04-05Z
BEFORE SNOW QUICKLY ENDS AND CEILINGS RISE BACK TO THE 8-10KFT
RANGE. ANY SNOW ACCUMULATION AT BOTH AIRPORTS LOOKS FAIRLY
LIGHT...BUT UP TO AN INCH IS POSSIBLE. OTHERWISE...SKIES SHOULD
MAKE A STRONG ATTEMPT TO CLEAR VERY LATE TONIGHT...BUT WILL BE
WATCHING SOME LOWER CLOUDS UPSTREAM OVER NORTHERN MINNESOTA...WITH
SOME HINTS THAT THESE MAY TRY THEIR BEST TO WORK DOWN THIS WAY AS
OUR CURRENT STORM SYSTEM BEGINS TO DEPART. FOR NOW...CONFIDENCE
REMAINS LOW ENOUGH TO PRECLUDE ANY MENTION...BUT IF THEY DO
OCCUR...ANOTHER BOUT OF MVFR CEILINGS IS POSSIBLE. LIGHT AND
VARIABLE (OR CALM) WINDS THROUGH LATE EVENING WILL SLOWLY SHIFT
NORTHERLY AND STRENGTHEN TO THE 12-16 KNOT RANGE ON SATURDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR WIZ054-061.
WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR WIZ055.
WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR WIZ053.
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR MNZ096.
IA...WINTER STORM WARNING UNTIL 6 AM CST SATURDAY FOR IAZ008-009-018-
019.
WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR IAZ010-011-029-
030.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...LAWRENCE
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
348 AM EST SAT NOV 21 2015
.DISCUSSION...
...INCREASED RAIN CHANCES THIS WEEKEND...
...HAZARDOUS BOATING CONDITIONS DEVELOPING SUNDAY AND CONTINUING
MOST OF NEXT WEEK...
TODAY-TONIGHT...HIGH MOISTURE BAND VICINITY OF OLD FRONT WAS OVER
SOUTH FLORIDA AND INTO THE GULF OF MEXICO. SHORTWAVE TROUGH WILL
MOVE THROUGH THE MID PART OF THE COUNTRY AND INDUCE A WEAK WAVE OF
LOW PRESSURE ALONG THE BOUNDARY IN THE GULF. THIS WILL ALLOW THE
BOUNDARY AND ASSOCIATED HIGH MOISTURE TO LIFT A LITTLE NORTHWARD.
THOUGH WE WILL HAVE CONSIDERABLE HIGH LEVEL CLOUDINESS TO START
OFF THE DAY...EXPECT A LITTLE HEATING AND WITH 500 MB TEMPS AROUND
MINUS 9 CELSIUS...SUFFICIENT INSTABILITY WILL EXIST FOR ISOLATED
LIGHTNING STORMS.
THE HRRR MODEL HOURLY RUNS HAVE RANGED FROM EARLY CONVECTION
ALONG REMNANT OLD FRONTAL BOUNDARY IN THE SOUTH...TO MORE RECENTLY
HIGHLIGHTING NORTHERN AREAS WITH THE MOST CONVECTION AS EAST COAST
SEA BREEZE MOVES INLAND. EARLY MORNING RADAR HAS NOT BEEN SHOWING
MUCH SHOWER ACTIVITY OVER THE ATLANTIC AND WITH LIMITED DIRECT
SOLAR INSOLATION TODAY...PREFER NOT TO GO WITH LIKELY POPS.
INSTEAD WILL GO 50 PERCENT EVERYWHERE...WHICH IS WHAT THE 00Z MOS
VALUES WERE.
SOME OF THE DAYTIME CONVECTION MAY LINGER INTO EVENING...BUT THE
GREATEST LARGE SCALE ASCENT AHEAD OF THE SHORTWAVE WILL BE AFTER
MIDNIGHT. MOS POPS ARE VERY HIGH TONIGHT...75-90 PERCENT...WHICH
LOOKS REASONABLE GIVEN THE IMPRESSIVE DIVERGENCE ALOFT DEPICTED BY
THE GFS. HOWEVER THE BULK OF THIS PRECIP SHOULD BE QUITE LATE...
SO HAVE KEPT OUR PREVIOUS FORECAST FOR AREAWIDE 70 PERCENT
CHANCES. WILL ALSO KEEP MENTION OF SLIGHT CHANCE FOR STORMS
OVERNIGHT DUE TO LARGE SCALE ASCENT AND WEAK ELEVATED INSTABILITY.
SUN...AN AMORPHOUS AREA OF LOW PRESSURE WILL STRETCH FROM OFF THE
SOUTHWEST COAST OF FLORIDA TOWARD THE ATLANTIC WATERS OFFSHORE
GEORGIA/SOUTH CAROLINA. THE LOW WILL ORGANIZE NORTH OF THE BAHAMAS
BEFORE ADVANCING QUICKLY TO THE NORTH AND EAST. AS IT DOES SO...A
STRONG COLD FRONT WILL ADVANCE OVER THE AREA LATE SUNDAY INTO EARLY
MONDAY.
LARGE SCALE ASCENT ALOFT WILL BE ONGOING THROUGH THE MORNING AS LOW
LEVEL CONVERGENCE IN ASSOCIATION WITH THE WEAK LOW SHIFTS TOWARDS
THE CENTRAL/SOUTHERN PENINSULA. EXPECT SHOWER COVERAGE TO BE
WIDESPREAD THROUGH AT LEAST THE FIRST HALF OF THE DAY. AS THE SYSTEM
PULLS AWAY LATE SUNDAY...RAIN CHANCES WILL LOWER AND ABATE FROM
NORTH TO SOUTH. CLOUDS WILL HOLD MAXES DOWN ON SUNDAY WHILE COLD AIR
ADVECTION BEGINS IN EARNEST SUNDAY NIGHT. EXPECTING A LARGE SPREAD
IN MINS...UPPER 40S ACROSS THE FAR NORTH AND 60-65 ALONG THE
TREASURE COAST. CONSIDERING THE VERY WARM TEMPERATURES THUS FAR THIS
FALL...AND THE FACT THAT WINDS ARE EXPECTED TO REMAIN BREEZY THROUGH
THE OVERNIGHT AND INTO EARLY MONDAY MORNING...IT WILL FEEL QUITE
CHILLY AS YOU HEAD OUT THE DOOR.
MON-FRI...COLD FRONT WILL BE WELL SOUTH OF THE AREA BY SUNRISE
MONDAY AS NORTHWEST WINDS USHER IN THE COOLEST AIR OF THE SEASON.
MAX HIGHS WILL STRUGGLE TO ESCAPE THE 60S DURING THE DAY ON MONDAY.
AS HAS BEEN THE CASE WITH NEARLY EVERY FROPA THIS SEASON...POST-
FRONTAL WINDS WILL RAPIDLY VEER ONSHORE...MODIFYING THE AIR MASS FOR
THE COASTAL COUNTIES AS EARLY AS MONDAY NIGHT. THIS WILL BE MOST
PRONOUNCED ALONG THE TREASURE COAST GIVEN THE STILL-WARM SHELF WATER
TEMPS THERE.
AS FLOW VEERS ONSHORE LATE MONDAY INTO TUESDAY...WILL LIKELY SEE
SIGNIFICANT MARINE STRATOCU FORM OVER THE ATLANTIC AND SPREAD
INLAND. BRIEF LIGHT RAIN / SPRINKLES POSSIBLE TUESDAY (CONFINED TO
THE COASTAL WATERS IN THIS FORECAST PACKAGE) BEFORE ONSHORE MOVING
SHOWERS RE-ENTER THE PICTURE MID-WEEK AND BEYOND AS MOISTURE
INCREASES IN DEEPENING EAST FLOW. MEANWHILE...TEMPS CLIMB TO NEAR
CLIMO BY WEDNESDAY AND ABOVE THU-FRI.
&&
.AVIATION...
CONDITIONS SO FAR THIS MORNING HAVE MAINLY BEEN VFR EXCEPT FOR A
FEW BRIEF MVFR CEILINGS. EXPECT THIS TREND TO CONTINUE...THEN AS
DAYTIME HEATING CLOUDS FORM...MORE AREAS OF MVFR CEILINGS SHOULD
FORM. SCATTERED SHOWERS AND A FEW STORMS ARE FORECAST DURING THE
AFTERNOON AND EARLY EVENING. A HIGHER COVERAGE OF SHOWERS AND
ISOLATED STORMS SHOULD SPREAD INLAND FROM THE GULF IN THE PRE
DAWN HOURS OF SUNDAY.
&&
.MARINE...
TODAY-TONIGHT...EAST WINDS WILL GRADUALLY VEER TO SOUTHEAST AND
EVEN SOUTH LATE IN THE DAY AS OLD FRONTAL TROUGH LIFTS BACK INTO
THE WATERS. SPEEDS LOOK TO BE 10-15 KNOTS EARLY THIS MORNING AND
EASING TO 10 KNOTS OR LESS THIS AFTERNOON. HAVE CANCELLED THE
SMALL CRAFT ADVISORY AS TIGHTENED PRESSURE GRADIENT WAS BRIEF OVER
OUR NORTHERN WATERS. EXPECT SCATTERED MAINLY AFTERNOON SHOWERS
WITH A SLIGHT CHANCE OF STORMS THROUGH EARLY EVENING. A HIGHER
COVERAGE OF SHOWERS WILL OCCUR IN THE PRE DAWN HOURS OF SUNDAY.
SUN-WED...PRESSURE GRADIENT WILL START OFF RELAXED EARLY SUNDAY
BEFORE TIGHTENING AS LOW PRESSURE ORGANIZES NORTH OF THE BAHAMAS. AS
THE LOW PULLS AWAY TO THE NORTH AND EAST...A STRONG COLD FRONT WILL
MOVE ACROSS THE COASTAL WATERS LATE SUNDAY. STRONG SUSTAINED
NORTHERLY WINDS OF AROUND 25 KNOTS WILL BUILD SEAS BEHIND THE
FRONT...RESULTING IN A QUICK TRANSITION TO HAZARDOUS BOATING/SURF
CONDITIONS THAT WILL LINGER THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. EXPECT HIGH END SCA CONDITIONS WITH GUSTS NEAR GALE
FORCE...AND SEAS AS HIGH AS 12-13FT IN THE GULF STREAM...PERHAPS
BRIEFLY HIGHER. WE ALSO MAY BE LOOKING AS DANGEROUS BEACH CONDITIONS
EARLY NEXT WEEK WITH HIGH/CHOPPY SURF AND STRONG RIPS WITH POTENTIAL
FOR ADVISORY CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 81 67 69 50 / 50 70 70 30
MCO 84 68 72 52 / 50 70 70 40
MLB 83 69 73 61 / 50 70 70 40
VRB 84 69 75 64 / 50 70 70 40
LEE 82 67 69 47 / 50 70 70 30
SFB 82 67 72 51 / 50 70 70 40
ORL 83 68 71 51 / 50 70 70 40
FPR 84 69 76 64 / 50 70 70 50
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
LONG TERM....ULRICH
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
336 AM CST SAT NOV 21 2015
.SHORT TERM...(Today)
ISSUED AT 336 AM CST SAT NOV 21 2015
the 09z/3am surface analysis shows the center of the low pressure in
south-central Missouri, with a warm front extending across southern
IL, roughly along I-70. The rain-snow line has maintained farther
north...with snow remaining north of a line from Macomb to Peoria to
Pontiac. The Peoria airport just SW of Peoria has little to no snow,
while the north side of Peoria has what looks to be at least an inch
of snow, and possibly more, on grassy surfaces based on IDOT
cameras. Reports of 2.5" of snow have come in from Knox county
observers in Altona and Abingdon earlier tonight.
The RAP and HRRR take the surface low across southern IL, with
deformation band snows continuing in our NW counties. Cold air along
the northern edge of the system will gradually get pulled southward
into our counties, prompting the rain to change to snow
progressively farther south and east. Snowfall amounts look on track
for our NW counties to be in the 3 to 6 inch range, with a sharp
cutoff down to an inch or less. As the deformation band progresses
across central IL into the afternoon, our NE counties could see
snowfall amounts up to an inch or possibly a little more toward
Hoopeston. We did not expand the winter weather advisory eastward, as
snow amounts should remain enough below the 3" criteria for
Champaign and Vermilion counties. The southern row of counties of
our advisory (Fulton, Tazewell, McLean) will be borderline in terms
of snow amounts as well, but will continue with headlines unchanged
as there remains some uncertainty as to how soon the cold air will
surge southward to change rain to snow, and how efficient of
snowfall production will occur in our NW areas.
Temps will remain warm enough for rain south of I-72 for a majority
of the day, with any change to snow coming so late in the event
that little to no snow accumulation is expected south of there.
The center of the surface low is forecast to pull into Indiana by 11
am/17z, so cold air will invade on strong NW winds by early
afternoon. High temps will likely occur by Noon in most areas
because of that, with steady or falling temps this afternoon as
winds increase to 25-30 mph. The snow should generally be too wet to
blow around, but wind chills could drop into the teens in our W-NW
counties.
&&
.LONG TERM...(Tonight through Friday)
ISSUED AT 336 AM CST SAT NOV 21 2015
Strong short wave to lift ne of central IL early this evening with
Canadian high pressure over the central Rockies quickly ridging east
into the mid MS river valley by dawn Sunday. Clouds to decrease from
west to east later this afternoon and into the evening while nw
winds 15-25 mph at sunset today diminish to 5-10 mph overnight.
Diminshing clouds and winds to bring a very cold night to the area
especially over northern CWA where snow cover where lows will be 7-
13F with mid teens over central parts of CWA and upper teens to near
20F in southeast IL. Wind chills will lower to 5 above to 5 below
zero northern cwa and 10-15 southeast IL. This will be the coldest
night since March 6th over central IL. High pressure ridges into the
Ohio river valley by sunset Sunday while upper level trof axis
shifts east of IL. A mostly sunny but cold day with highs ranging
form lower 30s from i-74 ne, mid 30s central CWA and upper 30s sw
CWA. Winds to become ssw at 7-14 mph by Sunday afternoon.
After a taste of winter weather this weekend for IL, temperatures to
moderate back above normal during the upcoming work week with upper
level heights rising over the region and nearly zonal upper level
flow Monday becoming sw by mid week with strong upper level ridge in
the east and strong upper level low/trof digging in the western
states. Dry weather expected Monday through Wednesday with temps
warming back up. Lows Sunday night in the mid to upper 20s. Highs
Monday range from lower 40s from I-74 ne where remaining snow cover
likely to melt while upper 40s to near 50F sw CWA. Highs by Wed in
the low to mid 50s and mid to upper 50s on Thanksgiving day. 00Z
models have trended slower with qpf returning to IL Wed night and
Thu and looks like a wet period from Wed night into early Sat. GFS
is quicker than ECMWF model with cold front moving through later Thu
night and Friday with highest pops will likely be. Between 1 and 2
inches of rain appear possible during this time frame. Rain chances
diminish next weekend and colder air returns to central/se IL.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 1055 PM CST FRI NOV 20 2015
Conditions are expected to deteriorate to IFR at all sites after
09z as a storm system tracks across the region. Low pressure will
pass south of the area on Saturday insuring a changeover to snow
at the TAF sites with PIA first in the 06-08z time frame...and
then over to BMI by 09z with CMI the last to see the change to
snow. Initially, surface temps will be above freezing but should
edge close to or just below freezing for a few hours Saturday
morning when we should see the steadier snowfall that will
accumulate. IFR conditions should gradualliy improve to MVFR
during the afternoon and then to VFR by 00z. Southeast to east
winds of 10 to 15 kts will back into the northeast and then
north by morning with speeds increasing to 15 to 25 kts during
the morning, and then continue into the afternoon. Gusts around
30 kts will be possible at times as well before we see northwest
winds diminish to around 10 kts around 00z.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until noon CST today for ILZ027>031-
036>038.
&&
$$
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CARIBOU ME
458 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE REGION TODAY. LOW PRESSURE WILL
MOVE NORTHWEST OF THE AREA ON SUNDAY WITH SOME RAIN. A SECOND
AREA OF LOW PRESSURE WILL LIFT ACROSS THE GULF OF MAINE SUNDAY
NIGHT AND THEN INTO THE MARITIMES ON MONDAY WITH MUCH COLDER AIR.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE WILL BUILD IN FROM THE WEST THIS MORNING WITH
CLEARING EARLY TODAY. THE HIGH PRESSURE SYSTEM WILL CREST OVER THE
REGION TODAY THEN MOVE OFF TO THE EAST THIS EVENING. WEAK LOW
PRESSURE WILL DEVELOP OVER THE GULF OF MAINE BEHIND THE DEPARTING
LOW AND SPREAD RAIN AND SNOW INTO NEW BRUNSWICK TONIGHT. INTENSE
LOW PRESSURE WILL MOVE INTO THE GREAT LAKES TONIGHT THEN MOVE INTO
SOUTHEASTERN QUEBEC PROVINCE EARLY SUNDAY.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
AN INTERESTING SETUP FOR SUNDAY NIGHT INTO EARLY MONDAY.
A FRONTAL SYSTEM IS FORECAST TO SLIDE ACROSS THE AREA ON SUNDAY
W/SOME SHOWERS OR LIGHT RAIN PULLING OUT OF THE AREA IN THE
MORNING. THE 2ND BATCH OF PRECIP IN THE FORM OF RAIN IS EXPECTED
TO SET UP LATER IN DAY AS LOW PRES DEVELOPS OFF THE SOUTHERN NEW
ENGLAND COAST AND LIFTS NNE. THE AREAS THAT WILL SEE MEASURABLE
QPF WILL BE ACROSS THE EASTERN 1/2 OF THE CWA WHERE THE BEST
FORCING AND LLVL CONVERGENCE WILL BE LOCATED. AS THE LOW LIFTS TO
NNE AND THE UPPER TROF DIGS SOME AS IT SWINGS INTO THE NE, COLDER
AIR WILL START TO FILTER INTO THE REGION. THE ECMWF AND GFS ARE IN
AGREEMENT W/THE COLDER AIR COMING IN BY THE EVENING WHILE THE
CANADIAN GEM & NAM HOLD THE COLDER AIR BACK BY 3-6 HRS. DECIDED TO
GO W/A CONSENSUS BLEND OF THE GUIDANCE FOR THIS PACKAGE SHOWING
RAIN GOING OVER TO A PERIOD OF SNOW BY 11 PM OR SO. ALL THE
GUIDANCE IS IN AGREEMENT THAT THE BULK OF THE QPF WILL BE ACROSS
THE EASTERN 3RD OF THE CWA SAY FROM FROM HOULTON DOWN INTO HANCOCK
AND WASHINGTON COUNTY W/UP AROUND 0.50 INCHES. ATTM, IF THERE IS
TO BE ANY SNOWFALL ACCUMULATION, IT WILL BE ACROSS EASTERN
WASHINGTON COUNTY W/A SLUSHY INCH POSSIBLE BEFORE THINGS WIND DOWN
MONDAY MORNING. TEMPERATURES ARE FORECAST TO DROP DOWN INTO THE
LOWER 30S ACROSS EASTERN AREAS AFTER MIDNIGHT W/MID AND UPPER 20S
BACK ACROSS THE W AND NW AREAS.
THE LOW IS FORECAST TO QUICKLY LIFT ACROSS THE MARITIMES ON MONDAY
W/CAA POURING INTO THE REGION AND DRIER CONDITIONS. THERE IS SOME
CONCERN THE CLOUDS ACROSS NORTHERN AND EASTERN MAINE MIGHT HANG ON
THROUGH MONDAY W/A NNW FLOW COMING IN OFF THE OPEN ST. LAWRENCE.
THE GFS SOUNDINGS HINT AT THIS TO BE POSSIBLE W/SOME MOISTURE
SHOWING UP BELOW 3000 FT. THIS SETUP SIMILAR TO THIS SCENARIO TOOK
PLACE LAST WEEK WHEN A CLOUD DECK BELOW 2500 FT HUNG ON LONGER
THAN ANTICIPATED. TEMPERATURES ON MONDAY WILL BE HELD DOWN INTO
THE 30S W/CLOUDS AND A NNW WIND OF 10 TO 20 MPH.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A NNW WIND AND CLOUDS LOOK TO HANG ON ESPECIALLY FOR NORTHERN AND
EASTERN AREAS MONDAY NIGHT W/CAA CONTINUING TO POUR INTO THE
REGION. ANOTHER ITEM TO BE AWARE OF WILL BE POTENTIAL FOR STREAMERS
OF LIGHT SNOW FROM THE OPEN ST. LAWRENCE FOR PORTIONS OF NORTHERN
AND EASTERN MAINE. THE MODEL GUIDANCE TENDS TO HAVE A DIFFICULT
TIME IN PICKING UP THIS MESO-SCALE FEATURE. THE HRRR MODEL AND
NAM12 TEND TO CATCH ON AS WE CLOSE IN CLOSER TO THE EVENT.
CONTINUED BREEZY AND COLD ON TUESDAY W/SOME PARTIAL CLEARING
ACROSS NORTHERN MAINE AS HIGH PRES STARTS TO MOVE IN FROM THE W.
DOWNEAST AND THE COAST SHOULD SEE A DECENT AMOUNT OF SUNSHINE.
DAYTIME TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL FOR LATE
NOVEMBER.
STRONG HIGH PRES IS FORECAST TO BUILD ACROSS THE REGION TUESDAY
NIGHT INTO WEDNESDAY AND THEN LIFT TO THE NE INTO THE NW ATLC ON
THANKSGIVING DAY. THIS WILL MEAN DRY TRAVEL WEATHER FOR THE
THANKSGIVING HOLIDAY W/MODERATING TEMPERATURES.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: EXPECT VFR CONDITIONS TODAY AND TONIGHT.
SHORT TERM: IFR/MVFR CONDITIONS FOR SUNDAY W/IFR MAINLY FROM KHUL
TO KBHB. MVFR FOR THE REMAINDER OF THE TAF SITES THROUGH SUNDAY
EVENING. CONDITIONS EXPECTED TO IMPROVE TO VFR FOR KBGR AND KBHB
FRO MONDAY WHILE THE NORTHERN TAF SITES COULD SEE PERIODS OF MVFR
CIGS. ATTM, VFR EXPECTED FOR ALL TAF SITES FOR TUESDAY INTO
WEDNESDAY
&&
.MARINE...
NEAR TERM: FOR SUSTAINED WINDS HAVE USED THE NAM12. FOR WAVES:
BUOY OBSERVATIONS INDICATE LONG PERIOD INCOMING SWELL STILL
PRESENT FROM SOUTHEASTERLY FETCH EARLY FRIDAY. EXPECT THIS TO
SUBSIDE RAPIDLY EARLY TODAY WITH OFF-SHORE WIND WAVE BECOMING THE
PREDOMINATE WAVE SYSTEM. SEAS WILL SUBSIDE RAPIDLY TONIGHT ALONG
WITH WINDS WITH LONG PERIOD SOUTHEASTERLY WAVE SYSTEM 1-2 FEET/8
SECONDS ONCE AGAIN BECOMING PREDOMINATE.
SHORT TERM: LOOKING FOR THE POTENTIAL FOR SCA CONDITIONS TO
DEVELOP SUNDAY NIGHT INTO MONDAY ESPECIALLY FOR THE OUTER ZONES.
WINDS ARE EXPECTED TO INCREASE TO 15 TO 20 KT W/GUSTS OF 25 KTS
AND A SWELL GENERATION TAKING PLACE ALLOWING FOR SEAS TO BUILD TO
5 TO 7 FT. AS A MATTER OF FACT, SCA CONDITIONS COULD HANG ON RIGHT
INTO MONDAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE LOW PASSING
ACROSS THE MARITIMES AND STRONG HIGH PRES MOVING IN FROM THE W.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR
ANZ050>052.
&&
$$
NEAR TERM...MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...MIGNONE/HEWITT
MARINE...MIGNONE/HEWITT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1120 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 826 PM CST FRI NOV 20 2015
FORECAST WAS UPDATED TO CLEAR HEADLINES...AND REMOVE ALL MENTION
OF PRECIPITATION TONIGHT EXCEPT FOR WHAT IS STILL MOVING THROUGH
THE FAR SOUTHEAST CORNER OF THE FORECAST AREA...BUT EVEN THAT
SHOULD BE DONE SOON. ALSO ADJUSTED TEMPERATURES AND WINDS FOR
TONIGHT BASED ON LATEST OBSERVATIONS. A FEW FLURRIES MAY STILL BE
REPORTED THIS EVENING BUT NO REDUCTIONS TO VISIBILITY EXPECTED.
AT 0230Z THERE WAS ANOTHER SMALL BAND OF VERY LIGHT SNOW OVER THE
NEBRASKA PANHANDLE WITH CHADRON DOWN TO 1.25 MI AND 1 MILE AT
SCOTTS BLUFF. THE 01Z RUNS OF THE THE OPERATIONAL AND
EXPERIMENTAL HRRR BRING THIS LIGHT BAND INTO NORTH CENTRAL-SOUTHWEST
NEBRASKA BY 09Z. THESE MODELS INDICATE THAT BAND SHOULD DISSIPATE
BEFORE MOVING INTO EASTERN NEBRASKA...BUT WE WILL KEEP ON EYE ON
THE TRENDS.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 230 PM CST FRI NOV 20 2015
SNOW CONTINUES TO FALL ACROSS NORTHERN PARTS OF THE AREA EARLY
THIS AFTERNOON WITH HIGHEST AMOUNTS REPORTED ALONG THE NORTHERN
BORDER WHERE SNOW HAS BEEN PERSISTENT SINCE THIS MORNING. LATEST
REGIONAL RADARS SHOW BACK EDGE OF SNOW MOVING QUICKLY EAST INTO
NORTHEAST NEBRASKA AT 19Z WITH COLD FRONT PUSHING SOUTH TOWARD
SOUTHEAST NEBRASKA. MAIN SNOW BAND HAS BEEN ORIENTED ALONG
600-700MB AXIS OF FRONTOGENETIC FORCING SINCE THIS MORNING WITH A
SECONDARY BAND OF PRECIP OVER SOUTHWEST IOWA ALONG THE 800-900MB
AXIS. LATEST SHORT RANGE MODELS SHOW THE MID LEVEL FORCING
BECOMING LESS FOCUSED ALONG THE NORTHERN BORDER AND DRIFTING TO
THE SOUTHEAST THROUGH THE EVENING WHILE LOW LEVEL FORCING DROPS
INTO KANSAS AND MISSOURI AS THE COLD AIR MOVES INTO THE AREA.
WILL CONTINUE WITH CURRENT HEADLINES FOR NOW SINCE WINDS WILL BE
PICKING UP BEHIND THE FRONT. CURRENT SNOW AMOUNTS AND ORIENTATION
ALSO LOOKS PRETTY GOOD WITH AMOUNTS DROPPING OFF QUICKLY SOUTH OF
THE PLATTE RIVER INTO SOUTHWEST CORNER OF IOWA. SYSTEM SHOULD BE
PRETTY MUCH OUT OF THE AREA BY MID TO LATE EVENING.
A PERIOD OF DRY WEATHER FOLLOWS BEHIND THIS SYSTEM FOR SATURDAY INTO
MONDAY. COLD TEMPERATURES WILL BE THE RULE THROUGH SUNDAY MORNING
THEN MODERATING A BIT INTO EARLY NEXT WEEK.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 230 PM CST FRI NOV 20 2015
FIRST PART OF THE WEEK STARTS OFF SEASONAL AND DRY BUT ANOTHER
STORM SYSTEM FROM MID TO LATE WEEK WILL BRING THE CHANCE OF MORE
WINTER WEATHER TO A LARGE PART OF THE REGION FOR THE THANKSGIVING
HOLIDAY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1120 PM CST FRI NOV 20 2015
WINDS WILL SLOWLY DECREASE OVERNIGHT. CURRENT CIGS FROM 1000 TO
2000 FEET WILL LIFT AND BECOME VFR. STILL SOME POTENTIAL FOR SOME
FLURRIES OVERNIGHT BUT GENERALLY SHOULD NOT RESTRICT VSBY BELOW
6 MILES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...NIETFELD
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1107 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 655 PM CST FRI NOV 20 2015
SENT AN UPDATE OUT FOR THIS EVENING...CURTAILING SNOW EARLIER BY 9
AM FOR ALL AREAS AS THE HRRR SEEMS TO HAVE THE BEST GRIP ON LATEST
PRECIPITATION TRENDS AS WELL AS THE RADAR INDICATING THAT MOST
PRECIPITATION IS OUT OF OUR CWA.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 319 PM CST FRI NOV 20 2015
THE MAIN CONCERNS IN THE SHORT TERM FORECAST PERIOD ARE ACTUALLY IN
THE VERY NEAR TERM AS A LARGE UPPER LEVEL DISTURBANCE IS BRINGING
ONGOING PRECIPITATION TO PORTIONS OF NEBRASKA. OTHERWISE THE
REMAINDER OF SHORT TERM IS FAIRLY QUIET AND SEASONABLY COLD.
FOR THE REST OF TODAY...THE UPPER LEVEL TROUGH WILL CONTINUE TO
SURGE EASTWARD ACROSS THE PLAINS...AS A DAUNTING COLD FRONTAL
BOUNDARY SINKS QUICKLY SOUTHEAST. LATEST RADAR TRENDS HAS INDICATED
POCKETS OF HEAVIER PRECIPITATION REMAINING WELL TO THE NORTH OF
INTERSTATE 80 WITH ONLY LIGHT SCATTERED RADAR RETURNS ACROSS THE TRI-
CITIES. OBSERVATIONS AROUND MID AFTERNOON SHOW THE FRONTAL BOUNDARY
HAS SAGGED AS FAR SOUTH AS THE TRI-CITIES. FORECAST SNOW AMOUNTS
COULD BE A BIT HIGH FOR PORTIONS OF POLK COUNTY THIS EVENING.
CHANCES FOR PRECIPITATION WILL LAST THE LONGEST FOR THAT COUNTY AS
THE SYSTEM EXITS. HOWEVER...TEMPERATURES WILL NEED TO WET BULB DOWN
CLOSER TO FREEZING FOR SNOW TO MATERIALIZE. THIS HAPPENED RATHER
QUICKLY ACROSS PORTIONS OF VALLEY AND GREELEY COUNTIES BUT
CONFIDENCE IS RATHER SHAKY FURTHER SOUTHEAST. THUS SNOW AMOUNTS MAY
ACTUALLY BE LOWER THAN FORECAST.
THE COLD FRONT WILL CONTINUE TO SURGE SOUTH THIS EVENING WITH STRONG
NORTHERLY WINDS BEHIND THE FRONT. THIS INCREASED GUSTS COULD LAST
WELL INTO THE OVERNIGHT HOURS BEFORE DECREASING NEAR SUNRISE.
THE FRONT WILL USHER IN MUCH COLDER AIR...IN FACT...PROBABLY THE
COLDEST OF THE SEASON SO FAR. HIGH TEMPERATURES TOMORROW WILL
STRUGGLE TO REACH THE MID TO UPPER 30S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 319 PM CST FRI NOV 20 2015
A COLD SURFACE HIGH PRESSURE SYSTEM WILL SLIDE TO THE SOUTHEAST
SATURDAY NIGHT. TEMPERATURES WILL CONTINUE TO BE COLD SATURDAY
NIGHT. BY SUNDAY MORNING THE WINDS ARE TURNING TO THE WEST AND WITH
WARM ADVECTION AND DOWN SLOPE WINDS...TEMPERATURES SHOULD RECOVER
PRETTY EASILY INTO THE MID 40S TO AROUND 50. WILL HAVE TO WATCH TO
SEE HOW MUCH SNOW FALLS THIS AFTERNOON AND IF IT WILL HAVE ANY
EFFECT ON THE TEMPERATURES ON SUNDAY.
SUNDAY NIGHT THROUGH TUESDAY A WEAK UPPER LEVEL RIDGE MOVES OVER THE
AREA. THE SURFACE HIGH MOVES TO THE EAST AND A SURFACE LOW DEVELOPS
ON THE HIGH PLAINS. WITH WARM ADVECTION AND WINDS TURNING FROM WEST
TO SOUTH...WILL CONTINUE WITH THE WARM TEMPERATURES. READINGS IN THE
50S ARE POSSIBLE DURING THE DAY.
AN UPPER LEVEL WAVE STARTS TO APPROACH THE FORECAST AREA TUESDAY
NIGHT INTO WEDNESDAY. WITH THE SOUTH WINDS ACROSS THE AREA MONDAY
AND TUESDAY THERE IS SOME MOISTURE THAT MOVES NORTH INTO THE
AREA...MOSTLY IN THE EAST. BY WEDNESDAY THE UPPER WAVE IS AFFECTING
THE AREA ENOUGH THAT WITH THE MOISTURE...THERE IS A SMALL CHANCE FOR
SOME LIGHT RAIN...MAINLY NORTH AND EAST IN THE AREA. A COLD FRONT
MOVES INTO THE AREA WEDNESDAY AFTERNOON AND EVENING. THE COLD AIR IS
A LITTLE BEHIND THE FRONT AND DURING THE AFTERNOON EXPECT RAIN.
THE UPPER LEVEL WAVE MOVES INTO THE AREA WEDNESDAY NIGHT AND THE
COLD FRONT MOVES TO THE SOUTH. BY WEDNESDAY NIGHT THE TEMPERATURES
START TO COOL OFF ENOUGH THAT THE PRECIPITATION SHOULD MIX WITH SNOW
FOR MUCH OF THE AREA THEN CHANGE TO SNOW IN THE NORTHWEST. THE
NORTHWEST SHOULD BE COLD ENOUGH DURING THE DAY THURSDAY TO KEEP
SNOW...BUT PORTIONS OF THE AREA COULD HAVE A MIX WITH MOSTLY RAIN IN
THE SOUTHEAST. COLDER AIR CONTINUES TO PUSH INTO THE AREA AND HAVE A
CHANCE FOR SNOW BOTH THURSDAY NIGHT AND FRIDAY. THAT IS THE CURRENT
THINKING. THE ONE MAIN WRENCH IN ALL OF THIS IS THERE IS A TIGHT
TEMPERATURE GRADIENT AT 850MB AS IT MOVES THROUGH THE AREA. THE
CHANGE FROM RAIN TO SNOW COULD CHANGE QUITE A BIT AS THE COLD AIR
COMES IN. ALSO...IF THE TIMING IS OFF A LITTLE BIT IT COULD MAKE
PHASE CHANGE TIMING DIFFERENT AS WELL.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1055 PM CST FRI NOV 20 2015
NORTH WINDS WILL BE GUSTY FOR THE MAJORITY OF THE NIGHT BEFORE
SUBSIDING TOWARDS DAYBREAK ON SATURDAY AS THE SFC GRADIENT RELAXES
AS HIGH PRESSURE SETTLES ONTO THE PLAINS. CANNOT COMPLETELY RULE
OUT A FLURRY POTENTIAL BRIEFLY TONIGHT BUT CHCS ARE FAIRLY
MINIMAL. MVFR CIGS WILL INCREASE TO VFR SATURDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HEINLEIN
SHORT TERM...SALTZMAN
LONG TERM...JCB
AVIATION...FAY
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
148 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL RAPIDLY MOVE OVER AND THEN EAST OF OUR AREA
OVERNIGHT AS A FAST WAVE AND COLD FRONT APPROACHES FROM THE WEST
SATURDAY AFTERNOON. THIS WILL TRIGGER RAIN TO SNOW SHOWERS
OVERNIGHT SATURDAY INTO SUNDAY AND POSSIBLE LAKE EFFECT SNOW IN
NORTHWEST PENNSYLVANIA SUNDAY INTO SUNDAY NIGHT. IT WILL BE A TAD
COLDER THEN NORMAL SUNDAY-MONDAY. A RIDGE WILL BUILD TO OVER THE
CENTRAL US TUESDAY INTO THANKSGIVING PROVIDING A RELATIVELY DRY
PERIOD AND WARMING TREND. DEEP SOUTHWESTERLY FLOW LATE NEXT WEEK
COULD BRING A CHANCE OF RAIN/RAIN SHOWERS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
03Z IR LOOP SHOWING MID/HIGH LVL CLOUDINESS MOVING INTO CENTRAL
PA...AS WAA ALOFT OVERSPREADS THE REGION AHEAD OF SHORTWAVE OVR
THE PLAINS STATES. LATEST NEAR TERM MDL DATA SUGGESTS THE CLOUD
COVER WILL BE THICKEST ARND 06Z...THEN THIN OUT AND PUSH NORTHEAST
OF THE AREA TOWARD DAWN. THE LGT WIND AND VERY DRY AIR ASSOC WITH
SFC HIGH PRES WILL ALLOW TEMPS TO FALL INTO THE 20S FOR MOST OF
THE AREA. LATEST HRRR TIMESERIES SHOW TEMPS BOTTOMING OUT ARND
04Z...RISING A BIT AS CLOUDS ARRIVE...THEN REACHING A SECOND MIN
AT DAWN.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
RIDGE OF HIGH PRES ALONG THE E COAST SHOULD ENSURE A DRY SATURDAY
ACROSS CENTRAL PA. LIGHT WINDS EXPECTED FOR MOST...ALTHOUGH THE
HIGHER ELEVATIONS OF THE ALLEGHENY HIGHLANDS WILL SEE SOME
INCREASING SOUTHEAST BREEZES IN THE AFTERNOON. BUFKIT SUPPORTS
AFTN GUSTS BTWN 20-25KTS.
LATEST MDL DATA INDICATES 8-7H BAROCLINIC ZONE AND ASSOC MID LVL
CLOUDINESS WILL SHIFT NORTH OF PA ON SATURDAY. WILL MAINTAIN MCLDY
SKIES FOR NOW ACROSS THE N MTNS. HOWEVER...MUCH OF CENTRAL PA
SHOULD EXPERIENCE A MSUNNY SATURDAY. ENS MEAN 925MB TEMPS NR 2C
SHOULD BE SUPPORTIVE OF MAX TEMPS BTWN 45-50F.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A FAST MOVING WAVE AND STRONG COLD FRONT WILL TRIGGER SOME LIGHT
RAIN WHICH WILL TURN TO SNOW QUICKLY IN THE NORTHWESTERN AREAS
SATURDAY NIGHT. FARTHER EAST VERY LIGHT RAIN LIKELY ENDING AS
SNOW SHOWERS OR FLURRIES SUNDAY. IT WILL TURN MARKEDLY COLDER
EARLY SUNDAY AND BREEZY.
THE COLD AIR...WARM LAKES AND WESTERLY WINDS INDICATE A POTENTIAL
ERIE SNOW BAND. AT THIS TIME SREF IS SUGGESTING 2-4 INCHES
POSSIBLE NEAR NY BORDER...BUT BEST SNOW IS LIKELY TO THE NORTH OF
THE PA/NY BORDER. WE WILL WAIT TO SEE 3KM NCAR ENSEMBLE TONIGHT
AND HOW IT FORECASTS THE SNOW. WE SHOWED GENERALLY 1-3 INCHES AT
THIS TIME IN THE LES EVENT AND WILL WAIT FOR HIGHER RESOLUTION
GUIDANCE.
SUNDAY WILL BE COLD AND BREEZY. THE COLD AIR SHOULD SLOWLY EASE ON
MONDAY INTO MONDAY NIGHT. WE BOTTOM OUT -1 TO -1.5SD BELOW NORMAL
FOR 850 MB TEMPS SUNDAY INTO MONDAY EVENING.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT...
ISSUED AT 120 AM EST SAT NOV 21 2015...
VFR WILL CONTINUE TODAY WITH SOME DETERIORATION IN FLYING
CONDITIONS EXPECTED LATER SATURDAY NIGHT INTO EARLY SUNDAY. SFC
WINDS FROM 100-150 DEGREES WILL INCREASE AS LOW PRESSURE
INTENSIFIES TRACKING ENEWD FROM THE LOWER OH VALLEY INTO THE LOWER
GREAT LAKES. ADDED LLWS TO THE WESTERN TAFS DUE TO 40-50KT
SOUTHERLY LOW LEVEL FLOW IN ADVANCE OF THE LOW AND TRAILING COLD
FRONT. RAIN SHOWERS SHOULD REACH THE WESTERN 1/3 OF THE AIRSPACE
BY 06Z SATURDAY AND EVENTUALLY TRANSITION TO -SHSN WITH IFR VIS
POSSIBLE AT BFD.
OUTLOOK...SUNDAY-WEDNESDAY
SUN...MVFR CIGS WEST TO VFR EAST. IFR VIS PSBL NW IN SHSN.
MON...MVFR/VFR CIGS WEST. VFR CENTRAL/EAST. NO SIG WX.
TUE...MVFR WITH CHC -SHSN NW. VFR/NO SIG WX ELSEWHERE.
WED...VFR/NO SIG WX.
&&
.CLIMATE...
ISSUED AT 148 AM EST SAT NOV 21 2015
WITH 10 DAYS LEFT IN THE MONTH...PRELIMINARY CLIMATE DATA
INDICATES THAT NOVEMBER 2015 IS CURRENTLY ON TRACK TO BE THE
WARMEST NOVEMBER ON RECORD AT OUR TWO LONG TERM CLIMATE SITES:
HARRISBURG AND WILLIAMSPORT. A CONTINUOUS WEATHER RECORD HAS BEEN
KEPT AT EACH SITE SINCE 1888 AND 1895 RESPECTIVELY.
THROUGH 11/20...
THE AVG. MONTHLY TEMPERATURE AT HARRISBURG IS 53.2 DEGREES OR
+7.2 DEGREES ABOVE NORMAL.
THE AVG. MONTHLY TEMPERATURE AT WILLIAMSPORT IS 50.9 DEGREES OR
+7.5 DEGREES ABOVE NORMAL.
THE TOP 5 WARMEST NOVEMBERS (CURRENT RANKINGS)
MDT: 2015 (53.2), 1931 (51.3), 1975 (50.0), 1999 (49.3), 1994
(49.0)
IPT: 2015 (50.9), 1931 (48.8), 1902 (47.3), 2009/1972 (47.2), 1913
(46.3)
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...GRUMM
AVIATION...STEINBUGL
CLIMATE...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
123 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL RAPIDLY MOVE OVER AND THEN EAST OF OUR AREA
OVERNIGHT AS A FAST WAVE AND COLD FRONT APPROACHES FROM THE WEST
SATURDAY AFTERNOON. THIS WILL TRIGGER RAIN TO SNOW SHOWERS
OVERNIGHT SATURDAY INTO SUNDAY AND POSSIBLE LAKE EFFECT SNOW IN
NORTHWEST PENNSYLVANIA SUNDAY INTO SUNDAY NIGHT. IT WILL BE A TAD
COLDER THEN NORMAL SUNDAY-MONDAY. A RIDGE WILL BUILD TO OVER THE
CENTRAL US TUESDAY INTO THANKSGIVING PROVIDING A RELATIVELY DRY
PERIOD AND WARMING TREND. DEEP SOUTHWESTERLY FLOW LATE NEXT WEEK
COULD BRING A CHANCE OF RAIN/RAIN SHOWERS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
03Z IR LOOP SHOWING MID/HIGH LVL CLOUDINESS MOVING INTO CENTRAL
PA...AS WAA ALOFT OVERSPREADS THE REGION AHEAD OF SHORTWAVE OVR
THE PLAINS STATES. LATEST NEAR TERM MDL DATA SUGGESTS THE CLOUD
COVER WILL BE THICKEST ARND 06Z...THEN THIN OUT AND PUSH NORTHEAST
OF THE AREA TOWARD DAWN. THE LGT WIND AND VERY DRY AIR ASSOC WITH
SFC HIGH PRES WILL ALLOW TEMPS TO FALL INTO THE 20S FOR MOST OF
THE AREA. LATEST HRRR TIMESERIES SHOW TEMPS BOTTOMING OUT ARND
04Z...RISING A BIT AS CLOUDS ARRIVE...THEN REACHING A SECOND MIN
AT DAWN.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
RIDGE OF HIGH PRES ALONG THE E COAST SHOULD ENSURE A DRY SATURDAY
ACROSS CENTRAL PA. LIGHT WINDS EXPECTED FOR MOST...ALTHOUGH THE
HIGHER ELEVATIONS OF THE ALLEGHENY HIGHLANDS WILL SEE SOME
INCREASING SOUTHEAST BREEZES IN THE AFTERNOON. BUFKIT SUPPORTS
AFTN GUSTS BTWN 20-25KTS.
LATEST MDL DATA INDICATES 8-7H BAROCLINIC ZONE AND ASSOC MID LVL
CLOUDINESS WILL SHIFT NORTH OF PA ON SATURDAY. WILL MAINTAIN MCLDY
SKIES FOR NOW ACROSS THE N MTNS. HOWEVER...MUCH OF CENTRAL PA
SHOULD EXPERIENCE A MSUNNY SATURDAY. ENS MEAN 925MB TEMPS NR 2C
SHOULD BE SUPPORTIVE OF MAX TEMPS BTWN 45-50F.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A FAST MOVING WAVE AND STRONG COLD FRONT WILL TRIGGER SOME LIGHT
RAIN WHICH WILL TURN TO SNOW QUICKLY IN THE NORTHWESTERN AREAS
SATURDAY NIGHT. FARTHER EAST VERY LIGHT RAIN LIKELY ENDING AS
SNOW SHOWERS OR FLURRIES SUNDAY. IT WILL TURN MARKEDLY COLDER
EARLY SUNDAY AND BREEZY.
THE COLD AIR...WARM LAKES AND WESTERLY WINDS INDICATE A POTENTIAL
ERIE SNOW BAND. AT THIS TIME SREF IS SUGGESTING 2-4 INCHES
POSSIBLE NEAR NY BORDER...BUT BEST SNOW IS LIKELY TO THE NORTH OF
THE PA/NY BORDER. WE WILL WAIT TO SEE 3KM NCAR ENSEMBLE TONIGHT
AND HOW IT FORECASTS THE SNOW. WE SHOWED GENERALLY 1-3 INCHES AT
THIS TIME IN THE LES EVENT AND WILL WAIT FOR HIGHER RESOLUTION
GUIDANCE.
SUNDAY WILL BE COLD AND BREEZY. THE COLD AIR SHOULD SLOWLY EASE ON
MONDAY INTO MONDAY NIGHT. WE BOTTOM OUT -1 TO -1.5SD BELOW NORMAL
FOR 850 MB TEMPS SUNDAY INTO MONDAY EVENING.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT...
ISSUED AT 120 AM EST SAT NOV 21 2015...
VFR WILL CONTINUE TODAY WITH SOME DETERIORATION IN FLYING
CONDITIONS EXPECTED LATER SATURDAY NIGHT INTO EARLY SUNDAY. SFC
WINDS FROM 100-150 DEGREES WILL INCREASE AS LOW PRESSURE
INTENSIFIES TRACKING ENEWD FROM THE LOWER OH VALLEY INTO THE LOWER
GREAT LAKES. ADDED LLWS TO THE WESTERN TAFS DUE TO 40-50KT
SOUTHERLY LOW LEVEL FLOW IN ADVANCE OF THE LOW AND TRAILING COLD
FRONT. RAIN SHOWERS SHOULD REACH THE WESTERN 1/3 OF THE AIRSPACE
BY 06Z SATURDAY AND EVENTUALLY TRANSITION TO -SHSN WITH IFR VIS
POSSIBLE AT BFD.
OUTLOOK...SUNDAY-WEDNESDAY
SUN...MVFR CIGS WEST TO VFR EAST. IFR VIS PSBL NW IN SHSN.
MON...MVFR/VFR CIGS WEST. VFR CENTRAL/EAST. NO SIG WX.
TUE...MVFR WITH CHC -SHSN NW. VFR/NO SIG WX ELSEWHERE.
WED...VFR/NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...GRUMM
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
302 AM EST SAT NOV 21 2015
.SHORT TERM (TODAY AND TONIGHT)...
TRANQUIL WEATHER CONDITIONS ACROSS THE AREA EARLY THIS MORNING.
CURRENT WATER VAPOR IMAGERY AND RAP UPPER AIR ANALYSIS INDICATES A
LARGE SCALE TROUGH ACROSS THE CENTRAL CONUS. AT THE SURFACE...HIGH
PRESSURE IS IN PLACE ACROSS THE MID-ATLANTIC WITH A SURFACE LOW
CURRENTLY ACROSS SOUTHERN MISSOURI WITH A COLD FRONT TRAILING INTO
THE SOUTHERN PLAINS. TEMPERATURES SHOULD WARM QUICKLY INTO THE MID
50S BY LATE THIS MORNING AS THE SURFACE LOW TRACKS TO THE NORTH OF
THE AREA THIS AFTERNOON. MOISTURE RETURN WITH THE SYSTEM WILL NOT
BE OVERLY IMPRESSIVE. IT WILL TAKE SOME TIME BEFORE LOW LEVEL WINDS
SWITCH AROUND TO THE SOUTH WITH THE SURFACE HIGH TO THE NORTHEAST.
THIS DELAY WILL CREATE A BRIEF AND NARROW WINDOW OF DEWPOINTS IN
THE 40S AND PW VALUES IN THE 0.75-0.85 INCH RANGE. THESE VALUES ARE
A BIT ABOVE NORMAL FOR THIS TIME OF YEAR...BUT AGAIN THIS MOISTURE
IS NOT EXPECTED TO LAST LONG. HAVE CONTINUED WITH THE HIGHEST POPS
AFTER 3PM WITH THE MOISTURE BEING LIMITED TO RIGHT ALONG THE
FRONTAL BOUNDARY. THE COLDEST AIR OF THE SEASON WILL MOVE IN BEHIND
THE FRONT LATE THIS EVENING INTO THE OVERNIGHT HOURS. ALL OF THE
MODELS INDICATE ENOUGH MOISTURE HANGING AROUND FOR A FEW LIGHT SNOW
SHOWERS/FLURRIES ACROSS THE HIGHER TERRAIN. AGAIN...MOISTURE IS
EXTREMELY LIMITED BUT THERE WILL BE SOME OROGRAPHIC LIFT WITH
LIMITED LOW LEVEL MOISTURE IN PLACE. IT APPEARS THE BEST TIME FOR
SNOW IN THE HIGH TERRAIN WILL BE FROM 06-12Z SUNDAY. THERE COULD
BE SOME MINOR ACCUMULATIONS OF UP TO HALF AN INCH IN THE HIGHEST
TERRAIN LATE TONIGHT INTO EARLY TOMORROW MORNING.
.LONG TERM (SUNDAY THROUGH FRIDAY)...
THE EXTENDED BEGINS WITH VERY COLD AIR MOVING INTO THE SOUTHERN
APPALACHIAN REGION. HIGHS ON SUNDAY WILL STRUGGLE TO REACH INTO THE
40S ACROSS THE TN VALLEY...WITH ONLY 30S OVER THE MOUNTAINS. COLD
AIR CONTINUES TO PUSH IN SUNDAY NIGHT WITH LOWS FALLING INTO THE
TEENS IN THE MOUNTAINS AND 20S ACROSS LOWER VALLEY LOCATIONS.
TEMPERATURES WILL SLOWLY BEGIN TO MODERATE ON MONDAY AS FLOW ALOFT
BEGINS LESS NORTHERLY. HOWEVER...THE WARMING TREND WILL BEGIN IN
EARNEST TUESDAY AND WEDNESDAY AS UPPER FLOW BECOME ZONAL. BY
THURSDAY AND FRIDAY...AN UPPER RIDGE BUILDS INTO THE REGION
ALLOWING DAYTIME HIGHS TO ONCE AGAIN REACH INTO THE 60S ACROSS MUCH
LOWER ELEVATIONS. OVERALL...WE WILL BE IN A QUIET WEATHER PATTERN
WITH DRY CONDITIONS EXPECTED THROUGHOUT THE EXTENDED. ONLY CONCERN
WILL BE AN APPROACHING WEATHER SYSTEM ON FRIDAY. CURRENT MODEL RUNS
BEGIN TO BRING MID AND HIGH CLOUDS IN BY FRIDAY BUT FOR NOW KEEP
ASSOCIATED PRECIP TO THE WEST UNTIL AFTER THE EXTENDED PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 59 33 46 27 / 20 20 0 0
KNOXVILLE MCGHEE TYSON AIRPORT, TN 60 33 43 23 / 20 40 10 0
OAK RIDGE, TN 60 33 42 23 / 30 30 0 0
TRI CITIES AIRPORT, TN 58 32 41 20 / 10 40 10 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
MA/MJB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1118 PM CST FRI NOV 20 2015
.UPDATE...
ISSUED AT 740 PM CST FRI NOV 20 2015
LOOKING A LOT MORE LIKE LATE NOVEMBER OUT THERE...AT LEAST FOR
PARTS OF THE AREA. NICE TO SEE THAT THIS STORM SYSTEM OVERALL IS
UNFOLDING AS EXPECTED THE PAST 24-36 HOURS...WITH INCOMING AMOUNTS
ACROSS MUCH OF THE CURRENT WARNING AREA MAINLY IN THE 4-7 INCH
RANGE SO FAR...HEAVIEST OF COURSE WHERE INDIVIDUAL STRONGER FGEN
BANDED ELEMENTS HAVE LAID OUT THE LONGEST...PRIMARILY SOUTH OF
HIGHWAY 18. FARTHER NORTH...AMOUNTS HAVE TAPERED CONSIDERABLY...
GENERALLY ONLY PUSHING AN INCH OR TWO ALONG THE IA/MN BORDER PER
REPORTS...AND ONLY A DUSTING TO PERHAPS A HALF INCH JUST SOUTH OF
THE I-90 CORRIDOR. THESE AMOUNTS ARE PRETTY MUCH IN LINE WITH
EARLIER THINKING..
DON`T PLAN ANY BIG CHANGES TO GOING HEADLINES...THOUGH MAY
ULTIMATELY HAVE TO DITCH THE WARNING FOR RICHLAND COUNTY PER RADAR
TRENDS...AS THE STRONGER FGEN BAND HAS REALLY WEAKENED OVER THAT
AREA THE PAST HOUR OR TWO. ALSO...WILL LIKELY NEED TO SPEED UP THE
EXIT TIME OF WIDESPREAD PRECIP PER RADAR TRENDS...THOUGH WITH THE
ARRIVAL OF THE ACTUAL UPPER WAVE...WE MAY TEND TO SEE SOME
REDEVELOPMENT WITHIN AN ELONGATING MID LEVEL DEFORMATION AXIS INTO
FAR SOUTHWEST WISCONSIN AND NORTHEAST IOWA. REGARDLESS OF THE
ACTUAL TIME...CURRENT HEADLINES DO COVER THE BIGGER ISSUE...WHICH
HAS BEEN IMPACT WITH QUITE A FEW REPORTS OF ACCIDENTS...CERTAINLY
NOT HELPED BY THE FACT THAT THIS IS THE FIRST EVENT OF THE SEASON.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
HAVE BEEN TRYING TO INTEGRATE CURRENT RADAR AND SURFACE
OBSERVATIONS INTO THE FORECAST TO FINE TUNE STORM. BOTTOM LINE IS
THE ADVISORIES AND WARNINGS LOOK ON TRACK FOR LOCATION. WE DID
UPDATE THE START TIME. HAVE LEFT THE END TIME ON SATURDAY AS THE
NORTHWEST WINDS OF 15 TO 25 MPH WILL CAUSE SOME DRIFTING...
ESPECIALLY ON THE HIGHER TERRAIN OF SWRN WI AND NERN IA.
CURRENT SNOW BAND IS IMPRESSIVE WITH AMOUNTS NEAR 15 INCHES NEAR
SIOUX FALLS SD TODAY AND MESSY ROADS EXTENDING NOW INTO PARTS OF
NERN IA UNDER THE SNOW BAND. GIVEN A MODERATE SNOW
RATE IN THE CENTRAL-EASTERN IA SNOW BAND...ACCUMULATING SNOW AND
SLICK ROADS HAPPEN FAIRLY QUICK AFTER ONSET. THIS BAND IS WELL
REPRESENTED BY 600-700 MB FRONTOGENESIS FORCING PER RAP ANALYSIS.
THE BAND SHOULD CONTINUE TO SHIFT NORTHEAST THROUGH EARLY EVENING. PER
VIGOROUS SHORTWAVE TROUGH IN KS/NEB MOVING AT US...THE
FRONTOGENESIS THEN REINVIGORATES A BIT LATER EVENING ON A NE-SW
ARC OVER THE SOUTHERN FORECAST AREA...WITH THE MAIN HEAVY SNOW
BAND NEAR HIGHWAY 20 TO I-80 WITH STRONGER FRONTOGENESIS INDICATED
IN THE SHORT TERM MODELS.
BIG PICTURE REMAINS THE SAME FOR THIS STORM. WE HAVEN`T CHANGED
THE TOTAL LIQUID FROM THIS STORM MUCH...BUT DO HAVE SOME CONCERNS
WITH SNOW RATIOS IN THE WARNING...ESPECIALLY CLOSER TO DUBUQUE AND
THE SOUTHERN HALF OF THE FAYETTE-CLAYTON-GRANT COUNTIES. THE
LATEST RAP AND 20.12Z NAM/GFS OUTPUT RUN THROUGH THE DENDRITIC
GROWTH ZONE COBB TECHNIQUE SUGGEST RATIOS COULD BE IN THE 20-24 TO
1 RANGE. WE HAVE INCREASED THOSE RATIOS TO 17 TO 1 ACROSS THE
WARNING WITH A 150-200 MB DENDRITE GROWTH ZONE SUGGESTED. THIS
RAISES TOTALS TOWARD A FOOT. WINDS WILL INCREASE ACROSS THE SOUTH
INTO THE 15 TO 25 MPH RANGE SATURDAY FOR A BIT OF DRIFTING SNOW.
MAIN MESSAGE IS THE SAME...WITH POSSIBLY A BIT MORE IMPACT ACROSS
THE FAR SOUTH /IA HIGHWAY 3/ WITH 10-12 INCHES AND SOME DRIFTING
SNOW. BELIEVE ACCUMULATING SNOW WILL REALLY BE SOUTH OF I-90...AND
THE HAZARDS LOOK LIKE THEY ARE PLACED WELL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 217 PM CST FRI NOV 20 2015
NORTHWEST FLOW CONTINUES WITH A COLD WEEKEND. CONSENSUS
DETERMINISTIC MODEL RUNS FROM 20.12Z AGREED WELL ON A DYNAMIC
SYSTEM SHIFTING THROUGH NERN WI RAPIDLY SUNDAY NIGHT. THIS LOOKS
LIKE IT COULD SPREAD SOME SNOW ACROSS NORTHCENTRAL WI...LEAVING BY
MONDAY.
THE WEEK THEN BEGINS TO WARM AS ANOTHER LONGWAVE TROUGH DIGS IN
THE WEST. BY MID-WEEK PRECIPITATION WORKS INTO THE AREA ON A
MOIST FLOW. A CLOUDY PERIOD WITH POSSIBLY PRECIPITATION TYPE
ISSUES. AT THIS TIME IT APPEARS MAINLY LIKE A RAIN/SNOW SCENARIO
BUT DEPENDING ON HOW MOISTURE ARRIVES...SOME FREEZING DRIZZLE
COULD BE AROUND. THE MAIN IDEA NOW IS WARMING AND PRECIPITATION BY
MID-WEEK INTO THANKSGIVING. CONFIDENCE MODERATE WITH GOOD
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1118 PM CST FRI NOV 20 2015
SNOW WILL WIND DOWN FROM WEST TO EAST FOR BOTH KRST AND KLSE
THROUGH 07Z...LEAVING LINGERING MID CLOUDS FOR A TIME BEFORE
THINGS CLEAR BY SUNRISE. HOWEVER...THERE REMAINS CONSIDERABLE
QUESTIONS ABOUT JUST HOW MUCH ADDITIONAL STRATOCUMULUS WE MIGHT BE
ABLE TO MUSTER UP HEADING INTO MIDDAY AND THE AFTERNOON...WITH
QUITE CHILLY AIR ALOFT BUT DRYING DOWN LOW. UPSTREAM CLOUD TRENDS
ARE SOMEWHAT TELLING...WITH A STEADY SOUTHWARD EXPANSION OF LOWER
STRATUS. HOWEVER...ARRIVAL OF THAT STUFF DURING PEAK HEATING (SUCH
AS IT IS IN LATE NOVEMBER) DOES SUGGEST THINGS WILL REMAIN MORE
SCATTERED AT THIS TIME. DEFINITELY SOMETHING TO WATCH CLOSELY FOR
AVIATION INTERESTS...AS ANY CEILING TODAY WILL LIKELY BE MVFR.
OTHERWISE...A RETURN TO CLEAR SKIES IS EXPECTED TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR WIZ054-055-061.
WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR WIZ053.
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST SATURDAY FOR MNZ096.
IA...WINTER STORM WARNING UNTIL 6 AM CST SATURDAY FOR IAZ008-009-018-
019.
WINTER STORM WARNING UNTIL NOON CST SATURDAY FOR IAZ010-011-029-
030.
&&
$$
UPDATE...LAWRENCE
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...LAWRENCE
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1025 PM CST FRI NOV 20 2015
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 1006 PM CST FRI NOV 20 2015
LATEST TREND OF THE HRRR SUPPORTS THE 00Z NAM TO KEEP THE ACCUM
SNOW FURTHER SOUTH. WILL CANCEL THE ADVISORY.
UPDATE
ISSUED AT 915 PM CST FRI NOV 20 2015
TREND OF THE LAST FEW HOURS INDICATE A SOUTHERN SHIFT WITH THE
HEAVY SNOW BAND OVER SOUTHERN WISCONSIN. GRB SOUNDING THIS
EVENING SUGGESTS A LOT OF DRY AIR TO OVERCOME. BEST 850-700 FGEN
REGION WELL SOUTH. NORMALLY WOULD DROP THE ADVISORY WITH AMOUNTS
MINIMAL...BUT NEED TO CONSIDER THE FIRST SNOW OF THE SEASON.
THE 00Z NAM INDICATES A DIRECTION OF DROPPING THE ADVISORY...WILL
TRY TO TAKE A QUICK PEAK AT THE EARLY PART OF THE GFS THE NEXT
HOUR...AND GO FROM THERE. WE DO HAVE THE UPPER TROUGH DROPPING IN
TONIGHT INTO SATURDAY WHICH COULD PIVOT THE LIGHTER SNOW NORTH A
BIT...BUT THIS SYSTEM IS ALSO TRACKING A BIT FASTER.
&&
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 242 PM CST FRI NOV 20 2015
PRIMARY FOCUS TO BE ON THE SNOW POTENTIAL OVER SRN SECTIONS OF THE
FCST AREA LATE TNGT/SAT MORNING AS A SYSTEM PASSES BY TO OUR
SOUTH. MODEL INCONSISTENCY HAS BEEN A PROBLEM ALL WEEK...BUT IT
NOW APPEARS THAT THE 12Z RUN HAS AT LEAST TRIED TO ZERO ON A
TRACK/NRN EDGE OF SNOW. A SECONDARY FOCUS TO BE ON INCREASING LK
EFFECT FOR N-CNTRL WI AS WINDS GRADUALLY SHIFT TO THE NW AND COLD
AIR FLOWS OVER LK SUPERIOR.
THE 20Z MSAS SFC ANALYSIS SHOWED AN AREA OF HI PRES OVER THE OHIO
RIVER VALLEY WITH STRONG LOW PRES OVER HUDSON BAY AND WEAK LOW
PRES OVER THE CNTRL HI PLAINS. RADAR MOSAIC INDICATED A NARROW...
BUT INTENSE BAND OF SNOW OVER SE SD...NE NEBRASKA AND NRN IA.
SNOWFALL RATES WITHIN THIS INTENSE BAND WERE 2-3" PER HOUR!
EVEN AT THIS LATE DATE...THE NRN EDGE OF THE MAIN SNOW BAND WAS
NOT SET IN STONE AS THE MODELS CONTINUED TO TWEAK NORTH (NAM/GFS)
OR SOUTH (GEM). MODELS DO AGREE ON THE STRONG FRONTOGENETICAL
FORCING SIGNAL THAT RUNS FROM CNTRL IA E-NE INTO SRN WI/NRN IL
TNGT...THUS HIGHEST ACCUMULATION NUMBERS WL STAY TO OUR SOUTH.
HOWEVER...DO ANTICIPATE LIGHT ACCUMULATIONS (< 1") ALONG OUR SRN
TIER OF COUNTIES BY DAYBREAK. WE WL ALSO HAVE TO WATCH SFC WINDS
AS ANY SLIGHT VEERING TO THE NE COULD ADD TO ACCUMULATIONS OVER
MANITOWOC COUNTY.
LIGHT SNOW WL CONT OVER E-CNTRL WI THRU AT LEAST SAT MORNING AS
THE SFC LOW LIFTS NE FROM THE MID-MS VALLEY TOWARD THE ERN GREAT
LAKES AND MID-LEVEL FRONTOGENETICAL FORCING BEGINS TO SHIFT FROM
SE WI INTO LWR MI. AN ADDITIONAL INCH OR TWO OF ACCUMULATION IS
POSSIBLE OVER E-CNTRL WI...THUS PLAN ON ISSUING A WINTER WEATHER
ADVY FOR WINNEBAGO...CALUMET AND MANITOWOC COUNTIES FROM 03Z-21Z
SAT (PRIMARILY FOR SRN SECTIONS OF THESE COUNTIES). TRAILING THIS
SYSTEM IS A SHRTWV TROF THAT IS FCST TO SWEEP INTO THE WRN GREAT
LAKES ON SAT. WHILE THE BULK OF THE SYNOPTIC MOISTURE TO BE TIED
UP WITH THE INITIAL STORM...WINDS ARE EXPECTED TO TURN NW AND
INTRODUCE LK EFFECT SNOW SHWRS TO N-CNTRL WI. THERE IS A POTENTIAL
FOR AN INCH OR TWO OF ACCUMULATION...ESPECIALLY OVER THE SNOWBELT
REGION OF VILAS CNTY. MAX TEMPS TO ONLY BE IN THE MID TO UPR 20S
N-CNTRL...TO THE MID 30S E-CNTRL WI. ADD IN A NW WIND AT 10 TO 20
MPH AND WIND CHILL VALUES WL ONLY BE IN THE UPR TEENS TO LWR 20S.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 242 PM CST FRI NOV 20 2015
SEVERAL CONCERNS TO DEAL WITH INCLUDE LAKE EFFECT SNOW SHOWERS
ACROSS THE NORTH SATURDAY NIGHT INTO SUNDAY MORNING...A CLIPPER
SYSTEM SUNDAY NIGHT INTO MONDAY MORNING AND THEN ABOVE NORMAL
TEMPERATURES AND UNSETTLED WEATHER FOR THANKSGIVING DAY AND
BLACK FRIDAY.
PERUSAL OF THE BUFKIT SOUNDING OVER WESTERN LAKE SUPERIOR
SATURDAY NIGHT PRETTY IMPRESSIVE SATURDAY NIGHT. ABUNDANT
MOISTURE UP TO TEN THOUSAND FEET...EQL LEVELS OF TWELVE TO
FIFTEEN THOUSAND FEET AND LAKE TO 850MB TEMPERATURE DIFFERENCES
APPROACHING 20C. LOW LEVEL WINDS ARE NOT AS FAVORABLE...BUT
CLOSE ENOUGH TO WARRANT INCREASING SNOWFALL TOTALS FROM PREVIOUS
FORECAST. CONTEMPLATED LAKE EFFECT SNOW WATCH THINKING THE SNOW
BELT REGION OF VILAS COUNTY COULD SEE OVER 6 INCHES IN A FEW SPOTS
IF BANDS SET UP. PER COORDINATION WITH DULUTH AND MARQUETTE...WILL
HOLD OFF FOR NOW AND MIDNIGHT SHIFT MAY GO WITH AN ADVISORY.
A CLIPPER SYSTEM WILL MOVE ACROSS THE REGION SUNDAY NIGHT...BRINGING
A CHANCE OF LIGHT SNOW ACROSS THE SOUTH AND LIGHT SNOW LIKELY ACROSS
THE NORTH. AN INCH OR TWO IS EXPECTED ACROSS THE NORTH WITH LIGHTER
AMOUNTS TO THE SOUTH.
ATTENTION THEN TURNS TO WEDNESDAY THROUGH FRIDAY WITH AN UNSETTLED
PERIOD EXPECTED. PRECIPITATION SHOULD BE MAINLY RAIN ACROSS
CENTRAL AND NORTHEAST WISCONSIN...WITH MORE OF A MIX OF RAIN AND
SNOW ACROSS NORTH-CENTRAL WISCONSIN. LATEST ECMWF HAS PUSHED THE
FRONT FURTHER SOUTH ON FRIDAY WHERE THE NORTH MAY BE DRY. PLENTY
OF TIME TO WORK OUT THE DETAILS. BELOW NORMAL TEMPERATURES THIS
WEEKEND SHOULD RETURN TO OR ABOVE NORMAL BY THE MIDDLE OF NEXT
WEEK.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1025 PM CST FRI NOV 20 2015
VFR CIGS EXPECTED OVER MOST AREAS TONIGHT INTO SATURDAY.
EXCEPTIONS INCLUDE LOCALIZED MVFR CIGS WITH LIGHT SNOW MAINLY
SOUTH OF HIGHWAY 10 INCLUDING THE ATW AND MTW TAFS OVERNIGHT INTO
SATURDAY. ANOTHER EXCEPTION FOR PATCHY MVFR CIGS AND VSBYS INCLUDE
NORTH CENTRAL WISCONSIN LATE TONIGHT INTO SATURDAY NIGHT WITH
INCLUDES THE RHI TAF.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........TDH
SHORT TERM.....KALLAS
LONG TERM......ECKBERG
AVIATION.......TDH
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
1006 PM CST FRI NOV 20 2015
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 1006 PM CST FRI NOV 20 2015
LATEST TREND OF THE HRRR SUPPORTS THE 00Z NAM TO KEEP THE ACCUM
SNOW FURTHER SOUTH. WILL CANCEL THE ADVISORY.
UPDATE
ISSUED AT 915 PM CST FRI NOV 20 2015
TREND OF THE LAST FEW HOURS INDICATE A SOUTHERN SHIFT WITH THE
HEAVY SNOW BAND OVER SOUTHERN WISCONSIN. GRB SOUNDING THIS
EVENING SUGGESTS A LOT OF DRY AIR TO OVERCOME. BEST 850-700 FGEN
REGION WELL SOUTH. NORMALLY WOULD DROP THE ADVISORY WITH AMOUNTS
MINIMAL...BUT NEED TO CONSIDER THE FIRST SNOW OF THE SEASON.
THE 00Z NAM INDICATES A DIRECTION OF DROPPING THE ADVISORY...WILL
TRY TO TAKE A QUICK PEAK AT THE EARLY PART OF THE GFS THE NEXT
HOUR...AND GO FROM THERE. WE DO HAVE THE UPPER TROUGH DROPPING IN
TONIGHT INTO SATURDAY WHICH COULD PIVOT THE LIGHTER SNOW NORTH A
BIT...BUT THIS SYSTEM IS ALSO TRACKING A BIT FASTER.
&&
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 242 PM CST FRI NOV 20 2015
PRIMARY FOCUS TO BE ON THE SNOW POTENTIAL OVER SRN SECTIONS OF THE
FCST AREA LATE TNGT/SAT MORNING AS A SYSTEM PASSES BY TO OUR
SOUTH. MODEL INCONSISTENCY HAS BEEN A PROBLEM ALL WEEK...BUT IT
NOW APPEARS THAT THE 12Z RUN HAS AT LEAST TRIED TO ZERO ON A
TRACK/NRN EDGE OF SNOW. A SECONDARY FOCUS TO BE ON INCREASING LK
EFFECT FOR N-CNTRL WI AS WINDS GRADUALLY SHIFT TO THE NW AND COLD
AIR FLOWS OVER LK SUPERIOR.
THE 20Z MSAS SFC ANALYSIS SHOWED AN AREA OF HI PRES OVER THE OHIO
RIVER VALLEY WITH STRONG LOW PRES OVER HUDSON BAY AND WEAK LOW
PRES OVER THE CNTRL HI PLAINS. RADAR MOSAIC INDICATED A NARROW...
BUT INTENSE BAND OF SNOW OVER SE SD...NE NEBRASKA AND NRN IA.
SNOWFALL RATES WITHIN THIS INTENSE BAND WERE 2-3" PER HOUR!
EVEN AT THIS LATE DATE...THE NRN EDGE OF THE MAIN SNOW BAND WAS
NOT SET IN STONE AS THE MODELS CONTINUED TO TWEAK NORTH (NAM/GFS)
OR SOUTH (GEM). MODELS DO AGREE ON THE STRONG FRONTOGENETICAL
FORCING SIGNAL THAT RUNS FROM CNTRL IA E-NE INTO SRN WI/NRN IL
TNGT...THUS HIGHEST ACCUMULATION NUMBERS WL STAY TO OUR SOUTH.
HOWEVER...DO ANTICIPATE LIGHT ACCUMULATIONS (< 1") ALONG OUR SRN
TIER OF COUNTIES BY DAYBREAK. WE WL ALSO HAVE TO WATCH SFC WINDS
AS ANY SLIGHT VEERING TO THE NE COULD ADD TO ACCUMULATIONS OVER
MANITOWOC COUNTY.
LIGHT SNOW WL CONT OVER E-CNTRL WI THRU AT LEAST SAT MORNING AS
THE SFC LOW LIFTS NE FROM THE MID-MS VALLEY TOWARD THE ERN GREAT
LAKES AND MID-LEVEL FRONTOGENETICAL FORCING BEGINS TO SHIFT FROM
SE WI INTO LWR MI. AN ADDITIONAL INCH OR TWO OF ACCUMULATION IS
POSSIBLE OVER E-CNTRL WI...THUS PLAN ON ISSUING A WINTER WEATHER
ADVY FOR WINNEBAGO...CALUMET AND MANITOWOC COUNTIES FROM 03Z-21Z
SAT (PRIMARILY FOR SRN SECTIONS OF THESE COUNTIES). TRAILING THIS
SYSTEM IS A SHRTWV TROF THAT IS FCST TO SWEEP INTO THE WRN GREAT
LAKES ON SAT. WHILE THE BULK OF THE SYNOPTIC MOISTURE TO BE TIED
UP WITH THE INITIAL STORM...WINDS ARE EXPECTED TO TURN NW AND
INTRODUCE LK EFFECT SNOW SHWRS TO N-CNTRL WI. THERE IS A POTENTIAL
FOR AN INCH OR TWO OF ACCUMULATION...ESPECIALLY OVER THE SNOWBELT
REGION OF VILAS CNTY. MAX TEMPS TO ONLY BE IN THE MID TO UPR 20S
N-CNTRL...TO THE MID 30S E-CNTRL WI. ADD IN A NW WIND AT 10 TO 20
MPH AND WIND CHILL VALUES WL ONLY BE IN THE UPR TEENS TO LWR 20S.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 242 PM CST FRI NOV 20 2015
SEVERAL CONCERNS TO DEAL WITH INCLUDE LAKE EFFECT SNOW SHOWERS
ACROSS THE NORTH SATURDAY NIGHT INTO SUNDAY MORNING...A CLIPPER
SYSTEM SUNDAY NIGHT INTO MONDAY MORNING AND THEN ABOVE NORMAL
TEMPERATURES AND UNSETTLED WEATHER FOR THANKSGIVING DAY AND
BLACK FRIDAY.
PERUSAL OF THE BUFKIT SOUNDING OVER WESTERN LAKE SUPERIOR
SATURDAY NIGHT PRETTY IMPRESSIVE SATURDAY NIGHT. ABUNDANT
MOISTURE UP TO TEN THOUSAND FEET...EQL LEVELS OF TWELVE TO
FIFTEEN THOUSAND FEET AND LAKE TO 850MB TEMPERATURE DIFFERENCES
APPROACHING 20C. LOW LEVEL WINDS ARE NOT AS FAVORABLE...BUT
CLOSE ENOUGH TO WARRANT INCREASING SNOWFALL TOTALS FROM PREVIOUS
FORECAST. CONTEMPLATED LAKE EFFECT SNOW WATCH THINKING THE SNOW
BELT REGION OF VILAS COUNTY COULD SEE OVER 6 INCHES IN A FEW SPOTS
IF BANDS SET UP. PER COORDINATION WITH DULUTH AND MARQUETTE...WILL
HOLD OFF FOR NOW AND MIDNIGHT SHIFT MAY GO WITH AN ADVISORY.
A CLIPPER SYSTEM WILL MOVE ACROSS THE REGION SUNDAY NIGHT...BRINGING
A CHANCE OF LIGHT SNOW ACROSS THE SOUTH AND LIGHT SNOW LIKELY ACROSS
THE NORTH. AN INCH OR TWO IS EXPECTED ACROSS THE NORTH WITH LIGHTER
AMOUNTS TO THE SOUTH.
ATTENTION THEN TURNS TO WEDNESDAY THROUGH FRIDAY WITH AN UNSETTLED
PERIOD EXPECTED. PRECIPITATION SHOULD BE MAINLY RAIN ACROSS
CENTRAL AND NORTHEAST WISCONSIN...WITH MORE OF A MIX OF RAIN AND
SNOW ACROSS NORTH-CENTRAL WISCONSIN. LATEST ECMWF HAS PUSHED THE
FRONT FURTHER SOUTH ON FRIDAY WHERE THE NORTH MAY BE DRY. PLENTY
OF TIME TO WORK OUT THE DETAILS. BELOW NORMAL TEMPERATURES THIS
WEEKEND SHOULD RETURN TO OR ABOVE NORMAL BY THE MIDDLE OF NEXT
WEEK.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 517 PM CST FRI NOV 20 2015
VFR CIGS EXPECTED OVER MOST AREAS TONIGHT. THE ONLY EXCEPTION
WOULD BE FOR A WEST TO EAST MVFR OR LOWER END VFR CIG DEVELOPING
SOUTH OF HIGHWAY 29 TONIGHT AS A STORM SYSTEM TRACKS OVER NORTHERN
ILLINOIS. CONDITIONS WILL DETERIORATE FURTHER SOUTH OVER SOUTHERN
WISCONSIN. AS THIS SYSTEM DEPARTS SATURDAY MORNING CONDITIONS
EXPECTED TO IMPROVE. HOWEVER PATCHY MVFR CIGS OVER NORTHERN
WISCONSIN LATE TONIGHT MAY BECOME MORE WIDESPREAD ON SATURDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 3 PM CST SATURDAY FOR WIZ048>050.
&&
$$
UPDATE.........TDH
SHORT TERM.....KALLAS
LONG TERM......ECKBERG
AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1015 AM EST SAT NOV 21 2015
...INCREASED RAIN CHANCES THROUGH THIS WEEKEND FOLLOWED BY THE
COOLEST AIR OF THE DRY SEASON THUS FAR...
...HAZARDOUS BOATING CONDITIONS DEVELOPING SUNDAY AND CONTINUING
MOST OF NEXT WEEK...
.UPDATE...
CURRENT...SRLY COMPONENT TO METAR/C-MAN DATA OVER/OFFSHORE PB COUNTY
AND GRAND BAHAMA ISLAND PLACE THE DIFFUSE FRONTAL BDRY (A WARM FRONT
FOR THE TIME BEING) SOMEWHERE NORTH OF JUPITER INLET THIS MORNING.
IT`S PROBABLY OVER NORTH LAKE OKEECHOBEE...BUT BASED ON RADAR HAS
LIKELY LIFTED FARTHER NORTH OVER THE ATLC TO OFFSHORE BREVARD CO.
BDRY ALSO EXTENDS WELL WEST INTO THE GOMEX TO A WEAK LOW PRES WAVE
NEAR/ALONG 92W. WIDESPREAD MULTILAYERED CLOUDS ARE IN PLACE OVER THE
PENINSULA.
MORNING RAOBS SHOW RATHER UNIMPRESSIVE PWAT AT KXMR A LITTLE UNDER
1.5" WHILE DEEPER MEAN MOISTURE LURKS TO THE SOUTH (MFL 1.93") AND
WEST (TBW 1.76"). WATER VAPOR AND RUC MID-UPPER ANLYS FIELDS SHOW
VORTLOBES STUNG OUT ACROSS THE CENTRAL-ERN GOMEX WITH THE LEAD ONE
PUSHING INTO SE FL NEAR PGD/FMY. IMPRESSIVE SRN STREAM 80-90KT H25
JETSTREAK EXTENDS FROM THE GULF ACROSS NORTH FL WITH EXPANSIVE SWATH
OF DIVG OVHD.
REMAINDER OF TODAY...ELEMENTS LOOK TO BE IN PLACE FOR INCREASING CHC
OF RAIN OVER MUCH OF THE AREA AS INCREASING MOISTURE AND DEEP LAYER
FORCED ASCENT BEGIN TO SPREAD EAST AND OVHD THROUGH LATER TODAY.
LOCAL HRRR MODEL GUIDANCE SHOWS A GENEROUS COVERAGE A STRATIFORM
RAIN WITH EMBEDDED CONVECTION WILL DEVELOP BY LATE AFTERNOON AND
CONTINUE WELL INTO THIS EVENING. WHILE THIS MAY BE A TAD OVERDONE
MAV GUIDANCE PAINTS 50-60 POPS FOR TODAY WITH THE MET (60-80) AND
LAV (30-40) ON OPPOSITE SIDES. CURRENT GRIDS SHOW 50...WHICH SEEMS
LIKE A DECENT COMPROMISE GIVEN CURRENT RADAR AND SATELLITE TRENDS.
THINK CHC FOR THUNDER WILL BE QUITE LOW DUE TO ANTICIPATED LACK OF
INSOLATION...BUT NON-ZERO AS IT WILL BE OFFSET TO SOME DEGREE BY
COOLING ALOFT AND SLOWLY STRENGTHENING MEAN VV. ADDITIONALLY...WE
ALREADY HAD ISOLD EMBEDDED THUNDER WITH CELLS ALONG THE TREASURE
COAST AND WELL OFFSHORE BREVARD...SO EXPECT MORE OF THE SAME WITH
MODEST DAYTIME HEATING THROUGH THIS AFTERNOON.
GIVEN EXPECTED CLOUD COVER...NUDGED MAX TEMPS DOWN BY A DEGREE OR
SO...RESULTING IN ALL AREAS REACHING THE U70S TO AROUND 80F OR SO.
&&
.AVIATION...WIDESPREAD VFR OVC-BKN150 WITH LCL-AREAS MVFR BKN CIGS
IN CONVECTIVE CU...INCREASING IN COVERAGE AFT 18Z. LCL IFR VSBYS IN
+SHRA/TS...BUT GREATER COVERAGE OF MVFR VSBYS/CIGS IN PRECIP SHOULD
BECOME MORE PREVALENT.
&&
.MARINE...WARM FRONT MOVING NWD INTO THE MAOR HAS PUT A DENT IN THE
SFC PGRAD. AS A RESULT WINDS ARE 20KT OR LESS WITH SEAS 3-4FT NEAR
SHORE AND 5 TO OCNL 6FT WELL AWAY FROM THE COAST. CURRENT FORECAST
WITH SCEC 20-60NM OFFSHORE NORTH OF SEBASTIAN INLET IS SPOT ON. NO
CHGS NEEDED.
&&
UPDATE/SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT WX/DSS....BLOTTMAN
&&
.PREV DISCUSSION... /ISSUED 348 AM EST SAT NOV 21 2015/
TONIGHT...SOME OF THE DAYTIME CONVECTION MAY LINGER INTO EVENING...
BUT THE GREATEST LARGE SCALE ASCENT AHEAD OF THE SHORTWAVE WILL BE
AFTER MIDNIGHT. MOS POPS ARE VERY HIGH TONIGHT...75-90 PERCENT...
WHICH LOOKS REASONABLE GIVEN THE IMPRESSIVE DIVERGENCE ALOFT WHICH
IS DEPICTED BY THE GFS. HOWEVER THE BULK OF THIS PRECIP SHOULD BE
QUITE LATE... SO HAVE KEPT OUR PREVIOUS FORECAST FOR AREAWIDE 70
PERCENT CHANCES. WILL ALSO KEEP MENTION OF SLIGHT CHANCE FOR STORMS
OVERNIGHT DUE TO LARGE SCALE ASCENT AND WEAK ELEVATED INSTABILITY.
SUN...AN AMORPHOUS AREA OF LOW PRESSURE WILL STRETCH FROM OFF THE
SOUTHWEST COAST OF FLORIDA TOWARD THE ATLANTIC WATERS OFFSHORE
GEORGIA/SOUTH CAROLINA. THE LOW WILL ORGANIZE NORTH OF THE BAHAMAS
BEFORE ADVANCING QUICKLY TO THE NORTH AND EAST. AS IT DOES SO...A
STRONG COLD FRONT WILL ADVANCE OVER THE AREA LATE SUNDAY INTO EARLY
MONDAY.
LARGE SCALE ASCENT ALOFT WILL BE ONGOING THROUGH THE MORNING AS LOW
LEVEL CONVERGENCE IN ASSOCIATION WITH THE WEAK LOW SHIFTS TOWARDS
THE CENTRAL/SOUTHERN PENINSULA. EXPECT SHOWER COVERAGE TO BE
WIDESPREAD THROUGH AT LEAST THE FIRST HALF OF THE DAY. AS THE SYSTEM
PULLS AWAY LATE SUNDAY...RAIN CHANCES WILL LOWER AND ABATE FROM
NORTH TO SOUTH. CLOUDS WILL HOLD MAXES DOWN ON SUNDAY WHILE COLD AIR
ADVECTION BEGINS IN EARNEST SUNDAY NIGHT. EXPECTING A LARGE SPREAD
IN MINS...UPPER 40S ACROSS THE FAR NORTH AND 60-65 ALONG THE
TREASURE COAST. CONSIDERING THE VERY WARM TEMPERATURES THUS FAR THIS
FALL...AND THE FACT THAT WINDS ARE EXPECTED TO REMAIN BREEZY THROUGH
THE OVERNIGHT AND INTO EARLY MONDAY MORNING...IT WILL FEEL QUITE
CHILLY AS YOU HEAD OUT THE DOOR.
MON-FRI...COLD FRONT WILL BE WELL SOUTH OF THE AREA BY SUNRISE
MONDAY AS NORTHWEST WINDS USHER IN THE COOLEST AIR OF THE SEASON.
MAX HIGHS WILL STRUGGLE TO ESCAPE THE 60S DURING THE DAY ON MONDAY.
AS HAS BEEN THE CASE WITH NEARLY EVERY FROPA THIS SEASON...POST-
FRONTAL WINDS WILL RAPIDLY VEER ONSHORE...MODIFYING THE AIR MASS FOR
THE COASTAL COUNTIES AS EARLY AS MONDAY NIGHT. THIS WILL BE MOST
PRONOUNCED ALONG THE TREASURE COAST GIVEN THE STILL-WARM SHELF WATER
TEMPS THERE.
AS FLOW VEERS ONSHORE LATE MONDAY INTO TUESDAY...WILL LIKELY SEE
SIGNIFICANT MARINE STRATOCU FORM OVER THE ATLANTIC AND SPREAD
INLAND. BRIEF LIGHT RAIN / SPRINKLES POSSIBLE TUESDAY (CONFINED TO
THE COASTAL WATERS IN THIS FORECAST PACKAGE) BEFORE ONSHORE MOVING
SHOWERS RE-ENTER THE PICTURE MID-WEEK AND BEYOND AS MOISTURE
INCREASES IN DEEPENING EAST FLOW. MEANWHILE...TEMPS CLIMB TO NEAR
CLIMO BY WEDNESDAY AND ABOVE THU-FRI.
&&
.AVIATION...
CONDITIONS SO FAR THIS MORNING HAVE MAINLY BEEN VFR EXCEPT FOR A
FEW BRIEF MVFR CEILINGS. EXPECT THIS TREND TO CONTINUE...THEN AS
DAYTIME HEATING CLOUDS FORM...MORE AREAS OF MVFR CEILINGS SHOULD
FORM. SCATTERED SHOWERS AND A FEW STORMS ARE FORECAST DURING THE
AFTERNOON AND EARLY EVENING. A HIGHER COVERAGE OF SHOWERS AND
ISOLATED STORMS SHOULD SPREAD INLAND FROM THE GULF IN THE PRE
DAWN HOURS OF SUNDAY.
&&
.MARINE...
TODAY-TONIGHT...EAST WINDS WILL GRADUALLY VEER TO SOUTHEAST AND
EVEN SOUTH LATE IN THE DAY AS OLD FRONTAL TROUGH LIFTS BACK INTO
THE WATERS. SPEEDS LOOK TO BE 10-15 KNOTS EARLY THIS MORNING AND
EASING TO 10 KNOTS OR LESS THIS AFTERNOON. HAVE CANCELLED THE
SMALL CRAFT ADVISORY AS TIGHTENED PRESSURE GRADIENT WAS BRIEF OVER
OUR NORTHERN WATERS. EXPECT SCATTERED MAINLY AFTERNOON SHOWERS
WITH A SLIGHT CHANCE OF STORMS THROUGH EARLY EVENING. A HIGHER
COVERAGE OF SHOWERS WILL OCCUR IN THE PRE DAWN HOURS OF SUNDAY.
SUN-WED...PRESSURE GRADIENT WILL START OFF RELAXED EARLY SUNDAY
BEFORE TIGHTENING AS LOW PRESSURE ORGANIZES NORTH OF THE BAHAMAS. AS
THE LOW PULLS AWAY TO THE NORTH AND EAST...A STRONG COLD FRONT WILL
MOVE ACROSS THE COASTAL WATERS LATE SUNDAY. STRONG SUSTAINED
NORTHERLY WINDS OF AROUND 25 KNOTS WILL BUILD SEAS BEHIND THE
FRONT...RESULTING IN A QUICK TRANSITION TO HAZARDOUS BOATING/SURF
CONDITIONS THAT WILL LINGER THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. EXPECT HIGH END SCA CONDITIONS WITH GUSTS NEAR GALE
FORCE...AND SEAS AS HIGH AS 12-13FT IN THE GULF STREAM...PERHAPS
BRIEFLY HIGHER. WE ALSO MAY BE LOOKING AS DANGEROUS BEACH CONDITIONS
EARLY NEXT WEEK WITH HIGH/CHOPPY SURF AND STRONG RIPS WITH POTENTIAL
FOR ADVISORY CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 81 67 69 50 / 50 70 70 30
MCO 84 68 72 52 / 50 70 70 40
MLB 83 69 73 61 / 50 70 70 40
VRB 84 69 75 64 / 50 70 70 40
LEE 82 67 69 47 / 50 70 70 30
SFB 82 67 72 51 / 50 70 70 40
ORL 83 68 71 51 / 50 70 70 40
FPR 84 69 76 64 / 50 70 70 50
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
917 AM CST SAT NOV 21 2015
.UPDATE...
915 AM CST
ONLY CHANGE TO HEADLINES WAS TO UPGRADE ADVISORY TO A WINTER STORM
WARNING FOR LAKE AND PORTER COUNTIES IN NORTHWEST INDIANA.
MAJORITY OF FORECAST CONTINUES WELL ON TRACK...INCLUDING FOR THE
MOST PART SNOWFALL TOTALS AND ENDING TIMES TODAY.
THE WELL-DEFINED TROUGH ON SATELLITE THIS MORNING IS SWINGING
INTO THE AREA...PIVOTING SLIGHTLY MORE NEGATIVELY TILTED...WITH
RAPID MID-LEVEL AND DYNAMIC COOLING. AN IMPRESSIVE 500MB
TEMPERATURE DIFFERENCE FROM MPX TO DVN OF 16C HIGHLIGHTS THAT.
THE SURFACE TEMPERATURES ARE STARTING TO SLOWLY FALL IN NORTH
CENTRAL ILLINOIS WITH NORTHERLY WINDS. TEMPERATURES ARE ALSO
BEGINNING TO SLOWLY COOL NEAR THE IMMEDIATE LAKE SHORE OF
NORTHEAST ILLINOIS...INCLUDING DOWNTOWN CHICAGO...WHERE RAIN OR
RAIN/SNOW MIX WITH LITTLE TO NO ACCUMULATION HAS BEEN REPORTED
THUS FAR THIS MORNING. EXPECTING TO SEE THESE LOCATIONS TURN OVER
TO ALL SNOW FOR GOOD OVER THE NEXT COUPLE HOURS.
AS DEFORMATION ENVELOPS THE AREA AS NOTED IN THE PREVIOUS
DISCUSSION...WE SHOULD CONTINUE TO SEE HEAVIER SNOW BLOSSOM ON
RADAR WHICH WE HAVE NOTICED UNDULATE SINCE 7 AM. AREAS OF HALF
MILE AND TEMPORARY QUARTER MILE VISIBILITY HAVE BEEN OBSERVED
UNDER THESE. SNOWFLAKE QUALITY...OR SNOW RATIOS...ALSO APPEAR TO
INCREASE IN THESE AREAS BASED ON OUT OUR WINDOW AND A FEW OTHER
REPORTS. THAT WOULD LINE UP WITH SATURATION PROFILES...ESPECIALLY
WHERE THE WINDS ARE LIGHTER IN THE LOW-LEVELS /LESS FLAKE
FRAGMENTING/...SUCH AS NORTHEAST ILLINOIS AND FAR NORTHWEST
INDIANA AT PRESENT. TEMPORARY ONE INCH PER HOUR RATES WILL BE
MOST FAVORED IN THESE AREAS.
LAKE ENHANCEMENT CONTINUES TO BE SEEN NEAR THE WI/IL STATE
LINE...WITH EVEN SOME 40 MPH GUSTS ON THE IMMEDIATE SOUTHEAST
WISCONSIN SHORE LIKELY INDICATING THE PRESENCE OF SHARPENING
CONVERGENCE AND STEEP LAPSE RATES. THIS ENHANCEMENT WILL SLOWLY
MOVE SOUTHWARD THROUGH EARLY AFTERNOON...WITH THE LONGEST
RESIDENCE TIME JUST NORTH OF CHICAGO IT WOULD APPEAR ON THE HRRR
AND RAP PREDICTED WIND FIELDS. THIS WILL SHIFT INTO NORTHWEST
INDIANA DURING THE MID AFTERNOON OR SO AND FURTHER INCREASE RATES
AND TOTAL SNOW. WHILE SNOWFALL TOTALS IN PARTS OF LAKE AND PORTER
ARE LIKELY TO NOT REACH SIX INCHES...THE COMBINATION OF THE
HEAVIER SYNOPTIC AND EXPECTED LATER MESOSCALE RATES DURING THE
DAYTIME...AND THE FIRST EVENT OF THE YEAR...HAVE COLLABORATED THE
UPGRADE TO WARNING FOR THERE.
MTF
&&
.SHORT TERM...
330 AM CST
THROUGH MONDAY...
A VERY IMPRESSIVE DYNAMIC EARLY SEASON STORM SYSTEM HAS ONLY
PRESENTED ITS FIRST PUNCH TO PORTIONS OF THE AREA. YESTERDAY
EVENING...A VERY STRONGLY FRONTOGENTICALLY FORCED HEAVY SNOW BAND
DEVELOPED OVER FAR NORTHERN ILLINOIS AND DROPPED UP TO 10 INCHES
WITHIN A FEW HOURS. HOWEVER...AREAS FARTHER SOUTH RECEIVED LIGHTER
AMOUNTS OUT OF THIS FIRST PERIOD OF SNOW. THIS IS EXPECTED TO
CHANGE THIS MORNING...HOWEVER...AS ADDITIONAL MODERATE TO
OCCASIONALLY HEAVY BANDS OF SNOW DEVELOP OVER THE AREA AND PRESENT
THE OPPORTUNITY FOR AREAS SOUTH OF YESTERDAY EVENINGS HEAVY SNOW
EVENT TO GET SNOW ACCUMULATION.
THE TRACKS OF THE 850 AND 700 MB LOWS APPEAR QUITE FAVORABLE FOR
HEAVY SNOW ACROSS NORTHERN ILLINOIS AND NORTHWESTERN INDIANA TODAY.
STRONG Q-VECTOR CONVERGENCE IS EXPECTED TO SET UP OVER THE REGION
THIS MORNING AS THE MAIN MID LEVEL SHORT WAVE TRANSITIONS TO A
NEGATIVE TILT. THIS SUGGESTS THE PRESENCE OF STRONG LARGE SCALE
FORCING FOR ASCENT...ESPECIALLY CONSIDERING THE AREA WILL RESIDE
WITHIN THE FAVORABLE LEFT EXIT REGION OF A 120+ KT UPPER LEVEL JET.
AS THE LOWER LEVEL LOW SHIFTS EASTWARD OVER ILLINOIS...THIS WILL
RESULT IN A CORRIDOR OF RATHER STOUT DEFORMATION...AND THE RESULTANT
BANDS OF FRONTOGENESIS SHOULD DIVE AN AREA OF MODERATE...TO
OCCASIONALLY HEAVY SNOW OVER THE AREA TODAY. THIS STRONG FORCING FOR
ASCENT ALSO LOOKS TO BE COMPLEMENTED...AT LEAST OVER NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BY FAVORABLE THERMODYNAMICS FOR
LAKE ENHANCEMENT.
SURFACE TEMPERATURES HAVE REMAINED AT...OR A COUPLE OF DEGREES ABOVE
FREEZING THROUGH THE NIGHT IN MOST AREAS OUTSIDE OF NORTH CENTRAL
ILLINOIS...AND THIS HAS RESULTED IN LITTLE SNOW
ACCUMULATION...ESPECIALLY CONSIDERING SNOW RATES HAVE REMAINED
FAIRLY LIGHT OVERNIGHT. SURFACE TEMPERATURES SHOULD BEGIN TO COOL TO
AND BELOW FREEZING DURING THE DAY AS HEAVIER PRECIPITATION RATES
DEVELOP...AND THIS SHOULD ALLOW SNOW TO ACCUMULATE...ESPECIALLY ON
GRASSY AREAS. IT IS A BIT UNCERTAIN HOW MUCH SNOW WILL ACCUMULATE ON
PAVEMENT...DUE TO THE WARMER TEMPERATURES. HOWEVER...AT LEAST SOME
SLUSHY ACCUMS LOOKS POSSIBLE.
AS MENTIONED ABOVE...THERMODYNAMICS SHOULD BECOME INCREASING
FAVORABLE FOR A LAKE ENHANCED BAND OF SNOW TO DEVELOP OVER
NORTHEASTERN ILLINOIS AND EVENTUALLY NORTHWESTERN INDIANA. COOLER
MID-LEVEL TEMPERATURES MOVING OVER THE AREA SHOULD SET UP THESE
FAVORABLE CONDITIONS. HI-RES GUIDANCE IS ACTUALLY PICKING UP ON
THIS...AND SUGGESTS THAT A HEAVY LAKE ENHANCED BAND OF HEAVY SNOW
WILL IMPACT PORTIONS OF NORTHEASTERN ILLINOIS THIS MORNING.
IT APPEARS THAT THE STORM SYSTEM WILL TRACK A BIT FARTHER SOUTH THEN
WHAT WAS ANTICIPATED EARLIER. THEREFORE...IT APPEARS THAT AREAS
OUTSIDE THE CURRENT ADVISORY COULD END UP GETTING A FEW INCHES OF
ACCUMULATION TODAY. BECAUSE OF THIS...WE OPTED TO EXPAND THE WINTER
WX ADVISORY FARTHER SOUTH TO COVER THE REST OF MY AREA. OVERALL...IT
APPEARS THE HEAVIEST SNOW TODAY WILL FALL DURING THE MORNING...THEN
BEGIN TAPERING OFF FROM WEST TO EAST THROUGH THE AFTERNOON. LAKE
ENHANCED SNOW SHOWERS COULD LINGER INTO THE EVENING OVER FAR
NORTHEASTERN PORTER. OTHERWISE...THINGS SHOULD BE DONE IN MOST
AREAS BY LATER THIS AFTERNOON. IT APPEARS THAT AMOUNTS OF 3 TO 7
INCHES COULD FALL ACROSS THE AREA TODAY. THEREFORE...NO CHANGES
ARE PLANED TO THE HEADLINES...ASIDE FROM THE EXPANSION MENTIONED.
NORTH-NORTHWESTERLY WINDS WILL BECOME VERY GUSTY THIS AFTERNOON AS
THE SURFACE LOW TRACKS OVER THE EASTERN GREAT LAKES REGION. THESE
STRONGER WINDS COULD PRODUCE SOME BLOWING SNOW. HOWEVER...DUE TO THE
WETTER NATURE OF THE SNOW...THIS MAY NOT BE TOO BIG OF AN
ISSUE...AND I HAVE OPTED TO LEAVE THE MENTION OUT OF THE FORECAST AT
THIS TIME.
OTHERWISE...EXPECT A VERY COLD NIGHT TONIGHT WITH THE FRESH SNOW ON
THE GROUND. AREAS ACROSS NORTH CENTRAL ILLINOIS LOOK TO DROP INTO
THE SINGLE DIGITS...WITH TEENS LIKELY IN MOST OTHER AREAS.
SUBFREEZING TEMPERATURES WILL CONTINUE SUNDAY...BEFORE TEMPERATURES
BEGIN TO INCH ABOVE FREEZING ON MONDAY.
KJB
&&
.LONG TERM...
238 AM CST
TUESDAY THROUGH FRIDAY...
THE EXTENDED BEGINS QUIETLY WITH HIGH PRESSURE SHIFTING FROM THE
SOUTHEAST U.S. TO NEW ENGLAND BY WEDNESDAY MORNING. WINDS TURN
SOUTH WEDNESDAY USHERING IN WARMER AIR. THIS IS REFLECTED IN HIGH
TEMPS WHICH WILL JUMP FROM THE UPPER 30S TO MID 40S TUESDAY TO THE
LOW TO MID 50S THURSDAY. A WEAKENING MID LEVEL SHORTWAVE TROUGH
PASSES OVER THE REGION WEDNESDAY BRINGING A SLIGHT CHANCE TO CHANCE
OF LIGHT RAIN WITH IT. HAVE MORE CONFIDENCE IN RAIN WEDNESDAY NIGHT
THAN WEDNESDAY AS THE NEXT LOW/S WARM FRONT LIFTS NORTH OVER THE
REGION...BUT ONLY EXPECTING LIGHT RAIN. THE LOW ARRIVES OVER IOWA
THURSDAY MORNING AND CONTINUES NORTHEAST THROUGH LATE IN THE WEEK.
THE GFS IS MORE AGGRESSIVE WITH THE RAIN/S PROGRESSION THURSDAY.
THINKING AREAS WEST OF I-55 WILL LIKELY SEE RAIN WHILE THE GFS
SUGGESTS THE WHOLE WARNING AREA WILL RECEIVE RAIN. GUSTY SOUTH
WINDS ARE ALSO EXPECTED THURSDAY WITH GUSTS UP TO 30 MPH. THE LOW/S
COLD FRONT SWINGS THROUGH FRIDAY LEADING TO COOLER TEMPS...AN END TO
THE RAIN...AND NORTHWEST TO WEST WINDS. HIGH TEMPS FRIDAY WILL STILL
BE AROUND TO SLIGHTLY ABOVE AVERAGE RANGING FROM THE MID 40S TO
AROUND 50.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* PERIODS OF SNOW THROUGH THE EARLY AFTERNOON WITH VSBYS DROPPING AS
LOW AS 1/4SM DURING HEAVIEST PERIODS OF SNOW.
* IFR TO LIFR CIGS THROUGH THIS MORNING...IMPROVING TO VFR THIS
EVENING.
* EAST WINDS LESS THAN 10 KT BECOME NE AND INCREASE TO ARND 10 KT
LATE THIS MORNING. WINDS THEN BACK TO NNW AND GUST TO 20-25KT
THIS AFTN.
JEE/MM
//DISCUSSION...UPDATED 12Z...
SNOW WILL INCREASE THIS MORNING WITH 3/4 SM VSBY EXPECTED AT ALL
OF THE TAF SITES. PERIODS OF 1/4 SM VSBY ARE NOT OUT OF THE
QUESTION ACROSS THE EASTERN TERMINALS. A LAKE EFFECT BAND WILL
FORM LATE THIS MORNING AND ROTATE OVER THE EASTERN TERMINALS.
1/4SM WITH HEAVY SNOW IS EXPECTED UNDER THIS BAND ALONG WITH QUICK
ACCUMULATIONS. HOWEVER THE BAND WILL BE TRANSIENT SO THE HEAVY
SNOW WILL LAST ABOUT AN HOUR OR LESS. RFD WILL NOT BE AFFECTED BY
THE BAND AND WILL SEE THE SNOW END FIRST AROUND NOON. EAST WINDS
WILL BE LESS THAN 10 KT EARLY THIS MORNING AND INCREASE TO CLOSE
TO 10 KT LATE THIS MORNING. WINDS WILL BE BACKING LATE THIS
MORNING AND BECOME NORTHWEST GUSTING TO 20-25 KT EARLY THIS AFTN.
FLURRIES OR LIGHT SNOW MAY PERSIST PAST 19Z AT THE EASTERN
TERMINALS...BUT NOT EXPECTING ANY SIGNIFICANT IMPACT FROM THE
LINGERING SNOW.
LIFR CIGS WILL LIFT AFTER THE SNOW TO MVFR AND CLEAR OUT THIS
EVENING WITH WINDS BECOMING SOUTHWEST SUNDAY MORNING.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN SNOW THROUGH THE MORNING WITH PERIODS OF LIFR
VSBY UNDER HEAVIEST SNOW BANDS.
* MEDIUM-HIGH CONFIDENCE IN OCCURRENCE AND TIMING OF A LAKE EFFECT
BAND WITH 1/4SM VSBY.
* HIGH CONFIDENCE IN CIG AND WIND TRENDS.
JEE/MM
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR. SOUTHWEST WINDS.
MONDAY...VFR. WEST WINDS.
TUESDAY...VFR. SOUTH WINDS.
WEDNESDAY...SCHC-CHC -RA. SOUTH WINDS.
THURSDAY...RA LIKELY. MVFR PSBL. GUSTY SOUTH WINDS BECOMING WEST.
FRIDAY...CHC RAIN. IMPROVING TO VFR. NORTHWEST WINDS.
JEE
&&
.MARINE...
238 AM CST
NO CHANGES TO CURRENT SMALL CRAFT ADVISORY AND GALE WARNING. WILL
LIKELY NEED ANOTHER GALE HEADLINE FOR THE SOUTHERN HALF OF THE LAKE
SUNDAY EVENING AND NIGHT...BUT WILL HOLD OFF ON ISSUING ONE NOW
GIVEN THE CURRENT HEADLINES.
WINDS WILL BECOME NORTH TO NORTHWEST ACROSS THE LAKE THIS AFTERNOON
AS THE LOW PRESSURE SYSTEM CURRENTLY OVER TEXAS MOVES OVER THE OHIO
RIVER VALLEY. NW WINDS WILL INCREASE TO GALE FORCE ACROSS THE
SOUTHERN HALF OF THE LAKE AND INDIANA NEARSHORE ZONES. WINDS
DIMINISH OVERNIGHT AS THE LOW MOVES OVER QUEBEC. HIGH PRESSURE
SPREADS OVER THE SOUTHERN MISSISSIPPI VALLEY AND SOUTHEAST U.S. AS
ANOTHER LOW SHIFTS SOUTHEAST OVER ONTARIO SUNDAY NIGHT INTO MONDAY.
WINDS BACK TO SOUTHWEST AND GALES ARE EXPECTED SUNDAY NIGHT ACROSS
THE SOUTHERN HALF OF THE LAKE. WINDS DIMINISH AND BECOME WEST BEHIND
THE LOWS COLD FRONT MONDAY. WINDS BACK TO SOUTH AHEAD OF THE NEXT
LOW TUESDAY AND INCREASE TO 15-25 KT WEDNESDAY. THE LOW IS PROGGED
TO PASS JUST NORTHWEST AND NORTH OF THE LAKE THURSDAY NIGHT INTO
FRIDAY WITH SOUTH WINDS INCREASING TO AT LEAST 30 KT THURSDAY
BECOMING WEST 20-25 KT BEHIND THE LOW. SOME GUIDANCE MEMBERS DO
SUGGEST WE COULD HAVE GALES THURSDAY.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ022 UNTIL 3 PM
SATURDAY.
WINTER WEATHER ADVISORY...ILZ021-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 3 PM SATURDAY.
IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 6 PM SATURDAY.
WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 6 PM
SATURDAY.
LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 9 AM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745-LMZ777-LMZ779...3 PM
SATURDAY TO 3 AM SUNDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 3 PM SATURDAY.
&&
$$
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
608 AM CST SAT NOV 21 2015
.SHORT TERM...(Today)
ISSUED AT 336 AM CST SAT NOV 21 2015
the 09z/3am surface analysis shows the center of the low pressure in
south-central Missouri, with a warm front extending across southern
IL, roughly along I-70. The rain-snow line has maintained farther
north...with snow remaining north of a line from Macomb to Peoria to
Pontiac. The Peoria airport just SW of Peoria has little to no snow,
while the north side of Peoria has what looks to be at least an inch
of snow, and possibly more, on grassy surfaces based on IDOT
cameras. Reports of 2.5" of snow have come in from Knox county
observers in Altona and Abingdon earlier tonight.
The RAP and HRRR take the surface low across southern IL, with
deformation band snows continuing in our NW counties. Cold air along
the northern edge of the system will gradually get pulled southward
into our counties, prompting the rain to change to snow
progressively farther south and east. Snowfall amounts look on track
for our NW counties to be in the 3 to 6 inch range, with a sharp
cutoff down to an inch or less. As the deformation band progresses
across central IL into the afternoon, our NE counties could see
snowfall amounts up to an inch or possibly a little more toward
Hoopeston. We did not expand the winter weather advisory eastward, as
snow amounts should remain enough below the 3" criteria for
Champaign and Vermilion counties. The southern row of counties of
our advisory (Fulton, Tazewell, McLean) will be borderline in terms
of snow amounts as well, but will continue with headlines unchanged
as there remains some uncertainty as to how soon the cold air will
surge southward to change rain to snow, and how efficient of
snowfall production will occur in our NW areas.
Temps will remain warm enough for rain south of I-72 for a majority
of the day, with any change to snow coming so late in the event
that little to no snow accumulation is expected south of there.
The center of the surface low is forecast to pull into Indiana by 11
am/17z, so cold air will invade on strong NW winds by early
afternoon. High temps will likely occur by Noon in most areas
because of that, with steady or falling temps this afternoon as
winds increase to 25-30 mph. The snow should generally be too wet to
blow around, but wind chills could drop into the teens in our W-NW
counties.
.LONG TERM...(Tonight through Friday)
ISSUED AT 336 AM CST SAT NOV 21 2015
Strong short wave to lift ne of central IL early this evening with
Canadian high pressure over the central Rockies quickly ridging east
into the mid MS river valley by dawn Sunday. Clouds to decrease from
west to east later this afternoon and into the evening while nw
winds 15-25 mph at sunset today diminish to 5-10 mph overnight.
Diminishing clouds and winds to bring a very cold night to the
area especially over northern CWA where snow cover where lows will
be 7- 13F with mid teens over central parts of CWA and upper teens
to near 20F in southeast IL. Wind chills will lower to 5 above to
5 below zero northern cwa and 10-15 southeast IL. This will be the
coldest night since March 6th over central IL. High pressure
ridges into the Ohio river valley by sunset Sunday while upper
level trof axis shifts east of IL. A mostly sunny but cold day
with highs ranging form lower 30s from i-74 ne, mid 30s central
CWA and upper 30s sw CWA. Winds to become ssw at 7-14 mph by
Sunday afternoon.
After a taste of winter weather this weekend for IL, temperatures to
moderate back above normal during the upcoming work week with upper
level heights rising over the region and nearly zonal upper level
flow Monday becoming sw by mid week with strong upper level ridge in
the east and strong upper level low/trof digging in the western
states. Dry weather expected Monday through Wednesday with temps
warming back up. Lows Sunday night in the mid to upper 20s. Highs
Monday range from lower 40s from I-74 ne where remaining snow cover
likely to melt while upper 40s to near 50F sw CWA. Highs by Wed in
the low to mid 50s and mid to upper 50s on Thanksgiving day. 00Z
models have trended slower with qpf returning to IL Wed night and
Thu and looks like a wet period from Wed night into early Sat. GFS
is quicker than ECMWF model with cold front moving through later Thu
night and Friday with highest pops will likely be. Between 1 and 2
inches of rain appear possible during this time frame. Rain chances
diminish next weekend and colder air returns to central/se IL.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 600 AM CST SAT NOV 21 2015
Conditions are expected to continue at IFR or LIFR for PIA and BMI
where snow will fall through the morning and into early afternoon.
IFR conditions will develop at SPI, DEC and CMI as the morning
progresses, as rain changes to snow. Low pressure will pass south
of the area this morning, roughly just south of I-70. The low will
move into Indiana before Noon/18z, causing winds to shift to the
NE, then N, then NW by afternoon for all TAF sites. Wind speeds
will increase to 15 to 20kt after 15z, with gusts to 30kt at times
this afternoon. Winds will diminish to 8-12kt after 00z.
Initially, surface temps will hover right around or just above
freezing early this morning for a few hours. Ground temperatures
are generally above freezing, so snow accumulation on travel
surfaces will remain lower than grassy areas. 1 inch of slushy
accumulation could occur at PIA, with less than an inch at BMI and
CMI, and little to no snow accumulation at DEC and SPI. IFR
conditions should gradually improve to MVFR during the afternoon
and then to VFR after 00-03z.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until noon CST today for ILZ027>031-
036>038.
&&
$$
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS GOODLAND KS
506 AM MST SAT NOV 21 2015
.UPDATE...
ISSUED AT 456 AM MST SAT NOV 21 2015
SMALL AREA OF FLURRIES MOVING THROUGH THE SOUTHWEST QUADRANT OF
THE AREA AT THIS TIME. HRRR DOES CATCH THIS SMALL AREA. SO ADDED
SCATTERED FLURRIES TO THE ABOVE MENTIONED AREA FOR THE NEXT FEW
HOURS. ALSO INCREASED SKY COVER TO CATCH CURRENT SATELLITE AND
SURFACE OBSERVATION TRENDS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 210 AM MST SAT NOV 21 2015
MAIN FORECAST PROBLEM WILL BE TEMPERATURES. SATELLITE SHOWING A
SOMEWHAT AMPLIFIED BUT STILL PROGRESSIVE FLOW FROM THE PACIFIC INTO
THE WESTERN ATLANTIC.
AT JET LEVEL...THE ECMWF STARTED OUT BETTER THAN THE REMAINING
OUTPUT. AT MID LEVELS...ALL MODELS STARTED OUT WELL WITH MAYBE THE
GFS/CANADIAN/UKMET HAVING AN EVER SO SLIGHT ADVANTAGE. THE ECMWF WAS
DOING A LITTLE BETTER ON THE SURFACE WIND AND PRESSURE FIELD. THE
ECMWF WAS DOING A LITTLE BETTER THAN THE GFS/CANADIAN ON THE LOW
LEVEL THERMAL FIELD.
TODAY/TONIGHT...AREA REMAINS IN SUBSIDENCE FROM UPPER JET AS MID
LEVEL RIDGE BUILDS IN. COLD AND DRY AIR POURING INTO THE AREA.
SATELLITE STILL SHOWING A NARROW BUT SUBSTANTIAL SNOWFIELD FROM THE
SOUTHWEST CORNER TO NEAR THE NORTHEAST CORNER. BIG DIFFERENCES IN
TEMPERATURES BETWEEN WHERE THERE IS NO SNOW AND THIS SNOW FIELD.
SIGNIFICANT CLEARING SHOULD OCCUR. CONSIDERING THE CHANGE IN AIR
MASS AND YESTERDAYS TEMPERATURES...MADE ONLY SLIGHT ADJUSTMENTS TO
THE TEMPERATURES WITH THE COOLEST IN THE SNOWFIELD. LIGHT WESTERLY
WINDS TONIGHT. SO WOULD EXPECT THE SNOWFIELD AND LOCATIONS JUST
DOWNSTREAM OF THE SNOWFIELD TO BE THE COLDEST.
SUNDAY/SUNDAY NIGHT...SUBSIDENCE AND RIDGING CONTINUE/STRENGTHENS
ACROSS THE AREA. AIR MASS WARMS AND DO HAVE DOWNSLOPE WINDS OVER THE
ENTIRE AREA. HOWEVER THOSE WINDS LOOK TO BE BLOWING ALONG THE LENGTH
OF THAT SNOWFIELD. NOT SURE HOW MUCH THE AIR MASS WILL BE
MODIFIED...ESPECIALLY IN THE SNOWFIELD. TENDED TO WARM TEMPERATURES
FROM THE PREVIOUS FORECAST IN LOCATIONS THAT WILL NOT BE AFFECTED BY
THE SNOWFIELD. MADE LITTLE TO NO ADJUSTMENTS FOR THE SNOWFIELD
AFFECTED AREAS.
WINDS LOOK TO BE A LITTLE STRONGER DURING THE NIGHT WITH MORE WARM
AIR ADVECTION OCCURRING. SO TEMPERATURES WARMER AND MORE UNIFORM.
MONDAY/MONDAY NIGHT...WEAK RIDGING/ZONAL FLOW ALOFT IS OVER THE
REGION. MODELS ARE IN DISAGREEMENT IN WHAT TO DO WITH THE WIND
FIELD. IT IS ALMOST LIKE SOME OF THE MODELS PUSH A WEAK BOUNDARY
INTO THE AREA. OVERALL THE WIND FIELD LOOKS LIGHT WHICH IS NOT
CONDUCIVE TO A BIG WARMUP. THIS COMBINED WITH THE SNOWFIELD MAKES
THE TEMPERATURES A LITTLE MORE DIFFICULT. AGAIN ONLY MADE SLIGHT
ADJUSTMENTS TO THE HIGH TEMPERATURES.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 145 AM MST SAT NOV 21 2015
TUESDAY-WEDNESDAY...CLOSED UPPER LOW DEEPENING OVER THE WESTERN US
RESULTS IN DEEP SW FLOW ACROSS OUR CWA AND GOOD WAA. DEEP DRY AIR
MASS WILL PREVENT ANY SHOWER/THUNDERSTORM DEVELOPMENT DESPITE
INCREASING INSTABILITY AND WEAK SHORTWAVE TROUGHS EMBEDDED WITHIN SW
FLOW. CURRENTLY EXPECTED THESE PERIOD TO REMAIN DRY WITH ABOVE
NORMAL TEMPERATURES BOTH DAYS. I CONTINUED TO ACCOUNT FOR SNOW
FIELD...THOUGH ITS IMPACT SHOULD CONTINUE TO DECREASE AS FURTHER
MELTING OCCURS SUNDAY/MONDAY.
WEDNESDAY NIGHT-THURSDAY...MESSY AND COLD WEATHER PATTERN POSSIBLE
FOR THANKSGIVING AS UPPER LOW BEGINS TO SHIFT EASTWARD AND ARCTIC
FRONT DROPS SOUTH ACROSS THE PLAINS. EXPERIENCE WITH SIMILAR EVENTS
LEADS ME TO FAVOR FASTER FRONTAL TIMING AND COLDER
TEMPERATURES...AND I TRENDED THIS WAY. WITH EXTENSIVE CLOUD
COVER/POSSIBLE PRECIPITATION WE MAY NOT SEE HIGHS OUT OF THE TEENS.
IT IS STILL FAR ENOUGH OUT THAT I ONLY MADE INCREMENTAL ADJUSTMENTS
DOWNWARD ON TEMPERATURES FROM CONSENSUS BLEND. MODELS ARE SHOWING
BEST PRECIP SIGNAL WED NIGHT THROUGH THURSDAY.
TEMPERATURE/MOISTURE PROFILES WED NIGHT AND THURSDAY FAVOR A MIX
OF FREEZING RAIN (MAYBE A SHORT PERIOD OF SLEET) WITH SATURATED
LAYER ABOUT 3-5KFT DEEP 0C TO -8C UNTIL AROUND SUNSET THURSDAY.
AS I MENTIONED...I COULD SEE BL TEMPS COOLER THAN PROJECTED AND
THIS MIGHT FAVOR A TRANSITION TO MAINLY SNOW EARLIER ACROSS THE
NORTH/NORTHWEST. I KEPT MENTION OF FREEZING DRIZZLE/SNOW WHERE
DEEPER COLD LAYER IS MOST LIKELY WITH RAIN/FREEZING RAIN IN OUR
SOUTH/SOUTHEAST. AT THIS TIME IT APPEARS ANY ACCUMULATIONS SHOULD
BE LIGHT IF WE DO SEE ICE OR SNOW. CONDITIONS WILL BE SLICK AND
COLD EITHER WAY THOUGH...SO WE WILL NEED TO CONTINUE MONITORING
THIS AS WE MAY END UP NEEDING SOME FLAVOR OF ADVISORY.
FRIDAY...EVOLUTION OF UPPER LOW AND EROSION OF SHALLOW COLD AIR
MASS IS LESS CERTAIN DURING THESE PERIODS AND MODELS ARE SHOWING
MUCH MORE VARIANCE IN HEIGHT PATTERNS AND A LESS CONSISTENT PRECIP
SIGNAL. THERE IS SIGNIFICANT ENSEMBLE SPREAD WITH GEFS.
DETERMINISTIC GUIDANCE ISNT ANY BETTER WITH ECMWF SHOWING CLOSED
LOW REMAINING WEST AND LARGE SCALE TROUGH ELONGATING ACROSS THE
PLAINS...WHILE GFS/GEM BOTH BREAK DOWN CLOSED CENTER AND PROGRESS
THIS UPPER LOW QUICKLY ACROSS THE PLAINS. EITHER SOLUTION WILL
FAVOR COLD TEMPERATURES FRIDAY...HOWEVER THESE VARIANCES DO LEAD
TO LESS CONFIDENCE IN PRECIP CHANCES BEYOND THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 456 AM MST SAT NOV 21 2015
FOR KGLD...FLURRIES WITH MVFR CEILINGS WILL OCCUR THROUGH THE
FIRST COUPLE HOURS OF THE FORECAST. AFTER THAT...VFR CONDITIONS
ARE EXPECTED THROUGH THE PERIOD. NORTHWEST WINDS AT 5 TO AROUND 10
KNOTS WILL GRADUALLY SHIFT TO THE WEST AND SOUTHWEST THROUGH THE
PERIOD.
FOR KMCK...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD.
NORTHWEST WINDS OF 5 TO NEAR 10 KNOTS WILL GRADUALLY SHIFT TO THE
WEST AND SOUTHWEST THROUGH THE PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...BULLER
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS CARIBOU ME
920 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE REGION TODAY. LOW PRESSURE WILL
MOVE NORTHWEST OF THE AREA ON SUNDAY WITH SOME RAIN. A SECOND
AREA OF LOW PRESSURE WILL LIFT ACROSS THE GULF OF MAINE SUNDAY
NIGHT AND THEN INTO THE MARITIMES ON MONDAY WITH MUCH COLDER AIR.
&&
.NEAR TERM /THROUGH TONIGHT/...
920 AM UPDATE...
CRYSTAL CLR SKIES ACRS NRN AND SERN ZONES THIS MRNG WITH HIGH CLDS
STREAMING NORTH INTO CNTRL SXNS AHD OF S/WV MOVING UP ON SW FLOW.
HV GONE WITH MOSUNNY SKIES THIS MRNG FOR NRN SXNS FOR A FEW MORE
HRS BUT EXPECT MID-HIGH CLDS TO WORK IN BY LATE MRNG. ADJUSTED
GRIDS FOR HRLY T/TD VALUES BUT TEMPS SHUD QUICKLY WARM THIS MRNG.
MAY NEED TO BOOST HIGHS A DEGREE OR TWO WITH NEXT UPDATE. NO OTHER
CHGS NEEDED AT THIS TIME AS HIPRES WL BUILD EAST INTO AREA THIS
AFTN.
PREV DISCUSSION BLO...
HIGH PRESSURE WILL BUILD IN FROM THE WEST THIS MORNING WITH
CLEARING EARLY TODAY. THE HIGH PRESSURE SYSTEM WILL CREST OVER THE
REGION TODAY THEN MOVE OFF TO THE EAST THIS EVENING. WEAK LOW
PRESSURE WILL DEVELOP OVER THE GULF OF MAINE BEHIND THE DEPARTING
LOW AND SPREAD RAIN AND SNOW INTO NEW BRUNSWICK TONIGHT. INTENSE
LOW PRESSURE WILL MOVE INTO THE GREAT LAKES TONIGHT THEN MOVE INTO
SOUTHEASTERN QUEBEC PROVINCE EARLY SUNDAY.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
AN INTERESTING SETUP FOR SUNDAY NIGHT INTO EARLY MONDAY.
A FRONTAL SYSTEM IS FORECAST TO SLIDE ACROSS THE AREA ON SUNDAY
W/SOME SHOWERS OR LIGHT RAIN PULLING OUT OF THE AREA IN THE
MORNING. THE 2ND BATCH OF PRECIP IN THE FORM OF RAIN IS EXPECTED
TO SET UP LATER IN DAY AS LOW PRES DEVELOPS OFF THE SOUTHERN NEW
ENGLAND COAST AND LIFTS NNE. THE AREAS THAT WILL SEE MEASURABLE
QPF WILL BE ACROSS THE EASTERN 1/2 OF THE CWA WHERE THE BEST
FORCING AND LLVL CONVERGENCE WILL BE LOCATED. AS THE LOW LIFTS TO
NNE AND THE UPPER TROF DIGS SOME AS IT SWINGS INTO THE NE, COLDER
AIR WILL START TO FILTER INTO THE REGION. THE ECMWF AND GFS ARE IN
AGREEMENT W/THE COLDER AIR COMING IN BY THE EVENING WHILE THE
CANADIAN GEM & NAM HOLD THE COLDER AIR BACK BY 3-6 HRS. DECIDED TO
GO W/A CONSENSUS BLEND OF THE GUIDANCE FOR THIS PACKAGE SHOWING
RAIN GOING OVER TO A PERIOD OF SNOW BY 11 PM OR SO. ALL THE
GUIDANCE IS IN AGREEMENT THAT THE BULK OF THE QPF WILL BE ACROSS
THE EASTERN 3RD OF THE CWA SAY FROM FROM HOULTON DOWN INTO HANCOCK
AND WASHINGTON COUNTY W/UP AROUND 0.50 INCHES. ATTM, IF THERE IS
TO BE ANY SNOWFALL ACCUMULATION, IT WILL BE ACROSS EASTERN
WASHINGTON COUNTY W/A SLUSHY INCH POSSIBLE BEFORE THINGS WIND DOWN
MONDAY MORNING. TEMPERATURES ARE FORECAST TO DROP DOWN INTO THE
LOWER 30S ACROSS EASTERN AREAS AFTER MIDNIGHT W/MID AND UPPER 20S
BACK ACROSS THE W AND NW AREAS.
THE LOW IS FORECAST TO QUICKLY LIFT ACROSS THE MARITIMES ON MONDAY
W/CAA POURING INTO THE REGION AND DRIER CONDITIONS. THERE IS SOME
CONCERN THE CLOUDS ACROSS NORTHERN AND EASTERN MAINE MIGHT HANG ON
THROUGH MONDAY W/A NNW FLOW COMING IN OFF THE OPEN ST. LAWRENCE.
THE GFS SOUNDINGS HINT AT THIS TO BE POSSIBLE W/SOME MOISTURE
SHOWING UP BELOW 3000 FT. THIS SETUP SIMILAR TO THIS SCENARIO TOOK
PLACE LAST WEEK WHEN A CLOUD DECK BELOW 2500 FT HUNG ON LONGER
THAN ANTICIPATED. TEMPERATURES ON MONDAY WILL BE HELD DOWN INTO
THE 30S W/CLOUDS AND A NNW WIND OF 10 TO 20 MPH.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A NNW WIND AND CLOUDS LOOK TO HANG ON ESPECIALLY FOR NORTHERN AND
EASTERN AREAS MONDAY NIGHT W/CAA CONTINUING TO POUR INTO THE
REGION. ANOTHER ITEM TO BE AWARE OF WILL BE POTENTIAL FOR STREAMERS
OF LIGHT SNOW FROM THE OPEN ST. LAWRENCE FOR PORTIONS OF NORTHERN
AND EASTERN MAINE. THE MODEL GUIDANCE TENDS TO HAVE A DIFFICULT
TIME IN PICKING UP THIS MESO-SCALE FEATURE. THE HRRR MODEL AND
NAM12 TEND TO CATCH ON AS WE CLOSE IN CLOSER TO THE EVENT.
CONTINUED BREEZY AND COLD ON TUESDAY W/SOME PARTIAL CLEARING
ACROSS NORTHERN MAINE AS HIGH PRES STARTS TO MOVE IN FROM THE W.
DOWNEAST AND THE COAST SHOULD SEE A DECENT AMOUNT OF SUNSHINE.
DAYTIME TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL FOR LATE
NOVEMBER.
STRONG HIGH PRES IS FORECAST TO BUILD ACROSS THE REGION TUESDAY
NIGHT INTO WEDNESDAY AND THEN LIFT TO THE NE INTO THE NW ATLC ON
THANKSGIVING DAY. THIS WILL MEAN DRY TRAVEL WEATHER FOR THE
THANKSGIVING HOLIDAY W/MODERATING TEMPERATURES.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: EXPECT VFR CONDITIONS TODAY AND TONIGHT.
SHORT TERM: IFR/MVFR CONDITIONS FOR SUNDAY W/IFR MAINLY FROM KHUL
TO KBHB. MVFR FOR THE REMAINDER OF THE TAF SITES THROUGH SUNDAY
EVENING. CONDITIONS EXPECTED TO IMPROVE TO VFR FOR KBGR AND KBHB
FRO MONDAY WHILE THE NORTHERN TAF SITES COULD SEE PERIODS OF MVFR
CIGS. ATTM, VFR EXPECTED FOR ALL TAF SITES FOR TUESDAY INTO
WEDNESDAY
&&
.MARINE...
UPDATE 0615 AM: HAVE REMOVE SCA FOR ZONES 51 & 52 AND WILL KEEP
SCA FOR ZONE 50 UNTIL 15Z.
NEAR TERM: FOR SUSTAINED WINDS HAVE USED THE NAM12. FOR WAVES:
BUOY OBSERVATIONS INDICATE LONG PERIOD INCOMING SWELL STILL
PRESENT FROM SOUTHEASTERLY FETCH EARLY FRIDAY. EXPECT THIS TO
SUBSIDE RAPIDLY EARLY TODAY WITH OFF-SHORE WIND WAVE BECOMING THE
PREDOMINATE WAVE SYSTEM. SEAS WILL SUBSIDE RAPIDLY TONIGHT ALONG
WITH WINDS WITH LONG PERIOD SOUTHEASTERLY WAVE SYSTEM 1-2 FEET/8
SECONDS ONCE AGAIN BECOMING PREDOMINATE.
SHORT TERM: LOOKING FOR THE POTENTIAL FOR SCA CONDITIONS TO
DEVELOP SUNDAY NIGHT INTO MONDAY ESPECIALLY FOR THE OUTER ZONES.
WINDS ARE EXPECTED TO INCREASE TO 15 TO 20 KT W/GUSTS OF 25 KTS
AND A SWELL GENERATION TAKING PLACE ALLOWING FOR SEAS TO BUILD TO
5 TO 7 FT. AS A MATTER OF FACT, SCA CONDITIONS COULD HANG ON RIGHT
INTO MONDAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE LOW PASSING
ACROSS THE MARITIMES AND STRONG HIGH PRES MOVING IN FROM THE W.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR ANZ050.
&&
$$
NEAR TERM...FARRAR/MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...FARRAR/MIGNONE/HEWITT
MARINE...FARRAR/MIGNONE/HEWITT
AREA FORECAST DISCUSSION
NWS CARIBOU ME
623 AM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE REGION TODAY. LOW PRESSURE WILL
MOVE NORTHWEST OF THE AREA ON SUNDAY WITH SOME RAIN. A SECOND
AREA OF LOW PRESSURE WILL LIFT ACROSS THE GULF OF MAINE SUNDAY
NIGHT AND THEN INTO THE MARITIMES ON MONDAY WITH MUCH COLDER AIR.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE 6:15 AM: HAVE ADJUSTED TEMPERATURE AND DEW POINT BASED ON
LATEST OBSERVATIONS. NO OTHER CHANGES.
HIGH PRESSURE WILL BUILD IN FROM THE WEST THIS MORNING WITH
CLEARING EARLY TODAY. THE HIGH PRESSURE SYSTEM WILL CREST OVER THE
REGION TODAY THEN MOVE OFF TO THE EAST THIS EVENING. WEAK LOW
PRESSURE WILL DEVELOP OVER THE GULF OF MAINE BEHIND THE DEPARTING
LOW AND SPREAD RAIN AND SNOW INTO NEW BRUNSWICK TONIGHT. INTENSE
LOW PRESSURE WILL MOVE INTO THE GREAT LAKES TONIGHT THEN MOVE INTO
SOUTHEASTERN QUEBEC PROVINCE EARLY SUNDAY.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
AN INTERESTING SETUP FOR SUNDAY NIGHT INTO EARLY MONDAY.
A FRONTAL SYSTEM IS FORECAST TO SLIDE ACROSS THE AREA ON SUNDAY
W/SOME SHOWERS OR LIGHT RAIN PULLING OUT OF THE AREA IN THE
MORNING. THE 2ND BATCH OF PRECIP IN THE FORM OF RAIN IS EXPECTED
TO SET UP LATER IN DAY AS LOW PRES DEVELOPS OFF THE SOUTHERN NEW
ENGLAND COAST AND LIFTS NNE. THE AREAS THAT WILL SEE MEASURABLE
QPF WILL BE ACROSS THE EASTERN 1/2 OF THE CWA WHERE THE BEST
FORCING AND LLVL CONVERGENCE WILL BE LOCATED. AS THE LOW LIFTS TO
NNE AND THE UPPER TROF DIGS SOME AS IT SWINGS INTO THE NE, COLDER
AIR WILL START TO FILTER INTO THE REGION. THE ECMWF AND GFS ARE IN
AGREEMENT W/THE COLDER AIR COMING IN BY THE EVENING WHILE THE
CANADIAN GEM & NAM HOLD THE COLDER AIR BACK BY 3-6 HRS. DECIDED TO
GO W/A CONSENSUS BLEND OF THE GUIDANCE FOR THIS PACKAGE SHOWING
RAIN GOING OVER TO A PERIOD OF SNOW BY 11 PM OR SO. ALL THE
GUIDANCE IS IN AGREEMENT THAT THE BULK OF THE QPF WILL BE ACROSS
THE EASTERN 3RD OF THE CWA SAY FROM FROM HOULTON DOWN INTO HANCOCK
AND WASHINGTON COUNTY W/UP AROUND 0.50 INCHES. ATTM, IF THERE IS
TO BE ANY SNOWFALL ACCUMULATION, IT WILL BE ACROSS EASTERN
WASHINGTON COUNTY W/A SLUSHY INCH POSSIBLE BEFORE THINGS WIND DOWN
MONDAY MORNING. TEMPERATURES ARE FORECAST TO DROP DOWN INTO THE
LOWER 30S ACROSS EASTERN AREAS AFTER MIDNIGHT W/MID AND UPPER 20S
BACK ACROSS THE W AND NW AREAS.
THE LOW IS FORECAST TO QUICKLY LIFT ACROSS THE MARITIMES ON MONDAY
W/CAA POURING INTO THE REGION AND DRIER CONDITIONS. THERE IS SOME
CONCERN THE CLOUDS ACROSS NORTHERN AND EASTERN MAINE MIGHT HANG ON
THROUGH MONDAY W/A NNW FLOW COMING IN OFF THE OPEN ST. LAWRENCE.
THE GFS SOUNDINGS HINT AT THIS TO BE POSSIBLE W/SOME MOISTURE
SHOWING UP BELOW 3000 FT. THIS SETUP SIMILAR TO THIS SCENARIO TOOK
PLACE LAST WEEK WHEN A CLOUD DECK BELOW 2500 FT HUNG ON LONGER
THAN ANTICIPATED. TEMPERATURES ON MONDAY WILL BE HELD DOWN INTO
THE 30S W/CLOUDS AND A NNW WIND OF 10 TO 20 MPH.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A NNW WIND AND CLOUDS LOOK TO HANG ON ESPECIALLY FOR NORTHERN AND
EASTERN AREAS MONDAY NIGHT W/CAA CONTINUING TO POUR INTO THE
REGION. ANOTHER ITEM TO BE AWARE OF WILL BE POTENTIAL FOR STREAMERS
OF LIGHT SNOW FROM THE OPEN ST. LAWRENCE FOR PORTIONS OF NORTHERN
AND EASTERN MAINE. THE MODEL GUIDANCE TENDS TO HAVE A DIFFICULT
TIME IN PICKING UP THIS MESO-SCALE FEATURE. THE HRRR MODEL AND
NAM12 TEND TO CATCH ON AS WE CLOSE IN CLOSER TO THE EVENT.
CONTINUED BREEZY AND COLD ON TUESDAY W/SOME PARTIAL CLEARING
ACROSS NORTHERN MAINE AS HIGH PRES STARTS TO MOVE IN FROM THE W.
DOWNEAST AND THE COAST SHOULD SEE A DECENT AMOUNT OF SUNSHINE.
DAYTIME TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL FOR LATE
NOVEMBER.
STRONG HIGH PRES IS FORECAST TO BUILD ACROSS THE REGION TUESDAY
NIGHT INTO WEDNESDAY AND THEN LIFT TO THE NE INTO THE NW ATLC ON
THANKSGIVING DAY. THIS WILL MEAN DRY TRAVEL WEATHER FOR THE
THANKSGIVING HOLIDAY W/MODERATING TEMPERATURES.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: EXPECT VFR CONDITIONS TODAY AND TONIGHT.
SHORT TERM: IFR/MVFR CONDITIONS FOR SUNDAY W/IFR MAINLY FROM KHUL
TO KBHB. MVFR FOR THE REMAINDER OF THE TAF SITES THROUGH SUNDAY
EVENING. CONDITIONS EXPECTED TO IMPROVE TO VFR FOR KBGR AND KBHB
FRO MONDAY WHILE THE NORTHERN TAF SITES COULD SEE PERIODS OF MVFR
CIGS. ATTM, VFR EXPECTED FOR ALL TAF SITES FOR TUESDAY INTO
WEDNESDAY
&&
.MARINE...
UPDATE 0615 AM: HAVE REMOVE SCA FOR ZONES 51 & 52 AND WILL KEEP
SCA FOR ZONE 50 UNTIL 15Z.
NEAR TERM: FOR SUSTAINED WINDS HAVE USED THE NAM12. FOR WAVES:
BUOY OBSERVATIONS INDICATE LONG PERIOD INCOMING SWELL STILL
PRESENT FROM SOUTHEASTERLY FETCH EARLY FRIDAY. EXPECT THIS TO
SUBSIDE RAPIDLY EARLY TODAY WITH OFF-SHORE WIND WAVE BECOMING THE
PREDOMINATE WAVE SYSTEM. SEAS WILL SUBSIDE RAPIDLY TONIGHT ALONG
WITH WINDS WITH LONG PERIOD SOUTHEASTERLY WAVE SYSTEM 1-2 FEET/8
SECONDS ONCE AGAIN BECOMING PREDOMINATE.
SHORT TERM: LOOKING FOR THE POTENTIAL FOR SCA CONDITIONS TO
DEVELOP SUNDAY NIGHT INTO MONDAY ESPECIALLY FOR THE OUTER ZONES.
WINDS ARE EXPECTED TO INCREASE TO 15 TO 20 KT W/GUSTS OF 25 KTS
AND A SWELL GENERATION TAKING PLACE ALLOWING FOR SEAS TO BUILD TO
5 TO 7 FT. AS A MATTER OF FACT, SCA CONDITIONS COULD HANG ON RIGHT
INTO MONDAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE LOW PASSING
ACROSS THE MARITIMES AND STRONG HIGH PRES MOVING IN FROM THE W.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR ANZ050.
&&
$$
NEAR TERM...MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...MIGNONE/HEWITT
MARINE...MIGNONE/HEWITT
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
1102 AM EST SAT NOV 21 2015
.SYNOPSIS...
A COLD FRONT WILL SPAWN RAIN AND SNOW SHOWERS TONIGHT. SNOW
SHOWERS ON SUNDAY WILL AFFECT AREAS NORTH OF INTERSTATE 80.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRIMARY ADJUSTMENTS THIS MORNING INCLUDE INCREASE IN SKY COVER TO
REFLECT CURRENT MID-LEVEL DECK AND MODEST CHANGES TO MAXIMA GIVEN
PERSISTENT CLOUD DECK. SELY WIND IS EXPECTED TO INCREASE DURING
THE NEXT HOUR OR TWO...WHICH WILL PROVIDE A DOWNSLOPE COMPONENT
AND MAY AID IN INCREASING TEMPS SLIGHTLY VIA COMPRESSIONAL
WARMING. PREVIOUS DISCUSSION FOLLOWS...
THE PREDAWN UPDATE INCLUDED AN UPWARD BUMP IN TEMPS AND WIND GUSTS
BASED ON THE LATEST RAP AND HRR MDL SOUNDINGS WHICH INDICATE LESS
CLOUD COVER AND A HIGHER MIXING HEIGHT IN THE WARM ADVECTION
REGIME OF TODAY.
PRECIP CHANCES WILL BE ON THE INCREASE LATE THIS EVE...CUMULATING
IN LIKELY AND CATEGORICAL NUMBERS FOR THE REGION...AS A COLD FRONT
SWEEPS OUT OF THE MIDWEST WITH LOW PRESSURE DEEPENING OVR THE
GREAT LAKES.
WITH THE SFC LOW PROJECTED TO REMAIN WEST OF THE IMMEDIATE AREA...AND
WITH DRY ENCROACHMENT AND MID LEVEL TROUGH PROGRESSION...THE
PRECIP POTENTIAL IS EXPECTED TO REMAIN WITH THE ACTUAL FRONT. THE
TEMPERATURE GRADIENT IS STILL EXPECTED TO SUPPORT A CHANGE FROM
RAIN...TO SNOW SHOWERS AFTER FRONTAL PASSAGE...ALTHOUGH THE FADING
DYNAMICS PER THE WESTWARD TRACK AND RELATIVELY WARM BOUNDARY LAYER
WILL NOT BE SUPPORTIVE OF ANY SIGNIFICANT ACCUMULATION OUTSIDE OF
THE I 80 CORRIDOR AND RIDGES WHICH COULD SEE AN INCH IN THE
PREDAWN.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
ZONES NORTH OF I 80 AS WELL AS THE RIDGES WILL EXPERIENCE SOME
LINGERING SNOW SHOWER POTENTIAL INTO SUNDAY. THE BETTER
ACCUMULATION POTENTIAL...ALBEIT ON THE ORDER OF AN ANOTHER INCH
GIVEN PROJECTIONS OF A FAIRLY DEEP MIXING LAYER WITH THE LAKE
TAP...IS LIKELY TO BE CONFINED TO EXTREME NORTHERN PORTIONS OF
MERCER AND VENANGO COUNTIES GIVEN THE STRONG WESTERLY WIND
COMPONENT OF THE BOUNDARY LAYER FLOW. OTHERWISE...SUNDAY LOOKS TO
BE DRY/MAYBE SOME FLURRIES...BUT COLD WITH HIGHS FORECAST
APPROXIMATELY 10 DEGREES UNDER THE AVERAGES...WHICH WERE FORECAST
USING A GUIDANCE BLEND.
THE COLD UPPER TROUGH IS PROJECTED TO PIVOT EASTWARD WHILE A
SURFACE HIGH BUILDS OVER THE REGION ON MONDAY. A WEAK SHORTWAVE
EMBEDDED IN THE FLOW MAY PROVIDE FOR ADDITIONAL CLOUD COVER...BUT
TEMPERATURES SHOULD BEGIN TO SLOWLY MODERATE FOR THE START OF THE
WORK-WEEK.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
COLD EARLY WEEK WEATHER WITH THE AFOREMENTIONED PROGRESSIVE UPR TROUGH
IS FORECAST TO MODERATE TOWARD SEASONAL READINGS BY MIDWEEK AS HEIGHTS
RISE/FLATTEN IN ADVANCE OF ANOTHER WRN CONUS LOW. A GUIDANCE BLEND
WAS USED FOR THE LONG TERM FORECAST.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS STILL EXPECTED THROUGH THIS EVENING. LIGHT
PRECIPITATION IS EXPECTED OVERNIGHT AT MOST TERMINALS AS A
FRONTAL BOUNDARY CROSSES THE REGION...BUT UPPER-LEVEL SUPPORT WILL
WANE QUICKLY...SUGGESTING A BRIEF WINDOW FOR PRECIPITATION BEFORE
THE SYSTEM DRY SLOT BRINGS AN END TO ANY PRECIPITATION.
COLD AIR WILL INVADE LATE TONIGHT...WHICH MAY PROVIDE A VERY BRIEF
CHANGE TO LIGHT SNOW AT THE BACK EDGE OF PRECIPITATION. AS COLD
AIR DEPTH INCREASES...LAPSE RATES WILL STEEPEN CONSIDERABLY AND
WILL SUPPORT LAKE-ENHANCED PRECIPITATION...PRIMARILY AT NORTHERN
TERMINALS GIVEN WIND DIRECTION PRIMARILY FROM THE WEST. CONDITIONS
DURING THIS TIME LIKELY WILL SUPPORT IFR-MVFR FLIGHT CATEGORIES
OR LOWER...ESPECIALLY IN ANY SNOW SHOWERS.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY/...
RESTRICTIONS ARE EXPECTED TO CONTINUE THRU SUNDAY NIGHT WITH AN
EASTERN CONUS UPPER TROUGH AND COLD WNWLY FLOW.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
UPDATE...KRAMAR
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
527 AM EST SAT NOV 21 2015
.SYNOPSIS...
A REINFORCING COLD FRONT WILL SPAWN RAIN AND SNOW SHOWERS TONIGHT.
SNOW SHOWERS WILL PLAGUE AREAS NORTH OF I 80 ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE PREDAWN UPDATE INCLUDED AN UPWARD BUMP IN TEMPS AND WIND GUSTS
BASED ON THE LATEST RAP AND HRR MDL SOUNDINGS WHICH INDICATE LESS
CLOUD COVER AND A HIGHER MIXING HEIGHT IN THE WARM ADVECTION
REGIME OF TODAY.
PRECIP CHANCES WILL BE ON THE INCREASE LATE THIS EVE...CUMULATING
IN LIKELY AND CATEGORICAL NUMBERS FOR THE REGION...AS A COLD FRONT
SWEEPS OUT OF THE MIDWEST WITH LOW PRESSURE DEEPENING OVR THE
GREAT LAKES.
WITH THE SFC LOW PROJECTED TO REMAIN WEST OF THE IMMEDIATE AREA...AND
WITH DRY ENCROACHMENT AND MID LEVEL TROUGH PROGRESSION...THE
PRECIP POTENTIAL IS EXPECTED TO REMAIN WITH THE ACTUAL FRONT. THE
TEMPERATURE GRADIENT IS STILL EXPECTED TO SUPPORT A CHANGE FROM
RAIN...TO SNOW SHOWERS AFTER FRONTAL PASSAGE...ALTHOUGH THE FADING
DYNAMICS PER THE WESTWARD TRACK AND RELATIVELY WARM BOUNDARY LAYER
WILL NOT BE SUPPORTIVE OF ANY SIGNIFICANT ACCUMULATION OUTSIDE OF
THE I 80 CORRIDOR AND RIDGES WHICH COULD SEE AN INCH IN THE
PREDAWN.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
ZONES NORTH OF I 80 AS WELL AS THE RIDGES WILL EXPERIENCE SOME
LINGERING SNOW SHOWER POTENTIAL INTO SUNDAY. THE BETTER
ACCUMULATION POTENTIAL...ALBEIT ON THE ORDER OF AN ANOTHER INCH
GIVEN PROJECTIONS OF A FAIRLY DEEP MIXING LAYER WITH THE LAKE
TAP...IS LIKELY TO BE CONFINED TO EXTREME NORTHERN PORTIONS OF
MERCER AND VENANGO COUNTIES GIVEN THE STRONG WESTERLY WIND
COMPONENT OF THE BOUNDARY LAYER FLOW. OTHERWISE...SUNDAY LOOKS TO
BE DRY/MAYBE SOME FLURRIES...BUT COLD WITH HIGHS FORECAST
APPROXIMATELY 10 DEGREES UNDER THE AVERAGES...WHICH WERE FORECAST
USING A GUIDANCE BLEND.
THE COLD UPPER TROUGH IS PROJECTED TO PIVOT EASTWARD WHILE A
SURFACE HIGH BUILDS OVER THE REGION ON MONDAY. A WEAK SHORTWAVE
EMBEDDED IN THE FLOW MAY PROVIDE FOR ADDITIONAL CLOUD COVER...BUT
TEMPERATURES SHOULD BEGIN TO SLOWLY MODERATE FOR THE START OF THE
WORK-WEEK.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
COLD EARLY WEEK WEATHER WITH THE AFOREMENTIONED PROGRESSIVE UPR TROUGH
IS FORECAST TO MODERATE TOWARD SEASONAL READINGS BY MIDWEEK AS HEIGHTS
RISE/FLATTEN IN ADVANCE OF ANOTHER WRN CONUS LOW. A GUIDANCE BLEND
WAS USED FOR THE LONG TERM FORECAST.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH MOST OF TODAY. A COLD FRONT
IS PROGGED FOR A LATE AFTERNOON/EVENING PASSAGE WITH A FEW SHOWERS
AND CONDITIONS DETERIORATION TO MVFR NEAR AND BEHIND THE
FRONT....WITH A PERIOD OF GUSTY W WINDS.
OUTLOOK...SATURDAY NIGHT THROUGH WEDNESDAY/...
RESTRICTIONS ARE EXPECTED TO CONTINUE THRU SUNDAY NIGHT WITH AN
EASTERN CONUS UPPER TROUGH AND COLD W-NW FLOW.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
15/22
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
603 AM CST SAT NOV 21 2015
.SHORT TERM: (Through Tonight)
Issued at 255 AM CST Sat Nov 21 2015
Ongoing precipitation will continue through early afternoon,
eventually tapering off from west to east due to strong
subsidence behind a cold front. A few snowflakes could mix in
with the rain at times almost anywhere across the CWA, especially
just as the rain is ending because that is when the colder air
will also be arriving. However, only the far northern CWA appears
to stay cold enough for long enough to see any accumulation, and
likely only a dusting at best.
Strong CAA behind the aforementioned cold front will produce
falling temperatures during the day across most of the area. The
exception may be across the far eastern CWA where temperatures
could remain steady or perhaps rise by a degree or two before the
front arrives.
Very windy conditions are expected today, especially for the
first few hours after fropa. A tight pressure gradient will lead
to sustained winds of 15-25 mph, and stronger winds aloft will mix
down and produce gusts of 30-40 mph. These values are consistent
with upstream METARs early this morning. BUFKIT soundings from
the RAP and the NAM do suggest that the wind gusts could even be
a bit higher than currently forecast, which would approach
criteria for a wind advisory. However, it does not appear that
wind gusts of that magnitude will be widespread enough to warrant
issuing a wind advisory, therefore no wind headlines are planned
attm. The next shift may revisit the need for wind headlines based
on observational trends. Winds should diminish quickly this
evening.
The coldest temperatures of the season so far are expected
tonight and early tomorrow morning. Overnight lows will likely
drop into the upper teens to lower 20s across the area. Overnight
temperatures would be even lower if it weren`t for the expected
mid/high clouds ahead of a secondary vort max dropping through the
upper trough tonight. These clouds will interfere with radiational
cooling processes.
Kanofsky
.LONG TERM: (Sunday through Friday)
Issued at 255 AM CST Sat Nov 21 2015
A surface high pressure center will be located south of the area
this weekend, keeping winds from the west or west-southwest until
the surface ridge moves farther eastward during the early or
middle part of the week. At that point, winds will likely become
southerly ahead of a developing low pressure system, bringing
warmer air back into the region. Unlike the 00z runs on the last
two days, the current ECMWF/GFS/GEM 00z model runs are in
remarkably good agreement on large scale atmospheric features
through 00z Wed. The primary features of interest are a large,
complex low pressure system over NV/UT and broad southwesterly
flow aloft over MO/IL. Model solutions quickly diverge thereafter,
and confidence in the forecast beyond Tuesday is low.
Kanofsky
&&
.AVIATION: (For the 12z TAFs through 12z Sunday Morning)
Issued at 544 AM CST Sat Nov 21 2015
Surface low nearly on top of STL area attm, with strong pressure
gradient in the wake of the low center really beginning to ramp
up the winds over western sections of the CWA. Rain continues to
work east-northeast in a broad swath from sw MO into s IL, with
the back edge of the rain shield nearly coincident with low level
temps necessary to support snow.
Over the next few hours...band of IFR cigs beneath and west of
the low should sweep into STL Metro TAFS with rain
continuing. Precip here should generallly remain liquid, although
a very brief switch to snow may occur by mid morning before the
precip comes to an end. Meanwhile, at KUIN and KCOU it appears
that low level AMS is just now getting cold enough to support
snow, and there could be a brief period of IFR vsbys with this
brief shot of snow. Ceilings will lift into the MVFR range by
midday, with this cloud deck then clearing from west to east
during the afternoon.
Northwest winds will be gusting to around 35kts throughout the
morning in the wake of the low, with a gradual decrease in speeds
expected during the afternoon.
Specifics for KSTL: IFR cigs will develop/advect into the area
shortly, with the rain possibly changing over to a brief period of
snow before ending around mid morning. As surface low pulls away,
cigs should increase into the MVFR range from late morning into
the afternoon, with this cloud deck clearing by sunset.
Winds will increase rapidly over the next few hours, and expect
northwest winds to gust to around 35kts from mid morning into
early afternoon, with a slow decrease heading into the early
evening hours.
Truett
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
431 AM CST SAT NOV 21 2015
.SHORT TERM: (Through Tonight)
Issued at 255 AM CST Sat Nov 21 2015
Ongoing precipitation will continue through early afternoon,
eventually tapering off from west to east due to strong
subsidence behind a cold front. A few snowflakes could mix in
with the rain at times almost anywhere across the CWA, especially
just as the rain is ending because that is when the colder air
will also be arriving. However, only the far northern CWA appears
to stay cold enough for long enough to see any accumulation, and
likely only a dusting at best.
Strong CAA behind the aforementioned cold front will produce
falling temperatures during the day across most of the area. The
exception may be across the far eastern CWA where temperatures
could remain steady or perhaps rise by a degree or two before the
front arrives.
Very windy conditions are expected today, especially for the
first few hours after fropa. A tight pressure gradient will lead
to sustained winds of 15-25 mph, and stronger winds aloft will mix
down and produce gusts of 30-40 mph. These values are consistent
with upstream METARs early this morning. BUFKIT soundings from
the RAP and the NAM do suggest that the wind gusts could even be
a bit higher than currently forecast, which would approach
criteria for a wind advisory. However, it does not appear that
wind gusts of that magnitude will be widespread enough to warrant
issuing a wind advisory, therefore no wind headlines are planned
attm. The next shift may revisit the need for wind headlines based
on observational trends. Winds should diminish quickly this
evening.
The coldest temperatures of the season so far are expected
tonight and early tomorrow morning. Overnight lows will likely
drop into the upper teens to lower 20s across the area. Overnight
temperatures would be even lower if it weren`t for the expected
mid/high clouds ahead of a secondary vort max dropping through the
upper trough tonight. These clouds will interfere with radiational
cooling processes.
Kanofsky
.LONG TERM: (Sunday through Friday)
Issued at 255 AM CST Sat Nov 21 2015
A surface high pressure center will be located south of the area
this weekend, keeping winds from the west or west-southwest until
the surface ridge moves farther eastward during the early or
middle part of the week. At that point, winds will likely become
southerly ahead of a developing low pressure system, bringing
warmer air back into the region. Unlike the 00z runs on the last
two days, the current ECMWF/GFS/GEM 00z model runs are in
remarkably good agreement on large scale atmospheric features
through 00z Wed. The primary features of interest are a large,
complex low pressure system over NV/UT and broad southwesterly
flow aloft over MO/IL. Model solutions quickly diverge thereafter,
and confidence in the forecast beyond Tuesday is low.
Kanofsky
&&
.AVIATION: (For the 06z TAFs through 06z Saturday Night)
Issued at 1127 PM CST Fri Nov 20 2015
Occasional light rain will affect the terminals overnight
tonight. Ceilings should quickly lower later tonight at KCOU and
KUIN behind the inverted trough from VFR down to IFR. Still
thinking a changeover from rain to snow at KUIN around 1200 UTC
and KCOU at 1300 UTC. Northwest winds will be quite gusty during
Saturday morning...on the order of 30-35 knots. Ceilings will be
slow to improve during the day on Saturday but do look to scatter
out by late Saturday afternoon along with winds becoming lighter.
A clear sky and light NW winds are expected for Saturday night.
Specifics for KSTL:
Occassional light rain will affect the terminal overnight
tonight. Ceilings should quickly lower toward 1200 UTC from VFR
down to IFR behind after surface low passes just to south of KSTL.
Northwest winds will be quite gusty as well by late Saturday
morning...on the order of 30-35 knots. Cannot rule out some wet
snowflakes mixing in with rain or some flurries toward tail end of
precipitation...but left mention out for now. Ceilings will be
slow to improve during the day on Saturday but do look to scatter
out around 2100 UTC Saturday afternoon along with winds becoming
lighter. A clear sky and light NW winds are expected for Saturday
night.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
959 AM EST SAT NOV 21 2015
.SYNOPSIS...
LOW PRESSURE WILL LIFT NORTHEAST ACROSS THE GREAT LAKES TODAY
WITH A TRAILING COLD FRONT SWEEPING EAST ACROSS THE REGION THIS
AFTERNOON. RAIN SHOWERS WILL CHANGE TO SNOW SHOWERS OR FLURRIES
BEFORE ENDING TONIGHT. MUCH COLDER AIR WILL SETTLE IN BEHIND THE
FRONT FOR THE END OF THE WEEKEND. A WARMING TREND WILL THEN RETURN
BY THE FIRST OF THE WEEK INTO THE THANKSGIVING HOLIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY MINOR CHANGES TO GRIDS THIS MORNING AS SURFACE LOW STILL
REMAINS ON TRACK TO BE AROUND KDAY AT 18Z. CURRENT SURFACE
ANALYSIS FROM THIS MORNING SHOWS THE SURFACE LOW CURRENTLY IN
SOUTHERN ILLINOIS WITH A COLD FRONT TRAILING OFF TO THE
SOUTHEAST. THERE WAS ALSO A WEAK WARM FRONT ACROSS NORTHERN
KENTUCKY. DEWPOINTS NORTH OF THE COLD FRONT WERE MAINLY AROUND 20
DEGREES WHILE SOUTH OF THE WARM FRONT AT OR ABOVE 30 DEGREES. KILN
12Z SOUNDING ALSO SHOWS A GOOD DEAL OF DRY AIR BETWEEN 700 AND
1000 MB. FORECAST SOUNDINGS SHOW THE LAYER SLOWLY SATURATING WITH
WEAK WET BULBING FIGHTING WAA AS THE WARM FRONT PUSHES NORTH.
LOOKING AT RAP CRITICAL THICKNESSES IT SEEMS LIKE MOST OF THE
AREA WILL INITIALLY BE RAIN EXCEPT FOR THE POSSIBILITY OF OUR FAR
NORTHERN COUNTIES (DEPENDING ON THE EXACT TRACK OF THE SURFACE LOW
AND WARM FRONT). AS THE FRONT PASSES THERE WILL BE A BRIEF PERIOD
OF RAIN CHANGING OVER TO A RAIN/SNOW MIX AND THEN SNOW. DRIER MID
LEVEL AIR WILL THEN QUICKLY MOVE IN BEHIND THE FRONT. FORECAST
SOUNDINGS STILL SHOW LOW LEVEL SATURATION WHICH WOULD SUPPORT
FLURRIES BEHIND THE FRONT. WIND GUSTS UP TO 35 MPH CAN ALSO BE
EXPECTED ALONG AND BEHIND THE FRONT.
PREV DISCUSSION ->
MID LEVEL ENERGY DROPPING SE INTO THE PLAINS WILL ACT TO SHARPEN
UP AND CARVE OUT A TROF OVER THE NATIONS MID SECTION. AN EMBEDDED
S/W TO ROTATE AROUND THE EAST SIDE OF THIS LONG WAVE TROF THRU THE
MID MS VLY THIS MORNING AND INTO THE GREAT LAKES BY EVENING.
ASSOCIATED SFC LOW OVER THE MID MS VLY TO EJECT NE INTO SW OHIO BY
18Z AND THEN INTO THE EASTERN GREAT LAKES BY EVENING. NUMERICAL
MODEL SOLNS HAVE CLUSTERED COMING INTO BETTER AGREEMENT WITH SFC
LOW NEAR JUST WEST OF DAYTON AT 18Z. COMPARED TO THE 12Z
RUNS...THESE SOLNS HAVE GENERALLY TRENDED FURTHER SOUTH CLOSER TO
THE CONSISTENT ECMWF...ALLOWING FOR A QUICKER CHANGE OVER AND A
LTL MORE SNOW. WILL ALLOW PCPN TO DEVELOP BY AFTN ACROSS THE
WESTERN COUNTIES AND SPREAD EAST. STRONG CAA DEVELOPS WITH 8H
TEMPS GOING FROM AT OR ABOVE 5 DEG C TO -6 DEG C IN THE WEST BY
00Z. WILL BUMP UP SNOW TO AROUND 1 INCH ACROSS THE FAR NW TO ABOUT
ONE TENTH OF AN INCH ON GRASSY AREAS AT ILN. WILL SHOW NON-
DIURNAL TEMPERATURE TREND WITH READINGS FALLING INTO THE 30S IN
THE WEST LATE IN THE DAY. EXPECT WEST WIND GUSTS UP TO 35 MPH WITH
THE FRONTAL PASSAGE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
STRONG SFC COLD FRONT EXPECTED TO PUSH THRU ILN/S EASTERN COUNTIES
DURG THE EARLY EVENING. STRONG CAA TO DEVELOP WITH 8H TEMPS TO
BETWEEN -8 AND -11 DEG C BY SUNDAY MORNING. EXPECT PCPN TO MIX
WITH AND CHANGE TO SNOW ACRS THE ENTIRE FA EARLY TONIGHT. BASED ON
BETTER AGREEMENT OF SOLNS MORE IN LINE WITH COLDER FURTHER SOUTH
ECMWF SOLN...HAVE INCREASED SNOW TO AROUND 1 INCH ACRS THE FAR NW
TO A TENTH OF AN INCH AT ILN. FURTHER SOUTH...EXPECT LITTLE OR NO
ACCUMULATION. EXPECT PCPN TO END OR DIMINISH TO FLURRIES BY LATE
EVENING. AS SFC LOW LIFTS NE INTO SE CANADA...EXPECT DRY SLOW TO
PUSH INTO SW OHIO. WILL ALLOW CLOUDS TO DECREASE ACRS THE WEST
LATE. THE COLDEST AIR OF THE SEASON WILL SETTLE INTO THE OHIO
VALLEY AS SFC HIGH PRESSURE BUILD INTO THE OHIO VALLEY SUNDAY.
EXPECT SAT NIGHTS LOWS TO RANGE FROM THE UPPER TEENS FAR NW TO THE
UPPER 20S SE. SUNDAY WILL OFFER COLD TEMPERATURES WITH A GOOD
AMOUNT OF SUNSHINE. EXPECT SUNDAYS HIGHS TO RANGE FROM THE UPPER
20S NW TO THE MID/UPR 30S SE. TEMPERATURES WILL MODERATE ON THE
BACK SIDE OF THE HIGH MONDAY WITH READINGS FROM NEAR 40 NW TO THE
MID 40S SE.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER LEVEL TROUGH WILL CROSS THE NORTHERN OHIO VALLEY EARLY MONDAY
AND INCREASE CLOUD COVER HERE WITH GENERALLY SUNNY SKIES TO THE
SOUTH. THE AXIS OF THE SURFACE HIGH WILL PASS EAST OF THE REGION
OVERNIGHT MONDAY AND RETURN FLOW WILL PERMIT A WARMING TREND FOR
NEXT WEEK.
MODELS DIVERGE SIGNIFICANTLY ON THURSDAY NIGHT AS A LONGWAVE TROUGH
RUNS FROM JAMES BAY CANADA TO CALIFORNIA AND A SURFACE FRONT LAYS
OUT FROM TX TO SOUTH OF HUDSON BAY. GFS IS PROGRESSIVE WITH THE
UPPER LOW AND PULLS THE SURFACE LOW INTO CANADA...SWEEPING THE FRONT
THROUGH THE OHIO VALLEY LATER FRIDAY AND OVERNIGHT. THE EUROPEAN
DISJOINTS THE UPPER SYSTEM AND CUTS OFF A H5 CLOSED LOW IN THE GREAT
BASIN WITH A SOMEWHAT PROGRESSIVE NORTHERN S/W PEELING OFF OF THIS
AND CROSSING THE GREAT LAKES OVERNIGHT FRIDAY. THIS KEEPS THE
SURFACE FRONT OVER THE MIDWEST AND PULLS ENERGY NORTHEAST AND AWAY
FROM THE OHIO VALLEY FOR FRIDAY AND OVERNIGHT.
BLENDED THE TWO BUT KEPT FORECAST AREA IN LOW CHANCE POPS ON
FRIDAY...INCREASING THEM BEYOND VALID FORECAST PERIOD.
FORECAST UNCERTAINTY ON FRIDAY IS HIGH AFTER THURSDAY NIGHT DUE TO
THESE DIFFERENCES IN MODELS. TEMPS AT THE END OF THE WEEK SHOULD
RISE INTO AT LEAST THE 50S AND COULD PULL INTO THE 60S IF THE DRIER
EUROPEAN VERIFIES. CLOUDY AND RAINY GFS VERIFICATION WILL LIMIT
HIGHS THIS DAY. TOOK A MIDDLE OF THE ROAD APPROACH BEING THIS FAR
OUT.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
TAF SITES WILL STAY UNDER VFR THROUGH THE EARLY PART OF THE
FORECAST AS HIGH PRESSURE MOVES EAST. CONDITIONS WILL DETERIORATE
AFTER 18Z WHEN RAIN SHOWERS WITH MVFR WILL MOVE IN AHEAD OF A
STRONG COLD FRONT. SNOW SHOWERS WITH MVFR ARE LIKELY STARTING AT
22Z WHEN COLDER AIR ARRIVES WITH FRONTAL PASSAGE AND A WIND SHIFT
TO WEST. GUSTS OVER 30 KNOTS WILL BE POSSIBLE ALONG AND BEHIND THE
FRONT ESPECIALLY AT DAY. SNOW SHOWERS WILL END AND WINDS WILL
SLOWLY SUBSIDE AFTER 02Z SUNDAY. CVG WILL SEE SCT CLOUDS AND
DECREASING NORTHWEST WINDS AFTER 12Z SUNDAY.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HAINES/AR
NEAR TERM...HAINES/AR
SHORT TERM...AR
LONG TERM...FRANKS
AVIATION...CONIGLIO
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
953 AM EST SAT NOV 21 2015
.SYNOPSIS...
A COLD FRONT CROSSES TONIGHT...MAKING THE SECOND HALF OF THE
WEEKEND MUCH COLDER THAN THE FIRST...WITH MAINLY MOUNTAIN SNOW
SHOWERS. HIGH PRESSURE NEXT WEEK WITH MODERATING TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
945 AM UPDATE...
RAISED TEMPS A FEW DEGREES THIS AFTN OVER THE LOWLANDS. WINDS WILL
PICK UP AHEAD OF THE FRONT AND ESPECIALLY JUST BEHIND THE FRONT
WHERE BUFKIT AND HRRR SUGGESTS 30 TO 35 KT GUSTS THIS EVENING.
AS FOR FIRE CONCERNS...THERE MAY BE ENOUGH OF A REBOUND IN RH
THIS AFTERNOON AS THE WINDS PICK UP TO MITIGATE NEEDING A FIRE
SPS. WILL CONTINUE TO MONITOR TRENDS OVER THE NEXT FEW HRS.
PREV DISCN...
LOW PRESSURE CENTER APPROACHES FROM THE LOWER OHIO
VALLEY TODAY. IT TAKES A LEFT HAND TURN THIS AFTERNOON...REACHING
THE UPPER OHIO VALLEY THIS EVENING...AS ITS ASSOCIATED UPPER LEVEL
S/W TROUGH ROUNDS THE BASE OF THE L/W TROUGH AND STARTS COMING UP
THE E SIDE...TAKING ON A NEGATIVE TILT AS A RESULT. THE SYSTEM IS
PROGGED TO DEEPEN TO THE TUNE OF ABOUT 6 MB / HR THIS AFTERNOON
AND TONIGHT...CROSSING SERN ONTARIO AND MOVING INTO SWRN QUEBEC
TONIGHT.
THE WARM FRONT AHEAD OF THE APPROACHING LOW LIFTS NWD THROUGH THE
AREA THIS MORNING AND MIDDAY...THE ASSOCIATED MID AND HIGH CLOUD
RETREATING NWD WELL AHEAD OF THE SFC FRONT FIRST THING THIS
MORNING. THIS PLACES THE FCST AREA IN THE WARM SECTOR THIS
AFTERNOON. EXITING DRY AIR WILL RESULT IN RH VALUES DIPPING INTO
THE 20S THIS AFTERNOON ACROSS CENTRAL AND NRN WV. WITH GUSTY WARM
SECTOR WINDS THIS AFTERNOON...AND DRYING FUELS...A FIRE DANGER
STATEMENT MAY BE NEEDED...AND THE LOW PROB HWO MENTION WILL
CONTINUE FOR THIS.
SHOWERS ARRIVE JUST AHEAD OF THE COLD FRONT THIS EVENING. COLDER
AIR RUSHES IN BEHIND THE SYSTEM WITH SHARP PRESSURE RISES BEHIND
THE COLD FRONT...ENDING THE PRECIPITATION AS IT ARRIVES. THEREFORE
SEE A VERY NARROW WINDOW OF OPPORTUNITY FOR A FEW SNOW FLAKES OVER
THE LOWLANDS AS THE SHOWERS END...MORE SO N THAN S IF ANYTHING.
THERE IS...OF COURSE...A BETTER CHANCE FOR SNOW IN THE MOUNTAINS
TONIGHT...ESPECIALLY ACROSS THE HIGHER TERRAIN...AS UPSLOPE
ENHANCES LOW LEVEL LIFT DURING THE COLD ADVECTION. AMOUNTS WILL BE
LIMITED BY LACK OF DENDRITIC GROWTH...AS IT WILL TAKE THE UPSLOPE
FLOW OVER THE MOUNTAINS JUST TO GET THE TOP OF THE SATURATED UP
INTO THE -8C AND COLDER LAYER. THOUGHT OVERNIGHT POPS MAY HAVE
BEEN A BIT HIGH FOR THIS REASON BUT OPTED TO LEAVE AS IS. HAVE CUT
BACK ON SNOW AMOUNTS TO UNDER AN INCH EVEN ACROSS THE HIGHEST
RIDGES...MAYBE A TRACE ON NRN LOWLAND HILLTOPS.
USED A MET/MAV/PREV BLEND FOR HIGHS IN THE WARM SECTOR TODAY...AND
A NAM/MET/PREV BLEND FOR HOURLY TEMPERATURES TONIGHT AS THE
BAROCLINIC ZONE MOVES THROUGH...A LITTLE SLOWER ON THE COOLING
THAN PREVIOUS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
FRONT WILL BE THROUGH CWA WITH COLD AIR ADVECTION TAKING PLACE
DURING THE DAY ON SUNDAY AND CONTINUING SUNDAY NIGHT. SURFACE
HIGH PRESSURE BEGINS BUILDING IN FROM THE WEST. 5H TROUGH...WITH
85H THERMAL TROUGH FOLLOWING...WILL MOVE THROUGH DURING THE DAY
SUNDAY. LOW LEVELS DRY OUT FAIRLY QUICKLY...HOWEVER RESIDUAL
MOISTURE WITH SOME ENHANCED DYNAMICS WILL HANG ON TO ALLOW FOR THE
CONTINUATION OF A FEW SNOW SHOWERS...PERHAPS ENDING BY SUNDAY
AFTERNOON. ATMOSPHERIC COLUMN WILL CONTINUE DRYING TREND FOR THE
REST OF THE PERIOD WITH NORTHWEST FLOW USHERING COOLER AIR. WILL
SEE SOME OF THE COLDEST TEMPERATURES MONDAY MORNING. FOR
TEMPS...USED MODEL BLEND ACROSS THE BOARD...AVERAGING VALUES BACK
INTO INHERITED FORECAST.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
MODELS AND ENSEMBLES SHOWING HIGH PRESSURE OVER THE AREA FOR MONDAY
NIGHT THROUGH THURSDAY NIGHT. NEXT SYSTEM ARRIVES LATE IN THE WEEK
OR NEXT WEEKEND. CONFIDENCE IN TIMING OF THIS COLD FRONT IS LOW.
USED A BLEND OF THE GEFS AND ECMWF ENSEMBLE MEANS.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
VFR THROUGH TODAY YIELDS TO MVFR CONDITIONS FROM W TO E
TONIGHT...AS A LOW PRESSURE SYSTEM APPROACHES FROM THE LOWER OHIO
VALLEY. ITS WARM FRONT WILL MOVE NWD THROUGH THE AREA DURING THE
MORNING AND MIDDAY HOURS TODAY. THE LOW ITSELF WILL TAKE A LEFT
HAND TURN THIS AFTERNOON AND REACH THE UPPER OHIO VALLEY BY THIS
EVENING. THIS WILL BRING ITS COLD FRONT TO THE OHIO RIVER NEAR
00Z SUN AND THEN THROUGH THE MOUNTAINS BY 06Z SUN.
SHOWERS WILL ARRIVE JUST AHEAD OF...IF NOT WITH...THE COLD
FRONT...THIS EVENING...LIKELY BRINGING VSBYS DOWN TO MVFR AND
THEN CIGS DOWN TO MVFR AN HOUR OR TWO AFTER THE COLD FRONT PASSES.
THE RAIN SHOWERS WILL SWITCH OVER TO SNOW SHOWERS OVER THE
MOUNTAINS OVERNIGHT TONIGHT. VSBYS WILL IMPROVE TO VFR FROM W TO E
OVERNIGHT AS THE PRECIPITATION ENDS.
LIGHT E TO SE FLOW AHEAD OF THE WARM FRONT THIS MORNING WILL
BECOME S TO SW AND GUSTY IN THE WARM SECTOR AHEAD OF THE COLD
FRONT THIS AFTERNOON AND EVENING...AND THEN W TO SW AND STILL A
BIT GUSTY BEHIND THE COLD FRONT TONIGHT...THEN W TO NW AND
DIMINISHING A BIT TOWARD DAWN SUN. LIGHT SW FLOW ALOFT THIS
MORNING WILL BECOME MODERATE SW THIS AFTERNOON...SHIFTING TO
MODERATE W BEHIND THE COLD FRONT TONIGHT...AND THEN LIGHT TO
MODERATE NW BY DAWN SUN.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SUNDAY...
FORECAST CONFIDENCE: HIGH.
ALTERNATE SCENARIOS: ONSET AND EXTENT OF MVFR IN RAIN SHOWERS AND
CIGS MAY VARY LATE TODAY AND TONIGHT. GUSTY WINDS WILL VARY LATER
TODAY AND TONIGHT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 15 16 17 18 19 20 21 22 23 00 01 02
EST 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H H H H H H H H H H H M
HTS CONSISTENCY H H H H H H H H H M M H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H M M M
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z SUNDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KMC/TRM
NEAR TERM...TRM/30
SHORT TERM...KMC
LONG TERM...RPY
AVIATION...TRM
AREA FORECAST DISCUSSION
NWS ALBANY NY
415 PM EST SAT NOV 21 2015
.SYNOPSIS... A LOW PRESSURE WILL RACE NORTHEAST THROUGH THE EASTERN
GREAT LAKES TONIGHT...AND DRAG A COLD FRONT ACROSS THE REGION WITH
SCATTERED RAIN AND SNOW SHOWERS. ANY ACCUMULATION WILL BE CONFINED
TO RIM OF THE MOHAWK VALLEY AND ADIRONDACKS. BREEZY NORTHWEST WINDS
WILL BRING COOLER AIR BACK INTO THE AREA ON SUNDAY...ALONG WITH SOME
LAKE EFFECT SNOW SHOWERS OVER THE ADIRONDACKS. MAINLY DRY AND COLD
WEATHER IS EXPECTED ON MONDAY ALTHOUGH THERE COULD BE ADDITIONAL
SNOW SHOWERS ACROSS THE ADIRONDACKS.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 415 PM EST...STILL DRY ACROSS OUR REGION. HIGH PRESSURE JUST TO OUR
EAST WAS STILL IN CONTROL OF OUR WEATHER...WITH HIGH CLOUDS
INCREASING OVER OUR REGION AHEAD OF THE NEXT DISTURBANCE.
TEMPERATURES WERE GENERALLY IN THE 40S.
THIS DISTURBANCE WAS AN AREA OF LOW PRESSURE OVER OHIO
WHICH HAS PRODUCED A EARLY SEASON SNOWSTORM ACROSS PORTIONS
OF THE GREAT LAKES. THIS STORM WILL TRACK NORTHEASTWARD INTO
ONTARIO. IT WILL DRAG AN OCCLUDED FRONT THROUGH OUR REGION
LATE TONIGHT.
THE BEST FORCING AND MOISTURE WILL STAY WELL NORTH AND EAST
OF THE CAPITAL REGION.
INITIALLY ANY PRECIPITATION WILL START AS A RAIN SNOW MIX OVER
THE ADIRONDACKS BUT SHOULD CHANGE TO ALL SNOW OVERNIGHT. ACCUMULATIONS
LOOK MINOR AS SURFACE TEMPERATURES WILL ONLY BE MARGINALLY COLD
ENOUGH FOR ACCUMULATIONS. FOR TONIGHT WE ARE LOOKING FOR A COATING
TO TWO INCHES OVER THE ADIRONDACK PARK.
FURTHER SOUTH AND EAST SHOWERS WILL BE MOST SCATTERED. SNOW FLAKES
COULD MIX ANYWHERE BUT WILL LIKELY NOT PRODUCE ANY ACCUMULATION
AS THE QPF LOOKS VERY LIGHT WITH SOME AREAS NOT GETTING ANY MEASURABLE
AT ALL...ESPECIALLY SOUTH OF ALBANY.
OVERNIGHT LOWS WILL RANGE FROM THE UPPER 20S TO MID 30S. IN SOME CASES...
THEY MIGHT HAPPEN THIS EVENING BEFORE THICKER CLOUDS AND A BREEZE
KICKS IN WHICH BOTH MIGHT WARM THE BOUNDARY A LITTLE IN THE VALLEYS.
A SOUTH BREEZE WILL AVERAGE 5-15 MPH TONIGHT BECOME WESTERLY BY
DAYBREAK AS THE FRONT MOVES ON BY.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
AS THE FRONT MOVES ON BY...CHILLIER AIR WILL FILTER INTO THE REGION.
HOWEVER...WITH A WSW FLOW AND A GOOD DEAL OF SUNSHINE...TEMPERATURES
WILL ACTUALLY WARM TO NEAR 50 IN THE VALLEYS...WHILE HOLDING CLOSER
TO 40 ACROSS THE HIGHER TERRAIN. KEEP IN MIND THESE VALUES MIGHT
HAPPEN BY MIDDAY...WITH TEMPERATURES FALLING A BIT DURING THE
AFTERNOON.
IT WILL BE BREEZY WITH A WEST WIND 10-15 MPH...GUSTING TO 25 MPH
ESPECIALLY OVER THE HIGHER TERRAIN/MOHAWK VALLEY AND THE CAPITAL REGION.
WHILE MOST OF THE AREA WILL BE DRY WITH PARTIAL SUNSHINE...LAKE ENHANCED
CLOUDS AND PERHAPS SOME SNOW SHOWERS WILL PERSIST OVER
THE ADIRONDACKS. EVEN IF SURFACE TEMPERATURES ARE ABOVE FREEZING
ON SUNDAY...THE AIR WILL BE QUITE CHILLY ALOFT AND CERTAINLY VERTICAL
INSTABILITY AND UPSLOPE COULD GENERATE THESE SNOW SHOWERS EVEN IN
THE ABSENCE OF ANY PURE LAKE EFFECT.
HOWEVER...AFTER EXAMINING THE EXPERIMENTAL KVIE CSTAR PROGRAM...
IT NOW APPEARS THE INLAND LAKE EXTENT OFF OF ONTARIO WILL ONLY
BE ABOUT 50 MILES...LIMITED DUE TO SOME SHEAR IN THE COLUMN AND
DRY AIR IN THE MID LEVELS. THEREFORE PURE LAKE EFFECT SNOW
PLUMES MIGHT ONLY GRAZE HERKIMER AND LIKELY NOT EVEN REACH
HAMILTON COUNTIES. THEREFORE NO HEADLINES WERE ISSUED.
IF CONDITIONS LOOK DIFFERENT LATER ON...HEADLINES WILL BE RECONSIDERED.
ANY ADDITIONAL SNOW ACCUMULATIONS ON SUNDAY OVER THE ADIRONDACKS SHOULD
LIGHT...AN INCH OR LESS.
SUNDAY NIGHT THROUGH MONDAY NIGHT...LARGE HIGH PRESSURE WILL
BUILD TO OUR SOUTH. ADDITIONAL SHORT WAVE ENERGY ALONG
WITH ANOTHER MID LEVEL TROUGH ROLLING TO OUR NORTH...
COULD TRIGGER A FEW MORE BOUTS OF SNOW SHOWERS WITH ADDITIONAL
MAINLY MINOR ACCUMULATIONS OVER OUR ADIRONDACKS AND
PERHAPS CENTRAL MOHAWK VALLEY. THIS AGAIN ASSUMES THE MAIN
PLUMES OFF ONTARIO STAY MAINLY TO OUR WEST. IT WILL BE A CLOSE
CALL BUT RIGHT NOW THEY APPEAR TO JUST MISS MOST OF OUR AREA.
THE POTENTIAL IS THERE FOR 1-4 INCHES OF SNOWFALL WHEN IT IS ALL SAID AND
DONE...SPREAD OUT OVER SEVERAL PERIODS SO AGAIN NO LAKE EFFECT SNOW
ADVISORIES WERE ISSUED WITH THIS PACKAGE. KEEP IN MIND IF ANY
PLUME FROM LAKE ONTARIO WAS ABLE TO PENETRATE INTO HERKIMER OR
HAMILTON COUNTIES...AMOUNTS COULD BE LOCALLY A LITTLE HIGHER.
THE REMAINDER OF THE REGION SHOULD REMAIN MOSTLY DRY ALTHOUGH A SPRINKLE
OR FLURRY IS POSSIBLE ALONG WITH OCCASIONAL CLOUDINESS.
OTHERWISE IT LOOKS CHILLY BUT NOTHING OUT OF THE ORDINARY
FOR LATE NOVEMBER.
LOW TEMPERATURES MONDAY MORNING WILL BE MAINLY IN THE 20S...WITH SOME TEENS
IN THE COLDEST AREAS. HIGHS MONDAY WILL BE ONLY IN THE UPPER 20S TO MID 30S
HIGHER TERRAIN...CLOSE TO 40 IN THE VALLEYS.
BY TUESDAY...AS HIGH PRESSURE SLOWLY BEGINS TO BUILD ALOFT...THERE WILL BE
SLOW MODERATION IN THE AIRMASS. ANY LINGERING SNOW SHOWERS WILL
CEASE ACROSS THE ADIRONDACKS. OTHERWISE IT WILL BE MOSTLY SUNNY.
LOWS TUESDAY MORNING WILL RANGE FROM THE MID TEENS TO MID 20S.
HIGHS TUESDAY WILL RANGE FROM THE 30S OVER THE HIGHER TERRAIN...
LOWER TO MID 40S IN THE VALLEYS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE LONG TERM PERIOD WILL BE CHARACTERIZED BY MAINLY DRY WEATHER
WITH THE NEXT CHANCE FOR PRECIPITATION ACROSS THE REGION FRIDAY INTO
SATURDAY AS A FRONTAL BOUNDARY MOVES ACROSS THE REGION.
AT THE START OF THE LONG TERM PERIOD...THE LONG RANGE GUIDANCE
CONTINUES TO BE IN VERY GOOD AGREEMENT WITH THE EVOLUTION OF THE
LONG TERM PATTERN. MUCH OF THE LONG TERM PERIOD WILL BE DOMINATED BY
HIGH PRESSURE AT THE SURFACE AND UPPER-LEVEL RIDGING ALOFT. THIS
WILL RESULT IN AN EXTENDED PERIOD OF DRY WEATHER TUESDAY NIGHT
THROUGH THURSDAY NIGHT...INCLUDING THANKSGIVING...WITH PARTLY CLOUDY
SKIES.
A FRONTAL BOUNDARY WILL MOVE ACROSS THE REGION FRIDAY INTO THE
SATURDAY TIME PERIOD. THERE IS SOME DIFFERENCE IN THE LONG RANGE
GUIDANCE REGARDING THE TIMING OF THIS FRONTAL BOUNDARY...BUT HAVE
INDICATED CHANCE POPS DURING THIS TIMEFRAME FOR RAIN SHOWERS DURING
THE DAYTIME HOURS...AND A MIX OF RAIN/SNOW SHOWERS DURING THE
NIGHTTIME HOURS WITH THE BEST CHANCE FOR SNOW ACROSS THE HIGHER
TERRAIN.
TEMPERATURES DURING THE LONG TERM PERIOD WILL BE SLIGHTLY ABOVE
NORMAL FOR LATE NOVEMBER. HIGHS ON WEDNESDAY WILL RANGE FROM THE
UPPER 30S/LOW 40S ACROSS THE HIGHER TERRAIN TO THE MID AND UPPER 40S
IN VALLEY AREAS. HIGHS ON THURSDAY AND FRIDAY WILL RANGE FROM THE
UPPER 40S TO MID 50S. HIGHS ON SATURDAY WILL RANGE FROM NEAR 40 TO
NEAR 50. LOWS TUESDAY NIGHT WILL RANGE FROM THE MID TO UPPER
20S...UPPER 20S TO LOWER 30S WEDNESDAY NIGHT...AND MID 30S TO NEAR
40 THURSDAY AND FRIDAY NIGHTS.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH THE DAY TODAY...LOWERING TO
MVFR LATER THIS EVENING AS STRATUS WORKS IN FROM THE SOUTH.
A VARIABLE WIND WILL BECOME SOUTH AROUND 10KTS LATER THIS
AFTERNOON OR EARLY EVENING.
A SYSTEM WILL BRING THE CLOUDS THIS EVENING AND SOME SCATTERED
RAIN SHOWERS...POSSIBLY MIXING WITH SNOW FLAKES LATER TOWARD
DAYBREAK. FOR NOW...WE WILL ONLY WENT VCSH INTO EARLY SUNDAY.
A FRONT WILL PASS THROUGH SHIFTING THE WIND TO THE WEST AROUND
10KTS WITH GUSTS TO 20KTS AT KPSF AND KALB. CONDITIONS WILL RETURN
TO VFR WITH GOOD VISIBILITY AT THE TAF SITES SUNDAY.
OUTLOOK...
SUNDAY NIGHT-THANKSGIVING DAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A FRONTAL SYSTEM WILL BRING SOME SHOWERS OF RAIN AND SNOW TONIGHT...
HEAVIEST ACROSS THE ADIRONDACKS WHERE A COUPLE INCHES OF SNOW
COULD ACCUMULATE. OTHERWISE...RAIN SHOWER AMOUNTS WILL BE
VERY LIGHT...WELL UNDER A QUARTER INCH MOST PLACES.
ASIDE FROM ON GOING SNOW SHOWERS ACROSS THE ADIRONDACKS...
THE REMAINDER OF THE REGION LOOKS MAINLY DRY SUNDAY THROUGH
THANKSGIVING DAY. EACH NIGHT WILL SEE A NEAR RECOVERY
OF RR VALUES...DROPPING TO SEASONABLE LEVELS IN THE 40S AND
50S EACH AFTERNOON. AMOUNTS WILL BE HIGHER ACROSS THE ADIRONDACKS
WHERE THERE WILL BE POSSIBLE PRECIPITATION...GENERALLY
IN THE 50S AND EVEN 60S.
IT WILL BE SOMEWHAT BREEZY ON SUNDAY...WITH A WESTERLY
WIND 10-15 MPH WITH GUSTS TO 25 MPH ACROSS THE HIGHER
TERRAIN/MOHAWK VALLEY AND CAPITAL REGION.
THE WIND WILL GENERALLY BE LIGHTER THROUGH THE REMAINDER OF THE WEEK.
THE NEXT CHANCE OF WIDESPREAD PRECIPITATION AFTER TONIGHT DOES NOT
APPEAR TO BE UNTIL LATE FRIDAY OR SATURDAY.
&&
.HYDROLOGY...
NO HYDROLOGY ISSUES ARE EXPECTED THROUGH THE NEXT WEEK. OTHER THAN
THE POTENTIAL FOR SCATTERED SHOWERS TONIGHT AND LAKE
ENHANCED SNOW SHOWERS IN HAMILTON AND HERKIMER COUNTIES SUNDAY...THE
PERIOD WILL BE MAINLY DRY THROUGH FRIDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...IRL
AVIATION...HWJIV
FIRE WEATHER...HWJIV
HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
338 PM EST SAT NOV 21 2015
.SYNOPSIS...
LOW PRESSURE LOCATED OVER WESTERN OHIO THIS AFTERNOON WILL
PROGRESS NORTHEASTWARD AND INTO QUEBEC ON SUNDAY. THE LOW IS
FORECAST TO PULL A COLD FRONT THROUGH OUR AREA LATE TONIGHT. HIGH
PRESSURE SHOULD NOSE INTO OUR REGION FROM THE SOUTHWEST FOR SUNDAY
INTO MONDAY. THE HIGH IS EXPECTED TO BE LOCATED OVER THE
SOUTHEASTERN STATES ON MONDAY NIGHT. THE CENTER OF THE AIR MASS IS
ANTICIPATED TO MOVE NORTHEASTWARD AND IT SHOULD REACH CANADA`S
MARITIME PROVINCES ON WEDNESDAY. THE HIGH SHOULD CONTINUE TO
INFLUENCE OUR WEATHER INTO FRIDAY. A COLD FRONT APPROACHING FROM
THE NORTHWEST IS FORECAST TO ARRIVE ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AT LATE-DAY AN AREA OF HIGH PRESSURE WAS PULLING AWAY FROM OUR
REGION TO THE NORTHEAST AS STRENGTHENING LOW PRESSURE WAS TRACKING
FROM THE UPPER OHIO VALLEY TOWARD THE EASTERN GREAT LAKES. A COLD
FRONT EXTENDED DOWN FROM THE OHIO VALLEY AND INTO THE SOUTHEAST
STATES. THIS BOUNDARY WILL BE APPROACHING OUR AREA LATER TONIGHT,
AND CLOUDS WILL CONTINUE TO THICKEN AND LOWER THROUGH THIS
EVENING. NAM/GFS DATA AS WELL AS THE HRRR AND RAP OVERALL SHOW
DISORGANIZED, WIDELY SCATTERED SHOWERS ASSOCIATED WITH THE FRONT,
MAINLY AFTER MIDNIGHT, AS IT SWEEPS WEST TO EAST ACROSS THE
FORECAST AREA. THE SPEED OF THE FRONT THROUGH THE AREA AND
SOMEWHAT LIMITED MOISTURE ASSOCIATED WITH IT WILL LIMIT OVERALL
PRECIP CHANCES AND AMOUNTS. CURRENT MODEL GUIDANCE CONTINUES TO
FOCUS A BETTER CHANCE FOR SHOWERS FOR THE NORTHERN THIRD OF THE
FORECAST AREA INTO THE POCONOS, LEHIGH VALLEY, AND NORTHERN NEW
JERSEY, AND WE HAVE KEPT LOW CHANCE POPS FOR THESE AREAS, WITH
MAINLY SLIGHT CHANCE ELSEWHERE. IN ADDITION, THERE IS THE
POSSIBILITY FOR SOME WET SNOW TO MIX IN WITH THE RAIN SHOWERS
ACROSS THE FAR NORTH BEFORE THE PRECIP ENDS DEPENDING ON HOW
QUICKLY THE COLDER AIR ARRIVES BEHIND THE PASSING FRONT. OVERALL
QPF AMOUNTS WITH THIS FRONT WILL BE LIGHT, WITH ONLY A FEW
HUNDREDTHS OF AN INCH ANTICIPATED. MINIMUM TEMPERATURES ARE
EXPECTED TO RANGE MOSTLY FROM THE LOWER 40S SOUTH TO THE MIDDLE
30S NORTH, WITH PERHAPS THE HIGHER TERRAIN IN THE POCONOS DROPPING
INTO THE LOWER 30S.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
THE PREVIOUSLY MENTIONED COLD FRONT WILL BE TO OUR EAST AND
OFFSHORE INTO SUNDAY MORNING AS AN AREA OF LOW PRESSURE DEVELOPS
ALONG THE BOUNDARY WELL TO OUR SOUTH, OFF THE COAST OF THE
CAROLINAS. THIS LOW IS FORECAST TO REMAIN OFFSHORE AS IT
PROGRESSES FARTHER NORTHEAST AND OUT TO SEA LATER SUNDAY TO SUNDAY
EVENING. WHILE WE ARE EXPECTING THINNING CLOUDS AND CLEARING
CONDITIONS FOR MUCH OF THE FORECAST AREA DURING THE MORNING,
CLOUDS AND A FEW SHOWERS MAY HANG ON AT THE COAST THROUGH ABOUT
MIDDAY OR SO AS SOME MOISTURE GETS DRAWN NORTHWARD IN THE
SOUTHWEST FLOW ALOFT AHEAD OF THE LOW PRESSURE. OVERALL, WE KEPT
CHANCE POPS IN PLACE THROUGH THE MORNING AT THE COAST AND FOR OUR
COASTAL WATERS.
IN TERMS OF TEMPERATURES AND WINDS, SOME OF THE COOLEST AIR OF
THE AUTUMN SEASON THUS FAR WILL BEGIN SPREADING ACROSS THE REGION
ON GUSTY NORTHWESTERLY WINDS, GUSTING AT TIMES TO AROUND 25 MPH.
WE MOSTLY TOOK A BLEND OF MET/MAV GUIDANCE WITH CONTINUITY FOR
MAXIMUM TEMPERATURES, AND WE EXPECT HIGHS TO MAINLY BE IN THE
UPPER 40S TO LOWER 50S ACROSS THE REGION, WITH ONLY LOWER 40S
EXPECTED INTO THE POCONOS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE COLD FRONT WILL CONTINUE TO MOVE FARTHER OUT TO SEA ON SUNDAY
NIGHT WITH A ROBUST LOW FORECAST TO DEVELOP ALONG THE BOUNDARY.
THE THE MODEL GUIDANCE CONTINUES TO KEEP THE LOW WELL TO OUR EAST.
THE CIRRUS SHIELD ASSOCIATED WITH THE SYSTEM SHOULD BE OVERHEAD ON
SUNDAY EVENING BEFORE MOVING TO OUR EAST LATE ON SUNDAY NIGHT.
A MID LEVEL SHORT WAVE TROUGH APPROACHING FROM THE WEST IS
FORECAST TO PASS OVERHEAD ON MONDAY MORNING. THE COLDEST AIR OF
THE NEW WEEK IS EXPECTED TO ARRIVE IN ITS WAKE FOR MONDAY.
ANOTHER MID LEVEL SHORT WAVE TROUGH FROM THE NORTHWEST IS
ANTICIPATED TO PASS OVER OUR REGION LATE ON MONDAY NIGHT. THE
FEATURE IS EXPECTED TO BE PRECEDED BY SOME MID LEVEL CLOUDS ON
MONDAY EVENING. IT MAY BE ACCOMPANIED AND FOLLOWED BY SOME
STRATOCUMULUS OVER OUR NORTHERN COUNTIES ON MONDAY NIGHT.
A MID LEVEL RIDGE IS FORECAST TO BUILD OVER THE EASTERN STATES
AND THE WESTERN NORTH ATLANTIC DURING THE BALANCE OF THE NEW WEEK.
SURFACE HIGH PRESSURE IS EXPECTED TO MOVE FROM THE SOUTHEASTERN
STATES ON MONDAY NIGHT TO CANADA`S MARITIME PROVINCES ON
WEDNESDAY. A TRAILING SURFACE RIDGE IS FORECAST TO EXTEND INTO OUR
REGION INTO FRIDAY.
WE ARE ANTICIPATING DRY WEATHER FOR THE COMING WEEK. TEMPERATURES
WILL BEGIN ABOUT 10 DEGREES BELOW NORMAL ON MONDAY BUT THEY SHOULD
REBOUND TO AROUND 6 TO 8 DEGREES ABOVE NORMAL FOR THANKSGIVING DAY
AND FRIDAY.
A COLD FRONT IS EXPECTED TO APPROACH FROM THE NORTHWEST ON FRIDAY
NIGHT AND IT SHOULD PASS THROUGH OUR REGION ON SATURDAY. WE WILL
INDICATE A CHANCE OF RAIN SHOWERS AT THAT TIME.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...MAINLY VFR CONDITIONS ARE EXPECTED TO CONTINUE THIS
EVENING AND OVERNIGHT. A COLD FRONT WILL APPROACH THE REGION FROM
THE WEST THIS EVENING, AND WE WILL SEE A GRADUAL THICKENING AND
LOWERING OF VFR CLOUDS. WINDS THROUGH THIS EVENING WILL BE OUT OF
THE EAST-SOUTHEAST AND MAINLY IN THE 5 TO 8 KNOT RANGE. THE COLD
FRONT IS EXPECTED TO SWEEP ACROSS THE AREA BETWEEN ABOUT 07Z TO
12Z, AND AS THE FRONT PASSES THROUGH, WINDS WILL BECOME MORE
WESTERLY TO WEST-NORTHWEST AND INCREASE SOME UP TOWARD 10 TO 12
KNOTS. IN ADDITION WITH THE PASSAGE OF THE FRONT THROUGH THE
OVERNIGHT TO EARLY MORNING, CEILINGS WILL LOWER TOWARD ABOUT 3500
TO 4000 FEET WITH ISOLATED SHOWERS POSSIBLE, BUT AT THIS TIME, WE
DO NOT EXPECT ANY EXTENDED TIME OF SUB-VFR CONDITIONS. SHOWERS
WERE NOT INCLUDED IN THE TAFS AS THEY WILL BE BRIEF AND ISOLATED
IN NATURE.
SUNDAY...VFR CONDITIONS ARE EXPECTED BEHIND THE COLD FRONT WITH
CLOUDS THINNING. NORTHWESTERLY WINDS WILL BECOME GUSTY FOR MOST
SITES IN THE 12Z TO 14Z TIME FRAME AND CONTINUE THROUGH THE BULK
OF THE DAY. GUSTS INTO THE 20 TO 25 KNOT RANGE ARE EXPECTED.
OUTLOOK...
SUNDAY NIGHT THROUGH WEDNESDAY...MAINLY VFR.
WEDNESDAY NIGHT AND THURSDAY...MAINLY VFR. HOWEVER, PATCHY LATE
NIGHT AND EARLY MORNING FOG IS POSSIBLE.
&&
.MARINE...
A COLD FRONT WILL BE CROSSING THE AREA DURING THE OVERNIGHT TO
EARLY MORNING SUNDAY. AS THE FRONT PASSES, WINDS WILL SHIFT FROM
THE SOUTHEAST TO WESTERLY AND THEN NORTHWESTERLY DURING THE
DAYTIME SUNDAY. IN ADDITION, GUSTS WILL ALSO PICK UP BEHIND THE
FRONT, WITH GUSTS AROUND 25 KNOTS PLUS BEGINNING AROUND DAYBREAK
SUNDAY. SEAS WILL ALSO RESPOND WILL SOME 4 TO 5 FOOT SEAS FOR THE
ATLANTIC COASTAL WATERS AND 2 TO 4 FOOT SEAS INTO DELAWARE BAY. WE
HAVE RAISED A SMALL CRAFT ADVISORY FOR OUR COASTAL WATERS AND
DELAWARE BAY BEGINNING 11Z SUNDAY.
OUTLOOK...
SUNDAY NIGHT...A SMALL CRAFT ADVISORY IS IN EFFECT FOR NORTHWEST
WINDS GUSTING TO 25 TO 30 KNOTS.
MONDAY...THE SMALL CRAFT ADVISORY MAY NEED TO BE EXTENDED IN TIME
AS 25 KNOT WIND GUSTS FROM THE NORTHWEST MAY LINGER INTO AT LEAST
PART OF MONDAY.
MONDAY NIGHT THROUGH THURSDAY...NO MARINE HEADLINES ARE
ANTICIPATED.
&&
.TIDES/COASTAL FLOODING...
A DEVELOPING ONSHORE FLOW ALONG WITH THE HIGH ASTRONOMICAL TIDES
ASSOCIATED WITH THE UPCOMING FULL MOON MAY RESULT IN SOME MINOR
COASTAL FLOODING DURING THE SECOND HALF OF THE WEEK. THE MORNING
HIGH TIDE CYCLES ON THURSDAY AND FRIDAY SEEM MOST SUSCEPTIBLE.
POSITIVE DEPARTURES OF ONLY 0.3 TO 0.6 FEET ARE NEEDED FOR MINOR
FLOODING TO BEGIN.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM SUNDAY TO 6 AM EST MONDAY FOR
ANZ430-431-450>455.
&&
$$
SYNOPSIS...IOVINO
NEAR TERM...KLINE
SHORT TERM...KLINE
LONG TERM...IOVINO
AVIATION...IOVINO/KLINE
MARINE...IOVINO/KLINE
TIDES/COASTAL FLOODING...IOVINO
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
255 PM CST SAT NOV 21 2015
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST SAT NOV 21 2015
20z/2pm surface analysis shows 1006mb low over west-central Ohio,
with light snow lingering westward across much of the KILX CWA. The
snow has ended and skies are beginning to clear west of the Illinois
River, and this clearing will work its way steadily eastward over
the next few hours. Satellite timing tools suggest the back edge of
the cloud shield will be along a Bloomington to Shelbyville line by
00z/6pm...then will be into Indiana by 04z/10pm. Skies will then be
clear across the board until late tonight when SCT-BKN mid-level
clouds associated with a short-wave trough spill into the W/SW CWA
toward dawn. Strong northwesterly winds gusting to between 20 and
30 mph early this evening will diminish to less than 10 mph and back
to the W/SW overnight. Thanks to the clear skies and diminishing
winds over a fresh snow-cover across the northern half of the CWA,
this will be the coldest night thus far this season. Lows will drop
into the teens in most areas, but will bottom out in the single
digits where the snow cover is deepest across Knox, Stark, and
Marshall counties.
&&
.LONG TERM...(Sunday through Saturday)
ISSUED AT 255 PM CST SAT NOV 21 2015
Cold air moving into the region overnight with clearing skies, and
by Sunday morning, temperatures will drop into the single digits and
teens. Brisk winds in the morning will result in wind chills
dropping to -5C to 11C range. Sundays high temperatures will
struggle into the 30s, with areas in the north and nearer to any
remaining snow will have a hard time reaching the freezing mark,
although southerly winds will assist to counter with some weak waa.
Southwesterly flow aloft assists the warm up with the next system
digging into the desert SW and amplifying the pattern across the
CONUS. Big question for the first part of the week will be how much
of the snow remains in the northern tier of the state. Have pulled
down the temps both Monday and Tuesday from the SuperBlend to
compensate for the influence of the snowpack. Elsewhere,
temperatures start on a warming trend that will continue through the
holiday. By Wednesday and Thursday, temps are above freezing through
the overnight as well and the next system lays out a boundary across
the region, providing a focus for plenty of rain in the Midwest in
time for holiday travel. So far the models are keeping rain
prolonged through Thanksgiving and into Friday. Disparity in the
operational models with respect to the timing/clearing out of the
wave. With ECMWF and the Canadian hinting at a kicker wave digging
in over the Pacific, inclined to point the forecast towards a more
rapid clearing. Cold air will move in again behind the system, with
chilly temperatures back for next weekend.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1218 PM CST SAT NOV 21 2015
IFR conditions will prevail at the central Illinois terminals for
the next few hours...before the low clouds/snow begin to clear the
area from west to east by mid to late afternoon. Latest satellite
imagery shows back edge of clouds currently along the Mississippi
River and advancing steadily eastward. Based on satellite timing
tools and HRRR forecasts...have ended the snow at KPIA by
20z...then further east to KCMI by 22z. Skies will clear at KPIA
by 22z...but will remain overcast further east at KCMI until
around 01z. Northwesterly winds will become strong/gusty this
afternoon through early evening. Current obs are already showing
gusts in the 25 to 30kt range and these will continue/spread
eastward through the remainder of the day. As low pressure lifts
further northeastward and the pressure gradient relaxes...the
gusts will subside by mid-evening. As high pressure
approaches...winds will become light and gradually back to the SW
late tonight into Sunday morning.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until 3 PM CST this afternoon for ILZ038-
043>046-055-057.
&&
$$
SHORT TERM...Barnes
LONG TERM...HJS
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1218 PM CST SAT NOV 21 2015
.UPDATE...
ISSUED AT 1043 AM CST SAT NOV 21 2015
16z/10am surface analysis shows 1012mb low between KDEC and KMTO.
Widespread precipitation is ongoing across all of central and
southeast Illinois, with the rain/snow line along/south of a
Taylorville to Robinson line. As the low shifts eastward into
Indiana, northwesterly winds will cool the atmosphere sufficiently
to support a rain/snow mix as far south as Olney/Lawrenceville
this afternoon. Light to moderate snow will continue across the
northern two-thirds of the KILX CWA through early afternoon before
the precip gradually ends from west to east. Latest satellite
imagery shows the back edge of the cloud/precip shield across
eastern Iowa/northern Missouri and this will advance steadily
eastward over the next few hours. Based on satellite timing tools
and HRRR forecast, have lingered PoPs across the E/NE CWA a bit
longer into the afternoon before ending all precip by 00z. Storm
total snowfall with this system is on track with previous
forecasts: however, have increased the amounts into the 6 to
8-inch range across Knox/Stark counties and have included amounts
of 1 inch or less as far south as a Springfield to Mattoon line.
&&
.SHORT TERM...(Today)
ISSUED AT 336 AM CST SAT NOV 21 2015
the 09z/3am surface analysis shows the center of the low pressure in
south-central Missouri, with a warm front extending across southern
IL, roughly along I-70. The rain-snow line has maintained farther
north...with snow remaining north of a line from Macomb to Peoria to
Pontiac. The Peoria airport just SW of Peoria has little to no snow,
while the north side of Peoria has what looks to be at least an inch
of snow, and possibly more, on grassy surfaces based on IDOT
cameras. Reports of 2.5" of snow have come in from Knox county
observers in Altona and Abingdon earlier tonight.
The RAP and HRRR take the surface low across southern IL, with
deformation band snows continuing in our NW counties. Cold air along
the northern edge of the system will gradually get pulled southward
into our counties, prompting the rain to change to snow
progressively farther south and east. Snowfall amounts look on track
for our NW counties to be in the 3 to 6 inch range, with a sharp
cutoff down to an inch or less. As the deformation band progresses
across central IL into the afternoon, our NE counties could see
snowfall amounts up to an inch or possibly a little more toward
Hoopeston. We did not expand the winter weather advisory eastward, as
snow amounts should remain enough below the 3" criteria for
Champaign and Vermilion counties. The southern row of counties of
our advisory (Fulton, Tazewell, McLean) will be borderline in terms
of snow amounts as well, but will continue with headlines unchanged
as there remains some uncertainty as to how soon the cold air will
surge southward to change rain to snow, and how efficient of
snowfall production will occur in our NW areas.
Temps will remain warm enough for rain south of I-72 for a majority
of the day, with any change to snow coming so late in the event
that little to no snow accumulation is expected south of there.
The center of the surface low is forecast to pull into Indiana by 11
am/17z, so cold air will invade on strong NW winds by early
afternoon. High temps will likely occur by Noon in most areas
because of that, with steady or falling temps this afternoon as
winds increase to 25-30 mph. The snow should generally be too wet to
blow around, but wind chills could drop into the teens in our W-NW
counties.
.LONG TERM...(Tonight through Friday)
ISSUED AT 336 AM CST SAT NOV 21 2015
Strong short wave to lift ne of central IL early this evening with
Canadian high pressure over the central Rockies quickly ridging east
into the mid MS river valley by dawn Sunday. Clouds to decrease from
west to east later this afternoon and into the evening while nw
winds 15-25 mph at sunset today diminish to 5-10 mph overnight.
Diminishing clouds and winds to bring a very cold night to the
area especially over northern CWA where snow cover where lows will
be 7- 13F with mid teens over central parts of CWA and upper teens
to near 20F in southeast IL. Wind chills will lower to 5 above to
5 below zero northern cwa and 10-15 southeast IL. This will be the
coldest night since March 6th over central IL. High pressure
ridges into the Ohio river valley by sunset Sunday while upper
level trof axis shifts east of IL. A mostly sunny but cold day
with highs ranging form lower 30s from i-74 ne, mid 30s central
CWA and upper 30s sw CWA. Winds to become ssw at 7-14 mph by
Sunday afternoon.
After a taste of winter weather this weekend for IL, temperatures to
moderate back above normal during the upcoming work week with upper
level heights rising over the region and nearly zonal upper level
flow Monday becoming sw by mid week with strong upper level ridge in
the east and strong upper level low/trof digging in the western
states. Dry weather expected Monday through Wednesday with temps
warming back up. Lows Sunday night in the mid to upper 20s. Highs
Monday range from lower 40s from I-74 ne where remaining snow cover
likely to melt while upper 40s to near 50F sw CWA. Highs by Wed in
the low to mid 50s and mid to upper 50s on Thanksgiving day. 00Z
models have trended slower with qpf returning to IL Wed night and
Thu and looks like a wet period from Wed night into early Sat. GFS
is quicker than ECMWF model with cold front moving through later Thu
night and Friday with highest pops will likely be. Between 1 and 2
inches of rain appear possible during this time frame. Rain chances
diminish next weekend and colder air returns to central/se IL.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1218 PM CST SAT NOV 21 2015
IFR conditions will prevail at the central Illinois terminals for
the next few hours...before the low clouds/snow begin to clear the
area from west to east by mid to late afternoon. Latest satellite
imagery shows back edge of clouds currently along the Mississippi
River and advancing steadily eastward. Based on satellite timing
tools and HRRR forecasts...have ended the snow at KPIA by
20z...then further east to KCMI by 22z. Skies will clear at KPIA
by 22z...but will remain overcast further east at KCMI until
around 01z. Northwesterly winds will become strong/gusty this
afternoon through early evening. Current obs are already showing
gusts in the 25 to 30kt range and these will continue/spread
eastward through the remainder of the day. As low pressure lifts
further northeastward and the pressure gradient relaxes...the
gusts will subside by mid-evening. As high pressure
approaches...winds will become light and gradually back to the SW
late tonight into Sunday morning.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until 3 PM CST this afternoon for ILZ038-
043>046-055-057.
&&
$$
UPDATE...Barnes
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1043 AM CST SAT NOV 21 2015
.UPDATE...
ISSUED AT 1043 AM CST SAT NOV 21 2015
16z/10am surface analysis shows 1012mb low between KDEC and KMTO.
Widespread precipitation is ongoing across all of central and
southeast Illinois, with the rain/snow line along/south of a
Taylorville to Robinson line. As the low shifts eastward into
Indiana, northwesterly winds will cool the atmosphere sufficiently
to support a rain/snow mix as far south as Olney/Lawrenceville
this afternoon. Light to moderate snow will continue across the
northern two-thirds of the KILX CWA through early afternoon before
the precip gradually ends from west to east. Latest satellite
imagery shows the back edge of the cloud/precip shield across
eastern Iowa/northern Missouri and this will advance steadily
eastward over the next few hours. Based on satellite timing tools
and HRRR forecast, have lingered PoPs across the E/NE CWA a bit
longer into the afternoon before ending all precip by 00z. Storm
total snowfall with this system is on track with previous
forecasts: however, have increased the amounts into the 6 to
8-inch range across Knox/Stark counties and have included amounts
of 1 inch or less as far south as a Springfield to Mattoon line.
&&
.SHORT TERM...(Today)
ISSUED AT 336 AM CST SAT NOV 21 2015
the 09z/3am surface analysis shows the center of the low pressure in
south-central Missouri, with a warm front extending across southern
IL, roughly along I-70. The rain-snow line has maintained farther
north...with snow remaining north of a line from Macomb to Peoria to
Pontiac. The Peoria airport just SW of Peoria has little to no snow,
while the north side of Peoria has what looks to be at least an inch
of snow, and possibly more, on grassy surfaces based on IDOT
cameras. Reports of 2.5" of snow have come in from Knox county
observers in Altona and Abingdon earlier tonight.
The RAP and HRRR take the surface low across southern IL, with
deformation band snows continuing in our NW counties. Cold air along
the northern edge of the system will gradually get pulled southward
into our counties, prompting the rain to change to snow
progressively farther south and east. Snowfall amounts look on track
for our NW counties to be in the 3 to 6 inch range, with a sharp
cutoff down to an inch or less. As the deformation band progresses
across central IL into the afternoon, our NE counties could see
snowfall amounts up to an inch or possibly a little more toward
Hoopeston. We did not expand the winter weather advisory eastward, as
snow amounts should remain enough below the 3" criteria for
Champaign and Vermilion counties. The southern row of counties of
our advisory (Fulton, Tazewell, McLean) will be borderline in terms
of snow amounts as well, but will continue with headlines unchanged
as there remains some uncertainty as to how soon the cold air will
surge southward to change rain to snow, and how efficient of
snowfall production will occur in our NW areas.
Temps will remain warm enough for rain south of I-72 for a majority
of the day, with any change to snow coming so late in the event
that little to no snow accumulation is expected south of there.
The center of the surface low is forecast to pull into Indiana by 11
am/17z, so cold air will invade on strong NW winds by early
afternoon. High temps will likely occur by Noon in most areas
because of that, with steady or falling temps this afternoon as
winds increase to 25-30 mph. The snow should generally be too wet to
blow around, but wind chills could drop into the teens in our W-NW
counties.
.LONG TERM...(Tonight through Friday)
ISSUED AT 336 AM CST SAT NOV 21 2015
Strong short wave to lift ne of central IL early this evening with
Canadian high pressure over the central Rockies quickly ridging east
into the mid MS river valley by dawn Sunday. Clouds to decrease from
west to east later this afternoon and into the evening while nw
winds 15-25 mph at sunset today diminish to 5-10 mph overnight.
Diminishing clouds and winds to bring a very cold night to the
area especially over northern CWA where snow cover where lows will
be 7- 13F with mid teens over central parts of CWA and upper teens
to near 20F in southeast IL. Wind chills will lower to 5 above to
5 below zero northern cwa and 10-15 southeast IL. This will be the
coldest night since March 6th over central IL. High pressure
ridges into the Ohio river valley by sunset Sunday while upper
level trof axis shifts east of IL. A mostly sunny but cold day
with highs ranging form lower 30s from i-74 ne, mid 30s central
CWA and upper 30s sw CWA. Winds to become ssw at 7-14 mph by
Sunday afternoon.
After a taste of winter weather this weekend for IL, temperatures to
moderate back above normal during the upcoming work week with upper
level heights rising over the region and nearly zonal upper level
flow Monday becoming sw by mid week with strong upper level ridge in
the east and strong upper level low/trof digging in the western
states. Dry weather expected Monday through Wednesday with temps
warming back up. Lows Sunday night in the mid to upper 20s. Highs
Monday range from lower 40s from I-74 ne where remaining snow cover
likely to melt while upper 40s to near 50F sw CWA. Highs by Wed in
the low to mid 50s and mid to upper 50s on Thanksgiving day. 00Z
models have trended slower with qpf returning to IL Wed night and
Thu and looks like a wet period from Wed night into early Sat. GFS
is quicker than ECMWF model with cold front moving through later Thu
night and Friday with highest pops will likely be. Between 1 and 2
inches of rain appear possible during this time frame. Rain chances
diminish next weekend and colder air returns to central/se IL.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 600 AM CST SAT NOV 21 2015
Conditions are expected to continue at IFR or LIFR for PIA and BMI
where snow will fall through the morning and into early afternoon.
IFR conditions will develop at SPI, DEC and CMI as the morning
progresses, as rain changes to snow. Low pressure will pass south
of the area this morning, roughly just south of I-70. The low will
move into Indiana before Noon/18z, causing winds to shift to the
NE, then N, then NW by afternoon for all TAF sites. Wind speeds
will increase to 15 to 20kt after 15z, with gusts to 30kt at times
this afternoon. Winds will diminish to 8-12kt after 00z.
Initially, surface temps will hover right around or just above
freezing early this morning for a few hours. Ground temperatures
are generally above freezing, so snow accumulation on travel
surfaces will remain lower than grassy areas. 1 inch of slushy
accumulation could occur at PIA, with less than an inch at BMI and
CMI, and little to no snow accumulation at DEC and SPI. IFR
conditions should gradually improve to MVFR during the afternoon
and then to VFR after 00-03z.
&&
.ILX Watches/Warnings/Advisories...
Winter Weather Advisory until noon CST today for ILZ027>031-
036>038.
&&
$$
UPDATE...Barnes
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1012 AM CST SAT NOV 21 2015
.UPDATE...
915 AM CST
ONLY CHANGE TO HEADLINES WAS TO UPGRADE ADVISORY TO A WINTER STORM
WARNING FOR LAKE AND PORTER COUNTIES IN NORTHWEST INDIANA.
MAJORITY OF FORECAST CONTINUES WELL ON TRACK...INCLUDING FOR THE
MOST PART SNOWFALL TOTALS AND ENDING TIMES TODAY.
THE WELL-DEFINED TROUGH ON SATELLITE THIS MORNING IS SWINGING
INTO THE AREA...PIVOTING SLIGHTLY MORE NEGATIVELY TILTED...WITH
RAPID MID-LEVEL AND DYNAMIC COOLING. AN IMPRESSIVE 500MB
TEMPERATURE DIFFERENCE FROM MPX TO DVN OF 16C HIGHLIGHTS THAT.
THE SURFACE TEMPERATURES ARE STARTING TO SLOWLY FALL IN NORTH
CENTRAL ILLINOIS WITH NORTHERLY WINDS. TEMPERATURES ARE ALSO
BEGINNING TO SLOWLY COOL NEAR THE IMMEDIATE LAKE SHORE OF
NORTHEAST ILLINOIS...INCLUDING DOWNTOWN CHICAGO...WHERE RAIN OR
RAIN/SNOW MIX WITH LITTLE TO NO ACCUMULATION HAS BEEN REPORTED
THUS FAR THIS MORNING. EXPECTING TO SEE THESE LOCATIONS TURN OVER
TO ALL SNOW FOR GOOD OVER THE NEXT COUPLE HOURS.
AS DEFORMATION ENVELOPS THE AREA AS NOTED IN THE PREVIOUS
DISCUSSION...WE SHOULD CONTINUE TO SEE HEAVIER SNOW BLOSSOM ON
RADAR WHICH WE HAVE NOTICED UNDULATE SINCE 7 AM. AREAS OF HALF
MILE AND TEMPORARY QUARTER MILE VISIBILITY HAVE BEEN OBSERVED
UNDER THESE. SNOWFLAKE QUALITY...OR SNOW RATIOS...ALSO APPEAR TO
INCREASE IN THESE AREAS BASED ON OUT OUR WINDOW AND A FEW OTHER
REPORTS. THAT WOULD LINE UP WITH SATURATION PROFILES...ESPECIALLY
WHERE THE WINDS ARE LIGHTER IN THE LOW-LEVELS /LESS FLAKE
FRAGMENTING/...SUCH AS NORTHEAST ILLINOIS AND FAR NORTHWEST
INDIANA AT PRESENT. TEMPORARY ONE INCH PER HOUR RATES WILL BE
MOST FAVORED IN THESE AREAS.
LAKE ENHANCEMENT CONTINUES TO BE SEEN NEAR THE WI/IL STATE
LINE...WITH EVEN SOME 40 MPH GUSTS ON THE IMMEDIATE SOUTHEAST
WISCONSIN SHORE LIKELY INDICATING THE PRESENCE OF SHARPENING
CONVERGENCE AND STEEP LAPSE RATES. THIS ENHANCEMENT WILL SLOWLY
MOVE SOUTHWARD THROUGH EARLY AFTERNOON...WITH THE LONGEST
RESIDENCE TIME JUST NORTH OF CHICAGO IT WOULD APPEAR ON THE HRRR
AND RAP PREDICTED WIND FIELDS. THIS WILL SHIFT INTO NORTHWEST
INDIANA DURING THE MID AFTERNOON OR SO AND FURTHER INCREASE RATES
AND TOTAL SNOW. WHILE SNOWFALL TOTALS IN PARTS OF LAKE AND PORTER
ARE LIKELY TO NOT REACH SIX INCHES...THE COMBINATION OF THE
HEAVIER SYNOPTIC AND EXPECTED LATER MESOSCALE RATES DURING THE
DAYTIME...AND THE FIRST EVENT OF THE YEAR...HAVE COLLABORATED THE
UPGRADE TO WARNING FOR THERE.
MTF
&&
.SHORT TERM...
330 AM CST
THROUGH MONDAY...
A VERY IMPRESSIVE DYNAMIC EARLY SEASON STORM SYSTEM HAS ONLY
PRESENTED ITS FIRST PUNCH TO PORTIONS OF THE AREA. YESTERDAY
EVENING...A VERY STRONGLY FRONTOGENTICALLY FORCED HEAVY SNOW BAND
DEVELOPED OVER FAR NORTHERN ILLINOIS AND DROPPED UP TO 10 INCHES
WITHIN A FEW HOURS. HOWEVER...AREAS FARTHER SOUTH RECEIVED LIGHTER
AMOUNTS OUT OF THIS FIRST PERIOD OF SNOW. THIS IS EXPECTED TO
CHANGE THIS MORNING...HOWEVER...AS ADDITIONAL MODERATE TO
OCCASIONALLY HEAVY BANDS OF SNOW DEVELOP OVER THE AREA AND PRESENT
THE OPPORTUNITY FOR AREAS SOUTH OF YESTERDAY EVENINGS HEAVY SNOW
EVENT TO GET SNOW ACCUMULATION.
THE TRACKS OF THE 850 AND 700 MB LOWS APPEAR QUITE FAVORABLE FOR
HEAVY SNOW ACROSS NORTHERN ILLINOIS AND NORTHWESTERN INDIANA TODAY.
STRONG Q-VECTOR CONVERGENCE IS EXPECTED TO SET UP OVER THE REGION
THIS MORNING AS THE MAIN MID LEVEL SHORT WAVE TRANSITIONS TO A
NEGATIVE TILT. THIS SUGGESTS THE PRESENCE OF STRONG LARGE SCALE
FORCING FOR ASCENT...ESPECIALLY CONSIDERING THE AREA WILL RESIDE
WITHIN THE FAVORABLE LEFT EXIT REGION OF A 120+ KT UPPER LEVEL JET.
AS THE LOWER LEVEL LOW SHIFTS EASTWARD OVER ILLINOIS...THIS WILL
RESULT IN A CORRIDOR OF RATHER STOUT DEFORMATION...AND THE RESULTANT
BANDS OF FRONTOGENESIS SHOULD DIVE AN AREA OF MODERATE...TO
OCCASIONALLY HEAVY SNOW OVER THE AREA TODAY. THIS STRONG FORCING FOR
ASCENT ALSO LOOKS TO BE COMPLEMENTED...AT LEAST OVER NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BY FAVORABLE THERMODYNAMICS FOR
LAKE ENHANCEMENT.
SURFACE TEMPERATURES HAVE REMAINED AT...OR A COUPLE OF DEGREES ABOVE
FREEZING THROUGH THE NIGHT IN MOST AREAS OUTSIDE OF NORTH CENTRAL
ILLINOIS...AND THIS HAS RESULTED IN LITTLE SNOW
ACCUMULATION...ESPECIALLY CONSIDERING SNOW RATES HAVE REMAINED
FAIRLY LIGHT OVERNIGHT. SURFACE TEMPERATURES SHOULD BEGIN TO COOL TO
AND BELOW FREEZING DURING THE DAY AS HEAVIER PRECIPITATION RATES
DEVELOP...AND THIS SHOULD ALLOW SNOW TO ACCUMULATE...ESPECIALLY ON
GRASSY AREAS. IT IS A BIT UNCERTAIN HOW MUCH SNOW WILL ACCUMULATE ON
PAVEMENT...DUE TO THE WARMER TEMPERATURES. HOWEVER...AT LEAST SOME
SLUSHY ACCUMS LOOKS POSSIBLE.
AS MENTIONED ABOVE...THERMODYNAMICS SHOULD BECOME INCREASING
FAVORABLE FOR A LAKE ENHANCED BAND OF SNOW TO DEVELOP OVER
NORTHEASTERN ILLINOIS AND EVENTUALLY NORTHWESTERN INDIANA. COOLER
MID-LEVEL TEMPERATURES MOVING OVER THE AREA SHOULD SET UP THESE
FAVORABLE CONDITIONS. HI-RES GUIDANCE IS ACTUALLY PICKING UP ON
THIS...AND SUGGESTS THAT A HEAVY LAKE ENHANCED BAND OF HEAVY SNOW
WILL IMPACT PORTIONS OF NORTHEASTERN ILLINOIS THIS MORNING.
IT APPEARS THAT THE STORM SYSTEM WILL TRACK A BIT FARTHER SOUTH THEN
WHAT WAS ANTICIPATED EARLIER. THEREFORE...IT APPEARS THAT AREAS
OUTSIDE THE CURRENT ADVISORY COULD END UP GETTING A FEW INCHES OF
ACCUMULATION TODAY. BECAUSE OF THIS...WE OPTED TO EXPAND THE WINTER
WX ADVISORY FARTHER SOUTH TO COVER THE REST OF MY AREA. OVERALL...IT
APPEARS THE HEAVIEST SNOW TODAY WILL FALL DURING THE MORNING...THEN
BEGIN TAPERING OFF FROM WEST TO EAST THROUGH THE AFTERNOON. LAKE
ENHANCED SNOW SHOWERS COULD LINGER INTO THE EVENING OVER FAR
NORTHEASTERN PORTER. OTHERWISE...THINGS SHOULD BE DONE IN MOST
AREAS BY LATER THIS AFTERNOON. IT APPEARS THAT AMOUNTS OF 3 TO 7
INCHES COULD FALL ACROSS THE AREA TODAY. THEREFORE...NO CHANGES
ARE PLANED TO THE HEADLINES...ASIDE FROM THE EXPANSION MENTIONED.
NORTH-NORTHWESTERLY WINDS WILL BECOME VERY GUSTY THIS AFTERNOON AS
THE SURFACE LOW TRACKS OVER THE EASTERN GREAT LAKES REGION. THESE
STRONGER WINDS COULD PRODUCE SOME BLOWING SNOW. HOWEVER...DUE TO THE
WETTER NATURE OF THE SNOW...THIS MAY NOT BE TOO BIG OF AN
ISSUE...AND I HAVE OPTED TO LEAVE THE MENTION OUT OF THE FORECAST AT
THIS TIME.
OTHERWISE...EXPECT A VERY COLD NIGHT TONIGHT WITH THE FRESH SNOW ON
THE GROUND. AREAS ACROSS NORTH CENTRAL ILLINOIS LOOK TO DROP INTO
THE SINGLE DIGITS...WITH TEENS LIKELY IN MOST OTHER AREAS.
SUBFREEZING TEMPERATURES WILL CONTINUE SUNDAY...BEFORE TEMPERATURES
BEGIN TO INCH ABOVE FREEZING ON MONDAY.
KJB
&&
.LONG TERM...
238 AM CST
TUESDAY THROUGH FRIDAY...
THE EXTENDED BEGINS QUIETLY WITH HIGH PRESSURE SHIFTING FROM THE
SOUTHEAST U.S. TO NEW ENGLAND BY WEDNESDAY MORNING. WINDS TURN
SOUTH WEDNESDAY USHERING IN WARMER AIR. THIS IS REFLECTED IN HIGH
TEMPS WHICH WILL JUMP FROM THE UPPER 30S TO MID 40S TUESDAY TO THE
LOW TO MID 50S THURSDAY. A WEAKENING MID LEVEL SHORTWAVE TROUGH
PASSES OVER THE REGION WEDNESDAY BRINGING A SLIGHT CHANCE TO CHANCE
OF LIGHT RAIN WITH IT. HAVE MORE CONFIDENCE IN RAIN WEDNESDAY NIGHT
THAN WEDNESDAY AS THE NEXT LOW/S WARM FRONT LIFTS NORTH OVER THE
REGION...BUT ONLY EXPECTING LIGHT RAIN. THE LOW ARRIVES OVER IOWA
THURSDAY MORNING AND CONTINUES NORTHEAST THROUGH LATE IN THE WEEK.
THE GFS IS MORE AGGRESSIVE WITH THE RAIN/S PROGRESSION THURSDAY.
THINKING AREAS WEST OF I-55 WILL LIKELY SEE RAIN WHILE THE GFS
SUGGESTS THE WHOLE WARNING AREA WILL RECEIVE RAIN. GUSTY SOUTH
WINDS ARE ALSO EXPECTED THURSDAY WITH GUSTS UP TO 30 MPH. THE LOW/S
COLD FRONT SWINGS THROUGH FRIDAY LEADING TO COOLER TEMPS...AN END TO
THE RAIN...AND NORTHWEST TO WEST WINDS. HIGH TEMPS FRIDAY WILL STILL
BE AROUND TO SLIGHTLY ABOVE AVERAGE RANGING FROM THE MID 40S TO
AROUND 50.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* ONGOING SNOW THROUGH THE EARLY AFTERNOON. VSBYS WILL DROP AGAIN
TO NEAR 1/2SM WITH A LAKE EFFECT BAND FROM 17-202Z.
* IFR TO LIFR CIGS IMPROVING IN THE AFTERNOON.
* NORTHEAST WINDS ARE SHIFTING NORTHERLY CURRENTLY. ANOTHER SHIFT TO
NNW AND GUST TO 20-25KT EXPECTED THIS AFTN.
MM
//DISCUSSION...UPDATED 12Z...
SNOW WILL INCREASE THIS MORNING WITH 3/4 SM VSBY EXPECTED AT ALL
OF THE TAF SITES. PERIODS OF 1/4 SM VSBY ARE NOT OUT OF THE
QUESTION ACROSS THE EASTERN TERMINALS. A LAKE EFFECT BAND WILL
FORM LATE THIS MORNING AND ROTATE OVER THE EASTERN TERMINALS.
1/4SM WITH HEAVY SNOW IS EXPECTED UNDER THIS BAND ALONG WITH QUICK
ACCUMULATIONS. HOWEVER THE BAND WILL BE TRANSIENT SO THE HEAVY
SNOW WILL LAST ABOUT AN HOUR OR LESS. RFD WILL NOT BE AFFECTED BY
THE BAND AND WILL SEE THE SNOW END FIRST AROUND NOON. EAST WINDS
WILL BE LESS THAN 10 KT EARLY THIS MORNING AND INCREASE TO CLOSE
TO 10 KT LATE THIS MORNING. WINDS WILL BE BACKING LATE THIS
MORNING AND BECOME NORTHWEST GUSTING TO 20-25 KT EARLY THIS AFTN.
FLURRIES OR LIGHT SNOW MAY PERSIST PAST 19Z AT THE EASTERN
TERMINALS...BUT NOT EXPECTING ANY SIGNIFICANT IMPACT FROM THE
LINGERING SNOW.
LIFR CIGS WILL LIFT AFTER THE SNOW TO MVFR AND CLEAR OUT THIS
EVENING WITH WINDS BECOMING SOUTHWEST SUNDAY MORNING.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH ON SNOW VSBYS THE NEXT 2 HOURS...MEDIUM HIGH CONFIDENCE IN
A LAKE EFFECT BAND DEVELOPING...BUT MEDIUM ON TIMING AND LOWESTY
VSBYS.
* HIGH ON CIG TRENDS.
* MEDIUM ON WIND TRENDS.
MM
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...VFR. SOUTHWEST WINDS.
MONDAY...VFR. WEST WINDS.
TUESDAY...VFR. SOUTH WINDS.
WEDNESDAY...SCHC-CHC -RA. SOUTH WINDS.
THURSDAY...RA LIKELY. MVFR PSBL. GUSTY SOUTH WINDS BECOMING WEST.
FRIDAY...CHC RAIN. IMPROVING TO VFR. NORTHWEST WINDS.
JEE
&&
.MARINE...
238 AM CST
NO CHANGES TO CURRENT SMALL CRAFT ADVISORY AND GALE WARNING. WILL
LIKELY NEED ANOTHER GALE HEADLINE FOR THE SOUTHERN HALF OF THE LAKE
SUNDAY EVENING AND NIGHT...BUT WILL HOLD OFF ON ISSUING ONE NOW
GIVEN THE CURRENT HEADLINES.
WINDS WILL BECOME NORTH TO NORTHWEST ACROSS THE LAKE THIS AFTERNOON
AS THE LOW PRESSURE SYSTEM CURRENTLY OVER TEXAS MOVES OVER THE OHIO
RIVER VALLEY. NW WINDS WILL INCREASE TO GALE FORCE ACROSS THE
SOUTHERN HALF OF THE LAKE AND INDIANA NEARSHORE ZONES. WINDS
DIMINISH OVERNIGHT AS THE LOW MOVES OVER QUEBEC. HIGH PRESSURE
SPREADS OVER THE SOUTHERN MISSISSIPPI VALLEY AND SOUTHEAST U.S. AS
ANOTHER LOW SHIFTS SOUTHEAST OVER ONTARIO SUNDAY NIGHT INTO MONDAY.
WINDS BACK TO SOUTHWEST AND GALES ARE EXPECTED SUNDAY NIGHT ACROSS
THE SOUTHERN HALF OF THE LAKE. WINDS DIMINISH AND BECOME WEST BEHIND
THE LOWS COLD FRONT MONDAY. WINDS BACK TO SOUTH AHEAD OF THE NEXT
LOW TUESDAY AND INCREASE TO 15-25 KT WEDNESDAY. THE LOW IS PROGGED
TO PASS JUST NORTHWEST AND NORTH OF THE LAKE THURSDAY NIGHT INTO
FRIDAY WITH SOUTH WINDS INCREASING TO AT LEAST 30 KT THURSDAY
BECOMING WEST 20-25 KT BEHIND THE LOW. SOME GUIDANCE MEMBERS DO
SUGGEST WE COULD HAVE GALES THURSDAY.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ022 UNTIL 3 PM
SATURDAY.
WINTER WEATHER ADVISORY...ILZ021-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 3 PM SATURDAY.
IN...WINTER STORM WARNING...INZ001-INZ002 UNTIL 6 PM SATURDAY.
WINTER WEATHER ADVISORY...INZ010-INZ011-INZ019 UNTIL 6 PM
SATURDAY.
LM...GALE WARNING...ILLINOIS NEARSHORE WATERS UNTIL 9 PM SATURDAY.
SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...9 PM SATURDAY TO 9
AM SUNDAY.
GALE WARNING...LMZ743-LMZ744-LMZ745-LMZ777-LMZ779...3 PM
SATURDAY TO 3 AM SUNDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 3 PM SATURDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1238 PM EST SAT NOV 21 2015
.SYNOPSIS...
HIGH PRESSURE WILL CREST OVER THE REGION TODAY. LOW PRESSURE WILL
MOVE NORTHWEST OF THE AREA ON SUNDAY WITH SOME RAIN. A SECOND
AREA OF LOW PRESSURE WILL LIFT ACROSS THE GULF OF MAINE SUNDAY
NIGHT AND THEN INTO THE MARITIMES ON MONDAY WITH MUCH COLDER AIR.
&&
.NEAR TERM /THROUGH TONIGHT/...
1240 PM UPDATE...
SKIES ARE GRADUALLY CLOUDING UP ACRS THE NORTH THIS AFTN AS
EXPECTED. MOSUNNY SKIES THIS MRNG ALLOWED TEMPS TO CLIMB ABV 40F
AT MOST LOCALES ACRS THE NORTH AS OF 17Z THUS HV BUMPED MAXES UP
ABOUT 2 DEGREES FOR TDA. NO OTHER CHGS NEEDED WITH THIS UPDATE.
PREV DISCUSSION BLO...
HIGH PRESSURE WILL BUILD IN FROM THE WEST THIS MORNING WITH
CLEARING EARLY TODAY. THE HIGH PRESSURE SYSTEM WILL CREST OVER THE
REGION TODAY THEN MOVE OFF TO THE EAST THIS EVENING. WEAK LOW
PRESSURE WILL DEVELOP OVER THE GULF OF MAINE BEHIND THE DEPARTING
LOW AND SPREAD RAIN AND SNOW INTO NEW BRUNSWICK TONIGHT. INTENSE
LOW PRESSURE WILL MOVE INTO THE GREAT LAKES TONIGHT THEN MOVE INTO
SOUTHEASTERN QUEBEC PROVINCE EARLY SUNDAY.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
AN INTERESTING SETUP FOR SUNDAY NIGHT INTO EARLY MONDAY.
A FRONTAL SYSTEM IS FORECAST TO SLIDE ACROSS THE AREA ON SUNDAY
W/SOME SHOWERS OR LIGHT RAIN PULLING OUT OF THE AREA IN THE
MORNING. THE 2ND BATCH OF PRECIP IN THE FORM OF RAIN IS EXPECTED
TO SET UP LATER IN DAY AS LOW PRES DEVELOPS OFF THE SOUTHERN NEW
ENGLAND COAST AND LIFTS NNE. THE AREAS THAT WILL SEE MEASURABLE
QPF WILL BE ACROSS THE EASTERN 1/2 OF THE CWA WHERE THE BEST
FORCING AND LLVL CONVERGENCE WILL BE LOCATED. AS THE LOW LIFTS TO
NNE AND THE UPPER TROF DIGS SOME AS IT SWINGS INTO THE NE, COLDER
AIR WILL START TO FILTER INTO THE REGION. THE ECMWF AND GFS ARE IN
AGREEMENT W/THE COLDER AIR COMING IN BY THE EVENING WHILE THE
CANADIAN GEM & NAM HOLD THE COLDER AIR BACK BY 3-6 HRS. DECIDED TO
GO W/A CONSENSUS BLEND OF THE GUIDANCE FOR THIS PACKAGE SHOWING
RAIN GOING OVER TO A PERIOD OF SNOW BY 11 PM OR SO. ALL THE
GUIDANCE IS IN AGREEMENT THAT THE BULK OF THE QPF WILL BE ACROSS
THE EASTERN 3RD OF THE CWA SAY FROM FROM HOULTON DOWN INTO HANCOCK
AND WASHINGTON COUNTY W/UP AROUND 0.50 INCHES. ATTM, IF THERE IS
TO BE ANY SNOWFALL ACCUMULATION, IT WILL BE ACROSS EASTERN
WASHINGTON COUNTY W/A SLUSHY INCH POSSIBLE BEFORE THINGS WIND DOWN
MONDAY MORNING. TEMPERATURES ARE FORECAST TO DROP DOWN INTO THE
LOWER 30S ACROSS EASTERN AREAS AFTER MIDNIGHT W/MID AND UPPER 20S
BACK ACROSS THE W AND NW AREAS.
THE LOW IS FORECAST TO QUICKLY LIFT ACROSS THE MARITIMES ON MONDAY
W/CAA POURING INTO THE REGION AND DRIER CONDITIONS. THERE IS SOME
CONCERN THE CLOUDS ACROSS NORTHERN AND EASTERN MAINE MIGHT HANG ON
THROUGH MONDAY W/A NNW FLOW COMING IN OFF THE OPEN ST. LAWRENCE.
THE GFS SOUNDINGS HINT AT THIS TO BE POSSIBLE W/SOME MOISTURE
SHOWING UP BELOW 3000 FT. THIS SETUP SIMILAR TO THIS SCENARIO TOOK
PLACE LAST WEEK WHEN A CLOUD DECK BELOW 2500 FT HUNG ON LONGER
THAN ANTICIPATED. TEMPERATURES ON MONDAY WILL BE HELD DOWN INTO
THE 30S W/CLOUDS AND A NNW WIND OF 10 TO 20 MPH.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A NNW WIND AND CLOUDS LOOK TO HANG ON ESPECIALLY FOR NORTHERN AND
EASTERN AREAS MONDAY NIGHT W/CAA CONTINUING TO POUR INTO THE
REGION. ANOTHER ITEM TO BE AWARE OF WILL BE POTENTIAL FOR STREAMERS
OF LIGHT SNOW FROM THE OPEN ST. LAWRENCE FOR PORTIONS OF NORTHERN
AND EASTERN MAINE. THE MODEL GUIDANCE TENDS TO HAVE A DIFFICULT
TIME IN PICKING UP THIS MESO-SCALE FEATURE. THE HRRR MODEL AND
NAM12 TEND TO CATCH ON AS WE CLOSE IN CLOSER TO THE EVENT.
CONTINUED BREEZY AND COLD ON TUESDAY W/SOME PARTIAL CLEARING
ACROSS NORTHERN MAINE AS HIGH PRES STARTS TO MOVE IN FROM THE W.
DOWNEAST AND THE COAST SHOULD SEE A DECENT AMOUNT OF SUNSHINE.
DAYTIME TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL FOR LATE
NOVEMBER.
STRONG HIGH PRES IS FORECAST TO BUILD ACROSS THE REGION TUESDAY
NIGHT INTO WEDNESDAY AND THEN LIFT TO THE NE INTO THE NW ATLC ON
THANKSGIVING DAY. THIS WILL MEAN DRY TRAVEL WEATHER FOR THE
THANKSGIVING HOLIDAY W/MODERATING TEMPERATURES.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
NEAR TERM: VFR CONDITIONS THROUGH 06Z TONIGHT THEN CIGS LOWERING
TO MVFR RESTRICTIONS AFTER THIS TIME. IFR EXPECTED AT FVE, HUL AND
BHB WITH LOW MVFR EXPECTED AT CAR, PQI AND BGR BUT CANNOT RULE OUT
THESE TERMINALS WILL DROP TO IFR AT SOME POINT TONIGHT. CONFIDENCE
IS LOW SO HAVE NOT INCLUDED IN TAFS.
SHORT TERM: IFR/MVFR CONDITIONS FOR SUNDAY W/IFR MAINLY FROM KHUL
TO KBHB. MVFR FOR THE REMAINDER OF THE TAF SITES THROUGH SUNDAY
EVENING. CONDITIONS EXPECTED TO IMPROVE TO VFR FOR KBGR AND KBHB
FRO MONDAY WHILE THE NORTHERN TAF SITES COULD SEE PERIODS OF MVFR
CIGS. ATTM, VFR EXPECTED FOR ALL TAF SITES FOR TUESDAY INTO
WEDNESDAY
&&
.MARINE...
NEAR TERM: FOR SUSTAINED WINDS HAVE USED THE NAM12. FOR WAVES:
BUOY OBSERVATIONS INDICATE LONG PERIOD INCOMING SWELL STILL
PRESENT FROM SOUTHEASTERLY FETCH EARLY FRIDAY. EXPECT THIS TO
SUBSIDE RAPIDLY EARLY TODAY WITH OFF-SHORE WIND WAVE BECOMING THE
PREDOMINATE WAVE SYSTEM. SEAS WILL SUBSIDE RAPIDLY TONIGHT ALONG
WITH WINDS WITH LONG PERIOD SOUTHEASTERLY WAVE SYSTEM 1-2 FEET/8
SECONDS ONCE AGAIN BECOMING PREDOMINATE.
SHORT TERM: LOOKING FOR THE POTENTIAL FOR SCA CONDITIONS TO
DEVELOP SUNDAY NIGHT INTO MONDAY ESPECIALLY FOR THE OUTER ZONES.
WINDS ARE EXPECTED TO INCREASE TO 15 TO 20 KT W/GUSTS OF 25 KTS
AND A SWELL GENERATION TAKING PLACE ALLOWING FOR SEAS TO BUILD TO
5 TO 7 FT. AS A MATTER OF FACT, SCA CONDITIONS COULD HANG ON RIGHT
INTO MONDAY AS THE PRES GRADIENT TIGHTENS BETWEEN THE LOW PASSING
ACROSS THE MARITIMES AND STRONG HIGH PRES MOVING IN FROM THE W.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...FARRAR/MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...FARRAR/MIGNONE/HEWITT
MARINE...FARRAR/MIGNONE/HEWITT
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1154 AM CST SAT NOV 21 2015
.SHORT TERM: (Through Tonight)
Issued at 255 AM CST Sat Nov 21 2015
Ongoing precipitation will continue through early afternoon,
eventually tapering off from west to east due to strong
subsidence behind a cold front. A few snowflakes could mix in
with the rain at times almost anywhere across the CWA, especially
just as the rain is ending because that is when the colder air
will also be arriving. However, only the far northern CWA appears
to stay cold enough for long enough to see any accumulation, and
likely only a dusting at best.
Strong CAA behind the aforementioned cold front will produce
falling temperatures during the day across most of the area. The
exception may be across the far eastern CWA where temperatures
could remain steady or perhaps rise by a degree or two before the
front arrives.
Very windy conditions are expected today, especially for the
first few hours after fropa. A tight pressure gradient will lead
to sustained winds of 15-25 mph, and stronger winds aloft will mix
down and produce gusts of 30-40 mph. These values are consistent
with upstream METARs early this morning. BUFKIT soundings from
the RAP and the NAM do suggest that the wind gusts could even be
a bit higher than currently forecast, which would approach
criteria for a wind advisory. However, it does not appear that
wind gusts of that magnitude will be widespread enough to warrant
issuing a wind advisory, therefore no wind headlines are planned
attm. The next shift may revisit the need for wind headlines based
on observational trends. Winds should diminish quickly this
evening.
The coldest temperatures of the season so far are expected
tonight and early tomorrow morning. Overnight lows will likely
drop into the upper teens to lower 20s across the area. Overnight
temperatures would be even lower if it weren`t for the expected
mid/high clouds ahead of a secondary vort max dropping through the
upper trough tonight. These clouds will interfere with radiational
cooling processes.
Kanofsky
.LONG TERM: (Sunday through Friday)
Issued at 255 AM CST Sat Nov 21 2015
A surface high pressure center will be located south of the area
this weekend, keeping winds from the west or west-southwest until
the surface ridge moves farther eastward during the early or
middle part of the week. At that point, winds will likely become
southerly ahead of a developing low pressure system, bringing
warmer air back into the region. Unlike the 00z runs on the last
two days, the current ECMWF/GFS/GEM 00z model runs are in
remarkably good agreement on large scale atmospheric features
through 00z Wed. The primary features of interest are a large,
complex low pressure system over NV/UT and broad southwesterly
flow aloft over MO/IL. Model solutions quickly diverge thereafter,
and confidence in the forecast beyond Tuesday is low.
Kanofsky
&&
.AVIATION: (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1150 AM CST Sat Nov 21 2015
Rapidly moving low pressure system has moved to Indiana taking the
precipitaton with it. Clouds will quickly scatter and clear this
afternoon. Northwest wind will also calm down going light and
variable tonight. High pressure moves east of the area Sunday
bringig a light south wind.
Specifics for KSTL: MVFR clouds looks to scatter and clear around
22z. Clear overnight with wind becoming light and variable after
06z as high pressure moves in. The high quickly moves east Sunday
bringing a light south to southwest wind. An upper level
distubance will bring in some mid clouds overnight.
JPK
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1249 PM EST SAT NOV 21 2015
.SYNOPSIS...
LOW PRESSURE WILL LIFT NORTHEAST ACROSS THE GREAT LAKES TODAY
WITH A TRAILING COLD FRONT SWEEPING EAST ACROSS THE REGION THIS
AFTERNOON. RAIN SHOWERS WILL CHANGE TO SNOW SHOWERS OR FLURRIES
BEFORE ENDING TONIGHT. MUCH COLDER AIR WILL SETTLE IN BEHIND THE
FRONT FOR THE END OF THE WEEKEND. A WARMING TREND WILL THEN RETURN
BY THE FIRST OF THE WEEK INTO THE THANKSGIVING HOLIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY MINOR CHANGES TO GRIDS THIS MORNING AS SURFACE LOW STILL
REMAINS ON TRACK TO BE AROUND KDAY AT 18Z. CURRENT SURFACE
ANALYSIS FROM THIS MORNING SHOWS THE SURFACE LOW CURRENTLY IN
SOUTHERN ILLINOIS WITH A COLD FRONT TRAILING OFF TO THE
SOUTHEAST. THERE WAS ALSO A WEAK WARM FRONT ACROSS NORTHERN
KENTUCKY. DEWPOINTS NORTH OF THE COLD FRONT WERE MAINLY AROUND 20
DEGREES WHILE SOUTH OF THE WARM FRONT AT OR ABOVE 30 DEGREES. KILN
12Z SOUNDING ALSO SHOWS A GOOD DEAL OF DRY AIR BETWEEN 700 AND
1000 MB. FORECAST SOUNDINGS SHOW THE LAYER SLOWLY SATURATING WITH
WEAK WET BULBING FIGHTING WAA AS THE WARM FRONT PUSHES NORTH.
LOOKING AT RAP CRITICAL THICKNESSES IT SEEMS LIKE MOST OF THE
AREA WILL INITIALLY BE RAIN EXCEPT FOR THE POSSIBILITY OF OUR FAR
NORTHERN COUNTIES (DEPENDING ON THE EXACT TRACK OF THE SURFACE LOW
AND WARM FRONT). AS THE FRONT PASSES THERE WILL BE A BRIEF PERIOD
OF RAIN CHANGING OVER TO A RAIN/SNOW MIX AND THEN SNOW. DRIER MID
LEVEL AIR WILL THEN QUICKLY MOVE IN BEHIND THE FRONT. FORECAST
SOUNDINGS STILL SHOW LOW LEVEL SATURATION WHICH WOULD SUPPORT
FLURRIES BEHIND THE FRONT. WIND GUSTS UP TO 35 MPH CAN ALSO BE
EXPECTED ALONG AND BEHIND THE FRONT.
PREV DISCUSSION ->
MID LEVEL ENERGY DROPPING SE INTO THE PLAINS WILL ACT TO SHARPEN
UP AND CARVE OUT A TROF OVER THE NATIONS MID SECTION. AN EMBEDDED
S/W TO ROTATE AROUND THE EAST SIDE OF THIS LONG WAVE TROF THRU THE
MID MS VLY THIS MORNING AND INTO THE GREAT LAKES BY EVENING.
ASSOCIATED SFC LOW OVER THE MID MS VLY TO EJECT NE INTO SW OHIO BY
18Z AND THEN INTO THE EASTERN GREAT LAKES BY EVENING. NUMERICAL
MODEL SOLNS HAVE CLUSTERED COMING INTO BETTER AGREEMENT WITH SFC
LOW NEAR JUST WEST OF DAYTON AT 18Z. COMPARED TO THE 12Z
RUNS...THESE SOLNS HAVE GENERALLY TRENDED FURTHER SOUTH CLOSER TO
THE CONSISTENT ECMWF...ALLOWING FOR A QUICKER CHANGE OVER AND A
LTL MORE SNOW. WILL ALLOW PCPN TO DEVELOP BY AFTN ACROSS THE
WESTERN COUNTIES AND SPREAD EAST. STRONG CAA DEVELOPS WITH 8H
TEMPS GOING FROM AT OR ABOVE 5 DEG C TO -6 DEG C IN THE WEST BY
00Z. WILL BUMP UP SNOW TO AROUND 1 INCH ACROSS THE FAR NW TO ABOUT
ONE TENTH OF AN INCH ON GRASSY AREAS AT ILN. WILL SHOW NON-
DIURNAL TEMPERATURE TREND WITH READINGS FALLING INTO THE 30S IN
THE WEST LATE IN THE DAY. EXPECT WEST WIND GUSTS UP TO 35 MPH WITH
THE FRONTAL PASSAGE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
STRONG SFC COLD FRONT EXPECTED TO PUSH THRU ILN/S EASTERN COUNTIES
DURG THE EARLY EVENING. STRONG CAA TO DEVELOP WITH 8H TEMPS TO
BETWEEN -8 AND -11 DEG C BY SUNDAY MORNING. EXPECT PCPN TO MIX
WITH AND CHANGE TO SNOW ACRS THE ENTIRE FA EARLY TONIGHT. BASED ON
BETTER AGREEMENT OF SOLNS MORE IN LINE WITH COLDER FURTHER SOUTH
ECMWF SOLN...HAVE INCREASED SNOW TO AROUND 1 INCH ACRS THE FAR NW
TO A TENTH OF AN INCH AT ILN. FURTHER SOUTH...EXPECT LITTLE OR NO
ACCUMULATION. EXPECT PCPN TO END OR DIMINISH TO FLURRIES BY LATE
EVENING. AS SFC LOW LIFTS NE INTO SE CANADA...EXPECT DRY SLOW TO
PUSH INTO SW OHIO. WILL ALLOW CLOUDS TO DECREASE ACRS THE WEST
LATE. THE COLDEST AIR OF THE SEASON WILL SETTLE INTO THE OHIO
VALLEY AS SFC HIGH PRESSURE BUILD INTO THE OHIO VALLEY SUNDAY.
EXPECT SAT NIGHTS LOWS TO RANGE FROM THE UPPER TEENS FAR NW TO THE
UPPER 20S SE. SUNDAY WILL OFFER COLD TEMPERATURES WITH A GOOD
AMOUNT OF SUNSHINE. EXPECT SUNDAYS HIGHS TO RANGE FROM THE UPPER
20S NW TO THE MID/UPR 30S SE. TEMPERATURES WILL MODERATE ON THE
BACK SIDE OF THE HIGH MONDAY WITH READINGS FROM NEAR 40 NW TO THE
MID 40S SE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
UPPER LEVEL TROUGH WILL CROSS THE NORTHERN OHIO VALLEY EARLY MONDAY
AND INCREASE CLOUD COVER HERE WITH GENERALLY SUNNY SKIES TO THE
SOUTH. THE AXIS OF THE SURFACE HIGH WILL PASS EAST OF THE REGION
OVERNIGHT MONDAY AND RETURN FLOW WILL PERMIT A WARMING TREND FOR
NEXT WEEK.
MODELS DIVERGE SIGNIFICANTLY ON THURSDAY NIGHT AS A LONGWAVE TROUGH
RUNS FROM JAMES BAY CANADA TO CALIFORNIA AND A SURFACE FRONT LAYS
OUT FROM TX TO SOUTH OF HUDSON BAY. GFS IS PROGRESSIVE WITH THE
UPPER LOW AND PULLS THE SURFACE LOW INTO CANADA...SWEEPING THE FRONT
THROUGH THE OHIO VALLEY LATER FRIDAY AND OVERNIGHT. THE EUROPEAN
DISJOINTS THE UPPER SYSTEM AND CUTS OFF A H5 CLOSED LOW IN THE GREAT
BASIN WITH A SOMEWHAT PROGRESSIVE NORTHERN S/W PEELING OFF OF THIS
AND CROSSING THE GREAT LAKES OVERNIGHT FRIDAY. THIS KEEPS THE
SURFACE FRONT OVER THE MIDWEST AND PULLS ENERGY NORTHEAST AND AWAY
FROM THE OHIO VALLEY FOR FRIDAY AND OVERNIGHT.
BLENDED THE TWO BUT KEPT FORECAST AREA IN LOW CHANCE POPS ON
FRIDAY...INCREASING THEM BEYOND VALID FORECAST PERIOD.
FORECAST UNCERTAINTY ON FRIDAY IS HIGH AFTER THURSDAY NIGHT DUE TO
THESE DIFFERENCES IN MODELS. TEMPS AT THE END OF THE WEEK SHOULD
RISE INTO AT LEAST THE 50S AND COULD PULL INTO THE 60S IF THE DRIER
EUROPEAN VERIFIES. CLOUDY AND RAINY GFS VERIFICATION WILL LIMIT
HIGHS THIS DAY. TOOK A MIDDLE OF THE ROAD APPROACH BEING THIS FAR
OUT.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
SURFACE LOW PRESSURE CURRENTLY LOCATED JUST EAST OF KIND AT THIS
HOUR WITH SNOW BEING REPORTED NEAR THE LOW WITH MOSTLY RAIN BEING
REPORTED SOUTH OF THE LOW. THE LOW WILL CONTINUE TO TRACK OFF TO
THE ENE AND BE APPROACHING DAYTON IN THE NEXT COUPLE OF HOURS. AS
PRECIP MOVES INTO THE AREA WIDESPREAD MVFR CIGS CAN BE EXPECTED
WITH POCKETS OF IFR IN THE HEAVIER SHOWERS. A SURFACE COLD FRONT
WILL THEN PUSH THROUGH THE AREA BRINGING GUSTY WINDS ACROSS THE
TAF SITES. 850 MB WINDS ARE SHOWING AROUND 35 KTS (VIA GFS/ RAP)
AND WITH STRONG COLD AIR ADVECTION SOME OF THIS SHOULD BE ABLE TO
MIX DOWN. THERE WILL ALSO BE A SLIGHT WINDOW OF WHEN RAIN WILL START
TO MIX WITH SNOW. IN GENERAL AM NOT IMPRESSED WITH THE CHANCES OF
THIS THOUGH (ESP SOUTHERN TAF SITES) AS FORECAST SOUNDINGS QUICKLY
DRY OUT THE MID LEVELS. A LACK OF MOISTURE IN THE SNOW GROWTH
REGION WOULD FAVOR FLURRIES. TOMORROW AFTERNOON SURFACE HIGH
PRESSURE WILL MOVE INTO THE AREA ALLOWING THE AREA TO SLOWLY CLEAR
AND WINDS TO RELAX.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HAINES/AR
NEAR TERM...HAINES/AR
SHORT TERM...AR
LONG TERM...FRANKS
AVIATION...HAINES
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
518 PM EST SAT NOV 21 2015
.SYNOPSIS...
A FAST MOVING AREA OF LOW PRESSURE WILL RACE DOWN THE ST LAWRENCE
RIVER VALLEY TONIGHT AND SUNDAY...PUSHING A COLD FRONT ACROSS THE
REGION OVERNIGHT. A WEAK CLIPPER LOW WILL MOVE THROUGH NEW YORK
STATE MONDAY NIGHT...FOLLOWED BY A RIDGE OF HIGH PRESSURE THAT
WILL BUILD OVER THE OHIO VALLEY AND EASTERN US TUESDAY THROUGH
THANKSGIVING DAY. A NEW FRONTAL SYSTEM COULD BRING A RETURN OF
RAIN SHOWERS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
A BRIGHT DAY IS IN PROGRESS OVER MOST OF THE THE REGION AS THE
THICKER FRONTAL CLOUDS REMAIN OVER NWRN PA FOR THE TIME BEING.
RIDGE OF HIGH PRESSURE JUST TO OUR EAST WILL ENSURE DRY
CONDITIONS CONTINUING THROUGH THE DAYLIGHT HOURS. WE`LL SEE SERLY
WINDS MAINLY IN THE 10-20 MPH RANGE...WITH HIGHER GUSTS OF 20-25
MPH SUPPORTED OVER THE HIGHER ELEVATIONS.
THE COLD FRONT SHOULD BE ENTERING THE WESTERN STRIPE OF MY CWA
SHORTLY AFTER MIDNIGHT...AND BE EAST OF THE AREA BY SUNRISE. HRRR
TIMING SHOWS THE LEADING RAIN SHOWERS MOVING INTO THE AREA BETWEEN
ABOUT 10 PM AND MIDNIGHT...WITH COLD AIR CHANGING THE PRECIP TO
SNOW SHOWERS BETWEEN ABOUT MIDNIGHT AND 3 AM AS THE FRONT SWEEPS
EAST. THE BEST CHANCE FOR MEASURABLE PRECIP WILL BE OVER THE
WESTERN AND NORTHERN HIGH TERRAIN WITH SHORT RANGE GUIDANCE ALL
AGREEING IN SHOWING THE PRECIP SHIELD DIMINISHING IN COVERAGE AS
IT ENTERS CENTRAL AND EASTERN PA. OVER THESE CENTRAL AND EASTERN
AREAS VERY LIGHT RAIN SHOWERS WILL TAPER OFF AS LIGHT SNOW SHOWERS
OR FLURRIES VERY LATE TONIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
SUNDAY WILL TURN MARKEDLY COLDER AND BREEZY.
THE COLD AIR...WARM LAKES AND MEAN SFC-800MB 250-270 DEG WINDS
INDICATE A POTENTIAL FOR SINGLE LAKE ERIE SNOW BAND INITIALLY
ALONG THE I-90 CORRIDOR LATER TONIGHT AND SUNDAY MORNING...
TRANSITIONING INTO A MORE MULTI-BAND SETUP DURING THE DAY SUNDAY
INTO SUNDAY NIGHT. AT THIS TIME...LATEST OPERATIONAL MODELS AND
THE SREF IS SUGGESTING 2-4 INCHES OF SNOW POSSIBLE NEAR THE NY
BORDER WITH WARREN COUNTY...BUT BEST SNOW IS LIKELY JUST TO THE
NORTH OF THE PA/NY BORDER.
WE WILL CONTINUE OUR LES WATCH FOR NW WARREN COUNTY AT THIS TIME
WITH THE POTENTIAL FOR A FEW OF THE PERENNIAL SNOWBELT LOCATIONS
ACROSS FAR NW WARREN COUNTY PICKING UP MINIMAL WARNING CRITERIA
SNOWS OF 5-8 INCHES THROUGH MONDAY MORNING. THE REST OF WARREN AND
MCKEAN COUNTIES WOULD LIKELY SEE BETWEEN 1 AND 3 INCHES DURING
THIS SAME PERIOD.
SUNDAY WILL BE COLD AND BREEZY WITH FLURRIES AND A FEW SNOW
SHOWERS ACROSS THE LAURELS...AND AND PERHAPS A FEW LIGHT SNOW
SHOWERS OR FLURRIES BLEEDING INTO THE CENTRAL MOUNTAINS AT TIMES.
HIGH TEMPS WILL RANGE FROM NEAR 32 ACROSS THE NRN AND WRN
MOUNTAINS...AND UPPER 30S TO L40S ACROSS THE CENTRAL AND SE
VALLEY LOCATIONS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
LOOKING AT A SEE-SAW WEATHER PATTERN THIS PERIOD AS WE START OFF
THE PERIOD WITH A DEEPENING RELATIVE CHILL AS A SERIES OF
SHORTWAVE TROFS REINFORCE COOLER AIR ESTABLISHED OVER THE REGION
THIS WEEKEND...BEFORE THE START OF THE LONG TERM PERIOD. EARLY NEXT
WEEK THE PATTERN IS FORECAST TO TRANSITION TO A ZONAL FLOW THEN HEIGHTS
RISE OVER THE EASTERN U.S. IN RESPONSE TO A DIGGING UPPER TROF
OVER THE CENTRAL ROCKIES.
THE COLD AIR SHOULD SLOWLY EASE ON MONDAY INTO MONDAY NIGHT. WE
BOTTOM OUT -1 TO -1.5SD BELOW NORMAL FOR 850 MB TEMPS SUNDAY INTO
MONDAY EVENING.
AT THE SURFACE HIGH PRESSURE WILL DOMINATE OUR WEATHER TUESDAY TO
FRIDAY...THE CENTER OF THE HIGH WILL DRIFT OVER THE WESTERN
ATLANTIC...THE PATTERN IMPLIES LOW-LEVEL TRAPPED COLD AIR AS WARM
AIR BUILDS IN ALOFT AND A RIDGE BUILDS AT 500 MB TO OUR WEST. A
WARM LOOKING PATTERN ABOVE THE SURFACE. THE DEEP SOUTHWEST FLOW
IMPLIES INCREASED CHANCE RAIN TOWARD THE WEEKEND BUT NOTHING AT
THIS TIME TO FOCUS ON.
THE 850 MB TEMPERATURES WILL BE A BIT ABOVE NORMAL BY
THANKSGIVING AND PERHAPS INTO EARLY SATURDAY. LOTS OF UNCERTAINTY
AND SOME GEFS AND NAEFS MEMBERS SHOW COLD AIR SAGGING SOUTH
FRIDAY-SATURDAY. SO THE GEFS SHOWS SLIGHTLY ABOVE NORMAL
TEMPERATURES WED-FRIDAY BUT LATE FRIDAY-SATURDAY THE 2M
TEMPERATURE PLUMES SHOW HUGE SPREAD AND LOTS OF UNCERTAINTY. WILL
IT GET WARM OR A SHALLOW FRONT SLIDE THROUGH? INITIALLY THE MEDIAN
IS HIGHER THEN THE MEAN...FRIDAY SHOULD BE WARM...SATURDAY THE
MEDIAN IS BELOW THE MEAN...SATURDAY HIGHER PROBABILITY OF BEING
COLDER THAN FORECAST AS WE TEND TO THE MEAN.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
MAIN AVIATION CONCERN THIS EVENING WILL BE THE POSSIBILITY OF
LLWS...AS CORE OF STRONG WINDS ALOFT OVERSPREAD THE AREA IN
ADVANCE OF APPROACHING COLD FRONT. LATEST BUFKIT SOUNDINGS SUPPORT
A BRIEF PERIOD OF LLWS CRITERIA ACROSS MUCH OF CENTRAL PA LATE
THIS EVENING.
COLD FRONT WILL SWEEP THRU CENTRAL PA BTWN 04Z-07Z...ACCOMPANIED
BY A FEW SHRA ACROSS THE W MTNS. MVFR CONDS COULD ACCOMPANY THE
FRONTAL SHOWERS AT KBFD/KJST. HOWEVER...A BIGGER CONCERN MAY
STRONG...GUSTY WSW WINDS ACCOMPANYING AND IMMEDIATELY FOLLOWING
THE FRONTAL PASSAGE. HRRR AND LATEST NAM SOUNDINGS INDICATE THE
POSSIBILITY OF GUSTS BTWN 35-40KTS AT KBFD/KJST BTWN 04Z-07Z...WITH
SOMEWHAT WEAKER GUSTS FURTHER EAST.
COLD AIR FLOWING OVER THE GREAT LAKES WILL PRODUCE LAKE EFFECT
SNOW SHOWERS ACROSS PORTIONS OF NW PA LATE TONIGHT AND SUNDAY.
HOWEVER...LATEST MDL DATA SUGGESTS THE SIG VIS REDUCTIONS WILL
REMAIN JUST NORTHWEST OF KBFD. ELSEWHERE...WIDESPREAD VFR CONDS
APPEAR VERY LIKELY THRU SUNDAY WITH THE POSSIBLE EXCEPTION OF OCNL
MVFR CIGS AT KJST.
OUTLOOK...SUNDAY-WEDNESDAY
MON-TUE...MVFR WITH CHC -SHSN NW. VFR/NO SIG WX ELSEWHERE.
WED-THU...VFR/NO SIG WX.
&&
.CLIMATE...
ISSUED AT 148 AM EST SAT NOV 21 2015
WITH 10 DAYS LEFT IN THE MONTH...PRELIMINARY CLIMATE DATA
INDICATES THAT NOVEMBER 2015 IS CURRENTLY ON TRACK TO BE THE
WARMEST NOVEMBER ON RECORD AT OUR TWO LONG TERM CLIMATE SITES:
HARRISBURG AND WILLIAMSPORT. A CONTINUOUS WEATHER RECORD HAS BEEN
KEPT AT EACH SITE SINCE 1888 AND 1895 RESPECTIVELY.
THROUGH 11/20...
THE AVG. MONTHLY TEMPERATURE AT HARRISBURG IS 53.2 DEGREES OR
+7.2 DEGREES ABOVE NORMAL.
THE AVG. MONTHLY TEMPERATURE AT WILLIAMSPORT IS 50.9 DEGREES OR
+7.5 DEGREES ABOVE NORMAL.
THE TOP 5 WARMEST NOVEMBERS (CURRENT RANKINGS)
MDT: 2015 (53.2), 1931 (51.3), 1975 (50.0), 1999 (49.3), 1994
(49.0)
IPT: 2015 (50.9), 1931 (48.8), 1902 (47.3), 2009/1972 (47.2), 1913
(46.3)
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW WATCH FROM 1 AM EST SUNDAY THROUGH LATE
SUNDAY NIGHT FOR PAZ004.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...GRUMM/GARTNER
AVIATION...FITZGERALD/LA CORTE
CLIMATE...