Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 11/28/11
AREA FORECAST DISCUSSION
NWS DENVER CO
1210 PM MST SAT NOV 26 2011
.UPDATE...HAVE OPTED TO CANCEL THE HIGH WIND WARNING FOR THE
NORTHEAST PLAINS. LESS THAN CRITERIA CONDITIONS AT THIS TIME AND
DO NOT ANTICIPATE IT WORSENING.
&&
.PREV DISCUSSION... /ISSUED 914 AM MST SAT NOV 26 2011/
UPDATE...ONLY MINOR ADJUSTMENTS TO THE GRIDS AT THIS TIME.
ALTHOUGH IT WILL BE WINDY ACROSS THE PLAINS...THERE IS STILL SOME
QUESTION AS TO WHETHER A WARNING IS WARRANTED. WL HOLD ON TO THE
HIGHLIGHT FOR NOW AND SEE HOW THINGS DEVELOP BEFORE THE NEXT
UPDATE TO THE NPW WHICH WILL BE AROUND 1830Z.
&&
.AVIATION...NO MAJOR ADJUSTMENTS AT THIS TIME. THE MAIN CONCERN
WILL REVOLVE AROUND THE DEVELOPMENT OF THE LONGMONT ANTICYCLONE
THIS AFTERNOON. THIS HAS ALREADY BEEN ADDRESSED IN THE PRVS
DISCUSSION AND SEE NO REASON TO TAMPER MUCH WITH THE TERMINAL FCSTS
I INHERITED.
.PREV DISCUSSION... /ISSUED 320 AM MST SAT NOV 26 2011/
SHORT TERM...AN UPPER LEVEL TROUGH WILL QUICKLY MOVE EAST OF THE
AREA THIS MORNING WITH SNOW ENDING IN THE MTNS AND OVER THE FAR NERN
PLAINS BY SUNRISE. WINDS WILL REMAIN GUSTY OVER THE NERN PLAINS
THRU EARLY AFTN BEFORE GRADUALLY DECREASING BY LATE AFTN. BASED ON
CURRENT DATA MOST GUSTS WILL BE AROUND 50 MPH HOWEVER STILL COULD
SEE A FEW HIGHER GUSTS THRU EARLY AFTN SO WILL KEEP HIGH WIND
WARNING IN PLACE ALTHOUGH IT PROBABLY COULD BE CANCELED BY 21Z. AS
FAR AS FIRE WEATHER WATCH LATEST HRR SHOWS HUMIDITY LEVELS ONLY
DROPPING TO 35-40 PERCENT OVER THE NERN PLAINS THIS AFTN WITH TEMPS
AROUND 40 DEGREES. IN ADDITION THERE WAS SOME SNOW OVERNIGHT WITH
ACCUMULATIONS UP TO AN INCH IN SPOTS. ALTHOUGH WINDS WILL BE GUSTY
BELIEVE THREAT IS LOW ENOUGH TO NOT ISSUE A RED FLAG WARNING. AS
FOR HIGHS THIS AFTN WILL KEEP READINGS MAILY IN THE UPPER 30S TO
LOWER 40S OVER THE NERN PLAINS WITH MID 40S CLOSER TO THE FOOTHILLS.
FOR TONIGHT WINDS WILL QUICKLY DIMINISH OVER THE PLAINS SHORTLY
AFTER SUNSET WITH DRY CONDITIONS OVER THE ENTIRE CWA.
LONG TERM...STRONG NORTH-NORTHWESTERLY FLOW ALOFT IS PROGGED TO
DECREASE ACROSS THE CWA ON SUNDAY AS AN UPPER RIDGE MOVES IN. THE
RIDGE AXIS MOVES ACROSS THE FORECAST AREA LATE SUNDAY NIGHT INTO MID
DAY MONDAY...WITH WEAKER ZONAL FLOW ALOFT. LATE MONDAY AND MONDAY
NIGHT...A WEAK UPPER TROUGH IS PROGGED TO MOVE IN WITH WESTERLY FLOW
ALOFT ON THE INCREASE MONDAY EVENING. THE SYNOPTIC SCALE ENERGY IS
NEGLIGIBLE SUNDAY AND SUNDAY NIGHT...THEN WEAK UPWARD QG VERTICAL
VELOCITY IS PROGGED MONDAY AFTERNOON INTO THE EARLY EVENING HOURS.
AFTER THAT...WEAK DOWNWARD MOTION MOVES IN FOR THE REST OF MONDAY
NIGHT. THE LOW LEVEL PRESSURE AND WIND FIELDS KEEP A DECENT
GRADIENT IN PLACE...WITH LOW PRESSURE EAST OF THE MOUNTAINS.
DOWNSLOPING BOUNDARY LAYER WINDS ARE A GOOD BET SUNDAY THROUGH MUCH
OF MONDAY. A WEAK COLD FRONT IS PROGGED TO MOVE INTO THE PLAINS
MONDAY AFTERNOON WITH BOUNDARY LAYER UPSLOPE CONTINUING PAST
MIDNIGHT MONDAY NIGHT. FOR MOISTURE...SUNDAY LOOKS PRETTY DRY...
WITH JUST OF A BIT OF UPPER LEVEL MOISTURE PROGGED SUNDAY NIGHT INTO
MONDAY. BY 00Z TUESDAY...MOISTURE INCREASES A BIT BEHIND THE FRONT
..WITH THE GFS SHOWING IT TO GET FAIRLY DEEP OVER THE FOOTHILLS AND
WESTERN CWA PLAINS. THE NAM HAS LESS. THE MOUNTAINS STAY FAIRLY
DRY. BOTH MODELS SHOW IT PRETTY DRY BY 12Z TUESDAY MORNING...JUST A
BIT OF MID LEVEL MOISTURE ON THE NAM. THE ONLY MEASURABLE
PRECIPITATION NOTED ON THE QPF FIELDS FROM SUNDAY THROUGH TUESDAY
MORNING...IS A TAD OVER THE FOOTHILLS AND ADJACENT PLAINS ON THE GFS
MONDAY EVENING. WILL GO WITH NO POPS FOR CWA THROUGH THE PERIODS.
WILL WATCH FOR THE MONDAY AFTERNOON/EVENING UPSLOPE ON FURTHER MODEL
RUNS. FOR TEMPERATURES...SUNDAY`S HIGHS ARE 8-11 C WARMER THAN
TODAY`S EXPECTED READINGS. MONDAY`S HIGHS ARE A TAD COOLER THAN
SUNDAY`S...AT LEAST FOR THE PLAINS. FOR THE LATER DAYS...TUESDAY
THROUGH FRIDAY...MODELS HAVE MORE UPPER RIDGING TUESDAY INTO
WEDNESDAY FOR THE CWA. BY WEDNESDAY NIGHT AND THURSDAY...MODELS
SHOW A DECENT CLOSED LOW OVER THE WEST CENTRAL U.S. COAST. IT MOVES
LITTLE THROUGH FRIDAY...DEPENDING ON THE MODEL. THE GFS BRINGS A
FAIRLY COLD AIRMASS AND UPSLOPE TO THE PLAINS WEDNESDAY EVENING.
THE ECMWF DOESN`T SHOW THIS UNTIL THURSDAY AFTERNOON. BOTH HAVE A
FAIRLY COLD AIRMASS IN PLACE ON FRIDAY. THE MODELS HAVE BEEN ALL
OVER THE HE PLACE WITH THIS FEATURE THE LAST FEW RUNS. CONFIDENCE
IS LOW. WILL LEAVE THE EXTENDED-BLENDED-GFE STUFF PRETTY MUCH
ALONE.
AVIATION...WINDS HAVE REMAINED GUSTY OUT OF THE NORTH AT 20-30 MPH
EARLY THIS MORNING HOWEVER LATEST HRRR SHOWS THEM DECREASING BY
SUNRISE TO THE 10-20 MPH RANGE. BY MID MORNING THE HRRR SHOWS A
WELL DEFINED LONGMONT ANTICYCLONE WITH THE CENTER STAYING TO THE NW
OF THE AIRPORT THRU THE AFTN. THIS KEEPS WINDS AT THE AIRPORT NNW
THRU EARLY AFTN WITH SPEEDS IN THE 15-25 MPH WITH SOME GUSTS TO
30-35 MPH AT TIMES THRU 20Z. AFTER 20Z THE HRRR SHOWS WINDS
DECREASING TO 10-20 MPH AND BECOMING MORE NELY AS THE ANTICYCLONE
SHIFTS A BIT FURTHER EAST. BY SUNSET THE WINDS SHOULD BECOME LIGHT
ESE AND THEN MORE SLY BY 03Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COOPER
LONG TERM....RJK
AREA FORECAST DISCUSSION
NWS DENVER CO
914 AM MST SAT NOV 26 2011
.UPDATE...ONLY MINOR ADJUSTMENTS TO THE GRIDS AT THIS TIME.
ALTHOUGH IT WILL BE WINDY ACROSS THE PLAINS...THERE IS STILL SOME
QUESTION AS TO WHETHER A WARNING IS WARRANTED. WL HOLD ON TO THE
HIGHLIGHT FOR NOW AND SEE HOW THINGS DEVELOP BEFORE THE NEXT
UPDATE TO THE NPW WHICH WILL BE AROUND 1830Z.
&&
.AVIATION...NO MAJOR ADJUSTMENTS AT THIS TIME. THE MAIN CONCERN
WILL REVOLVE AROUND THE DEVELOPMENT OF THE LONGMONT ANTICYCLONE
THIS AFTERNOON. THIS HAS ALREADY BEEN ADDRESSED IN THE PRVS
DISCUSSION AND SEE NO REASON TO TAMPER MUCH WITH THE TERMINAL FCSTS
I INHERITED.
&&
.PREV DISCUSSION... /ISSUED 320 AM MST SAT NOV 26 2011/
SHORT TERM...AN UPPER LEVEL TROUGH WILL QUICKLY MOVE EAST OF THE
AREA THIS MORNING WITH SNOW ENDING IN THE MTNS AND OVER THE FAR NERN
PLAINS BY SUNRISE. WINDS WILL REMAIN GUSTY OVER THE NERN PLAINS
THRU EARLY AFTN BEFORE GRADUALLY DECREASING BY LATE AFTN. BASED ON
CURRENT DATA MOST GUSTS WILL BE AROUND 50 MPH HOWEVER STILL COULD
SEE A FEW HIGHER GUSTS THRU EARLY AFTN SO WILL KEEP HIGH WIND
WARNING IN PLACE ALTHOUGH IT PROBABLY COULD BE CANCELED BY 21Z. AS
FAR AS FIRE WEATHER WATCH LATEST HRR SHOWS HUMIDITY LEVELS ONLY
DROPPING TO 35-40 PERCENT OVER THE NERN PLAINS THIS AFTN WITH TEMPS
AROUND 40 DEGREES. IN ADDITION THERE WAS SOME SNOW OVERNIGHT WITH
ACCUMULATIONS UP TO AN INCH IN SPOTS. ALTHOUGH WINDS WILL BE GUSTY
BELIEVE THREAT IS LOW ENOUGH TO NOT ISSUE A RED FLAG WARNING. AS
FOR HIGHS THIS AFTN WILL KEEP READINGS MAILY IN THE UPPER 30S TO
LOWER 40S OVER THE NERN PLAINS WITH MID 40S CLOSER TO THE FOOTHILLS.
FOR TONIGHT WINDS WILL QUICKLY DIMINISH OVER THE PLAINS SHORTLY
AFTER SUNSET WITH DRY CONDITIONS OVER THE ENTIRE CWA.
LONG TERM...STRONG NORTH-NORTHWESTERLY FLOW ALOFT IS PROGGED TO
DECREASE ACROSS THE CWA ON SUNDAY AS AN UPPER RIDGE MOVES IN. THE
RIDGE AXIS MOVES ACROSS THE FORECAST AREA LATE SUNDAY NIGHT INTO MID
DAY MONDAY...WITH WEAKER ZONAL FLOW ALOFT. LATE MONDAY AND MONDAY
NIGHT...A WEAK UPPER TROUGH IS PROGGED TO MOVE IN WITH WESTERLY FLOW
ALOFT ON THE INCREASE MONDAY EVENING. THE SYNOPTIC SCALE ENERGY IS
NEGLIGIBLE SUNDAY AND SUNDAY NIGHT...THEN WEAK UPWARD QG VERTICAL
VELOCITY IS PROGGED MONDAY AFTERNOON INTO THE EARLY EVENING HOURS.
AFTER THAT...WEAK DOWNWARD MOTION MOVES IN FOR THE REST OF MONDAY
NIGHT. THE LOW LEVEL PRESSURE AND WIND FIELDS KEEP A DECENT
GRADIENT IN PLACE...WITH LOW PRESSURE EAST OF THE MOUNTAINS.
DOWNSLOPING BOUNDARY LAYER WINDS ARE A GOOD BET SUNDAY THROUGH MUCH
OF MONDAY. A WEAK COLD FRONT IS PROGGED TO MOVE INTO THE PLAINS
MONDAY AFTERNOON WITH BOUNDARY LAYER UPSLOPE CONTINUING PAST
MIDNIGHT MONDAY NIGHT. FOR MOISTURE...SUNDAY LOOKS PRETTY DRY...
WITH JUST OF A BIT OF UPPER LEVEL MOISTURE PROGGED SUNDAY NIGHT INTO
MONDAY. BY 00Z TUESDAY...MOISTURE INCREASES A BIT BEHIND THE FRONT
..WITH THE GFS SHOWING IT TO GET FAIRLY DEEP OVER THE FOOTHILLS AND
WESTERN CWA PLAINS. THE NAM HAS LESS. THE MOUNTAINS STAY FAIRLY
DRY. BOTH MODELS SHOW IT PRETTY DRY BY 12Z TUESDAY MORNING...JUST A
BIT OF MID LEVEL MOISTURE ON THE NAM. THE ONLY MEASURABLE
PRECIPITATION NOTED ON THE QPF FIELDS FROM SUNDAY THROUGH TUESDAY
MORNING...IS A TAD OVER THE FOOTHILLS AND ADJACENT PLAINS ON THE GFS
MONDAY EVENING. WILL GO WITH NO POPS FOR CWA THROUGH THE PERIODS.
WILL WATCH FOR THE MONDAY AFTERNOON/EVENING UPSLOPE ON FURTHER MODEL
RUNS. FOR TEMPERATURES...SUNDAY`S HIGHS ARE 8-11 C WARMER THAN
TODAY`S EXPECTED READINGS. MONDAY`S HIGHS ARE A TAD COOLER THAN
SUNDAY`S...AT LEAST FOR THE PLAINS. FOR THE LATER DAYS...TUESDAY
THROUGH FRIDAY...MODELS HAVE MORE UPPER RIDGING TUESDAY INTO
WEDNESDAY FOR THE CWA. BY WEDNESDAY NIGHT AND THURSDAY...MODELS
SHOW A DECENT CLOSED LOW OVER THE WEST CENTRAL U.S. COAST. IT MOVES
LITTLE THROUGH FRIDAY...DEPENDING ON THE MODEL. THE GFS BRINGS A
FAIRLY COLD AIRMASS AND UPSLOPE TO THE PLAINS WEDNESDAY EVENING.
THE ECMWF DOESN`T SHOW THIS UNTIL THURSDAY AFTERNOON. BOTH HAVE A
FAIRLY COLD AIRMASS IN PLACE ON FRIDAY. THE MODELS HAVE BEEN ALL
OVER THE HE PLACE WITH THIS FEATURE THE LAST FEW RUNS. CONFIDENCE
IS LOW. WILL LEAVE THE EXTENDED-BLENDED-GFE STUFF PRETTY MUCH
ALONE.
AVIATION...WINDS HAVE REMAINED GUSTY OUT OF THE NORTH AT 20-30 MPH
EARLY THIS MORNING HOWEVER LATEST HRRR SHOWS THEM DECREASING BY
SUNRISE TO THE 10-20 MPH RANGE. BY MID MORNING THE HRRR SHOWS A
WELL DEFINED LONGMONT ANTICYCLONE WITH THE CENTER STAYING TO THE NW
OF THE AIRPORT THRU THE AFTN. THIS KEEPS WINDS AT THE AIRPORT NNW
THRU EARLY AFTN WITH SPEEDS IN THE 15-25 MPH WITH SOME GUSTS TO
30-35 MPH AT TIMES THRU 20Z. AFTER 20Z THE HRRR SHOWS WINDS
DECREASING TO 10-20 MPH AND BECOMING MORE NELY AS THE ANTICYCLONE
SHIFTS A BIT FURTHER EAST. BY SUNSET THE WINDS SHOULD BECOME LIGHT
ESE AND THEN MORE SLY BY 03Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ042-
048>051.
&&
$$
SHORT TERM...COOPER
LONG TERM....RJK
AVIATION...COOPER
AREA FORECAST DISCUSSION
NWS DENVER CO
320 AM MST SAT NOV 26 2011
.SHORT TERM...AN UPPER LEVEL TROUGH WILL QUICKLY MOVE EAST OF THE
AREA THIS MORNING WITH SNOW ENDING IN THE MTNS AND OVER THE FAR NERN
PLAINS BY SUNRISE. WINDS WILL REMAIN GUSTY OVER THE NERN PLAINS
THRU EARLY AFTN BEFORE GRADUALLY DECREASING BY LATE AFTN. BASED ON
CURRENT DATA MOST GUSTS WILL BE AROUND 50 MPH HOWEVER STILL COULD
SEE A FEW HIGHER GUSTS THRU EARLY AFTN SO WILL KEEP HIGH WIND
WARNING IN PLACE ALTHOUGH IT PROBABLY COULD BE CANCELED BY 21Z. AS
FAR AS FIRE WEATHER WATCH LATEST HRR SHOWS HUMIDITY LEVELS ONLY
DROPPING TO 35-40 PERCENT OVER THE NERN PLAINS THIS AFTN WITH TEMPS
AROUND 40 DEGREES. IN ADDITION THERE WAS SOME SNOW OVERNIGHT WITH
ACCUMULATIONS UP TO AN INCH IN SPOTS. ALTHOUGH WINDS WILL BE GUSTY
BELIEVE THREAT IS LOW ENOUGH TO NOT ISSUE A RED FLAG WARNING. AS
FOR HIGHS THIS AFTN WILL KEEP READINGS MAILY IN THE UPPER 30S TO
LOWER 40S OVER THE NERN PLAINS WITH MID 40S CLOSER TO THE FOOTHILLS.
FOR TONIGHT WINDS WILL QUICKLY DIMINISH OVER THE PLAINS SHORTLY
AFTER SUNSET WITH DRY CONDITIONS OVER THE ENTIRE CWA.
.LONG TERM...STRONG NORTH-NORTHWESTERLY FLOW ALOFT IS PROGGED TO
DECREASE ACROSS THE CWA ON SUNDAY AS AN UPPER RIDGE MOVES IN. THE
RIDGE AXIS MOVES ACROSS THE FORECAST AREA LATE SUNDAY NIGHT INTO MID
DAY MONDAY...WITH WEAKER ZONAL FLOW ALOFT. LATE MONDAY AND MONDAY
NIGHT...A WEAK UPPER TROUGH IS PROGGED TO MOVE IN WITH WESTERLY FLOW
ALOFT ON THE INCREASE MONDAY EVENING. THE SYNOPTIC SCALE ENERGY IS
NEGLIGIBLE SUNDAY AND SUNDAY NIGHT...THEN WEAK UPWARD QG VERTICAL
VELOCITY IS PROGGED MONDAY AFTERNOON INTO THE EARLY EVENING HOURS.
AFTER THAT...WEAK DOWNWARD MOTION MOVES IN FOR THE REST OF MONDAY
NIGHT. THE LOW LEVEL PRESSURE AND WIND FIELDS KEEP A DECENT
GRADIENT IN PLACE...WITH LOW PRESSURE EAST OF THE MOUNTAINS.
DOWNSLOPING BOUNDARY LAYER WINDS ARE A GOOD BET SUNDAY THROUGH MUCH
OF MONDAY. A WEAK COLD FRONT IS PROGGED TO MOVE INTO THE PLAINS
MONDAY AFTERNOON WITH BOUNDARY LAYER UPSLOPE CONTINUING PAST
MIDNIGHT MONDAY NIGHT. FOR MOISTURE...SUNDAY LOOKS PRETTY DRY...
WITH JUST OF A BIT OF UPPER LEVEL MOISTURE PROGGED SUNDAY NIGHT INTO
MONDAY. BY 00Z TUESDAY...MOISTURE INCREASES A BIT BEHIND THE FRONT
...WITH THE GFS SHOWING IT TO GET FAIRLY DEEP OVER THE FOOTHILLS AND
WESTERN CWA PLAINS. THE NAM HAS LESS. THE MOUNTAINS STAY FAIRLY
DRY. BOTH MODELS SHOW IT PRETTY DRY BY 12Z TUESDAY MORNING...JUST A
BIT OF MID LEVEL MOISTURE ON THE NAM. THE ONLY MEASURABLE
PRECIPITATION NOTED ON THE QPF FIELDS FROM SUNDAY THROUGH TUESDAY
MORNING...IS A TAD OVER THE FOOTHILLS AND ADJACENT PLAINS ON THE GFS
MONDAY EVENING. WILL GO WITH NO POPS FOR CWA THROUGH THE PERIODS.
WILL WATCH FOR THE MONDAY AFTERNOON/EVENING UPSLOPE ON FURTHER MODEL
RUNS. FOR TEMPERATURES...SUNDAY`S HIGHS ARE 8-11 C WARMER THAN
TODAY`S EXPECTED READINGS. MONDAY`S HIGHS ARE A TAD COOLER THAN
SUNDAY`S...AT LEAST FOR THE PLAINS. FOR THE LATER DAYS...TUESDAY
THROUGH FRIDAY...MODELS HAVE MORE UPPER RIDGING TUESDAY INTO
WEDNESDAY FOR THE CWA. BY WEDNESDAY NIGHT AND THURSDAY...MODELS
SHOW A DECENT CLOSED LOW OVER THE WEST CENTRAL U.S. COAST. IT MOVES
LITTLE THROUGH FRIDAY...DEPENDING ON THE MODEL. THE GFS BRINGS A
FAIRLY COLD AIRMASS AND UPSLOPE TO THE PLAINS WEDNESDAY EVENING.
THE ECMWF DOESN`T SHOW THIS UNTIL THURSDAY AFTERNOON. BOTH HAVE A
FAIRLY COLD AIRMASS IN PLACE ON FRIDAY. THE MODELS HAVE BEEN ALL
OVER THE HE PLACE WITH THIS FEATURE THE LAST FEW RUNS. CONFIDENCE
IS LOW. WILL LEAVE THE EXTENDED-BLENDED-GFE STUFF PRETTY MUCH
ALONE.
&&
.AVIATION...WINDS HAVE REMAINED GUSTY OUT OF THE NORTH AT 20-30 MPH
EARLY THIS MORNING HOWEVER LATEST HRRR SHOWS THEM DECREASING BY
SUNRISE TO THE 10-20 MPH RANGE. BY MID MORNING THE HRRR SHOWS A
WELL DEFINED LONGMONT ANTICYCLONE WITH THE CENTER STAYING TO THE NW
OF THE AIRPORT THRU THE AFTN. THIS KEEPS WINDS AT THE AIRPORT NNW
THRU EARLY AFTN WITH SPEEDS IN THE 15-25 MPH WITH SOME GUSTS TO
30-35 MPH AT TIMES THRU 20Z. AFTER 20Z THE HRRR SHOWS WINDS
DECREASING TO 10-20 MPH AND BECOMING MORE NELY AS THE ANTICYCLONE
SHIFTS A BIT FURTHER EAST. BY SUNSET THE WINDS SHOULD BECOME LIGHT
ESE AND THEN MORE SLY BY 03Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...HIGH WIND WARNING UNTIL 5 PM THIS
AFTERNOON FOR NERN CO ZONES 42..48..49..50 AND 51.
&&
$$
RPK/RJK
AREA FORECAST DISCUSSION
NWS NEW YORK NY
946 PM EST SUN NOV 27 2011
.SYNOPSIS...
HIGH PRESSURE REMAINS OFFSHORE TO THE EAST MONDAY WHILE A LOW
PRESSURE SYSTEM TRACKS EAST ACROSS CANADA...DRAGGING A COLD FRONT
THROUGH NEW ENGLAND. A STORM SYSTEM WILL SLOWLY TRACK FROM THE UPPER
OHIO RIVER VALLEY TO THE CANADIAN MARITIME PROVINCES BY THURSDAY
MORNING. WEAK HIGH PRESSURE BUILDS IN THURSDAY AND THURSDAY
NIGHT...FOLLOWED BY A WEAK COLD FRONT ON FRIDAY. HIGH PRESSURE
THEN BUILDS IN FOR THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
WATER VAPOR SHOWS A DEEP LAYERED RIDGE...WITH THE RIDGE AXIS TO
OUR SW...AND GUIDANCE SUGGESTS THE STATUS QUO WILL MAINTAIN ITSELF
THROUGH TONIGHT. THE RESULT IS MINIMAL IF ANY FORCING...SO HAVE
REMOVED ALL PRECIPITATION FROM TONIGHT. UPDATED POPS ARE
CONSISTENT WITH A BLEND OF HRRR HOURLY AND SREF AND NAM 3-HOUR
POPS - WEIGHED MORE TOWARDS THE HRRR IN THE FIRST SIX HOURS OR SO.
STILL APPEAR ON TRACK FOR FOG OR MORE LIKELY STRATUS TO DEVELOP
OVERNIGHT. QUESTION IS WILL THE FOG BECOME DENSE OR...WILL
ULTIMATELY LOW LEVEL STRATUS WIN OUT. FOR NOW BEGINNING TO LEAN
MORE TOWARDS THE STRATUS BASED ON BUFKIT PROFILES...BUT NOT
CONFIDENT ENOUGH TO REMOVE FOG FROM ZONES AT THIS TIME. HOWEVER IF
THE FOG WINDS OUT...WILL LIKE SEE DENSE FOG...EVEN MORE WIDESPREAD
THEN LAST NIGHT.
WEAK WARM ADVECTION CONTINUES THROUGH THE NIGHT AND TEMPERATURES
ALONG THE COAST ARE NOT EXPECTED TO DROP OFF TOO MUCH FROM THE
LATE EVENING LEVELS...SO RAISED LOWS A COUPLE OF DEGREES. ALSO
MIXING DOWN SOME SOME 30 KT WINDS AT 1K FT WITH GUSTS INTO THE LOW
20S. HIGHER WINDS ALOFT REMAIN FOR THE NEXT SEVERAL HOURS AND
UPPED GUSTS ALONG COASTAL LONG ISLAND.
ALSO MADE MINOR ADJUSTMENTS TO DEWPOINTS AND TEMPERATURES BASED
ON LATEST TRENDS IN OBSERVATIONS.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
THE LIGHT RAIN/DRIZZLE OVER FAR NW ZONES WILL REMAIN POSSIBLE
THROUGH AROUND 16Z BEFORE THINGS DRY UP FOR THE REST OF THE
PERIOD. HIGH PRESSURE REMAINS TO THE EAST...WITH TWO LOW PRESSURE
SYSTEMS BECOMING THE NEXT FOCUS. THE ONE LOW MOVING THROUGH CANADA
WILL DRAG A COLD FRONT THROUGH NORTHERN NEW ENGLAND. CURRENT
GUIDANCE INDICATES THE FRONT WILL REMAIN NORTH OF THE AREA...AND
THUS SHOULDN/T AFFECT THE CWA. THE SECOND LOW FORMS OVER THE
SOUTHEASTERN US MONDAY MORNING AND PUSHES NORTH THROUGH THE
DAY...SETTLING OVER TN AND KY FOR MON NIGHT. THE UPPER LEVEL RIDGE
WILL BEGIN WEAKENING AS WELL MONDAY...AHEAD OF A DEVELOPING UPPER
LEVEL LOW OVER THE MIDWEST.
SOUTHWESTERLY FLOW WILL PERSIST THROUGH MONDAY...WITH THE WINDS
SHIFTING BACK TO A SOUTHERLY FLOW FOR MON NIGHT. SIDED MORE WITH
A GFS/MOS MIX FOR GUIDANCE FOR WINDS DURING THIS PERIOD AS THE NAM
BRINGS THE WINDS AROUND TO THE EAST MUCH QUICKER...BY 12Z TUES
MORNING. CURRENT THINKING WILL BE THE LOW IS SLIGHTLY SLOWER...AND
THE WINDS WILL BE MORE SOUTHEASTERLY BY 12Z TUES MORNING. THE NAM
ALSO WANTS TO HAVE THE HIGH PRESSURE MORE DOMINANT MON NIGHT...SO
SIDED WITH THE WEAKER HIGH WITH THE GFS. WITH THE GFS
TIMING...BROUGHT IN A SLIGHT CHANCE FOR POPS LATE IN THE PERIOD MON
NIGHT FOR THE FAR WESTERN PORTION OF THE CWA. WITH THE LOWER LEVEL
MOISTURE REMAINING ELEVATED...HAVE ALSO INCLUDED PATCHY FOG AROUND
THE CWA FOR MON NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
GFS IN GENERAL TOO PROGRESSIVE AS HAS BEEN ITS BIAS OF LATE...SO
USED A NAM/ECMWF/SREF BLEND TUESDAY-WEDNESDAY...THEN FOLLOWED THE
ECMWF WEDNESDAY NIGHT-SUNDAY.
UPPER RIDGE AXIS OVER THE REGION SUPPORTS DAMMING HIGH SIGNATURE
OVER THE REGION TUESDAY INTO TUESDAY NIGHT. THIS WILL HELP TO SERVE
TO IMPEDE PROGRESS OF PRECIPITATION INTO THE REGION AHEAD OF CUTOFF
SYSTEM MOVING INTO THE WEST-CENTRAL APPALACHIANS BY TUESDAY EVENING.
AS A RESULT ONLY BRING POPS UP TO LIKELY OVER WESTERN 1/5 OF CWA AND
JUST BARELY TO CHANCE OVER FAR EASTERN PARTS OF THE CWA BY LATE
AFTERNOON.
STRONG ISENTROPIC LIFT DEVELOPS TUESDAY NIGHT...ALONG WITH 50-60 KT
LOW LEVEL JET IMPACTING REGION...ALLOWING FOR MODERATE TO POSSIBLY
LOCALLY HEAVY RAINFALL TO DEVELOP ACROSS THE TRI-STATE TUESDAY
NIGHT. WITH SHOWALTERS 0 TO -2...HAVE ADDED SLIGHT CHANCE OF THUNDER
TO ALL AREAS EAST OF THE HUDSON PLUS MOST OF NE NJ. CATEGORICAL POPS
THROUGHOUT TUESDAY NIGHT (DEVELOP FROM W TO E).
SHOWERS SHOULD TAPER OFF FROM W TO E MAINLY DURING WEDNESDAY
MORNING. THERE ARE SOME HINTS THAT FAR NW ZONES COULD END UP GETTING
SOME DEFORMATION AXIS PRECIPITATION WEDNESDAY AFTERNOON...BUT TOO
MUCH UNCERTAINTY TO REFLECT THIS IN FORECAST AT THIS TIME. COULD SEE
SOME GUSTY SW-W WINDS BEHIND THE COLD FRONT.
IMPROVING CONDITIONS WEDNESDAY NIGHT AS CLOSED LOW OPENS UP AND
PILLS TO THE NE...WITH WEAK RIDGING BEGINNING TO BUILD IN LATE.
SPLIT FLOW OVER THE EASTERN U.S. THURSDAY/THURSDAY NIGHT...WITH A
SOUTHERN STREAM TROUGH PASSING TO THE S...AND WEAK RIDGING OVER US
EVOLVING INTO SW FLOW ALOFT.
500 HPA TROUGH APPROACHES FRIDAY THEN CROSSES REGION FRIDAY NIGHT.
WITH LIMITED LOW LEVEL MOISTURE TO WORK WITH...GOING WITH A DRY
PASSAGE FOR NOW.
STRONG RIDGE RE-ESTABLISHES ITSELF OVER FLORIDA...WITH ITS RIDGE
AXIS PUSHING UP INTO THE NE STATES SATURDAY...THEN SLIDING OFFSHORE
SUNDAY. THIS SHOULD KEEP THE REGION DRY.
FOR TEMPERATURES...
FOR HIGHS TUESDAY...BLENDED MAV/MET GUIDANCE. HAVE SUSPICIONS THAT
THIS COULD ULTIMATELY END UP BEING ON THE WARM SIDE...WITH
TEMPERATURES STRUGGLING TO GET OUT OF THE 50S WITH THE TRI-STATE
BEING STUCK UNDER LOW CLOUDS/OCCASIONAL DRIZZLE DUE TO ONSHORE
FLOW...BUT STILL NEED TO SEE A FEW MORE THINGS WORK THEMSELVES OUT
BEFORE GOING THIS ROUTE.
FOR LOWS TUESDAY NIGHT...CONTINUED WITH MAV/MET BLEND...WEIGHING
TOWARDS WARMER GUIDANCE AS MAV TRIES TO COOL THINGS OFF TO MUCH AS
IT ENDS PRECIP TOO SOON.
FOR HIGHS WEDNESDAY USED A MEX/MEX ENSEMBLE MEAN BLEND...THEN
CONTINUED TO USE THIS...WITH HPC GUIDANCE BLENDED IN
THURSDAY-SUNDAY. MAIN PLACE HPC GUIDANCE CHANGED THINGS WAS NEXT
WEEKEND WHERE GFS SOLUTION IS NOTABLY COOLER THAN CURRENTLY
PREFERRED ECMWF SOLUTION.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE REMAINS EAST OF THE TERMINALS WITH A DEEP SOUTHERLY
FLOW. CONDITIONS START OFF AT VFR...HOWEVER STRATUS IS LIKELY TO
DEVELOP LATE THIS EVENING INTO THE OVERNIGHT TOWARD 07Z...WITH
MVFR CEILINGS. DO NOT HAVE HIGH CONFIDENCE IN IFR CEILINGS
DEVELOPING...AND MODERATE IF ANY STRATUS DEVELOPS. WITH THE UPDATE
REMOVED IFR CEILINGS FROM THE TERMINALS. IF VISIBILITIES LOWER
WILL BE BRIEFLY TO MVFR. CONFIDENCE FOR FOG DEVELOPMENT LOWER
THAN FOR STRATUS.
IMPROVEMENT BACK TO VFR WILL OCCUR AROUND MID MORNING...13Z TO 15Z.
OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
MONDAY NIGHT...FOG AND STRATUS DEVELOPING WITH MVFR TO IFR
CONDITIONS.
TUESDAY-WEDNESDAY...PERIODS OF SUB-VFR CONDITIONS POSSIBLE IN
SHOWERS/FOG.
THURSDAY-FRIDAY...VFR.
&&
.MARINE...
DEVELOPING SOUTHERLY FLOW BRINGS POTENTIAL FOR LOW CLOUDS OR FOG
LATE TONIGHT INTO MONDAY MORNING. IF IT ENDS UP BEING FOG...COULD
END UP NEEDING DENSE FOG ADVISORIES...ESPECIALLY NEAR THE COAST.
SOUTHWESTERLY WINDS WILL PERSIST THROUGH TONIGHT INTO TOMORROW
BEFORE SHIFTING TO A SOUTHEASTERLY FLOW BY TUES MORNING. PRESSURE
GRADIENT IS EXPECTED TO RELAX A BIT TONIGHT...AS HIGH DRIFTS
FURTHER OFFSHORE AND A FRONTAL BOUNDARY REMAINS OVER THE SAINT
LAWRENCE RIVER VALLEY. THIS WILL ALLOW FOR WINDS TO GRADUALLY
DIMINISH OVERNIGHT. WAVEWATCH GUIDANCE BROUGHT 5 FT WAVES TO THE
EDGE OF THE MARINE ZONES...WHILE PRODUCING MAINLY 4 FT OVER THE
REST OF THE OCEAN WATER ZONES. HAVE OPTIONED TO NOT ISSUE A SCA
FOR WAVES FOR TONIGHT. AS THE WINDS CONTINUE TO WEAKEN
MONDAY...EXPECT THE SEAS TO SUBSIDE FOR THE DAY BEFORE INCREASING
AGAIN LATE MON NIGHT AS THE WINDS INCREASE WITH THE APPROACHING
LOW FROM THE SOUTH.
STRENGTHENING EASTERLY FLOW SHOULD BUILD AT LEAST SEAS TO SCA LEVELS
ON THE COASTAL OCEAN WATERS TUESDAY AFTERNOON...AND COULD QUITE
POSSIBLY RESULT IN GUSTS TO 25 KT ON ALL WATERS BY THEN AS WELL.
GUSTY WINDS CONTINUE TUESDAY NIGHT...THOUGH FEEL MARINE LAYER WILL
PREVENT BULK OF 45-55KT 950 HPA JET FROM MIXING DOWN...SO KEPT GUSTS
TO SCA LEVELS. WIND GUSTS TO SCA LEVELS SHOULD CONTINUE ON ALL
WATERS INTO WEDNESDAY EVENING...BUT SEAS SHOULD REMAIN AT SCA LEVELS
ON THE COASTAL OCEAN ZONES ALL NIGHT.
IT IS POSSIBLE THAT SCA LEVEL SEAS COULD PERSIST ON ANZ-350 ON
THURSDAY...OTHERWISE EXPECT SUB-SCA CONDITIONS ON ALL WATERS INTO
FRIDAY.
&&
.HYDROLOGY...
LIGHT RAIN IS POSSIBLE OVER THE HUDSON RIVER VALLEY TONIGHT...WITH
JUST A TRACE EXPECTED. DRY WEATHER WILL PERSIST THROUGH MONDAY FOR
THE REST OF THE CWA. THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL
FROM LATE TUESDAY INTO WEDNESDAY MORNING. FOR NOW FORECASTING
FROM AROUND 1/2 TO 3/4 AN INCH OF RAINFALL WITH LOCALLY HIGHER
AMOUNTS POSSIBLE. THIS MAKES MINOR URBAN/POOR DRAINAGE FLOODING
THE MOST LIKELY SCENARIO...ESPECIALLY IN AREAS RECEIVING LOCALLY
HEAVY RAINFALL DUE TO PASSING ELEVATED CONVECTION.
&&
.CLIMATE...
THE LATEST GUIDANCE INDICATES THAT HIGHS MONDAY WILL NOT REACH
RECORD HIGH TEMPS. HOWEVER...WITH TEMPS STILL FORECASTED IN THE
LOWER 60S...IT MAY STILL BE POSSIBLE FOR ISOLATED LOCATIONS IN AND
AROUND THE NEW YORK CITY METRO AREA TO COME CLOSE. RECORD HIGH
TEMPS WILL ALSO BE APPROACHED ON TUESDAY...WITH HIGHS ONCE AGAIN
BEING FORECASTED IN THE LOWER TO MID 60S.
FOR MONDAY 11/28
EWR 72/1973
BDR 65/2001
NYC *69/1990
LGA 68/1990
JFK 66/2001
ISP 66/1995
* ALSO OCCURRED IN PREVIOUS YEARS
FOR TUESDAY 11/29
EWR 70/1990
BDR 65/1968
NYC 69/1990
LGA 69/1990
JFK 64/1991
ISP 66/1991
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW YORK NY
721 PM EST SUN NOV 27 2011
.SYNOPSIS...
HIGH PRESSURE REMAINS OFFSHORE TO THE EAST MONDAY WHILE A LOW
PRESSURE SYSTEM TRACKS EAST ACROSS CANADA...DRAGGING A COLD FRONT
THROUGH NEW ENGLAND. A STORM SYSTEM WILL SLOWLY TRACK FROM THE UPPER
OHIO RIVER VALLEY TO THE CANADIAN MARITIME PROVINCES BY THURSDAY
MORNING. WEAK HIGH PRESSURE BUILDS IN THURSDAY AND THURSDAY
NIGHT...FOLLOWED BY A WEAK COLD FRONT ON FRIDAY. HIGH PRESSURE
THEN BUILDS IN FOR THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
WATER VAPOR SHOWS A DEEP LAYERED RIDGE...WITH THE RIDGE AXIS TO
OUR SW...AND GUIDANCE SUGGESTS THE STATUS QUO WILL MAINTAIN ITSELF
THROUGH TONIGHT. THE RESULT IS MINIMAL IF ANY FORCING...SO HAVE
REMOVED ALL PRECIPITATION FROM TONIGHT. UPDATED POPS ARE
CONSISTENT WITH A BLEND OF HRRR HOURLY AND SREF AND NAM 3-HOUR
POPS - WEIGHED MORE TOWARDS THE HRRR IN THE FIRST SIX HOURS OR SO.
STILL APPEAR ON TRACK FOR FOG OR STRATUS TO DEVELOP
TONIGHT. TYPICALLY YOU END UP WITH ONE OR THE OTHER IN THESE
SOUTHERLY FLOW CASES...AND NOT BOTH. QUESTION IS WILL THE FOG
BECOME DENSE OR...WILL ULTIMATELY LOW LEVEL STRATUS WIN OUT. FOR
NOW BEGINNING TO LEAN MORE TOWARDS THE STRATUS BASED ON BUFKIT
PROFILES...BUT NOT CONFIDENT ENOUGH TO REMOVE FOG FROM ZONES AT
THIS TIME. HOWEVER IF THE FOG WINDS OUT...WILL LIKE SEE DENSE
FOG...EVEN MORE WIDESPREAD THEN LAST NIGHT.
MINOR ADJUSTMENTS TO WINDS/DEWPOINTS/TEMPERATURES MADE BASED ON
LATEST TRENDS IN OBSERVATIONS AND 18Z GUIDANCE.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
THE LIGHT RAIN/DRIZZLE OVER FAR NW ZONES WILL REMAIN POSSIBLE
THROUGH AROUND 16Z BEFORE THINGS DRY UP FOR THE REST OF THE
PERIOD. HIGH PRESSURE REMAINS TO THE EAST...WITH TWO LOW PRESSURE
SYSTEMS BECOMING THE NEXT FOCUS. THE ONE LOW MOVING THROUGH CANADA
WILL DRAG A COLD FRONT THROUGH NORTHERN NEW ENGLAND. CURRENT
GUIDANCE INDICATES THE FRONT WILL REMAIN NORTH OF THE AREA...AND
THUS SHOULDN/T AFFECT THE CWA. THE SECOND LOW FORMS OVER THE
SOUTHEASTERN US MONDAY MORNING AND PUSHES NORTH THROUGH THE
DAY...SETTLING OVER TN AND KY FOR MON NIGHT. THE UPPER LEVEL RIDGE
WILL BEGIN WEAKENING AS WELL MONDAY...AHEAD OF A DEVELOPING UPPER
LEVEL LOW OVER THE MIDWEST.
SOUTHWESTERLY FLOW WILL PERSIST THROUGH MONDAY...WITH THE WINDS
SHIFTING BACK TO A SOUTHERLY FLOW FOR MON NIGHT. SIDED MORE WITH
A GFS/MOS MIX FOR GUIDANCE FOR WINDS DURING THIS PERIOD AS THE NAM
BRINGS THE WINDS AROUND TO THE EAST MUCH QUICKER...BY 12Z TUES
MORNING. CURRENT THINKING WILL BE THE LOW IS SLIGHTLY SLOWER...AND
THE WINDS WILL BE MORE SOUTHEASTERLY BY 12Z TUES MORNING. THE NAM
ALSO WANTS TO HAVE THE HIGH PRESSURE MORE DOMINANT MON NIGHT...SO
SIDED WITH THE WEAKER HIGH WITH THE GFS. WITH THE GFS
TIMING...BROUGHT IN A SLIGHT CHANCE FOR POPS LATE IN THE PERIOD MON
NIGHT FOR THE FAR WESTERN PORTION OF THE CWA. WITH THE LOWER LEVEL
MOISTURE REMAINING ELEVATED...HAVE ALSO INCLUDED PATCHY FOG AROUND
THE CWA FOR MON NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
GFS IN GENERAL TOO PROGRESSIVE AS HAS BEEN ITS BIAS OF LATE...SO
USED A NAM/ECMWF/SREF BLEND TUESDAY-WEDNESDAY...THEN FOLLOWED THE
ECMWF WEDNESDAY NIGHT-SUNDAY.
UPPER RIDGE AXIS OVER THE REGION SUPPORTS DAMMING HIGH SIGNATURE
OVER THE REGION TUESDAY INTO TUESDAY NIGHT. THIS WILL HELP TO SERVE
TO IMPEDE PROGRESS OF PRECIPITATION INTO THE REGION AHEAD OF CUTOFF
SYSTEM MOVING INTO THE WEST-CENTRAL APPALACHIANS BY TUESDAY EVENING.
AS A RESULT ONLY BRING POPS UP TO LIKELY OVER WESTERN 1/5 OF CWA AND
JUST BARELY TO CHANCE OVER FAR EASTERN PARTS OF THE CWA BY LATE
AFTERNOON.
STRONG ISENTROPIC LIFT DEVELOPS TUESDAY NIGHT...ALONG WITH 50-60 KT
LOW LEVEL JET IMPACTING REGION...ALLOWING FOR MODERATE TO POSSIBLY
LOCALLY HEAVY RAINFALL TO DEVELOP ACROSS THE TRI-STATE TUESDAY
NIGHT. WITH SHOWALTERS 0 TO -2...HAVE ADDED SLIGHT CHANCE OF THUNDER
TO ALL AREAS EAST OF THE HUDSON PLUS MOST OF NE NJ. CATEGORICAL POPS
THROUGHOUT TUESDAY NIGHT (DEVELOP FROM W TO E).
SHOWERS SHOULD TAPER OFF FROM W TO E MAINLY DURING WEDNESDAY
MORNING. THERE ARE SOME HINTS THAT FAR NW ZONES COULD END UP GETTING
SOME DEFORMATION AXIS PRECIPITATION WEDNESDAY AFTERNOON...BUT TOO
MUCH UNCERTAINTY TO REFLECT THIS IN FORECAST AT THIS TIME. COULD SEE
SOME GUSTY SW-W WINDS BEHIND THE COLD FRONT.
IMPROVING CONDITIONS WEDNESDAY NIGHT AS CLOSED LOW OPENS UP AND
PILLS TO THE NE...WITH WEAK RIDGING BEGINNING TO BUILD IN LATE.
SPLIT FLOW OVER THE EASTERN U.S. THURSDAY/THURSDAY NIGHT...WITH A
SOUTHERN STREAM TROUGH PASSING TO THE S...AND WEAK RIDGING OVER US
EVOLVING INTO SW FLOW ALOFT.
500 HPA TROUGH APPROACHES FRIDAY THEN CROSSES REGION FRIDAY NIGHT.
WITH LIMITED LOW LEVEL MOISTURE TO WORK WITH...GOING WITH A DRY
PASSAGE FOR NOW.
STRONG RIDGE RE-ESTABLISHES ITSELF OVER FLORIDA...WITH ITS RIDGE
AXIS PUSHING UP INTO THE NE STATES SATURDAY...THEN SLIDING OFFSHORE
SUNDAY. THIS SHOULD KEEP THE REGION DRY.
FOR TEMPERATURES...
FOR HIGHS TUESDAY...BLENDED MAV/MET GUIDANCE. HAVE SUSPICIONS THAT
THIS COULD ULTIMATELY END UP BEING ON THE WARM SIDE...WITH
TEMPERATURES STRUGGLING TO GET OUT OF THE 50S WITH THE TRI-STATE
BEING STUCK UNDER LOW CLOUDS/OCCASIONAL DRIZZLE DUE TO ONSHORE
FLOW...BUT STILL NEED TO SEE A FEW MORE THINGS WORK THEMSELVES OUT
BEFORE GOING THIS ROUTE.
FOR LOWS TUESDAY NIGHT...CONTINUED WITH MAV/MET BLEND...WEIGHING
TOWARDS WARMER GUIDANCE AS MAV TRIES TO COOL THINGS OFF TO MUCH AS
IT ENDS PRECIP TOO SOON.
FOR HIGHS WEDNESDAY USED A MEX/MEX ENSEMBLE MEAN BLEND...THEN
CONTINUED TO USE THIS...WITH HPC GUIDANCE BLENDED IN
THURSDAY-SUNDAY. MAIN PLACE HPC GUIDANCE CHANGED THINGS WAS NEXT
WEEKEND WHERE GFS SOLUTION IS NOTABLY COOLER THAN CURRENTLY
PREFERRED ECMWF SOLUTION.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE REMAINS EAST OF THE TERMINALS WITH A DEEP SOUTHERLY
FLOW. CONDITIONS START OFF AT VFR...HOWEVER STRATUS IS LIKELY TO
DEVELOP LATE THIS EVENING INTO THE OVERNIGHT...05Z TO 07Z...WITH
MVFR TO IFR CEILINGS. CONFIDENCE HIGHER FOR THE COASTAL
TERMINALS...THAN INLAND. VISIBILITIES IN FOG ARE LIKELY TO REMAIN
MVFR. CONFIDENCE FOR FOG DEVELOPMENT LOWER THAN FOR STRATUS.
IMPROVEMENT BACK TO VFR WILL OCCUR AROUND MID MORNING...13Z TO 15Z.
OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
MONDAY NIGHT...FOG AND STRATUS DEVELOPING WITH MVFR TO IFR
CONDITIONS.
TUESDAY-WEDNESDAY...PERIODS OF SUB-VFR CONDITIONS POSSIBLE IN
SHOWERS/FOG.
THURSDAY-FRIDAY...VFR.
&&
.MARINE...
DEVELOPING SOUTHERLY FLOW BRINGS POTENTIAL FOR LOW CLOUDS OR FOG
LATE TONIGHT INTO MONDAY MORNING. IF IT ENDS UP BEING FOG...COULD
END UP NEEDING DENSE FOG ADVISORIES...ESPECIALLY NEAR THE COAST.
SOUTHWESTERLY WINDS WILL PERSIST THROUGH TONIGHT INTO TOMORROW
BEFORE SHIFTING TO A SOUTHEASTERLY FLOW BY TUES MORNING. PRESSURE
GRADIENT IS EXPECTED TO RELAX A BIT TONIGHT...AS HIGH DRIFTS
FURTHER OFFSHORE AND A FRONTAL BOUNDARY REMAINS OVER THE SAINT
LAWRENCE RIVER VALLEY. THIS WILL ALLOW FOR WINDS TO GRADUALLY
DIMINISH OVERNIGHT. WAVEWATCH GUIDANCE BROUGHT 5 FT WAVES TO THE
EDGE OF THE MARINE ZONES...WHILE PRODUCING MAINLY 4 FT OVER THE
REST OF THE OCEAN WATER ZONES. HAVE OPTIONED TO NOT ISSUE A SCA
FOR WAVES FOR TONIGHT. AS THE WINDS CONTINUE TO WEAKEN
MONDAY...EXPECT THE SEAS TO SUBSIDE FOR THE DAY BEFORE INCREASING
AGAIN LATE MON NIGHT AS THE WINDS INCREASE WITH THE APPROACHING
LOW FROM THE SOUTH.
STRENGTHENING EASTERLY FLOW SHOULD BUILD AT LEAST SEAS TO SCA LEVELS
ON THE COASTAL OCEAN WATERS TUESDAY AFTERNOON...AND COULD QUITE
POSSIBLY RESULT IN GUSTS TO 25 KT ON ALL WATERS BY THEN AS WELL.
GUSTY WINDS CONTINUE TUESDAY NIGHT...THOUGH FEEL MARINE LAYER WILL
PREVENT BULK OF 45-55KT 950 HPA JET FROM MIXING DOWN...SO KEPT GUSTS
TO SCA LEVELS. WIND GUSTS TO SCA LEVELS SHOULD CONTINUE ON ALL
WATERS INTO WEDNESDAY EVENING...BUT SEAS SHOULD REMAIN AT SCA LEVELS
ON THE COASTAL OCEAN ZONES ALL NIGHT.
IT IS POSSIBLE THAT SCA LEVEL SEAS COULD PERSIST ON ANZ-350 ON
THURSDAY...OTHERWISE EXPECT SUB-SCA CONDITIONS ON ALL WATERS INTO
FRIDAY.
&&
.HYDROLOGY...
LIGHT RAIN IS POSSIBLE OVER THE HUDSON RIVER VALLEY TONIGHT...WITH
JUST A TRACE EXPECTED. DRY WEATHER WILL PERSIST THROUGH MONDAY FOR
THE REST OF THE CWA. THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL
FROM LATE TUESDAY INTO WEDNESDAY MORNING. FOR NOW FORECASTING
FROM AROUND 1/2 TO 3/4 AN INCH OF RAINFALL WITH LOCALLY HIGHER
AMOUNTS POSSIBLE. THIS MAKES MINOR URBAN/POOR DRAINAGE FLOODING
THE MOST LIKELY SCENARIO...ESPECIALLY IN AREAS RECEIVING LOCALLY
HEAVY RAINFALL DUE TO PASSING ELEVATED CONVECTION.
&&
.CLIMATE...
THE LATEST GUIDANCE INDICATES THAT HIGHS MONDAY WILL NOT REACH
RECORD HIGH TEMPS. HOWEVER...WITH TEMPS STILL FORECASTED IN THE
LOWER 60S...IT MAY STILL BE POSSIBLE FOR ISOLATED LOCATIONS IN AND
AROUND THE NEW YORK CITY METRO AREA TO COME CLOSE. RECORD HIGH
TEMPS WILL ALSO BE APPROACHED ON TUESDAY...WITH HIGHS ONCE AGAIN
BEING FORECASTED IN THE LOWER TO MID 60S.
FOR MONDAY 11/28
EWR 72/1973
BDR 65/2001
NYC *69/1990
LGA 68/1990
JFK 66/2001
ISP 66/1995
* ALSO OCCURRED IN PREVIOUS YEARS
FOR TUESDAY 11/29
EWR 70/1990
BDR 65/1968
NYC 69/1990
LGA 69/1990
JFK 64/1991
ISP 66/1991
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MALOIT/SEARS
NEAR TERM...MALOIT
SHORT TERM...SEARS
LONG TERM...MALOIT
AVIATION...MET
MARINE...MALOIT/SEARS
HYDROLOGY...SEARS
CLIMATE...SEARS/JCP
AREA FORECAST DISCUSSION
NWS DES MOINES IA
734 PM CST SUN NOV 27 2011
.UPDATE AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
PRIMARY CONCERN REMAINS LOW CLOUD TRENDS. MODELS HAVE HAD A POOR
TIME INITIALIZING AND RESOLVING STRATUS...BUT LATEST RUC SEEMS TO
HAVE THE BEST HANDLE ON THINGS BEING MORE PERSISTENT. THIS
GENERALLY AGREES WITH EXTRAPOLATION NUDGING CLEARING LINE SLOWLY
EASTWARD INTO CENTRAL IA TOWARD MIDNIGHT AND SUGGESTING CLEARING TO
OUR ERN FORECAST AREA BY MORNING BASED ON FURTHER EXTRAPOLATION.
LOW CONFIDENCE IN THESE TRENDS WILL ALSO SPILL OVER INTO MIN TEMPS.
HAVE GENERALLY FOLLOWED GUIDANCE WEST WHERE AIRMASS IS ADEQUATELY
REPRESENTED BY MODELS. HOWEVER NUDGED TEMPS UP ABOVE EVEN THE
WARMEST GUIDANCE EAST WHERE PROLONGED CLOUD COVER IS ANTICIPATED.
CLEARING PROGRESSION WILL MAKE ALL THE DIFFERENCE...SO EXPECT
CONSIDERABLE GRADIENT IN MIN TEMPS.
.LONG TERM /TONIGHT THROUGH SUNDAY/...
FAIRLY BENIGN MID/LONG RANGE WITH LITTLE IN THE WAY OF PRECIPITATION
CHANCES UNTIL THE NEXT WEEKEND. NEXT WEATHER SYSTEM TO IMPACT IOWA
WILL BE A POSITIVELY TILTED SHORTWAVE MOVING ONSHORE IN THE PACIFIC
NORTHWEST AT THIS TIME. THE BRUNT OF THE SHORTWAVE ENERGY
ASSOCIATED WITH THE WAVE WILL PASS TO THE EAST WELL NORTH OF IOWA.
THE SOUTHERN PART OF THE SHORTWAVE SHOULD MERGE WITH LARGE UPPER LOW
OVER THE OHIO VALLEY BY 18Z TUESDAY. THE COLD FRONT ASSOCIATED WITH
THE SHORTWAVE SHOULD CROSS IOWA MONDAY NIGHT. ONLY LIMITED FORCING
AND MOISTURE SHOULD KEEP THE SENSIBLE WEATHER IMPACT LIMITED TO
INCREASED WINDS...CLOUDS AND MODEST COOLING BUT NO PRECIPITATION.
ON MONDAY...THERE SHOULD BE VERY LITTLE BOUNDARY LAYER FLOW WITH THE
CENTER OF A WEAK SURFACE HIGH PRESSURE SYSTEM IN THE AREA. MODEL
SOUNDINGS SHOW A VERY STRONG INVERSION WITH MINIMAL MIXING.
THEREFORE...EXPECT COOL TEMPERATURES WITH LIGHT SURFACE WINDS.
FOR THURSDAY AND BEYOND INTO NEXT WEEKEND...THE GFS AND ECMWF ONCE
AGAIN DIVERGE IN THEIR SOLUTIONS OF THE WEATHER OVER THE UPPER
MIDWEST. THE ECMWF LIFTS OUT AND WEAKENS THE SOUTHWEST UNITED
STATES UPPER LOW INTO THE PLAINS BY NEXT SATURDAY EVENING. THIS
WILL BRING THE NEXT CHANCE OF PRECIPITATION TO IOWA. IT IS FAR TO
EARLY TO DETERMINE THE EXTENT OF THE PRECIPITATION CHANCES OR THE
PRECIPITATION TYPE. FOR NOW...INTRODUCED SMALL POPS SATURDAY NIGHT
INTO SUNDAY.
&&
.AVIATION...28/02Z
HAVE UPDATED CLEARING TIMES FOR TAF SITES. ST DECK HAS SLOWED
SOMEWHAT AND TIMING SUGGESTS LATER ARRIVAL FOR CLEARING AT KMCW...
KALO...AND KOTM. MINOR ADJUSTMENTS MADE TO WESTERN PORTION OF SHIELD.
/REV
.PREVIOUS AVIATION...28/00Z
MAIN CONCERN TONIGHT IS THE SHIELD OF LOW MVFR STRATUS. CURRENT
TRENDS HAVE THE DECKS EASTERLY MOVEMENT NEARLY COMING TO A
STANDSTILL NOW THAT SUNSET HAS ARRIVED. HAVE SLOWED THE PROGRESSION
EAST BY 2 HOURS WEST AND 4 HOURS EAST...WITH RENEWED OPTIMISM THAT
THE DECK WILL CLEAR THE EASTERN TAF SITES...KALO AND KOTM...CLOSER
TO 1200Z MONDAY MORNING. WITH BOUNDARY LAYER RH CONTINUING TO BE HIGH
WILL LEAVE LIGHT BR IN TAF FCST FOR NOW AND REEVALUATE AT 06Z
PACKAGE. LITTLE WEATHER MONDAY AS RIDGE PASSES OVERHEAD ALLOWING FOR
WEST WIND TO INCREASE WITH WARM FRONT PASSAGE AND FEW200 TO ENCROACH
ON FORECAST AREA WITH INCREASED WINDS ALOFT.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SMALL
AVIATION...REV
LONG TERM...JOHNSON
AREA FORECAST DISCUSSION
NWS DES MOINES IA
534 PM CST SUN NOV 27 2011
.UPDATE 28/00Z AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
PRIMARY CONCERN REMAINS LOW CLOUD TRENDS. MODELS HAVE HAD A POOR
TIME INITIALIZING AND RESOLVING STRATUS...BUT LATEST RUC SEEMS TO
HAVE THE BEST HANDLE ON THINGS BEING MORE PERSISTENT. THIS
GENERALLY AGREES WITH EXTRAPOLATION NUDGING CLEARING LINE SLOWLY
EASTWARD INTO CENTRAL IA TOWARD MIDNIGHT AND SUGGESTING CLEARING TO
OUR ERN FORECAST AREA BY MORNING BASED ON FURTHER EXTRAPOLATION.
LOW CONFIDENCE IN THESE TRENDS WILL ALSO SPILL OVER INTO MIN TEMPS.
HAVE GENERALLY FOLLOWED GUIDANCE WEST WHERE AIRMASS IS ADEQUATELY
REPRESENTED BY MODELS. HOWEVER NUDGED TEMPS UP ABOVE EVEN THE
WARMEST GUIDANCE EAST WHERE PROLONGED CLOUD COVER IS ANTICIPATED.
CLEARING PROGRESSION WILL MAKE ALL THE DIFFERENCE...SO EXPECT
CONSIDERABLE GRADIENT IN MIN TEMPS.
.LONG TERM /TONIGHT THROUGH SUNDAY/...
FAIRLY BENIGN MID/LONG RANGE WITH LITTLE IN THE WAY OF PRECIPITATION
CHANCES UNTIL THE NEXT WEEKEND. NEXT WEATHER SYSTEM TO IMPACT IOWA
WILL BE A POSITIVELY TILTED SHORTWAVE MOVING ONSHORE IN THE PACIFIC
NORTHWEST AT THIS TIME. THE BRUNT OF THE SHORTWAVE ENERGY
ASSOCIATED WITH THE WAVE WILL PASS TO THE EAST WELL NORTH OF IOWA.
THE SOUTHERN PART OF THE SHORTWAVE SHOULD MERGE WITH LARGE UPPER LOW
OVER THE OHIO VALLEY BY 18Z TUESDAY. THE COLD FRONT ASSOCIATED WITH
THE SHORTWAVE SHOULD CROSS IOWA MONDAY NIGHT. ONLY LIMITED FORCING
AND MOISTURE SHOULD KEEP THE SENSIBLE WEATHER IMPACT LIMITED TO
INCREASED WINDS...CLOUDS AND MODEST COOLING BUT NO PRECIPITATION.
ON MONDAY...THERE SHOULD BE VERY LITTLE BOUNDARY LAYER FLOW WITH THE
CENTER OF A WEAK SURFACE HIGH PRESSURE SYSTEM IN THE AREA. MODEL
SOUNDINGS SHOW A VERY STRONG INVERSION WITH MINIMAL MIXING.
THEREFORE...EXPECT COOL TEMPERATURES WITH LIGHT SURFACE WINDS.
FOR THURSDAY AND BEYOND INTO NEXT WEEKEND...THE GFS AND ECMWF ONCE
AGAIN DIVERGE IN THEIR SOLUTIONS OF THE WEATHER OVER THE UPPER
MIDWEST. THE ECMWF LIFTS OUT AND WEAKENS THE SOUTHWEST UNITED
STATES UPPER LOW INTO THE PLAINS BY NEXT SATURDAY EVENING. THIS
WILL BRING THE NEXT CHANCE OF PRECIPITATION TO IOWA. IT IS FAR TO
EARLY TO DETERMINE THE EXTENT OF THE PRECIPITATION CHANCES OR THE
PRECIPITATION TYPE. FOR NOW...INTRODUCED SMALL POPS SATURDAY NIGHT
INTO SUNDAY.
&&
.AVIATION...28/00Z
MAIN CONCERN TONIGHT IS THE SHIELD OF LOW MVFR STRATUS. CURRENT
TRENDS HAVE THE DECKS EASTERLY MOVEMENT NEARLY COMING TO A
STANDSTILL NOW THAT SUNSET HAS ARRIVED. HAVE SLOWED THE PROGRESSION
EAST BY 2 HOURS WEST AND 4 HOURS EAST...WITH RENEWED OPTIMISM THAT
THE DECK WILL CLEAR THE EASTERN TAF SITES...KALO AND KOTM...CLOSER
TO 1200Z MONDAY MORNING. WITH BOUNDARY LAYER RH CONTINUING TO BE HIGH
WILL LEAVE LIGHT BR IN TAF FCST FOR NOW AND REEVALUATE AT 06Z
PACKAGE. LITTLE WEATHER MONDAY AS RIDGE PASSES OVERHEAD ALLOWING FOR
WEST WIND TO INCREASE WITH WARM FRONT PASSAGE AND FEW200 TO ENCROACH
ON FORECAST AREA WITH INCREASED WINDS ALOFT.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SMALL
AVIATION...REV
LONG TERM...JOHNSON
AREA FORECAST DISCUSSION...CORRECTED WATCH/WARNING/ADVISORY CODING
NWS DES MOINES IA
320 PM CST SAT NOV 26 2011
.SHORT TERM /TONIGHT/...
MAIN CONCERN TONIGHT WILL BE TEMP AND WIND TRENDS...AND PRECIP TO A
LESSER EXTENT. PRIMARY PRECIP SHIELD ASSOCIATED WITH CENTRAL CONUS
LONG WAVE TROUGH CURRENTLY EXTENDS FROM SRN PLAINS INTO GREAT LAKES
AND HAS ALL BUT EXITED FORECAST AREA. FORCING WITH THIS IS MAINLY
MID/UPPER LEVEL BASED IN THE FORM OF DPVA AND RIGHT ENTRANCE REGION
DIVERGENCE OF GREAT LAKES JET SEGMENT. RADAR AND SATELLITE TRENDS
DO NOT LOOK PROMISING FOR ADDITIONAL PRECIP THIS EVENING...HOWEVER
MODELS DO SUSTAIN SOME MID LEVEL KINEMATIC FORCING WITH BRIEF SURGE
OF DEEPER MOISTURE SWINGING THROUGH AROUND 00Z OR SHORTLY
THEREAFTER. THUS HAVE KEPT MENTION OF SPRINKLES OR FLURRIES NE
THIRD DURING THE EVENING.
POTENTIAL FOR ADVISORY LEVEL WINDS HAS DECREASED AS WELL...BOTH
SPATIALLY AND TEMPORALLY...WITH ONLY A SITE OR TWO WEST CURRENTLY
VERIFYING. ISALLOBARIC MAX...MAX MSLP GRADIENT...AND MAGNITUDE OF
MIXED LAYER WINDS ALL DECREASE THIS EVENING AS THEY APPROACH THE MO
RIVER SO DO NOT EXPECT ADVISORY CRITERIA WINDS TO CONTINUE AS LONG
OR AS FAR EAST AS PREVIOUSLY ANTICIPATED. THUS HEADLINE NOW ENDS AT
03Z WITH SEVERAL TIERS OF ERN COUNTIES REMOVED.
OUTSIDE OF THE RUC...RAW MODEL TEMPS ARE BEHIND THE CURVE IN TERMS
OF COOLING. HOWEVER EVEN THE COOLER NAM WHICH EVENTUALLY CATCHES UP
TO THE RUC SUGGESTS CLOUDS AND WINDS KEEPING TEMPS ABOVE GUIDANCE.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
IN THE LONG TERM...IT WILL BE FAIRLY QUIET WITH A DRY FORECAST
THROUGH DAY SEVEN. UPPER LEVEL LOW PRESSURE SYSTEM FORECAST BY ALL
MODELS OVER THE SOUTHEAST UNITED STATES HEADS NORTH INTO THE OHIO
VALLEY BY TUESDAY. MEANWHILE...A WEAK NORTHERN STREAM SHORTWAVE
SHOULD CROSS THE NORTHERN PLAINS AND UPPER MIDWEST. UPSTREAM QG
FORCING OVER THE NORTHERN PLAINS SHOULD WEAKEN AS THE WAVE
APPROACHES THE MISSISSIPPI VALLEY AND INTERACTS WITH UPPER LOW
MOVING NORTH INTO THE OHIO VALLEY. THE LACK OF SUSTAINED VERTICAL
MOTION AND LIMITED MOISTURE SHOULD KEEP THE ASSOCIATED COLD FRONT
DRY WITH SOME CLOUDS AS IT CROSSES IOWA. ON MONDAY...AHEAD OF THE
FRONT...WEAK HIGH PRESSURE OVER CENTRAL IOWA BETWEEN THE SYSTEM OVER
THE OHIO VALLEY AND THE APPROACHING COLD FRONT. ONLY MODEST MIXING
SHOULD KEEP TEMPERATURES RELATIVELY COOL CONSIDERING THE THERMAL
CHARACTERISTICS OF THE AIRMASS. GIVEN THE EXPECTED COOL TEMPERATURES
ON MONDAY...ONLY MODEST COOLING IS FORECAST BEHIND THE FRONT ON
TUESDAY. THIS IS PROBABLY DUE TO BETTER MIXING EVEN THOUGH THE
AIRMASS WILL BE COOLER.
MODELS AGREE IN DIGGING AN UPPER LOW OVER THE SOUTHWEST UNITED
STATES DURING THE EXTENDED. THE 12Z ECMWF/GFS SUGGEST NORTHWEST
FLOW OVER THE NORTH CENTRAL UNITED STATES BUT THEY HAVE TIMING
DIFFERENCES WITH SHORTWAVES AND FRONTAL PASSAGES LATE NEXT WEEK.
ALTHOUGH ALL SOLUTIONS LOOK MAINLY DRY FOR CENTRAL IOWA...DAY TO DAY
TEMPERATURE FORECASTS HAVE ONLY MODEST CONFIDENCE AT THIS POINT.
&&
.AVIATION...26/18Z
IFR STRATUS FOLLOWING COLD FRONT CROSSING MS RIVER AT 18Z WILL EXIT
KMCW/KOTM SHORTLY. WIDESPREAD MVFR CIGS FOLLOW CLOSE BEHIND AND
WILL ENCOMPASS MUCH OF STATE THIS AFTERNOON. CIGS ARE CURRENTLY SUB
2KFT BUT MAY RAISE ABOVE THAT THIS AFTERNOON BEFORE DROPPING BACK
BELOW AGAIN OVERNIGHT. PEAK WIND GUSTS WILL OCCUR THIS EVENING AS
MIXING PERSISTS AND APPROACH OF MSLP GRADIENT AND ISALLOBARIC
COMPONENT MAXES. CIGS MAY DISSIPATE OVER WRN IA LATE...VFR POSSIBLY
REACHING KFOD.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR
AUDUBON-CALHOUN-CARROLL-CASS-CRAWFORD-EMMET-PALO ALTO-POCAHONTAS-SAC.
&&
$$
SHORT TERM...SMALL
LONG TERM...JOHNSON
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1132 AM CST SAT NOV 26 2011
.AVIATION...
FOR THE 18Z TAF ISSUANCE...
VERY STRONG WINDS OF 35 KNOTS ARE EXPECTED TO PERSIST THROUGH THE
MID TO LATE AFTERNOON HOURS...UNTIL DEEP ATMOSPHERIC MIXING
SUBSIDES WITH LOWER SUN ANGLE. WILL DECREASE SUSTAINED WINDS IN
THE TAFS AT 22Z TO 26 KNOTS GUSTING TO LOWER 30S KNOTS...THEN
DECREASE WINDS FURTHER TO 16 KNOTS SUSTAINED AT 02Z WHEN PRESSURE GRADIENT
RELAXES AND THERE IS NO LONGER INSOLATION TO KEEP THE LOWER
ATMOSPHERE MIXED. THE SKY WILL BE CLEAR AS THE STORM SYSTEM
CONTINUES TO MOVE AWAY FROM KANSAS. -UMSCHEID
&&
PREV DISCUSSION... /ISSUED 309 AM CST SAT NOV 26 2011/
SYNOPSIS...
UPPER AIR ANALYSIS SHOWS THAT A LARGE TROF IS MOVING ACROSS THE
PLAINS THIS MORNING. THIS FEATURE CAUSED THE PRECIPITATION EVENT
THAT OCCURRED LAST NIGHT AND BROUGHT THE WELCOMED RAINS. A COLD
FRONT WAS PUSHING INTO WESTERN KANSAS EARLY THIS MORNING AND WILL
BE THE MAIN IMPACT TODAY IN TERMS OF WEATHER.
DISCUSSION...
DAYS 1-2...
IMMEDIATE CONCERN IS THE PRECIPITATION MOVING OUT OF THE AREA. KDDC
WSR-88D SHOWS THAT THE PRECIPITATION SHIELD IS SLOWLY MOVING OUT
OF THE CWFA AND HAVE TAPERED POPS DOWN AS A RESULT. I HAVE 15 PERCENT
POPS NORTH WHERE THE GFS AND THE RUC ARE INDICATING THE POTENTIAL FOR
A FEW SPRINKLES OR FLURRIES.
THE OTHER FOCUS TODAY IS WIND. 1 KM WINDS ARE AROUND 50 KT WITH 850
HPA WINDS IN THE 45 TO 55 KT RANGE. A FRONT IS MOVING ACROSS WESTERN
KANSAS EARLY THIS MORNING WITH STRONG WINDS ALREADY BEING REPORTED ACROSS
THE HIGH PLAINS OF EASTERN COLORADO. THE MOST RECENT HRRR SHOWS 10M
WINDS AROUND 35 KT THROUGH THIS AFTERNOON. AS A RESULT, HAVE ISSUED
A HIGH WIND WARNING FOR POINTS WEST OF A LINE FROM TREGO TO CLARK
COUNTIES. FURTHER EAST TOWARDS HAYS, THE MOS GUIDANCE IS MORE
MARGINAL SO HAVE DECIDED TO KEEP THE AREA EAST OF A LINE FROM ELLIS
TO COMANCHE COUNTIES IN A WIND ADVISORY. FURTHER WEST, MOS GUIDANCE
WAS SUPPORTING WIND WARNING CRITERIA WITH FORECAST OF 40G50KT AT
GARDEN CITY AND LIBERAL. SINCE WE WILL HAVE A NORTHWESTERLY
DOWNSLOPE COMPONENT, I INCREASED TEMPERATURES A DEGREE OR TWO ABOVE
GUIDANCE. TEMPERATURES SHOULD WARM TO THE UPPER 40S TO LOWER 50S.
THE FIRE WEATHER WATCH WAS ALSO CANCELLED AS RH`S NOW LOOK LIKE TO NOT
MEET THE 15 PERCENT CRITERIA. FOR MORE INFORMATION, SEE THE FIRE WEATHER
AFD SECTION BELOW.
BY TONIGHT, WE WILL HAVE NORTHERLY FLOW ALOFT IN THE WAKE OF THE UPPER
LEVEL TROF. SKIES SHOULD CLEAR AS DRY AIR ADVECTION STARTS THROUGH THE
ATMOSPHERIC COLUMN SO AM EXPECTING COOLER OVERNIGHT LOWS...GENERALLY IN
THE 20S.
THE WEATHER WILL STILL BE QUIET SUNDAY AS 500 HPA HEIGHTS INCREASE IN
RESPONSE TO RIDGING ACROSS THE DESERT SOUTHWEST. POPS WILL REMAIN
AT ZERO. MAX TEMPERATURES ARE EXPECTED IN THE 50S WHICH IS SLIGHTLY
ABOVE NORMAL.
DAYS 3-7...
THE 00Z RUNS OF THE MEDIUM RANGE MODELS HAVE COME INTO BETTER
AGREEMENT IN HANDLING THE UPPER TROUGH THAT IS CURRENTLY MOVING OUT
INTO THE CENTRAL CONUS. THE GFS HAS TRENDED TOWARD THE OTHER MODELS
IN THAT IT IS NOW CLOSING OFF AN UPPER LOW OVER THE LOWER
MISSISSIPPI VALLEY SIMILAR TO...BUT NOT AS FAR SOUTH...AS THE ECMWF.
ANY SENSIBLE WEATHER IMPACTS FROM THIS WILL BE WELL TO THE EAST OF
WESTERN KANSAS. THE MODELS CONTINUE TO SHOW THE NEXT STRONG
SHORTWAVE TROUGH MOVING EAST THROUGH THE NORTHERN CONUS WITH SOME
SHORTWAVE ENERGY MOVING SOUTHEAST OVER THE CENTRAL HIGH PLAINS.
ANOTHER STRONG COLD FRONT WILL PUSH SOUTH THROUGH WESTERN KANSAS LATE
MONDAY AFTERNOON AND EVENING. THE MODELS ARE NOT INDICATING MUCH IN
THE WAY OF PRECIPITATION WITH THIS FRONT. THIS LOOKS REASONABLE
GIVEN THAT LOW LEVEL MOISTURE WILL NOT HAVE AN OPPORTUNITY TO RETURN
NORTHWARD IN THE WAKE OF TODAYS UPPER TROUGH. THERE COULD BE A
PERIOD OF STRONG WINDS BEHIND THE FRONT AS AT LEAST THE GFS IS
SHOWING 850 MB WINDS TO 50 KNOTS.
THE MIDDLE PART OF NEXT WEEK SHOULD BE FAIRLY QUIET AS UPPER LEVEL
RIDGING MOVES OVER THE CENTRAL PLAINS. HOWEVER...ANOTHER UPPER
TROUGH WILL BE DIGGING SOUTH INTO THE WESTERN STATES. THE MODELS ARE
DIFFERING IN SOMEWHAT IN HOW THIS SYSTEM DEVELOPS BUT THEY ALL
DEVELOP IT INTO A CLOSED LOW OVER SOUTHERN CALIFORNIA/ARIZONA BY
NEXT FRIDAY. THE MODELS BRING ANOTHER COLD FRONT WITH MUCH COOLER
AIR SOUTH ACROSS WESTERN KANSAS AROUND THURSDAY OR FRIDAY AND THEN
MOVE THE UPPER LOW EAST TOWARD THE CENTRAL AND SOUTHERN PLAINS NEXT
WEEKEND. THIS COULD HAVE SOME SIGNIFICANT WEATHER IMPACTS WITH THE
POSSIBILITY FOR A SNOWSTORM ACROSS SOUTHWEST KANSAS NEXT WEEKEND
DEPENDING ON THE TRACK OF THE UPPER LOW.
FIRE WEATHER...
HAVE CANCELLED THE FIRE WEATHER WATCH AS UPSTREAM DEWPOINT OBSERVATIONS
ARE SHOWING THAT THE MODEL DEWPOINTS ARE RUNNING A LITTLE LOW. EVEN
WARMING UP TEMPERATURES AND ARTIFICIALLY LOWERING DEWPOINTS ONLY PRODUCES
RH`S IN THE 20 TO 30 PERCENT RANGE. WINDS WILL BE STRONG TODAY THOUGH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 46 25 54 31 / 0 0 0 0
GCK 45 23 55 31 / 0 0 0 0
EHA 44 23 58 35 / 0 0 0 0
LBL 46 23 56 32 / 0 0 0 0
HYS 47 24 52 30 / 0 0 0 0
P28 49 27 53 30 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 6 PM CST /5 PM MST/ THIS EVENING FOR
KSZ030-043>045-061>064-074>078-084>088.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR KSZ031-046-065-066-
079>081-089-090.
&&
$$
FN99/99/25
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1004 AM MST SAT NOV 26 2011
.SHORT TERM (TODAY-MONDAY)...
240 AM MST SAT NOV 26 2011
EARLY MORNING WV IMAGERY AND RUC H5 ANALYSIS SHOW AMPLIFIED
RIDGE-TROUGH-RIDGE PATTERN OVER THE CONUS...WITH MEAN TROUGH AXIS
CENTERED ALONG CO/KS STATE LINE. AT THE SURFACE COLD FRONT CURRENTLY
SOUTHEAST OF CWA...WITH SURFACE HIGH PRESSURE QUICKLY BUILDING IN
BEHIND FRONT OVER CWA. UPSTREAM 3HR PRESSURE RISES AROUND 7MB HAVE
BEEN OBSERVED OVER PARTS OF EASTERN WYOMING/WESTERN NEBRASKA...WITH
3-5MB PRESSURE RISES OVER WESTERN PARTS OF CWA. VAD WIND PROFILER
DATA SHOWS 45-55KT LOW LEVEL JET OVERHEAD...WITH LOCAL OBSERVATIONS
REPORTING SURFACE WINDS GUSTING 45-48KT.
IMMEDIATE FORECAST CONCERNS IN THE SHORT RANGE ARE ON PRECIP CHANCES
EARLY THIS MORNING AND HIGH WINDS THROUGH THIS AFTERNOON.
RIGHT ENTRANCE REGION OF H25-H3 JET COMBINED WITH STEEP MID LEVEL
LAPSE RATES HAVE LED TO DEVELOPMENT ON SCT-ISO SHOWERS OVER NE
COLORADO...WHICH HAS PROGRESSED EAST INTO SW NEBRASKA AND EXTREME NW
KANSAS EARLY THIS MORNING. AS CAA CONTINUES EXPECT MOST LOCATION TO
SEE SNOW BECOME PREDOMINANT PRECIP TYPE. WEAK MOISTURE ADVECTION
COMBINED WITH BUILDING SUBSIDENCE ALOFT SHOULD LIMIT PRECIP
AMOUNTS...SO ONLY EXPECTING LOCALIZED SNOW TOTALS OF LESS THAN ONE
HALF INCH...WHILE MOST LOCATIONS WILL STRUGGLE TO SEE EVEN A FEW
TENTHS OF AN INCH DUE TO MELTING. GUIDANCE SNOWS STRONG SUBSIDENCE
OVERTAKING AREA BY 12Z ALONG WITH VERY DRY AIR ADVECTING IN OVER THE
AREA...WHICH SHOULD END PRECIP CHANCES. WILL KEEP FORECAST DRY AFTER
12Z FOR NOW AND ADJUST BASED ON TRENDS.
WIND FORECAST IS CURRENTLY ON TRACK...WITH WIND GUSTS EARLY THIS
MORNING ALREADY ON HIGH END OF WIND ADVISORY OVER MOST THE AREA. RUC
CURRENTLY HAS BEST HANDLE ON H85-H7 WINDS BASED ON PROFILER
DATA...AND SHOWS 50KT H85 JET SPREADING EAST OVER REMAINING CWA.
WHILE PEAK PRESSURE RISES OCCUR BEFORE 12Z THIS MORNING...PERSISTENT
50KT H85 JET AND INCREASED MIXING AFTER SUNRISE SHOULD SUPPORT WINDS
INCREASING TO WARNING CRITERIA. THE STRONGEST SURFACE WINDS SHOULD
THEN DECREASE TOWARDS 00Z AS MIXING DECREASES AND WINDS ALOFT BEGIN
TO SLACKEN.
TONIGHT-MONDAY NIGHT...H5 RIDGE BUILDS EAST AND STRENGTHENS OVER SW
CONUS...WITH SHORTWAVE RIDGE AXIS EXTENDING NORTH ACROSS CWA BY MON
NIGHT. LARGE SCALE SUBSIDENCE AND DEEP DRY AIR MASS OVER CWA WILL
HELP KEEP CONDITIONS DRY THROUGH THESE PERIODS WITH TEMPS WARMING TO
ABOUT 10-15F ABOVE NORMAL SUN/MON. TEMPS A LITTLE TRICKY ON MON AS
SHORTWAVE AND ASSOCIATED COLD FRONT MOVES ACROSS REGION. GUIDANCE
CONTINUING TO DIFFER ON POSITION/TIMING OF FRONT...WHICH WILL IMPACT
HIGH TEMPS MON ALONG WITH GUSTY WINDS MON AFTERNOON. FOR NOW HAVE
KEPT IN LINE WITH PREVIOUS FORECAST OF UPPER 50S NORTH/LOW 60S
SOUTH...HOWEVER TEMPS MAY END UP NEEDING TO BE LOWERED IF FASTER
FRONTAL TIMING OF SREF/GEM WERE TO BE REALIZED.
DR
.LONG TERM (TUESDAY-FRIDAY)...
240 AM MST SAT NOV 26 2011
AN UPPER LEVEL RIDGE WILL BUILD INTO THE TRI-STATE AREA THROUGH
THURSDAY. MODELS THEN BEGIN TO DISAGREE AS TO HOW QUICKLY THE
UPPER LEVEL RIDGE MOVES EAST AS THE UPPER LEVEL TROUGH BUILDS IN AND
WHEN THE COLD FRONT WILL MOVE THROUGH THURSDAY. AS A RESULT
HIGH TEMPERATURES FOR THURSDAY VARY SIGNIFICANTLY BETWEEN THE
MODELS. FRONTAL TIMING WILL ALSO AFFECT THE ARRIVAL AND TYPE OF
PRECIPITATION. CURRENT CONSENSUS HAS THE PRECIP. OCCURRING DURING
THE DAY FOR MOST OF THE CWA. DIFFICULT TO NAIL DOWN PRECIP. TYPE
THURSDAY DUE TO THE DIFFERENCE IN FRONTAL TIMING. GENERALLY HAVE
SNOW IN THE NORTHWEST AND FAR NORTH CWA WHICH TRANSITIONS TO A
NARROW BAND OF RAIN-SNOW MIX FOLLOWED BY RAIN FURTHER SOUTH. BEHIND
THE FRONT THE 850MB WINDS WILL BE GUSTY. HOWEVER MODELS DISAGREE
WITH THE TIMING AND PLACEMENT OF THE WINDS BEHIND THE FRONT...BUT
CONSENSUS HAS BREEZY CONDITIONS THURSDAY AFTERNOON. AFTER THURSDAY
THE UPPER LEVEL FLOW TURNS TO THE SOUTHWEST AND THE ENVIRONMENT
DRIES OUT. HOWEVER TEMPERATURES WILL REMAIN COOL AFTER THURSDAY AS
THE UPPER LEVEL TROUGH MOVES TOWARD THE AREA.
JTL
&&
.AVIATION...
1004 AM MST SAT NOV 26 2011
FOR THE 18Z TAFS...VFR CONDS WILL PREVAIL. WINDS WILL BE THE MAIN
CONCERN THROUGH THE SHORT TERM...GUSTING IN THE 40-50 KNOT RANGE AT
BOTH LOCATIONS FROM THE NORTHWEST THROUGH SUNSET. AFTER SUNSET AND
MIXING CEASES...WINDS WILL DIMINISH CONSIDERABLY. SKIES WILL BE
CLEAR THROUGH THE PERIOD AS HIGH PRESSURE BUILDS INTO THE AREA.
BAS
&&
.FIRE WEATHER...
240 AM MST SAT NOV 26 2011
RED FLAG WARNING CURRENTLY IN EFFECT FOR THIS AFTERNOON ACROSS
CWA. TD VALUES HAVE BEEN SLOWER TO DECREASE THAN PREVIOUS GUIDANCE
INDICATED...HOWEVER FINALLY BEGINNING TO SEE 10-15F TD VALUES
ADVECTING INTO EASTERN COLORADO. SINGLE DIGIT TD VALUES OVER
WYOMING SHOULD EVENTUALLY ADVECT OVER CWA...AND DESPITE AFTERNOON
TEMPS IN THE UPPER 30S/LOW 40S...CURRENTLY THINK RH VALUES 18-25%
SEEM REASONABLE. COMBINED WITH VERY STRONG WINDS THIS
AFTERNOON...CRITICAL FIRE CONDITIONS WILL CONTINUE TO BE A
CONCERN...SO NO CHANGES PLANNED FOR CURRENT HIGHLIGHT.
CRITICAL FIRE CONDITIONS WILL BE POSSIBLE AGAIN MONDAY AFTERNOON.
TIMING OF STRONGEST WINDS AND LOCATION OF LOWEST TD VALUES WILL
LIKELY BE DEPENDENT ON TIMING OF COLD FRONT...WHICH GUIDANCE IS
CURRENTLY DOING A POOR JOB OF TIMING OUT...SO WILL NEED TO MONITOR
THIS.
DR
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ001>004-013>016-027>029-041-042.
RED FLAG WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ001>004-013>016-027>029-041-042.
NE...HIGH WIND WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
NEZ079>081.
RED FLAG WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
NEZ079>081.
CO...HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ090>092.
RED FLAG WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ252>254.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
448 AM MST SAT NOV 26 2011
.SHORT TERM (TODAY-MONDAY)...
240 AM MST SAT NOV 26 2011
EARLY MORNING WV IMAGERY AND RUC H5 ANALYSIS SHOW AMPLIFIED
RIDGE-TROUGH-RIDGE PATTERN OVER THE CONUS...WITH MEAN TROUGH AXIS
CENTERED ALONG CO/KS STATE LINE. AT THE SURFACE COLD FRONT CURRENTLY
SOUTHEAST OF CWA...WITH SURFACE HIGH PRESSURE QUICKLY BUILDING IN
BEHIND FRONT OVER CWA. UPSTREAM 3HR PRESSURE RISES AROUND 7MB HAVE
BEEN OBSERVED OVER PARTS OF EASTERN WYOMING/WESTERN NEBRASKA...WITH
3-5MB PRESSURE RISES OVER WESTERN PARTS OF CWA. VAD WIND PROFILER
DATA SHOWS 45-55KT LOW LEVEL JET OVERHEAD...WITH LOCAL OBSERVATIONS
REPORTING SURFACE WINDS GUSTING 45-48KT.
IMMEDIATE FORECAST CONCERNS IN THE SHORT RANGE ARE ON PRECIP CHANCES
EARLY THIS MORNING AND HIGH WINDS THROUGH THIS AFTERNOON.
RIGHT ENTRANCE REGION OF H25-H3 JET COMBINED WITH STEEP MID LEVEL
LAPSE RATES HAVE LED TO DEVELOPMENT ON SCT-ISO SHOWERS OVER NE
COLORADO...WHICH HAS PROGRESSED EAST INTO SW NEBRASKA AND EXTREME NW
KANSAS EARLY THIS MORNING. AS CAA CONTINUES EXPECT MOST LOCATION TO
SEE SNOW BECOME PREDOMINANT PRECIP TYPE. WEAK MOISTURE ADVECTION
COMBINED WITH BUILDING SUBSIDENCE ALOFT SHOULD LIMIT PRECIP
AMOUNTS...SO ONLY EXPECTING LOCALIZED SNOW TOTALS OF LESS THAN ONE
HALF INCH...WHILE MOST LOCATIONS WILL STRUGGLE TO SEE EVEN A FEW
TENTHS OF AN INCH DUE TO MELTING. GUIDANCE SNOWS STRONG SUBSIDENCE
OVERTAKING AREA BY 12Z ALONG WITH VERY DRY AIR ADVECTING IN OVER THE
AREA...WHICH SHOULD END PRECIP CHANCES. WILL KEEP FORECAST DRY AFTER
12Z FOR NOW AND ADJUST BASED ON TRENDS.
WIND FORECAST IS CURRENTLY ON TRACK...WITH WIND GUSTS EARLY THIS
MORNING ALREADY ON HIGH END OF WIND ADVISORY OVER MOST THE AREA. RUC
CURRENTLY HAS BEST HANDLE ON H85-H7 WINDS BASED ON PROFILER
DATA...AND SHOWS 50KT H85 JET SPREADING EAST OVER REMAINING CWA.
WHILE PEAK PRESSURE RISES OCCUR BEFORE 12Z THIS MORNING...PERSISTENT
50KT H85 JET AND INCREASED MIXING AFTER SUNRISE SHOULD SUPPORT WINDS
INCREASING TO WARNING CRITERIA. THE STRONGEST SURFACE WINDS SHOULD
THEN DECREASE TOWARDS 00Z AS MIXING DECREASES AND WINDS ALOFT BEGIN
TO SLACKEN.
TONIGHT-MONDAY NIGHT...H5 RIDGE BUILDS EAST AND STRENGTHENS OVER SW
CONUS...WITH SHORTWAVE RIDGE AXIS EXTENDING NORTH ACROSS CWA BY MON
NIGHT. LARGE SCALE SUBSIDENCE AND DEEP DRY AIR MASS OVER CWA WILL
HELP KEEP CONDITIONS DRY THROUGH THESE PERIODS WITH TEMPS WARMING TO
ABOUT 10-15F ABOVE NORMAL SUN/MON. TEMPS A LITTLE TRICKY ON MON AS
SHORTWAVE AND ASSOCIATED COLD FRONT MOVES ACROSS REGION. GUIDANCE
CONTINUING TO DIFFER ON POSITION/TIMING OF FRONT...WHICH WILL IMPACT
HIGH TEMPS MON ALONG WITH GUSTY WINDS MON AFTERNOON. FOR NOW HAVE
KEPT IN LINE WITH PREVIOUS FORECAST OF UPPER 50S NORTH/LOW 60S
SOUTH...HOWEVER TEMPS MAY END UP NEEDING TO BE LOWERED IF FASTER
FRONTAL TIMING OF SREF/GEM WERE TO BE REALIZED.
DR
.LONG TERM (TUESDAY-FRIDAY)...
240 AM MST SAT NOV 26 2011
AN UPPER LEVEL RIDGE WILL BUILD INTO THE TRI-STATE AREA THROUGH
THURSDAY. MODELS THEN BEGIN TO DISAGREE AS TO HOW QUICKLY THE
UPPER LEVEL RIDGE MOVES EAST AS THE UPPER LEVEL TROUGH BUILDS IN AND
WHEN THE COLD FRONT WILL MOVE THROUGH THURSDAY. AS A RESULT
HIGH TEMPERATURES FOR THURSDAY VARY SIGNIFICANTLY BETWEEN THE
MODELS. FRONTAL TIMING WILL ALSO AFFECT THE ARRIVAL AND TYPE OF
PRECIPITATION. CURRENT CONSENSUS HAS THE PRECIP. OCCURRING DURING
THE DAY FOR MOST OF THE CWA. DIFFICULT TO NAIL DOWN PRECIP. TYPE
THURSDAY DUE TO THE DIFFERENCE IN FRONTAL TIMING. GENERALLY HAVE
SNOW IN THE NORTHWEST AND FAR NORTH CWA WHICH TRANSITIONS TO A
NARROW BAND OF RAIN-SNOW MIX FOLLOWED BY RAIN FURTHER SOUTH. BEHIND
THE FRONT THE 850MB WINDS WILL BE GUSTY. HOWEVER MODELS DISAGREE
WITH THE TIMING AND PLACEMENT OF THE WINDS BEHIND THE FRONT...BUT
CONSENSUS HAS BREEZY CONDITIONS THURSDAY AFTERNOON. AFTER THURSDAY
THE UPPER LEVEL FLOW TURNS TO THE SOUTHWEST AND THE ENVIRONMENT
DRIES OUT. HOWEVER TEMPERATURES WILL REMAIN COOL AFTER THURSDAY AS
THE UPPER LEVEL TROUGH MOVES TOWARD THE AREA.
JTL
&&
.AVIATION...
418 AM MST SAT NOV 26 2011
VFR CONDITIONS FOR THE 12Z TAFS. CURRENT RADAR AND UPPER AIR
ANALYSIS SHOW THE PRECIPITATION MOVING EAST AHEAD OF THE UPPER
LEVEL TROUGH. AS THE UPPER LEVEL TROUGH MOVES THROUGH THE
PRECIPITATION WILL COME TO AN END AND CEILINGS WILL INCREASE.
DURING THE DAY STRONG UPPER LEVEL WINDS WILL LIE OVER THE TAF
SITES. THE WARMER TEMPERATURES WILL ALLOW THE STRONG WINDS TO MIX
DOWN TO THE SURFACE. WINDS WILL REACH THEIR PEAK DURING THE MID
MORNING BEFORE DISSIPATING DURING THE LATE AFTERNOON.
JTL
&&
.FIRE WEATHER...
240 AM MST SAT NOV 26 2011
RED FLAG WARNING CURRENTLY IN EFFECT FOR THIS AFTERNOON ACROSS
CWA. TD VALUES HAVE BEEN SLOWER TO DECREASE THAN PREVIOUS GUIDANCE
INDICATED...HOWEVER FINALLY BEGINNING TO SEE 10-15F TD VALUES
ADVECTING INTO EASTERN COLORADO. SINGLE DIGIT TD VALUES OVER
WYOMING SHOULD EVENTUALLY ADVECT OVER CWA...AND DESPITE AFTERNOON
TEMPS IN THE UPPER 30S/LOW 40S...CURRENTLY THINK RH VALUES 18-25%
SEEM REASONABLE. COMBINED WITH VERY STRONG WINDS THIS
AFTERNOON...CRITICAL FIRE CONDITIONS WILL CONTINUE TO BE A
CONCERN...SO NO CHANGES PLANNED FOR CURRENT HIGHLIGHT.
CRITICAL FIRE CONDITIONS WILL BE POSSIBLE AGAIN MONDAY AFTERNOON.
TIMING OF STRONGEST WINDS AND LOCATION OF LOWEST TD VALUES WILL
LIKELY BE DEPENDENT ON TIMING OF COLD FRONT...WHICH GUIDANCE IS
CURRENTLY DOING A POOR JOB OF TIMING OUT...SO WILL NEED TO MONITOR
THIS.
DR
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ001>004-013>016-027>029-041-042.
RED FLAG WARNING FROM 11 AM MST /NOON CST/ THIS MORNING TO 5 PM
MST /6 PM CST/ THIS AFTERNOON FOR KSZ001>004-013>016-
027>029-041-042.
WIND ADVISORY UNTIL 5 AM MST /6 AM CST/ EARLY THIS MORNING FOR
KSZ001>004-013>016-027>029-041-042.
NE...HIGH WIND WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
NEZ079>081.
RED FLAG WARNING FROM 11 AM MST /NOON CST/ THIS MORNING TO 5 PM
MST /6 PM CST/ THIS AFTERNOON FOR NEZ079>081.
WIND ADVISORY UNTIL 5 AM MST /6 AM CST/ EARLY THIS MORNING FOR
NEZ079>081.
CO...HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ090>092.
RED FLAG WARNING FROM 11 AM THIS MORNING TO 5 PM MST THIS
AFTERNOON FOR COZ252>254.
WIND ADVISORY UNTIL 5 AM MST EARLY THIS MORNING FOR COZ090>092.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
529 AM CST SAT NOV 26 2011
.AVIATION...
FOR THE 12Z TAF ISSUANCE...VERY STRONG NORTHERLY WINDS WILL
PERSIST AT THE TAF SITES THROUGH TODAY. LOOK FOR SUSTAINED WINDS
AROUND 30 TO 40 KNOTS WITH GUSTS TO AROUND 50 KNOTS AT GARDEN CITY
AND DODGE CITY WITH WINDS NEARLY THAT STRONG AT HAYS. THERE COULD
ALSO BE A PERIOD OF LIGHT RAIN CHANGING TO LIGHT SNOW ALONG WITH
MVFR CIGS FROM AROUND 12Z TO 16Z. A PERIOD OF MVFR VSBYS IN LIGHT
SNOW WILL BE POSSIBLE AT HAYS FOR A WHILE THIS MORNING. VFR
CONDITIONS WILL BE PREVAILING AT ALL THE TAF SITES BY 16Z-18Z.
NORTH WINDS WILL DECREASE INTO THE 15 TO 25 KNOT RANGE AFTER 00Z.
&&
.PREV DISCUSSION... /ISSUED 309 AM CST SAT NOV 26 2011/
SYNOPSIS...
UPPER AIR ANALYSIS SHOWS THAT A LARGE TROF IS MOVING ACROSS THE
PLAINS THIS MORNING. THIS FEATURE CAUSED THE PRECIPITATION EVENT
THAT OCCURRED LAST NIGHT AND BROUGHT THE WELCOMED RAINS. A COLD
FRONT WAS PUSHING INTO WESTERN KANSAS EARLY THIS MORNING AND WILL
BE THE MAIN IMPACT TODAY IN TERMS OF WEATHER.
DISCUSSION...
DAYS 1-2...
IMMEDIATE CONCERN IS THE PRECIPITATION MOVING OUT OF THE AREA. KDDC
WSR-88D SHOWS THAT THE PRECIPITATION SHIELD IS SLOWLY MOVING OUT
OF THE CWFA AND HAVE TAPERED POPS DOWN AS A RESULT. I HAVE 15 PERCENT
POPS NORTH WHERE THE GFS AND THE RUC ARE INDICATING THE POTENTIAL FOR
A FEW SPRINKLES OR FLURRIES.
THE OTHER FOCUS TODAY IS WIND. 1 KM WINDS ARE AROUND 50 KT WITH 850
HPA WINDS IN THE 45 TO 55 KT RANGE. A FRONT IS MOVING ACROSS WESTERN
KANSAS EARLY THIS MORNING WITH STRONG WINDS ALREADY BEING REPORTED ACROSS
THE HIGH PLAINS OF EASTERN COLORADO. THE MOST RECENT HRRR SHOWS 10M
WINDS AROUND 35 KT THROUGH THIS AFTERNOON. AS A RESULT, HAVE ISSUED
A HIGH WIND WARNING FOR POINTS WEST OF A LINE FROM TREGO TO CLARK
COUNTIES. FURTHER EAST TOWARDS HAYS, THE MOS GUIDANCE IS MORE
MARGINAL SO HAVE DECIDED TO KEEP THE AREA EAST OF A LINE FROM ELLIS
TO COMANCHE COUNTIES IN A WIND ADVISORY. FURTHER WEST, MOS GUIDANCE
WAS SUPPORTING WIND WARNING CRITERIA WITH FORECAST OF 40G50KT AT
GARDEN CITY AND LIBERAL. SINCE WE WILL HAVE A NORTHWESTERLY
DOWNSLOPE COMPONENT, I INCREASED TEMPERATURES A DEGREE OR TWO ABOVE
GUIDANCE. TEMPERATURES SHOULD WARM TO THE UPPER 40S TO LOWER 50S.
THE FIRE WEATHER WATCH WAS ALSO CANCELLED AS RH`S NOW LOOK LIKE TO NOT
MEET THE 15 PERCENT CRITERIA. FOR MORE INFORMATION, SEE THE FIRE WEATHER
AFD SECTION BELOW.
BY TONIGHT, WE WILL HAVE NORTHERLY FLOW ALOFT IN THE WAKE OF THE UPPER
LEVEL TROF. SKIES SHOULD CLEAR AS DRY AIR ADVECTION STARTS THROUGH THE
ATMOSPHERIC COLUMN SO AM EXPECTING COOLER OVERNIGHT LOWS...GENERALLY IN
THE 20S.
THE WEATHER WILL STILL BE QUIET SUNDAY AS 500 HPA HEIGHTS INCREASE IN
RESPONSE TO RIDGING ACROSS THE DESERT SOUTHWEST. POPS WILL REMAIN
AT ZERO. MAX TEMPERATURES ARE EXPECTED IN THE 50S WHICH IS SLIGHTLY
ABOVE NORMAL.
DAYS 3-7...
THE 00Z RUNS OF THE MEDIUM RANGE MODELS HAVE COME INTO BETTER
AGREEMENT IN HANDLING THE UPPER TROUGH THAT IS CURRENTLY MOVING OUT
INTO THE CENTRAL CONUS. THE GFS HAS TRENDED TOWARD THE OTHER MODELS
IN THAT IT IS NOW CLOSING OFF AN UPPER LOW OVER THE LOWER
MISSISSIPPI VALLEY SIMILAR TO...BUT NOT AS FAR SOUTH...AS THE ECMWF.
ANY SENSIBLE WEATHER IMPACTS FROM THIS WILL BE WELL TO THE EAST OF
WESTERN KANSAS. THE MODELS CONTINUE TO SHOW THE NEXT STRONG
SHORTWAVE TROUGH MOVING EAST THROUGH THE NORTHERN CONUS WITH SOME
SHORTWAVE ENERGY MOVING SOUTHEAST OVER THE CENTRAL HIGH PLAINS.
ANOTHER STRONG COLD FRONT WILL PUSH SOUTH THROUGH WESTERN KANSAS LATE
MONDAY AFTERNOON AND EVENING. THE MODELS ARE NOT INDICATING MUCH IN
THE WAY OF PRECIPITATION WITH THIS FRONT. THIS LOOKS REASONABLE
GIVEN THAT LOW LEVEL MOISTURE WILL NOT HAVE AN OPPORTUNITY TO RETURN
NORTHWARD IN THE WAKE OF TODAYS UPPER TROUGH. THERE COULD BE A
PERIOD OF STRONG WINDS BEHIND THE FRONT AS AT LEAST THE GFS IS
SHOWING 850 MB WINDS TO 50 KNOTS.
THE MIDDLE PART OF NEXT WEEK SHOULD BE FAIRLY QUIET AS UPPER LEVEL
RIDGING MOVES OVER THE CENTRAL PLAINS. HOWEVER...ANOTHER UPPER
TROUGH WILL BE DIGGING SOUTH INTO THE WESTERN STATES. THE MODELS ARE
DIFFERING IN SOMEWHAT IN HOW THIS SYSTEM DEVELOPS BUT THEY ALL
DEVELOP IT INTO A CLOSED LOW OVER SOUTHERN CALIFORNIA/ARIZONA BY
NEXT FRIDAY. THE MODELS BRING ANOTHER COLD FRONT WITH MUCH COOLER
AIR SOUTH ACROSS WESTERN KANSAS AROUND THURSDAY OR FRIDAY AND THEN
MOVE THE UPPER LOW EAST TOWARD THE CENTRAL AND SOUTHERN PLAINS NEXT
WEEKEND. THIS COULD HAVE SOME SIGNIFICANT WEATHER IMPACTS WITH THE
POSSIBILITY FOR A SNOWSTORM ACROSS SOUTHWEST KANSAS NEXT WEEKEND
DEPENDING ON THE TRACK OF THE UPPER LOW.
FIRE WEATHER...
HAVE CANCELLED THE FIRE WEATHER WATCH AS UPSTREAM DEWPOINT OBSERVATIONS
ARE SHOWING THAT THE MODEL DEWPOINTS ARE RUNNING A LITTLE LOW. EVEN
WARMING UP TEMPERATURES AND ARTIFICIALLY LOWERING DEWPOINTS ONLY PRODUCES
RH`S IN THE 20 TO 30 PERCENT RANGE. WINDS WILL BE STRONG TODAY THOUGH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 47 25 54 31 / 40 0 0 0
GCK 46 23 55 31 / 20 0 0 0
EHA 45 23 58 35 / 10 0 0 0
LBL 47 23 56 32 / 20 0 0 0
HYS 48 24 52 30 / 20 0 0 0
P28 50 27 53 30 / 40 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 6 PM CST /5 PM MST/ THIS EVENING FOR
KSZ030-043>045-061>064-074>078-084>088.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR KSZ031-046-065-066-
079>081-089-090.
&&
$$
FN36/02/02
AREA FORECAST DISCUSSION
NWS GOODLAND KS
240 AM MST SAT NOV 26 2011
.SHORT TERM (TODAY-MONDAY)...
240 AM MST SAT NOV 26 2011
EARLY MORNING WV IMAGERY AND RUC H5 ANALYSIS SHOW AMPLIFIED
RIDGE-TROUGH-RIDGE PATTERN OVER THE CONUS...WITH MEAN TROUGH AXIS
CENTERED ALONG CO/KS STATE LINE. AT THE SURFACE COLD FRONT CURRENTLY
SOUTHEAST OF CWA...WITH SURFACE HIGH PRESSURE QUICKLY BUILDING IN
BEHIND FRONT OVER CWA. UPSTREAM 3HR PRESSURE RISES AROUND 7MB HAVE
BEEN OBSERVED OVER PARTS OF EASTERN WYOMING/WESTERN NEBRASKA...WITH
3-5MB PRESSURE RISES OVER WESTERN PARTS OF CWA. VAD WIND PROFILER
DATA SHOWS 45-55KT LOW LEVEL JET OVERHEAD...WITH LOCAL OBSERVATIONS
REPORTING SURFACE WINDS GUSTING 45-48KT.
IMMEDIATE FORECAST CONCERNS IN THE SHORT RANGE ARE ON PRECIP CHANCES
EARLY THIS MORNING AND HIGH WINDS THROUGH THIS AFTERNOON.
RIGHT ENTRANCE REGION OF H25-H3 JET COMBINED WITH STEEP MID LEVEL
LAPSE RATES HAVE LED TO DEVELOPMENT ON SCT-ISO SHOWERS OVER NE
COLORADO...WHICH HAS PROGRESSED EAST INTO SW NEBRASKA AND EXTREME NW
KANSAS EARLY THIS MORNING. AS CAA CONTINUES EXPECT MOST LOCATION TO
SEE SNOW BECOME PREDOMINANT PRECIP TYPE. WEAK MOISTURE ADVECTION
COMBINED WITH BUILDING SUBSIDENCE ALOFT SHOULD LIMIT PRECIP
AMOUNTS...SO ONLY EXPECTING LOCALIZED SNOW TOTALS OF LESS THAN ONE
HALF INCH...WHILE MOST LOCATIONS WILL STRUGGLE TO SEE EVEN A FEW
TENTHS OF AN INCH DUE TO MELTING. GUIDANCE SNOWS STRONG SUBSIDENCE
OVERTAKING AREA BY 12Z ALONG WITH VERY DRY AIR ADVECTING IN OVER THE
AREA...WHICH SHOULD END PRECIP CHANCES. WILL KEEP FORECAST DRY AFTER
12Z FOR NOW AND ADJUST BASED ON TRENDS.
WIND FORECAST IS CURRENTLY ON TRACK...WITH WIND GUSTS EARLY THIS
MORNING ALREADY ON HIGH END OF WIND ADVISORY OVER MOST THE AREA. RUC
CURRENTLY HAS BEST HANDLE ON H85-H7 WINDS BASED ON PROFILER
DATA...AND SHOWS 50KT H85 JET SPREADING EAST OVER REMAINING CWA.
WHILE PEAK PRESSURE RISES OCCUR BEFORE 12Z THIS MORNING...PERSISTENT
50KT H85 JET AND INCREASED MIXING AFTER SUNRISE SHOULD SUPPORT WINDS
INCREASING TO WARNING CRITERIA. THE STRONGEST SURFACE WINDS SHOULD
THEN DECREASE TOWARDS 00Z AS MIXING DECREASES AND WINDS ALOFT BEGIN
TO SLACKEN.
TONIGHT-MONDAY NIGHT...H5 RIDGE BUILDS EAST AND STRENGTHENS OVER SW
CONUS...WITH SHORTWAVE RIDGE AXIS EXTENDING NORTH ACROSS CWA BY MON
NIGHT. LARGE SCALE SUBSIDENCE AND DEEP DRY AIR MASS OVER CWA WILL
HELP KEEP CONDITIONS DRY THROUGH THESE PERIODS WITH TEMPS WARMING TO
ABOUT 10-15F ABOVE NORMAL SUN/MON. TEMPS A LITTLE TRICKY ON MON AS
SHORTWAVE AND ASSOCIATED COLD FRONT MOVES ACROSS REGION. GUIDANCE
CONTINUING TO DIFFER ON POSITION/TIMING OF FRONT...WHICH WILL IMPACT
HIGH TEMPS MON ALONG WITH GUSTY WINDS MON AFTERNOON. FOR NOW HAVE
KEPT IN LINE WITH PREVIOUS FORECAST OF UPPER 50S NORTH/LOW 60S
SOUTH...HOWEVER TEMPS MAY END UP NEEDING TO BE LOWERED IF FASTER
FRONTAL TIMING OF SREF/GEM WERE TO BE REALIZED.
DR
.LONG TERM (TUESDAY-FRIDAY)...
240 AM MST SAT NOV 26 2011
AN UPPER LEVEL RIDGE WILL BUILD INTO THE TRI-STATE AREA THROUGH
THURSDAY. MODELS THEN BEGIN TO DISAGREE AS TO HOW QUICKLY THE
UPPER LEVEL RIDGE MOVES EAST AS THE UPPER LEVEL TROUGH BUILDS IN AND
WHEN THE COLD FRONT WILL MOVE THROUGH THURSDAY. AS A RESULT
HIGH TEMPERATURES FOR THURSDAY VARY SIGNIFICANTLY BETWEEN THE
MODELS. FRONTAL TIMING WILL ALSO AFFECT THE ARRIVAL AND TYPE OF
PRECIPITATION. CURRENT CONSENSUS HAS THE PRECIP. OCCURRING DURING
THE DAY FOR MOST OF THE CWA. DIFFICULT TO NAIL DOWN PRECIP. TYPE
THURSDAY DUE TO THE DIFFERENCE IN FRONTAL TIMING. GENERALLY HAVE
SNOW IN THE NORTHWEST AND FAR NORTH CWA WHICH TRANSITIONS TO A
NARROW BAND OF RAIN-SNOW MIX FOLLOWED BY RAIN FURTHER SOUTH. BEHIND
THE FRONT THE 850MB WINDS WILL BE GUSTY. HOWEVER MODELS DISAGREE
WITH THE TIMING AND PLACEMENT OF THE WINDS BEHIND THE FRONT...BUT
CONSENSUS HAS BREEZY CONDITIONS THURSDAY AFTERNOON. AFTER THURSDAY
THE UPPER LEVEL FLOW TURNS TO THE SOUTHWEST AND THE ENVIRONMENT
DRIES OUT. HOWEVER TEMPERATURES WILL REMAIN COOL AFTER THURSDAY AS
THE UPPER LEVEL TROUGH MOVES TOWARD THE AREA.
JTL
&&
.AVIATION...
949 PM MST FRI NOV 25 2011
FOR THE 06Z TAFS...STRONG WINDS THROUGH MUCH OF THE PERIOD AND THE
POSSIBILITY FOR MVFR CEILINGS EARLY IN THE PERIOD WILL BE THE MAIN
CONCERNS. WHILE WINDS WILL BE STRONG TONIGHT BEHIND THE
FRONT...WINDS WILL BE STRONGER STILL DURING THE DAYTIME ON
SATURDAY AS WINDS MIX DOWNWARD. HAVE INCLUDED 45 KNOT DAYTIME WINDS
IN THE TAFS...BUT THERE IS THE POTENTIAL FOR GUSTS TO BE EVEN
HIGHER CONSIDERING THE 850 MB WINDS FROM THE MOST RECENT MODEL
RUNS. THERE IS A CHANCE FOR MVFR CEILINGS IN THE 08Z TO 10Z TIME
FRAME. MODEL SOUNDINGS ARE INDICATING BETTER CHANCES FOR MVFR
CEILINGS AT KGLD AND WORSE AT KMCK COMPARED TO EARLIER TODAY...SO
HAVE ONLY INCLUDED MVFR CONDITIONS AT KGLD.
CJS
&&
.FIRE WEATHER...
240 AM MST SAT NOV 26 2011
RED FLAG WARNING CURRENTLY IN EFFECT FOR THIS AFTERNOON ACROSS
CWA. TD VALUES HAVE BEEN SLOWER TO DECREASE THAN PREVIOUS GUIDANCE
INDICATED...HOWEVER FINALLY BEGINNING TO SEE 10-15F TD VALUES
ADVECTING INTO EASTERN COLORADO. SINGLE DIGIT TD VALUES OVER
WYOMING SHOULD EVENTUALLY ADVECT OVER CWA...AND DESPITE AFTERNOON
TEMPS IN THE UPPER 30S/LOW 40S...CURRENTLY THINK RH VALUES 18-25%
SEEM REASONABLE. COMBINED WITH VERY STRONG WINDS THIS
AFTERNOON...CRITICAL FIRE CONDITIONS WILL CONTINUE TO BE A
CONCERN...SO NO CHANGES PLANNED FOR CURRENT HIGHLIGHT.
CRITICAL FIRE CONDITIONS WILL BE POSSIBLE AGAIN MONDAY AFTERNOON.
TIMING OF STRONGEST WINDS AND LOCATION OF LOWEST TD VALUES WILL
LIKELY BE DEPENDENT ON TIMING OF COLD FRONT...WHICH GUIDANCE IS
CURRENTLY DOING A POOR JOB OF TIMING OUT...SO WILL NEED TO MONITOR
THIS.
DR
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ001>004-013>016-027>029-041-042.
RED FLAG WARNING FROM 11 AM MST /NOON CST/ THIS MORNING TO 5 PM
MST /6 PM CST/ THIS AFTERNOON FOR KSZ001>004-013>016-
027>029-041-042.
WIND ADVISORY UNTIL 5 AM MST /6 AM CST/ EARLY THIS MORNING FOR
KSZ001>004-013>016-027>029-041-042.
NE...HIGH WIND WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
NEZ079>081.
RED FLAG WARNING FROM 11 AM MST /NOON CST/ THIS MORNING TO 5 PM
MST /6 PM CST/ THIS AFTERNOON FOR NEZ079>081.
WIND ADVISORY UNTIL 5 AM MST /6 AM CST/ EARLY THIS MORNING FOR
NEZ079>081.
CO...HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ090>092.
RED FLAG WARNING FROM 11 AM THIS MORNING TO 5 PM MST THIS
AFTERNOON FOR COZ252>254.
WIND ADVISORY UNTIL 5 AM MST EARLY THIS MORNING FOR COZ090>092.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
309 AM CST SAT NOV 26 2011
.SYNOPSIS...
UPPER AIR ANALYSIS SHOWS THAT A LARGE TROF IS MOVING ACROSS THE
PLAINS THIS MORNING. THIS FEATURE CAUSED THE PRECIPITATION EVENT
THAT OCCURRED LAST NIGHT AND BROUGHT THE WELCOMED RAINS. A COLD
FRONT WAS PUSHING INTO WESTERN KANSAS EARLY THIS MORNING AND WILL
BE THE MAIN IMPACT TODAY IN TERMS OF WEATHER.
&&
.DISCUSSION...
DAYS 1-2...
IMMEDIATE CONCERN IS THE PRECIPITATION MOVING OUT OF THE AREA. KDDC
WSR-88D SHOWS THAT THE PRECIPITATION SHIELD IS SLOWLY MOVING OUT
OF THE CWFA AND HAVE TAPERED POPS DOWN AS A RESULT. I HAVE 15 PERCENT
POPS NORTH WHERE THE GFS AND THE RUC ARE INDICATING THE POTENTIAL FOR
A FEW SPRINKLES OR FLURRIES.
THE OTHER FOCUS TODAY IS WIND. 1 KM WINDS ARE AROUND 50 KT WITH 850
HPA WINDS IN THE 45 TO 55 KT RANGE. A FRONT IS MOVING ACROSS WESTERN
KANSAS EARLY THIS MORNING WITH STRONG WINDS ALREADY BEING REPORTED ACROSS
THE HIGH PLAINS OF EASTERN COLORADO. THE MOST RECENT HRRR SHOWS 10M
WINDS AROUND 35 KT THROUGH THIS AFTERNOON. AS A RESULT, HAVE ISSUED
A HIGH WIND WARNING FOR POINTS WEST OF A LINE FROM TREGO TO CLARK
COUNTIES. FURTHER EAST TOWARDS HAYS, THE MOS GUIDANCE IS MORE
MARGINAL SO HAVE DECIDED TO KEEP THE AREA EAST OF A LINE FROM ELLIS
TO COMANCHE COUNTIES IN A WIND ADVISORY. FURTHER WEST, MOS GUIDANCE
WAS SUPPORTING WIND WARNING CRITERIA WITH FORECAST OF 40G50KT AT
GARDEN CITY AND LIBERAL. SINCE WE WILL HAVE A NORTHWESTERLY
DOWNSLOPE COMPONENT, I INCREASED TEMPERATURES A DEGREE OR TWO ABOVE
GUIDANCE. TEMPERATURES SHOULD WARM TO THE UPPER 40S TO LOWER 50S.
THE FIRE WEATHER WATCH WAS ALSO CANCELLED AS RH`S NOW LOOK LIKE TO NOT
MEET THE 15 PERCENT CRITERIA. FOR MORE INFORMATION, SEE THE FIRE WEATHER
AFD SECTION BELOW.
BY TONIGHT, WE WILL HAVE NORTHERLY FLOW ALOFT IN THE WAKE OF THE UPPER
LEVEL TROF. SKIES SHOULD CLEAR AS DRY AIR ADVECTION STARTS THROUGH THE
ATMOSPHERIC COLUMN SO AM EXPECTING COOLER OVERNIGHT LOWS...GENERALLY IN
THE 20S.
THE WEATHER WILL STILL BE QUIET SUNDAY AS 500 HPA HEIGHTS INCREASE IN
RESPONSE TO RIDGING ACROSS THE DESERT SOUTHWEST. POPS WILL REMAIN
AT ZERO. MAX TEMPERATURES ARE EXPECTED IN THE 50S WHICH IS SLIGHTLY
ABOVE NORMAL.
DAYS 3-7...
THE 00Z RUNS OF THE MEDIUM RANGE MODELS HAVE COME INTO BETTER
AGREEMENT IN HANDLING THE UPPER TROUGH THAT IS CURRENTLY MOVING OUT
INTO THE CENTRAL CONUS. THE GFS HAS TRENDED TOWARD THE OTHER MODELS
IN THAT IT IS NOW CLOSING OFF AN UPPER LOW OVER THE LOWER
MISSISSIPPI VALLEY SIMILAR TO...BUT NOT AS FAR SOUTH...AS THE ECMWF.
ANY SENSIBLE WEATHER IMPACTS FROM THIS WILL BE WELL TO THE EAST OF
WESTERN KANSAS. THE MODELS CONTINUE TO SHOW THE NEXT STRONG
SHORTWAVE TROUGH MOVING EAST THROUGH THE NORTHERN CONUS WITH SOME
SHORTWAVE ENERGY MOVING SOUTHEAST OVER THE CENTRAL HIGH PLAINS.
ANOTHER STRONG COLD FRONT WILL PUSH SOUTH THROUGH WESTERN KANSAS LATE
MONDAY AFTERNOON AND EVENING. THE MODELS ARE NOT INDICATING MUCH IN
THE WAY OF PRECIPITATION WITH THIS FRONT. THIS LOOKS REASONABLE
GIVEN THAT LOW LEVEL MOISTURE WILL NOT HAVE AN OPPORTUNITY TO RETURN
NORTHWARD IN THE WAKE OF TODAYS UPPER TROUGH. THERE COULD BE A
PERIOD OF STRONG WINDS BEHIND THE FRONT AS AT LEAST THE GFS IS
SHOWING 850 MB WINDS TO 50 KNOTS.
THE MIDDLE PART OF NEXT WEEK SHOULD BE FAIRLY QUIET AS UPPER LEVEL
RIDGING MOVES OVER THE CENTRAL PLAINS. HOWEVER...ANOTHER UPPER
TROUGH WILL BE DIGGING SOUTH INTO THE WESTERN STATES. THE MODELS ARE
DIFFERING IN SOMEWHAT IN HOW THIS SYSTEM DEVELOPS BUT THEY ALL
DEVELOP IT INTO A CLOSED LOW OVER SOUTHERN CALIFORNIA/ARIZONA BY
NEXT FRIDAY. THE MODELS BRING ANOTHER COLD FRONT WITH MUCH COOLER
AIR SOUTH ACROSS WESTERN KANSAS AROUND THURSDAY OR FRIDAY AND THEN
MOVE THE UPPER LOW EAST TOWARD THE CENTRAL AND SOUTHERN PLAINS NEXT
WEEKEND. THIS COULD HAVE SOME SIGNIFICANT WEATHER IMPACTS WITH THE
POSSIBILITY FOR A SNOWSTORM ACROSS SOUTHWEST KANSAS NEXT WEEKEND
DEPENDING ON THE TRACK OF THE UPPER LOW.
&&
.AVIATION...
FOR THE 06Z TAF ISSUANCE...
VERY STRONG NORTHERLY WINDS WILL PERSIST AT THE TAF SITES THROUGH
TODAY. LOOK FOR SUSTAINED WINDS AROUND 30 TO 40 KNOTS WITH GUSTS TO
AROUND 50 KNOTS AT GARDEN CITY AND DODGE CITY WITH WINDS NEARLY THAT
STRONG AT HAYS. THERE COULD ALSO BE A PERIOD OF LIGHT RAIN CHANGING
TO LIGHT SNOW ALONG WITH MVFR CIGS FROM AROUND 12Z TO 16Z WITH VFR
CONDITIONS PREVAILING THROUGH THE REST OF THE DAY. NORTH WINDS WILL
DECREASE INTO THE 15 TO 25 KNOT RANGE AFTER 00Z
&&
.FIRE WEATHER...
HAVE CANCELLED THE FIRE WEATHER WATCH AS UPSTREAM DEWPOINT OBSERVATIONS
ARE SHOWING THAT THE MODEL DEWPOINTS ARE RUNNING A LITTLE LOW. EVEN
WARMING UP TEMPERATURES AND ARTIFICIALLY LOWERING DEWPOINTS ONLY PRODUCES
RH`S IN THE 20 TO 30 PERCENT RANGE. WINDS WILL BE STRONG TODAY THOUGH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 47 25 54 31 / 40 0 0 0
GCK 46 23 55 31 / 20 0 0 0
EHA 45 23 58 35 / 10 0 0 0
LBL 47 23 56 32 / 20 0 0 0
HYS 48 24 52 30 / 20 0 0 0
P28 50 27 53 30 / 40 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 6 PM CST /5 PM MST/ THIS EVENING FOR
KSZ030-043>045-061>064-074>078-084>088.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR KSZ031-046-065-066-
079>081-089-090.
&&
$$
FN36/02/02
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1235 PM EST SAT NOV 26 2011
...Updated Aviation Discussion...
...Forecast Update...
A few changes to the forecast this morning. First of all, light
radar echoes moving NE from southeast MO/western KY/southern IL seem
to be producing light brief rain showers. The 12Z HRRR has picked
up on this activity bringing it into our southwest Indiana counties
by early afternoon. This seems reasonable given the current radar
trends and light isentropic lift increasing throughout the day ahead
of the approaching front. Therefore expanded 20% POPs in the far
western CWA from 18Z to 0Z.
As of 10am EST, winds were already gusting out of the south between
20-25 mph with a few higher gusts noted. Based on these already
gusty conditions with BKN upper level clouds, think that we`ll see
gusts between 30-35 mph this afternoon with BKN mid and upper level
clouds continuing throughout the day.
Last, on such strong southerly flow, temps are running 2-3 degrees
warmer than previously forecast. The 12Z NAM has caught on to this
temp trend. Based on this new model data and this morning`s trends,
think that high temps should reach the upper 60s with a few lower
70s possible near the BWG area.
&&
.Short Term (Today - Sunday)...
Surface low currently over south central Minnesota will lift
northeasward across the Great Lakes through the forecast period,
with a trailing cold front moving near the western CWA border by
dawn on Sunday. Meanwhile, a full CONUS amplified trough axis will
slide from the central United States to the Middle Mississipi River
Valley by Sunday afternoon. Anomalous closed low is expected to
develop over the Ark/La/Tex region sometime on Sunday with
associated surface low situated over the Tennessee Valley.
Today...
Another dry day is in store for the CWA as model trends have
continued to be slower with precipitation ahead of aforementioned
frontal boundary. The main focus for today will be on gusty
southerly winds and how warm temperatures will get under variably
cloudy skies. Pressure gradient between southeast CONUS high and low
moving across the Great Lakes will be quite strong with southerly
winds between 15 and 20 mph, gusting up around the 30 mph mark at
times. Cannot rule out a few gusts up to the 35 mph range, depending
on how much mixing will occur. Kept wind gusts tempered compared to
potential just a bit based on expected increasing clouds throughout
the day and the impact on mixing.
High temperatures are expected to jump nicely on steady southerly
flow, into the solid mid 60s in most spots. The mercury will range
in the upper 60s near the Bowling Green region. The northwest CWA
will be the coolest in the lower 60s as mostly cloudy skies by
midday hamper heating.
Tonight and Sunday...
Precipitation chances are expected to increase west of I-65 between
7 PM and 1 AM EST as moisture convergence/ascent with 40-50 knot low
level jet ramps up across the region, coincident with the right
entrance region of the upper level jet. Best moisture/lift will
continue to spread eastward by dawn with categorical POPS along and
west of the I 65 corridor and likely POPS west of I 75. Categorical
wording will continue through the entire day on Sunday with frontal
boundary slowly working through the CWA. It should be noted that an
even slower solution could hamper the forecast with categorical rain
showers holding west of I 65 until 12Z Sunday morning as suggested
by 26/00Z SPC WRF. This is the most extreme/slow solution, so
preferred a slightly faster forecast although attention should be
paid to subsequent forecasts if slower trend continues.
Have gone with a limited diurnal trend during this time with mild
lows in the 50 to 55 degree range and highs on Sunday only in the 50
to 60 degree range, dependent on frontal passage. Areas east of I-65
will likely see the 60 degree mark early before temperatures remain
steady or gradually fall off through the day. West of this line,
expect 50 to 55 degree highs, remaining steady or gradually falling
into the upper 40s through the afternoon.
Overall precipitation amounts through Sunday afternoon should range
in the 0.75 to 1.5 inch range. At this point, the Blue Grass region
appears to be the most likely area to see just under an inch.
.Long term (Sunday Night - Friday)...
Models in pretty good agreement for the start of the period, placing
the cold front over our eastern border with JKL Sunday night and a
broad north-south trough stretching from the Gulf of Mexico over
Louisiana up to St. James Bay. Given that the upper trough lags well
behind the front, have an extensive area of post-frontal
precipitation. Thermal profiles look too warm for any frozen precip
Sunday night. Only exception may be over the NW forecast area, so
have kept in slight chances for snow there after midnight.
During the day Monday, the models now are in better agreement,
closing off a low on the southern end of the above-mentioned trough.
The GEFS/SREF/12Z and new 00Z ECMWF/NAM all place this low over MS
Monday evening, whereas the GFS has it in central TN. Will leave the
GFS as an outlier and go with the rest of the guidance for this
system. The 18Z GEFS indicates heights for the 500mb low are 4-5
standard deviations below normal. Thus expect a good feed of
moisture to come up the east side of the system from the Gulf. This
feed will mean continued precip chances until after both the axis of
the upper low and its associated deformation zone passes east of the
area, which looks like it may not occur until Wednesday morning over
the Bluegrass. The next chance for snow during this period will come
Tuesday night. Thicknesses will be at there lowest at that point,
with the cold upper low pulling east of the region and merging with
a broader trough over the area. Surface temperatures should remain
too warm for accumulations, but if the snow dominates over the rain
and falls faster than expected here, some light accumulations are
possible. Will be optimistic for now and just mention the chance for
rain or snow with no accumulations.
From that point on, assuming the closed low behaves as these models
predict, difficult to do in the long range, our area looks to dry
out some. The entire week looks chilly, with generally staying in
the 40s. Lows Monday and Tuesday morning also should be in the 40s,
with extensive cloud cover. Clearing skies for the second half of
the week will allow colder nighttime lows, to around 30.
&&
.Aviation (18Z TAF Issuance)...
Breezy conditions are expected this afternoon ahead of an
approaching frontal boundary. Winds will be out of the south
between 15-18 kts gusting to 25-30 kts. Wind gusts will subside
after sunset this evening with flight conditions remaining VFR.
Tonight the frontal boundary will approach the region bringing rain
showers and MVFR CIGS/VSBYS between 6Z-9Z. More steady rains will
set in after 11Z and last through the morning and early afternoon
hours Sun. While VSBYS may remain in the MVFR cat, CIGS will be
questionable. Will be optimistic and drop CIGS to around 1 kft for
now, but they could drop into the IFR cat.
Gusty winds will again become an issue around the time that showers
start arriving at the TAF sites late tonight. A 45-50 kt LLJ at
H925 will develop during the early morning hours making it easy for
any showers to mix down gusty winds or the mixy atmosphere ahead of
the front outside of any showers may cause windy conditions.
Therefore will insert 25 kt gusts although the 12Z NAM bufkit
soundings indicate gusts into the 30 kt range. Will need to monitor
that.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........AMS
Short Term.......BJS
Long Term........RJS
Aviation.........AMS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1056 AM EST SAT NOV 26 2011
...Forecast Update...
A few changes to the forecast this morning. First of all, light
radar echoes moving NE from southeast MO/western KY/southern IL seem
to be producing light brief rain showers. The 12Z HRRR has picked
up on this activity bringing it into our southwest Indiana counties
by early afternoon. This seems reasonable given the current radar
trends and light isentropic lift increasing throughout the day ahead
of the approaching front. Therefore expanded 20% POPs in the far
western CWA from 18Z to 0Z.
As of 10am EST, winds were already gusting out of the south between
20-25 mph with a few higher gusts noted. Based on these already
gusty conditions with BKN upper level clouds, think that we`ll see
gusts between 30-35 mph this afternoon with BKN mid and upper level
clouds continuing throughout the day.
Last, on such strong southerly flow, temps are running 2-3 degrees
warmer than previously forecast. The 12Z NAM has caught on to this
temp trend. Based on this new model data and this morning`s trends,
think that high temps should reach the upper 60s with a few lower
70s possible near the BWG area.
&&
.Short Term (Today - Sunday)...
Surface low currently over south central Minnesota will lift
northeasward across the Great Lakes through the forecast period,
with a trailing cold front moving near the western CWA border by
dawn on Sunday. Meanwhile, a full CONUS amplified trough axis will
slide from the central United States to the Middle Mississipi River
Valley by Sunday afternoon. Anomalous closed low is expected to
develop over the Ark/La/Tex region sometime on Sunday with
associated surface low situated over the Tennessee Valley.
Today...
Another dry day is in store for the CWA as model trends have
continued to be slower with precipitation ahead of aforementioned
frontal boundary. The main focus for today will be on gusty
southerly winds and how warm temperatures will get under variably
cloudy skies. Pressure gradient between southeast CONUS high and low
moving across the Great Lakes will be quite strong with southerly
winds between 15 and 20 mph, gusting up around the 30 mph mark at
times. Cannot rule out a few gusts up to the 35 mph range, depending
on how much mixing will occur. Kept wind gusts tempered compared to
potential just a bit based on expected increasing clouds throughout
the day and the impact on mixing.
High temperatures are expected to jump nicely on steady southerly
flow, into the solid mid 60s in most spots. The mercury will range
in the upper 60s near the Bowling Green region. The northwest CWA
will be the coolest in the lower 60s as mostly cloudy skies by
midday hamper heating.
Tonight and Sunday...
Precipitation chances are expected to increase west of I-65 between
7 PM and 1 AM EST as moisture convergence/ascent with 40-50 knot low
level jet ramps up across the region, coincident with the right
entrance region of the upper level jet. Best moisture/lift will
continue to spread eastward by dawn with categorical POPS along and
west of the I 65 corridor and likely POPS west of I 75. Categorical
wording will continue through the entire day on Sunday with frontal
boundary slowly working through the CWA. It should be noted that an
even slower solution could hamper the forecast with categorical rain
showers holding west of I 65 until 12Z Sunday morning as suggested
by 26/00Z SPC WRF. This is the most extreme/slow solution, so
preferred a slightly faster forecast although attention should be
paid to subsequent forecasts if slower trend continues.
Have gone with a limited diurnal trend during this time with mild
lows in the 50 to 55 degree range and highs on Sunday only in the 50
to 60 degree range, dependent on frontal passage. Areas east of I-65
will likely see the 60 degree mark early before temperatures remain
steady or gradually fall off through the day. West of this line,
expect 50 to 55 degree highs, remaining steady or gradually falling
into the upper 40s through the afternoon.
Overall precipitation amounts through Sunday afternoon should range
in the 0.75 to 1.5 inch range. At this point, the Blue Grass region
appears to be the most likely area to see just under an inch.
.Long term (Sunday Night - Friday)...
Models in pretty good agreement for the start of the period, placing
the cold front over our eastern border with JKL Sunday night and a
broad north-south trough stretching from the Gulf of Mexico over
Louisiana up to St. James Bay. Given that the upper trough lags well
behind the front, have an extensive area of post-frontal
precipitation. Thermal profiles look too warm for any frozen precip
Sunday night. Only exception may be over the NW forecast area, so
have kept in slight chances for snow there after midnight.
During the day Monday, the models now are in better agreement,
closing off a low on the southern end of the above-mentioned trough.
The GEFS/SREF/12Z and new 00Z ECMWF/NAM all place this low over MS
Monday evening, whereas the GFS has it in central TN. Will leave the
GFS as an outlier and go with the rest of the guidance for this
system. The 18Z GEFS indicates heights for the 500mb low are 4-5
standard deviations below normal. Thus expect a good feed of
moisture to come up the east side of the system from the Gulf. This
feed will mean continued precip chances until after both the axis of
the upper low and its associated deformation zone passes east of the
area, which looks like it may not occur until Wednesday morning over
the Bluegrass. The next chance for snow during this period will come
Tuesday night. Thicknesses will be at there lowest at that point,
with the cold upper low pulling east of the region and merging with
a broader trough over the area. Surface temperatures should remain
too warm for accumulations, but if the snow dominates over the rain
and falls faster than expected here, some light accumulations are
possible. Will be optimistic for now and just mention the chance for
rain or snow with no accumulations.
From that point on, assuming the closed low behaves as these models
predict, difficult to do in the long range, our area looks to dry
out some. The entire week looks chilly, with generally staying in
the 40s. Lows Monday and Tuesday morning also should be in the 40s,
with extensive cloud cover. Clearing skies for the second half of
the week will allow colder nighttime lows, to around 30.
&&
.Aviation (12Z TAF Issuance)...
Expecting VFR to prevail through the majority of the forecast period
with deteriorating conditions right at the end and beyond the
forecast period. Strong pressure gradient between a surface low over
the upper Midwest and surface high off the Carolina coast will keep
steady winds out of the south through the forecast period. Although
surface winds are expected to stay up slightly through mid morning,
a low level jet between 35-40 knots will allow for LLWS below 2 K
feet up to 40 knots. LLWS has been confirmed by AMDAR soundings in
the Louisville region overnight.
Expect SCT to, at times, BKN cumulus clouds between 3 and 4 K feet
on Saturday afternoon with south winds between 15 and 20 mph gusting
to around 30 mph at times. Low level clouds will be on the increase
this evening with rain chances at BWG and SDF increasing after
midnight as frontal boundary approaches. LEX will likely hold off on
rain until around dawn on Sunday. Once the rain arrives, expect
prevailing MVFR conditions with occasional IFR conditions possible.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........AMS
Short Term.......BJS
Long Term........RJS
Aviation.........BJS
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1003 PM EST SUN NOV 27 2011
.SYNOPSIS...
HIGH PRESSURE STAYS OFF TO THE EAST THROUGH MONDAY. AN AREA OF
LOW PRESSURE WILL DEVELOP OVER THE DEEP SOUTH EARLY MONDAY AND
WILL AFFECT THE MID ATLANTIC STATES LATE MONDAY NIGHT AND TUESDAY.
HIGH PRESSURE RETURNS FOR THE MIDDLE AND LATTER HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
BANDS OF CU LIFTING NORTHWARD AS LOW-LEVEL MOISTURE CONTINUES TO
INCREASE W/ SOUTHERLY FLOW. THIS PATTERN OF SOUTHERLY FLOW WILL
CONTINUE THROUGH MONDAY NIGHT AS A SFC HIGH STAYS OFF TO THE EAST AND
AN UPPER TROUGH DIGS INTO THE LOWER MISSISSIPPI BEFORE CLOSING
OFF. WITH INCREASING LOW-LEVEL MOISTURE...EXPECT TO SEE A GRADUAL
INCREASE IN THE CLOUDS TONIGHT THROUGH THE DAY MONDAY WITH THE
MOST CLOUDS IN THE THE LEE OF THE PIEDMONT WITH THE TURNING OF THE
FLOW TO THE SE. MID-LEVELS REMAIN DRY SO DO NOT SEE ANY CHANCE OF
RAIN TONIGHT OR MONDAY. ON MONDAY NIGHT AS THE UPPER LOW BEGINS TO
LIFT NEWD AND THE SURFACE FRONT BEGINS ITS APPROACH...COULD BEGIN
TO SEE SOME SHOWERS DEVELOP IN ADVANCE OF THE FRONT...BUT NOT
ANTICIPATING MUCH ACTIVITY UNTIL AFTER 6Z TUES.
FOR TEMPS...WITH THE MOIST SOUTHERLY FLOW...SHOULD SEE THE MILD
READINGS CONTINUE...LOWS MAINLY IN THE MID 50S. HIGHS MONDAY WILL
BE WARM AGAIN...UPPER 60S TO LOWER 70S. CLOUDS COULD LIMIT THE
HEATING SOME...BUT BEING IN THE WARM SECTOR...THERE SHOULD BE SOME
SUNSHINE AROUND. WITH THE APPROACH OF THE FRONT AND THICKENING
CLOUDS...TEMPS WILL STAY IN THE MID 50S TO AROUND 60 MONDAY NIGHT AS
THE MOISTURE CONTINUES TO INCREASE.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
GOING WITH A COMBINATION OF THE 12Z GFS...NAM...AND ECMWF MDLS WITH
REGARD TO TIMING OF FRNTL BNDRY AND ASSOC SHOWERS MOVNG ACRS THE
REGION DURING TUE. ONLY VRY WEAK INSTABILITY EXPECTED DURING TUE
EVEN THO TEMPS CLIMB INTO THE MID 60S OVR ERN PORTIONS OF THE AREA.
SO...SLGT CHC OF THUNDER IS ENOUGH. BULK OF PCPN WILL END GENERALLY
FM W TO E LATER TUE AFTN INTO TUE EVENG...AS FRNTL BNDRY EVENTUALLY
SLIDES OFF THE CST. MOST AREAS CUD RECEIVE BETWEEN .25 TO .50 INCH
OF RAINFALL WITH THIS SYSTEM...WITH HIER AMTS ACRS THE NRN CNTIES.
SLGT OR SML CHC OF SHOWERS...MAINLY OVR NRN THIRD OF THE AREA...WILL
LINGER LATE TUE NGT THRU WED...AS UPR LO LIFTS FM W.VA NNE INTO SE
CANADA. OTHRWISE...SHUD SEE A PRTLY SNY SKY ON WED. HIGHS ON TUE IN
THE UPR 50S TO MID 60S. LOWS TUE NGT IN THE UPR 30S TO LWR 40S.
HIGHS ON WED IN THE LWR TO MID 50S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
FOLLOWED CLOSE TO HPC BUT USED SOME ELEMENTS OF THE GFS/EURO. ON THE
HEELS OF A POTENT STORM SYSTEM...THE LONG TERM LOOKS DRY AND COOL.
AN ACTIVE NORTHERN STREAM WILL SEND SHORT WAVES THROUGH THE AREA BUT
THEY LOOK TO BE DRY. UPPER LEVEL HIGH OVER THE GULF OF MEXICO REGION
WILL NUDGE TOWARD THE SOUTHEAST STATES TOWARD NEXT WEEKEND. AT THE
SURFACE...POLAR HIGH PRESSURE WILL SLOWLY BUILD INTO THE AREA...
INTERRUPTED BY A REINFORCING COLD FRONT LATE FRIDAY.
HIGH TEMPERATURES WILL GENERALLY BE IN THE LOW TO MID 50S BUT
COOL TO THE MID 40S TO AROUND 50 ON SATURDAY. LOW TEMPERATURES WILL
BE MAINLY IN THE 30S...WITH SOME MID TO UPPER 20S WELL INLAND BY
SUNDAY MORNING.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUE. SFC HIGH PUSHES FARTHER OFFSHORE TONIGHT
AS A FRONTAL BOUNDARY MOVES THROUGH THE OHIO VALLEY. LOW LEVEL
MOISTURE CONTINUES TO WRAP AROUND THE SFC HIGH AND IS PRODUCING A
CU FIELD AROUND 4-6K FT. THIS MOISTURE WILL CONTINUE TO SPREAD
NORTHWARD INTO MONDAY. A LITTLE CONCERNED THAT AS THE WINDS TURN
A BIT MORE SE COULD SEE SOME MVFR CEILINGS...BUT FOR NOW HAVE HELD
CEILINGS ABOVE 3K FT. FOG UNLIKELY TONIGHT DUE TO 5-10 KT WINDS
AND THE BKN/OVC DECK ALOFT.
AFTER 18Z MONDAY...WILL SEE AN AREA OF LOW PRESSURE FORM ALONG THE
COLD FRONT OVER THE GULF COAST STATES. THIS LOW MOVES NORTHWARD
INTO THE OHIO VALLEY WITH THE COLD FRONT SWINGING THROUGH THE SERN
U.S. INTO THE MID ATLANTIC STATES TUESDAY. THIS WILL RESULT IN
SHOWERS WITH POSSIBLE MVFR CONDITIONS. THE FLOW TURNS SWRLY BEHIND
THE FRONT WHICH SHOULD BEGIN THE CLEARING PROCESS WITH VFR
CONDITIONS RETURNING.
&&
.MARINE...
SOUTHERLY WINDS WERE AROUND 15 KNOTS SUNDAY AFTN. SENSORS THAT ARE
NOT ELEVATED AND ARE AWAY FROM THE WESTERN SHORE OF THE BAY ARE
HOLDING WELL BELOW SCA CRITERIA. THE 18Z NAM AND RUC ARE HANDLING
THIS WELL AND INDICATE A DECREASE IN WINDS TOWARDS MIDNIGHT.
WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA UNTIL THE EARLY
MORNING HOURS OF TUESDAY (LATE MONDAY NIGHT) WHEN A SOUTHEAST FETCH
OVER THE COASTAL WATERS IS EXPECTED TO BRING 5 FOOT SEAS TO WITHIN
20 MILES OF OUR SHORE. SE WINDS WILL RUN AROUND 20 KNOTS OVER THE
BAY AND POSSIBLY CURRITUCK SOUND ON TUESDAY RESULTING IN THE
LIKELIHOOD OF SCA HEADLINES. WINDS TURN TO SW BY TUESDAY NIGHT AND
MAY INCREASE TO 20-25 KNOTS OVER THE COASTAL WATERS...ESPECIALLY
OVER NORTHERN PORTIONS. WINDS AND SEAS SHOULD DECREASE TO BELOW SCA
CRITERIA BY LATE WEDNESDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ESS/MAS
NEAR TERM...ESS/MAS
SHORT TERM...TMG
LONG TERM...LSA
AVIATION...ESS/MAS
MARINE...LSA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
638 PM EST SUN NOV 27 2011
.SYNOPSIS...
HIGH PRESSURE SLOWLY EDGES OFF THE COAST THROUGH MONDAY. AN AREA OF
LOW PRESSURE WILL DEVELOP OVER THE DEEP SOUTH BY EARLY MONDAY AND WILL
AFFECT THE MID ATLANTIC STATES LATE MONDAY NIGHT AND TUESDAY. HIGH
PRESSURE RETURNS FOR THE MIDDLE AND LATTER HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
SATELLITE CONTINUES TO SHOW BANDS OF CU TRYING TO LIFT NORTHWARD
AS THE LOW-LEVEL MOISTURE CONTINUES TO INCREASE IN THE SOUTHERLY
FLOW. THIS PATTERN OF SOUTHERLY FLOW WILL CONTINUE THROUGH MONDAY
NIGHT AS A SURFACE HIGH CONTINUES TO SLIDE OFF INTO THE WESTERN
ATLANTIC AND AN UPPER TROUGH DIGS INTO THE LOWER MISSISSIPPI BEFORE
CLOSING OFF. WITH THE INCREASING OF THE LOW-LEVEL
MOISTURE...EXPECT TO SEE A GRADUAL INCREASE IN THE CLOUDS TONIGHT
THROUGH THE DAY ON MONDAY WITH THE MOST CLOUDS IN THE THE LEE OF
THE PIEDMONT WITH THE TURNING OF THE FLOW TO THE SE. THE MID-LEVELS
REMAIN DRY SO DO NOT SEE ANY CHANCE OF RAIN TONIGHT OR MONDAY. ON
MONDAY NIGHT AS THE UPPER LOW BEGINS TO LIFT NEWD AND THE SURFACE
FRONT BEGINS ITS APPROACH...COULD BEGIN TO SEE SOME SHOWERS
DEVELOP IN ADVANCE OF THE FRONT...BUT NOT ANTICIPATING MUCH
ACTIVITY UNTIL AFTER 6Z TUES.
FOR TEMPERATURES...WITH THE MOIST SOUTHERLY FLOW
CONTINUING...SHOULD SEE THE MILD READINGS CONTINUE. DID ALLOW FOR
SOME RADIATIONAL COOLING TONIGHT...BUT AGAIN IT WILL NOT BE AS
COOL AS PREVIOUS NIGHTS SO LOWS IN THE LOW TO MID 50S SHOULD BE
THE NORM. HIGHS MONDAY WILL BE WARM AGAIN IN THE UPPER 60S TO
LOWER 70S. CLOUDS COULD LIMIT THE HEATING SOME...BUT BEING IN THE
WARM SECTOR...THERE SHOULD BE SOME SUNSHINE AROUND. WITH THE
APPROACH OF THE FRONT AND THICKENING CLOUDS TEMPS WILL STAY IN THE
MID 50S TO AROUND 60 MONDAY NIGHT AS THE MOISTURE CONTINUES TO
INCREASE.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
GOING WITH A COMBINATION OF THE 12Z GFS...NAM...AND ECMWF MDLS WITH
REGARD TO TIMING OF FRNTL BNDRY AND ASSOC SHOWERS MOVNG ACRS THE
REGION DURING TUE. ONLY VRY WEAK INSTABILITY EXPECTED DURING TUE
EVEN THO TEMPS CLIMB INTO THE MID 60S OVR ERN PORTIONS OF THE AREA.
SO...SLGT CHC OF THUNDER IS ENOUGH. BULK OF PCPN WILL END GENERALLY
FM W TO E LATER TUE AFTN INTO TUE EVENG...AS FRNTL BNDRY EVENTUALLY
SLIDES OFF THE CST. MOST AREAS CUD RECEIVE BETWEEN .25 TO .50 INCH
OF RAINFALL WITH THIS SYSTEM...WITH HIER AMTS ACRS THE NRN CNTIES.
SLGT OR SML CHC OF SHOWERS...MAINLY OVR NRN THIRD OF THE AREA...WILL
LINGER LATE TUE NGT THRU WED...AS UPR LO LIFTS FM W.VA NNE INTO SE
CANADA. OTHRWISE...SHUD SEE A PRTLY SNY SKY ON WED. HIGHS ON TUE IN
THE UPR 50S TO MID 60S. LOWS TUE NGT IN THE UPR 30S TO LWR 40S.
HIGHS ON WED IN THE LWR TO MID 50S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
FOLLOWED CLOSE TO HPC BUT USED SOME ELEMENTS OF THE GFS/EURO. ON THE
HEELS OF A POTENT STORM SYSTEM...THE LONG TERM LOOKS DRY AND COOL.
AN ACTIVE NORTHERN STREAM WILL SEND SHORT WAVES THROUGH THE AREA BUT
THEY LOOK TO BE DRY. UPPER LEVEL HIGH OVER THE GULF OF MEXICO REGION
WILL NUDGE TOWARD THE SOUTHEAST STATES TOWARD NEXT WEEKEND. AT THE
SURFACE...POLAR HIGH PRESSURE WILL SLOWLY BUILD INTO THE AREA...
INTERRUPTED BY A REINFORCING COLD FRONT LATE FRIDAY.
HIGH TEMPERATURES WILL GENERALLY BE IN THE LOW TO MID 50S BUT
COOL TO THE MID 40S TO AROUND 50 ON SATURDAY. LOW TEMPERATURES WILL
BE MAINLY IN THE 30S...WITH SOME MID TO UPPER 20S WELL INLAND BY
SUNDAY MORNING.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS CONTINUE. SFC HIGH PUSHES FARTHER OFFSHORE TONIGHT
AS A FRONTAL BOUNDARY MOVES THROUGH THE OHIO VALLEY. LOW LEVEL
MOISTURE CONTINUES TO WRAP AROUND THE SFC HIGH AND IS PRODUCING A
CU FIELD AROUND 4-6K FT. THIS MOISTURE WILL CONTINUE TO SPREAD
NORTHWARD INTO MONDAY. A LITTLE CONCERNED THAT AS THE WINDS TURN
A BIT MORE SE COULD SEE SOME MVFR CEILINGS...BUT FOR NOW HAVE HELD
CEILINGS ABOVE 3K FT. FOG UNLIKELY TONIGHT DUE TO 5-10 KT WINDS
AND THE BKN/OVC DECK ALOFT.
AFTER 18Z MONDAY...WILL SEE AN AREA OF LOW PRESSURE FORM ALONG THE
COLD FRONT OVER THE GULF COAST STATES. THIS LOW MOVES NORTHWARD
INTO THE OHIO VALLEY WITH THE COLD FRONT SWINGING THROUGH THE SERN
U.S. INTO THE MID ATLANTIC STATES TUESDAY. THIS WILL RESULT IN
SHOWERS WITH POSSIBLE MVFR CONDITIONS. THE FLOW TURNS SWRLY BEHIND
THE FRONT WHICH SHOULD BEGIN THE CLEARING PROCESS WITH VFR
CONDITIONS RETURNING.
&&
.MARINE...
SOUTHERLY WINDS WERE AROUND 15 KNOTS SUNDAY AFTN. SENSORS THAT ARE
NOT ELEVATED AND ARE AWAY FROM THE WESTERN SHORE OF THE BAY ARE
HOLDING WELL BELOW SCA CRITERIA. THE 18Z NAM AND RUC ARE HANDLING
THIS WELL AND INDICATE A DECREASE IN WINDS TOWARDS MIDNIGHT.
WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA UNTIL THE EARLY
MORNING HOURS OF TUESDAY (LATE MONDAY NIGHT) WHEN A SOUTHEAST FETCH
OVER THE COASTAL WATERS IS EXPECTED TO BRING 5 FOOT SEAS TO WITHIN
20 MILES OF OUR SHORE. SE WINDS WILL RUN AROUND 20 KNOTS OVER THE
BAY AND POSSIBLY CURRITUCK SOUND ON TUESDAY RESULTING IN THE
LIKELIHOOD OF SCA HEADLINES. WINDS TURN TO SW BY TUESDAY NIGHT AND
MAY INCREASE TO 20-25 KNOTS OVER THE COASTAL WATERS...ESPECIALLY
OVER NORTHERN PORTIONS. WINDS AND SEAS SHOULD DECREASE TO BELOW SCA
CRITERIA BY LATE WEDNESDAY.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ESS
NEAR TERM...ESS/MAS
SHORT TERM...TMG
LONG TERM...LSA
AVIATION...ESS/MAS
MARINE...LSA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1240 PM EST SAT NOV 26 2011
UPDATED AVIATION DISCUSSION FOR 18Z TAFS
.UPDATE...
A LITTLE DRYING HAS MOVED INTO THE WESTERN HALF OF UPPER
MICHIGAN...WHICH HELPED TO DECREASE PCPN SOMEWHAT THIS MORNING.
HOWEVER...THE PCPN HAS REDEVELOPED AS ANOTHER WAVE MOVES THROUGH THE
AREA. WITH THIS IN MIND...HAVE OPTED TO KEEP CATEGORICAL POPS ACROSS
THE ENTIRE AREA EXCEPT THE FAR WEST WHERE ADDITIONAL PCPN WILL HAVE
TO WAIT UNTIL WRAP AROUND MOISTURE MOVES IN LATER ON TODAY. AS FOR
PCPN TYPE ACROSS THE FAR WEST...LATEST MODEL SOUNDINGS FROM IWD DO
NOT SHOW THE FREEZING LEVEL LOWERING TO BELOW 1000 FT UNTIL AFTER
00Z. THAT COMBINED WITH THE FACT THAT THE BL TEMPS WILL BE AT LEAST
IN THE MID-UPPER 30S...HAVE OPTED TO REMOVE ANY MENTION OF SNOW
UNTIL THIS EVENING.
&&
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR TROFFING OVER
THE PLAINS BTWN PERSISTENT RDG OVER THE ERN CONUS AND ANOTHER RDG
OVER THE W COAST. THERE ARE 3 SHRTWVS OF SIGNIFICANCE EMBEDDED
WITHIN THE TROF OVER THE PLAINS...ONE OVER SASKTATCHEWAN...ANOTHER
IN WYOMING...AND ANOTHER CENTERED NEAR THE TX PANHANDLE. THE COMPLEX
INTERACTION BTWN THESE SEPARATE DISTURBANCES HAS MADE THE EVOLUTION
OF THE UPCOMING WX PATTERN A BIT TRICKY FOR RECENT SHIFTS. THE
DISTURBANCE OVER WYOMING IS SUPPORTING A SFC LO OVER WCNTRL MN. A
FAIRLY WELL DEFINED COMMA CLD IS PRESENT WITH COMMA HEAD PCPN NOTED
UNDER COLDER CLD TOPS OVER THE DAKOTAS ON THE COLD SIDE OF THE
ACCOMPANYING H85 LO. THE WARM CONVEYOR BELT CLD EXTENDS THRU THE UPR
MIDWEST/UPR MS RIVER VALLEY INTO THE GRT LKS...BUT DRY AIR NOTED AT
H7 BY THE BULK OF THE RAOBS...VERY WELL SHOWN BY THE 00Z GRB/MPX
RAOBS...E OF THE UPR TROF AXIS HAS PREVENTED WDSPRD RA FM DVLPG
DESPITE INCRSG UPR DVGC UNDER COUPLED UPR JET STRUCTURE BTWN H3
SPEED MAX IN ONTARIO AND ANOTHER IN SDAKOTA/NEBRASKA. HOWEVER...THE
INTERACTION BTWN THIS DYNAMIC AND THE STRONG SW FLOW E OF THE MN LO
THAT IS ADVECTING UNSEASONABLY HI H85 DWPTS UP TO 6C FROM OMAHA TO
THRU IOWA TOWARD THE UPR MIDWEST HAS CAUSED A RECENT EXPANSION OF
THE RADAR ECHOES TO THE SW. ALTHOUGH A SFC COLD FNT...ASSOCIATED
WITH THE JET MAX IN ONTARIO...HAS SLID OVER UPR MI...TEMPS OVER UPR
MI ARE WELL ABV NORMAL IN THE UPR 30S/40S. THIS FNT HAS PRETTY MUCH
STALLED BUT COULD SERVE AS A FOCAL POINT FOR INCRSG LLVL MSTR CNVGC/
FGEN/ISENTROPIC ASCENT.
&&
.DISCUSSION...
MAIN FCST CONCERNS THRU THIS WEEKEND ARE PCPN CHCS/TYPES/POTENTIAL
SN ACCUMS AND TIMING OF DRYING TREND FOLLOWING THE PASSAGE OF UPR
TROF/SFC LO.
TDAY...RECENT MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON EXPECTED
STRENGTH/TRACK OF SFC LO THAT WL IMPACT THE CWA AHEAD OF DISTURBANCE
NOW IN WYOMING. THIS LO IS PROGGED TO MOVE TO BTWN MQT AND MUNISING
BY 00Z SUN. AS THE SFC LO NOW IN MN MOVES TOWARD UPR MI...GUIDANCE
SHOWS INCRSG ISENTROPIC ASCENT FOCUSED ON THE 290K SFC/UPR DVGC
UNDER FVRBL ORIENTATION OF UPR JET CORES/PWAT SURGING TO ALMOST 250
PCT OF NORMAL WITH THE ARRIVAL OF H85 DWPTS OF 5C. BOTH THE 00Z
NAM/GFS SHOW THE SHARPEST H85-7 FGEN ACCOMPANYING THE FVRBL
INTERACTION BTWN THESE DYNAMICS/MOISTENING AND THE FNTL BNDRY
IMPACTING MAINLY THE NW CWA WITH THE HIEST QPF THEN SHIFTING OUT
OVER LK SUP AND TO THE E IN THE AFTN. ALTHOUGH THE FCST LLVL CYC NNW
FLOW IN THE WAKE OF THE SFC LO PASSING TO THE E WL PROBABLY KEEP
SOME PCPN GOING OVER THE W...FCST DEEP LYR QVECTOR DVGC ARRIVING FM
THE SW IN THE AFTN WL LIKELY LIMIT THE INTENSITY OF THE PCPN THERE
MORE THAN EARLIER ANTICIPATED AND WEAKEN THE COMMA HEAD PCPN NOTED
OVER THE DAKOTAS EARLY THIS MRNG. THE ARRIVAL OF SOMEWHAT COLDER
LLVL AIR INTO THE W LATE...WITH THE MORE AGGRESSIVE GFS SHOWING H85
TEMPS FALLING AS LO AS -3C AT IWD BY 00Z SUN...MAY CAUSE ANY PCPN TO
AT LEAST MIX WITH SN...BUT THE WEAKER DYNAMIC COOLING AND SFC TEMPS
HOLDING ABV 32 WL PREVENT ANY ACCUMULATION.
TNGT...AS THE SFC LO SHIFTS NE INTO ERN ONTARIO BY 12Z SUN...A
COLDER CYC NNW FLOW WL ENVELOP THE ENTIRE CWA IN ITS WAKE. WITH DEEP
LYR QVECTOR DVGC DOMINATING IN THE CAD/DRYING IN THE WAKE OF THE
SHRTWV...LINGERING PCPN WL SHIFT TO AN LES MODE WITH H85 TEMPS
WITHIN THE TRAILING THERMAL TROF FALLING TO -8C TO -10C /LK WATER
TEMPS ARE 5-6C/ OVER THE W BY 12Z SUN UNDER CYC FLOW/SLOWLY DECAYING
DEEPER MSTR WITHIN THE COMMA HEAD. SINCE THE DGZ IS FCST TO BE
WITHIN THE LARGER SCALE SUBSIDENCE AT THE TOP OF THE MOIST LYR AND
ABV THE SHARPER LLVL CNVGC/FORCING...SUSPECT THIS EVENT WL BE A HI
POP/FAIRLY LO QPF WITH NO NEED FOR HEADLINES ATTM. STILL...A FEW
INCHES OF WET SN ARE LIKELY OVER MAINLY THE HIER TERRAIN IN THE NNW
WIND SN BELTS OF THE W WHERE THE UPSLOPE COOLING/LLVL CNVGC WL BE
MAXIMIZED. ALTHOUGH THE FLOW WL TURN TO THE NW AFT 06Z OVER THE E...
THE AIR WL NOT BE SUFFICIENTLY COLD FOR SGNFT LES THERE THRU 12Z.
CUT POPS SGNFTLY OVER THE SCNTRL WITH EXPECTED DOWNSLOPE NW FLOW IN
THE ABSENCE OF ANY DYNAMIC SUPPORT.
SUN...AS THE H85 THERMAL TROF SHIFTS E FOLLOWING THE DEPARTING SFC
LO...EXPECT LES TO ENVELOP MAINLY THE NNW WIND SN BELTS OVER THE E.
BUT THRU THE DAY...RISING HGTS/MORE ACYC FLOW WL TEND TO DIMINISH
THIS ACTIVITY W-E AS WELL. ANY SN ACCUMULATIONS SHOULD REMAIN ON THE
LGT SIDE WITH POOR SN GROWTH PARAMETERS/DGZ ABV THE RELATIVELY
SHALLOW MSTR/LLVL FORCING IN THE ABSENCE OF DYNAMIC SUPPORT. OTRW...
THE DAY SHOULD FEATURE MORE SEASONABLY CHILLY TEMPS. THE SC WL
SLOWLY BREAK UP...ESPECIALLY OVER THE SCNTRL IN THE PRESENCE OF
DOWNSLOPE FLOW.
SUN NGT...UNDER BLDG UPR RDG...SFC HI PRES RDG AXIS WL SHIFT OVER
THE CWA. LGT WINDS UNDER THIS HI/FCST PWAT 60 PCT OF NORMAL WARRANTS
LOWERING PREVIOUS FCST MIN TEMPS TOWARD THE LO END OF GUIDANCE...
ESPECIALLY OVER THE INTERIOR W AND CNTRL.
MON...WARMER AIR IS FCST TO RETURN WITH STRENGTHENING SW FLOW BTWN
HI PRES SINKING INTO THE LOWER GRT LKS AND NEXT SHRTW/SFC LO
TRACKING INTO NW ONTARIO. H85 TEMPS ARE FCST TO REACH ARND 5C DURING
THE AFTN. THE COLD FNT ATTENDANT TO THE LO WL APRCH THE WRN ZNS LATE
IN THE DAY...BUT RELATIVE DRYNESS OF AIRMASS IN PLACE WITH MSTR
INFLOW DISRUPTED BY DVLPG LO IN THE OH RIVER VALLEY AND PASSAGE OF
STRONGER DYNAMICS FARTHER TO THE N WL MAINTAIN DRY WX.
MON NGT...EXPECT COLD FROPA ATTENDANT TO SHRTWV/SFC LO PASSAGE IN
NRN ONTARIO. HIER RH IS FCST TO STAY TO THE N CLOSER TO SHRTWV
TRACK...SO EXPECT A DRY FROPA. FCST SCHC POPS OVER THE NRN TIER
WHERE VEERING FLOW FM SW TO NW WL RESULT IN SOME UPSLOPE WIND
COMPONENT.
EXTENDED...CWA WL BE DOMINATED BY RELATIVELY DRY NRN BRANCH UPR
FLOW. SO EXPECT NO SGNFT PCPN EVENTS DURING THIS TIME THAT WL LIKELY
FEATURE FAIRLY CHANGEABLE TEMPS. TIMING DIFFERENCES ON SHRTWVS
EMBEDDED WITHIN THE FLOW WARRANTS HOLDING CLOSE TO ALL BLEND FCST.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
LOW PRESSURE NEAR THE WI/MI BORDER WILL DRIFT ACROSS THE AREA THIS
AFTERNOON...THEN MOVE NORTHEAST OF THE AREA TONIGHT. THIS WILL KEEP
LOW CIGS/VSBYS FOR ALL SITES AT LEAST THROUGH THE AFTERNOON BEFORE
SLOW IMPROVEMENT OCCURS TONIGHT AS COLDER/DRIER LOW LEVEL AIR AIR
MOVES IN ON NWLY WINDS. THIS WILL ALLOW FOR CIGS AND VSBYS TO RISE
TO MVFR AT ALL SITES...BUT WILL ALSO CAUSE ANY RAIN TO CHANGE TO
SNOW THIS EVENING...ESPECIALLY AT IWD. EXPECT LIGHT SNOW AT IWD AND
EVENTUALLY AT CMX TO CAUSE OCCASIONAL IFR VSBYS THROUGH SUNDAY
MORNING.
&&
.MARINE /FOR THE 4AM LAKE SUPERIOR FORECAST ISSUANCE/...
A LOW PRESSURE SYSTEM IN MN WILL SLIDE NE TODAY AND ACROSS UPPER
MICHIGAN. THIS WILL PRODUCE EASTERLY WINDS UP TO 30KTS OVER THE NRN
HALF OF LAKE SUPERIOR...WITH A FEW GALE FORCE GUSTS TOP 35KTS NEAR
ISLE ROYALE. AS THE LOW SHIFTS EAST TONIGHT...EXPECT WINDS TO TURN
TO THE NNW. MODELS HAVE TRENDED MUCH WEAKER WITH THE LOW AND THUS
HAVE LIMITED CONFIDENCE IN SEEING WINDS WARRENTING A GALE
WATCH/WARNING. THUS...HAVE DECIDED TO CANCEL THE WATCH SINCE THE
MAIN WINDS WILL BE IN THE 30KT RANGE. BEST CHANCE FOR SOME GALE
FORCE GUSTS WILL COME FROM 09-15Z TONIGHT OVER CENTRAL LAKE SUPERIOR
AND WILL MENTION SOME GUSTS FOR THAT TIME FRAME. WINDS WILL DIMINISH
BELOW 20KTS ON SUN NIGHT DUE TO A WEAK SFC TROUGH. EXPECT ANOTHER
SFC TROUGH TO SLIDE ACROSS LK SUPERIOR ON MONDAY EVENING...WITH ONCE
AGAIN COULD PRODUCE WINDS UP TO 30KTS. CENTRAL LK SUPERIOR COULD
ALSO SEE A FEW GALE FORCE GUSTS TO 35KTS. EXPECT WINDS TO FALL BELOW
25KTS TUES AFTN AND CONTINUE INTO WED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...MRD
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1108 AM EST SAT NOV 26 2011
.UPDATE...
A LITTLE DRYING HAS MOVED INTO THE WESTERN HALF OF UPPER
MICHIGAN...WHICH HELPED TO DECREASE PCPN SOMEWHAT THIS MORNING.
HOWEVER...THE PCPN HAS REDEVELOPED AS ANOTHER WAVE MOVES THROUGH THE
AREA. WITH THIS IN MIND...HAVE OPTED TO KEEP CATEGORICAL POPS ACROSS
THE ENTIRE AREA EXCEPT THE FAR WEST WHERE ADDITIONAL PCPN WILL HAVE
TO WAIT UNTIL WRAP AROUND MOISTURE MOVES IN LATER ON TODAY. AS FOR
PCPN TYPE ACROSS THE FAR WEST...LATEST MODEL SOUNDINGS FROM IWD DO
NOT SHOW THE FREEZING LEVEL LOWERING TO BELOW 1000 FT UNTIL AFTER
00Z. THAT COMBINED WITH THE FACT THAT THE BL TEMPS WILL BE AT LEAST
IN THE MID-UPPER 30S...HAVE OPTED TO REMOVE ANY MENTION OF SNOW
UNTIL THIS EVENING.
&&
PREV DISCUSSION...ISSUED AT 656 AM EST SAT NOV 26 2011...
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR TROFFING OVER
THE PLAINS BTWN PERSISTENT RDG OVER THE ERN CONUS AND ANOTHER RDG
OVER THE W COAST. THERE ARE 3 SHRTWVS OF SIGNIFICANCE EMBEDDED
WITHIN THE TROF OVER THE PLAINS...ONE OVER SASKTATCHEWAN...ANOTHER
IN WYOMING...AND ANOTHER CENTERED NEAR THE TX PANHANDLE. THE COMPLEX
INTERACTION BTWN THESE SEPARATE DISTURBANCES HAS MADE THE EVOLUTION
OF THE UPCOMING WX PATTERN A BIT TRICKY FOR RECENT SHIFTS. THE
DISTURBANCE OVER WYOMING IS SUPPORTING A SFC LO OVER WCNTRL MN. A
FAIRLY WELL DEFINED COMMA CLD IS PRESENT WITH COMMA HEAD PCPN NOTED
UNDER COLDER CLD TOPS OVER THE DAKOTAS ON THE COLD SIDE OF THE
ACCOMPANYING H85 LO. THE WARM CONVEYOR BELT CLD EXTENDS THRU THE UPR
MIDWEST/UPR MS RIVER VALLEY INTO THE GRT LKS...BUT DRY AIR NOTED AT
H7 BY THE BULK OF THE RAOBS...VERY WELL SHOWN BY THE 00Z GRB/MPX
RAOBS...E OF THE UPR TROF AXIS HAS PREVENTED WDSPRD RA FM DVLPG
DESPITE INCRSG UPR DVGC UNDER COUPLED UPR JET STRUCTURE BTWN H3
SPEED MAX IN ONTARIO AND ANOTHER IN SDAKOTA/NEBRASKA. HOWEVER...THE
INTERACTION BTWN THIS DYNAMIC AND THE STRONG SW FLOW E OF THE MN LO
THAT IS ADVECTING UNSEASONABLY HI H85 DWPTS UP TO 6C FROM OMAHA TO
THRU IOWA TOWARD THE UPR MIDWEST HAS CAUSED A RECENT EXPANSION OF
THE RADAR ECHOES TO THE SW. ALTHOUGH A SFC COLD FNT...ASSOCIATED
WITH THE JET MAX IN ONTARIO...HAS SLID OVER UPR MI...TEMPS OVER UPR
MI ARE WELL ABV NORMAL IN THE UPR 30S/40S. THIS FNT HAS PRETTY MUCH
STALLED BUT COULD SERVE AS A FOCAL POINT FOR INCRSG LLVL MSTR CNVGC/
FGEN/ISENTROPIC ASCENT.
&&
.DISCUSSION...
MAIN FCST CONCERNS THRU THIS WEEKEND ARE PCPN CHCS/TYPES/POTENTIAL
SN ACCUMS AND TIMING OF DRYING TREND FOLLOWING THE PASSAGE OF UPR
TROF/SFC LO.
TDAY...RECENT MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON EXPECTED
STRENGTH/TRACK OF SFC LO THAT WL IMPACT THE CWA AHEAD OF DISTURBANCE
NOW IN WYOMING. THIS LO IS PROGGED TO MOVE TO BTWN MQT AND MUNISING
BY 00Z SUN. AS THE SFC LO NOW IN MN MOVES TOWARD UPR MI...GUIDANCE
SHOWS INCRSG ISENTROPIC ASCENT FOCUSED ON THE 290K SFC/UPR DVGC
UNDER FVRBL ORIENTATION OF UPR JET CORES/PWAT SURGING TO ALMOST 250
PCT OF NORMAL WITH THE ARRIVAL OF H85 DWPTS OF 5C. BOTH THE 00Z
NAM/GFS SHOW THE SHARPEST H85-7 FGEN ACCOMPANYING THE FVRBL
INTERACTION BTWN THESE DYNAMICS/MOISTENING AND THE FNTL BNDRY
IMPACTING MAINLY THE NW CWA WITH THE HIEST QPF THEN SHIFTING OUT
OVER LK SUP AND TO THE E IN THE AFTN. ALTHOUGH THE FCST LLVL CYC NNW
FLOW IN THE WAKE OF THE SFC LO PASSING TO THE E WL PROBABLY KEEP
SOME PCPN GOING OVER THE W...FCST DEEP LYR QVECTOR DVGC ARRIVING FM
THE SW IN THE AFTN WL LIKELY LIMIT THE INTENSITY OF THE PCPN THERE
MORE THAN EARLIER ANTICIPATED AND WEAKEN THE COMMA HEAD PCPN NOTED
OVER THE DAKOTAS EARLY THIS MRNG. THE ARRIVAL OF SOMEWHAT COLDER
LLVL AIR INTO THE W LATE...WITH THE MORE AGGRESSIVE GFS SHOWING H85
TEMPS FALLING AS LO AS -3C AT IWD BY 00Z SUN...MAY CAUSE ANY PCPN TO
AT LEAST MIX WITH SN...BUT THE WEAKER DYNAMIC COOLING AND SFC TEMPS
HOLDING ABV 32 WL PREVENT ANY ACCUMULATION.
TNGT...AS THE SFC LO SHIFTS NE INTO ERN ONTARIO BY 12Z SUN...A
COLDER CYC NNW FLOW WL ENVELOP THE ENTIRE CWA IN ITS WAKE. WITH DEEP
LYR QVECTOR DVGC DOMINATING IN THE CAD/DRYING IN THE WAKE OF THE
SHRTWV...LINGERING PCPN WL SHIFT TO AN LES MODE WITH H85 TEMPS
WITHIN THE TRAILING THERMAL TROF FALLING TO -8C TO -10C /LK WATER
TEMPS ARE 5-6C/ OVER THE W BY 12Z SUN UNDER CYC FLOW/SLOWLY DECAYING
DEEPER MSTR WITHIN THE COMMA HEAD. SINCE THE DGZ IS FCST TO BE
WITHIN THE LARGER SCALE SUBSIDENCE AT THE TOP OF THE MOIST LYR AND
ABV THE SHARPER LLVL CNVGC/FORCING...SUSPECT THIS EVENT WL BE A HI
POP/FAIRLY LO QPF WITH NO NEED FOR HEADLINES ATTM. STILL...A FEW
INCHES OF WET SN ARE LIKELY OVER MAINLY THE HIER TERRAIN IN THE NNW
WIND SN BELTS OF THE W WHERE THE UPSLOPE COOLING/LLVL CNVGC WL BE
MAXIMIZED. ALTHOUGH THE FLOW WL TURN TO THE NW AFT 06Z OVER THE E...
THE AIR WL NOT BE SUFFICIENTLY COLD FOR SGNFT LES THERE THRU 12Z.
CUT POPS SGNFTLY OVER THE SCNTRL WITH EXPECTED DOWNSLOPE NW FLOW IN
THE ABSENCE OF ANY DYNAMIC SUPPORT.
SUN...AS THE H85 THERMAL TROF SHIFTS E FOLLOWING THE DEPARTING SFC
LO...EXPECT LES TO ENVELOP MAINLY THE NNW WIND SN BELTS OVER THE E.
BUT THRU THE DAY...RISING HGTS/MORE ACYC FLOW WL TEND TO DIMINISH
THIS ACTIVITY W-E AS WELL. ANY SN ACCUMULATIONS SHOULD REMAIN ON THE
LGT SIDE WITH POOR SN GROWTH PARAMETERS/DGZ ABV THE RELATIVELY
SHALLOW MSTR/LLVL FORCING IN THE ABSENCE OF DYNAMIC SUPPORT. OTRW...
THE DAY SHOULD FEATURE MORE SEASONABLY CHILLY TEMPS. THE SC WL
SLOWLY BREAK UP...ESPECIALLY OVER THE SCNTRL IN THE PRESENCE OF
DOWNSLOPE FLOW.
SUN NGT...UNDER BLDG UPR RDG...SFC HI PRES RDG AXIS WL SHIFT OVER
THE CWA. LGT WINDS UNDER THIS HI/FCST PWAT 60 PCT OF NORMAL WARRANTS
LOWERING PREVIOUS FCST MIN TEMPS TOWARD THE LO END OF GUIDANCE...
ESPECIALLY OVER THE INTERIOR W AND CNTRL.
MON...WARMER AIR IS FCST TO RETURN WITH STRENGTHENING SW FLOW BTWN
HI PRES SINKING INTO THE LOWER GRT LKS AND NEXT SHRTW/SFC LO
TRACKING INTO NW ONTARIO. H85 TEMPS ARE FCST TO REACH ARND 5C DURING
THE AFTN. THE COLD FNT ATTENDANT TO THE LO WL APRCH THE WRN ZNS LATE
IN THE DAY...BUT RELATIVE DRYNESS OF AIRMASS IN PLACE WITH MSTR
INFLOW DISRUPTED BY DVLPG LO IN THE OH RIVER VALLEY AND PASSAGE OF
STRONGER DYNAMICS FARTHER TO THE N WL MAINTAIN DRY WX.
MON NGT...EXPECT COLD FROPA ATTENDANT TO SHRTWV/SFC LO PASSAGE IN
NRN ONTARIO. HIER RH IS FCST TO STAY TO THE N CLOSER TO SHRTWV
TRACK...SO EXPECT A DRY FROPA. FCST SCHC POPS OVER THE NRN TIER
WHERE VEERING FLOW FM SW TO NW WL RESULT IN SOME UPSLOPE WIND
COMPONENT.
EXTENDED...CWA WL BE DOMINATED BY RELATIVELY DRY NRN BRANCH UPR
FLOW. SO EXPECT NO SGNFT PCPN EVENTS DURING THIS TIME THAT WL LIKELY
FEATURE FAIRLY CHANGEABLE TEMPS. TIMING DIFFERENCES ON SHRTWVS
EMBEDDED WITHIN THE FLOW WARRANTS HOLDING CLOSE TO ALL BLEND FCST.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
A LOW PRESSURE SYSTEM MOVING ACROSS UPPER MICHIGAN TODAY WILL BRING
RAIN TO ALL THREE TAF SITES. AS HAS BEEN THE CASE OVER THE LAST
SEVERAL DAYS...LOW CLOUDS EXPECTED TO INFLUENCE THE AREA. KIWD HAS
BEEN BUCKING THE TREND WITH VFR CIGS UNDER LIGHT ERLY FLOW...BUT
ADDITIONAL RAIN AND LLVL MOISTURE MOVING INTO THE SITE SHOULD PULL
CIGS/VSBY TO IFR. FAVORABLE ESE FLOW AT BOTH KCMX/KSAW WILL LEAD TO
VLIFR CONDITIONS THROUGH MUCH OF THE DAY...ALTHOUGH MIXING FROM
STRONGER RAIN SHOWERS COULD PROVIDE A BRIEF REPRIEVE. AS THE LOW
SHIFTS E TONIGHT...EXPECT WINDS TO INCREASE OUT OF THE NW AND TRY TO
PULL IN DRIER LLVL AIR. THUS...HAVE SHOWED A IMPROVING TREND WITH
CIGS/VSBYS.
&&
.MARINE /FOR THE 4AM LAKE SUPERIOR FORECAST ISSUANCE/...
A LOW PRESSURE SYSTEM IN MN WILL SLIDE NE TODAY AND ACROSS UPPER
MICHIGAN. THIS WILL PRODUCE EASTERLY WINDS UP TO 30KTS OVER THE NRN
HALF OF LAKE SUPERIOR...WITH A FEW GALE FORCE GUSTS TOP 35KTS NEAR
ISLE ROYALE. AS THE LOW SHIFTS EAST TONIGHT...EXPECT WINDS TO TURN
TO THE NNW. MODELS HAVE TRENDED MUCH WEAKER WITH THE LOW AND THUS
HAVE LIMITED CONFIDENCE IN SEEING WINDS WARRENTING A GALE
WATCH/WARNING. THUS...HAVE DECIDED TO CANCEL THE WATCH SINCE THE
MAIN WINDS WILL BE IN THE 30KT RANGE. BEST CHANCE FOR SOME GALE
FORCE GUSTS WILL COME FROM 09-15Z TONIGHT OVER CENTRAL LAKE SUPERIOR
AND WILL MENTION SOME GUSTS FOR THAT TIME FRAME. WINDS WILL DIMINISH
BELOW 20KTS ON SUN NIGHT DUE TO A WEAK SFC TROUGH. EXPECT ANOTHER
SFC TROUGH TO SLIDE ACROSS LK SUPERIOR ON MONDAY EVENING...WITH ONCE
AGAIN COULD PRODUCE WINDS UP TO 30KTS. CENTRAL LK SUPERIOR COULD
ALSO SEE A FEW GALE FORCE GUSTS TO 35KTS. EXPECT WINDS TO FALL BELOW
25KTS TUES AFTN AND CONTINUE INTO WED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
DISCUSSION...KC
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
656 AM EST SAT NOV 26 2011
UPDATED AVIATION DISCUSSION FOR 12Z TAFS
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR TROFFING OVER
THE PLAINS BTWN PERSISTENT RDG OVER THE ERN CONUS AND ANOTHER RDG
OVER THE W COAST. THERE ARE 3 SHRTWVS OF SIGNIFICANCE EMBEDDED
WITHIN THE TROF OVER THE PLAINS...ONE OVER SASKTATCHEWAN...ANOTHER
IN WYOMING...AND ANOTHER CENTERED NEAR THE TX PANHANDLE. THE COMPLEX
INTERACTION BTWN THESE SEPARATE DISTURBANCES HAS MADE THE EVOLUTION
OF THE UPCOMING WX PATTERN A BIT TRICKY FOR RECENT SHIFTS. THE
DISTURBANCE OVER WYOMING IS SUPPORTING A SFC LO OVER WCNTRL MN. A
FAIRLY WELL DEFINED COMMA CLD IS PRESENT WITH COMMA HEAD PCPN NOTED
UNDER COLDER CLD TOPS OVER THE DAKOTAS ON THE COLD SIDE OF THE
ACCOMPANYING H85 LO. THE WARM CONVEYOR BELT CLD EXTENDS THRU THE UPR
MIDWEST/UPR MS RIVER VALLEY INTO THE GRT LKS...BUT DRY AIR NOTED AT
H7 BY THE BULK OF THE RAOBS...VERY WELL SHOWN BY THE 00Z GRB/MPX
RAOBS...E OF THE UPR TROF AXIS HAS PREVENTED WDSPRD RA FM DVLPG
DESPITE INCRSG UPR DVGC UNDER COUPLED UPR JET STRUCTURE BTWN H3
SPEED MAX IN ONTARIO AND ANOTHER IN SDAKOTA/NEBRASKA. HOWEVER...THE
INTERACTION BTWN THIS DYNAMIC AND THE STRONG SW FLOW E OF THE MN LO
THAT IS ADVECTING UNSEASONABLY HI H85 DWPTS UP TO 6C FROM OMAHA TO
THRU IOWA TOWARD THE UPR MIDWEST HAS CAUSED A RECENT EXPANSION OF
THE RADAR ECHOES TO THE SW. ALTHOUGH A SFC COLD FNT...ASSOCIATED
WITH THE JET MAX IN ONTARIO...HAS SLID OVER UPR MI...TEMPS OVER UPR
MI ARE WELL ABV NORMAL IN THE UPR 30S/40S. THIS FNT HAS PRETTY MUCH
STALLED BUT COULD SERVE AS A FOCAL POINT FOR INCRSG LLVL MSTR CNVGC/
FGEN/ISENTROPIC ASCENT.
&&
.DISCUSSION...
MAIN FCST CONCERNS THRU THIS WEEKEND ARE PCPN CHCS/TYPES/POTENTIAL
SN ACCUMS AND TIMING OF DRYING TREND FOLLOWING THE PASSAGE OF UPR
TROF/SFC LO.
TDAY...RECENT MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON EXPECTED
STRENGTH/TRACK OF SFC LO THAT WL IMPACT THE CWA AHEAD OF DISTURBANCE
NOW IN WYOMING. THIS LO IS PROGGED TO MOVE TO BTWN MQT AND MUNISING
BY 00Z SUN. AS THE SFC LO NOW IN MN MOVES TOWARD UPR MI...GUIDANCE
SHOWS INCRSG ISENTROPIC ASCENT FOCUSED ON THE 290K SFC/UPR DVGC
UNDER FVRBL ORIENTATION OF UPR JET CORES/PWAT SURGING TO ALMOST 250
PCT OF NORMAL WITH THE ARRIVAL OF H85 DWPTS OF 5C. BOTH THE 00Z
NAM/GFS SHOW THE SHARPEST H85-7 FGEN ACCOMPANYING THE FVRBL
INTERACTION BTWN THESE DYNAMICS/MOISTENING AND THE FNTL BNDRY
IMPACTING MAINLY THE NW CWA WITH THE HIEST QPF THEN SHIFTING OUT
OVER LK SUP AND TO THE E IN THE AFTN. ALTHOUGH THE FCST LLVL CYC NNW
FLOW IN THE WAKE OF THE SFC LO PASSING TO THE E WL PROBABLY KEEP
SOME PCPN GOING OVER THE W...FCST DEEP LYR QVECTOR DVGC ARRIVING FM
THE SW IN THE AFTN WL LIKELY LIMIT THE INTENSITY OF THE PCPN THERE
MORE THAN EARLIER ANTICIPATED AND WEAKEN THE COMMA HEAD PCPN NOTED
OVER THE DAKOTAS EARLY THIS MRNG. THE ARRIVAL OF SOMEWHAT COLDER
LLVL AIR INTO THE W LATE...WITH THE MORE AGGRESSIVE GFS SHOWING H85
TEMPS FALLING AS LO AS -3C AT IWD BY 00Z SUN...MAY CAUSE ANY PCPN TO
AT LEAST MIX WITH SN...BUT THE WEAKER DYNAMIC COOLING AND SFC TEMPS
HOLDING ABV 32 WL PREVENT ANY ACCUMULATION.
TNGT...AS THE SFC LO SHIFTS NE INTO ERN ONTARIO BY 12Z SUN...A
COLDER CYC NNW FLOW WL ENVELOP THE ENTIRE CWA IN ITS WAKE. WITH DEEP
LYR QVECTOR DVGC DOMINATING IN THE CAD/DRYING IN THE WAKE OF THE
SHRTWV...LINGERING PCPN WL SHIFT TO AN LES MODE WITH H85 TEMPS
WITHIN THE TRAILING THERMAL TROF FALLING TO -8C TO -10C /LK WATER
TEMPS ARE 5-6C/ OVER THE W BY 12Z SUN UNDER CYC FLOW/SLOWLY DECAYING
DEEPER MSTR WITHIN THE COMMA HEAD. SINCE THE DGZ IS FCST TO BE
WITHIN THE LARGER SCALE SUBSIDENCE AT THE TOP OF THE MOIST LYR AND
ABV THE SHARPER LLVL CNVGC/FORCING...SUSPECT THIS EVENT WL BE A HI
POP/FAIRLY LO QPF WITH NO NEED FOR HEADLINES ATTM. STILL...A FEW
INCHES OF WET SN ARE LIKELY OVER MAINLY THE HIER TERRAIN IN THE NNW
WIND SN BELTS OF THE W WHERE THE UPSLOPE COOLING/LLVL CNVGC WL BE
MAXIMIZED. ALTHOUGH THE FLOW WL TURN TO THE NW AFT 06Z OVER THE E...
THE AIR WL NOT BE SUFFICIENTLY COLD FOR SGNFT LES THERE THRU 12Z.
CUT POPS SGNFTLY OVER THE SCNTRL WITH EXPECTED DOWNSLOPE NW FLOW IN
THE ABSENCE OF ANY DYNAMIC SUPPORT.
SUN...AS THE H85 THERMAL TROF SHIFTS E FOLLOWING THE DEPARTING SFC
LO...EXPECT LES TO ENVELOP MAINLY THE NNW WIND SN BELTS OVER THE E.
BUT THRU THE DAY...RISING HGTS/MORE ACYC FLOW WL TEND TO DIMINISH
THIS ACTIVITY W-E AS WELL. ANY SN ACCUMULATIONS SHOULD REMAIN ON THE
LGT SIDE WITH POOR SN GROWTH PARAMETERS/DGZ ABV THE RELATIVELY
SHALLOW MSTR/LLVL FORCING IN THE ABSENCE OF DYNAMIC SUPPORT. OTRW...
THE DAY SHOULD FEATURE MORE SEASONABLY CHILLY TEMPS. THE SC WL
SLOWLY BREAK UP...ESPECIALLY OVER THE SCNTRL IN THE PRESENCE OF
DOWNSLOPE FLOW.
SUN NGT...UNDER BLDG UPR RDG...SFC HI PRES RDG AXIS WL SHIFT OVER
THE CWA. LGT WINDS UNDER THIS HI/FCST PWAT 60 PCT OF NORMAL WARRANTS
LOWERING PREVIOUS FCST MIN TEMPS TOWARD THE LO END OF GUIDANCE...
ESPECIALLY OVER THE INTERIOR W AND CNTRL.
MON...WARMER AIR IS FCST TO RETURN WITH STRENGTHENING SW FLOW BTWN
HI PRES SINKING INTO THE LOWER GRT LKS AND NEXT SHRTW/SFC LO
TRACKING INTO NW ONTARIO. H85 TEMPS ARE FCST TO REACH ARND 5C DURING
THE AFTN. THE COLD FNT ATTENDANT TO THE LO WL APRCH THE WRN ZNS LATE
IN THE DAY...BUT RELATIVE DRYNESS OF AIRMASS IN PLACE WITH MSTR
INFLOW DISRUPTED BY DVLPG LO IN THE OH RIVER VALLEY AND PASSAGE OF
STRONGER DYNAMICS FARTHER TO THE N WL MAINTAIN DRY WX.
MON NGT...EXPECT COLD FROPA ATTENDANT TO SHRTWV/SFC LO PASSAGE IN
NRN ONTARIO. HIER RH IS FCST TO STAY TO THE N CLOSER TO SHRTWV
TRACK...SO EXPECT A DRY FROPA. FCST SCHC POPS OVER THE NRN TIER
WHERE VEERING FLOW FM SW TO NW WL RESULT IN SOME UPSLOPE WIND
COMPONENT.
EXTENDED...CWA WL BE DOMINATED BY RELATIVELY DRY NRN BRANCH UPR
FLOW. SO EXPECT NO SGNFT PCPN EVENTS DURING THIS TIME THAT WL LIKELY
FEATURE FAIRLY CHANGEABLE TEMPS. TIMING DIFFERENCES ON SHRTWVS
EMBEDDED WITHIN THE FLOW WARRANTS HOLDING CLOSE TO ALL BLEND FCST.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
A LOW PRESSURE SYSTEM MOVING ACROSS UPPER MICHIGAN TODAY WILL BRING
RAIN TO ALL THREE TAF SITES. AS HAS BEEN THE CASE OVER THE LAST
SEVERAL DAYS...LOW CLOUDS EXPECTED TO INFLUENCE THE AREA. KIWD HAS
BEEN BUCKING THE TREND WITH VFR CIGS UNDER LIGHT ERLY FLOW...BUT
ADDITIONAL RAIN AND LLVL MOISTURE MOVING INTO THE SITE SHOULD PULL
CIGS/VSBY TO IFR. FAVORABLE ESE FLOW AT BOTH KCMX/KSAW WILL LEAD TO
VLIFR CONDITIONS THROUGH MUCH OF THE DAY...ALTHOUGH MIXING FROM
STRONGER RAIN SHOWERS COULD PROVIDE A BRIEF REPRIEVE. AS THE LOW
SHIFTS E TONIGHT...EXPECT WINDS TO INCREASE OUT OF THE NW AND TRY TO
PULL IN DRIER LLVL AIR. THUS...HAVE SHOWED A IMPROVING TREND WITH
CIGS/VSBYS.
&&
.MARINE /FOR THE 4AM LAKE SUPERIOR FORECAST ISSUANCE/...
A LOW PRESSURE SYSTEM IN MN WILL SLIDE NE TODAY AND ACROSS UPPER
MICHIGAN. THIS WILL PRODUCE EASTERLY WINDS UP TO 30KTS OVER THE NRN
HALF OF LAKE SUPERIOR...WITH A FEW GALE FORCE GUSTS TOP 35KTS NEAR
ISLE ROYALE. AS THE LOW SHIFTS EAST TONIGHT...EXPECT WINDS TO TURN
TO THE NNW. MODELS HAVE TRENDED MUCH WEAKER WITH THE LOW AND THUS
HAVE LIMITED CONFIDENCE IN SEEING WINDS WARRENTING A GALE
WATCH/WARNING. THUS...HAVE DECIDED TO CANCEL THE WATCH SINCE THE
MAIN WINDS WILL BE IN THE 30KT RANGE. BEST CHANCE FOR SOME GALE
FORCE GUSTS WILL COME FROM 09-15Z TONIGHT OVER CENTRAL LAKE SUPERIOR
AND WILL MENTION SOME GUSTS FOR THAT TIME FRAME. WINDS WILL DIMINISH
BELOW 20KTS ON SUN NIGHT DUE TO A WEAK SFC TROUGH. EXPECT ANOTHER
SFC TROUGH TO SLIDE ACROSS LK SUPERIOR ON MONDAY EVENING...WITH ONCE
AGAIN COULD PRODUCE WINDS UP TO 30KTS. CENTRAL LK SUPERIOR COULD
ALSO SEE A FEW GALE FORCE GUSTS TO 35KTS. EXPECT WINDS TO FALL BELOW
25KTS TUES AFTN AND CONTINUE INTO WED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
414 AM EST SAT NOV 26 2011
.SYNOPSIS...
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR TROFFING OVER
THE PLAINS BTWN PERSISTENT RDG OVER THE ERN CONUS AND ANOTHER RDG
OVER THE W COAST. THERE ARE 3 SHRTWVS OF SIGNIFICANCE EMBEDDED
WITHIN THE TROF OVER THE PLAINS...ONE OVER SASKTATCHEWAN...ANOTHER
IN WYOMING...AND ANOTHER CENTERED NEAR THE TX PANHANDLE. THE COMPLEX
INTERACTION BTWN THESE SEPARATE DISTURBANCES HAS MADE THE EVOLUTION
OF THE UPCOMING WX PATTERN A BIT TRICKY FOR RECENT SHIFTS. THE
DISTURBANCE OVER WYOMING IS SUPPORTING A SFC LO OVER WCNTRL MN. A
FAIRLY WELL DEFINED COMMA CLD IS PRESENT WITH COMMA HEAD PCPN NOTED
UNDER COLDER CLD TOPS OVER THE DAKOTAS ON THE COLD SIDE OF THE
ACCOMPANYING H85 LO. THE WARM CONVEYOR BELT CLD EXTENDS THRU THE UPR
MIDWEST/UPR MS RIVER VALLEY INTO THE GRT LKS...BUT DRY AIR NOTED AT
H7 BY THE BULK OF THE RAOBS...VERY WELL SHOWN BY THE 00Z GRB/MPX
RAOBS...E OF THE UPR TROF AXIS HAS PREVENTED WDSPRD RA FM DVLPG
DESPITE INCRSG UPR DVGC UNDER COUPLED UPR JET STRUCTURE BTWN H3
SPEED MAX IN ONTARIO AND ANOTHER IN SDAKOTA/NEBRASKA. HOWEVER...THE
INTERACTION BTWN THIS DYNAMIC AND THE STRONG SW FLOW E OF THE MN LO
THAT IS ADVECTING UNSEASONABLY HI H85 DWPTS UP TO 6C FROM OMAHA TO
THRU IOWA TOWARD THE UPR MIDWEST HAS CAUSED A RECENT EXPANSION OF
THE RADAR ECHOES TO THE SW. ALTHOUGH A SFC COLD FNT...ASSOCIATED
WITH THE JET MAX IN ONTARIO...HAS SLID OVER UPR MI...TEMPS OVER UPR
MI ARE WELL ABV NORMAL IN THE UPR 30S/40S. THIS FNT HAS PRETTY MUCH
STALLED BUT COULD SERVE AS A FOCAL POINT FOR INCRSG LLVL MSTR CNVGC/
FGEN/ISENTROPIC ASCENT.
&&
.DISCUSSION...
MAIN FCST CONCERNS THRU THIS WEEKEND ARE PCPN CHCS/TYPES/POTENTIAL
SN ACCUMS AND TIMING OF DRYING TREND FOLLOWING THE PASSAGE OF UPR
TROF/SFC LO.
TDAY...RECENT MODEL RUNS HAVE COME INTO BETTER AGREEMENT ON EXPECTED
STRENGTH/TRACK OF SFC LO THAT WL IMPACT THE CWA AHEAD OF DISTURBANCE
NOW IN WYOMING. THIS LO IS PROGGED TO MOVE TO BTWN MQT AND MUNISING
BY 00Z SUN. AS THE SFC LO NOW IN MN MOVES TOWARD UPR MI...GUIDANCE
SHOWS INCRSG ISENTROPIC ASCENT FOCUSED ON THE 290K SFC/UPR DVGC
UNDER FVRBL ORIENTATION OF UPR JET CORES/PWAT SURGING TO ALMOST 250
PCT OF NORMAL WITH THE ARRIVAL OF H85 DWPTS OF 5C. BOTH THE 00Z
NAM/GFS SHOW THE SHARPEST H85-7 FGEN ACCOMPANYING THE FVRBL
INTERACTION BTWN THESE DYNAMICS/MOISTENING AND THE FNTL BNDRY
IMPACTING MAINLY THE NW CWA WITH THE HIEST QPF THEN SHIFTING OUT
OVER LK SUP AND TO THE E IN THE AFTN. ALTHOUGH THE FCST LLVL CYC NNW
FLOW IN THE WAKE OF THE SFC LO PASSING TO THE E WL PROBABLY KEEP
SOME PCPN GOING OVER THE W...FCST DEEP LYR QVECTOR DVGC ARRIVING FM
THE SW IN THE AFTN WL LIKELY LIMIT THE INTENSITY OF THE PCPN THERE
MORE THAN EARLIER ANTICIPATED AND WEAKEN THE COMMA HEAD PCPN NOTED
OVER THE DAKOTAS EARLY THIS MRNG. THE ARRIVAL OF SOMEWHAT COLDER
LLVL AIR INTO THE W LATE...WITH THE MORE AGGRESSIVE GFS SHOWING H85
TEMPS FALLING AS LO AS -3C AT IWD BY 00Z SUN...MAY CAUSE ANY PCPN TO
AT LEAST MIX WITH SN...BUT THE WEAKER DYNAMIC COOLING AND SFC TEMPS
HOLDING ABV 32 WL PREVENT ANY ACCUMULATION.
TNGT...AS THE SFC LO SHIFTS NE INTO ERN ONTARIO BY 12Z SUN...A
COLDER CYC NNW FLOW WL ENVELOP THE ENTIRE CWA IN ITS WAKE. WITH DEEP
LYR QVECTOR DVGC DOMINATING IN THE CAD/DRYING IN THE WAKE OF THE
SHRTWV...LINGERING PCPN WL SHIFT TO AN LES MODE WITH H85 TEMPS
WITHIN THE TRAILING THERMAL TROF FALLING TO -8C TO -10C /LK WATER
TEMPS ARE 5-6C/ OVER THE W BY 12Z SUN UNDER CYC FLOW/SLOWLY DECAYING
DEEPER MSTR WITHIN THE COMMA HEAD. SINCE THE DGZ IS FCST TO BE
WITHIN THE LARGER SCALE SUBSIDENCE AT THE TOP OF THE MOIST LYR AND
ABV THE SHARPER LLVL CNVGC/FORCING...SUSPECT THIS EVENT WL BE A HI
POP/FAIRLY LO QPF WITH NO NEED FOR HEADLINES ATTM. STILL...A FEW
INCHES OF WET SN ARE LIKELY OVER MAINLY THE HIER TERRAIN IN THE NNW
WIND SN BELTS OF THE W WHERE THE UPSLOPE COOLING/LLVL CNVGC WL BE
MAXIMIZED. ALTHOUGH THE FLOW WL TURN TO THE NW AFT 06Z OVER THE E...
THE AIR WL NOT BE SUFFICIENTLY COLD FOR SGNFT LES THERE THRU 12Z.
CUT POPS SGNFTLY OVER THE SCNTRL WITH EXPECTED DOWNSLOPE NW FLOW IN
THE ABSENCE OF ANY DYNAMIC SUPPORT.
SUN...AS THE H85 THERMAL TROF SHIFTS E FOLLOWING THE DEPARTING SFC
LO...EXPECT LES TO ENVELOP MAINLY THE NNW WIND SN BELTS OVER THE E.
BUT THRU THE DAY...RISING HGTS/MORE ACYC FLOW WL TEND TO DIMINISH
THIS ACTIVITY W-E AS WELL. ANY SN ACCUMULATIONS SHOULD REMAIN ON THE
LGT SIDE WITH POOR SN GROWTH PARAMETERS/DGZ ABV THE RELATIVELY
SHALLOW MSTR/LLVL FORCING IN THE ABSENCE OF DYNAMIC SUPPORT. OTRW...
THE DAY SHOULD FEATURE MORE SEASONABLY CHILLY TEMPS. THE SC WL
SLOWLY BREAK UP...ESPECIALLY OVER THE SCNTRL IN THE PRESENCE OF
DOWNSLOPE FLOW.
SUN NGT...UNDER BLDG UPR RDG...SFC HI PRES RDG AXIS WL SHIFT OVER
THE CWA. LGT WINDS UNDER THIS HI/FCST PWAT 60 PCT OF NORMAL WARRANTS
LOWERING PREVIOUS FCST MIN TEMPS TOWARD THE LO END OF GUIDANCE...
ESPECIALLY OVER THE INTERIOR W AND CNTRL.
MON...WARMER AIR IS FCST TO RETURN WITH STRENGTHENING SW FLOW BTWN
HI PRES SINKING INTO THE LOWER GRT LKS AND NEXT SHRTW/SFC LO
TRACKING INTO NW ONTARIO. H85 TEMPS ARE FCST TO REACH ARND 5C DURING
THE AFTN. THE COLD FNT ATTENDANT TO THE LO WL APRCH THE WRN ZNS LATE
IN THE DAY...BUT RELATIVE DRYNESS OF AIRMASS IN PLACE WITH MSTR
INFLOW DISRUPTED BY DVLPG LO IN THE OH RIVER VALLEY AND PASSAGE OF
STRONGER DYNAMICS FARTHER TO THE N WL MAINTAIN DRY WX.
MON NGT...EXPECT COLD FROPA ATTENDANT TO SHRTWV/SFC LO PASSAGE IN
NRN ONTARIO. HIER RH IS FCST TO STAY TO THE N CLOSER TO SHRTWV
TRACK...SO EXPECT A DRY FROPA. FCST SCHC POPS OVER THE NRN TIER
WHERE VEERING FLOW FM SW TO NW WL RESULT IN SOME UPSLOPE WIND
COMPONENT.
EXTENDED...CWA WL BE DOMINATED BY RELATIVELY DRY NRN BRANCH UPR
FLOW. SO EXPECT NO SGNFT PCPN EVENTS DURING THIS TIME THAT WL LIKELY
FEATURE FAIRLY CHANGEABLE TEMPS. TIMING DIFFERENCES ON SHRTWVS
EMBEDDED WITHIN THE FLOW WARRANTS HOLDING CLOSE TO ALL BLEND FCST.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
TAF FCSTS WILL CONTINUE TO BE A CHALLENGE. IT APPEARS UPSLOPE LIFR
TO VLIFR STRATUS IS BEGINNING TO TAKE SHAPE AT KCMX AND KSAW SO
EXPECT THESE CONDITIONS TO CONTINUE INTO SAT MORNING PERHAPS EVEN
ENHANCED BY INCOMING RAIN FM SYSTEM MOVING UP FM THE CENTRAL PLAINS.
KIWD WILL STAY AT MVFR/IFR UNTIL RAIN MOVES IN LATE TONIGHT AND THEN
I WOULD EXPECT A TREND TOWARD LIFR THERE INTO SAT MORNING.
CONDITIONS WILL MODESTLY IMPROVE TO IFR AT ALL SITES TOWARD EVENING
FROM WEST TO EAST WITH ADVECTION OF DRIER DEWPOINTS BEHIND SYSTEM/S
ASSOC COLD FRONT. SCT SHRA WILL CHANGE TO SCT SHSN AT KIWD AROUND
00Z AND THEN AT KCMX AND KSAW LATER IN THE EVENING.
&&
.MARINE /FOR THE 4AM LAKE SUPERIOR FORECAST ISSUANCE/...
A LOW PRESSURE SYSTEM IN MN WILL SLIDE NE TODAY AND ACROSS UPPER
MICHIGAN. THIS WILL PRODUCE EASTERLY WINDS UP TO 30KTS OVER THE NRN
HALF OF LAKE SUPERIOR...WITH A FEW GALE FORCE GUSTS TOP 35KTS NEAR
ISLE ROYALE. AS THE LOW SHIFTS EAST TONIGHT...EXPECT WINDS TO TURN
TO THE NNW. MODELS HAVE TRENDED MUCH WEAKER WITH THE LOW AND THUS
HAVE LIMITED CONFIDENCE IN SEEING WINDS WARRENTING A GALE
WATCH/WARNING. THUS...HAVE DECIDED TO CANCEL THE WATCH SINCE THE
MAIN WINDS WILL BE IN THE 30KT RANGE. BEST CHANCE FOR SOME GALE
FORCE GUSTS WILL COME FROM 09-15Z TONIGHT OVER CENTRAL LAKE SUPERIOR
AND WILL MENTION SOME GUSTS FOR THAT TIME FRAME. WINDS WILL DIMINISH
BELOW 20KTS ON SUN NIGHT DUE TO A WEAK SFC TROUGH. EXPECT ANOTHER
SFC TROUGH TO SLIDE ACROSS LK SUPERIOR ON MONDAY EVENING...WITH ONCE
AGAIN COULD PRODUCE WINDS UP TO 30KTS. CENTRAL LK SUPERIOR COULD
ALSO SEE A FEW GALE FORCE GUSTS TO 35KTS. EXPECT WINDS TO FALL BELOW
25KTS TUES AFTN AND CONTINUE INTO WED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
DISCUSSION...KC
AVIATION...VOSS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
611 PM CST SUN NOV 27 2011
.UPDATE...
UPDATED FOR AVIATION DISCUSSION BELOW.
&&
.DISCUSSION...
/ISSUED 346 PM CST SUN NOV 27 2011/
SUMMARY...LARGELY DRY FORECAST WITH ONLY SMALL POPS IN THE
FORECAST FOR THURSDAY AND NEXT SUNDAY. THREE COLD FRONTS MOVE
THROUGH OVER THE NEXT 7 DAYS...MONDAY NIGHT...WEDNESDAY
NIGHT...AND SATURDAY NIGHT. SLIGHTLY ABOVE NORMAL TEMPS ARE
EXPECTED AHEAD OF THESE BOUNDARIES MONDAY...WEDNESDAY AND
SATURDAY. NEAR NORMAL OR SLIGHTLY BELOW NORMALS TEMPS ARE
EXPECTED BEHIND THE FRONTAL PASSAGES ON TUESDAY...
THURSDAY...FRIDAY AND SUNDAY.
TONIGHT AND TOMORROW...TRICKY TEMP FORECAST: STRATUS DECK HAS BEEN
VERY SLOW TO CLEAR TODAY AND CONTINUES MOVING TO THE EAST AT JUST
7KTS. WITHIN THE LAST HOUR OR SO...WE`RE FINALLY SEEING SOME
THINNING OF THE DECK IN MN. THIS MIGHT BE A SIGN THAT THE CLEARING
IS A BIT FASTER THAN WHAT`S IN THE FORECAST FOR TONIGHT.
HOWEVER...WE WILL LOSE OUR SUN HERE IN THE NEXT COUPLE HOURS...SO
KEPT THE SLOW CLEARING TREND IN THE FORECAST TONIGHT. MIGHT HAVE
TO WAIT FOR THE RIDGE AXIS TO PASS OVERHEAD...WHICH WOULD MATCH UP
FAIRLY WELL WITH THE 925MB RH OFF THE RUC THIS EVENING. THE CLOUDS
WILL OBVIOUSLY HAVE LARGE IMPACT ON THE TEMPERATURES TONIGHT. KEPT
WEST CENTRAL WI IN THE MID 20S AND EVEN LEFT MOST OF THE METRO IN
THE LOWER TO MID 20S. AREAS THAT GET AT LEAST 3-4 HOURS OF CLEAR
SKIES TOMORROW MORNING...WILL LIKELY GET INTO THE TEENS FOR LOWS.
OTHERWISE...THE MERCURY WILL BE HEADING THE OTHER WAY TOMORROW WITH
WARM AIR ADVECTION KICKING IN BETWEEN 06-12Z TONIGHT. SOUTHWEST
WINDS WITH MIXING UP TO 975-925MB OFF THE FORECAST SOUNDINGS WOULD
GIVE US LOW TO MID 40S ALMOST EVERYWHERE TOMORROW. IN
FACT...DOWNSLOPING OFF THE BUFFALO RIDGE IN WESTERN MN SHOULD
YIELD 50S FOR HIGHS. COLD FRONT PASSES THROUGH FROM NW TO SE LATE
TOMORROW AFTERNOON AND TOMORROW EVENING. MIGHT BE A MID DECK OF
CLOUDS WITH THE FRONT BUT NO PRECIPITATION IS EXPECTED.
TUESDAY THROUGH THURSDAY...-4 TO -6 C AT 850MB INDICATING A COOL
DOWN FOR TUESDAY BEHIND THE FRONT BUT CERTAINLY NOTHING OUT OF THE
ORDINARY. THE COOL DOWN WILL BE BRIEF WITH 1000-500MB THICKNESS
ALREADY CLIMBING BETWEEN 540M-546M EARLY WEDNESDAY. ANOTHER FRONT
MOVES THROUGH WEDNESDAY NIGHT AND WITH THIS BOUNDARY THERE MIGHT
BE JUST ENOUGH FORCING AND MOISTURE TO SHAKE OUT A FEW SNOW FLAKES
IN THE STRATO CUMULUS IN THE WAKE OF THE FRONT ON THURSDAY. BOTH
THE 27.12Z GFS/ECMWF HAVE A FEW TENTHS OF SNOW ACCUMULATION ACROSS
CENTRAL MN AND WESTERN WI.
EXTENDED...NO MAJOR SYSTEMS OUT ON THE HORIZON. WOULDN`T BE
SURPRISED IF WE END UP WITH A LITTLE PRECIP NEXT SUNDAY BASED ON
THE PATTERN INDICATED BY THE ECMWF AND TO A LESSER DEGREE THE
LATEST GFS ENSEMBLE. CPC IS FORECASTING BELOW NORMAL TEMPERATURES
FOR MUCH OF THE COUNTRY IN THE 6-14 DAY OUTLOOKS. ALTHOUGH THE
SIGNAL ISN`T QUITE AS STRONG IN MN/WI...IT FINALLY APPEARS WE
SHOULD GET INTO A MORE WINTER-LIKE AIR MASS AFTER NEXT WEEKEND.
&&
.AVIATION.../00Z TAF ISSUANCE/
CONCERN CONTINUES TO BE THE WESTERN EDGE OF THE LARGE MVFR STRATUS
DECK OVER MN/WI. THIS BACK EDGE HAS ADVANCED TO WITHIN A FEW MILES
OF KAXN AND KRWF...AND BOTH SITES SHOULD GO SCATTERED 01Z-02Z.
FARTHER EAST...RIDGE SLOWLY MOVING EAST. LATEST RUC AND 18Z NAM
BOTH INDICATE CYCLONICALLY CURVED STREAMLINES AT ABOUT 3000 FEET
AGL SHOULD FINALLY MOVE EAST OF KSTC AROUND 04Z FOLLOWED BY
KMSP...KRNH AND LASTLY KEAU AFTER MIDNIGHT. THIS WILL END THE MVFR
CEILINGS. MIGHT TAKE UNTIL 09Z FOR KEAU TO LOSE THE MVFR CEILINGS.
ONCE RIDGE MOVES BY...SURFACE PRESSURE GRADIENT TIGHTENS IN WRN MN
WITH SOUTHERLY WINDS. COLD FRONT ARRIVES IN WEST CENTRAL MN MONDAY
AFTERNOON AND WESTERN WISC MONDAY EVENING.
KMSP...OVERCAST CEILINGS AROUND 2000 FEET AGL THIS EVENING. MAY
BE A BIT OF BROKEN CONDITIONS BUT WILL NEED TO WAIT UNTIL 05Z OR
SO UNTIL IT GOES SCATTERED. SOME POSSIBILITY MVFR CEILINGS WILL
PERSIST BEYOND 05Z AS RUC CONTINUES TO SLOW THINGS DOWN SLIGHTLY.
THEREAFTER LITTLE SIGNIFICANT WEATHER UNTIL COLD FRONT ARRIVES
MONDAY EVENING WHEN THERE WILL BE A DECENT POTENTIAL FOR MORE MVFR
CEILINGS IN COLD ADVECTION.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
CLF/TDK
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1218 PM CST SAT NOV 26 2011
.UPDATE...MIDDDAY SURFACE ANALYSIS INDICATES HIGH PRESSURE OVER
THE ROCKY MOUNTAIN RANGE...WITH VERY INTENSE LOW LEVEL PRESSURE
RISES IN PROCESS ACROSS THE CENTRAL PLAINS. STRONG
NORTH/NORTHWESTERLY LOW LEVEL FLOW HAS ESTABLISHED ITSELF ACROSS
THE REGION AS A RESULT. SHORT TERM GUIDANCE CONTINUES TO SUGGEST
THE LOW LEVEL PRESSURE GRADIENT WILL REMAIN VERY STRONG THROUGH
THIS AFTERNOON...THUS PROMOTING STRONG WINDS THROUGH THE REMAINDER
OF THE AFTERNOON. IN ADDITION TO THIS STRONG LOW LEVEL PRESSURE
GRADIENT...RUC UPPER AIR ANALYSIS INDICATES AN 850MB JET STREAK
IN EXCESS OF 60KTS POSITIONED OVER THE WESTERN HALF OF OUR
CWA...WITH SLIGHTLY WEAKER 850MB WINDS NOTED ACROSS OUR EAST. FORECAST
PROXIMITY SOUNDINGS FROM THE RUC...NAM AND OPERATIONAL GFS ALL
SUGGEST AFTERNOON PBL DEPTH WILL LIKELY NEAR 800MB...THUS PROVIDING AN
AFTERNOON GUST POTENTIAL NEAR 55KTS. GIVEN ALL THIS THE CURRENT
POSITION OF THE HIGH WIND WARNING ACROSS OUR WEST AND THE WIND
ADVISORY ACROSS OUR EAST SEEM RIGHT ON AND WILL KEEP THESE
HEADLINES AS IS THROUGH THE REMAINDER OF THE AFTERNOON.
THE AFOREMENTIONED PBL DEPTH AND RESULTANT MIXING WILL ALSO LIKELY
CONTRIBUTE AN ADDITIONAL DECREASE IN AFTERNOON SURFACE DEW
POINTS...BEYOND THE DECREASE WHICH WOULD ALREADY BE OBSERVED WITH
DRY AIR ADVECTION SETTLING IN ACROSS THE AREA. 10-15 DEGREE DROPS
IN DEW POINTS HAVE ALREADY BEEN NOTED THROUGH THE PAST TWO HOURS
AT LOCATIONS SUCH AS KLBF...KBBW AND KTIF...WITH KLXN AND KODX NOT
FAR BEHIND. GIVEN ALL THIS THE CURRENT RFW ACROSS THE WESTERN
TWO-THIRDS OF THE CWA APPEARS TO BE IN GOOD SHAPE AND WILL ALSO
LET THAT RIDE THROUGH THE REMAINDER OF THE AFTERNOON.
&&
.AVIATION...18Z KGRI TAF. VFR CONDITIONS TO CONTINUE AT KGRI
THROUGH THE NEXT 24 HOURS. SURFACE WINDS WILL REMAIN VERY STRONG
FROM THE NORTH/NORTHWEST THIS AFTERNOON AT NEAR 30KTS...GUSTING TO NEAR
45KTS AT TIMES. THE LOW LEVEL PRESSURE GRADIENT IS EXPECTED TO
DIMINISH TOWARDS 00Z PER SHORT TERM GUIDANCE...AND THE GUST
POTENTIAL SHOULD ALSO GREATLY DIMINISH AS THE PBL DECOUPLES FROM
THE STRONGER WINDS ALOFT TOWARDS SUNSET. VISIBILITY RESTRICTIONS ARE
NOT EXPECTED THROUGH THE NEXT 24 HOURS.
&&
.PREV DISCUSSION... /ISSUED 307 AM CST SAT NOV 26 2011/
SHORT TERM...TODAY THROUGH MONDAY NIGHT. THE MAIN CONCERN IN THE
SHORT TERM FORECAST PERIOD WILL BE WINDS TODAY ALONG WITH THE
POSSIBILITY OF RED FLAG CONDITIONS. THE RED FLAG CONCERNS WILL BE
ADDRESSED IN THE FIRE WEATHER PORTION OF THE DISCUSSION LOCATED
BELOW.
A LARGE MID LEVEL TROUGH MOVING ACROSS THE CENTRAL UNITED STATES
THIS MORNING IS PUSHING A STRONG COLD FRONT ACROSS THE REGION.
MSAS 3 HOUR PRESSURE CHANGE ANALYSIS SHOWS PRESSURE RISES NEAR 7
MILLIBARS BEHIND THE FRONT WHICH IS HELPING BRING A NICE SURGE OF
WINDS AS THE BOUNDARY PASSES. WINDS WILL LIKELY SETTLE DOWN TO
SOME DEGREE THIS MORNING BEHIND THE FRONT...HOWEVER IT WILL NOT
TAKE LONG FOR THE WINDS TO INCREASE AGAIN AS MIXING COMMENCES THIS
MORNING. ALL SIGNS STILL POINT TO A DECENT WIND EVENT FOR TODAY
WITH A STRONG SURFACE PRESSURE GRADIENT DEVELOPING DUE TO LOW
PRESSURE TO THE EAST...AND HIGH PRESSURE TO THE WEST.
THE PRIMARY CONCERN SURROUNDS THE GOING HIGH WIND WARNING AND
WIND ADVISORY...AND POTENTIAL CHANGES/ADJUSTMENTS TO THE HEADLINES
FOR TODAY. NAM PROXIMITY SOUNDINGS SUGGEST MIXING TO NEAR H8 IS
LIKELY ACROSS A MAJORITY OF THE FORECAST AREA TODAY...WITH 50 TO
60 KTS OF WIND EXPECTED AT THAT LEVEL. THE FLOW WILL BE FAIRLY
UNIDIRECTIONAL IN THE MIXED LAYER...SO SOME OF THE THE STRONG
WINDS COULD POTENTIALLY TRANSFER TO THE SURFACE. THE HEART OF THE
STRONGER WINDS ARE SHOWN TO RESIDE ACROSS WESTERN PORTIONS OF THE
FORECAST AREA...AND THE CURRENT HIGH WIND WARNING COVERS THAT
WELL. WILL GO AHEAD AND LEAVE THE HEADLINES IN THEIR PRESENT
CONFIGURATION...THOUGH THE NEXT SHIFT WILL OBVIOUSLY HAVE TO WATCH
TRENDS AS THE STRONGER H8 WINDS SHIFT SOUTHEAST THIS AFTERNOON.
A SMALLER CONCERN FOR TODAY WILL BE THE POSSIBILITY OF ANY
LINGERING FLURRIES OR SPRINKLES AS THE LEFT EXIT REGION OF A
100KT UPPER JET SEGMENT SHIFTS THROUGH THE AREA. THE LATEST SREF
AND NCEP 4KM WRF KEEP IT DRY AFTER 12Z TODAY...WHILE THE GFS AND
NOW 26.06Z NAM SUGGESTS THERE COULD BE LINGERING LIGHT
PRECIPITATION IN PARTS OF NORTH CENTRAL KANSAS THIS
MORNING...WHILE THE RUC DEVELOPS LIGHT QPF IN EASTERN PARTS OF THE
FORECAST AREA. CROSS SECTIONS OF RELATIVE HUMIDITY/OMEGA FROM THE
NAM REVEAL DRY LOW LEVELS WHICH WILL BE TOUGH TO
OVERCOME...ESPECIALLY AS THE FORCING WEAKENS...SO WOULD RATHER
CARRY A NON MEASURABLE EVENT SUCH AS SPRINKLES OR FLURRIES. H85
TEMPERATURES QUICKLY FALL BELOW FREEZING THIS MORNING...HOWEVER
ABOVE FREEZING H925 TEMPERATURES WILL PERSIST...SO WILL GO WITH
SPRINKLES/FLURRIES IN THE GRIDS.
THE STRONGEST OF THE WINDS SHOULD SUBSIDE BY EARLY EVENING AS
MIXING BEGINS TO DIMINISH. H5 HEIGHTS BEGIN TO RISE
TONIGHT...WITH WARMER AIR GRADUALLY RETURNING FOR SUNDAY AND
MONDAY. IN FACT...H85 TEMPERATURES RISE FROM -5 DEGREES CELSIUS
TONIGHT...TO NEARLY +10 DEGREES CELSIUS ON MONDAY IN PORTIONS OF
THE FORECAST AREA. WILL AIM FOR HIGHS IN THE MID 40S TO LOWER 50S
ON SUNDAY...WITH 50S ON MONDAY.
ANOTHER MID LEVEL WAVE HELPS KNOCK DOWN THE RIDGE MONDAY AFTERNOON
INTO MONDAY NIGHT...WITH ANOTHER COLD FRONT PLOWING THROUGH THE
AREA. MOISTURE APPEARS LIMITED WITH THE PASSAGE OF THE WAVE/FRONT
AND WILL MAINTAIN A DRY FORECAST AS IT PASSES. WINDS WILL AGAIN
BECOME GUSTY AS THE FRONT PASSES...BUT CURRENTLY IT APPEARS SPEEDS
SHOULD STAY BELOW ADVISORY LEVELS.
LONG TERM...TUESDAY THROUGH FRIDAY.
MODELS NOT IN TOO BAD OF AGREEMENT AT THE START OF THE LONG TERM
PERIOD...WITH NORTHWESTERLY FLOW SET UP IN THE UPPER LEVELS AS A
LOW PRESSURE SYSTEM SPINS OVER THE SOUTHEASTERN CONUS AND A
RIDGE AXIS SETS UP OVER THE WEST COAST. WITH NO DISTURBANCES
EXPECTED TO PUSH THROUGH THE REGION...FORECAST FOR TUESDAY REMAINS
DRY. GETTING INTO TUESDAY NIGHT THROUGH THURSDAY...EXPECTING TO
SEE SHORTWAVE UPPER LEVEL RIDGING BUILD INTO THE CENTRAL PLAINS
EXTENDING FROM THE AREA OF HIGH PRESSURE CENTERED JUST OFF THE SRN
COAST OF CA...BETWEEN THE LOW PRESSURE CONTINUES TO PUSH NORTHEAST
TOWARD THE EAST COAST AND ANOTHER DISTURBANCE MOVING FROM THE PAC
NW INTO THE ROCKIES.
A LITTLE MORE UNCERTAINTY ARISES INTO THURSDAY AND FRIDAY WITH THE
LATEST MODEL RUNS HAVING A FEW DIFFERENCES. THE GENERAL STORY IS
THE DISTURBANCE WHICH HAS SHIFTED INTO THE ROCKIES BECOMES
SPLIT...WITH A CLOSED LOW DEVELOPING OVER THE WRN/SWRN CONUS...BUT
MODELS VARY ON THE TIMING AND LOCATION OF THE LOW AND WHAT HAPPENS
WITH THE NORTHERN ENERGY. THE GFS PUSHES THE NORTHERN ENERGY
FURTHER SOUTH INTO THE REGION...WHILE THE ECMWF SHOWS MORE RIDGING
HELPING TO PUSH IT FURTHER EAST. INTRODUCED SMALL PRECIPITATION
CHANCES ACROSS THE NORTHERN PORTIONS OF THE CWA TO ACCOUNT FOR
THIS DISTURBANCE IN THE REGION...BUT KEPT IT CONFINED TO THE
DAYTIME HOURS ON THURSDAY. TEMPERATURES SUGGEST THE PTYPE WOULD BE
SNOW. ANY PRECIPITATION WOULD NOT STICK AROUND LONG...AND KEPT
THURSDAY NIGHT AND FRIDAY DRY.
WHILE A BUMP UP IN TEMPERATURES IS EXPECTED ON WEDNESDAY WITH THE
RIDGING SET UP AND HIGHS IN THE UPPER 40S TO LOWER/MID
50S...COMPARED TO THE LOWER/MID 40S ON TUESDAY...A COLD FRONT IS
EXPECTED TO PUSH THROUGH THE CWA EARLY THURSDAY. THE COOLER AIR
ACCOMPANYING THE FRONT LOOKS TO DROP HIGHS FOR THURSDAY INTO THE
MID 30S TO LOWER 40S...WITH MID 30S EXPECTED FOR FRIDAY.
FIRE WEATHER...AS STATED ABOVE WINDS TODAY WILL EASILY EXCEED
THE 25 KT GUST CRITERIA NEEDED FOR A RED FLAG WARNING. THE BIGGEST
CONCERN WILL BE RELATIVE HUMIDITY VALUES DROPPING TO 20 PERCENT
OR LESS. THE NAM AND GFS HAVE BOTH COME IN WITH HIGHER SURFACE
DEWPOINTS ON THE 00Z RUNS...AND THIS TREND IS ALSO EVIDENT EVEN
WHEN MIXING DEWPOINTS ALOFT TO THE SURFACE. THAT BEING SAID...AM
STILL CONCERNED ABOUT FIRE WEATHER ISSUES TODAY...ESPECIALLY WITH
THE LATEST ECMWF STILL SUPPORTING LOWER DEWPOINTS THIS AFTERNOON.
WILL HOLD ONTO THE LOWER DEWPOINTS SHOWN BY THE CURRENT FORECAST
AND LATEST ECMWF AND KEEP THE RED FLAG WARNING IN PLACE FOR THIS
AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ041-048-049-063-
064-076-077-086-087.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ039-040-046-
047-060>062-072>075-082>085.
RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ039-040-046-
047-060>062-072>075-082>085.
KS...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR KSZ007-019.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR KSZ005-006-017-
018.
RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR KSZ005>007-
017>019.
&&
$$
UPDATE/AVIATION...BRYANT
SHORT TERM/FIRE WEATHER...KING
LONG TERM...ADO
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1143 AM CST SAT NOV 26 2011
.AVIATION...
18Z TAFS FOR KOFK...KOMA...KLNK.
STRONG NORTHWEST WINDS WITH GUSTS TO 45 KTS AT TIMES THROUGH
00Z. VFR CONDITIONS DEVELOPING WITH BKN LAYER MOVING EAST
00Z-06Z.
&&
.PREV DISCUSSION... /ISSUED 523 AM CST SAT NOV 26 2011/
AVIATION...12Z TAFS FOR KOFK...KOMA...KLNK.
MAIN CONCERN WILL BE VERY GUSTY NORTHWEST SFC WINDS THRU THE DAY.
GUSTS ARE EXPECTED TO INCREASE TO NEAR 40 KTS BY LATE MORNING AND
EARLY AFTERNOON. MVFR CONDITIONS ARE EXPECTED THIS MORNING FOR
KOFK AND KOMA HOWEVER SHOULD IMPROVE TO VFR BY EARLY AFTERNOON.
WINDS WILL BEGIN TO DIMINISH LATER THIS EVENING.
PREV DISCUSSION... /ISSUED 325 AM CST SAT NOV 26 2011/
DISCUSSION...
MAIN FORECAST CONCERN IS WIND TODAY. WATER VAPOR IMAGERY EARLY THIS
MORNING SHOWED A FAIRLY IMPRESSIVE TROUGH EXTENDING FROM SASKATCHEWAN
DOWN INTO MEXICO. 500 MB HEIGHT FALLS WERE AROUND OR IN EXCESS OF
100 METERS FROM SOUTHWEST NEBRASKA TO WEST TEXAS LAST EVENING. A FEW
THUNDERSTORMS WERE NOTED NEAR THE KANSAS/OKLAHOMA BORDER. A COLD
FRONT STRETCHED FROM LOW PRESSURE OVER SOUTHERN MINNESOTA DOWN INTO
WESTERN OKLAHOMA.
THE TROUGH AND FRONT WILL BOTH CONTINUE TO MOVE EAST TODAY...WITH A
TIGHT PRESSURE GRADIENT AND STRONG WINDS SPREADING EAST ACROSS THE
AREA. DELAYED WIND ADVISORY A FEW HOURS FOR PARTS OF THE AREA THIS
MORNING...BUT OTHERWISE WIND FORECAST IS SIMILAR TO PREVIOUS GRIDS.
THE 06Z RUC MODEL DID SHOW SOME LIGHT PRECIPITATION MOVING INTO PARTS
OF NORTHEAST NEBRASKA THROUGH 18Z. OTHERWISE...THE SHOWERS IN FAR
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SHOULD MOVE OUT VERY EARLY
THIS MORNING. MUCH COLDER AIR WILL MOVE INTO THE AREA TODAY. LOWS
TONIGHT SHOULD BOTTOM OUT IN THE UPPER TEENS TO MID 20S. WINDS WILL
REMAIN BRISK AT LEAST EARLY TONIGHT BUT MOST LIKELY BELOW ADVISORY
LEVELS. AS HIGH PRESSURE AT THE SURFACE BUILDS INTO THE AREA ON
SUNDAY...WINDS WILL DECREASE. EXPECT WEAK RETURN FLOW TO SETUP LATE
SUNDAY NIGHT...BUT IS NOT EXPECTED TO BE STRONG ENOUGH TO KEEP LOWS
UP MUCH ABOVE MOS GUIDANCE.
MILDER AIR SHOULD BE OVER THE AREA MONDAY...WITH HIGHS IN THE UPPER
40S AND LOWER 50S. NEXT COLD FRONT PUSHES THROUGH MONDAY NIGHT...BUT
SHOULD NOT PRODUCE ANY PRECIPITATION. KEPT TUESDAY AND WEDNESDAY DRY
BUT ADDED A SLIGHT CHANCE OF LIGHT SNOW FOR ABOUT THE NORTHERN HALF
OF THE FORECAST AREA THURSDAY. 00Z GFS WAS THE BEST MODEL DEPICTING
THAT SCENARIO.
MILLER
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ011-012-015>018-
030>034-042>045-050>053-065>068-078-088>093.
IA...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ043-055-056-069-
079-080-090-091.
&&
$$
FOBERT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1142 AM CST SAT NOV 26 2011
.AVIATION...
WINDS CONTINUE TO BE THE MAIN IMPACT OF THE AVIATION FORECAST
THROUGH SUNDAY MORNING. THE PRESSURE GRADIENT WILL SLACKEN THROUGH
THE REMAINDER OF THE DAY TODAY AND WITH SUNDOWN EXPECT DECOUPLING
OF THE BOUNDARY LAYER SO SHOULD SEE WINDS DECREASE APPRECIABLY
THIS EVENING. ONE THING TO LOOK FOR THIS EVENING IS THE
POSSIBILITY FOR LOW LEVEL WIND SHEAR AS THE BOUNDARY LAYER
DECOUPLES BEFORE THE WINDS AT OR ABOVE 1K FEET DECREASE. BUFKIT
SOUNDINGS SHOWING 35 TO 45 KT WINDS AT AROUND 1900FT EARLY THIS
EVENING BUT INSERTING LLWS IN THE TAF WILL DEPEND IF THE SURFACE
WINDS HAVE DECREASED BY THEN. WITH LOWER CONFIDENCE... DID NOT ADD
THEM IN THE FORECAST. WILL WATCH TRENDS THROUGH THE AFTERNOON AND
WILL ADD IN IF IT WARRANTS IT.
THROUGH THE REMAINDER OF THE AFTERNOON...LOOKING FOR NORTHWEST
WINDS OF 30 TO 40KTS WITH GUSTS UP TO 55KTS. THEN BY MID
EVENING...THE WINDS SHOULD DROP DOWN BELOW 12KTS FOR ALL AREAS.
HIGH PRESSURE BUILDING INTO THE PLAINS OVERNIGHT WILL KEEP WINDS
RATHER LIGHT THROUGH THE DAY ON SUNDAY AS AFTERNOON MIXING WILL
ONLY LEAD TO WINDS UP TO 12KTS. DRY AIR WILL BE IN PLACE AS WELL
SO EXPECTING CLEAR SKIES THROUGH SUNDAY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 312 AM CST SAT NOV 26 2011/
DISCUSSION...
SHORT TERM...
BUFKIT IS ON TRIAL TODAY AS IT CONTINUES TO ADVERTISE VERY STRONG
WINDS...40 TO 45 KTS AT 1000 TO 1500 FT AGL. THIS SHOULD TRANSLATE
TO SFC WINDS OF 40 MPH OR STRONGER AND ALL MODELS IN BUFKIT SHOW
THIS.
THE MODEL GUIDANCE AND DIRECT OUTPUT HAVE BEEN WOBBLING SHOWING
WIND SPEEDS RUNNING ABOVE AND BELOW HIGH WIND CRITERIA. BUFKIT HAS
BEEN VERY RELIABLE THOUGH SUGGESTING HIGH WINDS WILL DEVELOP.
THE LATEST MAV MET GUIDANCE WIND SPEEDS HAVE SLOWED
SOME...SUGGESTING A HIGH END WIND ADVISORY ACROSS MOST AREAS. THE
EXCEPTION AT KBBW. THE 06Z NAM HOWEVER INDICATES 65 KT WINDS AT
800MB...THE APPROXIMATE MIXING DEPTH EXPECTED ACROSS NCNTL NEB
THIS AFTN. A CORRIDOR OF HIGH WINDS IS EXPECTED TO DEVELOP FROM
KVTN SSE THROUGH KBBW TODAY. DEEPER VERTICAL MIXING IS EXPECTED TO
PRODUCE HIGH WIND GUSTS ACROSS SWRN NEB THIS AFTERNOON ALSO. A
BLEND OF HRRR AND NAMDNG WIND GUST DATA PRODUCED GUSTS TO 55 MPH.
A FEW KNOTS WERE ADDED TO THE FCST TO BRING GUSTS SPEEDS TO 60 MPH
WHICH IS CERTAINLY REACHABLE GIVEN THE 65 KT WINDS AT 800MB SHOWN
IN THE NAM. ALSO KTIF AND KLBF GUSTED TO 47 MPH BETWEEN 8 AND 9Z
BUT HRRR SUGGESTED GUSTS TO 58 MPH WOULD DEVELOP. THE 06Z NAM
FRH68 DATA SUGGESTED 35 KTS IN LOWEST 35 MB THIS AFTERNOON AT
KLBF...ROUGHLY 35 MPH AT THE SFC. 35 MPH IN THE VALLEY SHOULD
EQUATE TO 40 MPH IN THE SANDHILLS NORTH AND SOUTH OF TOWN.
THE HIGH WIND WARNING APPEARS TO BE ON TRACK ACROSS A GOOD
PORTION OF THE FORECAST AREA. WEAKNESSES IN THE WIND FIELDS WERE
NOTED AT BOYD AND WHEELER COUNTIES AND ACROSS SHERIDAN COUNTY.
WIND SPEEDS SHOULD DROP OFF RAPIDLY BETWEEN 4 AND 6 PM CST AS
VERY DRY AIR WILL MOVE IN THIS AFTN. BY SUNDAY MORNING 1035MB HIGH
PRESSURE SHOULD BE ACROSS THE FCST AREA AND WINDS IN THE VALLEYS
SHOULD FALL OFF TO LESS THAN 10 MPH. LOWS IN THE TEENS SHOULD BE
COMMON.
LONG TERM...
ANOTHER STRONG PACIFIC COLD FRONT WILL MOVE THROUGH THE FCST AREA
MONDAY WITH WINDS INCREASING...PERHAPS TO WIND ADVISORY
CRITERIA...30 MPH. MIX DOWN WIND TOOLS PRODUCED WINDS NEAR 30 MPH
AND GFS AND ECMWF SHOW SOME 50 KT WINDS AT 850MB MONDAY AFTERNOON.
FOR NOW A LIMITER WAS USED FOR 20 TO 30 MPH WIND SPEEDS AND LATER
FCSTS CAN ADJUST UP IF NECESSARY. BY TUESDAY MORNING 1035 MPH HIGH
PRESSURE IS CENTERED SOMEWHERE BETWEEN SD AND NERN COLO WITH LOWS
IN THE TEENS. THIS HIGH WILL THEN MOVE OFF TO THE SOUTHEAST TO BE
FOLLOWED BY A STRONGER MORE ARCTIC TYPE HIGH PRESSURE SYSTEM
WEDNESDAY NIGHT AND THURSDAY. THE FRONT APPEARS TO BE CARRYING
SOME MOISTURE WITH IT FROM THE HIGH LATITUDES. SO WE CONTINUE THE
FORECAST FOR SCATTERED SNOW SHOWERS. TEMPS AHEAD OF THE FRONT
APPEAR TO BE COLD ENOUGH FOR SNOW VS FREEZING DRIZZLE CHANGING TO
SNOW. EITHER WAY VERY LIGHT PCPN AMOUNTS ARE EXPECTED WITH THE
FRONT AND MAINLY ACROSS THE NORTHWEST ZONES.
MAX TEMPS TODAY THROUGH WEDNESDAY WILL BE MOSTLY IN THE 40S TO
LOWER 50S. BEHIND THE ARCTIC FRONT THURSDAY AND FRIDAY HIGHS
REACH ONLY INTO THE 30S.
SO THE GEM...GFS...ECMWF AND GEF ARE IN VERY GOOD AGREEMENT
THROUGH WEDNESDAY. THEREAFTER...TIMING PROBLEMS DEVELOP WITH THE
ARCTIC FRONT WHICH APPEAR TO BE RELATED TO DISTURBANCES UPSTREAM
AND DOWNSTREAM ACROSS THE WRN AND ERN U.S. THE GFS APPEARED TO BE
THE MOST RATIONAL SOLN. TIMING-WISE IT WAS SLOWER THAN THE GEM
AND FASTER THAN THE ECMWF.
FIRE WEATHER... VERY GUSTY NORTHWEST WINDS WILL CONTINUE THROUGH
THE DAY. DRY AIR IS EXPECTED TO ADVECT INTO THE REGION...DROPPING
DEW POINT TEMPS INTO THE TEENS AND SINGLE DIGITS. THIS WILL
COMBINE WITH HIGHS IN THE 40S TO PRODUCE MINIMUM RELATIVE HUMIDITY
VALUES AROUND 20 PERCENT...LOWEST IN SW NEB. WILL CONTINUE THE RED
FLAG WARNING FOR ALL BUT ZONE 208...WHERE RH VALUES CLOSER TO 30
PERCENT ARE EXPECTED. ALTHOUGH THE AREA MAY NOT REACH THE TYPICAL
WIDESPREAD RH MINIMUM PERCENTAGES OF 15 PERCENT NEEDED FOR A RED
FLAG...THE COMBINATION OF WIND GUSTS ABOVE 50 MPH...THE VERY DRY
FUELS AND STILL LOW RH VALUES AROUND 20 PERCENT WARRANT THE
HEADLINE. THERE IS A SMALL CHANCE THE DRIER AIR IS DELAYED...WHICH
WOULD RESULT IN WIDESPREAD MINIMUM RH PERCENTAGES IN THE 30S. LOW
CONFIDENCE ON THIS SCENARIO AND WANT TO ERROR ON THE SIDE OF
CAUTION.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...HIGH WIND WARNING UNTIL 6 PM
CST /5 PM MST/ THIS EVENING FOR
NEZ004>010-022>029-035>038-056>059-069>071-094.
RED FLAG WARNING UNTIL 6 PM CST /5 PM MST/ THIS EVENING FOR
NEZ204-206-209-210-219.
&&
$$
SHORT TERM/EXTENDED...CDC
AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
548 AM CST SAT NOV 26 2011
.AVIATION...12Z TAF. NO SIGNIFICANT CHANGES FOR THIS TAF
PERIOD...WITH THE MAIN CONCERN CONTINUING TO LIE WITH WINDS. THE
SURFACE COLD FRONT HAS CLEARED THE TERMINAL AREA...AND
NORTHWESTERLY WINDS HAVE BUILT IN BEHIND...WHICH WILL STICK AROUND
FOR THE ENTIRE TAF PERIOD. SPEEDS ARE ALREADY SUSTAINED NEAR 25 TO
30 MPH WITH GUSTS NEAR 45 MPH...AND INCREASED SPEEDS OF 30 TO 40
MPH WITH HIGHER GUSTS WILL BE POSSIBLE. THIS EVENING WINDS WILL
BEGIN TO TAPER OFF. VFR CONDITIONS WILL REMAIN AS CURRENT CLOUD
COVER SITS IN THE MID/UPPER LEVELS...AND BY MIDDAY SKIES ARE
EXPECTED TO CLEAR.
&&
.PREV DISCUSSION... /ISSUED 307 AM CST SAT NOV 26 2011/
SHORT TERM...TODAY THROUGH MONDAY NIGHT. THE MAIN CONCERN IN THE
SHORT TERM FORECAST PERIOD WILL BE WINDS TODAY ALONG WITH THE
POSSIBILITY OF RED FLAG CONDITIONS. THE RED FLAG CONCERNS WILL BE
ADDRESSED IN THE FIRE WEATHER PORTION OF THE DISCUSSION LOCATED
BELOW.
A LARGE MID LEVEL TROUGH MOVING ACROSS THE CENTRAL UNITED STATES
THIS MORNING IS PUSHING A STRONG COLD FRONT ACROSS THE REGION.
MSAS 3 HOUR PRESSURE CHANGE ANALYSIS SHOWS PRESSURE RISES NEAR 7
MILLIBARS BEHIND THE FRONT WHICH IS HELPING BRING A NICE SURGE OF
WINDS AS THE BOUNDARY PASSES. WINDS WILL LIKELY SETTLE DOWN TO
SOME DEGREE THIS MORNING BEHIND THE FRONT...HOWEVER IT WILL NOT
TAKE LONG FOR THE WINDS TO INCREASE AGAIN AS MIXING COMMENCES THIS
MORNING. ALL SIGNS STILL POINT TO A DECENT WIND EVENT FOR TODAY
WITH A STRONG SURFACE PRESSURE GRADIENT DEVELOPING DUE TO LOW
PRESSURE TO THE EAST...AND HIGH PRESSURE TO THE WEST.
THE PRIMARY CONCERN SURROUNDS THE GOING HIGH WIND WARNING AND
WIND ADVISORY...AND POTENTIAL CHANGES/ADJUSTMENTS TO THE HEADLINES
FOR TODAY. NAM PROXIMITY SOUNDINGS SUGGEST MIXING TO NEAR H8 IS
LIKELY ACROSS A MAJORITY OF THE FORECAST AREA TODAY...WITH 50 TO
60 KTS OF WIND EXPECTED AT THAT LEVEL. THE FLOW WILL BE FAIRLY
UNIDIRECTIONAL IN THE MIXED LAYER...SO SOME OF THE THE STRONG
WINDS COULD POTENTIALLY TRANSFER TO THE SURFACE. THE HEART OF THE
STRONGER WINDS ARE SHOWN TO RESIDE ACROSS WESTERN PORTIONS OF THE
FORECAST AREA...AND THE CURRENT HIGH WIND WARNING COVERS THAT
WELL. WILL GO AHEAD AND LEAVE THE HEADLINES IN THEIR PRESENT
CONFIGURATION...THOUGH THE NEXT SHIFT WILL OBVIOUSLY HAVE TO WATCH
TRENDS AS THE STRONGER H8 WINDS SHIFT SOUTHEAST THIS AFTERNOON.
A SMALLER CONCERN FOR TODAY WILL BE THE POSSIBILITY OF ANY
LINGERING FLURRIES OR SPRINKLES AS THE LEFT EXIT REGION OF A
100KT UPPER JET SEGMENT SHIFTS THROUGH THE AREA. THE LATEST SREF
AND NCEP 4KM WRF KEEP IT DRY AFTER 12Z TODAY...WHILE THE GFS AND
NOW 26.06Z NAM SUGGESTS THERE COULD BE LINGERING LIGHT
PRECIPITATION IN PARTS OF NORTH CENTRAL KANSAS THIS
MORNING...WHILE THE RUC DEVELOPS LIGHT QPF IN EASTERN PARTS OF THE
FORECAST AREA. CROSS SECTIONS OF RELATIVE HUMIDITY/OMEGA FROM THE
NAM REVEAL DRY LOW LEVELS WHICH WILL BE TOUGH TO
OVERCOME...ESPECIALLY AS THE FORCING WEAKENS...SO WOULD RATHER
CARRY A NON MEASURABLE EVENT SUCH AS SPRINKLES OR FLURRIES. H85
TEMPERATURES QUICKLY FALL BELOW FREEZING THIS MORNING...HOWEVER
ABOVE FREEZING H925 TEMPERATURES WILL PERSIST...SO WILL GO WITH
SPRINKLES/FLURRIES IN THE GRIDS.
THE STRONGEST OF THE WINDS SHOULD SUBSIDE BY EARLY EVENING AS
MIXING BEGINS TO DIMINISH. H5 HEIGHTS BEGIN TO RISE
TONIGHT...WITH WARMER AIR GRADUALLY RETURNING FOR SUNDAY AND
MONDAY. IN FACT...H85 TEMPERATURES RISE FROM -5 DEGREES CELSIUS
TONIGHT...TO NEARLY +10 DEGREES CELSIUS ON MONDAY IN PORTIONS OF
THE FORECAST AREA. WILL AIM FOR HIGHS IN THE MID 40S TO LOWER 50S
ON SUNDAY...WITH 50S ON MONDAY.
ANOTHER MID LEVEL WAVE HELPS KNOCK DOWN THE RIDGE MONDAY AFTERNOON
INTO MONDAY NIGHT...WITH ANOTHER COLD FRONT PLOWING THROUGH THE
AREA. MOISTURE APPEARS LIMITED WITH THE PASSAGE OF THE WAVE/FRONT
AND WILL MAINTAIN A DRY FORECAST AS IT PASSES. WINDS WILL AGAIN
BECOME GUSTY AS THE FRONT PASSES...BUT CURRENTLY IT APPEARS SPEEDS
SHOULD STAY BELOW ADVISORY LEVELS.
LONG TERM...TUESDAY THROUGH FRIDAY.
MODELS NOT IN TOO BAD OF AGREEMENT AT THE START OF THE LONG TERM
PERIOD...WITH NORTHWESTERLY FLOW SET UP IN THE UPPER LEVELS AS A
LOW PRESSURE SYSTEM SPINS OVER THE SOUTHEASTERN CONUS AND A
RIDGE AXIS SETS UP OVER THE WEST COAST. WITH NO DISTURBANCES
EXPECTED TO PUSH THROUGH THE REGION...FORECAST FOR TUESDAY REMAINS
DRY. GETTING INTO TUESDAY NIGHT THROUGH THURSDAY...EXPECTING TO
SEE SHORTWAVE UPPER LEVEL RIDGING BUILD INTO THE CENTRAL PLAINS
EXTENDING FROM THE AREA OF HIGH PRESSURE CENTERED JUST OFF THE SRN
COAST OF CA...BETWEEN THE LOW PRESSURE CONTINUES TO PUSH NORTHEAST
TOWARD THE EAST COAST AND ANOTHER DISTURBANCE MOVING FROM THE PAC
NW INTO THE ROCKIES.
A LITTLE MORE UNCERTAINTY ARISES INTO THURSDAY AND FRIDAY WITH THE
LATEST MODEL RUNS HAVING A FEW DIFFERENCES. THE GENERAL STORY IS
THE DISTURBANCE WHICH HAS SHIFTED INTO THE ROCKIES BECOMES
SPLIT...WITH A CLOSED LOW DEVELOPING OVER THE WRN/SWRN CONUS...BUT
MODELS VARY ON THE TIMING AND LOCATION OF THE LOW AND WHAT HAPPENS
WITH THE NORTHERN ENERGY. THE GFS PUSHES THE NORTHERN ENERGY
FURTHER SOUTH INTO THE REGION...WHILE THE ECMWF SHOWS MORE RIDGING
HELPING TO PUSH IT FURTHER EAST. INTRODUCED SMALL PRECIPITATION
CHANCES ACROSS THE NORTHERN PORTIONS OF THE CWA TO ACCOUNT FOR
THIS DISTURBANCE IN THE REGION...BUT KEPT IT CONFINED TO THE
DAYTIME HOURS ON THURSDAY. TEMPERATURES SUGGEST THE PTYPE WOULD BE
SNOW. ANY PRECIPITATION WOULD NOT STICK AROUND LONG...AND KEPT
THURSDAY NIGHT AND FRIDAY DRY.
WHILE A BUMP UP IN TEMPERATURES IS EXPECTED ON WEDNESDAY WITH THE
RIDGING SET UP AND HIGHS IN THE UPPER 40S TO LOWER/MID
50S...COMPARED TO THE LOWER/MID 40S ON TUESDAY...A COLD FRONT IS
EXPECTED TO PUSH THROUGH THE CWA EARLY THURSDAY. THE COOLER AIR
ACCOMPANYING THE FRONT LOOKS TO DROP HIGHS FOR THURSDAY INTO THE
MID 30S TO LOWER 40S...WITH MID 30S EXPECTED FOR FRIDAY.
FIRE WEATHER...AS STATED ABOVE WINDS TODAY WILL EASILY EXCEED
THE 25 KT GUST CRITERIA NEEDED FOR A RED FLAG WARNING. THE BIGGEST
CONCERN WILL BE RELATIVE HUMIDITY VALUES DROPPING TO 20 PERCENT
OR LESS. THE NAM AND GFS HAVE BOTH COME IN WITH HIGHER SURFACE
DEWPOINTS ON THE 00Z RUNS...AND THIS TREND IS ALSO EVIDENT EVEN
WHEN MIXING DEWPOINTS ALOFT TO THE SURFACE. THAT BEING SAID...AM
STILL CONCERNED ABOUT FIRE WEATHER ISSUES TODAY...ESPECIALLY WITH
THE LATEST ECMWF STILL SUPPORTING LOWER DEWPOINTS THIS AFTERNOON.
WILL HOLD ONTO THE LOWER DEWPOINTS SHOWN BY THE CURRENT FORECAST
AND LATEST ECMWF AND KEEP THE RED FLAG WARNING IN PLACE FOR THIS
AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ041-048-049-063-
064-076-077-086-087.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ039-040-046-
047-060>062-072>075-082>085.
RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR
NEZ039-040-046-047-060>062-072>075-082>085.
KS...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR KSZ007-019.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR KSZ005-006-017-
018.
RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR
KSZ005>007-017>019.
&&
$$
SHORT/FIRE...KING
LONG/AVIATION...ADO
AREA FORECAST DISCUSSION...CORRECTED
NWS NORTH PLATTE NE
537 AM CST SAT NOV 26 2011
.AVIATION...
EXPECT VFR CONDITIONS AND VERY GUSTY NORTHWEST WINDS TODAY. COLD
FRONT HAS PUSHED WELL TO THE EAST WITH HIGH PRESSURE BUILDING
OVER THE ROCKIES WHICH IS RESULTING IN WIDESPREAD NORTHWEST WINDS
ON THE INCREASE. LOCALLY GUSTS ABOVE 40 KTS WILL CONTINUE INTO
THE MID MORNING HOURS...THEN WIDESPREAD GUSTS ABOVE 40 KTS AND
APPROACHING 50 KTS ARE EXPECTED. SUNSET WILL ALLOW FOR WINDS TO
DIMINISH QUICKLY AS THE BOUNDARY LAYER DECOUPLES. BKN/OVC CIGS
AROUND 10K FT AGL WILL PUSH EAST BY MID MORNING OR EARLY
AFTERNOON. ONCE SKIES CLEAR...EXPECT THEM TO REMAIN CLR INTO
SATURDAY NIGHT.
&&
.PREV DISCUSSION... /ISSUED 312 AM CST SAT NOV 26 2011/
DISCUSSION...
SHORT TERM...
BUFKIT IS ON TRIAL TODAY AS IT CONTINUES TO ADVERTISE VERY STRONG
WINDS...40 TO 45 KTS AT 1000 TO 1500 FT AGL. THIS SHOULD TRANSLATE
TO SFC WINDS OF 40 MPH OR STRONGER AND ALL MODELS IN BUFKIT SHOW
THIS.
THE MODEL GUIDANCE AND DIRECT OUTPUT HAVE BEEN WOBBLING SHOWING
WIND SPEEDS RUNNING ABOVE AND BELOW HIGH WIND CRITERIA. BUFKIT HAS
BEEN VERY RELIABLE THOUGH SUGGESTING HIGH WINDS WILL DEVELOP.
THE LATEST MAV MET GUIDANCE WIND SPEEDS HAVE SLOWED
SOME...SUGGESTING A HIGH END WIND ADVISORY ACROSS MOST AREAS. THE
EXCEPTION AT KBBW. THE 06Z NAM HOWEVER INDICATES 65 KT WINDS AT
800MB...THE APPROXIMATE MIXING DEPTH EXPECTED ACROSS NCNTL NEB
THIS AFTN. A CORRIDOR OF HIGH WINDS IS EXPECTED TO DEVELOP FROM
KVTN SSE THROUGH KBBW TODAY. DEEPER VERTICAL MIXING IS EXPECTED TO
PRODUCE HIGH WIND GUSTS ACROSS SWRN NEB THIS AFTERNOON ALSO. A
BLEND OF HRRR AND NAMDNG WIND GUST DATA PRODUCED GUSTS TO 55 MPH.
A FEW KNOTS WERE ADDED TO THE FCST TO BRING GUSTS SPEEDS TO 60 MPH
WHICH IS CERTAINLY REACHABLE GIVEN THE 65 KT WINDS AT 800MB SHOWN
IN THE NAM. ALSO KTIF AND KLBF GUSTED TO 47 MPH BETWEEN 8 AND 9Z
BUT HRRR SUGGESTED GUSTS TO 58 MPH WOULD DEVELOP. THE 06Z NAM
FRH68 DATA SUGGESTED 35 KTS IN LOWEST 35 MB THIS AFTERNOON AT
KLBF...ROUGHLY 35 MPH AT THE SFC. 35 MPH IN THE VALLEY SHOULD
EQUATE TO 40 MPH IN THE SANDHILLS NORTH AND SOUTH OF TOWN.
THE HIGH WIND WARNING APPEARS TO BE ON TRACK ACROSS A GOOD
PORTION OF THE FORECAST AREA. WEAKNESSES IN THE WIND FIELDS WERE
NOTED AT BOYD AND WHEELER COUNTIES AND ACROSS SHERIDAN COUNTY.
WIND SPEEDS SHOULD DROP OFF RAPIDLY BETWEEN 4 AND 6 PM CST AS
VERY DRY AIR WILL MOVE IN THIS AFTN. BY SUNDAY MORNING 1035MB HIGH
PRESSURE SHOULD BE ACROSS THE FCST AREA AND WINDS IN THE VALLEYS
SHOULD FALL OFF TO LESS THAN 10 MPH. LOWS IN THE TEENS SHOULD BE
COMMON.
LONG TERM...
ANOTHER STRONG PACIFIC COLD FRONT WILL MOVE THROUGH THE FCST AREA
MONDAY WITH WINDS INCREASING...PERHAPS TO WIND ADVISORY
CRITERIA...30 MPH. MIX DOWN WIND TOOLS PRODUCED WINDS NEAR 30 MPH
AND GFS AND ECMWF SHOW SOME 50 KT WINDS AT 850MB MONDAY AFTERNOON.
FOR NOW A LIMITER WAS USED FOR 20 TO 30 MPH WIND SPEEDS AND LATER
FCSTS CAN ADJUST UP IF NECESSARY. BY TUESDAY MORNING 1035 MPH HIGH
PRESSURE IS CENTERED SOMEWHERE BETWEEN SD AND NERN COLO WITH LOWS
IN THE TEENS. THIS HIGH WILL THEN MOVE OFF TO THE SOUTHEAST TO BE
FOLLOWED BY A STRONGER MORE ARCTIC TYPE HIGH PRESSURE SYSTEM
WEDNESDAY NIGHT AND THURSDAY. THE FRONT APPEARS TO BE CARRYING
SOME MOISTURE WITH IT FROM THE HIGH LATITUDES. SO WE CONTINUE THE
FORECAST FOR SCATTERED SNOW SHOWERS. TEMPS AHEAD OF THE FRONT
APPEAR TO BE COLD ENOUGH FOR SNOW VS FREEZING DRIZZLE CHANGING TO
SNOW. EITHER WAY VERY LIGHT PCPN AMOUNTS ARE EXPECTED WITH THE
FRONT AND MAINLY ACROSS THE NORTHWEST ZONES.
MAX TEMPS TODAY THROUGH WEDNESDAY WILL BE MOSTLY IN THE 40S TO
LOWER 50S. BEHIND THE ARCTIC FRONT THURSDAY AND FRIDAY HIGHS
REACH ONLY INTO THE 30S.
SO THE GEM...GFS...ECMWF AND GEF ARE IN VERY GOOD AGREEMENT
THROUGH WEDNESDAY. THEREAFTER...TIMING PROBLEMS DEVELOP WITH THE
ARCTIC FRONT WHICH APPEAR TO BE RELATED TO DISTURBANCES UPSTREAM
AND DOWNSTREAM ACROSS THE WRN AND ERN U.S. THE GFS APPEARED TO BE
THE MOST RATIONAL SOLN. TIMING-WISE IT WAS SLOWER THAN THE GEM
AND FASTER THAN THE ECMWF.
AVIATION...
EXPECT VFR CONDITIONS AND VERY GUSTY NORTHWEST TODAY. COLD FRONT HAS
PUSHED WELL TO THE EAST WITH WIDESPREAD NORTHWEST WINDS ON THE
INCREASE. LOCALLY GUSTS ABOVE 40 KTS WILL CONTINUE INTO THE MID
MORNING HOURS...THEN WIDESPREAD GUSTS ABOVE 40 KTS ARE EXPECTED.
SUNSET WILL ALLOW FOR WINDS TO DIMINISH QUICKLY AS THE BOUNDARY
LAYER DECOUPLES. BKN/OVC CIGS AROUND 10K FT AGL WILL PUSH EAST BY
MID MORNING OR EARLY AFTERNOON. THERE IS A POSSIBILITY FOR A SCT/BKN
VFR CU FIELD THIS AFTERNOON...HOWEVER LOW CONFIDENCE IN ITS
DEVELOPMENT AS DRY AIR ADVECTS INTO THE REGION. SKIES SHOULD BE
CLEAR BY THIS EVENING INTO SATURDAY NIGHT.
FIRE WEATHER...
VERY GUSTY NORTHWEST WINDS WILL CONTINUE THROUGH THE DAY. DRY AIR
IS EXPECTED TO ADVECT INTO THE REGION...DROPPING DEW POINT TEMPS
INTO THE TEENS AND SINGLE DIGITS. THIS WILL COMBINE WITH HIGHS IN
THE 40S TO PRODUCE MINIMUM RELATIVE HUMIDITY VALUES AROUND 20
PERCENT...LOWEST IN SW NEB. WILL CONTINUE THE RED FLAG WARNING FOR
ALL BUT ZONE 208...WHERE RH VALUES CLOSER TO 30 PERCENT ARE
EXPECTED. ALTHOUGH THE AREA MAY NOT REACH THE TYPICAL WIDESPREAD
RH MINIMUM PERCENTAGES OF 15 PERCENT NEEDED FOR A RED FLAG...THE
COMBINATION OF WIND GUSTS ABOVE 50 MPH...THE VERY DRY FUELS AND
STILL LOW RH VALUES AROUND 20 PERCENT WARRANT THE HEADLINE. THERE
IS A SMALL CHANCE THE DRIER AIR IS DELAYED...WHICH WOULD RESULT IN
WIDESPREAD MINIMUM RH PERCENTAGES IN THE 30S. LOW CONFIDENCE ON
THIS SCENARIO AND WANT TO ERROR ON THE SIDE OF CAUTION.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...HIGH WIND WARNING UNTIL 6 PM
CST /5 PM MST/ THIS EVENING FOR
NEZ004>010-022>029-035>038-056>059-069>071-094.
RED FLAG WARNING FROM NOON CST /11 AM MST/ TODAY TO 6 PM CST /5
PM MST/ THIS EVENING FOR NEZ204-206-209-210-219.
&&
$$
AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
536 AM CST SAT NOV 26 2011
.AVIATION...
EXPECT VFR CONDITIONS AND VERY GUSTY NORTHWEST TODAY. COLD FRONT
HAS PUSHED WELL TO THE EAST WITH HIGH BUILDING OVER THE ROCKIES
WHICH IS RESULTING IN WIDESPREAD NORTHWEST WINDS ON THE INCREASE.
LOCALLY GUSTS ABOVE 40 KTS WILL CONTINUE INTO THE MID MORNING
HOURS...THEN WIDESPREAD GUSTS ABOVE 40 KTS AND APPROACHING 50 KTS
ARE EXPECTED. SUNSET WILL ALLOW FOR WINDS TO DIMINISH QUICKLY AS
THE BOUNDARY LAYER DECOUPLES. BKN/OVC CIGS AROUND 10K FT AGL WILL
PUSH EAST BY MID MORNING OR EARLY AFTERNOON. ONCE SKIES
CLEAR...EXPECT THEM TO REMAIN CLR INTO SATURDAY NIGHT.
&&
.PREV DISCUSSION... /ISSUED 312 AM CST SAT NOV 26 2011/
DISCUSSION...
SHORT TERM...
BUFKIT IS ON TRIAL TODAY AS IT CONTINUES TO ADVERTISE VERY STRONG
WINDS...40 TO 45 KTS AT 1000 TO 1500 FT AGL. THIS SHOULD TRANSLATE
TO SFC WINDS OF 40 MPH OR STRONGER AND ALL MODELS IN BUFKIT SHOW
THIS.
THE MODEL GUIDANCE AND DIRECT OUTPUT HAVE BEEN WOBBLING SHOWING
WIND SPEEDS RUNNING ABOVE AND BELOW HIGH WIND CRITERIA. BUFKIT HAS
BEEN VERY RELIABLE THOUGH SUGGESTING HIGH WINDS WILL DEVELOP.
THE LATEST MAV MET GUIDANCE WIND SPEEDS HAVE SLOWED
SOME...SUGGESTING A HIGH END WIND ADVISORY ACROSS MOST AREAS. THE
EXCEPTION AT KBBW. THE 06Z NAM HOWEVER INDICATES 65 KT WINDS AT
800MB...THE APPROXIMATE MIXING DEPTH EXPECTED ACROSS NCNTL NEB
THIS AFTN. A CORRIDOR OF HIGH WINDS IS EXPECTED TO DEVELOP FROM
KVTN SSE THROUGH KBBW TODAY. DEEPER VERTICAL MIXING IS EXPECTED TO
PRODUCE HIGH WIND GUSTS ACROSS SWRN NEB THIS AFTERNOON ALSO. A
BLEND OF HRRR AND NAMDNG WIND GUST DATA PRODUCED GUSTS TO 55 MPH.
A FEW KNOTS WERE ADDED TO THE FCST TO BRING GUSTS SPEEDS TO 60 MPH
WHICH IS CERTAINLY REACHABLE GIVEN THE 65 KT WINDS AT 800MB SHOWN
IN THE NAM. ALSO KTIF AND KLBF GUSTED TO 47 MPH BETWEEN 8 AND 9Z
BUT HRRR SUGGESTED GUSTS TO 58 MPH WOULD DEVELOP. THE 06Z NAM
FRH68 DATA SUGGESTED 35 KTS IN LOWEST 35 MB THIS AFTERNOON AT
KLBF...ROUGHLY 35 MPH AT THE SFC. 35 MPH IN THE VALLEY SHOULD
EQUATE TO 40 MPH IN THE SANDHILLS NORTH AND SOUTH OF TOWN.
THE HIGH WIND WARNING APPEARS TO BE ON TRACK ACROSS A GOOD
PORTION OF THE FORECAST AREA. WEAKNESSES IN THE WIND FIELDS WERE
NOTED A BOYD AND WHEELER COUNTIES AND ACROSS SHERIDAN COUNTY.
WIND SPEEDS SHOULD DROP OFF RAPIDLY BETWEEN 4 AND 6 PM CST AS
VERY DRY AIR WILL MOVE IN THIS AFTN. BY SUNDAY MORNING 1035MB HIGH
PRESSURE SHOULD BE ACROSS THE FCST AREA AND WINDS IN THE VALLEYS
SHOULD FALL OFF TO LESS THAN 10 MPH. LOWS IN THE TEENS SHOULD BE
COMMON.
LONG TERM...
ANOTHER STRONG PACIFIC COLD FRONT WILL MOVE THROUGH THE FCST AREA
MONDAY WITH WINDS INCREASING...PERHAPS TO WIND ADVISORY
CRITERIA...30 MPH. MIX DOWN WIND TOOLS PRODUCED WINDS NEAR 30 MPH
AND GFS AND ECMWF SHOW SOME 50 KT WINDS AT 850MB MONDAY AFTERNOON.
FOR NOW A LIMITER WAS USED FOR 20 TO 30 MPH WIND SPEEDS AND LATER
FCSTS CAN ADJUST UP IF NECESSARY. BY TUESDAY MORNING 1035 MPH HIGH
PRESSURE IS CENTERED SOMEWHERE BETWEEN SD AND NERN COLO WITH LOWS
IN THE TEENS. THIS HIGH WILL THEN MOVE OFF TO THE SOUTHEAST TO BE
FOLLOWED BY A STRONGER MORE ARCTIC TYPE HIGH PRESSURE SYSTEM
WEDNESDAY NIGHT AND THURSDAY. THE FRONT APPEARS TO BE CARRYING
SOME MOISTURE WITH IT FROM THE HIGH LATITUDES. SO WE CONTINUE THE
FORECAST FOR SCATTERED SNOW SHOWERS. TEMPS AHEAD OF THE FRONT
APPEAR TO BE COLD ENOUGH FOR SNOW VS FREEZING DRIZZLE CHANGING TO
SNOW. EITHER WAY VERY LIGHT PCPN AMOUNTS ARE EXPECTED WITH THE
FRONT AND MAINLY ACROSS THE NORTHWEST ZONES.
MAX TEMPS TODAY THROUGH WEDNESDAY WILL BE MOSTLY IN THE 40S TO
LOWER 50S. BEHIND THE ARCTIC FRONT THURSDAY AND FRIDAY HIGHS
REACH ONLY INTO THE 30S.
SO THE GEM...GFS...ECMWF AND GEF ARE IN VERY GOOD AGREEMENT
THROUGH WEDNESDAY. THEREAFTER...TIMING PROBLEMS DEVELOP WITH THE
ARCTIC FRONT WHICH APPEAR TO BE RELATED TO DISTURBANCES UPSTREAM
AND DOWNSTREAM ACROSS THE WRN AND ERN U.S. THE GFS APPEARED TO BE
THE MOST RATIONAL SOLN. TIMING-WISE IT WAS SLOWER THAN THE GEM
AND FASTER THAN THE ECMWF.
AVIATION...
EXPECT VFR CONDITIONS AND VERY GUSTY NORTHWEST TODAY. COLD FRONT HAS
PUSHED WELL TO THE EAST WITH WIDESPREAD NORTHWEST WINDS ON THE
INCREASE. LOCALLY GUSTS ABOVE 40 KTS WILL CONTINUE INTO THE MID
MORNING HOURS...THEN WIDESPREAD GUSTS ABOVE 40 KTS ARE EXPECTED.
SUNSET WILL ALLOW FOR WINDS TO DIMINISH QUICKLY AS THE BOUNDARY
LAYER DECOUPLES. BKN/OVC CIGS AROUND 10K FT AGL WILL PUSH EAST BY
MID MORNING OR EARLY AFTERNOON. THERE IS A POSSIBILITY FOR A SCT/BKN
VFR CU FIELD THIS AFTERNOON...HOWEVER LOW CONFIDENCE IN ITS
DEVELOPMENT AS DRY AIR ADVECTS INTO THE REGION. SKIES SHOULD BE
CLEAR BY THIS EVENING INTO SATURDAY NIGHT.
FIRE WEATHER...
VERY GUSTY NORTHWEST WINDS WILL CONTINUE THROUGH THE DAY. DRY AIR
IS EXPECTED TO ADVECT INTO THE REGION...DROPPING DEW POINT TEMPS
INTO THE TEENS AND SINGLE DIGITS. THIS WILL COMBINE WITH HIGHS IN
THE 40S TO PRODUCE MINIMUM RELATIVE HUMIDITY VALUES AROUND 20
PERCENT...LOWEST IN SW NEB. WILL CONTINUE THE RED FLAG WARNING FOR
ALL BUT ZONE 208...WHERE RH VALUES CLOSER TO 30 PERCENT ARE
EXPECTED. ALTHOUGH THE AREA MAY NOT REACH THE TYPICAL WIDESPREAD
RH MINIMUM PERCENTAGES OF 15 PERCENT NEEDED FOR A RED FLAG...THE
COMBINATION OF WIND GUSTS ABOVE 50 MPH...THE VERY DRY FUELS AND
STILL LOW RH VALUES AROUND 20 PERCENT WARRANT THE HEADLINE. THERE
IS A SMALL CHANCE THE DRIER AIR IS DELAYED...WHICH WOULD RESULT IN
WIDESPREAD MINIMUM RH PERCENTAGES IN THE 30S. LOW CONFIDENCE ON
THIS SCENARIO AND WANT TO ERROR ON THE SIDE OF CAUTION.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...HIGH WIND WARNING UNTIL 6 PM
CST /5 PM MST/ THIS EVENING FOR
NEZ004>010-022>029-035>038-056>059-069>071-094.
RED FLAG WARNING FROM NOON CST /11 AM MST/ TODAY TO 6 PM CST /5
PM MST/ THIS EVENING FOR NEZ204-206-209-210-219.
&&
$$
AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
523 AM CST SAT NOV 26 2011
.AVIATION...12Z TAFS FOR KOFK...KOMA...KLNK.
MAIN CONCERN WILL BE VERY GUSTY NORTHWEST SFC WINDS THRU THE DAY.
GUSTS ARE EXPECTED TO INCREASE TO NEAR 40 KTS BY LATE MORNING AND
EARLY AFTERNOON. MVFR CONDITIONS ARE EXPECTED THIS MORNING FOR
KOFK AND KOMA HOWEVER SHOULD IMPROVE TO VFR BY EARLY AFTERNOON.
WINDS WILL BEGIN TO DIMINISH LATER THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 325 AM CST SAT NOV 26 2011/
DISCUSSION...
MAIN FORECAST CONCERN IS WIND TODAY. WATER VAPOR IMAGERY EARLY THIS
MORNING SHOWED A FAIRLY IMPRESSIVE TROUGH EXTENDING FROM SASKATCHEWAN
DOWN INTO MEXICO. 500 MB HEIGHT FALLS WERE AROUND OR IN EXCESS OF
100 METERS FROM SOUTHWEST NEBRASKA TO WEST TEXAS LAST EVENING. A FEW
THUNDERSTORMS WERE NOTED NEAR THE KANSAS/OKLAHOMA BORDER. A COLD
FRONT STRETCHED FROM LOW PRESSURE OVER SOUTHERN MINNESOTA DOWN INTO
WESTERN OKLAHOMA.
THE TROUGH AND FRONT WILL BOTH CONTINUE TO MOVE EAST TODAY...WITH A
TIGHT PRESSURE GRADIENT AND STRONG WINDS SPREADING EAST ACROSS THE
AREA. DELAYED WIND ADVISORY A FEW HOURS FOR PARTS OF THE AREA THIS
MORNING...BUT OTHERWISE WIND FORECAST IS SIMILAR TO PREVIOUS GRIDS.
THE 06Z RUC MODEL DID SHOW SOME LIGHT PRECIPITATION MOVING INTO PARTS
OF NORTHEAST NEBRASKA THROUGH 18Z. OTHERWISE...THE SHOWERS IN FAR
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SHOULD MOVE OUT VERY EARLY
THIS MORNING. MUCH COLDER AIR WILL MOVE INTO THE AREA TODAY. LOWS
TONIGHT SHOULD BOTTOM OUT IN THE UPPER TEENS TO MID 20S. WINDS WILL
REMAIN BRISK AT LEAST EARLY TONIGHT BUT MOST LIKELY BELOW ADVISORY
LEVELS. AS HIGH PRESSURE AT THE SURFACE BUILDS INTO THE AREA ON
SUNDAY...WINDS WILL DECREASE. EXPECT WEAK RETURN FLOW TO SETUP LATE
SUNDAY NIGHT...BUT IS NOT EXPECTED TO BE STRONG ENOUGH TO KEEP LOWS
UP MUCH ABOVE MOS GUIDANCE.
MILDER AIR SHOULD BE OVER THE AREA MONDAY...WITH HIGHS IN THE UPPER
40S AND LOWER 50S. NEXT COLD FRONT PUSHES THROUGH MONDAY NIGHT...BUT
SHOULD NOT PRODUCE ANY PRECIPITATION. KEPT TUESDAY AND WEDNESDAY DRY
BUT ADDED A SLIGHT CHANCE OF LIGHT SNOW FOR ABOUT THE NORTHERN HALF
OF THE FORECAST AREA THURSDAY. 00Z GFS WAS THE BEST MODEL DEPICTING
THAT SCENARIO.
MILLER
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ015-033-034-
043>045-050>053-065>068-078-088>093.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ011-012-016>018-
030>032-042.
IA...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ043-055-056-069-
079-080-090-091.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
325 AM CST SAT NOV 26 2011
.DISCUSSION...
MAIN FORECAST CONCERN IS WIND TODAY. WATER VAPOR IMAGERY EARLY THIS
MORNING SHOWED A FAIRLY IMPRESSIVE TROUGH EXTENDING FROM SASKATCHEWAN
DOWN INTO MEXICO. 500 MB HEIGHT FALLS WERE AROUND OR IN EXCESS OF
100 METERS FROM SOUTHWEST NEBRASKA TO WEST TEXAS LAST EVENING. A FEW
THUNDERSTORMS WERE NOTED NEAR THE KANSAS/OKLAHOMA BORDER. A COLD
FRONT STRETCHED FROM LOW PRESSURE OVER SOUTHERN MINNESOTA DOWN INTO
WESTERN OKLAHOMA.
THE TROUGH AND FRONT WILL BOTH CONTINUE TO MOVE EAST TODAY...WITH A
TIGHT PRESSURE GRADIENT AND STRONG WINDS SPREADING EAST ACROSS THE
AREA. DELAYED WIND ADVISORY A FEW HOURS FOR PARTS OF THE AREA THIS
MORNING...BUT OTHERWISE WIND FORECAST IS SIMILAR TO PREVIOUS GRIDS.
THE 06Z RUC MODEL DID SHOW SOME LIGHT PRECIPITATION MOVING INTO PARTS
OF NORTHEAST NEBRASKA THROUGH 18Z. OTHERWISE...THE SHOWERS IN FAR
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SHOULD MOVE OUT VERY EARLY
THIS MORNING. MUCH COLDER AIR WILL MOVE INTO THE AREA TODAY. LOWS
TONIGHT SHOULD BOTTOM OUT IN THE UPPER TEENS TO MID 20S. WINDS WILL
REMAIN BRISK AT LEAST EARLY TONIGHT BUT MOST LIKELY BELOW ADVISORY
LEVELS. AS HIGH PRESSURE AT THE SURFACE BUILDS INTO THE AREA ON
SUNDAY...WINDS WILL DECREASE. EXPECT WEAK RETURN FLOW TO SETUP LATE
SUNDAY NIGHT...BUT IS NOT EXPECTED TO BE STRONG ENOUGH TO KEEP LOWS
UP MUCH ABOVE MOS GUIDANCE.
MILDER AIR SHOULD BE OVER THE AREA MONDAY...WITH HIGHS IN THE UPPER
40S AND LOWER 50S. NEXT COLD FRONT PUSHES THROUGH MONDAY NIGHT...BUT
SHOULD NOT PRODUCE ANY PRECIPITATION. KEPT TUESDAY AND WEDNESDAY DRY
BUT ADDED A SLIGHT CHANCE OF LIGHT SNOW FOR ABOUT THE NORTHERN HALF
OF THE FORECAST AREA THURSDAY. 00Z GFS WAS THE BEST MODEL DEPICTING
THAT SCENARIO.
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK AND KOFK.
VFR CONDITIONS ARE FORECAST AT KOFK THROUGH THE FORECAST PERIOD. SOME
MVFR CEILINGS MAY OCCUR AT KOMA AND KLNK AFTER 18Z. STRONG SURFACE
COLD FRONT WILL MOVE ACROSS THE AREA WITH STRONG NORTHWEST WINDS
SHOULD MOVE ACROSS KOFK BY 08Z...KLNK BY 11Z AND KOMA BY 15Z. WINDS
DURING THE DAY ON SATURDAY ARE EXPECTED TO GUST OUT OF THE NORTHWEST
BETWEEN 35 TO 40 KT. LOW LEVEL WIND SHEAR IS LIKELY FROM 08Z TO 15Z
AT KOFK BEFORE TURBULENT MIXING ALLOWS WINDS TO INCREASE AT THE
SURFACE.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY FROM 8 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR NEZ015-033-034-043>045-050>053-065>068-078-088>093.
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ011-012-016>018-
030>032-042.
IA...WIND ADVISORY FROM 8 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR IAZ043-055-056-069-079-080-090-091.
&&
$$
DISCUSSION...MILLER
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
307 AM CST SAT NOV 26 2011
.SHORT TERM...TODAY THROUGH MONDAY NIGHT. THE MAIN CONCERN IN THE
SHORT TERM FORECAST PERIOD WILL BE WINDS TODAY ALONG WITH THE
POSSIBILITY OF RED FLAG CONDITIONS. THE RED FLAG CONCERNS WILL BE
ADDRESSED IN THE FIRE WEATHER PORTION OF THE DISCUSSION LOCATED
BELOW.
A LARGE MID LEVEL TROUGH MOVING ACROSS THE CENTRAL UNITED STATES
THIS MORNING IS PUSHING A STRONG COLD FRONT ACROSS THE REGION. MSAS
3 HOUR PRESSURE CHANGE ANALYSIS SHOWS PRESSURE RISES NEAR 7
MILLIBARS BEHIND THE FRONT WHICH IS HELPING BRING A NICE SURGE OF
WINDS AS THE BOUNDARY PASSES. WINDS WILL LIKELY SETTLE DOWN TO SOME
DEGREE THIS MORNING BEHIND THE FRONT...HOWEVER IT WILL NOT TAKE LONG
FOR THE WINDS TO INCREASE AGAIN AS MIXING COMMENCES THIS MORNING.
ALL SIGNS STILL POINT TO A DECENT WIND EVENT FOR TODAY WITH A STRONG
SURFACE PRESSURE GRADIENT DEVELOPING DUE TO LOW PRESSURE TO THE
EAST...AND HIGH PRESSURE TO THE WEST.
THE PRIMARY CONCERN SURROUNDS THE GOING HIGH WIND WARNING AND
WIND ADVISORY...AND POTENTIAL CHANGES/ADJUSTMENTS TO THE HEADLINES
FOR TODAY. NAM PROXIMITY SOUNDINGS SUGGEST MIXING TO NEAR H8 IS
LIKELY ACROSS A MAJORITY OF THE FORECAST AREA TODAY...WITH 50 TO
60 KTS OF WIND EXPECTED AT THAT LEVEL. THE FLOW WILL BE FAIRLY
UNIDIRECTIONAL IN THE MIXED LAYER...SO SOME OF THE THE STRONG
WINDS COULD POTENTIALLY TRANSFER TO THE SURFACE. THE HEART OF THE
STRONGER WINDS ARE SHOWN TO RESIDE ACROSS WESTERN PORTIONS OF THE
FORECAST AREA...AND THE CURRENT HIGH WIND WARNING COVERS THAT
WELL. WILL GO AHEAD AND LEAVE THE HEADLINES IN THEIR PRESENT
CONFIGURATION...THOUGH THE NEXT SHIFT WILL OBVIOUSLY HAVE TO WATCH
TRENDS AS THE STRONGER H8 WINDS SHIFT SOUTHEAST THIS AFTERNOON.
A SMALLER CONCERN FOR TODAY WILL BE THE POSSIBILITY OF ANY LINGERING
FLURRIES OR SPRINKLES AS THE LEFT EXIT REGION OF A 100KT UPPER
JET SEGMENT SHIFTS THROUGH THE AREA. THE LATEST SREF AND NCEP 4KM
WRF KEEP IT DRY AFTER 12Z TODAY...WHILE THE GFS AND NOW 26.06Z
NAM SUGGESTS THERE COULD BE LINGERING LIGHT PRECIPITATION IN PARTS
OF NORTH CENTRAL KANSAS THIS MORNING...WHILE THE RUC DEVELOPS
LIGHT QPF IN EASTERN PARTS OF THE FORECAST AREA. CROSS SECTIONS
OF RELATIVE HUMIDITY/OMEGA FROM THE NAM REVEAL DRY LOW LEVELS
WHICH WILL BE TOUGH TO OVERCOME...ESPECIALLY AS THE FORCING
WEAKENS...SO WOULD RATHER CARRY A NON MEASURABLE EVENT SUCH AS
SPRINKLES OR FLURRIES. H85 TEMPERATURES QUICKLY FALL BELOW
FREEZING THIS MORNING...HOWEVER ABOVE FREEZING H925 TEMPERATURES
WILL PERSIST...SO WILL GO WITH SPRINKLES/FLURRIES IN THE GRIDS.
THE STRONGEST OF THE WINDS SHOULD SUBSIDE BY EARLY EVENING AS MIXING
BEGINS TO DIMINISH. H5 HEIGHTS BEGIN TO RISE TONIGHT...WITH WARMER
AIR GRADUALLY RETURNING FOR SUNDAY AND MONDAY. IN FACT...H85
TEMPERATURES RISE FROM -5 DEGREES CELSIUS TONIGHT...TO NEARLY +10
DEGREES CELSIUS ON MONDAY IN PORTIONS OF THE FORECAST AREA. WILL
AIM FOR HIGHS IN THE MID 40S TO LOWER 50S ON SUNDAY...WITH 50S ON
MONDAY.
ANOTHER MID LEVEL WAVE HELPS KNOCK DOWN THE RIDGE MONDAY AFTERNOON
INTO MONDAY NIGHT...WITH ANOTHER COLD FRONT PLOWING THROUGH THE
AREA. MOISTURE APPEARS LIMITED WITH THE PASSAGE OF THE WAVE/FRONT
AND WILL MAINTAIN A DRY FORECAST AS IT PASSES. WINDS WILL AGAIN
BECOME GUSTY AS THE FRONT PASSES...BUT CURRENTLY IT APPEARS SPEEDS
SHOULD STAY BELOW ADVISORY LEVELS.
.LONG TERM...TUESDAY THROUGH FRIDAY.
MODELS NOT IN TOO BAD OF AGREEMENT AT THE START OF THE LONG TERM
PERIOD...WITH NORTHWESTERLY FLOW SET UP IN THE UPPER LEVELS AS A LOW
PRESSURE SYSTEM SPINS OVER THE SOUTHEASTERN CONUS AND A RIDGE AXIS
SETS UP OVER THE WEST COAST. WITH NO DISTURBANCES EXPECTED TO PUSH
THROUGH THE REGION...FORECAST FOR TUESDAY REMAINS DRY. GETTING INTO
TUESDAY NIGHT THROUGH THURSDAY...EXPECTING TO SEE SHORTWAVE UPPER
LEVEL RIDGING BUILD INTO THE CENTRAL PLAINS EXTENDING FROM THE AREA
OF HIGH PRESSURE CENTERED JUST OFF THE SRN COAST OF CA...BETWEEN THE
LOW PRESSURE CONTINUES TO PUSH NORTHEAST TOWARD THE EAST COAST AND
ANOTHER DISTURBANCE MOVING FROM THE PAC NW INTO THE ROCKIES.
A LITTLE MORE UNCERTAINTY ARISES INTO THURSDAY AND FRIDAY WITH THE
LATEST MODEL RUNS HAVING A FEW DIFFERENCES. THE GENERAL STORY IS
THE DISTURBANCE WHICH HAS SHIFTED INTO THE ROCKIES BECOMES
SPLIT...WITH A CLOSED LOW DEVELOPING OVER THE WRN/SWRN CONUS...BUT
MODELS VARY ON THE TIMING AND LOCATION OF THE LOW AND WHAT HAPPENS
WITH THE NORTHERN ENERGY. THE GFS PUSHES THE NORTHERN ENERGY
FURTHER SOUTH INTO THE REGION...WHILE THE ECMWF SHOWS MORE RIDGING
HELPING TO PUSH IT FURTHER EAST. INTRODUCED SMALL PRECIPITATION
CHANCES ACROSS THE NORTHERN PORTIONS OF THE CWA TO ACCOUNT FOR THIS
DISTURBANCE IN THE REGION...BUT KEPT IT CONFINED TO THE DAYTIME
HOURS ON THURSDAY. TEMPERATURES SUGGEST THE PTYPE WOULD BE SNOW.
ANY PRECIPITATION WOULD NOT STICK AROUND LONG...AND KEPT THURSDAY
NIGHT AND FRIDAY DRY.
WHILE A BUMP UP IN TEMPERATURES IS EXPECTED ON WEDNESDAY WITH THE
RIDGING SET UP AND HIGHS IN THE UPPER 40S TO LOWER/MID
50S...COMPARED TO THE LOWER/MID 40S ON TUESDAY...A COLD FRONT IS
EXPECTED TO PUSH THROUGH THE CWA EARLY THURSDAY. THE COOLER AIR
ACCOMPANYING THE FRONT LOOKS TO DROP HIGHS FOR THURSDAY INTO THE MID
30S TO LOWER 40S...WITH MID 30S EXPECTED FOR FRIDAY.
&&
.AVIATION...06Z TAF. PRIMARY FORECAST CONCERN FOR THIS TAF PERIOD
CONTINUES TO LIE WITH STRONG WINDS EXPECTED. SURFACE COLD FRONT
CURRENTLY PUSHING ITS WAY ACROSS THE CWA...WITH WINDS AT THE
TERMINAL ALREADY HAVING SHIFTED TO THE WEST...AND WILL SOON BE OUT
OF THE NORTHWEST. BETWEEN A TIGHTENING PRESSURE GRADIENT/PRESSURE
RISES AND A CORRIDOR OF STRONGER WINDS ALOFT...EXPECTING WINDS TO
BE ON THE INCREASE...TOPPING OUT IN THE MID MORNING THROUGH MID
AFTERNOON HOURS. SUSTAINED SPEEDS OF 30 TO 40 MPH AND GUSTS NEAR
50 MPH ARE EXPECTED. VFR CONDITIONS ARE EXPECTED WITH CLOUD COVER
REMAINING IN THE MID/UPPER LEVELS...BUT CANT COMPLETELY RULE OUT A
BRIEF PERIOD OF MVFR CEILINGS WITH THE STRATUS ACCOMPANYING THE
SURFACE FRONT. OTHERWISE CLEARING SKIES ARE EXPECTED BY
MIDDAY...CONTINUING THROUGH THE REMAINDER OF THE TAF PERIOD.
&&
.FIRE WEATHER...AS STATED ABOVE WINDS TODAY WILL EASILY EXCEED
THE 25 KT GUST CRITERIA NEEDED FOR A RED FLAG WARNING. THE BIGGEST
CONCERN WILL BE RELATIVE HUMIDITY VALUES DROPPING TO 20 PERCENT OR
LESS. THE NAM AND GFS HAVE BOTH COME IN WITH HIGHER SURFACE
DEWPOINTS ON THE 00Z RUNS...AND THIS TREND IS ALSO EVIDENT EVEN
WHEN MIXING DEWPOINTS ALOFT TO THE SURFACE. THAT BEING SAID...AM
STILL CONCERNED ABOUT FIRE WEATHER ISSUES TODAY...ESPECIALLY WITH
THE LATEST ECMWF STILL SUPPORTING LOWER DEWPOINTS THIS AFTERNOON.
WILL HOLD ONTO THE LOWER DEWPOINTS SHOWN BY THE CURRENT FORECAST
AND LATEST ECMWF AND KEEP THE RED FLAG WARNING IN PLACE FOR THIS
AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ041-048-049-063-
064-076-077-086-087.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ039-040-046-
047-060>062-072>075-082>085.
RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR
NEZ039-040-046-047-060>062-072>075-082>085.
KS...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR KSZ007-019.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR KSZ005-006-017-
018.
RED FLAG WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR
KSZ005>007-017>019.
&&
$$
SHORT TERM/FIRE WEATHER...KING
LONG TERM/AVIATION...ADO
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1053 PM EST SUN NOV 27 2011
.SYNOPSIS...
WEAKENING FRONT AND INCREASING MOISTURE TONIGHT INTO MONDAY...WILL
RESULT IN THICKENING CLOUDS WITH SOME LIGHT SHOWERS OR PATCHY
DRIZZLE. HOWEVER...OUR MAIN BATCH OF RAIN WILL COME FROM A LOW
PRESSURE SYSTEM MOVING THROUGH THE REGION TUESDAY AFTERNOON
THROUGH TUESDAY NIGHT. SOME SHOWERS MAY LINGER INTO WEDNESDAY.
BEHIND THE SYSTEM...TEMPERATURES WILL COOL DOWN TO NEAR NORMAL
LEVELS DURING THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
1030 PM UPDATE... IN THE LAST COUPLE OF HRS...PCPN HAS STARTING
EDGING SLOWLY BACK TWDS THE W. BEING THAT THE SFC FRNT HAS
EFFECTIVELY STALLED ACRS SRN ONT/LK ERIE/OH ATTM...AND THAT DEEP-LYRD
S TO SWLY FLOW WILL BE INCRG IN THE NEXT 12-24 HRS...WE DON`T
EXPECT ANY EWD ADVANCEMENT IN THE NEAR-TERM. WE`VE ADJUSTED
POP/WX GRIDS ACCORDINGLY.
ALSO...TEMPS HAVEN`T FALLEN MUCH AT ALL SO FAR THIS EVE...AND
WE`VE NUDGED OVERNIGHT MINS UP SVRL DEGREES.
8 PM UPDATE... THE LEADING EDGE OF THE -SHRA HAVE MADE IT TO ABT
A KELZ-KPEO-KSYR-KRME LN ATTM. NEAR-TERM NWP GUIDANCE CONTINUES TO
INDICATE THAT ANY FURTHER EWD PUSH TO THE LGT PCPN OVERNIGHT WILL
BE SMALL...AND BASED ON RECENT RADAR TRENDS...WE`RE INCLINED TO GO
ALG WITH THIS THINKING. THUS...SCTD TO NUMEROUS WORDING FOR -SHRA
WILL BE INDICATED IN OUR NRN/WRN ZNS OVERNIGHT...WITH LTL IF ANY
PCPN FARTHER TO THE S AND E...SAVE FOR SOME PATCHY DRZL IN PTNS OF
THE CATSKILLS AND POCONOS TWDS 12Z.
ONLY MINOR TWEAKS WERE MADE TO TEMP/DEW PT GRIDS THROUGH 06Z.
PREV DISC... 4 PM UPDATE...TEMPERATURES TOPPED OUT ROUGHLY 13 TO 17 DEGREES
ABOVE NORMAL...BEING HELD BACK FROM GOING FURTHER ONLY BECAUSE OF
THICKENING HIGH CLOUDS. FRONT IS APPROACHING FROM THE WEST BUT
STRUGGLING...WITH MAINLY ONLY VIRGA SO FAR EXCEPT FOR EXTREME
WESTERN PA AND NY. ONE WEAK WAVE TRAVELING THROUGH THE BRISK
SOUTHWEST FLOW WILL MANAGE TO SKIM STEUBEN COUNTY AND SOME OF THE
WESTERN FINGER LAKES WITH LIGHT SHOWERS DURING THE NEXT FEW
HOURS...THE REST OF THE AREA WILL CONTINUE TO SEE THICKENING HIGH
TO MID LEVEL CLOUDS.
A BIT OF A SQUEEZE PLAY TONIGHT INTO MONDAY MORNING...AS FRONT
STALLS OUT IN OUR NORTHWESTERN ZONES WITH LIGHT SHOWERS COMING OUT
OF TOP-DOWN MOISTENING FROM UPPER LEVELS...YET ALSO SHALLOW MARINE
MOISTURE ATTEMPTS TO RIDE IN ON SOUTHERLY LOW LEVEL FLOW. RUC AND
18Z NAM HAVE BACKED OFF SOMEWHAT ON THIS IDEA HOWEVER...WITH LIGHT
SURFACE WIND VEERING TO INCLUDE SOME WESTERLY COMPONENT...WHICH IS
NOT AS FAVORABLE FOR MARINE MOISTURE TO REACH INTO THE AREA. I
HAVE LIMITED PATCHY DRIZZLE MENTION TO SOME OF THE
POCONOS/CATSKILLS REGION SUSCEPTIBLE TO UPSLOPE FLOW...LATER
TONIGHT INTO EARLY MONDAY MORNING. FARTHER NORTHWEST...NOT AS
MUCH LOW LEVEL MOISTURE...YET ENOUGH MOISTURE IN MID/HIGH LEVELS
FOR LIGHT SHOWERS. CLOUDS HANG AROUND THROUGH MONDAY
AFTERNOON...THOUGH WITH ANY SHOWERS DIMINISHING AS WEAK FRONT
BEGINS TO SLOWLY SHIFT NORTHWARD.
WITH AMOUNT OF CLOUD COVER...ESPECIALLY LATE TONIGHT THROUGH
MONDAY...WILL BE STAYING ON WARM SIDE OF GUIDANCE FOR LOWS
TONIGHT...AND COOLER THAN THE MODELS FOR HIGHS MONDAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
GOOD MODEL AGREEMENT ON BIG PICTURE FOR UPPER LOW TO PROGRESSIVELY
MOVE THROUGH THE AREA...WITH MODEL CONSENSUS GIVING US OUR MAIN
BATCH OF RAIN LATE TUESDAY INTO TUESDAY NIGHT. WHILE THERE WILL BE
AN ATLANTIC SUBTROPICAL FEED OF MOISTURE...SPEED OF SYSTEM WILL
MINIMIZE ANY THREAT FOR WATER PROBLEMS. AT THIS TIME WE ARE
EXPECTING AREAL AVERAGE OF LESS THAN AN INCH OF RAINFALL.
HOWEVER...SOME MARGINAL INSTABILITY EVIDENT AS NEGATIVELY TILTED
FRONT COMES THROUGH TUESDAY EVENING...TO THE POINT THAT LATER
SHIFTS MAY NEED TO CONSIDER ADDING MENTION OF THUNDER. WITH
DELAYED TIMING OF FRONT...TEMPERATURES LOOK TO GET QUITE WARM ON
TUESDAY.
COLD CORE OF UPPER LOW PASSES DIRECTLY OVERHEAD WEDNESDAY...AND
EXPECTING SCATTERED SHOWERS IN THE WRAP AROUND MOISTURE OF THE
COMMA HEAD. DESPITE STRONG COLD AIR ADVECTION...925-850MB
TEMPERATURES DO NOT SUPPORT SHOWERS CHANGING OVER TO SNOW DURING
THE DAY WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
PERIOD BEGINS WITH VIGOROUS STORM SYSTEM EXITING TO THE EAST, AND
HIGH PRESSURE BUILDING NORTHWARD FROM THE LOWER OHIO VALLEY.
A WEAK LOW PRESSURE CENTER AND ASSOCIATED FRONT WILL MOVE OVER
LAKE ONTARIO EARLY FRIDAY, BRINGING WITH IT A CHANCE FOR A RAIN OR
SNOW SHOWER.
A TROF WILL DIG INTO ONTARIO PROVINCE SATURDAY INTO SUNDAY, WITH
SOME JET ACTIVITY ALONG THE US/CANADIAN BORDER. THIS WILL BRING
A BETTER CHANCE FOR SNOW SHOWERS, ESPECIALLY OVER NY STATE, THIS
WEEKEND.
TEMPERATURES WILL FLUCTUATE BETWEEN SYSTEMS, BUT OVERALL WILL BE
TRENDING BACK TOWARD SEASONABLY COOL READINGS.
&&
.AVIATION /04Z MONDAY THROUGH FRIDAY/...
A STALLED FRONTAL SYSTEM STRETCHES FROM LOWER ONTARIO, DOWN LAKE
ERIE. SHOWERS ARE MOVING NORTHEASTWARD ALONG THE FRONT, AND WILL
AFFECT OUR TERMINALS LATER TONIGHT WHEN THE FRONT PUSHES EASTWARD.
THE EASTWARD PUSH OF THE FRONT WILL NOT LAST FOR LONG, AS IT IS
FORECAST TO RETROGRADE WESTWARD OVERNIGHT. HOWEVER SOME DRIZZLE
AND SCATTERED SHOWER ACTIVITY WILL AFFECT THE BGM, SYR, ITH, ELM,
AND RME TERMINALS WELL AFTER DARK. CEILINGS WILL SLOWLY DEGRADE TO
MVFR TERRITORY LATE TONIGHT, BEFORE RISING TO A MOSTLY CLOUDY VFR
DECK TOWARD NOON MONDAY.
WE HAVE REMOVED THE POTENTIAL FOR A MARINE LAYER MAKING IT TO AVP
OVERNIGHT, AS THE LATEST NAM12 AND RUC RUNS DISAGREE WITH THE
PREVIOUS GFS INSISTENCE OF A MARINE LAYER. CURRENT UPSTREAM OBS
SHOW SIGN OF THE LAYER COMING ASHORE.
HOWEVER AVP WILL HAVE SOME MVFR TO BORDERLINE IFR RESTRICTIONS
EARLY MONDAY MORNING IN DRIZZLE AND LIGHT FOG.
OUTLOOK...
MON NGT...IFR/MVFR. PERIODS OF RAIN AND FOG.
TUE THRU THU...PATCHY MVFR IN SCT -SHRA. SCT -SHSN AND MVFR/BRIEF
IFR POSSIBLE BEGINNING WED.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MLJ/MDP
SHORT TERM...MDP
LONG TERM...DJP
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
800 PM EST SUN NOV 27 2011
.SYNOPSIS...
WEAKENING FRONT AND INCREASING MOISTURE TONIGHT INTO MONDAY...WILL
RESULT IN THICKENING CLOUDS WITH SOME LIGHT SHOWERS OR PATCHY
DRIZZLE. HOWEVER...OUR MAIN BATCH OF RAIN WILL COME FROM A LOW
PRESSURE SYSTEM MOVING THROUGH THE REGION TUESDAY AFTERNOON
THROUGH TUESDAY NIGHT. SOME SHOWERS MAY LINGER INTO WEDNESDAY.
BEHIND THE SYSTEM...TEMPERATURES WILL COOL DOWN TO NEAR NORMAL
LEVELS DURING THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
8 PM UPDATE... THE LEADING EDGE OF THE -SHRA HAVE MADE IT TO ABT
A KELZ-KPEO-KSYR-KRME LN ATTM. NEAR-TERM NWP GUIDANCE CONTINUES TO
INDICATE THAT ANY FURTHER EWD PUSH TO THE LGT PCPN OVERNIGHT WILL
BE SMALL...AND BASED ON RECENT RADAR TRENDS...WE`RE INCLINED TO GO
ALG WITH THIS THINKING. THUS...SCTD TO NUMEROUS WORDING FOR -SHRA
WILL BE INDICATED IN OUR NRN/WRN ZNS OVERNIGHT...WITH LTL IF ANY
PCPN FARTHER TO THE S AND E...SAVE FOR SOME PATCHY DRZL IN PTNS OF
THE CATSKILLS AND POCONOS TWDS 12Z.
ONLY MINOR TWEAKS WERE MADE TO TEMP/DEW PT GRIDS THROUGH 06Z.
PREV DISC... 4 PM UPDATE...TEMPERATURES TOPPED OUT ROUGHLY 13 TO 17 DEGREES
ABOVE NORMAL...BEING HELD BACK FROM GOING FURTHER ONLY BECAUSE OF
THICKENING HIGH CLOUDS. FRONT IS APPROACHING FROM THE WEST BUT
STRUGGLING...WITH MAINLY ONLY VIRGA SO FAR EXCEPT FOR EXTREME
WESTERN PA AND NY. ONE WEAK WAVE TRAVELING THROUGH THE BRISK
SOUTHWEST FLOW WILL MANAGE TO SKIM STEUBEN COUNTY AND SOME OF THE
WESTERN FINGER LAKES WITH LIGHT SHOWERS DURING THE NEXT FEW
HOURS...THE REST OF THE AREA WILL CONTINUE TO SEE THICKENING HIGH
TO MID LEVEL CLOUDS.
A BIT OF A SQUEEZE PLAY TONIGHT INTO MONDAY MORNING...AS FRONT
STALLS OUT IN OUR NORTHWESTERN ZONES WITH LIGHT SHOWERS COMING OUT
OF TOP-DOWN MOISTENING FROM UPPER LEVELS...YET ALSO SHALLOW MARINE
MOISTURE ATTEMPTS TO RIDE IN ON SOUTHERLY LOW LEVEL FLOW. RUC AND
18Z NAM HAVE BACKED OFF SOMEWHAT ON THIS IDEA HOWEVER...WITH LIGHT
SURFACE WIND VEERING TO INCLUDE SOME WESTERLY COMPONENT...WHICH IS
NOT AS FAVORABLE FOR MARINE MOISTURE TO REACH INTO THE AREA. I
HAVE LIMITED PATCHY DRIZZLE MENTION TO SOME OF THE
POCONOS/CATSKILLS REGION SUSCEPTIBLE TO UPSLOPE FLOW...LATER
TONIGHT INTO EARLY MONDAY MORNING. FARTHER NORTHWEST...NOT AS
MUCH LOW LEVEL MOISTURE...YET ENOUGH MOISTURE IN MID/HIGH LEVELS
FOR LIGHT SHOWERS. CLOUDS HANG AROUND THROUGH MONDAY
AFTERNOON...THOUGH WITH ANY SHOWERS DIMINISHING AS WEAK FRONT
BEGINS TO SLOWLY SHIFT NORTHWARD.
WITH AMOUNT OF CLOUD COVER...ESPECIALLY LATE TONIGHT THROUGH
MONDAY...WILL BE STAYING ON WARM SIDE OF GUIDANCE FOR LOWS
TONIGHT...AND COOLER THAN THE MODELS FOR HIGHS MONDAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
GOOD MODEL AGREEMENT ON BIG PICTURE FOR UPPER LOW TO PROGRESSIVELY
MOVE THROUGH THE AREA...WITH MODEL CONSENSUS GIVING US OUR MAIN
BATCH OF RAIN LATE TUESDAY INTO TUESDAY NIGHT. WHILE THERE WILL BE
AN ATLANTIC SUBTROPICAL FEED OF MOISTURE...SPEED OF SYSTEM WILL
MINIMIZE ANY THREAT FOR WATER PROBLEMS. AT THIS TIME WE ARE
EXPECTING AREAL AVERAGE OF LESS THAN AN INCH OF RAINFALL.
HOWEVER...SOME MARGINAL INSTABILITY EVIDENT AS NEGATIVELY TILTED
FRONT COMES THROUGH TUESDAY EVENING...TO THE POINT THAT LATER
SHIFTS MAY NEED TO CONSIDER ADDING MENTION OF THUNDER. WITH
DELAYED TIMING OF FRONT...TEMPERATURES LOOK TO GET QUITE WARM ON
TUESDAY.
COLD CORE OF UPPER LOW PASSES DIRECTLY OVERHEAD WEDNESDAY...AND
EXPECTING SCATTERED SHOWERS IN THE WRAP AROUND MOISTURE OF THE
COMMA HEAD. DESPITE STRONG COLD AIR ADVECTION...925-850MB
TEMPERATURES DO NOT SUPPORT SHOWERS CHANGING OVER TO SNOW DURING
THE DAY WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
PERIOD BEGINS WITH VIGOROUS STORM SYSTEM EXITING TO THE EAST, AND
HIGH PRESSURE BUILDING NORTHWARD FROM THE LOWER OHIO VALLEY.
A WEAK LOW PRESSURE CENTER AND ASSOCIATED FRONT WILL MOVE OVER
LAKE ONTARIO EARLY FRIDAY, BRINGING WITH IT A CHANCE FOR A RAIN OR
SNOW SHOWER.
A TROF WILL DIG INTO ONTARIO PROVINCE SATURDAY INTO SUNDAY, WITH
SOME JET ACTIVITY ALONG THE US/CANADIAN BORDER. THIS WILL BRING
A BETTER CHANCE FOR SNOW SHOWERS, ESPECIALLY OVER NY STATE, THIS
WEEKEND.
TEMPERATURES WILL FLUCTUATE BETWEEN SYSTEMS, BUT OVERALL WILL BE
TRENDING BACK TOWARD SEASONABLY COOL READINGS.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
A STALLED FRONTAL SYSTEM STRETCHES FROM LOWER ONTARIO, DOWN LAKE
ERIE. SHOWERS ARE MOVING NORTHEASTWARD ALONG THE FRONT, AND WILL
AFFECT OUR TERMINALS LATER TONIGHT WHEN THE FRONT PUSHES EASTWARD.
THE EASTWARD PUSH OF THE FRONT WILL NOT LAST FOR LONG, AS IT IS
FORECAST TO RETROGRADE WESTWARD OVERNIGHT. HOWEVER SOME DRIZZLE
AND SCATTERED SHOWER ACTIVITY WILL AFFECT THE BGM, SYR, ITH, ELM,
AND RME TERMINALS WELL AFTER DARK. CEILINGS WILL SLOWLY DEGRADE TO
MVFR TERRITORY LATE TONIGHT, BEFORE RISING TO A MOSTLY CLOUDY VFR
DECK TOWARD NOON MONDAY.
WE HAVE REMOVED THE POTENTIAL FOR A MARINE LAYER MAKING IT TO AVP
OVERNIGHT, AS THE LATEST NAM12 AND RUC RUNS DISAGREE WITH THE
PREVIOUS GFS INSISTENCE OF A MARINE LAYER. CURRENT UPSTREAM OBS
SHOW SIGN OF THE LAYER COMING ASHORE.
HOWEVER AVP WILL HAVE SOME MVFR TO BORDERLINE IFR RESTRICTIONS
EARLY MONDAY MORNING IN DRIZZLE AND LIGHT FOG.
OUTLOOK...
MON NGT...IFR/MVFR. PERIODS OF RAIN AND FOG.
TUE THRU THU...PATCHY MVFR IN SCT -SHRA. SCT -SHSN AND MVFR/BRIEF
IFR POSSIBLE BEGINNING WED.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MLJ/MDP
SHORT TERM...MDP
LONG TERM...DJP
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS BUFFALO NY
656 PM EST SUN NOV 27 2011
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL MOVE INTO THE REGION TONIGHT WITH A
PERIOD OF RAIN. THE RAIN WILL LINGER INTO MONDAY MORNING BEFORE
TAPERING TO WIDELY SCATTERED LIGHT SHOWERS BY AFTERNOON AS THE FRONT
WEAKENS IN PLACE. AN AREA OF LOW PRESSURE WILL THEN LIFT ACROSS THE
LOWER LAKES TUESDAY AND TUESDAY NIGHT WITH MORE RAIN...WHICH MAY END
AS A LITTLE WET SNOW ON WEDNESDAY AS COOLER AIR FILTERS INTO THE
REGION. DRY WEATHER WILL RETURN ON THURSDAY BEFORE COLDER AIR
ARRIVES FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH MONDAY/...
REGIONAL RADAR IMAGERY THIS EVENING SHOWS AN AREA OF STEADY RAIN
SHOWERS EXTENDING FROM THE SOUTHERN TIER TO THE FINGER
LAKES...CONTINUING EAST INTO THE NORTH COUNTRY. THE
LOCATION OF THE RAIN CORRELATES WELL WITH AN AREA OF ENHANCED LOW
LEVEL MOISTURE CONVERGENCE IN THE VICINITY OF THE LOW LEVEL JET THAT
IS CURRENTLY PUSHING ACROSS NEW YORK STATE. THE LATEST HRRR QPF
OUTPUT STILL SHOWS THE STEADIEST RAIN TAPERING OFF FOR AWHILE THIS
EVENING...BEFORE A SECOND SURGE OF RAIN DEVELOPS ALONG THE SLOW
MOVING COLD FRONT THAT WILL BE PUSHING INTO WESTERN NEW YORK THIS
EVENING.
MEANWHILE...A SPLIT FLOW REMAINS IN PLACE OVER THE MID SECTION OF
THE NATION...FEATURING NORTHERN STREAM ENERGY ACCELERATING EAST
ACROSS QUEBEC...WHILE THE SOUTHERN STREAM ENERGY IS LEFT BEHIND TO
EVOLVE INTO A CLOSED LOW OVER THE LOWER MISSISSIPPI VALLEY. THE
ASSOCIATED COLD FRONT WILL CONTINUE TO ADVANCE SLOWLY EASTWARD
OVERNIGHT...THEN STALL AND WASH OUT ON MONDAY AS THE LOW LEVEL FLOW
QUICKLY EVOLVES INTO A COL BETWEEN THE TWO MID LEVEL CLOSED LOWS.
PWAT OF 1-1.25 INCHES IS AVAILABLE ALONG AND AHEAD OF THIS FRONT...
WHICH IS 2-3 STANDARD DEVIATIONS ABOVE AVERAGE FOR LATE NOVEMBER.
MAIN FORCING MECHANISMS WILL BE FRONTOGENESIS AND CONVERGENCE IN THE
800-700MB LAYER ALONG THE ADVANCING FRONT...AND UPPER LEVEL
DIVERGENCE IN THE RIGHT ENTRANCE REGION OF A 140 KNOT UPPER LEVEL
JET.
WITH THE DEEP LAYER FRONTAL ASCENT AND AMPLE SUPPLY OF MOISTURE
WIDESPREAD RAIN ALONG THE FRONTAL BOUNDARY IS A CERTAINTY...THE MAIN
FORECAST CHALLENGE IS THE PLACEMENT AND TIMING WITH A SHARP EASTERN
CUTOFF TO THE STEADIER RAIN. EXPECT THE STEADIER RAIN
TO MAKE ONLY MAKE VERY SLOW PROGRESS EASTWARD TOWARDS THE GENESEE
VALLEY AND FINGER LAKES OVERNIGHT. AS FAR AS RAINFALL AMOUNTS
GO...EXPECT BASIN AVERAGE OF A QUARTER TO A THIRD OF AN INCH ACROSS
WESTERN NY AND THE NORTH COUNTRY...WITH MUCH LESS ACROSS THE FINGER
LAKES.
MONDAY MORNING EXPECT RAIN TO STILL BE QUITE WIDESPREAD ACROSS MUCH
OF THE REGION AT SUNRISE. THE STEADIER RAIN WILL QUICKLY TAPER OFF
DURING THE MORNING AS FRONTAL CONVERGENCE BREAKS DOWN DUE TO THE
LOSS OF MID LEVEL FLOW WITHIN THE DEVELOPING COL REGION. THERE WILL
BE PLENTY OF LOW CLOUDS AROUND IN THE WEAK NORTHERLY UPSLOPE FLOW
BEHIND THE WASHING OUT FRONTAL BOUNDARY...SO THIS WILL LIKELY ALLOW
LIGHT SHOWERS AND DRIZZLE TO LINGER INTO THE EARLY AFTERNOON. LATER
IN THE DAY EXPECT MUCH OF THE AREA TO BE DRY...ALTHOUGH WITH THE
LINGERING FRONTAL BOUNDARY NEARBY CANNOT RULE OUT A FEW LIGHT
SHOWERS ESPECIALLY FROM THE SOUTHERN TIER INTO THE FINGER LAKES.
WESTERN AND CENTRAL NY WILL BE ON THE COOL SIDE OF THE BOUNDARY BY
MONDAY...AND THAT COMBINED WITH PLENTY OF LOW/THICK CLOUD COVER WILL
BRING MUCH COOLER TEMPS WITH THE NORTHERN HALF OF THE AREA LIKELY
NOT MAKING IT OUT OF THE UPPER 40S...WITH SOME LOWER 50S NEAR THE
PENNSYLVANIA STATE LINE AND IN CENTRAL NY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
BY MONDAY EVENING...A DEVELOPING AREA OF LOW PRESSURE ASSOCIATED
WITH A CUT OFF 500 MB LOW WILL BE NEAR KENTUCKY. MEANWHILE...A
STALLED FRONTAL BOUNDARY WILL SIT SOMEWHERE ACROSS WESTERN NEW YORK.
ITS THIS BOUNDARY THAT SHOULD KEY ANY RAIN SHOWERS MONDAY NIGHT. AS THE
LOW LIFTS NORTHWARD...IT WILL FORCE THIS BOUNDARY NORTH AS
WELL...WITH AN INCREASING SOUTHERLY FLOW RESULTING IN WARM AIR
ADVECTION AND LIFT ALONG THIS FRONT. ON MONDAY EVENING EXPECT
SCATTERED SHOWERS ACROSS WESTERN NEW YORK TO ENHANCE AS IT LIFTS
ACROSS LAKE ERIE AND ONTARIO. WHILE MODELS DISAGREE SLIGHTLY ON THE
FRONTAL POSITION...A CONSENSUS BRINGS THE AXIS OF RAIN SHOWERS INTO
SOUTHERN ONTARIO BY DAYBREAK.
ON TUESDAY...THE LOW WILL SLOWLY LIFT INTO OHIO. AS THE SURFACE LOW
LIFTS NORTHWARD...A BROAD AREA OF RAIN WILL LIFT INTO THE REGION
FROM SOUTHWEST TO NORTHEAST. AGAIN...THERE ARE SOME MODEST TIMING
DIFFERENCES...WITH THE GFS ABOUT 6 HOURS FASTER THAN THE
NAM...HOWEVER BOTH MODELS AGREE ON THE GENERAL TREND HERE...SO CAN
JUST SPLIT THE DIFFERENCE. STEADY RAIN SHOULD MOVE IN TUESDAY
AFTERNOON AND EVENING...THEN GRADUALLY EXIT TO THE NORTH LATE
TUESDAY NIGHT.
AS THE LOW LIFTS INTO INTO QUEBEC WEDNESDAY...WINDS WILL SHIFT TO
THE SW AND TEMPERATURES WILL COOL DRAMATICALLY AT BOTH THE SURFACE
AND ALOFT. THIS WILL CAUSE LINGERING RAIN SHOWERS TO MIX WITH SNOW
ON WEDNESDAY. 850 MB TEMPS WILL BE MODESTLY COOL...AT ABOUT -3C. IT
APPEARS FOR MOST...IT WILL BE TOO WARM FOR SNOW SHOWERS TO
ACCUMULATE ON WEDNESDAY. HOWEVER...THE HIGHER TERRAIN OF THE
SOUTHERN TIER BEARS WATCHING. AS THE UPPER LOW PASSES...TEMPERATURES WILL
BE JUST COOL ENOUGH ALOFT FOR SOME MODEST LAKE ENHANCEMENT...AND
SOME UPSLOPING. THIS SAID...IT DOES NOT LOOK LIKE MUCH...PERHAPS A
WET INCH OR TWO ACROSS HIGHER TERRAIN.
WHILE THIS SYSTEM WILL LIKELY CAUSE AN AREA OF HEAVY RAINFALL IN
EXCESS OF TWO INCHES...THIS AREA WILL LIKELY BE TO OUR SOUTH AND
WEST. IT WOULD TAKE A SIGNIFICANT EASTWARD SHIFT IN THE TRACK OF THE
LOW TO CAUSE THIS AXIS TO SHIFT INTO WESTERN NEW YORK...WITH MMEFS
ENSEMBLES SHOWING ONLY A SLIGHT CHANCE OF THIS HAPPENING. IF THERE
WERE TO BE ISSUES...IT WOULD BE IN THE BUFFALO CREEKS. AT THIS
TIME...ABOUT AN INCH OF RAIN IS EXPECTED IN THE NIAGARA
FRONTIER...WITH BETWEEN A HALF INCH AND AN INCH ELSEWHERE. THIS
WOULD NOT BE ENOUGH TO CAUSE FLOODING.
GUSTY NE WINDS WILL DEVELOP ON LAKE ONTARIO AND THE NIAGARA FRONTIER
TUESDAY EVENING. WINDS WILL SHIFT TO THE SOUTHWEST LATE THAT NIGHT
AND WEDNESDAY...WITH BEST WINDS FOCUSING ON LAKE ERIE AND INTO THE
NIAGARA FRONTIER. IN EACH CASE...THE STRONGEST GUSTS LOOK TO BE IN
THE 40 MPH RANGE.
TEMPERATURES WILL CONTINUE TO BE UNSEASONABLY WARM THROUGH TUESDAY
NIGHT. WITH LITTLE DROP IN OVERNIGHT LOWS...ESPECIALLY IN THE
SOUTHERN TIER AND EAST OF LAKE ONTARIO REGIONS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
LINGERING SNOW SHOWERS EAST OF LAKE ONTARIO SHOULD TAPER OFF LATE
WEDNESDAY NIGHT. AFTER THIS...HIGH PRESSURE WILL BUILD INTO THE
REGION THROUGH THURSDAY...BRINGING FAIR WEATHER AND SEASONABLE
TEMPERATURES.
A CLIPPER LOW WILL APPROACH THURSDAY NIGHT...CROSSING THE REGION
FRIDAY. 12Z MODELS HAVE SLOWED A BIT WITH THIS SYSTEM...SO WILL
TREND BACK TIMING ACCORDINGLY. THIS WILL BRING A CHANCE OF SNOW
SHOWERS TO THE REGION FRIDAY...AND ALSO AT THE FIRST MEASURABLE
SNOW OF THE SEASON FOR BUFFALO. 850 MB TEMPS WITH THIS AREA ABOUT
-11C...SO IT SHOULD BE COLD ENOUGH TO PRODUCE LAKE ENHANCED SNOWS
WHERE WINDS ARE FAVORABLE. ITS UNLIKELY THE FAST MOVING WOULD BE
ABLE TO DROP TOO MUCH SNOW GIVEN HOW FAST ITS MOVING.
THE CLIPPER SHOULD EXIT EAST FRIDAY NIGHT...ALLOWING HIGH PRESSURE
TO ONCE AGAIN RIDGE ACROSS THE REGION. SATURDAY SHOULD BE ANOTHER
FAIR AND SEASONABLY COOL DAY.
FOR SUNDAY...THE 12Z GFS/EUROPEAN DIFFER QUITE A BIT. THE GFS DIGS A
TROF INTO THE NORTHEAST...WHICH WOULD BE FAVORABLE FOR SNOW
SHOWERS...WHILE THE EUROPEAN CONTOURS TO KEEP AN UPPER LEVEL RIDGE
ACROSS THE REGION. FOR NOW...LEAN SLIGHTLY TOWARD THE EUROPEAN...AND
KEEP ONLY SLIGHT CHANCE POPS IN FOR SUNDAY.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
THE MOIST SOUTHERLY FLOW AHEAD OF THE APPROACHING COLD FRONT IS
GENERATING LIGHT TO MODERATE RAIN SHOWERS ACROSS A GOOD PART OF THE
AREA THIS EVENING. THE SOUTHERLY DOWNSLOPING WIND IS STILL HELPING
TO MAINTAIN MAINLY VFR CONDITIONS AT MOST LOCATIONS NORTH OF THE
SOUTHERN TIER. AS THE STEADIER RAIN BECOMES MORE WIDESPREAD ALONG
THE FRONT THIS EVENING AND OVERNIGHT...THE ATMOSPHERE WILL SATURATE
EVEN MORE...CAUSING CIGS TO DETERIORATE TO MVFR...THEN IFR
AS WINDS SLOWLY VEER WITH THE APPROACH AND PASSAGE OF THE COLD
FRONT.
EXPECT THE IFR CONDITIONS TO LAST THROUGH MONDAY MORNING...BEFORE
LIFTING TO MVFR AS THE STEADIER RAIN TAPERS OFF. IFR CIGS WILL
LIKELY CONTINUE ACROSS THE SOUTHERN TIER.
LOW LEVEL WIND SHEAR WILL CONTINUE THROUGH THIS EVENING WITH A 40-50
KNOT LOW LEVEL JET OVERHEAD. THIS QUICKLY BREAKS DOWN LATER THIS
EVENING AND WILL BRING AN END TO THE WIND SHEAR.
OUTLOOK...
TUESDAY...AREAS OF MVFR/IFR WITH SHOWERS LIKELY AT TIMES.
WEDNESDAY...MVFR WITH RAIN/SNOW SHOWERS.
THURSDAY...VFR.
FRIDAY...MVFR WITH A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
MODERATE SOUTHERLY WINDS WILL CONTINUE INTO EARLY THIS EVENING
BEFORE DIMINISHING OVERNIGHT AS THE PRESSURE GRADIENT RELAXES. SMALL
CRAFT ADVISORIES WILL BE MAINTAINED THROUGH THIS EVENING ON LAKE
ERIE. LATER TONIGHT A COLD FRONT WILL MOVE SLOWLY SOUTHEAST ACROSS
THE LOWER LAKES REGION WITH WINDS VEERING WEST AND EVENTUALLY
NORTHWEST BY MONDAY MORNING. A BRIEF PERIOD OF 15 KNOT WEST WINDS
WILL OCCUR ON LAKE ONTARIO FROM LATE TONIGHT INTO MONDAY MORNING BUT
THIS WILL BE SHORT LIVED AND WINDS AND WAVES ARE EXPECTED TO REMAIN
JUST BELOW SMALL CRAFT ADVISORY CRITERIA.
LATER MONDAY INTO TUESDAY WINDS WILL DIMINISH AND EVENTUALLY BECOME
EAST TO NORTHEAST AND INCREASE AS LOW PRESSURE ORGANIZES OVER THE
OHIO VALLEY. NORTHEAST WINDS WILL INCREASE TUESDAY NIGHT ESPECIALLY
ON LAKE ONTARIO WITH SOLID SMALL CRAFT ADVISORY CONDITIONS AND AN
OUTSIDE CHANCE OF GALES. WINDS FLIP AROUND TO THE SOUTHWEST ON
WEDNESDAY AS LOW PRESSURE PULLS INTO THE SAINT LAWRENCE VALLEY WITH
ANOTHER PERIOD OF HIGH END SMALL CRAFT ADVISORY CONDITIONS ON BOTH
LAKES.
&&
.CLIMATE...
THE VERY WARM NOVEMBER CONTINUES WITH MANY AREAS ON THE LAKE
PLAINS CRACKING INTO THE LOWER 60S TODAY ON MILD SOUTHERLY WINDS.
HERE ARE SOME STATS THROUGH NOVEMBER 26TH...
AT BUFFALO...THE AVERAGE TEMPERATURE FOR THE MONTH IS 46.3 DEGREES
WHICH IS 4.7 DEGREES ABOVE AVERAGE. THIS RANKS AS THE 6TH WARMEST
ON RECORD. THERE ARE A FEW MORE WARM DAYS ON THE WAY...AND THIS
MAY ALLOW US TO COME UP A SLOT OR TWO BUT THE WARMEST NOVEMBER IS
OUT OF REACH. THERE HAS YET TO BE MEASURABLE SNOW AT THE BUFFALO
AIRPORT WITH A TRACE ON SEVERAL DAYS THIS MONTH. THE LATEST DATE
OF FIRST MEASURABLE SNOW IS DECEMBER 3RD...WITH 4 PREVIOUS YEARS
SEEING NO MEASURABLE SNOW IN THE MONTH OF NOVEMBER. ONE OF THESE
YEARS WAS JUST TWO YEARS AGO IN 2009 WHEN THE FIRST MEASURABLE
SNOW WAS ON DECEMBER 1ST. THERE IS A CHANCE OF SOME WET SNOW ON
WEDNESDAY BUT THIS MAY NOT MEASURE AS SURFACE TEMPERATURES REMAIN
ABOVE FREEZING.
AT ROCHESTER...THE AVERAGE TEMPERATURE FOR THE MONTH IS 45.5
DEGREES WHICH IS 4.2 DEGREES ABOVE AVERAGE. THIS RANKS AS THE 8TH
WARMEST ON RECORD. THERE ARE A FEW MORE WARM DAYS ON THE
WAY...AND THIS MAY ALLOW US TO COME UP A SLOT OR TWO BUT THE
WARMEST NOVEMBER IS OUT OF REACH. UNLIKE BUFFALO...THE ROCHESTER
AIRPORT RECEIVED ITS FIRST MEASURABLE SNOW ON NOVEMBER 17TH.
IT SHOULD BE NOTED THAT PAST RESEARCH SHOWS NO CORRELATION BETWEEN
A WARM FALL AND THE UPCOMING WINTER.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EST THIS EVENING FOR LEZ040-
041.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...APFFEL
LONG TERM...APFFEL
AVIATION...HITCHCOCK
MARINE...HITCHCOCK/TJP
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
613 PM EST SUN NOV 27 2011
.SYNOPSIS...
WEAKENING FRONT AND INCREASING MOISTURE TONIGHT INTO MONDAY...WILL
RESULT IN THICKENING CLOUDS WITH SOME LIGHT SHOWERS OR PATCHY
DRIZZLE. HOWEVER...OUR MAIN BATCH OF RAIN WILL COME FROM A LOW
PRESSURE SYSTEM MOVING THROUGH THE REGION TUESDAY AFTERNOON
THROUGH TUESDAY NIGHT. SOME SHOWERS MAY LINGER INTO WEDNESDAY.
BEHIND THE SYSTEM...TEMPERATURES WILL COOL DOWN TO NEAR NORMAL
LEVELS DURING THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
4 PM UPDATE...TEMPERATURES TOPPED OUT ROUGHLY 13 TO 17 DEGREES
ABOVE NORMAL...BEING HELD BACK FROM GOING FURTHER ONLY BECAUSE OF
THICKENING HIGH CLOUDS. FRONT IS APPROACHING FROM THE WEST BUT
STRUGGLING...WITH MAINLY ONLY VIRGA SO FAR EXCEPT FOR EXTREME
WESTERN PA AND NY. ONE WEAK WAVE TRAVELING THROUGH THE BRISK
SOUTHWEST FLOW WILL MANAGE TO SKIM STEUBEN COUNTY AND SOME OF THE
WESTERN FINGER LAKES WITH LIGHT SHOWERS DURING THE NEXT FEW
HOURS...THE REST OF THE AREA WILL CONTINUE TO SEE THICKENING HIGH
TO MID LEVEL CLOUDS.
A BIT OF A SQUEEZE PLAY TONIGHT INTO MONDAY MORNING...AS FRONT
STALLS OUT IN OUR NORTHWESTERN ZONES WITH LIGHT SHOWERS COMING OUT
OF TOP-DOWN MOISTENING FROM UPPER LEVELS...YET ALSO SHALLOW MARINE
MOISTURE ATTEMPTS TO RIDE IN ON SOUTHERLY LOW LEVEL FLOW. RUC AND
18Z NAM HAVE BACKED OFF SOMEWHAT ON THIS IDEA HOWEVER...WITH LIGHT
SURFACE WIND VEERING TO INCLUDE SOME WESTERLY COMPONENT...WHICH IS
NOT AS FAVORABLE FOR MARINE MOISTURE TO REACH INTO THE AREA. I
HAVE LIMITED PATCHY DRIZZLE MENTION TO SOME OF THE
POCONOS/CATSKILLS REGION SUSCEPTIBLE TO UPSLOPE FLOW...LATER
TONIGHT INTO EARLY MONDAY MORNING. FARTHER NORTHWEST...NOT AS
MUCH LOW LEVEL MOISTURE...YET ENOUGH MOISTURE IN MID/HIGH LEVELS
FOR LIGHT SHOWERS. CLOUDS HANG AROUND THROUGH MONDAY
AFTERNOON...THOUGH WITH ANY SHOWERS DIMINISHING AS WEAK FRONT
BEGINS TO SLOWLY SHIFT NORTHWARD.
WITH AMOUNT OF CLOUD COVER...ESPECIALLY LATE TONIGHT THROUGH
MONDAY...WILL BE STAYING ON WARM SIDE OF GUIDANCE FOR LOWS
TONIGHT...AND COOLER THAN THE MODELS FOR HIGHS MONDAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
GOOD MODEL AGREEMENT ON BIG PICTURE FOR UPPER LOW TO PROGRESSIVELY
MOVE THROUGH THE AREA...WITH MODEL CONSENSUS GIVING US OUR MAIN
BATCH OF RAIN LATE TUESDAY INTO TUESDAY NIGHT. WHILE THERE WILL BE
AN ATLANTIC SUBTROPICAL FEED OF MOISTURE...SPEED OF SYSTEM WILL
MINIMIZE ANY THREAT FOR WATER PROBLEMS. AT THIS TIME WE ARE
EXPECTING AREAL AVERAGE OF LESS THAN AN INCH OF RAINFALL.
HOWEVER...SOME MARGINAL INSTABILITY EVIDENT AS NEGATIVELY TILTED
FRONT COMES THROUGH TUESDAY EVENING...TO THE POINT THAT LATER
SHIFTS MAY NEED TO CONSIDER ADDING MENTION OF THUNDER. WITH
DELAYED TIMING OF FRONT...TEMPERATURES LOOK TO GET QUITE WARM ON
TUESDAY.
COLD CORE OF UPPER LOW PASSES DIRECTLY OVERHEAD WEDNESDAY...AND
EXPECTING SCATTERED SHOWERS IN THE WRAP AROUND MOISTURE OF THE
COMMA HEAD. DESPITE STRONG COLD AIR ADVECTION...925-850MB
TEMPERATURES DO NOT SUPPORT SHOWERS CHANGING OVER TO SNOW DURING
THE DAY WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
PERIOD BEGINS WITH VIGOROUS STORM SYSTEM EXITING TO THE EAST, AND
HIGH PRESSURE BUILDING NORTHWARD FROM THE LOWER OHIO VALLEY.
A WEAK LOW PRESSURE CENTER AND ASSOCIATED FRONT WILL MOVE OVER
LAKE ONTARIO EARLY FRIDAY, BRINGING WITH IT A CHANCE FOR A RAIN OR
SNOW SHOWER.
A TROF WILL DIG INTO ONTARIO PROVINCE SATURDAY INTO SUNDAY, WITH
SOME JET ACTIVITY ALONG THE US/CANADIAN BORDER. THIS WILL BRING
A BETTER CHANCE FOR SNOW SHOWERS, ESPECIALLY OVER NY STATE, THIS
WEEKEND.
TEMPERATURES WILL FLUCTUATE BETWEEN SYSTEMS, BUT OVERALL WILL BE
TRENDING BACK TOWARD SEASONABLY COOL READINGS.
&&
.AVIATION /23Z SUNDAY THROUGH FRIDAY/...
A STALLED FRONTAL SYSTEM STRETCHES FROM LOWER ONTARIO, DOWN LAKE
ERIE. SHOWERS ARE MOVING NORTHEASTWARD ALONG THE FRONT, AND WILL
AFFECT OUR TERMINALS LATER TONIGHT WHEN THE FRONT PUSHES EASTWARD.
THE EASTWARD PUSH OF THE FRONT WILL NOT LAST FOR LONG, AS IT IS
FORECAST TO RETROGRADE WESTWARD OVERNIGHT. HOWEVER SOME DRIZZLE
AND SCATTERED SHOWER ACTIVITY WILL AFFECT THE BGM, SYR, ITH, ELM,
AND RME TERMINALS WELL AFTER DARK. CEILINGS WILL SLOWLY DEGRADE TO
MVFR TERRITORY LATE TONIGHT, BEFORE RISING TO A MOSTLY CLOUDY VFR
DECK TOWARD NOON MONDAY.
WE HAVE REMOVED THE POTENTIAL FOR A MARINE LAYER MAKING IT TO AVP
OVERNIGHT, AS THE LATEST NAM12 AND RUC RUNS DISAGREE WITH THE
PREVIOUS GFS INSISTENCE OF A MARINE LAYER. CURRENT UPSTREAM OBS
SHOW SIGN OF THE LAYER COMING ASHORE.
HOWEVER AVP WILL HAVE SOME MVFR TO BORDERLINE IFR RESTRICTIONS
EARLY MONDAY MORNING IN DRIZZLE AND LIGHT FOG.
OUTLOOK...
MON NGT...IFR/MVFR. PERIODS OF RAIN AND FOG.
TUE THRU THU...PATCHY MVFR IN SCT -SHRA. SCT -SHSN AND MVFR/BRIEF
IFR POSSIBLE BEGINNING WED.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...MDP
LONG TERM...DJP
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
302 PM CST SAT NOV 26 2011
.SHORT TERM...TONIGHT THROUGH TUESDAY
PRIMARY FORECAST CHALLENGES CONCERN CLOUD TRENDS...TEMPERATURES...
PRECIPITATION AND WIND OVER THE NEXT 12 TO 18 HOURS. GFS/NAM/
ECMWF/GEM HEIGHT/PRESSURE FIELDS ARE IN GOOD AGREEMENT...BUT ALL
MODELS ARE OVERDONE ON QPF. FOR PRECIPITATION...WILL USE CURRENT
RADAR TRENDS AND RUC MODEL DATA FOR GUIDANCE.
20 UTC SURFACE OBSERVATIONS SHOW LIGHT SNOW FROM ROSEAU TO FOSSTON
TO ALEXANDRIA AND POINTS EAST. RADAR ECHOES ARE WEAK TO NON-
EXISTENT...SO ANY NEW SNOW ACCUMULATION SHOULD BE MINIMAL. THE
SURFACE LOW HAS MOVED INTO THE UPPER PENINSULA OF MI WITH AN
INVERTED TROUGH INTO SOUTHWEST ONTARIO. KEPT SOME SLIGHT CHANCE
POPS OR FLURRIES ACROSS THE FAR EASTERN FORECAST AREA THIS EVENING
AND OVERNIGHT...BUT ALL AREAS SHOULD DRY OUT BY 12 UTC SUNDAY
MORNING.
OVERCAST SKIES HAVE PLAGUED THE FORECAST AREA ALL DAY WITH THE
CLEARING LINE NOW FROM RUGBY TO ABERDEEN. IT IS THESE CLOUDS THAT
HAVE LIKELY LIMITED BOUNDARY LAYER MIXING AND HIGHER WIND SPEEDS
THIS AFTERNOON. A FEW SPOTS FROM COOPERSTOWN TO VALLEY CITY HAVE
BRIEFLY TOUCHED WIND ADVISORY CRITERIA THIS AFTERNOON. FOR NOW...
WILL LEAVE ADVISORY IN PLACE AS SOME CLEARING WEST OF THE VALLEY
BEFORE SUNSET SHOULD ENCOURAGE 35 KT WINDS NEAR 2000 FT TO MIX TO
THE SURFACE.
TEMPERATURES TONIGHT WILL BE HIGHLY DEPENDENT ON CLOUD COVER. WITH
CLEARING SKIES ALONG AND WEST OF THE VALLEY FOR MUCH OF THE NIGHT
AND CURRENT DEW POINT TEMPERATURES ACROSS CENTRAL ND IN THE SINGLE
DIGITS TO TEENS ABOVE ZERO...EXPECT LOWS TO DIP DOWN INTO THE LOW
TEENS TONIGHT ACROSS EASTERN ND. DEPENDING ON THE FULL EXTENT OF
NEAR SURFACE DRYING THAT TAKES PLACE...TEMPERATURES MAY DROP EVEN
FURTHER. TO THE EAST WHERE CLOUD COVER WILL BE SLOWER TO ERODE...
UPPER TEENS TO LOW 20S SEEM REASONABLE AT THIS TIME.
SUNDAY WILL BE DRY AND SLIGHTLY WARMER AS SURFACE HIGH PRESSURE
NOSES INTO THE NORTHERN PLAINS. A DRY COLD FRONT WILL DROP SOUTH
ACROSS THE FORECAST AREA MONDAY AFTERNOON...BUT TEMPERATURES IN
THE 925 TO 850 HPA LAYER FROM +2 TO +8 C AHEAD OF THE FRONT SHOULD
ALLOW HIGHS TO CLIMB INTO THE MID 30S TO LOWER 40S. SURFACE HIGH
PRESSURE RE-ESTABLISHES ITSELF ON TUESDAY...BUT FULL EXTENT OF
COOLING AFTER FRONTAL PASSAGE WILL TAKE AFFECT WITH HIGHS ONLY IN
THE LOWER TO MID 30S.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
MODELS INITIALIZED WELL THIS RUN AND REMAIN IN RELATIVELY GOOD
AGREEMENT...SO WENT WITH A BLENDED SOLN ATTM. BROAD UPPER RIDGE IS
IN PLACE EARLY IN THE PERIOD SO LOOKING AT SLIGHTLY ABOVE NORMAL
TEMPS AND LITTLE PCPN. A VIGOROUS SHORT WAVE IS EXPECTED TO CROSS
THE AREA LATE WED BRINGING A COLD FRONT...SLIGHTLY COOLER
TEMPS...AND A SLIGHT CHANCE FOR MEASURABLE PCPN. OTHERWISE...THE
UPPER RIDGE QUICKLY REBOUNDS...AND RETURN FLOW AT THE SURFACE WILL
BRING A RETURN TO A BIT WARMER TEMPS BY THE END OF THE PERIOD.
&&
.AVIATION...
VFR CIGS ARE WORKING THEIR WAY ACROSS THE DEVILS LAKE BASIN. OTHER
TAF SITES REMAIN MVFR OR IFR. AS SURFACE LOW PRESSURE CONTINUES TO
MOVE EAST ACROSS THE GREAT LAKES...A SFC RIDGE AND RETURN FLOW WILL
HELP DRY OUT THE BOUNDARY LAYER. CLEARING SHOULD SPREAD FROM WEST TO
EAST OVERNIGHT AND IS REFLECTED IN THE TAFS...WITH THE LAST SITES
SCATTERING OUT BY 09Z.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ006-007-014-015-
024-026-028-029-038-039-049-052>054.
MN...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ003-029-040.
&&
$$
ROGERS/HOPKINS
AREA FORECAST DISCUSSION
NWS NORMAN OK
1047 PM CST FRI NOV 25 2011
.AVIATION...
/06Z TAFS/
SCATTERED SHOWERS WILL CONTINUE TO AFFECT MUCH OF THE AREA
OVERNIGHT AS AN UPPER LEVEL STORM SYSTEM MOVES EAST ACROSS THE
PLAINS. CEILINGS WILL LOWER AT TIMES BELOW MVFR THRESHOLDS.
MEANWHILE... A COLD FRONT WILL MOVE INTO NW OK LATE TONIGHT AND
ACROSS REMAINING TERMINAL LOCATIONS BY SATURDAY MORNING. ALTHOUGH
THE RAIN WILL BE SHIFTING EAST OUT OF THE AREA AND CEILINGS
GRADUALLY IMPROVING DURING THE DAY... STRONG SURFACE WINDS...
WITH GUSTS IN EXCESS OF 35 KTS... WILL CONTINUE BEHIND THE FRONT
THROUGH MUCH OF THE FORECAST PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1012 PM CST FRI NOV 25 2011/
UPDATE...
FIRST BAND OF PRECIPITATION CONTINUES TO SHIFT EAST AS THE AREAS
OF RAIN THEMSELVES MOVE NORTHEAST. ADDITIONAL SHOWER AND
THUNDERSTORM DEVELOPMENT CONTINUES IN WESTERN KANSAS AND THE
OKLAHOMA AND NORTHERN TEXAS PANHANDLES NEAR THE SURFACE FRONT.
LOCAL WRF.. HRRR AND RUC SUGGEST THAT THERE WILL BE THE CHANCE OF
DEVELOPMENT DOWN THE FRONT AS IT MOVES SOUTHEAST. HAVE UPDATED THE
POPS TO ACCOUNT FOR THE CURRENT POSITION AND MOVEMENTS OF THE
FIRST BAND... AND THE POTENTIAL FOR REDEVELOPMENT SOUTHWEST ALONG
THE FRONT OVERNIGHT. HAVE ALSO MADE SOME ADJUSTMENTS TO THE HOURLY
TEMPERATURE GRIDS AS TEMPERATURES WILL BE SLOW TO COOL AHEAD OF
THE FRONT WITH THE WIDESPREAD CLOUD COVER. DID NOT ADJUST THE MINS
AT THIS TIME... ALTHOUGH THERE WILL BE THE POTENTIAL FOR SOME
ADJUSTMENTS LATER DEPENDING ON THE TIMING OF THE FRONT OVERNIGHT.
WE UPDATED THE WIND ADVISORY EARLIER THIS EVENING TO INCLUDE THE
SOUTHERN THREE OF OUR TEXAS COUNTIES TO BRIDGE THE GAP WITH
NEIGHBORS AND AS WINDS TOMORROW LOOK TO BE AROUND THE SAME AS
ADJACENT AREAS THAT WERE IN THE ADVISORY.
PREV DISCUSSION... /ISSUED 558 PM CST FRI NOV 25 2011/
AVIATION...
/00Z TAFS/
WIDESPREAD AREAS OF RAIN WILL SPREAD FROM WEST TO EAST ACROSS THE
AREA OVERNIGHT AS AN UPPER LEVEL STORM SYSTEM MOVES THROUGH THE
PLAINS. FREQUENT MVFR CEILINGS ARE EXPECTED THROUGH MUCH OF THE
NIGHT. A COLD FRONT WILL MOVE INTO NW OK LATE TONIGHT AND ACROSS
REMAINING TERMINAL LOCATIONS BY SATURDAY MORNING. ALTHOUGH THE
RAIN WILL BE SHIFTING EAST OUT OF THE AREA AND CEILINGS GRADUALLY
IMPROVING IN THE MORNING... STRONG SURFACE WINDS... WITH GUSTS IN
EXCESS OF 30 KTS... WILL PREVAIL BEHIND THE FRONT THROUGH THE DAY.
PREV DISCUSSION... /ISSUED 253 PM CST FRI NOV 25 2011/
DISCUSSION...RAIN TONIGHT...WINDY AND COLDER SATURDAY...AND LOOKING
AT MODEL DIFFERENCES WITH RELATIVELY LOW IMPACT BEYOND SATURDAY.
LOW LEVEL MOISTURE REMAINS TRAPPED BENEATH AN INVERSION...GIVING US
DULL OVERCAST THROUGH THIS EVENING. MEANWHILE...RAIN WILL DEVELOP
FROM A MID LEVEL CLOUD DECK AS BROAD AND NEARLY UNIFORM HEIGHT FALLS
OVERSPREAD OUR REGION IN ADVANCE OF AN UPPER LEVEL TROUGH. THIS WAVE
OF HEIGHT FALLS WILL BRING A WIDE BAND OF LIGHT RAIN EASTWARD DURING
THE EVENING. THE LOWER LEVELS START TO PARTICIPATE IN THE LIFTING
LATER TONIGHT WHEN A RELATIVELY STRONG FRONT OFF THE NORTHERN
PACIFIC DIVES IN FROM THE NORTHWEST. FORECAST SOUNDINGS BECOME
DEEPLY SATURATED BEHIND THE FRONT...AND WE SHOULD SEE A SWATH OF
SOMEWHAT HEAVIER RAINFALL TRANSLATE FROM NORTHWEST TO SOUTHEAST
DURING THE EARLY MORNING HOURS SATURDAY. SOME EMBEDDED THUNDER IS
POSSIBLE.
WINDS WILL BECOME STRONG AND GUSTY BEHIND THE FRONT...BUT WILL BE
ESPECIALLY STRONG AFTER SUNRISE TO THE WEST OF THE CLEARING LINE.
SINCE CLOUDS ARE FORECAST TO LINGER IN SOUTHEAST OKLAHOMA...WE DID
NOT ADD THE REMAINING COUNTIES TO OUR WIND ADVISORY...BUT COLD
ADVECTION WILL BE MAXIMIZED IN THOSE COUNTIES DURING THE DAY...SO
ANY ANTICIPATION OF CLEARING SKIES AND DEEPER MIXING WOULD SIGNAL
THE NEED TO EXPAND THE ADVISORY. LOOKS LIKE A SOLID ADVISORY
ELSEWHERE WITH SPEEDS SUSTAINED OVER 30 AT TIMES...GUSTING 45-50 MPH.
THE WIND WILL MAKE IT FEEL VERY COOL COMPARED TO RECENT DAYS. WITH A
MODEL CONSENSUS OF 850 MB TEMPS BELOW ZERO...WE LOWERED SURFACE
TEMPS TO THE 40S AND LOW 50S SATURDAY. WIND CHILL DIP TO THE TEENS
SUNDAY MORNING.
THE REMAINDER OF THE FORECAST LOOKS DRY...BUT NOT EASY BY ANY MEANS.
IN WATCHING THE RUN TO RUN VOLATILITY OF THE MODELS...IT APPEARS THE
SYNOPTIC PATTERN IS IN A LESS PREDICTABLE STATE RIGHT NOW. THE ECMWF
SOLUTION MAKES SOME SENSE...IN STRETCHING AND DEEPENING THE CURRENT
UPPER TROUGH WHILE IT GETS SQUEEZED BETWEEN TWO AMPLIFYING RIDGES.
THE DEGREE TO WHICH THE ECMWF CLOSES OFF AND DEEPENS MAY BE
OVERDONE...BUT IT APPEARS MORE REASONABLE THAN THE EXTREMELY
PROGRESSIVE GFS/NAM. WE DID NOTE THAT FINALLY THIS MORNING SEVERAL
OF THE GFS ENSEMBLE MEMBERS MOVED OVER TO SUPPORT THE ECMWF
SOLUTION...LEAVING THE OPERATIONAL GFS AT THE VERY FAR PROGRESSIVE
END OF THE ENVELOPE.
AFTER ALL THAT FUN DISCUSSION...THE DIFFERENCES DO NOT REALLY MEAN
MUCH FOR US...OTHER THAN A FEW DEGREES COOLER TEMPERATURE ON SUNDAY
AND MONDAY...AND SOME POTENTIAL FOR WRAPAROUND MID CLOUDS IN EASTERN
OKLAHOMA. THE MODELS MOVE BACK INTO BETTER AGREEMENT BY MID
WEEK...AND PREDICT A SPLIT FLOW PATTERN THAT IS BECOMING MORE
PRONOUNCED. THE NORTHERN STREAM IS SET TO DUMP A DECENTLY COLD AIR
MASS HERE BY LATE NEXT WEEK...WHILE ANOTHER CLOSED LOW FORMS IN THE
SOUTHERN STREAM OVER CALIFORNIA. INTERPOLATING FORWARD...WE COULD
HAVE OUR FIRST RUN-IN WITH WINTER PRECIPITATION TYPES BY NEXT
WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 43 49 27 49 / 80 30 0 0
HOBART OK 41 50 25 54 / 50 10 0 0
WICHITA FALLS TX 48 54 29 55 / 70 20 0 0
GAGE OK 37 48 21 54 / 50 0 0 0
PONCA CITY OK 42 49 28 47 / 100 20 0 0
DURANT OK 55 59 32 51 / 80 60 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY FROM 7 AM TO 8 PM CST SATURDAY FOR OKZ004>042-
044>046-050.
TX...WIND ADVISORY FROM 7 AM TO 8 PM CST SATURDAY FOR TXZ083>090.
&&
$$
26/25/32
AREA FORECAST DISCUSSION
NWS NORMAN OK
1012 PM CST FRI NOV 25 2011
.UPDATE...
FIRST BAND OF PRECIPITATION CONTINUES TO SHIFT EAST AS THE AREAS
OF RAIN THEMSELVES MOVE NORTHEAST. ADDITIONAL SHOWER AND
THUNDERSTORM DEVELOPMENT CONTINUES IN WESTERN KANSAS AND THE
OKLAHOMA AND NORTHERN TEXAS PANHANDLES NEAR THE SURFACE FRONT.
LOCAL WRF.. HRRR AND RUC SUGGEST THAT THERE WILL BE THE CHANCE OF
DEVELOPMENT DOWN THE FRONT AS IT MOVES SOUTHEAST. HAVE UPDATED THE
POPS TO ACCOUNT FOR THE CURRENT POSITION AND MOVEMENTS OF THE
FIRST BAND... AND THE POTENTIAL FOR REDEVELOPMENT SOUTHWEST ALONG
THE FRONT OVERNIGHT. HAVE ALSO MADE SOME ADJUSTMENTS TO THE HOURLY
TEMPERATURE GRIDS AS TEMPERATURES WILL BE SLOW TO COOL AHEAD OF
THE FRONT WITH THE WIDESPREAD CLOUD COVER. DID NOT ADJUST THE MINS
AT THIS TIME... ALTHOUGH THERE WILL BE THE POTENTIAL FOR SOME
ADJUSTMENTS LATER DEPENDING ON THE TIMING OF THE FRONT OVERNIGHT.
WE UPDATED THE WIND ADVISORY EARLIER THIS EVENING TO INCLUDE THE
SOUTHERN THREE OF OUR TEXAS COUNTIES TO BRIDGE THE GAP WITH
NEIGHBORS AND AS WINDS TOMORROW LOOK TO BE AROUND THE SAME AS
ADJACENT AREAS THAT WERE IN THE ADVISORY.
&&
.PREV DISCUSSION... /ISSUED 558 PM CST FRI NOV 25 2011/
AVIATION...
/00Z TAFS/
WIDESPREAD AREAS OF RAIN WILL SPREAD FROM WEST TO EAST ACROSS THE
AREA OVERNIGHT AS AN UPPER LEVEL STORM SYSTEM MOVES THROUGH THE
PLAINS. FREQUENT MVFR CEILINGS ARE EXPECTED THROUGH MUCH OF THE
NIGHT. A COLD FRONT WILL MOVE INTO NW OK LATE TONIGHT AND ACROSS
REMAINING TERMINAL LOCATIONS BY SATURDAY MORNING. ALTHOUGH THE
RAIN WILL BE SHIFTING EAST OUT OF THE AREA AND CEILINGS GRADUALLY
IMPROVING IN THE MORNING... STRONG SURFACE WINDS... WITH GUSTS IN
EXCESS OF 30 KTS... WILL PREVAIL BEHIND THE FRONT THROUGH THE DAY.
PREV DISCUSSION... /ISSUED 253 PM CST FRI NOV 25 2011/
DISCUSSION...RAIN TONIGHT...WINDY AND COLDER SATURDAY...AND LOOKING
AT MODEL DIFFERENCES WITH RELATIVELY LOW IMPACT BEYOND SATURDAY.
LOW LEVEL MOISTURE REMAINS TRAPPED BENEATH AN INVERSION...GIVING US
DULL OVERCAST THROUGH THIS EVENING. MEANWHILE...RAIN WILL DEVELOP
FROM A MID LEVEL CLOUD DECK AS BROAD AND NEARLY UNIFORM HEIGHT FALLS
OVERSPREAD OUR REGION IN ADVANCE OF AN UPPER LEVEL TROUGH. THIS WAVE
OF HEIGHT FALLS WILL BRING A WIDE BAND OF LIGHT RAIN EASTWARD DURING
THE EVENING. THE LOWER LEVELS START TO PARTICIPATE IN THE LIFTING
LATER TONIGHT WHEN A RELATIVELY STRONG FRONT OFF THE NORTHERN
PACIFIC DIVES IN FROM THE NORTHWEST. FORECAST SOUNDINGS BECOME
DEEPLY SATURATED BEHIND THE FRONT...AND WE SHOULD SEE A SWATH OF
SOMEWHAT HEAVIER RAINFALL TRANSLATE FROM NORTHWEST TO SOUTHEAST
DURING THE EARLY MORNING HOURS SATURDAY. SOME EMBEDDED THUNDER IS
POSSIBLE.
WINDS WILL BECOME STRONG AND GUSTY BEHIND THE FRONT...BUT WILL BE
ESPECIALLY STRONG AFTER SUNRISE TO THE WEST OF THE CLEARING LINE.
SINCE CLOUDS ARE FORECAST TO LINGER IN SOUTHEAST OKLAHOMA...WE DID
NOT ADD THE REMAINING COUNTIES TO OUR WIND ADVISORY...BUT COLD
ADVECTION WILL BE MAXIMIZED IN THOSE COUNTIES DURING THE DAY...SO
ANY ANTICIPATION OF CLEARING SKIES AND DEEPER MIXING WOULD SIGNAL
THE NEED TO EXPAND THE ADVISORY. LOOKS LIKE A SOLID ADVISORY
ELSEWHERE WITH SPEEDS SUSTAINED OVER 30 AT TIMES...GUSTING 45-50 MPH.
THE WIND WILL MAKE IT FEEL VERY COOL COMPARED TO RECENT DAYS. WITH A
MODEL CONSENSUS OF 850 MB TEMPS BELOW ZERO...WE LOWERED SURFACE
TEMPS TO THE 40S AND LOW 50S SATURDAY. WIND CHILL DIP TO THE TEENS
SUNDAY MORNING.
THE REMAINDER OF THE FORECAST LOOKS DRY...BUT NOT EASY BY ANY MEANS.
IN WATCHING THE RUN TO RUN VOLATILITY OF THE MODELS...IT APPEARS THE
SYNOPTIC PATTERN IS IN A LESS PREDICTABLE STATE RIGHT NOW. THE ECMWF
SOLUTION MAKES SOME SENSE...IN STRETCHING AND DEEPENING THE CURRENT
UPPER TROUGH WHILE IT GETS SQUEEZED BETWEEN TWO AMPLIFYING RIDGES.
THE DEGREE TO WHICH THE ECMWF CLOSES OFF AND DEEPENS MAY BE
OVERDONE...BUT IT APPEARS MORE REASONABLE THAN THE EXTREMELY
PROGRESSIVE GFS/NAM. WE DID NOTE THAT FINALLY THIS MORNING SEVERAL
OF THE GFS ENSEMBLE MEMBERS MOVED OVER TO SUPPORT THE ECMWF
SOLUTION...LEAVING THE OPERATIONAL GFS AT THE VERY FAR PROGRESSIVE
END OF THE ENVELOPE.
AFTER ALL THAT FUN DISCUSSION...THE DIFFERENCES DO NOT REALLY MEAN
MUCH FOR US...OTHER THAN A FEW DEGREES COOLER TEMPERATURE ON SUNDAY
AND MONDAY...AND SOME POTENTIAL FOR WRAPAROUND MID CLOUDS IN EASTERN
OKLAHOMA. THE MODELS MOVE BACK INTO BETTER AGREEMENT BY MID
WEEK...AND PREDICT A SPLIT FLOW PATTERN THAT IS BECOMING MORE
PRONOUNCED. THE NORTHERN STREAM IS SET TO DUMP A DECENTLY COLD AIR
MASS HERE BY LATE NEXT WEEK...WHILE ANOTHER CLOSED LOW FORMS IN THE
SOUTHERN STREAM OVER CALIFORNIA. INTERPOLATING FORWARD...WE COULD
HAVE OUR FIRST RUN-IN WITH WINTER PRECIPITATION TYPES BY NEXT
WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 43 49 27 49 / 80 30 0 0
HOBART OK 41 50 25 54 / 50 10 0 0
WICHITA FALLS TX 48 54 29 55 / 70 20 0 0
GAGE OK 37 48 21 54 / 50 0 0 0
PONCA CITY OK 42 49 28 47 / 100 20 0 0
DURANT OK 55 59 32 51 / 80 60 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY FROM 7 AM TO 8 PM CST SATURDAY FOR OKZ004>042-
044>046-050.
TX...WIND ADVISORY FROM 7 AM TO 8 PM CST SATURDAY FOR TXZ083>090.
&&
$$
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1148 AM CST SAT NOV 26 2011
.DISCUSSION...UPDATED FOR 18Z AVIATION.
&&
.AVIATION...PRE FRONTAL TROUGH HAS PUSHED THROUGH ALL TAF
SITES...SHIFTING WIND TO THE NORTHWEST. MAIN COLD FRONT IS
TRAILING BEHIND AND WILL PUSH THROUGH THIS AFTERNOON. WINDS WILL
INCREASE BEHIND THE FRONT...GUSTING TO AROUND 30KTS. SHOWERS AND
OCCASIONAL THUNDERSTORMS WILL CONTINUE FOR VCT AND CRP. GENERALLY
MVFR CIGS EXPECTED FOR EASTERN SITES...AND VFR WEST. GUSTY WINDS
CONTINUE OVERNIGHT...AND INCREASE ONCE AGAIN TOMORROW.
&&
.PREV DISCUSSION... /ISSUED 1005 AM CST SAT NOV 26 2011/
DISCUSSION...COLD FRONT IS PROGRESSING THROUGH WEST AND CENTRAL
TEXAS THIS MORNING. WIND SHIFT HAS PUSHED INTO THE CWA BUT FEEL
THIS IS WITH A PRE FRONTAL TROUGH. WITH JUST SLIGHT DPT DROP AND
WINDS REMAIN LIGHT. REAL FRONTAL BOUNDARY A LITTLE TOUGH TO PICK
OUT...BUT SEEMS TO BE JUST THROUGH DALLAS...TO FREDERICKSBURG...TO
DEL RIO. PRECIPITATION ASSOCIATED WITH THE FRONT SO FAR HAS BEEN
RATHER LIMITED IN THE EAST...WITH ISOLATED TO AT TIMES SCATTERED
LIGHT SHOWERS IN THE WEST. LATEST RUC MODEL KEEPS THE BULK OF THE
PRECIP JUST INTO THE NORTHERN PARTS OF THE CWA. HRRR MODEL HOWEVER
SHOWS SCATTERED CONVECTION DEVELOPING ACROSS ENTIRE AREA. BOTH
MODELS INDICATE INCREASING COVERAGE OF MORE STRATIFORM PRECIP
RIGHT ALONG THE FRONT AS IT NEARS THE COAST...WHERE THE DEEPEST
MOISTURE EXISTS...12Z CRP SOUNDING HAD 1.6 PWAT. HAVE ADJUSTED
MORNING POPS SOME TO ACCOUNT FOR LACK OF CONVECTION...HOWEVER
STILL THINK WE SHOULD SEE SOME DEVELOPMENT AS TEMPS INCREASE. HAVE
ALSO ADJUSTED TEMPS TO ACCOUNT FOR WARMER TEMPS FAR EAST WHERE
CLOUDS REMAIN BROKEN AND TEMPS ALREADY APPROACHING 80 DEGREES.
PREV DISCUSSION... /ISSUED 538 AM CST SAT NOV 26 2011/
DISCUSSION...SEE AVIATION SECTION BELOW.
AVIATION...CURRENTLY VFR CIGS/VSBYS ARE ACROSS S TX...HOWEVER SCT
TO NUM SHRA`S/TSRA`S ARE EXPECTED AHD AND ALONG A STRONG COLD
FRONT LATER THIS MORNING INTO THE EARLY AFTERNOON. BEST CHC OF
TSRA`S WILL BE ACROSS VCT AREA WITH LESSER CHCS FARTHER S AND W.
AREAS BEING EFFECTED BY CONVECTION WILL LIKELY LOWER TO MVFR AND
POSSIBLY IFR LEVELS AT TIMES. AS THE COLD FRONT MOVES THROUGH S
TX...CONDITIONS WILL IMPROVE TO VFR AND WINDS WILL SHIFT TO THE N AND
INCREASE TO 20 TO 30 KNOTS WITH GUSTS UP TO AROUND 40
KNOTS...MAINLY FROM LRD TO ALI TO CRP. WENT WITH GUSTS TO AROUND
30-33KT IN THE TAFS AS THIS WILL BE MORE COMMON. NLY WINDS WILL
DECREASE OVRNIGHT BUT RESTRENGTHEN ON SUNDAY.
PREV DISCUSSION... /ISSUED 459 AM CST SAT NOV 26 2011/
SHORT TERM (TODAY THROUGH SUNDAY)...A LONG WAVE TROF DRAPED ACROSS
THE TX PANHANDLE SOUTHWARD INTO MEX WILL MOVE ACROSS THE REGION
TODAY BRINGING WITH IT A STRONG COLD FRONT. AHD OF THE COLD
FRONT...DEEP MOISTURE WILL COMBINE WITH UPPER JET...EMBEDDED SHORT
WAVE...LG OMEGA...AND DECENT LOW LEVEL CONVERGENCE TO PRODUCE
SCT/NUM SHRA`S/TSRA`S. THE ACTIVITY IS EXPECTED TO INCREASE IN
COVERAGE AS IT MOVES E TOWARD THE COAST DUE TO LOW TO MOD CAPE ALONG
THE COAST AND OVER THE GULF WATERS. THE CAPE AND THE LI`S ARE NOT
IMPRESSIVE AND THERE WILL BE LITTLE TO NO SHEAR...THEREFORE AM NOT
EXPECTING ANY ORGANIZED SVR STORMS. SOME STORMS COULD BECOME STRONG
WITH GUSTS TO AROUND 40KT AND SMALL HAIL. THE BEST CHC FOR PRECIP
WILL BE ACROSS THE NW CWA THRU MID MORNING THEN MOVG E WITH INCREASING
CHCS ACROSS THE E AND NE CWA BY AROUND NOON INTO EARLY AFTERNOON.
THE SYSTEM WILL THEN EXIT THE AREA THRU LATE AFTERNOON.
THE MAIN ISSUE BEHIND THE COLD FRONT WILL BE WINDS. THE MODELS SHOW
40KT OFF THE DECK ALONG WITH DECENT LAPSE RATES THIS AFTERNOON INTO
TONIGHT...ESPECIALLY ACROSS THE SRN CWA AND ALONG THE COASTAL
COUNTIES. THEREFORE WENT WITH A WIND ADVISORY FOR THOSE AREAS WHERE
GUSTS TO 40 MPH WILL BE MOST FREQUENT. IT WILL BE WINDY ACROSS THE
NRN CWA AS WELL...BUT SHOULD REMAIN BELOW ADVISORY LEVELS. WINDS
RELAX SOMEWHAT OVERNIGHT BUT THEN RESTRENGTHEN ON SUNDAY BUT THE WINDS
SHOULD REMAIN BELOW ADVISORY LEVELS.
WITH ONGOING CAA INTO TONIGHT...MN TEMPS ARE EXPECTED TO DIP INTO
THE MID 30S ACROSS THE NW CWA TO MID 40S ALONG THE COAST. THE
OVERNIGHT WINDS WILL REMAIN ELEVATED AND NOT ALLOW THE TEMPS TO DROP
MUCH MORE THAN THAT. DESPITE SUNNY SKIES...HIGHS ON SUNDAY WILL BE
MUCH COOLER WITH AREA WIDE 60S.
MARINE...SCT TO NUM SHRA`S/TSRA`S CAN BE EXPECTED TODAY AHD AND
ALONG A STRONG COLD FRONT THAT WILL MOVE ACROSS THE BAYS AND COASTAL
WATERS THIS AFTERNOON. WINDS WILL SHIFT TO THE N AND RAPIDLY
INCREASE TO ADVISORY LEVELS ACROSS THE BAYS AND GALE FORCE ACROSS
THE COASTAL WATERS. A GALE WARNING IS IN EFFECT FOR THE GULF WATERS
AND AN SCA IS IN EFFECT FOR THE BAYS. THE GALE FORCE WINDS ARE
EXPECTED TO DECREASE BY SUN MORNING BUT REMAIN HIGH END SCA THROUGH
SUNDAY NIGHT.
FIRE WEATHER...A COLD FRONT IS EXPECTED TO PUSH ACROSS S TX LATE
TODAY WITH STRENGTHENING N WINDS DVLPG IN ITS WAKE. ALTHOUGH DRIER
AIR WILL BE FILTERING INTO S TX...RH VALUES ARE EXPECTED TO REMAIN
ABV CRITICAL THRESHOLDS THROUGH TODAY AND TONIGHT. THEREFORE AM NOT
EXPECTING FIRE WEATHER CONDITIONS THRU TONIGHT. HOWEVER...MUCH LOWER
RH VALUES IN THE TEENS WILL BE IN PLACE ON SUNDAY AND WINDS WILL BE
BREEZY TO WINDY LEADING TO CRITICAL FIRE DANGER CONDITIONS. A FIRE
WEATHER WATCH IS IN EFFECT FOR SUNDAY.
LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...COLD DRY AIRMASS WILL
REMAIN OVER SOUTH TEXAS SUNDAY NIGHT WITH WINDS RELAXING. WENT CLOSE
TO THE COLDER MET GUIDANCE FOR MINIMUMS WITH BELOW FREEZING TEMPS
EXPECTED FOR THE INLAND COASTAL PLAINS UP INTO THE NORTHERN BRUSH
COUNTRY. WENT AHEAD AND ISSUED A FREEZE WATCH FOR THESE AREAS FOR
LATE SUNDAY NIGHT. THE ANOMALOUS DEEP UPPER LOW WILL MOVE ACROSS THE
SOUTHEAST UNITED STATES MONDAY AND TUESDAY. THE OFFSHORE FLOW WILL
WEAKEN MONDAY BUT INCREASE AGAIN ON TUESDAY. HIGH PRESSURE WILL
SURGE DOWN THE PLAINS AFTER A NORTHERN STREAM SHORT WAVE TROUGH
MOVES INTO THE UPPER MIDWEST TUESDAY WITH AN INCREASE IN WINDS
EXPECTED TUESDAY AFTERNOON. TEMPERATURES WILL ALMOST BE BACK TO
NORMAL MONDAY/TUESDAY BUT WILL FALL BACK TO BELOW NORMAL FOR
WEDNESDAY. A BRIEF WARM UP IS EXPECTED FOR THURSDAY. MEDIUM RANGE
MODELS SHOW ENERGY DIVING OUT OF THE GULF OF ALASKA INTO THE PACIFIC
NORTHWEST WEDNESDAY BUT THE MODELS DIVERGE FROM THERE ON EVOLUTION
OF THE UPPER LOW BECOMING CUTOFF FROM THE NORTHERN STREAM AND MOVING
INTO THE DESERT SOUTHWEST BY FRIDAY. POLAR AIRMASS IS EXPECTED TO
MOVE DOWN THROUGH THE PLAINS INTO SOUTH TEXAS ON FRIDAY. INCREASING
ISENTROPIC LIFT SHOULD LEAD TO AN INCREASED CLOUD COVER. 00Z GFS
GENERATED TOO MUCH PRECIP WITH THE UPPER SYSTEM EXPECTED TO BE WELL
TO THE WEST. KEPT POPS AT 10 PERCENT FOR NOW FOR FRIDAY BUT SHOWED
TEMPERATURES 5 TO 10 DEGREES BELOW NORMAL WITH WINDS INCREASING FROM
THE NORTHEAST. FIRE WEATHER CONCERNS WILL PERSIST FROM MONDAY AND
TUESDAY DUE TO A VERY DRY AIRMASS AND MODEST NORTHWEST WINDS MONDAY
AND GUSTY NORTH WINDS TUESDAY. AN ELEVATED FIRE DANGER RISK IS
EXPECTED FOR BOTH DAYS.
89/TMT
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 81 46 64 33 71 / 50 10 0 0 0
VICTORIA 75 39 61 29 67 / 70 10 0 0 0
LAREDO 76 42 65 36 75 / 30 10 0 0 0
ALICE 75 43 64 32 73 / 40 10 0 0 0
ROCKPORT 79 49 62 40 67 / 60 10 0 0 0
COTULLA 71 36 63 30 73 / 30 10 0 0 0
KINGSVILLE 81 45 64 30 73 / 50 10 0 0 0
NAVY CORPUS 80 51 63 42 68 / 50 10 0 0 0
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...FREEZE WATCH LATE SUNDAY NIGHT FOR THE FOLLOWING ZONES: BEE...
CALHOUN...GOLIAD...JIM WELLS...KLEBERG...LA SALLE...LIVE
OAK...MCMULLEN...NUECES...REFUGIO...SAN PATRICIO...VICTORIA.
FIRE WEATHER WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
FOR THE FOLLOWING ZONES: ARANSAS...BEE...CALHOUN...DUVAL...
GOLIAD...JIM WELLS...KLEBERG...LA SALLE...LIVE OAK...
MCMULLEN...NUECES...REFUGIO...SAN PATRICIO...VICTORIA...
WEBB.
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR THE FOLLOWING
ZONES: ARANSAS...CALHOUN...DUVAL...JIM WELLS...KLEBERG...
NUECES...REFUGIO...SAN PATRICIO...WEBB.
GM...GALE WARNING FROM 6 PM THIS EVENING TO 6 AM CST SUNDAY FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY
TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS
TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM CST SUNDAY
FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY
TO PORT ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO
PORT O`CONNOR.
&&
$$
PZ/83...SHORT TERM/AVIATION
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1145 AM CST SAT NOV 26 2011
.AVIATION...
WINDS WILL BE THE CONCERN OF THE DAY AT BOTH TERMINALS WITH GUSTS
APPROACHING 50KTS. WE WILL SEE LOW LEVEL BLOWING DUST MOST
PREDOMINANTLY BELOW 500 FT OR SO. WINDS WILL TAPER LATE THIS
AFTERNOON BUT REMAIN BREEZY ALL NIGHT. MAY PERIODICALLY SEE
VISIBILITIES DROP BRIEFLY TO IFR AT KLBB THIS AFTERNOON. VERTICAL WIND
SHEAR SHOULD NOT BE TOO MUCH OF AN ISSUE THIS AFTERNOON ALTHOUGH
IT MAY BECOME AN ISSUE OVERNIGHT AS THE BOUNDARY LAYER DECOUPLES
AND WE WILL HAVE TO MONITOR TRENDS.
&&
.PREV DISCUSSION... /ISSUED 545 AM CST SAT NOV 26 2011/
..VERY STRONG WINDS DEVELOPING TODAY...
AVIATION...
TWO CHALLENGES OF CONCERN TODAY...THE FIRST IS THE DEVELOPMENT OF
SOME POST-FRONTAL MVFR LAYERS FROM CLOVIS EAST TO NEAR CHILDRESS
AND THE SECOND AND MORE PROLONGED THREAT IS THAT OF STRONG
NORTHERLY WINDS FOR MUCH OF THE DAY. BEHAVIOR OF MVFR CIGS IS SUCH
THAT THEY QUICKLY TREND VFR AS COLDER AND DRIER AIR PUSHES
SOUTH...SO WILL ONLY CARRY A TEMPO GROUP AT LBB THIS MORNING. CDS
HAS ALREADY RISEN TO VFR LAYERS IN THIS DRIER AIR.
GREATEST AVIATION HAZARD IS STRONG NORTHERLY WINDS INCREASING TO
BETWEEN 30 AND 40 KNOTS LATER THIS MORNING. THUS FAR WE HAVE LITTLE
REASON TO DOUBT THE FEW MODELS INDICATING SUCH HIGH WINDS AS 50
KNOTS WAS RECENTLY SAMPLED BY THE LBB WSR-88D VAD WIND PROFILE A
MERE 1K FEET AGL. ONCE MIXING LAYERS DEEPEN AROUND 15Z...EXPECT
OCCASIONAL GUSTS TO APPROACH 50 KNOTS WITH SUSTAINED SPEEDS
RESIDING BETWEEN 30 AND 35 KNOTS. AN AIRPORT WX WARNING FOR HIGH
WINDS WILL BE ISSUED SHORTLY FOR LBB STARTING ~15Z. BLOWING DUST
SHOULD NOT BE AS SEVERE AS WITH A WESTERLY WIND EVENT...BUT TEMPO
5SM APPEARS REASONABLE AT LBB. EXPECT WINDS AND STRONG GUSTS TO
QUICKLY SUBSIDE AROUND SUNSET.
PREV DISCUSSION... /ISSUED 407 AM CST SAT NOV 26 2011/
SHORT TERM...
SHARP UPPER TROUGH CURRENTLY BISECTING THE CONUS WILL INTENSIFY
TODAY AS A VORTICITY MAXIMUM SLIDES SOUTHWARD FROM NERN COLORADO
AND INTO THE BASE OF THE TROUGH. THIS PROCESS IS ALREADY SENDING
A POLAR FRONT SOUTH FROM THE PANHANDLE WHICH SHOULD CLEAR THE CWA
BY MID-MORNING. OF GREATER INTEREST IS A STRONG HEIGHT GRADIENT
TAKING AIM ON MUCH OF THE HIGH PLAINS BY MIDDAY RESULTING IN
NEARLY 100 KNOTS AND 50-60 KNOTS AT 500MB AND 700MB RESPECTIVELY.
DEEP SUBSIDENCE ON THE BACKSIDE OF THE UPPER TROUGH WILL FOSTER
STRONG LOW-LEVEL DRYING TO THE TUNE OF SINGLE-DIGIT DEWPOINTS ON
THE CAPROCK BY EARLY AFTERNOON. EVEN THOUGH MAX TEMPS WILL BE
STUNTED 10 DEG BELOW NORMAL...DEWPOINT DEPRESSIONS RISING TO 40
DEG SHOULD ONLY AID IN DEEPER DRY ADIABATIC LAPSE RATES AND HIGHER
MOMENTUM TRANSFER OVER TIME. CONSIDERING THE MID-LEVEL JET CORE
WILL RESIDE NEAR/JUST WEST OF I-27 AND MAX PRESSURE RISES WILL BE
FAVORABLY TIMED...WE FEEL A HIGH WIND WARNING IS IN ORDER FOR MUCH
OF THE CAPROCK WITH A WIND ADVISORY ELSEWHERE. ALTHOUGH OUR LOCAL
HIGH WIND CHECKLIST FALLS A BIT SHORT OF SOLID HIGH WIND
CRITERIA...THIS PATTERN OF CAA AND DEEP NORTHERLY FLOW COMBINED
WITH SHARP LOW-LEVEL DRYING IS ENOUGH TO TIP THE SCALE IN FAVOR OF
A LOW-END HIGH WIND WARNING SCENARIO. IF THE RUC AND GFS ARE
CORRECT...THE HIGH WIND WARNING MAY NEED TO BE EXPANDED AREA WIDE
THIS MORNING. THE MEMPHIS WTM SITE IS ALREADY ATTEMPTING TO CRASH
THIS PARTY WITH A RECENT GUST TO 55 MPH...HOWEVER CONFIDENCE IN
SUCH A WIDESPREAD AND PROLONGED HIGH WIND THREAT AREA IS NOT
SUFFICIENTLY HIGH AT THIS TIME...BUT LATER FORECASTS WILL REVISIT
THIS POTENTIAL.
A BROAD SURFACE RIDGE WILL THEN OVERSPREAD THE CAPROCK TONIGHT
RESULTING IN LIGHTER WINDS THAN IN THE ROLLING PLAINS. EXPECT
STRONG RADIATIONAL COOLING ON THE CAPROCK TO GARNER SOME OF
COLDEST OVERNIGHT LOWS IN SEVERAL DAYS.
LONG TERM...
REMAINDER OF THE FORECAST PACKAGE IS RELATIVELY QUIET COMPARED
WITH ISSUES FOR TODAY. DEEP NORTHERLY FLOW ALOFT WILL REMAIN IN
PLACE BUT SURFACE WINDS WILL GRADUALLY TRANSITION TO THE WEST LATE
SUNDAY INTO MONDAY. HIGHS TOMORROW WILL AT OR A TICK UNDER NORMAL
FOR THIS TIME OF YEAR BUT WILL REBOUND TO AROUND 10 DEGREES ABOVE
NORMAL ON MONDAY AS DECENT DOWNSLOPE FLOW AND AMPLE SUNSHINE HELP
TO BOOST HIGH TEMPS.
A SECOND COLD FRONT WILL ARRIVE LATE MONDAY INTO TUESDAY ONCE
AGAIN DROPPING HIGH TEMPERATURES BELOW NORMAL FOR TUESDAY FOR
TUESDAY AND POSSIBLY BUMPING WIND SPEEDS UP INTO THE BREEZY
RANGE. RIGHT NOW IT APPEARS THAT WIND SPEEDS WILL NOT BE AS HIGH
AS WE ARE EXPECTING FOR TODAY. SIMILAR CYCLE WILL THEN ENSUE WITH
WEST TO SOUTHWEST WINDS ON WEDNESDAY HELPING TO BRING TEMPERATURES
BACK ABOVE NORMAL FOR A DAY.
STILL ARE SOME CONSIDERABLE DIFFERENCES FOR THE END OF NEXT WEEK
AND THE END OF THIS FORECAST. ALL MODELS ARE NOW DEVELOPING A
CLOSED LOW SOMEWHERE IN THE WESTERN PART OF THE COUNTRY WITH A
STRONG COLD FRONT EXPECTED TO ARRIVE SOMETIME LATE THURSDAY INTO
FRIDAY. GFS IS A FULL DAY FASTER WITH THE COLD FRONT ARRIVAL AND
BRINGS A PRETTY COLD ARCTIC AIRMASS INTO THE REGION. THE ECMWF IS
NOT AS COLD AS THE GFS AND RAPIDLY MIXES OUT THE COLD AIR IN
ADVANCE OF THE APPROACHING CLOSED LOW AND RAPIDLY PULLS IN GULF
MOISTURE. GFS KEEPS THE COLD AIRMASS OVER THE REGION EVEN WITH THE
ADVANCING LOW HEADING TOWARDS THE REGION. WILL HOLD OFF MAKING
CHANGES TO THE LAST TWO DAYS OF THE FORECAST UNTIL THE MODELS
SETTLE DOWN A BIT AND COME INTO BETTER AGREEMENT...BUT THE
POTENTIAL IS THERE FOR SOME PRETTY CHILLY DAYS BY THE END OF NEXT
WEEK INTO NEXT WEEKEND.
JORDAN
FIRE WEATHER...
STRONG LOW-LEVEL DRYING BEHIND A COLD FRONT TODAY COMBINED WITH
NORTHERLY WINDS OF 25-35 MPH AT THE 20-FOOT LEVEL WILL CREATE
PERIODS OF CRITICAL FIRE WEATHER CONDITIONS PRIMARILY OVER THE
SOUTHERN SOUTH PLAINS. ALTHOUGH WIND SPEEDS ARE MORE THAN
SUFFICIENT...BELOW NORMAL TEMPERATURES AND MARGINAL RELATIVE
HUMIDITY VALUES ARE NOT FULLY SUPPORTIVE OF A RED FLAG WARNING. WE
HAVE INSTEAD ISSUED A FIRE DANGER STATEMENT TO HIGHLIGHT PERIODS
THIS AFTERNOON WHEN RELATIVE HUMIDITIES SHOULD BRIEFLY DIP TO
AROUND 15-20 PERCENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 46 22 57 32 66 / 0 0 0 0 0
TULIA 46 24 58 31 70 / 0 0 0 0 0
PLAINVIEW 47 24 58 32 70 / 0 0 0 0 0
LEVELLAND 49 24 59 32 69 / 0 0 0 0 0
LUBBOCK 49 26 59 32 69 / 0 0 0 0 0
DENVER CITY 51 26 59 35 69 / 0 0 0 0 0
BROWNFIELD 49 26 60 32 70 / 0 0 0 0 0
CHILDRESS 52 30 57 30 66 / 0 0 0 0 0
SPUR 52 27 59 34 70 / 0 0 0 0 0
ASPERMONT 54 30 58 32 69 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR THE FOLLOWING
ZONES: TXZ026-031-032-037-038-043-044.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR THE FOLLOWING
ZONES: TXZ021>025-027>030-033>036-039>042.
&&
$$
99/99/26
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1005 AM CST SAT NOV 26 2011
.DISCUSSION...COLD FRONT IS PROGRESSING THROUGH WEST AND CENTRAL
TEXAS THIS MORNING. WIND SHIFT HAS PUSHED INTO THE CWA BUT FEEL
THIS IS WITH A PRE FRONTAL TROUGH. WITH JUST SLIGHT DPT DROP AND
WINDS REMAIN LIGHT. REAL FRONTAL BOUNDARY A LITTLE TOUGH TO PICK
OUT...BUT SEEMS TO BE JUST THROUGH DALLAS...TO FREDERICKSBURG...TO
DEL RIO. PRECIPITATION ASSOCIATED WITH THE FRONT SO FAR HAS BEEN
RATHER LIMITED IN THE EAST...WITH ISOLATED TO AT TIMES SCATTERED
LIGHT SHOWERS IN THE WEST. LATEST RUC MODEL KEEPS THE BULK OF THE
PRECIP JUST INTO THE NORTHERN PARTS OF THE CWA. HRRR MODEL HOWEVER
SHOWS SCATTERED CONVECTION DEVELOPING ACROSS ENTIRE AREA. BOTH
MODELS INDICATE INCREASING COVERAGE OF MORE STRATIFORM PRECIP
RIGHT ALONG THE FRONT AS IT NEARS THE COAST...WHERE THE DEEPEST
MOISTURE EXISTS...12Z CRP SOUNDING HAD 1.6 PWAT. HAVE ADJUSTED
MORNING POPS SOME TO ACCOUNT FOR LACK OF CONVECTION...HOWEVER
STILL THINK WE SHOULD SEE SOME DEVELOPMENT AS TEMPS INCREASE. HAVE
ALSO ADJUSTED TEMPS TO ACCOUNT FOR WARMER TEMPS FAR EAST WHERE
CLOUDS REMAIN BROKEN AND TEMPS ALREADY APPROACHING 80 DEGREES.
&&
.PREV DISCUSSION... /ISSUED 538 AM CST SAT NOV 26 2011/
DISCUSSION...SEE AVIATION SECTION BELOW.
AVIATION...CURRENTLY VFR CIGS/VSBYS ARE ACROSS S TX...HOWEVER SCT
TO NUM SHRA`S/TSRA`S ARE EXPECTED AHD AND ALONG A STRONG COLD
FRONT LATER THIS MORNING INTO THE EARLY AFTERNOON. BEST CHC OF
TSRA`S WILL BE ACROSS VCT AREA WITH LESSER CHCS FARTHER S AND W.
AREAS BEING EFFECTED BY CONVECTION WILL LIKELY LOWER TO MVFR AND
POSSIBLY IFR LEVELS AT TIMES. AS THE COLD FRONT MOVES THROUGH S
TX...CONDITIONS WILL IMPROVE TO VFR AND WINDS WILL SHIFT TO THE N AND
INCREASE TO 20 TO 30 KNOTS WITH GUSTS UP TO AROUND 40
KNOTS...MAINLY FROM LRD TO ALI TO CRP. WENT WITH GUSTS TO AROUND
30-33KT IN THE TAFS AS THIS WILL BE MORE COMMON. NLY WINDS WILL
DECREASE OVRNIGHT BUT RESTRENGTHEN ON SUNDAY.
PREV DISCUSSION... /ISSUED 459 AM CST SAT NOV 26 2011/
SHORT TERM (TODAY THROUGH SUNDAY)...A LONG WAVE TROF DRAPED ACROSS
THE TX PANHANDLE SOUTHWARD INTO MEX WILL MOVE ACROSS THE REGION
TODAY BRINGING WITH IT A STRONG COLD FRONT. AHD OF THE COLD
FRONT...DEEP MOISTURE WILL COMBINE WITH UPPER JET...EMBEDDED SHORT
WAVE...LG OMEGA...AND DECENT LOW LEVEL CONVERGENCE TO PRODUCE
SCT/NUM SHRA`S/TSRA`S. THE ACTIVITY IS EXPECTED TO INCREASE IN
COVERAGE AS IT MOVES E TOWARD THE COAST DUE TO LOW TO MOD CAPE ALONG
THE COAST AND OVER THE GULF WATERS. THE CAPE AND THE LI`S ARE NOT
IMPRESSIVE AND THERE WILL BE LITTLE TO NO SHEAR...THEREFORE AM NOT
EXPECTING ANY ORGANIZED SVR STORMS. SOME STORMS COULD BECOME STRONG
WITH GUSTS TO AROUND 40KT AND SMALL HAIL. THE BEST CHC FOR PRECIP
WILL BE ACROSS THE NW CWA THRU MID MORNING THEN MOVG E WITH INCREASING
CHCS ACROSS THE E AND NE CWA BY AROUND NOON INTO EARLY AFTERNOON.
THE SYSTEM WILL THEN EXIT THE AREA THRU LATE AFTERNOON.
THE MAIN ISSUE BEHIND THE COLD FRONT WILL BE WINDS. THE MODELS SHOW
40KT OFF THE DECK ALONG WITH DECENT LAPSE RATES THIS AFTERNOON INTO
TONIGHT...ESPECIALLY ACROSS THE SRN CWA AND ALONG THE COASTAL
COUNTIES. THEREFORE WENT WITH A WIND ADVISORY FOR THOSE AREAS WHERE
GUSTS TO 40 MPH WILL BE MOST FREQUENT. IT WILL BE WINDY ACROSS THE
NRN CWA AS WELL...BUT SHOULD REMAIN BELOW ADVISORY LEVELS. WINDS
RELAX SOMEWHAT OVERNIGHT BUT THEN RESTRENGTHEN ON SUNDAY BUT THE WINDS
SHOULD REMAIN BELOW ADVISORY LEVELS.
WITH ONGOING CAA INTO TONIGHT...MN TEMPS ARE EXPECTED TO DIP INTO
THE MID 30S ACROSS THE NW CWA TO MID 40S ALONG THE COAST. THE
OVERNIGHT WINDS WILL REMAIN ELEVATED AND NOT ALLOW THE TEMPS TO DROP
MUCH MORE THAN THAT. DESPITE SUNNY SKIES...HIGHS ON SUNDAY WILL BE
MUCH COOLER WITH AREA WIDE 60S.
MARINE...SCT TO NUM SHRA`S/TSRA`S CAN BE EXPECTED TODAY AHD AND
ALONG A STRONG COLD FRONT THAT WILL MOVE ACROSS THE BAYS AND COASTAL
WATERS THIS AFTERNOON. WINDS WILL SHIFT TO THE N AND RAPIDLY
INCREASE TO ADVISORY LEVELS ACROSS THE BAYS AND GALE FORCE ACROSS
THE COASTAL WATERS. A GALE WARNING IS IN EFFECT FOR THE GULF WATERS
AND AN SCA IS IN EFFECT FOR THE BAYS. THE GALE FORCE WINDS ARE
EXPECTED TO DECREASE BY SUN MORNING BUT REMAIN HIGH END SCA THROUGH
SUNDAY NIGHT.
FIRE WEATHER...A COLD FRONT IS EXPECTED TO PUSH ACROSS S TX LATE
TODAY WITH STRENGTHENING N WINDS DVLPG IN ITS WAKE. ALTHOUGH DRIER
AIR WILL BE FILTERING INTO S TX...RH VALUES ARE EXPECTED TO REMAIN
ABV CRITICAL THRESHOLDS THROUGH TODAY AND TONIGHT. THEREFORE AM NOT
EXPECTING FIRE WEATHER CONDITIONS THRU TONIGHT. HOWEVER...MUCH LOWER
RH VALUES IN THE TEENS WILL BE IN PLACE ON SUNDAY AND WINDS WILL BE
BREEZY TO WINDY LEADING TO CRITICAL FIRE DANGER CONDITIONS. A FIRE
WEATHER WATCH IS IN EFFECT FOR SUNDAY.
LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...COLD DRY AIRMASS WILL
REMAIN OVER SOUTH TEXAS SUNDAY NIGHT WITH WINDS RELAXING. WENT CLOSE
TO THE COLDER MET GUIDANCE FOR MINIMUMS WITH BELOW FREEZING TEMPS
EXPECTED FOR THE INLAND COASTAL PLAINS UP INTO THE NORTHERN BRUSH
COUNTRY. WENT AHEAD AND ISSUED A FREEZE WATCH FOR THESE AREAS FOR
LATE SUNDAY NIGHT. THE ANOMALOUS DEEP UPPER LOW WILL MOVE ACROSS THE
SOUTHEAST UNITED STATES MONDAY AND TUESDAY. THE OFFSHORE FLOW WILL
WEAKEN MONDAY BUT INCREASE AGAIN ON TUESDAY. HIGH PRESSURE WILL
SURGE DOWN THE PLAINS AFTER A NORTHERN STREAM SHORT WAVE TROUGH
MOVES INTO THE UPPER MIDWEST TUESDAY WITH AN INCREASE IN WINDS
EXPECTED TUESDAY AFTERNOON. TEMPERATURES WILL ALMOST BE BACK TO
NORMAL MONDAY/TUESDAY BUT WILL FALL BACK TO BELOW NORMAL FOR
WEDNESDAY. A BRIEF WARM UP IS EXPECTED FOR THURSDAY. MEDIUM RANGE
MODELS SHOW ENERGY DIVING OUT OF THE GULF OF ALASKA INTO THE PACIFIC
NORTHWEST WEDNESDAY BUT THE MODELS DIVERGE FROM THERE ON EVOLUTION
OF THE UPPER LOW BECOMING CUTOFF FROM THE NORTHERN STREAM AND MOVING
INTO THE DESERT SOUTHWEST BY FRIDAY. POLAR AIRMASS IS EXPECTED TO
MOVE DOWN THROUGH THE PLAINS INTO SOUTH TEXAS ON FRIDAY. INCREASING
ISENTROPIC LIFT SHOULD LEAD TO AN INCREASED CLOUD COVER. 00Z GFS
GENERATED TOO MUCH PRECIP WITH THE UPPER SYSTEM EXPECTED TO BE WELL
TO THE WEST. KEPT POPS AT 10 PERCENT FOR NOW FOR FRIDAY BUT SHOWED
TEMPERATURES 5 TO 10 DEGREES BELOW NORMAL WITH WINDS INCREASING FROM
THE NORTHEAST. FIRE WEATHER CONCERNS WILL PERSIST FROM MONDAY AND
TUESDAY DUE TO A VERY DRY AIRMASS AND MODEST NORTHWEST WINDS MONDAY
AND GUSTY NORTH WINDS TUESDAY. AN ELEVATED FIRE DANGER RISK IS
EXPECTED FOR BOTH DAYS.
89/TMT
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 78 46 64 33 71 / 50 10 0 0 0
VICTORIA 75 39 61 29 67 / 70 10 0 0 0
LAREDO 76 42 65 36 75 / 30 10 0 0 0
ALICE 78 43 64 32 73 / 40 10 0 0 0
ROCKPORT 76 49 62 40 67 / 60 10 0 0 0
COTULLA 73 36 63 30 73 / 30 10 0 0 0
KINGSVILLE 78 45 64 30 73 / 50 10 0 0 0
NAVY CORPUS 76 51 63 42 68 / 50 10 0 0 0
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...FREEZE WATCH LATE SUNDAY NIGHT FOR THE FOLLOWING ZONES: BEE...
CALHOUN...GOLIAD...JIM WELLS...KLEBERG...LA SALLE...LIVE
OAK...MCMULLEN...NUECES...REFUGIO...SAN PATRICIO...VICTORIA.
FIRE WEATHER WATCH FROM SUNDAY MORNING THROUGH SUNDAY AFTERNOON
FOR THE FOLLOWING ZONES: ARANSAS...BEE...CALHOUN...DUVAL...
GOLIAD...JIM WELLS...KLEBERG...LA SALLE...LIVE OAK...
MCMULLEN...NUECES...REFUGIO...SAN PATRICIO...VICTORIA...
WEBB.
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR THE FOLLOWING
ZONES: ARANSAS...CALHOUN...DUVAL...JIM WELLS...KLEBERG...
NUECES...REFUGIO...SAN PATRICIO...WEBB.
GM...GALE WARNING FROM 6 PM THIS EVENING TO 6 AM CST SUNDAY FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM BAFFIN BAY
TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS
TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM CST SUNDAY
FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY
TO PORT ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO
PORT O`CONNOR.
&&
$$
PZ/83...SHORT TERM
TT/89...LONG TERM
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
545 AM CST SAT NOV 26 2011
...VERY STRONG WINDS DEVELOPING TODAY...
.AVIATION...
TWO CHALLENGES OF CONCERN TODAY...THE FIRST IS THE DEVELOPMENT OF
SOME POST-FRONTAL MVFR LAYERS FROM CLOVIS EAST TO NEAR CHILDRESS
AND THE SECOND AND MORE PROLONGED THREAT IS THAT OF STRONG
NORTHERLY WINDS FOR MUCH OF THE DAY. BEHAVIOR OF MVFR CIGS IS SUCH
THAT THEY QUICKLY TREND VFR AS COLDER AND DRIER AIR PUSHES
SOUTH...SO WILL ONLY CARRY A TEMPO GROUP AT LBB THIS MORNING. CDS
HAS ALREADY RISEN TO VFR LAYERS IN THIS DRIER AIR.
GREATEST AVIATION HAZARD IS STRONG NORTHERLY WINDS INCREASING TO
BETWEEN 30 AND 40 KNOTS LATER THIS MORNING. THUS FAR WE HAVE LITTLE
REASON TO DOUBT THE FEW MODELS INDICATING SUCH HIGH WINDS AS 50
KNOTS WAS RECENTLY SAMPLED BY THE LBB WSR-88D VAD WIND PROFILE A
MERE 1K FEET AGL. ONCE MIXING LAYERS DEEPEN AROUND 15Z...EXPECT
OCCASIONAL GUSTS TO APPROACH 50 KNOTS WITH SUSTAINED SPEEDS
RESIDING BETWEEN 30 AND 35 KNOTS. AN AIRPORT WX WARNING FOR HIGH
WINDS WILL BE ISSUED SHORTLY FOR LBB STARTING ~15Z. BLOWING DUST
SHOULD NOT BE AS SEVERE AS WITH A WESTERLY WIND EVENT...BUT TEMPO
5SM APPEARS REASONABLE AT LBB. EXPECT WINDS AND STRONG GUSTS TO
QUICKLY SUBSIDE AROUND SUNSET.
&&
.PREV DISCUSSION... /ISSUED 407 AM CST SAT NOV 26 2011/
SHORT TERM...
SHARP UPPER TROUGH CURRENTLY BISECTING THE CONUS WILL INTENSIFY
TODAY AS A VORTICITY MAXIMUM SLIDES SOUTHWARD FROM NERN COLORADO
AND INTO THE BASE OF THE TROUGH. THIS PROCESS IS ALREADY SENDING
A POLAR FRONT SOUTH FROM THE PANHANDLE WHICH SHOULD CLEAR THE CWA
BY MID-MORNING. OF GREATER INTEREST IS A STRONG HEIGHT GRADIENT
TAKING AIM ON MUCH OF THE HIGH PLAINS BY MIDDAY RESULTING IN
NEARLY 100 KNOTS AND 50-60 KNOTS AT 500MB AND 700MB RESPECTIVELY.
DEEP SUBSIDENCE ON THE BACKSIDE OF THE UPPER TROUGH WILL FOSTER
STRONG LOW-LEVEL DRYING TO THE TUNE OF SINGLE-DIGIT DEWPOINTS ON
THE CAPROCK BY EARLY AFTERNOON. EVEN THOUGH MAX TEMPS WILL BE
STUNTED 10 DEG BELOW NORMAL...DEWPOINT DEPRESSIONS RISING TO 40
DEG SHOULD ONLY AID IN DEEPER DRY ADIABATIC LAPSE RATES AND HIGHER
MOMENTUM TRANSFER OVER TIME. CONSIDERING THE MID-LEVEL JET CORE
WILL RESIDE NEAR/JUST WEST OF I-27 AND MAX PRESSURE RISES WILL BE
FAVORABLY TIMED...WE FEEL A HIGH WIND WARNING IS IN ORDER FOR MUCH
OF THE CAPROCK WITH A WIND ADVISORY ELSEWHERE. ALTHOUGH OUR LOCAL
HIGH WIND CHECKLIST FALLS A BIT SHORT OF SOLID HIGH WIND
CRITERIA...THIS PATTERN OF CAA AND DEEP NORTHERLY FLOW COMBINED
WITH SHARP LOW-LEVEL DRYING IS ENOUGH TO TIP THE SCALE IN FAVOR OF
A LOW-END HIGH WIND WARNING SCENARIO. IF THE RUC AND GFS ARE
CORRECT...THE HIGH WIND WARNING MAY NEED TO BE EXPANDED AREA WIDE
THIS MORNING. THE MEMPHIS WTM SITE IS ALREADY ATTEMPTING TO CRASH
THIS PARTY WITH A RECENT GUST TO 55 MPH...HOWEVER CONFIDENCE IN
SUCH A WIDESPREAD AND PROLONGED HIGH WIND THREAT AREA IS NOT
SUFFICIENTLY HIGH AT THIS TIME...BUT LATER FORECASTS WILL REVISIT
THIS POTENTIAL.
A BROAD SURFACE RIDGE WILL THEN OVERSPREAD THE CAPROCK TONIGHT
RESULTING IN LIGHTER WINDS THAN IN THE ROLLING PLAINS. EXPECT
STRONG RADIATIONAL COOLING ON THE CAPROCK TO GARNER SOME OF
COLDEST OVERNIGHT LOWS IN SEVERAL DAYS.
LONG TERM...
REMAINDER OF THE FORECAST PACKAGE IS RELATIVELY QUIET COMPARED
WITH ISSUES FOR TODAY. DEEP NORTHERLY FLOW ALOFT WILL REMAIN IN
PLACE BUT SURFACE WINDS WILL GRADUALLY TRANSITION TO THE WEST LATE
SUNDAY INTO MONDAY. HIGHS TOMORROW WILL AT OR A TICK UNDER NORMAL
FOR THIS TIME OF YEAR BUT WILL REBOUND TO AROUND 10 DEGREES ABOVE
NORMAL ON MONDAY AS DECENT DOWNSLOPE FLOW AND AMPLE SUNSHINE HELP
TO BOOST HIGH TEMPS.
A SECOND COLD FRONT WILL ARRIVE LATE MONDAY INTO TUESDAY ONCE
AGAIN DROPPING HIGH TEMPERATURES BELOW NORMAL FOR TUESDAY FOR
TUESDAY AND POSSIBLY BUMPING WIND SPEEDS UP INTO THE BREEZY
RANGE. RIGHT NOW IT APPEARS THAT WIND SPEEDS WILL NOT BE AS HIGH
AS WE ARE EXPECTING FOR TODAY. SIMILAR CYCLE WILL THEN ENSUE WITH
WEST TO SOUTHWEST WINDS ON WEDNESDAY HELPING TO BRING TEMPERATURES
BACK ABOVE NORMAL FOR A DAY.
STILL ARE SOME CONSIDERABLE DIFFERENCES FOR THE END OF NEXT WEEK
AND THE END OF THIS FORECAST. ALL MODELS ARE NOW DEVELOPING A
CLOSED LOW SOMEWHERE IN THE WESTERN PART OF THE COUNTRY WITH A
STRONG COLD FRONT EXPECTED TO ARRIVE SOMETIME LATE THURSDAY INTO
FRIDAY. GFS IS A FULL DAY FASTER WITH THE COLD FRONT ARRIVAL AND
BRINGS A PRETTY COLD ARCTIC AIRMASS INTO THE REGION. THE ECMWF IS
NOT AS COLD AS THE GFS AND RAPIDLY MIXES OUT THE COLD AIR IN
ADVANCE OF THE APPROACHING CLOSED LOW AND RAPIDLY PULLS IN GULF
MOISTURE. GFS KEEPS THE COLD AIRMASS OVER THE REGION EVEN WITH THE
ADVANCING LOW HEADING TOWARDS THE REGION. WILL HOLD OFF MAKING
CHANGES TO THE LAST TWO DAYS OF THE FORECAST UNTIL THE MODELS
SETTLE DOWN A BIT AND COME INTO BETTER AGREEMENT...BUT THE
POTENTIAL IS THERE FOR SOME PRETTY CHILLY DAYS BY THE END OF NEXT
WEEK INTO NEXT WEEKEND.
JORDAN
FIRE WEATHER...
STRONG LOW-LEVEL DRYING BEHIND A COLD FRONT TODAY COMBINED WITH
NORTHERLY WINDS OF 25-35 MPH AT THE 20-FOOT LEVEL WILL CREATE
PERIODS OF CRITICAL FIRE WEATHER CONDITIONS PRIMARILY OVER THE
SOUTHERN SOUTH PLAINS. ALTHOUGH WIND SPEEDS ARE MORE THAN
SUFFICIENT...BELOW NORMAL TEMPERATURES AND MARGINAL RELATIVE
HUMIDITY VALUES ARE NOT FULLY SUPPORTIVE OF A RED FLAG WARNING. WE
HAVE INSTEAD ISSUED A FIRE DANGER STATEMENT TO HIGHLIGHT PERIODS
THIS AFTERNOON WHEN RELATIVE HUMIDITIES SHOULD BRIEFLY DIP TO
AROUND 15-20 PERCENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 46 22 57 32 66 / 0 0 0 0 0
TULIA 46 24 58 31 70 / 0 0 0 0 0
PLAINVIEW 47 24 58 32 70 / 0 0 0 0 0
LEVELLAND 49 24 59 32 69 / 0 0 0 0 0
LUBBOCK 49 26 59 32 69 / 0 0 0 0 0
DENVER CITY 51 26 59 35 69 / 0 0 0 0 0
BROWNFIELD 49 26 60 32 70 / 0 0 0 0 0
CHILDRESS 52 30 57 30 66 / 0 0 0 0 0
SPUR 52 27 59 34 70 / 0 0 0 0 0
ASPERMONT 54 30 58 32 69 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR THE FOLLOWING
ZONES: TXZ025-026-031-032-037>044.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR THE FOLLOWING
ZONES: TXZ021>024-027>030-033>036.
&&
$$
93/14/93
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
407 AM CST SAT NOV 26 2011
.SHORT TERM...
SHARP UPPER TROUGH CURRENTLY BISECTING THE CONUS WILL INTENSIFY
TODAY AS A VORTICITY MAXIMUM SLIDES SOUTHWARD FROM NERN COLORADO
AND INTO THE BASE OF THE TROUGH. THIS PROCESS IS ALREADY SENDING
A POLAR FRONT SOUTH FROM THE PANHANDLE WHICH SHOULD CLEAR THE CWA
BY MID-MORNING. OF GREATER INTEREST IS A STRONG HEIGHT GRADIENT
TAKING AIM ON MUCH OF THE HIGH PLAINS BY MIDDAY RESULTING IN
NEARLY 100 KNOTS AND 50-60 KNOTS AT 500MB AND 700MB RESPECTIVELY.
DEEP SUBSIDENCE ON THE BACKSIDE OF THE UPPER TROUGH WILL FOSTER
STRONG LOW-LEVEL DRYING TO THE TUNE OF SINGLE-DIGIT DEWPOINTS ON
THE CAPROCK BY EARLY AFTERNOON. EVEN THOUGH MAX TEMPS WILL BE
STUNTED 10 DEG BELOW NORMAL...DEWPOINT DEPRESSIONS RISING TO 40
DEG SHOULD ONLY AID IN DEEPER DRY ADIABATIC LAPSE RATES AND HIGHER
MOMENTUM TRANSFER OVER TIME. CONSIDERING THE MID-LEVEL JET CORE
WILL RESIDE NEAR/JUST WEST OF I-27 AND MAX PRESSURE RISES WILL BE
FAVORABLY TIMED...WE FEEL A HIGH WIND WARNING IS IN ORDER FOR MUCH
OF THE CAPROCK WITH A WIND ADVISORY ELSEWHERE. ALTHOUGH OUR LOCAL
HIGH WIND CHECKLIST FALLS A BIT SHORT OF SOLID HIGH WIND
CRITERIA...THIS PATTERN OF CAA AND DEEP NORTHERLY FLOW COMBINED
WITH SHARP LOW-LEVEL DRYING IS ENOUGH TO TIP THE SCALE IN FAVOR OF
A LOW-END HIGH WIND WARNING SCENARIO. IF THE RUC AND GFS ARE
CORRECT...THE HIGH WIND WARNING MAY NEED TO BE EXPANDED AREA WIDE
THIS MORNING. THE MEMPHIS WTM SITE IS ALREADY ATTEMPTING TO CRASH
THIS PARTY WITH A RECENT GUST TO 55 MPH...HOWEVER CONFIDENCE IN
SUCH A WIDESPREAD AND PROLONGED HIGH WIND THREAT AREA IS NOT
SUFFICIENTLY HIGH AT THIS TIME...BUT LATER FORECASTS WILL REVISIT
THIS POTENTIAL.
A BROAD SURFACE RIDGE WILL THEN OVERSPREAD THE CAPROCK TONIGHT
RESULTING IN LIGHTER WINDS THAN IN THE ROLLING PLAINS. EXPECT
STRONG RADIATIONAL COOLING ON THE CAPROCK TO GARNER SOME OF
COLDEST OVERNIGHT LOWS IN SEVERAL DAYS.
&&
.LONG TERM...
REMAINDER OF THE FORECAST PACKAGE IS RELATIVELY QUIET COMPARED
WITH ISSUES FOR TODAY. DEEP NORTHERLY FLOW ALOFT WILL REMAIN IN
PLACE BUT SURFACE WINDS WILL GRADUALLY TRANSITION TO THE WEST LATE
SUNDAY INTO MONDAY. HIGHS TOMORROW WILL AT OR A TICK UNDER NORMAL
FOR THIS TIME OF YEAR BUT WILL REBOUND TO AROUND 10 DEGREES ABOVE
NORMAL ON MONDAY AS DECENT DOWNSLOPE FLOW AND AMPLE SUNSHINE HELP
TO BOOST HIGH TEMPS.
A SECOND COLD FRONT WILL ARRIVE LATE MONDAY INTO TUESDAY ONCE
AGAIN DROPPING HIGH TEMPERATURES BELOW NORMAL FOR TUESDAY FOR
TUESDAY AND POSSIBLY BUMPING WIND SPEEDS UP INTO THE BREEZY
RANGE. RIGHT NOW IT APPEARS THAT WIND SPEEDS WILL NOT BE AS HIGH
AS WE ARE EXPECTING FOR TODAY. SIMILAR CYCLE WILL THEN ENSUE WITH
WEST TO SOUTHWEST WINDS ON WEDNESDAY HELPING TO BRING TEMPERATURES
BACK ABOVE NORMAL FOR A DAY.
STILL ARE SOME CONSIDERABLE DIFFERENCES FOR THE END OF NEXT WEEK
AND THE END OF THIS FORECAST. ALL MODELS ARE NOW DEVELOPING A
CLOSED LOW SOMEWHERE IN THE WESTERN PART OF THE COUNTRY WITH A
STRONG COLD FRONT EXPECTED TO ARRIVE SOMETIME LATE THURSDAY INTO
FRIDAY. GFS IS A FULL DAY FASTER WITH THE COLD FRONT ARRIVAL AND
BRINGS A PRETTY COLD ARCTIC AIRMASS INTO THE REGION. THE ECMWF IS
NOT AS COLD AS THE GFS AND RAPIDLY MIXES OUT THE COLD AIR IN
ADVANCE OF THE APPROACHING CLOSED LOW AND RAPIDLY PULLS IN GULF
MOISTURE. GFS KEEPS THE COLD AIRMASS OVER THE REGION EVEN WITH THE
ADVANCING LOW HEADING TOWARDS THE REGION. WILL HOLD OFF MAKING
CHANGES TO THE LAST TWO DAYS OF THE FORECAST UNTIL THE MODELS
SETTLE DOWN A BIT AND COME INTO BETTER AGREEMENT...BUT THE
POTENTIAL IS THERE FOR SOME PRETTY CHILLY DAYS BY THE END OF NEXT
WEEK INTO NEXT WEEKEND.
JORDAN
&&
.FIRE WEATHER...
STRONG LOW-LEVEL DRYING BEHIND A COLD FRONT TODAY COMBINED WITH
NORTHERLY WINDS OF 25-35 MPH AT THE 20-FOOT LEVEL WILL CREATE
PERIODS OF CRITICAL FIRE WEATHER CONDITIONS PRIMARILY OVER THE
SOUTHERN SOUTH PLAINS. ALTHOUGH WIND SPEEDS ARE MORE THAN
SUFFICIENT...BELOW NORMAL TEMPERATURES AND MARGINAL RELATIVE
HUMIDITY VALUES ARE NOT FULLY SUPPORTIVE OF A RED FLAG WARNING. WE
HAVE INSTEAD ISSUED A FIRE DANGER STATEMENT TO HIGHLIGHT PERIODS
THIS AFTERNOON WHEN RELATIVE HUMIDITIES SHOULD BRIEFLY DIP TO
AROUND 15-20 PERCENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 46 22 57 32 66 / 0 0 0 0 0
TULIA 46 24 58 31 70 / 0 0 0 0 0
PLAINVIEW 47 24 58 32 70 / 0 0 0 0 0
LEVELLAND 49 24 59 32 69 / 0 0 0 0 0
LUBBOCK 49 26 59 32 69 / 0 0 0 0 0
DENVER CITY 51 26 59 35 69 / 0 0 0 0 0
BROWNFIELD 49 26 60 32 70 / 0 0 0 0 0
CHILDRESS 52 30 57 30 66 / 0 0 0 0 0
SPUR 52 27 59 34 70 / 0 0 0 0 0
ASPERMONT 54 30 58 32 69 / 0 0 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR THE FOLLOWING
ZONES: TXZ025-026-031-032-037>044.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR THE FOLLOWING
ZONES: TXZ021>024-027>030-033>036.
&&
$$
93/14
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
532 PM CST SUN NOV 27 2011
.SHORT TERM...TONIGHT THROUGH WEDNESDAY
255 PM CST SUN NOV 27 2011
MAIN FORECAST CONCERN IS ON CLOUDS/TEMPERATURES TONIGHT INTO MONDAY.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED TROUGHING OVER BRITISH COLUMBIA...RIDGING FROM SOUTHERN
CALIFORNIA NORTHEASTWARD INTO SOUTHERN MANITOBA...AND TROUGHING FROM
JAMES BAY SOUTHWEST THROUGH WISCONSIN AND DOWN INTO EASTERN TEXAS.
WITH THE FORECAST AREA ON THE WEST SIDE OF THIS LATTER UPPER
TROUGHING...MID TO UPPER LEVEL SUBSIDENCE IS OCCURRING. THIS CAN BE
SEEN ON 12Z SOUNDINGS FROM ABR...MPX AND DVN. ALSO OF NOTE ON THE
MPX AND DVN SOUNDINGS IS A NEAR TO FULLY SATURATED LAYER FROM 910MB
TO AT LEAST 850MB...REPRESENTATIVE OF THE STRATUS DECK IN PLACE AT
THE TIME. LATEST VISIBLE SATELLITE IMAGERY SHOWED THE STRATUS
COVERING THE ENTIRE FORECAST AREA AND EXTENDING WEST TO A
NORTH-SOUTH LINE THROUGH WINDOM MINNESOTA. GOING A LITTLE FARTHER
WEST...A SURFACE RIDGE IS PRESENT ALONG THE DAKOTAS/MINNESOTA
BORDER. NORTHWEST WINDS REMAIN GUSTY AHEAD OF THE RIDGE WITH GUSTS
OF 20-25 KT OVER THE FORECAST AREA. TEMPERATURES HAVE ALSO STRUGGLED
TO RISE MUCH TODAY...DUE TO A COMBINATION OF THE STRATUS LIMITING
DIURNAL HEATING AND 850MB TEMPS OF -9C OBSERVED AT MPX ON ITS 12Z
SOUNDING.
MUCH OF THE SHORT TERM PERIOD LOOKS QUIET FOR THE FORECAST AREA...
THOUGH THERE ARE A FEW FEATURES TO WATCH. FIRST IS THE SOUTHERN END
OF THE CURRENT UPPER TROUGH IN EAST TEXAS. ALL MODELS AGREE ON THE
SOUTHERN END CLOSING OFF INTO AN UPPER LOW OVER THE SOUTHEASTERN
U.S. MONDAY INTO MONDAY NIGHT...WHICH RESULTS IN SURFACE LOW
DEVELOPMENT ON ITS NORTH SIDE OVER KENTUCKY AND TENNESSEE. THE UPPER
AND SURFACE LOWS THEN GET LIFTED NORTHEAST THROUGH THE EASTERN U.S.
FOR TUESDAY INTO WEDNESDAY...IN RESPONSE TO THE CURRENT BRITISH
COLUMBIA TROUGH MOVING THROUGH THE FORECAST AREA ON TUESDAY. AS OF
NOW IT APPEARS ANY DEFORMATION PRECIPITATION ON THE NORTHWEST SIDE
OF THE UPPER AND SURFACE LOWS WILL STAY TO THE SOUTHEAST...THANKS TO
THAT BRITISH COLUMBIA UPPER TROUGH...PERHAPS REACHING AT MOST THE
ROCKFORD ILLINOIS AREA. OTHERWISE...MUCH OF THE REST OF THE TIME THE
FORECAST AREA SHOULD BE DOMINATED BY SUBSIDENCE AND DRY AIR...DUE TO
UPPER RIDGING COMING ACROSS ON MONDAY AND AGAIN TUESDAY NIGHT INTO
WEDNESDAY...RESULTING IN DRY CONDITIONS.
CLOUD COVER FORECAST IS PROBLEMATIC...ESPECIALLY TONIGHT WITH THE
STRATUS STUCK IN PLACE BELOW THE SUBSIDENCE INVERSION. TYPICALLY TO
GET RID OF STRATUS IN THESE CASES...ESPECIALLY THIS TIME OF YEAR
WITH THE VERY LOW SUN ANGLE...THE SURFACE RIDGE NEEDS TO MOVE IN
AND/OR THROUGH. 27.12Z NAM/GFS SEEM TOO AGGRESSIVE BY CLEARING
THINGS OUT BY 21Z IN OUR WESTERN FORECAST AREA TODAY...WHICH IS
ALREADY TOO FAST PER LATEST SATELLITE IMAGERY. FOLLOWED MORE OF AN
IDEA PRESENTED BY THE RUC AND 925MB WIND FORECASTS...WHICH WOULD
SUGGEST CLEARING MAINLY OCCURRING AFTER MIDNIGHT TONIGHT INTO
MID-DAY MONDAY...WORKING FROM NORTHWEST TO SOUTHEAST AS 925MB WINDS
TURN SOUTHWESTERLY. IT IS POSSIBLE GRANT COUNTY STAYS CLOUDY ALL DAY
MONDAY WITH 925MB WINDS STILL FORECAST NEAR CALM OR OUT OF THE
NORTHEAST...SOMETHING THAT WILL HAVE TO BE MONITORED. OTHERWISE...
SHOULD GET A BAND OF MID/HIGH CLOUDS TO COME ACROSS MONDAY NIGHT
INTO TUESDAY WITH THE BRITISH COLUMBIA UPPER TROUGH. MORE HIGH
CLOUDS LOOK TO MOVE THROUGH WEDNESDAY AFTERNOON AS THE UPPER RIDGE
AXIS CROSSES THE FORECAST AREA.
TEMPERATURES ARE ALSO TRICKY. RAISED LOW TEMPERATURES UP FOR MOST
AREAS TONIGHT INTO THE MID TO UPPER 20S...EXCEPT FOR THE FAR WEST
WHERE CLEARING AND LIGHTER WINDS SHOULD ALLOW TEMPS TO TANK INTO THE
UPPER TEENS TO AROUND 20. STILL SHOULD SEE A DECENT AMOUNT OF SUN ON
MONDAY TO ALLOW TEMPS TO CLIMB INTO THE MID 30S TO LOW 40S...AIDED
BY 850MB TEMPS REACHING 4-6C BY LATE AFTERNOON AHEAD OF THE UPPER
TROUGH. LOOK FOR A COOL DOWN ON TUESDAY AS THE UPPER TROUGH
CROSSES...DROPPING 850MB TEMPS DOWN TO -2 TO -4C AND THUS HIGHS INTO
THE LOW TO MID 30S. TUESDAY NIGHT COULD BE QUITE CHILLY WITH A
SURFACE RIDGE CROSSING AND CLEAR SKIES. STAYED WITH A BLEND OF
GUIDANCE THEN. MODERATION IN TEMPERATURES IS EXPECTED AGAIN ON
WEDNESDAY WITH THE UPPER RIDGE COMING IN...BRINGING 850MB TEMPS UP
TO 1-3C.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
255 PM CST SUN NOV 27 2011
SIMILAR TO YESTERDAY...MODELS AND GFS ENSEMBLES ARE IN PRETTY GOOD
AGREEMENT THROUGH FRIDAY ON THE UPPER AIR PATTERN...THEN BEGIN TO
DIVERGE ON HOW TO HANDLE THE WEEKEND. FIRST FEATURE OF INTEREST IS A
LONG WAVE TROUGH EXTENDING FROM SASKATCHEWAN INTO CALIFORNIA AT 00Z
THURSDAY. MODELS PROG THIS TROUGH TO SPLIT INTO TWO...WITH THE
NORTHERN PORTION CROSSING THE FORECAST AREA THURSDAY NIGHT. AHEAD OF
THE TROUGH...MODELS HAVE BECOME IN BETTER AGREEMENT ALL SHOWING SOME
LIGHT SNOW COMING THROUGH...THOUGH FOR THE 27.12Z ECMWF IT IS A
CHANGE FROM ITS PREVIOUS RUN WHICH HAD NO SNOW DUE TO DRY LOW
LEVELS. THEREFORE...ONLY HAVE 20 PERCENT CHANCES OF SNOW AT THE
MOMENT. LATER FORECASTS MAY NEED HIGHER CHANCES IF MODELS STAY IN
AGREEMENT. DRY AND COLDER CONDITIONS LOOK ON TAP FOR THURSDAY NIGHT
INTO FRIDAY AS 850MB TEMPS DROP TO -8 TO -10C AND SURFACE HIGH
PRESSURE BUILDS IN. THE WEEKEND FEATURES ISSUES REGARDING HANDLING
SHORTWAVES DROPPING DOWN OFF A BUILDING EASTERN PACIFIC RIDGE...AND
IF THESE SHORTWAVES CAN POSSIBLY PHASE WITH THE SOUTHERN END OF THE
LONG WAVE TROUGH THAT GOT CUT-OFF ON THURSDAY. THE 27.12Z GFS AND
SOME OF ITS ENSEMBLES SAY THE CUT-OFF LOW REMAINS...RESULTING IN A
DRY NORTHWEST FLOW PATTERN FOR THE WEEKEND. THE 27.12Z ECMWF AND
EXTRAPOLATION OF THE 27.12Z UKMET/CANADIAN SUGGEST A PHASING OR AT
LEAST THE UPPER LOW GETTING KICKED NORTHEAST TOWARDS THE FORECAST
AREA. HARD TO SAY WHICH ONE IS RIGHT AT THIS MOMENT...BUT SINCE
VERIFICATION WISE THE ECMWF TENDS TO A LITTLE BETTER AND DOES HAVE
SOME CONSISTENCY FROM ITS PREVIOUS RUN...TEND TO LEAN MORE TOWARDS
THE ECMWF/UKMET/CANADIAN CAMP. UNDER THIS SCENARIO...SATURDAY SHOULD
STILL END UP DRY WITH MODERATION AS RETURN FLOW SETS UP BEHIND
FRIDAYS SURFACE RIDGE. ISENTROPIC LIFT/WARM ADVECTION THEN SET UP
FOR SATURDAY NIGHT ACROSS FAR SOUTHERN AREAS OF THE CWA...AND ACROSS
THE REST OF THE FORECAST AREA ON SUNDAY AS THE UPPER LOW APPROACHES.
PLACED IN 20 PERCENT CHANCES AT THE PRESENT TIME...GIVEN THE
UNCERTAINTY PRESENT WITH THE GFS SCENARIO AND SOME OF THE GFS
ENSEMBLES.
&&
.AVIATION...TONIGHT AND MONDAY
532 PM CST SUN NOV 27 2011
FORECAST CHALLENGE CONTINUES TO BE CENTERED ON THE STRATUS AND
WHEN IT WILL FINALLY SCATTER OUT. MODELS NOT HANDLING THE LOW
LEVEL MOISTURE VERY WELL AS IT CONTINUES THE TRENDS OF EARLIER
RUNS IN PUSHING THE CLOUDS OUT TOO SOON. THUS CONFIDENCE NOT HIGH
IN THIS SCENARIO. MVFR CEILINGS WILL CONTINUE AT BOTH TAF
SITES...WITH CEILINGS OF 015-025K FEET. SURFACE RIDGE AXIS DOES
PUSH INTO THE AREA LATE TONIGHT AND 925MB WINDS BEGIN TO SWING
AROUND TO THE SOUTHWEST SHORTLY THEREAFTER. FEEL THIS IS BEST
CHANCE TO PUSH CLOUDS OUT OF THE TAF SITES, THUS SCATTERED OUT THE
STRATUS AT 14Z AT KRST AND 19Z AT KLSE. ONCE STRATUS IS GONE...VFR
CONDITIONS THEN TO PREVAIL THROUGH 00Z TUESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
255 PM CST SUN NOV 27 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
219 PM CST SAT NOV 26 2011
.SHORT TERM...TONIGHT THROUGH TUESDAY
219 PM CST SAT NOV 26 2011
MAIN FORECAST CONCERNS ARE WITH PRECIPITATION TONIGHT AND THEN
TEMPERATURES THROUGH THE REST OF THE SHORT TERM PERIOD.
CURRENTLY AS OF 21Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGES OVER BOTH THE WEST AND EAST COASTS OF THE U.S. AND
TROUGHING IN-BETWEEN FROM MANITOBA SOUTHWARD THROUGH TEXAS. BULK OF
THE ENERGY ASSOCIATED WITH THE UPPER TROUGHING HAS BEEN DROPPING
SOUTH INTO TEXAS PER PRESSURE VALUES ON THE 1.5 PV SURFACE. STILL...
GRADUAL HEIGHT FALLS ON THE EAST SIDE OF THE UPPER TROUGH AND
SHORTWAVES MOVING THROUGH THE SOUTHWEST FLOW...COMBINED WITH LOW
LEVEL MOISTURE TRANSPORT...HELPED BRING THE LIGHT TO MODERATE RAIN
TO MUCH OF THE FORECAST AREA THIS MORNING. THIS PRECIPITATION IS
NOW ONLY AFFECTING THE FAR SOUTHEASTERN PORTION OF THE FORECAST
AREA DUE TO A DRY SLOT IN THE MID TO UPPER LEVELS PUNCHING IN
ELSEWHERE. MEANWHILE...VERY WEAK COLD CONVEYOR BELT AROUND A
1006MB SURFACE LOW IN NORTHEAST WISCONSIN IS REFLECTED BY LIGHT
RADAR RETURNS ACROSS CENTRAL MN INTO NORTHWEST WI. A MIX OF LIGHT
RAIN AND SNOW HAS BEEN REPORTED WITH THESE RADAR RETURNS...THANKS
TO SURFACE TEMPERATURES THAT HAVE BEEN FALLING ON GUSTY NORTHWEST
WINDS. OFF TO THE WEST... EVEN COLDER AIR WAS EVIDENT OVER THE
DAKOTAS INTO MONTANA WHERE 12Z 850MB TEMPS WERE OBSERVED AT -5 TO
-7C. COMPARE THIS TO OBSERVED 4-6C OVER THE AREA AT 12Z TODAY.
SKIES DO CLEAR OUT OVER THE WESTERN DAKOTAS...THOUGH...THANKS TO A
DRY 12Z GLASGOW MT SOUNDING.
TONIGHT AND SUNDAY...UPPER TROUGH OVER THE PLAINS IS FORECAST TO
GRADUALLY TRACK EAST DURING THIS PERIOD...WITH THE 500MB AXIS
SITUATED OVER LA CROSSE AT 12Z SUNDAY AND THEN OVER EASTERN
WISCONSIN AT 00Z MONDAY. SINCE THIS UPPER TROUGH IS COMING THROUGH
POSITIVELY TILTED AND AGAIN MOST OF THE ENERGY DROPPING SOUTH INTO
THE SOUTHERN PLAINS...VERY LITTLE IN THE WAY OF FORCING IS EXPECTED.
MAIN PRECIPITATION LOOKS TO BE THE CURRENT WEAK COLD CONVEYOR BELT
OVER CENTRAL MINNESOTA WHICH SHOULD SLIDE THROUGH MUCH OF THE
FORECAST AREA THIS EVENING. CANNOT RULE OUT A FEW HUNDREDTHS OF
QPF...AS INDICATED BY THE 26.12Z NAM/26.00Z ECMWF...BUT THE
PROBABILITY SEEMS TOO LOW TO GO MORE THAN A 50 PERCENT CHANCE GIVEN
NEARLY DRY 26.09Z SREF MEAN/26.12Z GFS AND GIVEN WEAK APPEARANCE OF
CONVEYOR BELT ON RADAR. PRECIPITATION TYPE WILL BE DETERMINED BY THE
SURFACE TEMPERATURE GIVEN THE WARMEST LAYER AT THE SURFACE...MAKING
IT A RAIN/SNOW SCENARIO. HOWEVER...THERE ARE SOME HINTS OF LOSS OF
ICE DUE TO SOME DRIER AIR IN THE 10000-15000 FT LAYER...WHICH COULD
ALLOW FOR JUST A LITTLE MORE LIQUID VS SNOW. NOT ENOUGH CONFIDENCE
EXISTS TO MENTION ANY FREEZING PRECIPITATION...THOUGH...DUE TO
QUESTION MARKS ON AMOUNT OF PRECIPITATION IN GENERAL AND SURFACE
TEMPERATURES LIKELY TAKING AWHILE TO FALL BELOW FREEZING. ANY
SNOW ACCUMULATION LIKELY TO BE VERY LIGHT IF AT ALL TOO. OVERNIGHT
HOURS THROUGH SUNDAY LOOK MOSTLY DRY AS THE UPPER TROUGH PUSHES
EAST AND SUBSIDENCE COMES IN. CERTAINLY MUCH COOLER WEATHER DURING
THIS PERIOD AS 850MB TEMPS TANK TO -4 TO -8C BY 12Z SUNDAY...ALONG
WITH THE BLUSTERY NORTHWEST WINDS. NOT A WHOLE LOT OF MODIFICATION
EXPECTED TOMORROW WITH CLEARING NOT COMING IN UNTIL LATE AND 850MB
TEMPS STAYING BELOW -2C. IN FACT...ANY CLEARING MAY ONLY OCCUR IN
THE FAR WESTERN FORECAST AREA.
SUNDAY NIGHT THROUGH TUESDAY...QUIET WEATHER LOOKS TO DOMINATE THE
FORECAST AREA DESPITE A FRONTAL PASSAGE LIKELY TO MOVE THROUGH VERY
LATE MONDAY. THINGS WILL BE MORE ACTIVE TO OUR SOUTHEAST AS AN UPPER
LOW FORMS OVER THE SOUTHEASTERN U.S....BUT ANY PRECIPITATION
WRAPPING BACK AROUND THIS UPPER LOW LOOKS TO STAY EAST AND SOUTH OF
CHICAGO. REGARDING THE FRONTAL PASSAGE...A NORTHERN STREAM UPPER
LEVEL TROUGH CURRENTLY OVER THE EASTERN PACIFIC IS FORECAST TO CROSS
THE DAKOTAS ON MONDAY...BRINGING A SURGE OF DOWNSLOPED WARMED AIR
INTO THE FORECAST AREA. 850MB TEMPS ACTUALLY CLIMB UP TO 4-6C BY 00Z
TUESDAY. PROBLEM IS THAT A LOT OF THE WARMING TAKES PLACE ALOFT AND
WE WILL NOT BE ABLE TO MIX UP TO IT...DUE TO THE LOW SUN ANGLE AND
LIGHT WINDS FORECAST. STILL...MIXING UP TO 925MB IS LIKELY WITH FULL
SUNSHINE RESULTING IN HIGHS IN THE UPPER 30S TO LOW 40S. THIS SHOULD
BE A NICE REBOUND AFTER SUNDAY NIGHT LOWS LIKELY IN THE MID TEENS TO
MID 20S...COLDEST IN THE TYPICAL COLD SPOTS. DRY WEATHER EXPECTED
WITH THE FRONTAL PASSAGE DUE TO LACK OF MOISTURE...THEN COOLER
TEMPERATURES COME IN AGAIN AS HIGH PRESSURE BUILDS BACK OVER THE
PLAINS FOR MONDAY NIGHT AND TUESDAY. 850MB TEMPS THIS TIME DO NOT
FALL AS MUCH...ONLY TO -2 TO -4C...SO TUESDAY SHOULD END UP A LITTLE
WARMER THAN SUNDAY. MAY HAVE SOME THICKER HIGH CLOUDS TO DEAL WITH
IN THE MORNING COMING OFF THE SOUTHEASTERN UPPER LOW TO LIMIT
FIXING...BUT THESE LOOK TO START CLEARING OUT IN THE AFTERNOON.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
219 PM CST SAT NOV 26 2011
SIMILAR TO THE SUNDAY NIGHT THROUGH TUESDAY TIME PERIOD...MUCH OF
THE EXTENDED LOOKS QUIET...THOUGH PLENTY OF UNCERTAINTY EXISTS WITH
THE UPPER LEVEL PATTERN HEADING INTO NEXT WEEKEND. LONGWAVE PATTERN
FEATURES UPPER RIDGING BUILDING INTO THE AREA ON WEDNESDAY BETWEEN
THE UPPER LOW LIFTING UP THE EAST COAST AND TROUGHING DIGGING DOWN
THE WEST COAST. SHOULD SEE WARMER TEMPERATURES ON WEDNESDAY
ASSOCIATED WITH THE UPPER RIDGING...THOUGH NOT MUCH ABOVE NORMAL
GIVEN 850MB TEMPS ONLY 2-4C. THIS TROUGHING LOOKS TO SPLIT INTO
TWO...WITH THE NORTHERN STREAM PORTION CROSSING THE FORECAST AREA
THURSDAY NIGHT. MODELS HAVE BEEN SPLIT WHETHER OR NOT FRONTOGENESIS
AND DPVA FORCING AHEAD OF THE NORTHERN STREAM TROUGH CAN PRODUCE
LIGHT SNOW...MOSTLY DUE TO LACK OF MOISTURE WITH IT. CONSENSUS OF
GUIDANCE SUGGESTS JUST A 10-15 PERCENT CHANCE FOR BOTH THURSDAY AND
THURSDAY NIGHT...WHICH RESULTS IN A DRY FORECAST. MORE IMPORTANTLY
IS THE 850MB TEMPS ACCOMPANYING THE TROUGH. MODELS HAVE BEEN
INCONSISTENT INCLUDING RUN TO RUN ON HOW COLD THE AIR IS WITH IT.
CURRENT CONSENSUS IS BETWEEN -8 TO -12C...BUT HAVE SEEN MODELS BOTH
WARMER AND COLDER. THIS SHOULD SET UP TEMPERATURES BELOW NORMAL FOR
FRIDAY AS AN AREA OF HIGH PRESSURE BUILDS IN. HEADING INTO THE
WEEKEND...MODELS ARE IN AGREEMENT OF RIDGING BUILDING UP IN THE
EASTERN PACIFIC. QUESTION IS WHERE SHORTWAVES DIG DOWN TO ON THE
EAST SIDE OF THIS RIDGE. THE 26.12Z GFS AND SOME GFS ENSEMBLE
MEMBERS ALLOW SHORTWAVES TO DIG DOWN INTO THE WESTERN U.S....
RESULTING IN DOWNSTREAM RIDGING OVER THE FORECAST AREA. OTHERS LIKE
THE 26.00Z/26.12Z ECMWF AND OTHER GFS ENSEMBLE MEMBERS DIG THE
SHORTWAVES DOWN MORE OVER THE NORTHERN PLAINS INTO OUR REGION BY
MAINTAINING NORTHWEST FLOW. FOLLOWED A SOMEWHAT OF CONSENSUS
APPROACH WHICH JUST PLACES SOME 10-20 PERCENT CHANCES OVER THE AREA
ON SATURDAY...MAINLY NORTH OF I-90 WITH A SHORTWAVE TROUGH GOING
THROUGH THERE. SLIGHTLY WARMER TEMPERATURES WOULD OCCUR ON SATURDAY
AS WELL WITH WARM ADVECTION ASSOCIATED WITH THE SHORTWAVE TROUGH.
IN SUMMARY...EXTENDED LOOKS AROUND NORMAL ON TEMPERATURES WITH
MAINLY DRY CONDITIONS.
&&
.AVIATION...THIS AFTERNOON THROUGH SUNDAY
1125 AM CST SAT NOV 26 2011
MVFR/IFR CLOUDS WILL PERSIST OVER THE AREA THRU TONIGHT AND WELL
INTO SUNDAY. A COLD FRONT NEAR KEAU-KLSE-KPDC AT 17Z WILL CONTINUE
TO PUSH EAST ACROSS THE AREA THIS AFTERNOON. WINDS WILL INCREASE
FROM THE NORTHWEST FOR THE AFTERNOON AND TONIGHT...SLOWLY SCOURING
OUT THE MVFR/LCL IFR VSBYS IN BR. VSBYS NOT EXPECTED TO IMPROVE TO
VFR UNTIL LATE IN THE AFTERNOON OR EARLY THIS EVENING AS THE SHARPLY
COLDER AIR BEHIND THE FRONT INTERACTS WITH THE MOIST BOUNDARY
LAYER/WET GROUND PRODUCING BR WELL BEHIND THE FRONT. MVFR/IFR CLOUD
DECKS BEHIND THE FRONT AND A LOW IN NORTHEAST WI WRAP ALL THE WAY
BACK INTO THE EASTERN DAKOTAS. WITH THIS MOISTURE BECOMING TRAPPED
UNDER AN INCREASING INVERSION NEAR 900MB TONIGHT...WILL LIKELY HAVE
TO WAIT FOR THE MOISTURE/CLOUDS TO BODILY ADVECT EAST AND OUT OF THE
AREA. PRESENT MODEL TRENDS/TIMING INDICATE THIS WILL NOT OCCUR AT
KRST/KLSE UNTIL EARLY SUN AFTERNOON AT KRST AND LATER SUN AFTERNOON
AT KLSE. PRESSURE GRADIENT WILL REMAIN TIGHT AT THE TAF SITES
TONIGHT/SUN...WITH NORTHWEST WINDS OF 10-20KTS AND GUSTY EXPECTED TO
PREVAIL UNTIL LATER SUN AFTERNOON.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
219 PM CST SAT NOV 26 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1234 AM EST MON NOV 28 2011
.SYNOPSIS...
HIGH PRESSURE REMAINS OFFSHORE TO THE EAST MONDAY WHILE A LOW
PRESSURE SYSTEM TRACKS EAST ACROSS CANADA...DRAGGING A COLD FRONT
THROUGH NEW ENGLAND. A STORM SYSTEM WILL SLOWLY TRACK FROM THE UPPER
OHIO RIVER VALLEY TO THE CANADIAN MARITIME PROVINCES BY THURSDAY
MORNING. WEAK HIGH PRESSURE BUILDS IN THURSDAY AND THURSDAY
NIGHT...FOLLOWED BY A WEAK COLD FRONT ON FRIDAY. HIGH PRESSURE
THEN BUILDS IN FOR THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
0440Z UPDATE...FORECAST ON TRACK...SO ONLY MINOR CHANGES TO NEXT
COUPLE OF HOURS MADE TO THE DATABASE. WITH WEAK WARM ADVECTION AND
INCREASING CLOUDS...LOWS TONIGHT WILL GENERALLY BOTTOM OUT IN THE
LOW TO MID 50S...AND POSSIBLY INTO THE LOWER 40S ACROSS FAR NW
ZONES.
OTHERWISE...WATER VAPOR SHOWS A DEEP LAYERED RIDGE...WITH THE
RIDGE AXIS TO OUR SW...AND GUIDANCE SUGGESTS THE STATUS QUO WILL
MAINTAIN ITSELF THROUGH TONIGHT. THE RESULT IS MINIMAL IF ANY
FORCING...SO HAVE REMOVED ALL PRECIPITATION FROM TONIGHT. UPDATED
POPS ARE CONSISTENT WITH A BLEND OF HRRR HOURLY AND SREF AND NAM
3-HOUR POPS - WEIGHED MORE TOWARDS THE HRRR IN THE FIRST SIX HOURS
OR SO.
STILL APPEAR ON TRACK FOR FOG OR MORE LIKELY STRATUS TO DEVELOP
OVERNIGHT. QUESTION IS WILL THE FOG BECOME DENSE OR...WILL
ULTIMATELY LOW LEVEL STRATUS WIN OUT. FOR NOW BEGINNING TO LEAN
MORE TOWARDS THE STRATUS BASED ON BUFKIT PROFILES...BUT NOT
CONFIDENT ENOUGH TO REMOVE FOG FROM ZONES AT THIS TIME. HOWEVER IF
THE FOG WINDS OUT...WILL LIKELY SEE DENSE FOG...EVEN MORE
WIDESPREAD THEN LAST NIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
THE LIGHT RAIN/DRIZZLE OVER FAR NW ZONES WILL REMAIN POSSIBLE
THROUGH AROUND 16Z BEFORE THINGS DRY UP FOR THE REST OF THE
PERIOD. HIGH PRESSURE REMAINS TO THE EAST...WITH TWO LOW PRESSURE
SYSTEMS BECOMING THE NEXT FOCUS. THE ONE LOW MOVING THROUGH CANADA
WILL DRAG A COLD FRONT THROUGH NORTHERN NEW ENGLAND. CURRENT
GUIDANCE INDICATES THE FRONT WILL REMAIN NORTH OF THE AREA...AND
THUS SHOULDN/T AFFECT THE CWA. THE SECOND LOW FORMS OVER THE
SOUTHEASTERN US MONDAY MORNING AND PUSHES NORTH THROUGH THE
DAY...SETTLING OVER TN AND KY FOR MON NIGHT. THE UPPER LEVEL RIDGE
WILL BEGIN WEAKENING AS WELL MONDAY...AHEAD OF A DEVELOPING UPPER
LEVEL LOW OVER THE MIDWEST.
SOUTHWESTERLY FLOW WILL PERSIST THROUGH MONDAY...WITH THE WINDS
SHIFTING BACK TO A SOUTHERLY FLOW FOR MON NIGHT. SIDED MORE WITH
A GFS/MOS MIX FOR GUIDANCE FOR WINDS DURING THIS PERIOD AS THE NAM
BRINGS THE WINDS AROUND TO THE EAST MUCH QUICKER...BY 12Z TUES
MORNING. CURRENT THINKING WILL BE THE LOW IS SLIGHTLY SLOWER...AND
THE WINDS WILL BE MORE SOUTHEASTERLY BY 12Z TUES MORNING. THE NAM
ALSO WANTS TO HAVE THE HIGH PRESSURE MORE DOMINANT MON NIGHT...SO
SIDED WITH THE WEAKER HIGH WITH THE GFS. WITH THE GFS
TIMING...BROUGHT IN A SLIGHT CHANCE FOR POPS LATE IN THE PERIOD MON
NIGHT FOR THE FAR WESTERN PORTION OF THE CWA. WITH THE LOWER LEVEL
MOISTURE REMAINING ELEVATED...HAVE ALSO INCLUDED PATCHY FOG AROUND
THE CWA FOR MON NIGHT.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
GFS IN GENERAL TOO PROGRESSIVE AS HAS BEEN ITS BIAS OF LATE...SO
USED A NAM/ECMWF/SREF BLEND TUESDAY-WEDNESDAY...THEN FOLLOWED THE
ECMWF WEDNESDAY NIGHT-SUNDAY.
UPPER RIDGE AXIS OVER THE REGION SUPPORTS DAMMING HIGH SIGNATURE
OVER THE REGION TUESDAY INTO TUESDAY NIGHT. THIS WILL HELP TO SERVE
TO IMPEDE PROGRESS OF PRECIPITATION INTO THE REGION AHEAD OF CUTOFF
SYSTEM MOVING INTO THE WEST-CENTRAL APPALACHIANS BY TUESDAY EVENING.
AS A RESULT ONLY BRING POPS UP TO LIKELY OVER WESTERN 1/5 OF CWA AND
JUST BARELY TO CHANCE OVER FAR EASTERN PARTS OF THE CWA BY LATE
AFTERNOON.
STRONG ISENTROPIC LIFT DEVELOPS TUESDAY NIGHT...ALONG WITH 50-60 KT
LOW LEVEL JET IMPACTING REGION...ALLOWING FOR MODERATE TO POSSIBLY
LOCALLY HEAVY RAINFALL TO DEVELOP ACROSS THE TRI-STATE TUESDAY
NIGHT. WITH SHOWALTERS 0 TO -2...HAVE ADDED SLIGHT CHANCE OF THUNDER
TO ALL AREAS EAST OF THE HUDSON PLUS MOST OF NE NJ. CATEGORICAL POPS
THROUGHOUT TUESDAY NIGHT (DEVELOP FROM W TO E).
SHOWERS SHOULD TAPER OFF FROM W TO E MAINLY DURING WEDNESDAY
MORNING. THERE ARE SOME HINTS THAT FAR NW ZONES COULD END UP GETTING
SOME DEFORMATION AXIS PRECIPITATION WEDNESDAY AFTERNOON...BUT TOO
MUCH UNCERTAINTY TO REFLECT THIS IN FORECAST AT THIS TIME. COULD SEE
SOME GUSTY SW-W WINDS BEHIND THE COLD FRONT.
IMPROVING CONDITIONS WEDNESDAY NIGHT AS CLOSED LOW OPENS UP AND
PILLS TO THE NE...WITH WEAK RIDGING BEGINNING TO BUILD IN LATE.
SPLIT FLOW OVER THE EASTERN U.S. THURSDAY/THURSDAY NIGHT...WITH A
SOUTHERN STREAM TROUGH PASSING TO THE S...AND WEAK RIDGING OVER US
EVOLVING INTO SW FLOW ALOFT.
500 HPA TROUGH APPROACHES FRIDAY THEN CROSSES REGION FRIDAY NIGHT.
WITH LIMITED LOW LEVEL MOISTURE TO WORK WITH...GOING WITH A DRY
PASSAGE FOR NOW.
STRONG RIDGE RE-ESTABLISHES ITSELF OVER FLORIDA...WITH ITS RIDGE
AXIS PUSHING UP INTO THE NE STATES SATURDAY...THEN SLIDING OFFSHORE
SUNDAY. THIS SHOULD KEEP THE REGION DRY.
FOR TEMPERATURES...
FOR HIGHS TUESDAY...BLENDED MAV/MET GUIDANCE. HAVE SUSPICIONS THAT
THIS COULD ULTIMATELY END UP BEING ON THE WARM SIDE...WITH
TEMPERATURES STRUGGLING TO GET OUT OF THE 50S WITH THE TRI-STATE
BEING STUCK UNDER LOW CLOUDS/OCCASIONAL DRIZZLE DUE TO ONSHORE
FLOW...BUT STILL NEED TO SEE A FEW MORE THINGS WORK THEMSELVES OUT
BEFORE GOING THIS ROUTE.
FOR LOWS TUESDAY NIGHT...CONTINUED WITH MAV/MET BLEND...WEIGHING
TOWARDS WARMER GUIDANCE AS MAV TRIES TO COOL THINGS OFF TO MUCH AS
IT ENDS PRECIP TOO SOON.
FOR HIGHS WEDNESDAY USED A MEX/MEX ENSEMBLE MEAN BLEND...THEN
CONTINUED TO USE THIS...WITH HPC GUIDANCE BLENDED IN
THURSDAY-SUNDAY. MAIN PLACE HPC GUIDANCE CHANGED THINGS WAS NEXT
WEEKEND WHERE GFS SOLUTION IS NOTABLY COOLER THAN CURRENTLY
PREFERRED ECMWF SOLUTION.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE REMAINS EAST OF THE TERMINALS THROUGH MONDAY THEN
SLIDES EAST AS LOW PRESSURE APPROACHES FROM THE SOUTH.
RADAR WINDS INDICATING WINDS AT 1K FT AROUND 35 KT FROM THE
SOUTHWEST AND LOW LEVEL WINDS OF 35 TO 40 KT REMAIN THROUGH THE
OVERNIGHT AND INTO THE EARLY MORNING...WILL CONTINUE WITH THE LOW
LEVEL WIND SHEAR. WINDS WILL BECOME MORE SOUTHERLY IN THE AFTERNOON
AND THEN SOUTHEASTERLY MONDAY NIGHT.
LOWERING CONFIDENCE IN STRATUS DEVELOPING OVERNIGHT BUT NOT
COMPLETELY UNLIKELY SO WILL INDICATE MVFR CEILINGS POSSIBLE IN A
TEMPO GROUP. FOG ALSO LESS LIKELY AND REMOVED VISIBILITY
RESTRICTIONS.
FLOW BECOMES MORE SOUTHEASTERLY MONDAY NIGHT AND LOW LEVEL MOISTURE
INCREASES. BY LATE EVENING MVFR TO IFR CONDITIONS WILL BECOME LIKELY
ESPECIALLY ALONG THE COAST. STILL A LOT OF UNCERTAINTY IF THE FOG
AND STRATUS WILL DEVELOP MONDAY NIGHT AND HAVE LOW CONFIDENCE.
OUTLOOK FOR 06Z TUESDAY THROUGH FRIDAY...
MONDAY NIGHT...FOG AND STRATUS...MVFR TO IFR CONDITIONS.
TUESDAY-WEDNESDAY...PERIODS OF SUB-VFR CONDITIONS POSSIBLE IN
SHOWERS/FOG.
THURSDAY-FRIDAY...VFR.
&&
.MARINE...
DEVELOPING SOUTHERLY FLOW BRINGS POTENTIAL FOR LOW CLOUDS OR FOG
LATE TONIGHT INTO MONDAY MORNING. IF IT ENDS UP BEING FOG...COULD
END UP NEEDING DENSE FOG ADVISORIES...ESPECIALLY NEAR THE COAST.
SOUTHWESTERLY WINDS WILL PERSIST THROUGH TONIGHT INTO TOMORROW
BEFORE SHIFTING TO A SOUTHEASTERLY FLOW BY TUES MORNING. PRESSURE
GRADIENT IS EXPECTED TO RELAX A BIT TONIGHT...AS HIGH DRIFTS
FURTHER OFFSHORE AND A FRONTAL BOUNDARY REMAINS OVER THE SAINT
LAWRENCE RIVER VALLEY. THIS WILL ALLOW FOR WINDS TO GRADUALLY
DIMINISH OVERNIGHT. WAVEWATCH GUIDANCE BROUGHT 5 FT WAVES TO THE
EDGE OF THE MARINE ZONES...WHILE PRODUCING MAINLY 4 FT OVER THE
REST OF THE OCEAN WATER ZONES. HAVE OPTIONED TO NOT ISSUE A SCA
FOR WAVES FOR TONIGHT. AS THE WINDS CONTINUE TO WEAKEN
MONDAY...EXPECT THE SEAS TO SUBSIDE FOR THE DAY BEFORE INCREASING
AGAIN LATE MON NIGHT AS THE WINDS INCREASE WITH THE APPROACHING
LOW FROM THE SOUTH.
STRENGTHENING EASTERLY FLOW SHOULD BUILD AT LEAST SEAS TO SCA LEVELS
ON THE COASTAL OCEAN WATERS TUESDAY AFTERNOON...AND COULD QUITE
POSSIBLY RESULT IN GUSTS TO 25 KT ON ALL WATERS BY THEN AS WELL.
GUSTY WINDS CONTINUE TUESDAY NIGHT...THOUGH FEEL MARINE LAYER WILL
PREVENT BULK OF 45-55KT 950 HPA JET FROM MIXING DOWN...SO KEPT GUSTS
TO SCA LEVELS. WIND GUSTS TO SCA LEVELS SHOULD CONTINUE ON ALL
WATERS INTO WEDNESDAY EVENING...BUT SEAS SHOULD REMAIN AT SCA LEVELS
ON THE COASTAL OCEAN ZONES ALL NIGHT.
IT IS POSSIBLE THAT SCA LEVEL SEAS COULD PERSIST ON ANZ-350 ON
THURSDAY...OTHERWISE EXPECT SUB-SCA CONDITIONS ON ALL WATERS INTO
FRIDAY.
&&
.HYDROLOGY...
LIGHT RAIN IS POSSIBLE OVER THE HUDSON RIVER VALLEY TONIGHT...WITH
JUST A TRACE EXPECTED. DRY WEATHER WILL PERSIST THROUGH MONDAY FOR
THE REST OF THE CWA. THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL
FROM LATE TUESDAY INTO WEDNESDAY MORNING. FOR NOW FORECASTING
FROM AROUND 1/2 TO 3/4 AN INCH OF RAINFALL WITH LOCALLY HIGHER
AMOUNTS POSSIBLE. THIS MAKES MINOR URBAN/POOR DRAINAGE FLOODING
THE MOST LIKELY SCENARIO...ESPECIALLY IN AREAS RECEIVING LOCALLY
HEAVY RAINFALL DUE TO PASSING ELEVATED CONVECTION.
&&
.CLIMATE...
THE LATEST GUIDANCE INDICATES THAT HIGHS MONDAY WILL NOT REACH
RECORD HIGH TEMPS. HOWEVER...WITH TEMPS STILL FORECASTED IN THE
LOWER 60S...IT MAY STILL BE POSSIBLE FOR ISOLATED LOCATIONS IN AND
AROUND THE NEW YORK CITY METRO AREA TO COME CLOSE. RECORD HIGH
TEMPS WILL ALSO BE APPROACHED ON TUESDAY...WITH HIGHS ONCE AGAIN
BEING FORECASTED IN THE LOWER TO MID 60S.
FOR MONDAY 11/28
EWR 72/1973
BDR 65/2001
NYC *69/1990
LGA 68/1990
JFK 66/2001
ISP 66/1995
* ALSO OCCURRED IN PREVIOUS YEARS
FOR TUESDAY 11/29
EWR 70/1990
BDR 65/1968
NYC 69/1990
LGA 69/1990
JFK 64/1991
ISP 66/1991
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MALOIT/SEARS
NEAR TERM...MALOIT/MPS
SHORT TERM...SEARS
LONG TERM...MALOIT
AVIATION...MET
MARINE...MALOIT/SEARS
HYDROLOGY...SEARS
CLIMATE...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1139 PM EST SUN NOV 27 2011
.SYNOPSIS...
HIGH PRESSURE REMAINS OFFSHORE TO THE EAST MONDAY WHILE A LOW
PRESSURE SYSTEM TRACKS EAST ACROSS CANADA...DRAGGING A COLD FRONT
THROUGH NEW ENGLAND. A STORM SYSTEM WILL SLOWLY TRACK FROM THE UPPER
OHIO RIVER VALLEY TO THE CANADIAN MARITIME PROVINCES BY THURSDAY
MORNING. WEAK HIGH PRESSURE BUILDS IN THURSDAY AND THURSDAY
NIGHT...FOLLOWED BY A WEAK COLD FRONT ON FRIDAY. HIGH PRESSURE
THEN BUILDS IN FOR THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
0440Z UPDATE...FORECAST ON TRACK...SO ONLY MINOR CHANGES TO NEXT
COUPLE OF HOURS MADE TO THE DATABASE. WITH WEAK WARM ADVECTION AND
INCREASING CLOUDS...LOWS TONIGHT WILL GENERALLY BOTTOM OUT IN THE
LOW TO MID 50S...AND POSSIBLY INTO THE LOWER 40S ACROSS FAR NW
ZONES.
OTHERWISE...WATER VAPOR SHOWS A DEEP LAYERED RIDGE...WITH THE
RIDGE AXIS TO OUR SW...AND GUIDANCE SUGGESTS THE STATUS QUO WILL
MAINTAIN ITSELF THROUGH TONIGHT. THE RESULT IS MINIMAL IF ANY
FORCING...SO HAVE REMOVED ALL PRECIPITATION FROM TONIGHT. UPDATED
POPS ARE CONSISTENT WITH A BLEND OF HRRR HOURLY AND SREF AND NAM
3-HOUR POPS - WEIGHED MORE TOWARDS THE HRRR IN THE FIRST SIX HOURS
OR SO.
STILL APPEAR ON TRACK FOR FOG OR MORE LIKELY STRATUS TO DEVELOP
OVERNIGHT. QUESTION IS WILL THE FOG BECOME DENSE OR...WILL
ULTIMATELY LOW LEVEL STRATUS WIN OUT. FOR NOW BEGINNING TO LEAN
MORE TOWARDS THE STRATUS BASED ON BUFKIT PROFILES...BUT NOT
CONFIDENT ENOUGH TO REMOVE FOG FROM ZONES AT THIS TIME. HOWEVER IF
THE FOG WINDS OUT...WILL LIKELY SEE DENSE FOG...EVEN MORE
WIDESPREAD THEN LAST NIGHT.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
THE LIGHT RAIN/DRIZZLE OVER FAR NW ZONES WILL REMAIN POSSIBLE
THROUGH AROUND 16Z BEFORE THINGS DRY UP FOR THE REST OF THE
PERIOD. HIGH PRESSURE REMAINS TO THE EAST...WITH TWO LOW PRESSURE
SYSTEMS BECOMING THE NEXT FOCUS. THE ONE LOW MOVING THROUGH CANADA
WILL DRAG A COLD FRONT THROUGH NORTHERN NEW ENGLAND. CURRENT
GUIDANCE INDICATES THE FRONT WILL REMAIN NORTH OF THE AREA...AND
THUS SHOULDN/T AFFECT THE CWA. THE SECOND LOW FORMS OVER THE
SOUTHEASTERN US MONDAY MORNING AND PUSHES NORTH THROUGH THE
DAY...SETTLING OVER TN AND KY FOR MON NIGHT. THE UPPER LEVEL RIDGE
WILL BEGIN WEAKENING AS WELL MONDAY...AHEAD OF A DEVELOPING UPPER
LEVEL LOW OVER THE MIDWEST.
SOUTHWESTERLY FLOW WILL PERSIST THROUGH MONDAY...WITH THE WINDS
SHIFTING BACK TO A SOUTHERLY FLOW FOR MON NIGHT. SIDED MORE WITH
A GFS/MOS MIX FOR GUIDANCE FOR WINDS DURING THIS PERIOD AS THE NAM
BRINGS THE WINDS AROUND TO THE EAST MUCH QUICKER...BY 12Z TUES
MORNING. CURRENT THINKING WILL BE THE LOW IS SLIGHTLY SLOWER...AND
THE WINDS WILL BE MORE SOUTHEASTERLY BY 12Z TUES MORNING. THE NAM
ALSO WANTS TO HAVE THE HIGH PRESSURE MORE DOMINANT MON NIGHT...SO
SIDED WITH THE WEAKER HIGH WITH THE GFS. WITH THE GFS
TIMING...BROUGHT IN A SLIGHT CHANCE FOR POPS LATE IN THE PERIOD MON
NIGHT FOR THE FAR WESTERN PORTION OF THE CWA. WITH THE LOWER LEVEL
MOISTURE REMAINING ELEVATED...HAVE ALSO INCLUDED PATCHY FOG AROUND
THE CWA FOR MON NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
GFS IN GENERAL TOO PROGRESSIVE AS HAS BEEN ITS BIAS OF LATE...SO
USED A NAM/ECMWF/SREF BLEND TUESDAY-WEDNESDAY...THEN FOLLOWED THE
ECMWF WEDNESDAY NIGHT-SUNDAY.
UPPER RIDGE AXIS OVER THE REGION SUPPORTS DAMMING HIGH SIGNATURE
OVER THE REGION TUESDAY INTO TUESDAY NIGHT. THIS WILL HELP TO SERVE
TO IMPEDE PROGRESS OF PRECIPITATION INTO THE REGION AHEAD OF CUTOFF
SYSTEM MOVING INTO THE WEST-CENTRAL APPALACHIANS BY TUESDAY EVENING.
AS A RESULT ONLY BRING POPS UP TO LIKELY OVER WESTERN 1/5 OF CWA AND
JUST BARELY TO CHANCE OVER FAR EASTERN PARTS OF THE CWA BY LATE
AFTERNOON.
STRONG ISENTROPIC LIFT DEVELOPS TUESDAY NIGHT...ALONG WITH 50-60 KT
LOW LEVEL JET IMPACTING REGION...ALLOWING FOR MODERATE TO POSSIBLY
LOCALLY HEAVY RAINFALL TO DEVELOP ACROSS THE TRI-STATE TUESDAY
NIGHT. WITH SHOWALTERS 0 TO -2...HAVE ADDED SLIGHT CHANCE OF THUNDER
TO ALL AREAS EAST OF THE HUDSON PLUS MOST OF NE NJ. CATEGORICAL POPS
THROUGHOUT TUESDAY NIGHT (DEVELOP FROM W TO E).
SHOWERS SHOULD TAPER OFF FROM W TO E MAINLY DURING WEDNESDAY
MORNING. THERE ARE SOME HINTS THAT FAR NW ZONES COULD END UP GETTING
SOME DEFORMATION AXIS PRECIPITATION WEDNESDAY AFTERNOON...BUT TOO
MUCH UNCERTAINTY TO REFLECT THIS IN FORECAST AT THIS TIME. COULD SEE
SOME GUSTY SW-W WINDS BEHIND THE COLD FRONT.
IMPROVING CONDITIONS WEDNESDAY NIGHT AS CLOSED LOW OPENS UP AND
PILLS TO THE NE...WITH WEAK RIDGING BEGINNING TO BUILD IN LATE.
SPLIT FLOW OVER THE EASTERN U.S. THURSDAY/THURSDAY NIGHT...WITH A
SOUTHERN STREAM TROUGH PASSING TO THE S...AND WEAK RIDGING OVER US
EVOLVING INTO SW FLOW ALOFT.
500 HPA TROUGH APPROACHES FRIDAY THEN CROSSES REGION FRIDAY NIGHT.
WITH LIMITED LOW LEVEL MOISTURE TO WORK WITH...GOING WITH A DRY
PASSAGE FOR NOW.
STRONG RIDGE RE-ESTABLISHES ITSELF OVER FLORIDA...WITH ITS RIDGE
AXIS PUSHING UP INTO THE NE STATES SATURDAY...THEN SLIDING OFFSHORE
SUNDAY. THIS SHOULD KEEP THE REGION DRY.
FOR TEMPERATURES...
FOR HIGHS TUESDAY...BLENDED MAV/MET GUIDANCE. HAVE SUSPICIONS THAT
THIS COULD ULTIMATELY END UP BEING ON THE WARM SIDE...WITH
TEMPERATURES STRUGGLING TO GET OUT OF THE 50S WITH THE TRI-STATE
BEING STUCK UNDER LOW CLOUDS/OCCASIONAL DRIZZLE DUE TO ONSHORE
FLOW...BUT STILL NEED TO SEE A FEW MORE THINGS WORK THEMSELVES OUT
BEFORE GOING THIS ROUTE.
FOR LOWS TUESDAY NIGHT...CONTINUED WITH MAV/MET BLEND...WEIGHING
TOWARDS WARMER GUIDANCE AS MAV TRIES TO COOL THINGS OFF TO MUCH AS
IT ENDS PRECIP TOO SOON.
FOR HIGHS WEDNESDAY USED A MEX/MEX ENSEMBLE MEAN BLEND...THEN
CONTINUED TO USE THIS...WITH HPC GUIDANCE BLENDED IN
THURSDAY-SUNDAY. MAIN PLACE HPC GUIDANCE CHANGED THINGS WAS NEXT
WEEKEND WHERE GFS SOLUTION IS NOTABLY COOLER THAN CURRENTLY
PREFERRED ECMWF SOLUTION.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
HIGH PRESSURE REMAINS EAST OF THE TERMINALS WITH A DEEP SOUTHERLY
FLOW. CONDITIONS START OFF AT VFR...HOWEVER STRATUS IS LIKELY TO
DEVELOP LATE THIS EVENING INTO THE OVERNIGHT TOWARD 07Z...WITH
MVFR CEILINGS. DO NOT HAVE HIGH CONFIDENCE IN IFR CEILINGS
DEVELOPING...AND MODERATE IF ANY STRATUS DEVELOPS. WITH THE UPDATE
REMOVED IFR CEILINGS FROM THE TERMINALS. IF VISIBILITIES LOWER
WILL BE BRIEFLY TO MVFR. CONFIDENCE FOR FOG DEVELOPMENT LOWER
THAN FOR STRATUS.
IMPROVEMENT BACK TO VFR WILL OCCUR AROUND MID MORNING...13Z TO 15Z.
OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
MONDAY NIGHT...FOG AND STRATUS DEVELOPING WITH MVFR TO IFR
CONDITIONS.
TUESDAY-WEDNESDAY...PERIODS OF SUB-VFR CONDITIONS POSSIBLE IN
SHOWERS/FOG.
THURSDAY-FRIDAY...VFR.
&&
.MARINE...
DEVELOPING SOUTHERLY FLOW BRINGS POTENTIAL FOR LOW CLOUDS OR FOG
LATE TONIGHT INTO MONDAY MORNING. IF IT ENDS UP BEING FOG...COULD
END UP NEEDING DENSE FOG ADVISORIES...ESPECIALLY NEAR THE COAST.
SOUTHWESTERLY WINDS WILL PERSIST THROUGH TONIGHT INTO TOMORROW
BEFORE SHIFTING TO A SOUTHEASTERLY FLOW BY TUES MORNING. PRESSURE
GRADIENT IS EXPECTED TO RELAX A BIT TONIGHT...AS HIGH DRIFTS
FURTHER OFFSHORE AND A FRONTAL BOUNDARY REMAINS OVER THE SAINT
LAWRENCE RIVER VALLEY. THIS WILL ALLOW FOR WINDS TO GRADUALLY
DIMINISH OVERNIGHT. WAVEWATCH GUIDANCE BROUGHT 5 FT WAVES TO THE
EDGE OF THE MARINE ZONES...WHILE PRODUCING MAINLY 4 FT OVER THE
REST OF THE OCEAN WATER ZONES. HAVE OPTIONED TO NOT ISSUE A SCA
FOR WAVES FOR TONIGHT. AS THE WINDS CONTINUE TO WEAKEN
MONDAY...EXPECT THE SEAS TO SUBSIDE FOR THE DAY BEFORE INCREASING
AGAIN LATE MON NIGHT AS THE WINDS INCREASE WITH THE APPROACHING
LOW FROM THE SOUTH.
STRENGTHENING EASTERLY FLOW SHOULD BUILD AT LEAST SEAS TO SCA LEVELS
ON THE COASTAL OCEAN WATERS TUESDAY AFTERNOON...AND COULD QUITE
POSSIBLY RESULT IN GUSTS TO 25 KT ON ALL WATERS BY THEN AS WELL.
GUSTY WINDS CONTINUE TUESDAY NIGHT...THOUGH FEEL MARINE LAYER WILL
PREVENT BULK OF 45-55KT 950 HPA JET FROM MIXING DOWN...SO KEPT GUSTS
TO SCA LEVELS. WIND GUSTS TO SCA LEVELS SHOULD CONTINUE ON ALL
WATERS INTO WEDNESDAY EVENING...BUT SEAS SHOULD REMAIN AT SCA LEVELS
ON THE COASTAL OCEAN ZONES ALL NIGHT.
IT IS POSSIBLE THAT SCA LEVEL SEAS COULD PERSIST ON ANZ-350 ON
THURSDAY...OTHERWISE EXPECT SUB-SCA CONDITIONS ON ALL WATERS INTO
FRIDAY.
&&
.HYDROLOGY...
LIGHT RAIN IS POSSIBLE OVER THE HUDSON RIVER VALLEY TONIGHT...WITH
JUST A TRACE EXPECTED. DRY WEATHER WILL PERSIST THROUGH MONDAY FOR
THE REST OF THE CWA. THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL
FROM LATE TUESDAY INTO WEDNESDAY MORNING. FOR NOW FORECASTING
FROM AROUND 1/2 TO 3/4 AN INCH OF RAINFALL WITH LOCALLY HIGHER
AMOUNTS POSSIBLE. THIS MAKES MINOR URBAN/POOR DRAINAGE FLOODING
THE MOST LIKELY SCENARIO...ESPECIALLY IN AREAS RECEIVING LOCALLY
HEAVY RAINFALL DUE TO PASSING ELEVATED CONVECTION.
&&
.CLIMATE...
THE LATEST GUIDANCE INDICATES THAT HIGHS MONDAY WILL NOT REACH
RECORD HIGH TEMPS. HOWEVER...WITH TEMPS STILL FORECASTED IN THE
LOWER 60S...IT MAY STILL BE POSSIBLE FOR ISOLATED LOCATIONS IN AND
AROUND THE NEW YORK CITY METRO AREA TO COME CLOSE. RECORD HIGH
TEMPS WILL ALSO BE APPROACHED ON TUESDAY...WITH HIGHS ONCE AGAIN
BEING FORECASTED IN THE LOWER TO MID 60S.
FOR MONDAY 11/28
EWR 72/1973
BDR 65/2001
NYC *69/1990
LGA 68/1990
JFK 66/2001
ISP 66/1995
* ALSO OCCURRED IN PREVIOUS YEARS
FOR TUESDAY 11/29
EWR 70/1990
BDR 65/1968
NYC 69/1990
LGA 69/1990
JFK 64/1991
ISP 66/1991
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MALOIT/SEARS
NEAR TERM...MALOIT/MPS
SHORT TERM...SEARS
LONG TERM...MALOIT
AVIATION...MET
MARINE...MALOIT/SEARS
HYDROLOGY...SEARS
CLIMATE...
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1123 PM CST SUN NOV 27 2011
.UPDATE 28/06Z AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
PRIMARY CONCERN REMAINS LOW CLOUD TRENDS. MODELS HAVE HAD A POOR
TIME INITIALIZING AND RESOLVING STRATUS...BUT LATEST RUC SEEMS TO
HAVE THE BEST HANDLE ON THINGS BEING MORE PERSISTENT. THIS
GENERALLY AGREES WITH EXTRAPOLATION NUDGING CLEARING LINE SLOWLY
EASTWARD INTO CENTRAL IA TOWARD MIDNIGHT AND SUGGESTING CLEARING TO
OUR ERN FORECAST AREA BY MORNING BASED ON FURTHER EXTRAPOLATION.
LOW CONFIDENCE IN THESE TRENDS WILL ALSO SPILL OVER INTO MIN TEMPS.
HAVE GENERALLY FOLLOWED GUIDANCE WEST WHERE AIRMASS IS ADEQUATELY
REPRESENTED BY MODELS. HOWEVER NUDGED TEMPS UP ABOVE EVEN THE
WARMEST GUIDANCE EAST WHERE PROLONGED CLOUD COVER IS ANTICIPATED.
CLEARING PROGRESSION WILL MAKE ALL THE DIFFERENCE...SO EXPECT
CONSIDERABLE GRADIENT IN MIN TEMPS.
.LONG TERM /TONIGHT THROUGH SUNDAY/...
FAIRLY BENIGN MID/LONG RANGE WITH LITTLE IN THE WAY OF PRECIPITATION
CHANCES UNTIL THE NEXT WEEKEND. NEXT WEATHER SYSTEM TO IMPACT IOWA
WILL BE A POSITIVELY TILTED SHORTWAVE MOVING ONSHORE IN THE PACIFIC
NORTHWEST AT THIS TIME. THE BRUNT OF THE SHORTWAVE ENERGY
ASSOCIATED WITH THE WAVE WILL PASS TO THE EAST WELL NORTH OF IOWA.
THE SOUTHERN PART OF THE SHORTWAVE SHOULD MERGE WITH LARGE UPPER LOW
OVER THE OHIO VALLEY BY 18Z TUESDAY. THE COLD FRONT ASSOCIATED WITH
THE SHORTWAVE SHOULD CROSS IOWA MONDAY NIGHT. ONLY LIMITED FORCING
AND MOISTURE SHOULD KEEP THE SENSIBLE WEATHER IMPACT LIMITED TO
INCREASED WINDS...CLOUDS AND MODEST COOLING BUT NO PRECIPITATION.
ON MONDAY...THERE SHOULD BE VERY LITTLE BOUNDARY LAYER FLOW WITH THE
CENTER OF A WEAK SURFACE HIGH PRESSURE SYSTEM IN THE AREA. MODEL
SOUNDINGS SHOW A VERY STRONG INVERSION WITH MINIMAL MIXING.
THEREFORE...EXPECT COOL TEMPERATURES WITH LIGHT SURFACE WINDS.
FOR THURSDAY AND BEYOND INTO NEXT WEEKEND...THE GFS AND ECMWF ONCE
AGAIN DIVERGE IN THEIR SOLUTIONS OF THE WEATHER OVER THE UPPER
MIDWEST. THE ECMWF LIFTS OUT AND WEAKENS THE SOUTHWEST UNITED
STATES UPPER LOW INTO THE PLAINS BY NEXT SATURDAY EVENING. THIS
WILL BRING THE NEXT CHANCE OF PRECIPITATION TO IOWA. IT IS FAR TO
EARLY TO DETERMINE THE EXTENT OF THE PRECIPITATION CHANCES OR THE
PRECIPITATION TYPE. FOR NOW...INTRODUCED SMALL POPS SATURDAY NIGHT
INTO SUNDAY.
&&
.AVIATION DISCUSSION...28/06Z
ST SHIELD CONTINUES TO SLOW...THOUGH SOME EROSION HAS TAKEN PLACE
OVER SOUTH CENTRAL MN AND MAY HELP TO ERODE PORTIONS OF NORTHERN
IOWA SHIELD. WILL NOT BANK ON THIS...HOWEVER. ELSEWHERE...BACK EDGE
HAS COME TO A STANDSTILL AS LIGHT NORTH NORTHEAST WINDS PREVAIL FOR
NOW. EXPECT SOME EASTWARD PROGRESS OVERNIGHT...BUT HAVE SLOWED
CLEARING EVEN MORE FROM PREVIOUS UPDATE WITH EASTERN TAF SITES NOW
CLEARING CLOSER TO 17 TO 18Z...WHILE WEST AND CENTRAL SITES SHOULD
CLEAR BETWEEN 06 AND 08Z. H700 RIDGE INCREASING ALOFT AND
ANTICYCLONIC CURVATURE SHOULD...IN THEORY...HELP THE PROCESS ALONG
OVERNIGHT INTO THE EARLY MORNING HOURS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SMALL
AVIATION...REV
LONG TERM...JOHNSON
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
238 AM EST MON NOV 28 2011
.SYNOPSIS...
SLOW MOVING LOW PRESSURE WILL BRING PERIODS OF RAIN FOR THE FIRST
HALF OF THE WEEK. MILD TEMPERATURES EARLY IN THE WEEK WILL COOL
SIGNIFICANTLY BY WEDNESDAY...WITH RESIDUAL RAIN SHOWERS CHANGING
TO SNOW.
&&
.NEAR TERM /THROUGH TONIGHT/...
A LARGE UPPER LEVEL TROUGH WILL CONTINUE TO DIG SOUTH ACROSS
THE MISSISSIPPI VALLEY TODAY. WITH THE NORTHERN BRANCH UPPER LOW
EJECTING NORTHEAST INTO THE CANADIAN MARITIMES...THIS WILL RESULT
IN SPLIT FLOW DEVELOPING ACROSS THE UPPER OHIO VALLEY LATER TODAY.
HENCE...PRECIP COVERAGE WILL BEGIN TO DIMINISH THIS MORNING...WITH
ISOLATED TO SCATTERED SHOWERS REMAINING FOR THIS AFTN INTO THE
EVENING. BY LATER TONIGHT...THE UPPER TROUGH ACROSS THE MS
VALLEY WILL PULL NORTHWARD...BRINGING AN INCREASING COVERAGE OF
SHOWERS BACK INTO THE FCST. AHEAD OF THE UPPER TROUGH...WARM
AIR WILL CONTINUE TO SURGE NORTHWARD...AND WITH PERHAPS SOME CLOUD
BREAKS IN THE AFTN...EXPECT HIGH TEMPERATURES IN THE UPPER 50S
TO LOWER 60S...WITH SOME MID 60S POSSIBLE NEAR/SOUTH OF THE
MASON DIXON. WITH WARM AIR REMAINING ACROSS THE AREA TNGT...ALONG
WITH CLOUDS...EXPECT VERY MILD LOW TEMPERATURES IN THE LOWER TO
MID 50S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
THE UPPER LOW PRESSURE SYSTEM IS PROGGED TO MIGRATE NORTH INTO
THE REGION TUESDAY INTO TUESDAY NIGHT...EJECTING NORTHEAST
WEDNESDAY. WIDESPREAD SHOWERS WILL PREVAIL FOR MOST OF TUESDAY
WITH A GRADUAL DECREASING TREND TUESDAY NIGHT...AND MAINLY
SCATTERED PRECIP WEDNESDAY. EXPECTED POSITIONING OF OCCLUDING
SURFACE FRONT...FORECAST TRACK OF THE LOW...AND MID LEVEL DRY
PUNCH MAY LIMIT PRECIP TOTALS...BUT WITH AMOUNTS FORECAST IN
THE 1 INCH RANGE...ON TOP OF SUNDAY/MONDAY RAINFALL...WILL
CONTINUE MENTION OF STREAM RISES IN THE HAZARDOUS WEATHER OUTLOOK.
AS THE UPPER LOW MOVES NORTHEAST OF THE AREA...MUCH COLDER AIR
WILL ENTER THE REGION...WITH PRECIP CHANGING OVER TO SNOW FOR MOST
AREAS WEDNESDAY. WITH TEMPERATURES REMAINING ABOVE FREEZING UNTIL
WEDNESDAY NIGHT...AND EXPECTED LIGHT SNOWFALL RATES...DO NOT
EXPECT SIGNIFICANT ACCUMULATION...WITH PERHAPS AN INCH OR SO ON
THE RIDGES AND ALONG THE I-80 CORRIDOR.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BUILD ACROSS THE AREA THURSDAY FOR DRY BUT
CHILLY CONDITIONS. MODELS HAVE BEEN CONSISTENT WITH A WEAK COLD
FRONT CLIPPING THE AREA LATE FRIDAY/FRIDAY NIGHT. WITH LIMITED
MOISTURE...WILL USE LOW END CHANCE POPS. DRY AND CHILLY CONDITIONS
ARE EXPECTED FOR THE WEEKEND.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
PER RECENT SURFACE AND RADAR DATA ALONG WITH HRRR AND NAM MODEL
OUTPUT, EXPECT FRONTAL RAIN BAND, NORTHEAST OF KENTUCKY LOW PRESSURE
CENTER TO REMAIN OVER MUCH OF THE UPPER OHIO VALLEY THROUGH 15Z,
BEFORE PIVOTING NORTHWESTWARD THE REST OF TODAY. MVFR CONDITIONS
WILL BE PREVALENT WITH THE RAIN BAND, BUT THERE CAN BE PERIODS OF
IFR 09Z-14Z. AS RAIN BAND EXITS NORTHWEST, EXPECT VFR TO BECOME
PREVALENT THIS AFTERNOON, EXCEPT FOR MAYBE KZZV AND KFKL.
OUTLOOK...MONDAY NIGHT THROUGH FRIDAY....
NORTHEASTWARD MOVING COLD FRONTAL BAND OF RAIN WILL PROVIDE RENEWED
RESTRICTIONS LATE TUESDAY MORNING INTO TUESDAY NIGHT. POST SYSTEM
WRAP AROUND SHOWERS OF RAIN AND SNOW MAY CAUSE ADDITIONAL SHORT
PERIODS OF RESTRICTIONS WEDNESDAY. AFTER VFR UNDER HIGH PRESSURE
THURSDAY, COLD FRONTAL SHOWERS OF RAIN OR SNOW MAY PROVIDE
RESTRICTIONS FRIDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
101 AM EST MON NOV 28 2011
.SYNOPSIS...
A SLOW MOVING LOW PRESSURE SYSTEM WILL BRING PERIODS OF RAIN FOR THE
FIRST HALF OF THE WEEK. MILD TEMPERATURES EARLY IN THE WEEK WILL
COOL SIGNIFICANTLY BY WEDNESDAY AND CHANGE RESIDUAL RAIN SHOWERS TO
SNOW.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
WITH A TROUGH DIGGING ACROSS THE MISSISSIPPI VALLEY...RAIN WILL
CONTINUE THROUGH THE OVERNIGHT...WITH CATEGORICAL COVERAGE FROM
A DUJ/PIT/MGW LINE WESTWARD. FURTHER EAST...WILL USE CHANCE POPS
TO LBE...WITH LITTLE/NO PRECIP FOR THE WV/MD RIDGES. NEAR
STEADY TEMPERATURES IN THE UPPER 40S TO LOWER 50 WILL PREVAIL.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY/...
PERIODIC SHOWERS CAN BE EXPECTED INTO MID WEEK AS THE MATURING LOW
DIGS NEWD. RAINFALL TOTALS THROUGH TUESDAY NIGHT WERE CONSERVATIVELY
FORECAST AT APPROXIMATELY AN INCH FOR MOST AREAS...BUT INCREASED
TO NEAR 2 INCHES ALONG THE INTERSTATE 77 CORRIDOR IN RESPONSE TO
EXPECTED POSITIONING OF OCCLUDING FRONT/FORECAST TRACK OF THE LOW.
MID LEVEL DRY PUNCH AND SHIFTING FRONTOGENESIS SLOT SHOULD LIMIT
TOTALS...BUT MENTION OF STREAM RISES WAS NEVERTHELESS INCLUDED IN
THE HAZARDOUS WEATHER OUTLOOK FOR THIS PERIOD.
SHORT TERM TEMPERATURES WILL REMAIN MILD UNTIL THE SYSTEMS COLD
FRONT SWEEPS THE REGION ON TUESDAY NIGHT AND CHANGES RESIDUAL PCPN
TO SNOW SHOWERS FOR WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
BY WEDNESDAY EVENING NORTHERLY FLOW BEHIND EXITING STORM IN NEW
ENGLAND MAY KEEP A FEW SHOWERS/FLURRIES OVER REGION EARLY. HIGH
PRESSURE WILL BUILD NORTHEAST TO WV BY THURSDAY MORNING BRINGING
DRIER AIR AND SUNSHINE. MODELS CONSISTENT WITH COLD MOVING
SOUTHEAST FROM GREAT LAKES ON FRIDAY WITH LIMITED MOISTURE. CHANCE
OF SHOWERS FROM MID DAY FRIDAY ON. BY SATURDAY BROAD WESTERLY FLOW
WILL BRING COLDER TEMPERATURES WITH LOWS IN THE 20S AND HIGHS IN THE
30S AND LITTLE THREAT OF PRECIPITATION FOR THE WEEKEND.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
PER RECENT SURFACE AND RADAR DATA COUPLED WITH HRRR AND NAM MODEL
OUTPUT, EXPECT FRONTAL RAIN BAND NORTHEAST OF KENTUCKY LOW
PRESSURE CENTER TO MOVE INTO EASTERN PARTS OF THE UPPER OHIO
VALLEY THROUGH 15Z, BEFORE PIVOTING NORTHWESTWARD THE REST OF
TODAY. EXPECT MVFR CONDITIONS TO BE PREVALENT WITH THE RAIN BAND,
BUT THERE CAN BE PERIODS OF IFR 09Z-14Z. AS RAIN BAND EXITS
NORTHWEST, EXPECT VFR TO BECOME PREVALENT THIS AFTERNOON, EXCEPT
FOR MAYBE KZZV AND KFKL.
OUTLOOK...MONDAY NIGHT THROUGH FRIDAY....
NORTHEASTWARD MOVING COLD FRONTAL BAND OF RAIN WILL PROVIDE
RESTRICTIONS LATE TUESDAY MORNING INTO TUESDAY NIGHT. POST SYSTEM
WRAP AROUND SHOWERS OF RAIN AND SNOW MAY CAUSE ADDITIONAL SHORT
PERIODS OF RESTRICTIONS WEDNESDAY. AFTER VFR UNDER HIGH PRESSURE
THURSDAY, COLD FRONTAL SHOWERS OF RAIN OR SNOW MAY PROVIDE
RESTRICTIONS FRIDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1049 PM CST SUN NOV 27 2011
.DISCUSSION...
/ISSUED 346 PM CST SUN NOV 27 2011/
SUMMARY...LARGELY DRY FORECAST WITH ONLY SMALL POPS IN THE
FORECAST FOR THURSDAY AND NEXT SUNDAY. THREE COLD FRONTS MOVE
THROUGH OVER THE NEXT 7 DAYS...MONDAY NIGHT...WEDNESDAY
NIGHT...AND SATURDAY NIGHT. SLIGHTLY ABOVE NORMAL TEMPS ARE
EXPECTED AHEAD OF THESE BOUNDARIES MONDAY...WEDNESDAY AND
SATURDAY. NEAR NORMAL OR SLIGHTLY BELOW NORMALS TEMPS ARE
EXPECTED BEHIND THE FRONTAL PASSAGES ON TUESDAY...
THURSDAY...FRIDAY AND SUNDAY.
TONIGHT AND TOMORROW...TRICKY TEMP FORECAST: STRATUS DECK HAS BEEN
VERY SLOW TO CLEAR TODAY AND CONTINUES MOVING TO THE EAST AT JUST
7KTS. WITHIN THE LAST HOUR OR SO...WE`RE FINALLY SEEING SOME
THINNING OF THE DECK IN MN. THIS MIGHT BE A SIGN THAT THE CLEARING
IS A BIT FASTER THAN WHAT`S IN THE FORECAST FOR TONIGHT.
HOWEVER...WE WILL LOSE OUR SUN HERE IN THE NEXT COUPLE HOURS...SO
KEPT THE SLOW CLEARING TREND IN THE FORECAST TONIGHT. MIGHT HAVE
TO WAIT FOR THE RIDGE AXIS TO PASS OVERHEAD...WHICH WOULD MATCH UP
FAIRLY WELL WITH THE 925MB RH OFF THE RUC THIS EVENING. THE CLOUDS
WILL OBVIOUSLY HAVE LARGE IMPACT ON THE TEMPERATURES TONIGHT. KEPT
WEST CENTRAL WI IN THE MID 20S AND EVEN LEFT MOST OF THE METRO IN
THE LOWER TO MID 20S. AREAS THAT GET AT LEAST 3-4 HOURS OF CLEAR
SKIES TOMORROW MORNING...WILL LIKELY GET INTO THE TEENS FOR LOWS.
OTHERWISE...THE MERCURY WILL BE HEADING THE OTHER WAY TOMORROW WITH
WARM AIR ADVECTION KICKING IN BETWEEN 06-12Z TONIGHT. SOUTHWEST
WINDS WITH MIXING UP TO 975-925MB OFF THE FORECAST SOUNDINGS WOULD
GIVE US LOW TO MID 40S ALMOST EVERYWHERE TOMORROW. IN
FACT...DOWNSLOPING OFF THE BUFFALO RIDGE IN WESTERN MN SHOULD
YIELD 50S FOR HIGHS. COLD FRONT PASSES THROUGH FROM NW TO SE LATE
TOMORROW AFTERNOON AND TOMORROW EVENING. MIGHT BE A MID DECK OF
CLOUDS WITH THE FRONT BUT NO PRECIPITATION IS EXPECTED.
TUESDAY THROUGH THURSDAY...-4 TO -6 C AT 850MB INDICATING A COOL
DOWN FOR TUESDAY BEHIND THE FRONT BUT CERTAINLY NOTHING OUT OF THE
ORDINARY. THE COOL DOWN WILL BE BRIEF WITH 1000-500MB THICKNESS
ALREADY CLIMBING BETWEEN 540M-546M EARLY WEDNESDAY. ANOTHER FRONT
MOVES THROUGH WEDNESDAY NIGHT AND WITH THIS BOUNDARY THERE MIGHT
BE JUST ENOUGH FORCING AND MOISTURE TO SHAKE OUT A FEW SNOW FLAKES
IN THE STRATO CUMULUS IN THE WAKE OF THE FRONT ON THURSDAY. BOTH
THE 27.12Z GFS/ECMWF HAVE A FEW TENTHS OF SNOW ACCUMULATION ACROSS
CENTRAL MN AND WESTERN WI.
EXTENDED...NO MAJOR SYSTEMS OUT ON THE HORIZON. WOULDN`T BE
SURPRISED IF WE END UP WITH A LITTLE PRECIP NEXT SUNDAY BASED ON
THE PATTERN INDICATED BY THE ECMWF AND TO A LESSER DEGREE THE
LATEST GFS ENSEMBLE. CPC IS FORECASTING BELOW NORMAL TEMPERATURES
FOR MUCH OF THE COUNTRY IN THE 6-14 DAY OUTLOOKS. ALTHOUGH THE
SIGNAL ISN`T QUITE AS STRONG IN MN/WI...IT FINALLY APPEARS WE
SHOULD GET INTO A MORE WINTER-LIKE AIR MASS AFTER NEXT WEEKEND.
&&
.AVIATION.../06Z TAF ISSUANCE/
WESTERN EDGE OF A PERSISTENT STRATUS DECK CONTINUED TO DRIFT SLOWLY
EASTWARD ARND 8 MPH. HOWEVER...THERE HAS BEEN AN EXPANDING HOLE
IN THE STRATUS DECK TO THE WEST OF MSP AND SOUTH OF STC. ALTHOUGH
BASED ON THE LATEST TRENDS AND MOVEMENT...STC SHOULD SCATTER OUT
BY 6Z...WITH SOME LINGERING CIGS POSSIBLE FOR AN HR OR TWO. FOR
MSP...9Z LOOKS AS THOUGH THE BEST TIMING FOR THE STRATUS TO BEGIN
TO BREAK UP...WITH A TEMPORARY PERIOD FROM 9-11Z OF CIGS OF 2.5K.
RNH/EAU WILL LIKELY NOT SEE ANY IMPROVEMENT UNTIL AFT 12Z...AND
MOST LIKELY AFT 13-15Z BASED ON THE LATEST SATELLITE TRENDS. THE
ONLY PROBLEM IS WHETHER ENOUGH DRIER AIR ACCELERATES THE WESTERN
EDGE OF THIS STRATUS DECK FASTER THAN FORECAST IN THE NEXT FEW
HRS.
WNDS WILL BEGIN FROM THE S/SW AND INCREASE DURING THE MORNING...THEN
BECOME MORE W/NW BY THE AFTN/EVENING AS A COLD FRONT MOVES ACROSS
THE AREA. VFR CIGS ARE EXPECTED WITH THIS FRONTAL PASSAGE...ALONG
WITH DRY WX.
MSP...TIMING OF THE STRATUS DECK REMAINS PROBLEMATIC...WITH THE
BEST BET ARND 9-11Z..,UNLESS DRIER AIR ACCELERATES THIS STRATUS
DECK TO THE EAST FASTER. EITHER CASE...BY 12Z...VFR CONDITIONS
ARE EXPECTED. WNDS WILL BE LIGHT FROM THE WEST...THEN SOUTH BY
MORNING...THEN INCREASING FROM THE SSW BY 18Z...SHIFTING TO THE
SW/W BY 21-22Z. NW WNDS ARE EXPECTED BY EVENING.
VFR CONDITIONS ARE EXPECTED THRU TUES. ..JLT..
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JLT
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
138 AM EST MON NOV 28 2011
.SYNOPSIS...
WEAKENING FRONT AND INCREASING MOISTURE TONIGHT INTO MONDAY...WILL
RESULT IN THICKENING CLOUDS WITH SOME LIGHT SHOWERS OR PATCHY
DRIZZLE. HOWEVER...OUR MAIN BATCH OF RAIN WILL COME FROM A LOW
PRESSURE SYSTEM MOVING THROUGH THE REGION TUESDAY AFTERNOON
THROUGH TUESDAY NIGHT. SOME SHOWERS MAY LINGER INTO WEDNESDAY.
BEHIND THE SYSTEM...TEMPERATURES WILL COOL DOWN TO NEAR NORMAL
LEVELS DURING THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
1030 PM UPDATE... IN THE LAST COUPLE OF HRS...PCPN HAS STARTING
EDGING SLOWLY BACK TWDS THE W. BEING THAT THE SFC FRNT HAS
EFFECTIVELY STALLED ACRS SRN ONT/LK ERIE/OH ATTM...AND THAT DEEP-LYRD
S TO SWLY FLOW WILL BE INCRG IN THE NEXT 12-24 HRS...WE DON`T
EXPECT ANY EWD ADVANCEMENT IN THE NEAR-TERM. WE`VE ADJUSTED
POP/WX GRIDS ACCORDINGLY.
ALSO...TEMPS HAVEN`T FALLEN MUCH AT ALL SO FAR THIS EVE...AND
WE`VE NUDGED OVERNIGHT MINS UP SVRL DEGREES.
8 PM UPDATE... THE LEADING EDGE OF THE -SHRA HAVE MADE IT TO ABT
A KELZ-KPEO-KSYR-KRME LN ATTM. NEAR-TERM NWP GUIDANCE CONTINUES TO
INDICATE THAT ANY FURTHER EWD PUSH TO THE LGT PCPN OVERNIGHT WILL
BE SMALL...AND BASED ON RECENT RADAR TRENDS...WE`RE INCLINED TO GO
ALG WITH THIS THINKING. THUS...SCTD TO NUMEROUS WORDING FOR -SHRA
WILL BE INDICATED IN OUR NRN/WRN ZNS OVERNIGHT...WITH LTL IF ANY
PCPN FARTHER TO THE S AND E...SAVE FOR SOME PATCHY DRZL IN PTNS OF
THE CATSKILLS AND POCONOS TWDS 12Z.
ONLY MINOR TWEAKS WERE MADE TO TEMP/DEW PT GRIDS THROUGH 06Z.
PREV DISC... 4 PM UPDATE...TEMPERATURES TOPPED OUT ROUGHLY 13 TO 17 DEGREES
ABOVE NORMAL...BEING HELD BACK FROM GOING FURTHER ONLY BECAUSE OF
THICKENING HIGH CLOUDS. FRONT IS APPROACHING FROM THE WEST BUT
STRUGGLING...WITH MAINLY ONLY VIRGA SO FAR EXCEPT FOR EXTREME
WESTERN PA AND NY. ONE WEAK WAVE TRAVELING THROUGH THE BRISK
SOUTHWEST FLOW WILL MANAGE TO SKIM STEUBEN COUNTY AND SOME OF THE
WESTERN FINGER LAKES WITH LIGHT SHOWERS DURING THE NEXT FEW
HOURS...THE REST OF THE AREA WILL CONTINUE TO SEE THICKENING HIGH
TO MID LEVEL CLOUDS.
A BIT OF A SQUEEZE PLAY TONIGHT INTO MONDAY MORNING...AS FRONT
STALLS OUT IN OUR NORTHWESTERN ZONES WITH LIGHT SHOWERS COMING OUT
OF TOP-DOWN MOISTENING FROM UPPER LEVELS...YET ALSO SHALLOW MARINE
MOISTURE ATTEMPTS TO RIDE IN ON SOUTHERLY LOW LEVEL FLOW. RUC AND
18Z NAM HAVE BACKED OFF SOMEWHAT ON THIS IDEA HOWEVER...WITH LIGHT
SURFACE WIND VEERING TO INCLUDE SOME WESTERLY COMPONENT...WHICH IS
NOT AS FAVORABLE FOR MARINE MOISTURE TO REACH INTO THE AREA. I
HAVE LIMITED PATCHY DRIZZLE MENTION TO SOME OF THE
POCONOS/CATSKILLS REGION SUSCEPTIBLE TO UPSLOPE FLOW...LATER
TONIGHT INTO EARLY MONDAY MORNING. FARTHER NORTHWEST...NOT AS
MUCH LOW LEVEL MOISTURE...YET ENOUGH MOISTURE IN MID/HIGH LEVELS
FOR LIGHT SHOWERS. CLOUDS HANG AROUND THROUGH MONDAY
AFTERNOON...THOUGH WITH ANY SHOWERS DIMINISHING AS WEAK FRONT
BEGINS TO SLOWLY SHIFT NORTHWARD.
WITH AMOUNT OF CLOUD COVER...ESPECIALLY LATE TONIGHT THROUGH
MONDAY...WILL BE STAYING ON WARM SIDE OF GUIDANCE FOR LOWS
TONIGHT...AND COOLER THAN THE MODELS FOR HIGHS MONDAY.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
GOOD MODEL AGREEMENT ON BIG PICTURE FOR UPPER LOW TO PROGRESSIVELY
MOVE THROUGH THE AREA...WITH MODEL CONSENSUS GIVING US OUR MAIN
BATCH OF RAIN LATE TUESDAY INTO TUESDAY NIGHT. WHILE THERE WILL BE
AN ATLANTIC SUBTROPICAL FEED OF MOISTURE...SPEED OF SYSTEM WILL
MINIMIZE ANY THREAT FOR WATER PROBLEMS. AT THIS TIME WE ARE
EXPECTING AREAL AVERAGE OF LESS THAN AN INCH OF RAINFALL.
HOWEVER...SOME MARGINAL INSTABILITY EVIDENT AS NEGATIVELY TILTED
FRONT COMES THROUGH TUESDAY EVENING...TO THE POINT THAT LATER
SHIFTS MAY NEED TO CONSIDER ADDING MENTION OF THUNDER. WITH
DELAYED TIMING OF FRONT...TEMPERATURES LOOK TO GET QUITE WARM ON
TUESDAY.
COLD CORE OF UPPER LOW PASSES DIRECTLY OVERHEAD WEDNESDAY...AND
EXPECTING SCATTERED SHOWERS IN THE WRAP AROUND MOISTURE OF THE
COMMA HEAD. DESPITE STRONG COLD AIR ADVECTION...925-850MB
TEMPERATURES DO NOT SUPPORT SHOWERS CHANGING OVER TO SNOW DURING
THE DAY WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
PERIOD BEGINS WITH VIGOROUS STORM SYSTEM EXITING TO THE EAST, AND
HIGH PRESSURE BUILDING NORTHWARD FROM THE LOWER OHIO VALLEY.
A WEAK LOW PRESSURE CENTER AND ASSOCIATED FRONT WILL MOVE OVER
LAKE ONTARIO EARLY FRIDAY, BRINGING WITH IT A CHANCE FOR A RAIN OR
SNOW SHOWER.
A TROF WILL DIG INTO ONTARIO PROVINCE SATURDAY INTO SUNDAY, WITH
SOME JET ACTIVITY ALONG THE US/CANADIAN BORDER. THIS WILL BRING
A BETTER CHANCE FOR SNOW SHOWERS, ESPECIALLY OVER NY STATE, THIS
WEEKEND.
TEMPERATURES WILL FLUCTUATE BETWEEN SYSTEMS, BUT OVERALL WILL BE
TRENDING BACK TOWARD SEASONABLY COOL READINGS.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
130 AM UPDATE...A COLD FRONT ACROSS WESTERN NEW YORK WILL STALL ACROSS OR
NEAR THE NORTHERN TERMINALS BY DAYBREAK. BEHIND THIS FRONT IFR
CIGS HAVE DEVELOPED OVER WESTERN NY AT KBUF AND KIAG. THE HRRR
ALONG WITH THE LATEST GFS AND NAM SOUNDINGS SHOW IFR CIGS
DEVELOPING AT KRME AND KSYR BY 12Z. SOME UNCERTAINTY EXISTS WITH
HOW FAR SOUTH THE FRONT WILL PUSH AND ULTIMATELY THE IFR RESTRICTIONS.
DECIDED TO CONTINUE TO PREVAIL MVFR CIGS DURING THIS TIME WITH
JUST A TEMPO GROUP OF IFR. IF WE GO DOWN TO IFR...IFR CIGS WILL
LIKELY PERSIST THROUGH AT LEAST MIDDAY.
TOUGHER CALL AT THE SOUTHERN TERMINALS. THE FRONT MENTIONED ABOVE
WILL NOT MOVE THROUGH THESE TERMINALS SO IFR TO MVFR CIGS THAT THE
MODELS CONTINUE TO INDICATE ARE MUCH MORE UNCERTAIN. DESPITE
REMAINING SOUTH OF THE COLD FRONT...THE MODELS SHOWS MVFR TO IFR
(AT THE ELEVATED SITES) CIGS DEVELOPING NEAR 12Z...AND FORM THIS
DECK OVERHEAD OR IN PLACE. WITH NO UPSTREAM OBS TO SUPPORT THIS...
JUST TOO LITTLE CONFIDENCE TO INCLUDE MORE THAN AN MVFR TEMPO
GROUP FOR CIGS JUST AT THE ELEVATED SITES (KITH/KBGM) AROUND 12Z.
WILL CONTINUE TO MONITOR AND UPDATE AS NEEDED WITH THE 09Z UPDATE.
BEYOND THIS MORNING CIGS IMPROVE LATER TODAY AND TONIGHT AS HIGH
PRESSURE BUILDS IN AND VFR RETURNS.
OUTLOOK...
MON NGT...IFR/MVFR. PERIODS OF RAIN AND FOG.
TUE THRU THU...PATCHY MVFR IN SCT -SHRA. SCT -SHSN AND MVFR/BRIEF
IFR POSSIBLE BEGINNING WED.
FRI...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MLJ/MDP
SHORT TERM...MDP
LONG TERM...DJP
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
454 AM EST MON NOV 28 2011
.SYNOPSIS...
LOW PRESSURE WILL TRACK NORTH NORTHEAST ALONG A STALLED FRONT
WHICH WILL CONTINUE THE WET WEATHER ACROSS THE AREA. THE LOW WILL
MOVE ACROSS THE REGION ON TUESDAY. COLD AIR WRAPPING IN BEHIND THE
LOW WILL CHANGE LINGERING RAIN SHOWERS OVER TO SNOW SHOWERS BEFORE
THE PRECIPITATION ENDS ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ALTHOUGH THERE HAVE BEEN SOME BREAKS IN THE PRECIPITATION...RAIN
CONTINUES PRETTY MUCH AREA WIDE WITH PLENTY MORE UPSTREAM. AS THE
DAY PROGRESSES...LOW PRESSURE WILL APPROACH AND PULL THE OLD FRONT
BACK WEST INTO THE FORECAST AREA. THIS WILL ALSO ALLOW THE MAIN
PRECIPITATION AXIS TO SHIFT WEST SLIGHTLY. THERE SHOULD BE SOME
DRYING IN THE EASTERN COUNTIES WHERE THE FRONT PASSES AGAIN. BUT
NOT CONVINCED THAT IT WILL BE AS SHARP A CUT OFF IN PRECIPITATION
AS THE NAM AND RUC ARE SUGGESTING. HOWEVER IT SHOULD BE ENOUGH
FOR TEMPERATURES TO WARM MORE IN THOSE LOCATIONS THAN POINTS TO
THE WEST.
APPEARS THAT RAINFALL AMOUNTS WILL BE SLIGHTLY HIGHER IN THE TRI-
STATE AREA. BUT EVEN THERE IT SHOULD BE LESS THAN AN INCH IN A
MOSTLY LIGHT STEADY RAIN. THIS COULD LEAD TO SOME PONDING PROBLEMS
BUT POTENTIAL FOR SIGNIFICANT FLOODING DOES NOT LOOK PARTICULARLY
HIGH AT THIS POINT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
LOW PRESSURE WILL OCCLUDE AS IT APPROACHES THE REGION TONIGHT AND
LIFTS ACROSS THE AREA TOMORROW. RAIN WILL CONTINUE UNTIL DRY AIR
THAT HAS WRAPPED INTO THE SYSTEM PUSHES NORTH TUESDAY AFTERNOON
AND EVENING. THERE COULD BE A HEAVIER BURST OF RAIN ALONG AND
AHEAD OF THE OCCLUDED FRONT/LOW BUT FOR THE MOST PART THIS SHOULD
BE A CONTINUATION OF LIGHT STEADY RAIN. THERE COULD EVENTUALLY END
UP BEING SOME MINOR AREAL FLOOD ISSUES. ALSO RIVERS WILL RISE IN
RESPONSE TO THE RAINFALL WITH THE POTENTIAL FOR A FEW POINTS TO GO
INTO FLOOD. THIS HEIGHTEN FLOOD POTENTIAL STILL APPEARS TO BE A
DAY OUT. SO WILL CONTINUE TO HIGHLIGHT THIS IN THE HWO.
PRECIPITATION AND COLDER AIR WILL WRAP BACK ACROSS THE AREA
TUESDAY NIGHT. THIS WILL RESULT IN RAIN SHOWERS CHANGING TO SNOW
SHOWERS. THERE COULD BE SOME LIGHT ACCUMULATIONS PARTICULARLY ON
GRASSY SURFACES. AN INCH OR SO IS POSSIBLE IN THE FAR NORTHWEST
COUNTIES WHICH WILL BE NEAR A DEFORMATION ZONE AND THUS GREATER
PRECIPITATION AMOUNTS. SNOW SHOWERS WILL CONTINUE INTO WEDNESDAY
AS A SECONDARY TROUGH ROTATES AROUND THE DEPARTING LOW. CONDITIONS
WILL IMPROVE BY WEDNESDAY AFTERNOON WITH CLEARING WORKING IN FROM
THE WEST.
TEMPERATURES WILL BE CHALLENGING PARTICULARLY TONIGHT AND TUESDAY
WITH THE APPROACH AND PASSAGE OF THE LOW/OCCLUDED FRONT. EXPECT A
MILD NIGHT WITH TEMPERATURES RISING IN SOME LOCATIONS. THEN COLDER
AIR WILL OVERSPREAD THE REGION ON TUESDAY RESULTING IN MORNING
HIGHS AND FALLING TEMPERATURES. HAVE GONE SLIGHTLY ABOVE GUIDANCE
FOR LOWS TUESDAY NIGHT AND USED A MOS BLEND ON WEDNESDAY WITH COLD
ADVECTION AND MOSTLY CLOUDY SKIES NOT ALLOWING FOR MUCH OF A WARM
UP.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL BUILD IN FOR THE BEGINNING OF THE PERIOD. A
WEAK FRONT WILL SLIDE BY TO THE NORTH ON FRIDAY. MODELS HAVE COME
INTO AGREEMENT THAT THERE IS LIMITED PRECIPITATION POTENTIAL AT
BEST WITH THIS BOUNDARY. ANOTHER HIGH WILL QUICKLY TRAVERSE THE
AREA ON SATURDAY. THEN ANOTHER FRONT WILL MOVE IN FOR SUNDAY. BUT
IT APPEARS THAT THIS LATTER BOUNDARY WILL BE ABLE TO TAP MORE
MOISTURE. SO HAVE INCLUDED CHANCE POPS THEN.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
CONDITIONS CURRENTLY RANGE FROM VFR TO IFR ACROSS THE AREA TAF
SITES ALTHOUGH MOST LOCATIONS ARE IN THE MVFR TO IFR CATEGORY.
WIDESPREAD RAIN WILL CONTINUE THROUGH THE OVERNIGHT HOURS AND INTO
THE DAY ON MONDAY. A FEW WIND GUSTS WILL ALSO BE POSSIBLE DURING
THE DAYTIME HOURS ON MONDAY ACROSS THE AREA. WIND GUSTS WILL
GENERALLY BE IN THE 18 TO 20 KNOT RANGE. SOME DRIER AIR WILL TRY
TO WORK IN BRIEFLY FROM THE EAST MONDAY EVENING AND REFLECTED THIS
IN THE TAFS. AS THE LOW NEARS THE AREA MONDAY NIGHT HOWEVER CIGS
WILL LOWER AND RAIN WILL ONCE AGAIN RETURN TO THE TAF SITES.
OUTLOOK...MVFR/IFR CIGS/VSBYS MONDAY NIGHT INTO WEDNESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...NOVAK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
310 AM CST MON NOV 28 2011
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT
310 AM CST MON NOV 28 2011
THE MAIN STORIES IN THE SHORT TERM ARE WITH THE PESKY STRATUS
THAT IS CURRENTLY DRAPED OVER MUCH OF THE REGION ALONG WITH THE
CHANCES FOR A LIGHT ACCUMULATION OF SNOW ON THURSDAY.
CURRENTLY...A SURFACE RIDGE OF HIGH PRESSURE EXTENDS FROM THE
SOUTHERN PLAINS THROUGH SOUTHEAST MINNESOTA AND LAKE SUPERIOR. A
STUBBORN LOW LEVEL STRATUS DECK REMAINS IN PLACE ACROSS MUCH OF
THE REGION ALONG THE EASTERN PERIPHERY OF THIS RIDGE. THE WESTERN
EDGE OF THIS CLOUD SHIELD HAS STARTED TO DRIFT EASTWARD OVERNIGHT
ACROSS EASTERN MINNESOTA AND SHOULD COME THROUGH THE FORECAST
AREA FROM WEST TO EAST TODAY. THE AREA OF LEAST CONFIDENCE IN THE
CLEARING OCCURRING IS IN FAR NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN AS THE STRATUS HAS BEEN SLOW TO MOVE IN CENTRAL IOWA.
THE 28.00Z NAM AND GFS APPEAR TO HAVE INITIALIZED TOO LOW ON THE
RH UNDER THE 900MB INVERSION...BUT THE 28.05Z RUC SEEMS TO HAVE A
BETTER HANDLE ON THE LOW LEVEL MOISTURE. THUS...HAVE GONE WITH A
PESSIMISTIC BLEND OF THE RUC AND PURE IR SATELLITE EXTRAPOLATION
TO GET THE CLEARING TREND DOWN. THIS CLOUD COVER WILL HAVE AN
IMPACT ON TEMPERATURES TODAY WITH THE HIGHEST VALUES TO THE
NORTHWEST WHERE THE SUN WILL BE OUT LONGER.
AFTER A BRIEF CLEAR PERIOD GOING INTO THE EVENING...MID TO HIGH
LEVEL CLOUD COVER WILL BE ON THE INCREASE AS A MID LEVEL TROUGH
NEAR SASKATCHEWAN DROPS SOUTHEAST INTO THE REGION. AS THIS TROUGH
INTERACTS WITH A CUTOFF LOW IN THE SOUTHEASTERN US IT WILL LOSE
SOME OF ITS BETTER FORCING WITH PV ADVECTION SHOWING A RAPID
DECREASE. WHILE PRECIPITATION LOOKS UNLIKELY...THIS TROUGH WILL
BRING A COLD FRONT ALONG WITH IT THAT WILL TRACK THROUGH TONIGHT.
WITH A SURFACE LOW TRACKING TO THE NORTH THROUGH THE OHIO RIVER
VALLEY AND A RIDGE OF HIGH PRESSURE FOLLOWING THE COLD FRONT...THE
UPPER MISSISSIPPI RIVER VALLEY WILL BE STUCK IN BETWEEN THESE TWO
FEATURES WITH A TIGHTENING PRESSURE GRADIENT. AS A RESULT...WIND
GUSTS OF 20-30KT WILL BE POSSIBLE ON TUESDAY...PARTICULARLY ACROSS
NORTHEAST IOWA AND SOUTHWEST WISCONSIN WHERE THE GRADIENT WILL BE
THE TIGHTEST.
THIS RIDGE OF HIGH PRESSURE WILL GRADUALLY SLIDE EASTWARD INTO THE
REGION WEDNESDAY INTO EARLY THURSDAY AND PROVIDE FOR SOME FAIRLY
COOL TEMPERATURES WITH LOWS IN THE TEENS. THE NEXT FEATURE OF NOTE IS
WITH A MID LEVEL TROUGH THAT IS EXPECTED TO DROP INTO THE REGION
ON THURSDAY. OVER THE PAST FEW DAYS...THE MODELS HAVE BEEN PRETTY
LOW ON PRODUCING ANY QPF OUT OF THIS FEATURE. HOWEVER...THE LATEST
TREND IS TO BE MUCH STRONGER WITH THIS MID LEVEL FEATURE AND
THEY SHOW QUITE A BIT OF QG FORCING WITH TROUGH. TEMPERATURES
WOULD BE COLD ENOUGH TO SUPPORT ALL SNOW ALONG AND BEHIND THE COLD
FRONT WHERE THE PRECIPITATION IS EXPECTED TO FORM. THIS LOOKS TO
BE A FAIRLY QUICK HITTER WITH LESS THAN A 6 HOUR WINDOW OF SEEING
THE SNOWFALL...SO TOTALS SHOULD BE FAIRLY LIGHT IF THIS DOES TAKE
SHAPE WITH THE SNOW ENDING THURSDAY NIGHT AS THE FORCING DROPS TO
THE SOUTHEAST OF THE REGION.
.LONG TERM...FRIDAY THROUGH SUNDAY NIGHT
310 AM CST MON NOV 28 2011
AFTER A RIDGE OF HIGH PRESSURE MOVES THROUGH ON FRIDAY...THE FOCUS
WILL BE ON THE WEEKEND AND WHETHER PRECIPITATION WILL FILL IN FROM
THE SOUTHWEST AS THE 27.00Z AND 26.12Z ECMWF IS SUGGESTING. THE
27.00Z SHOWS THE MID LEVEL CUT OFF LOW OVER THE FOUR CORNERS
REGION GETTING PICKED UP INTO THE NEXT TROUGH THAT TRACKS THROUGH
THE NORTHERN PLAINS SATURDAY INTO SUNDAY. THE 27.00Z
GFS...HOWEVER...KEEPS THIS LOW OUT OVER THE DESERT AND BRINGS THE
NORTHERN STREAM TROUGH THROUGH A LITTLE LESS AMPLIFIED. WITH A
COLD FRONT STALLED OUT JUST TO THE SOUTHEAST...PRECIPITATION IS
EXPECTED TO DEVELOP IN THE VICINITY OF IT AS THIS WAVE GETS PICKED
UP. TEMPERATURES SHOULD BE COLD ENOUGH TO SUPPORT ALL SNOW...SO
THIS SYSTEM WILL HAVE TO BE MONITORED FOR TRENDS AS THE GFS WOULD
SUGGEST THAT CONDITIONS WOULD BE DRY UNTIL SUNDAY NIGHT WHEN A
SYSTEM DROPS OUT OF SOUTHWESTERN CANADA.
&&
.AVIATION...THROUGH 06Z TUESDAY
1136 PM CST SUN NOV 27 2011
CONCERN CONTINUES TO BE ON WHEN STRATUS DECK WILL CLEAR THE TAF
SITES. SATELLITE TRENDS THROUGHOUT THE EVENING INDICATE THE BACK
EDGE OF THE STRATUS DECK HAS BEEN SLOWLY PUSHING EASTWARD. ONCE
AGAIN MODELS NOT DEPICTING THE LOW LEVEL MOISTURE WELL AT ALL AND
THUS HAVE BASED CLEARING TREND BASED ON THE BACK EDGE
SPEED AND POSITION OF THE SURFACE RIDGE AND 925MB WINDS...WHICH IS
SIMILAR TO THE TIMING IN THE 00Z TAFS SO NO MAJOR CHANGES. ONCE
STRATUS CLEARS...VFR CONDITIONS WILL PREVAIL WITH ONLY A FEW
CLOUDS EXPECTED AFTER 00Z TUESDAY.
A COLD FRONT PUSHES THROUGH THE AREA AFTER MONDAY EVENING...WITH
THE WINDS BECOMING NORTHWESTERLY. THE PRESSURE GRADIENT DOES
TIGHTEN...AND EXPECT WINDS AT 12 KNOTS OR GREATER AFTER 04Z AT
KRST...WITH THE INCREASE AT KLSE AFTER 06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
310 AM CST MON NOV 28 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1136 PM CST SUN NOV 27 2011
.SHORT TERM...TONIGHT THROUGH WEDNESDAY
255 PM CST SUN NOV 27 2011
MAIN FORECAST CONCERN IS ON CLOUDS/TEMPERATURES TONIGHT INTO MONDAY.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED TROUGHING OVER BRITISH COLUMBIA...RIDGING FROM SOUTHERN
CALIFORNIA NORTHEASTWARD INTO SOUTHERN MANITOBA...AND TROUGHING FROM
JAMES BAY SOUTHWEST THROUGH WISCONSIN AND DOWN INTO EASTERN TEXAS.
WITH THE FORECAST AREA ON THE WEST SIDE OF THIS LATTER UPPER
TROUGHING...MID TO UPPER LEVEL SUBSIDENCE IS OCCURRING. THIS CAN BE
SEEN ON 12Z SOUNDINGS FROM ABR...MPX AND DVN. ALSO OF NOTE ON THE
MPX AND DVN SOUNDINGS IS A NEAR TO FULLY SATURATED LAYER FROM 910MB
TO AT LEAST 850MB...REPRESENTATIVE OF THE STRATUS DECK IN PLACE AT
THE TIME. LATEST VISIBLE SATELLITE IMAGERY SHOWED THE STRATUS
COVERING THE ENTIRE FORECAST AREA AND EXTENDING WEST TO A
NORTH-SOUTH LINE THROUGH WINDOM MINNESOTA. GOING A LITTLE FARTHER
WEST...A SURFACE RIDGE IS PRESENT ALONG THE DAKOTAS/MINNESOTA
BORDER. NORTHWEST WINDS REMAIN GUSTY AHEAD OF THE RIDGE WITH GUSTS
OF 20-25 KT OVER THE FORECAST AREA. TEMPERATURES HAVE ALSO STRUGGLED
TO RISE MUCH TODAY...DUE TO A COMBINATION OF THE STRATUS LIMITING
DIURNAL HEATING AND 850MB TEMPS OF -9C OBSERVED AT MPX ON ITS 12Z
SOUNDING.
MUCH OF THE SHORT TERM PERIOD LOOKS QUIET FOR THE FORECAST AREA...
THOUGH THERE ARE A FEW FEATURES TO WATCH. FIRST IS THE SOUTHERN END
OF THE CURRENT UPPER TROUGH IN EAST TEXAS. ALL MODELS AGREE ON THE
SOUTHERN END CLOSING OFF INTO AN UPPER LOW OVER THE SOUTHEASTERN
U.S. MONDAY INTO MONDAY NIGHT...WHICH RESULTS IN SURFACE LOW
DEVELOPMENT ON ITS NORTH SIDE OVER KENTUCKY AND TENNESSEE. THE UPPER
AND SURFACE LOWS THEN GET LIFTED NORTHEAST THROUGH THE EASTERN U.S.
FOR TUESDAY INTO WEDNESDAY...IN RESPONSE TO THE CURRENT BRITISH
COLUMBIA TROUGH MOVING THROUGH THE FORECAST AREA ON TUESDAY. AS OF
NOW IT APPEARS ANY DEFORMATION PRECIPITATION ON THE NORTHWEST SIDE
OF THE UPPER AND SURFACE LOWS WILL STAY TO THE SOUTHEAST...THANKS TO
THAT BRITISH COLUMBIA UPPER TROUGH...PERHAPS REACHING AT MOST THE
ROCKFORD ILLINOIS AREA. OTHERWISE...MUCH OF THE REST OF THE TIME THE
FORECAST AREA SHOULD BE DOMINATED BY SUBSIDENCE AND DRY AIR...DUE TO
UPPER RIDGING COMING ACROSS ON MONDAY AND AGAIN TUESDAY NIGHT INTO
WEDNESDAY...RESULTING IN DRY CONDITIONS.
CLOUD COVER FORECAST IS PROBLEMATIC...ESPECIALLY TONIGHT WITH THE
STRATUS STUCK IN PLACE BELOW THE SUBSIDENCE INVERSION. TYPICALLY TO
GET RID OF STRATUS IN THESE CASES...ESPECIALLY THIS TIME OF YEAR
WITH THE VERY LOW SUN ANGLE...THE SURFACE RIDGE NEEDS TO MOVE IN
AND/OR THROUGH. 27.12Z NAM/GFS SEEM TOO AGGRESSIVE BY CLEARING
THINGS OUT BY 21Z IN OUR WESTERN FORECAST AREA TODAY...WHICH IS
ALREADY TOO FAST PER LATEST SATELLITE IMAGERY. FOLLOWED MORE OF AN
IDEA PRESENTED BY THE RUC AND 925MB WIND FORECASTS...WHICH WOULD
SUGGEST CLEARING MAINLY OCCURRING AFTER MIDNIGHT TONIGHT INTO
MID-DAY MONDAY...WORKING FROM NORTHWEST TO SOUTHEAST AS 925MB WINDS
TURN SOUTHWESTERLY. IT IS POSSIBLE GRANT COUNTY STAYS CLOUDY ALL DAY
MONDAY WITH 925MB WINDS STILL FORECAST NEAR CALM OR OUT OF THE
NORTHEAST...SOMETHING THAT WILL HAVE TO BE MONITORED. OTHERWISE...
SHOULD GET A BAND OF MID/HIGH CLOUDS TO COME ACROSS MONDAY NIGHT
INTO TUESDAY WITH THE BRITISH COLUMBIA UPPER TROUGH. MORE HIGH
CLOUDS LOOK TO MOVE THROUGH WEDNESDAY AFTERNOON AS THE UPPER RIDGE
AXIS CROSSES THE FORECAST AREA.
TEMPERATURES ARE ALSO TRICKY. RAISED LOW TEMPERATURES UP FOR MOST
AREAS TONIGHT INTO THE MID TO UPPER 20S...EXCEPT FOR THE FAR WEST
WHERE CLEARING AND LIGHTER WINDS SHOULD ALLOW TEMPS TO TANK INTO THE
UPPER TEENS TO AROUND 20. STILL SHOULD SEE A DECENT AMOUNT OF SUN ON
MONDAY TO ALLOW TEMPS TO CLIMB INTO THE MID 30S TO LOW 40S...AIDED
BY 850MB TEMPS REACHING 4-6C BY LATE AFTERNOON AHEAD OF THE UPPER
TROUGH. LOOK FOR A COOL DOWN ON TUESDAY AS THE UPPER TROUGH
CROSSES...DROPPING 850MB TEMPS DOWN TO -2 TO -4C AND THUS HIGHS INTO
THE LOW TO MID 30S. TUESDAY NIGHT COULD BE QUITE CHILLY WITH A
SURFACE RIDGE CROSSING AND CLEAR SKIES. STAYED WITH A BLEND OF
GUIDANCE THEN. MODERATION IN TEMPERATURES IS EXPECTED AGAIN ON
WEDNESDAY WITH THE UPPER RIDGE COMING IN...BRINGING 850MB TEMPS UP
TO 1-3C.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
255 PM CST SUN NOV 27 2011
SIMILAR TO YESTERDAY...MODELS AND GFS ENSEMBLES ARE IN PRETTY GOOD
AGREEMENT THROUGH FRIDAY ON THE UPPER AIR PATTERN...THEN BEGIN TO
DIVERGE ON HOW TO HANDLE THE WEEKEND. FIRST FEATURE OF INTEREST IS A
LONG WAVE TROUGH EXTENDING FROM SASKATCHEWAN INTO CALIFORNIA AT 00Z
THURSDAY. MODELS PROG THIS TROUGH TO SPLIT INTO TWO...WITH THE
NORTHERN PORTION CROSSING THE FORECAST AREA THURSDAY NIGHT. AHEAD OF
THE TROUGH...MODELS HAVE BECOME IN BETTER AGREEMENT ALL SHOWING SOME
LIGHT SNOW COMING THROUGH...THOUGH FOR THE 27.12Z ECMWF IT IS A
CHANGE FROM ITS PREVIOUS RUN WHICH HAD NO SNOW DUE TO DRY LOW
LEVELS. THEREFORE...ONLY HAVE 20 PERCENT CHANCES OF SNOW AT THE
MOMENT. LATER FORECASTS MAY NEED HIGHER CHANCES IF MODELS STAY IN
AGREEMENT. DRY AND COLDER CONDITIONS LOOK ON TAP FOR THURSDAY NIGHT
INTO FRIDAY AS 850MB TEMPS DROP TO -8 TO -10C AND SURFACE HIGH
PRESSURE BUILDS IN. THE WEEKEND FEATURES ISSUES REGARDING HANDLING
SHORTWAVES DROPPING DOWN OFF A BUILDING EASTERN PACIFIC RIDGE...AND
IF THESE SHORTWAVES CAN POSSIBLY PHASE WITH THE SOUTHERN END OF THE
LONG WAVE TROUGH THAT GOT CUT-OFF ON THURSDAY. THE 27.12Z GFS AND
SOME OF ITS ENSEMBLES SAY THE CUT-OFF LOW REMAINS...RESULTING IN A
DRY NORTHWEST FLOW PATTERN FOR THE WEEKEND. THE 27.12Z ECMWF AND
EXTRAPOLATION OF THE 27.12Z UKMET/CANADIAN SUGGEST A PHASING OR AT
LEAST THE UPPER LOW GETTING KICKED NORTHEAST TOWARDS THE FORECAST
AREA. HARD TO SAY WHICH ONE IS RIGHT AT THIS MOMENT...BUT SINCE
VERIFICATION WISE THE ECMWF TENDS TO A LITTLE BETTER AND DOES HAVE
SOME CONSISTENCY FROM ITS PREVIOUS RUN...TEND TO LEAN MORE TOWARDS
THE ECMWF/UKMET/CANADIAN CAMP. UNDER THIS SCENARIO...SATURDAY SHOULD
STILL END UP DRY WITH MODERATION AS RETURN FLOW SETS UP BEHIND
FRIDAYS SURFACE RIDGE. ISENTROPIC LIFT/WARM ADVECTION THEN SET UP
FOR SATURDAY NIGHT ACROSS FAR SOUTHERN AREAS OF THE CWA...AND ACROSS
THE REST OF THE FORECAST AREA ON SUNDAY AS THE UPPER LOW APPROACHES.
PLACED IN 20 PERCENT CHANCES AT THE PRESENT TIME...GIVEN THE
UNCERTAINTY PRESENT WITH THE GFS SCENARIO AND SOME OF THE GFS
ENSEMBLES.
&&
.AVIATION...THROUGH 06Z TUESDAY
1136 PM CST SUN NOV 27 2011
CONCERN CONTINUES TO BE ON WHEN STRATUS DECK WILL CLEAR THE TAF
SITES. SATELLITE TRENDS THROUGHOUT THE EVENING INDICATE THE BACK
EDGE OF THE STRATUS DECK HAS BEEN SLOWLY PUSHING EASTWARD. ONCE
AGAIN MODELS NOT DEPICTING THE LOW LEVEL MOISTURE WELL AT ALL AND
THUS HAVE BASED CLEARING TREND BASED ON THE BACK EDGE
SPEED AND POSITION OF THE SURFACE RIDGE AND 925MB WINDS...WHICH IS
SIMILAR TO THE TIMING IN THE 00Z TAFS SO NO MAJOR CHANGES. ONCE
STRATUS CLEARS...VFR CONDITIONS WILL PREVAIL WITH ONLY A FEW
CLOUDS EXPECTED AFTER 00Z TUESDAY.
A COLD FRONT PUSHES THROUGH THE AREA AFTER MONDAY EVENING...WITH
THE WINDS BECOMING NORTHWESTERLY. THE PRESSURE GRADIENT DOES
TIGHTEN...AND EXPECT WINDS AT 12 KNOTS OR GREATER AFTER 04Z AT
KRST...WITH THE INCREASE AT KLSE AFTER 06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
255 PM CST SUN NOV 27 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
845 AM EST MON NOV 28 2011
.SYNOPSIS...
SLOW MOVING LOW PRESSURE WILL BRING PERIODS OF RAIN FOR THE FIRST
HALF OF THE WEEK. MILD TEMPERATURES EARLY IN THE WEEK WILL COOL
SIGNIFICANTLY BY WEDNESDAY...WITH RESIDUAL RAIN SHOWERS CHANGING
TO SNOW.
&&
.NEAR TERM /THROUGH TONIGHT/...
ONLY CHANGE THIS UPDATE WILL BE TO INCREASE THE CHANCE OF PRECIP
IN THE EXTERME WESTERN PART OF THE CWA NEAR ZZV TO REFLECT THE
CURRENT RADAR TRENDS. REST UNCHANGED.
A LARGE UPPER LEVEL TROUGH WILL CONTINUE TO DIG SOUTH ACROSS THE
MISSISSIPPI VALLEY TODAY. WITH THE NORTHERN BRANCH UPPER LOW
EJECTING NORTHEAST INTO THE CANADIAN MARITIMES...THIS WILL RESULT
IN SPLIT FLOW DEVELOPING ACROSS THE UPPER OHIO VALLEY LATER TODAY.
HENCE...PRECIP COVERAGE WILL BEGIN TO DIMINISH THIS MORNING...WITH
ISOLATED TO SCATTERED SHOWERS REMAINING FOR THIS AFTN INTO THE
EVENING. BY LATER TONIGHT...THE UPPER TROUGH ACROSS THE MS VALLEY
WILL PULL NORTHWARD...BRINGING AN INCREASING COVERAGE OF SHOWERS
BACK INTO THE FCST. AHEAD OF THE UPPER TROUGH...WARM AIR WILL
CONTINUE TO SURGE NORTHWARD...AND WITH PERHAPS SOME CLOUD BREAKS
IN THE AFTN...EXPECT HIGH TEMPERATURES IN THE UPPER 50S TO LOWER
60S...WITH SOME MID 60S POSSIBLE NEAR/SOUTH OF THE MASON DIXON.
WITH WARM AIR REMAINING ACROSS THE AREA TNGT...ALONG WITH
CLOUDS...EXPECT VERY MILD LOW TEMPERATURES IN THE LOWER TO MID
50S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
THE UPPER LOW PRESSURE SYSTEM IS PROGGED TO MIGRATE NORTH INTO
THE REGION TUESDAY INTO TUESDAY NIGHT...EJECTING NORTHEAST
WEDNESDAY. WIDESPREAD SHOWERS WILL PREVAIL FOR MOST OF TUESDAY
WITH A GRADUAL DECREASING TREND TUESDAY NIGHT...AND MAINLY
SCATTERED PRECIP WEDNESDAY. EXPECTED POSITIONING OF OCCLUDING
SURFACE FRONT...FORECAST TRACK OF THE LOW...AND MID LEVEL DRY
PUNCH MAY LIMIT PRECIP TOTALS...BUT WITH AMOUNTS FORECAST IN
THE 1 INCH RANGE...ON TOP OF SUNDAY/MONDAY RAINFALL...WILL
CONTINUE MENTION OF STREAM RISES IN THE HAZARDOUS WEATHER OUTLOOK.
AS THE UPPER LOW MOVES NORTHEAST OF THE AREA...MUCH COLDER AIR
WILL ENTER THE REGION...WITH PRECIP CHANGING OVER TO SNOW FOR MOST
AREAS WEDNESDAY. WITH TEMPERATURES REMAINING ABOVE FREEZING UNTIL
WEDNESDAY NIGHT...AND EXPECTED LIGHT SNOWFALL RATES...DO NOT
EXPECT SIGNIFICANT ACCUMULATION...WITH PERHAPS AN INCH OR SO ON
THE RIDGES AND ALONG THE I-80 CORRIDOR.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BUILD ACROSS THE AREA THURSDAY FOR DRY BUT
CHILLY CONDITIONS. MODELS HAVE BEEN CONSISTENT WITH A WEAK COLD
FRONT CLIPPING THE AREA LATE FRIDAY/FRIDAY NIGHT. WITH LIMITED
MOISTURE...WILL USE LOW END CHANCE POPS. DRY AND CHILLY CONDITIONS
ARE EXPECTED FOR THE WEEKEND.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
PER RECENT SURFACE AND RADAR DATA ALONG WITH HRRR AND NAM MODEL
OUTPUT, EXPECT FRONTAL RAIN BAND, NORTHEAST OF KENTUCKY LOW PRESSURE
CENTER TO REMAIN OVER MUCH OF THE UPPER OHIO VALLEY THROUGH 15Z,
BEFORE PIVOTING NORTHWESTWARD THE REST OF TODAY.
WITH THE RAIN BAND, THERE CAN BE PERIODS OF IFR THROUGH 15Z,
ALTHOUGH MVFR CONDITIONS WILL BE MORE PREVALENT. AS THE RAIN BAND
EXITS NORTHWEST, EXPECT VFR TO BECOME THE PREVALENT FLIGHT CONDITION
THIS AFTERNOON, EXCEPT FOR MAYBE KZZV AND KFKL.
OUTLOOK...MONDAY NIGHT THROUGH FRIDAY....
NORTHEASTWARD MOVING COLD FRONTAL BAND OF RAIN WILL PROVIDE RENEWED
RESTRICTIONS LATE TUESDAY MORNING INTO TUESDAY NIGHT. POST SYSTEM
WRAP AROUND SHOWERS OF RAIN AND SNOW MAY CAUSE ADDITIONAL SHORT
PERIODS OF RESTRICTIONS WEDNESDAY. AFTER VFR UNDER HIGH PRESSURE
THURSDAY, COLD FRONTAL SHOWERS OF RAIN OR SNOW MAY PROVIDE
RESTRICTIONS FRIDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
636 AM EST MON NOV 28 2011
.SYNOPSIS...
SLOW MOVING LOW PRESSURE WILL BRING PERIODS OF RAIN FOR THE FIRST
HALF OF THE WEEK. MILD TEMPERATURES EARLY IN THE WEEK WILL COOL
SIGNIFICANTLY BY WEDNESDAY...WITH RESIDUAL RAIN SHOWERS CHANGING
TO SNOW.
&&
.NEAR TERM /THROUGH TONIGHT/...
A LARGE UPPER LEVEL TROUGH WILL CONTINUE TO DIG SOUTH ACROSS
THE MISSISSIPPI VALLEY TODAY. WITH THE NORTHERN BRANCH UPPER LOW
EJECTING NORTHEAST INTO THE CANADIAN MARITIMES...THIS WILL RESULT
IN SPLIT FLOW DEVELOPING ACROSS THE UPPER OHIO VALLEY LATER TODAY.
HENCE...PRECIP COVERAGE WILL BEGIN TO DIMINISH THIS MORNING...WITH
ISOLATED TO SCATTERED SHOWERS REMAINING FOR THIS AFTN INTO THE
EVENING. BY LATER TONIGHT...THE UPPER TROUGH ACROSS THE MS
VALLEY WILL PULL NORTHWARD...BRINGING AN INCREASING COVERAGE OF
SHOWERS BACK INTO THE FCST. AHEAD OF THE UPPER TROUGH...WARM
AIR WILL CONTINUE TO SURGE NORTHWARD...AND WITH PERHAPS SOME CLOUD
BREAKS IN THE AFTN...EXPECT HIGH TEMPERATURES IN THE UPPER 50S
TO LOWER 60S...WITH SOME MID 60S POSSIBLE NEAR/SOUTH OF THE
MASON DIXON. WITH WARM AIR REMAINING ACROSS THE AREA TNGT...ALONG
WITH CLOUDS...EXPECT VERY MILD LOW TEMPERATURES IN THE LOWER TO
MID 50S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
THE UPPER LOW PRESSURE SYSTEM IS PROGGED TO MIGRATE NORTH INTO
THE REGION TUESDAY INTO TUESDAY NIGHT...EJECTING NORTHEAST
WEDNESDAY. WIDESPREAD SHOWERS WILL PREVAIL FOR MOST OF TUESDAY
WITH A GRADUAL DECREASING TREND TUESDAY NIGHT...AND MAINLY
SCATTERED PRECIP WEDNESDAY. EXPECTED POSITIONING OF OCCLUDING
SURFACE FRONT...FORECAST TRACK OF THE LOW...AND MID LEVEL DRY
PUNCH MAY LIMIT PRECIP TOTALS...BUT WITH AMOUNTS FORECAST IN
THE 1 INCH RANGE...ON TOP OF SUNDAY/MONDAY RAINFALL...WILL
CONTINUE MENTION OF STREAM RISES IN THE HAZARDOUS WEATHER OUTLOOK.
AS THE UPPER LOW MOVES NORTHEAST OF THE AREA...MUCH COLDER AIR
WILL ENTER THE REGION...WITH PRECIP CHANGING OVER TO SNOW FOR MOST
AREAS WEDNESDAY. WITH TEMPERATURES REMAINING ABOVE FREEZING UNTIL
WEDNESDAY NIGHT...AND EXPECTED LIGHT SNOWFALL RATES...DO NOT
EXPECT SIGNIFICANT ACCUMULATION...WITH PERHAPS AN INCH OR SO ON
THE RIDGES AND ALONG THE I-80 CORRIDOR.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BUILD ACROSS THE AREA THURSDAY FOR DRY BUT
CHILLY CONDITIONS. MODELS HAVE BEEN CONSISTENT WITH A WEAK COLD
FRONT CLIPPING THE AREA LATE FRIDAY/FRIDAY NIGHT. WITH LIMITED
MOISTURE...WILL USE LOW END CHANCE POPS. DRY AND CHILLY CONDITIONS
ARE EXPECTED FOR THE WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
PER RECENT SURFACE AND RADAR DATA ALONG WITH HRRR AND NAM MODEL
OUTPUT, EXPECT FRONTAL RAIN BAND, NORTHEAST OF KENTUCKY LOW PRESSURE
CENTER TO REMAIN OVER MUCH OF THE UPPER OHIO VALLEY THROUGH 15Z,
BEFORE PIVOTING NORTHWESTWARD THE REST OF TODAY.
WITH THE RAIN BAND, THERE CAN BE PERIODS OF IFR THROUGH 15Z,
ALTHOUGH MVFR CONDITIONS WILL BE MORE PREVALENT. AS THE RAIN BAND
EXITS NORTHWEST, EXPECT VFR TO BECOME THE PREVALENT FLIGHT CONDITION
THIS AFTERNOON, EXCEPT FOR MAYBE KZZV AND KFKL.
OUTLOOK...MONDAY NIGHT THROUGH FRIDAY....
NORTHEASTWARD MOVING COLD FRONTAL BAND OF RAIN WILL PROVIDE RENEWED
RESTRICTIONS LATE TUESDAY MORNING INTO TUESDAY NIGHT. POST SYSTEM
WRAP AROUND SHOWERS OF RAIN AND SNOW MAY CAUSE ADDITIONAL SHORT
PERIODS OF RESTRICTIONS WEDNESDAY. AFTER VFR UNDER HIGH PRESSURE
THURSDAY, COLD FRONTAL SHOWERS OF RAIN OR SNOW MAY PROVIDE
RESTRICTIONS FRIDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1031 AM EST MON NOV 28 2011
.SYNOPSIS.../ISSUED AT 1031 AM/
PATCHES OF LIGHT LAKE EFFECT SNOW WILL EVENTUALLY TAPER OFF BY
LATE TODAY. HIGH PRESSURE MAKES A BRIEF APPEARANCE TODAY. SKIES
WILL REMAIN MOSTLY CLOUDY. MORE PRECIPITATION IS IN STORE FOR
PARTS OF THE NORTHERN LOWER PENINSULA TUESDAY INTO TUESDAY
NIGHT...MAINLY FOR AREAS SOUTHEAST OF GAYLORD. EASTERN UPPER WILL
PROBABLY STAY DRY THROUGH THIS PERIOD.
LOCKER/HALBLAUB
&&
.SHORT TERM.../ISSUED AT 1031 AM/...THIS AFTERNOON
...MOSTLY CLOUDY AND CHILLY WITH CONTINUING POTENTIAL FOR PATCHES
OF LIGHT SNOW NEAR THE COASTS THRU AFTN...
UPPER-LEVEL FLOW IS HIGHLY AMPLIFIED OVER N AMERICA...BUT
PROGRESSIVE OVER CANADA AND THE NRN USA. SHRTWV RIDGING IS BUILDING
OVER THE GTLKS IN ADVANCE OF THE NEXT TROF CURRENTLY MOVING THRU
MANITOBA-MONTANA. THE SRN USA FLOW IS MORE BLOCKY AND THE TAIL END
OF AN ANTICYCLONIC WAVE-BREAKING EVENT HAS RESULTED IN A CLOSED LOW
OVER THE TN VALLEY IN THE LAST 24 HRS.
AT THE SFC...YESTERDAY`S COLD FRONT /THAT HAS ESTABLISHED MUCH MORE
SEASONABLE TEMPS/ WAS ALONG THE APPALACHIANS WITH A SFC LOW OVER NRN
GA. HIGH PRES EXTENDED FROM OK TO THE GTLKS. THE NEXT INACTIVE COLD
FRONT WAS MOVING INTO THE NRN PLAINS.
CLOUDS: FOG/REFLECTIVITY PRODUCT OVERLAID WITH 925 MB ANALYSIS SHOWS
THAT MVFR STRATUS IS ASSOCIATED WITH THE LOW-LEVEL THERMAL TROF/COLD
POOL. EROSION OF BACK EDGE IS OCCURRING WITH WAA. INTERESTING TO
NOTE THAT THIS EDGE HAS ONLY PROGRESSED FROM WRN MN BORDER TO THE MS
RIVER IN THE LAST 24 HRS.
INITIAL VIS CHANNEL IMAGERY SHOWS BREAKS AND THIN SPOTS. THESE AND
ANY OTHER BREAKS THAT DEVELOP WILL FILL BACK-IN WITH THERMAL TROF
OVERHEAD. SO MAINTAINED A M/CLOUDY FCST FOR THE REST OF THE DAY AND
INCREASED SKYCOVER AFTER 15Z. THE ERN U.P. COULD TURN P/CLOUDY LATE
BUT IT WILL PROBABLY OCCUR JUST BEFORE SUNSET.
INTERESTING CLOUD MICROPHYSICS. STRATUS IS YIELDING PATCHES OF FINE
SNOW GRAINS. THE COLDEST TEMP /AT THE BASE OF THE INVERSION/ IS -7C.
UNSURE HOW FAR TO EXTEND THIS THRU THE DAY. CONDITIONS APPEAR
FAVORABLE FOR IT TO CONTINUE AND 3KM HRRR IS THE ONLY MODEL SHOWING
IT. SO EXPANDED THE THREAT THRU 21Z...MAINLY FOR IMMEDIATE LAKESHORE
COUNTIES BUT THERE COULD BE FLURRY FURTHER INLAND.
TEMPS: THEY`RE REALLY GOING NOWHERE...HOLDING STEADY. THEY`RE NOT
FOLLOWING THE FCST TEMP CURVE DUE TO CLOUD COVER. SO 3-5F WERE
TRIMMED OFF AFTN HIGHS FROM 4 AM APX FCST.
HALBLAUB
&&
.LONG TERM.../ISSUED AT 445 AM/...TONIGHT AND BEYOND
TONIGHT...THE HIGH PRESSURE GOES VIRTUALLY NO WHERE...REMAINING
OVER NRN LOWER...WHILE THE LOW PRESSURE FROM TENNESSEE AND THE
COLD FRONT OUT TO OUR WEST BEGIN TO CONVERGE ON THE GREAT LAKES.
THE SW WIND PICKS UP A BIT ACROSS NW LOWER AND EASTERN UPPER WITH
ADDITIONAL 925MB WARMING...WHICH SHOULD EAT AWAY AT THE
STRATOCU. HOWEVER...INCREASING HIGH CLOUDS FROM BOTH FEATURES
WILL RESULT IN INCREASING CLOUDINESS FOR WHEREVER IT DOES START OF
ON THE CLEARER SIDE OF THINGS. MODEL CONSENSUS SUGGESTS THAT A
DEEP ATLANTIC MOISTURE FEED INTO THE NORTHWARD PROGRESSING LOW
PRESSURE WILL GET WRAPPED AROUND INTO A TROWEL WHICH LIFTS NORTH
OF THE OHIO RIVER VALLEY NEAR DTX BY DAYBREAK. MEANWHILE...NEAR
THE SAGINAW BAY REGION DEFORMATION ZONE AND FGEN ALOFT SNEAKS IN
OVER THE FAR SE CWA FOR SOME MODEL SUGGESTED LIGHT RAIN
DEVELOPMENT. HOWEVER...ANTECEDENT EXTREMELY DRY AIR MASS WILL BE
DIFFICULT TO MOISTEN...ESPECIALLY WHEN CONSIDERING STRENGTHENING
FGEN AND SHARP CUT OFF TO THE NRN EDGE OF THE RAIN SHIELD. MODEL
SOUNDINGS DO NOT SUPPORT ANY PRECIPITATION...AND LOWERED THE
CHANCE FOR SEEING PRECIP...BUT DID LEAVE A SMALL CHANCE RIGHT
NEAR THE SAG BAY. LOW TEMPS WILL BE IN THE LOW 30S.
TUESDAY THROUGH WEDNESDAY...LOW PRESSURE WILL LIFT THROUGH THE
EASTERN GREAT LAKES AND DEEPEN WHILE PARENT UPPER CUT OFF LOW
WILL TRY AND PHASE TO SOME DEGREE WITH NRN STREAM ENERGY. UPSTREAM
COLD FRONT DROPS IN ACROSS NRN MICHIGAN AND MESHES WITH THE LOW
PRESSURE RESULTING IN STRENGTHENING NORTHERLY WINDS AND DRY
ADVECTION OUT OF EASTERN UPPER. MEANWHILE THE DEFORMATION/FGEN AND
TROWAL LIFTS UP INTO NE LOWER. EXACTLY HOW FAR NORTH THE SHARP
CUTOFF TO THE NRN EDGE OF THE PRECIPITATION MAKES IT...IS STILL A
BIT UNCLEAR. THAT SAID...FEEL THAT THE NW HALF OF THE CWA IS
LIKELY TO SEE NO PRECIPITATION...WHILE A GOOD CHUNK OF NE LOWER IS
GONNA GET A LITTLE DAMP. MODEL SUGGESTIONS OF WARM WEDGE OF AIR
ALOFT (TROWAL) MOVING IN OVER SFC TEMPS LOWERING TO 32F OR LOWER
TUESDAY NIGHT IN PARTS OF THE PRECIP SHIELD ARE MOST LIKELY NOT
GONNA HAPPEN. TEMPERATURES OVER THIS AREA WILL LIKELY REMAIN AT OR
JUST ABOVE FREEZING...AND ANY CHANCE OF NEW NAM SOUNDINGS
SUGGESTING SOME FREEZING RAIN ARE SMALL. HAVE CONTINUED THE THEME
OF RAIN AND SNOW...BUT LOWERED THE POTENTIAL SNOW AMOUNTS DUE TO A
WARMER SCENARIO/HIGHER SNOW/WATER RATIOS. MAYBE AN INCH AROUND THE
SAGINAW BAY. DUE TO THE UNCERTAINTY AND MARGINAL THERMAL REGIMES
WILL CONTINUE TO MENTION THE POTENTIAL FOR ACCUMULATING SNOW IN
THE HWOAPX. THE WEATHER IMPROVES INTO WEDNESDAY AS THE LOW
PRESSURE WORKS ITS WAY OUT OF THE EASTERN GREAT LAKES...TAKING THE
DEEPER MOISTURE AND FORCING OUT OF NE LOWER. OUTSIDE OF NE
LOWER...THE REMAINDER OF THE CWA WILL LIKELY BE UNDER AT LEAST
HIGH LEVEL CLOUDS. SKIES WILL BE CLEAREST ACROSS FAR WESTERN
CHIP/MACK COUNTIES. HIGHS WILL BE IN THE UPPER 30S TO AROUND 40
DEGREES AGAIN.
THURSDAY ONWARD...ONE NORTHERN STREAM SHORTWAVE STILL EXPECTED
THURS-THURS NIGHT FOR POSSIBLE CHANCE AT SNOW...WHILE A BETTER
SHOT MAY DEVELOP OVER THE WEEKEND. NOT MANY CHANGES IN THIS TIME
PERIOD.
SMD
&&
.MARINE.../ISSUED AT 1131 AM/
HIGH PRES IS OVER THE LAKES TODAY...RESULTING IN LIGHT WINDS AND
LOW SEAS. HALBLAUB
THE MAIN MARINE ISSUE WILL BE A LOW PRESSURE SYSTEM LIFTING
THROUGH THE EASTERN GREAT LAKES TUESDAY THROUGH WEDNESDAY. A TIGHT
PRESSURE GRADIENT IS ANTICIPATED WITH DEFINITE SMALL CRAFT
ADVISORIES ACROSS ALL NEARSHORES. THE GALE POTENTIAL IS BECOMING
MORE CERTAIN FOR PORTIONS OF THE NEARSHORES OF LAKE MICHIGAN AND
HURON...MAINLY SURROUNDING NORTHERN LOWER MICHIGAN.
SMD
&&
.AVIATION.../ISSUED AT 628 AM/...VALID FOR 12Z TAFS
WIDESPREAD MVFR CIGS IN STRATOCU TO START OUT THE DAY. THESE
CLOUDS EXTEND AS FAR BACK AS ALL OF WISCONSIN. THIS WILL BE THE
THEME OF THE DAY...AS MVFR CONDITIONS ARE EXPECTED TO PERSIST
THROUGH MOST OF THE DAY UNTIL WARM ADVECTION AND DEVELOPING LAND
BREEZES OUGHT TO BREAK APART THE SHIELD OF CLOUDS. DURING THIS
TIME WE WILL SEE AN INCREASE IN HIGH LEVEL CIRRUS WITH THE
APPROACH OF A COLD FRONT FROM THE WEST...AND A STRENGTHENING LOW
PRESSURE SYSTEM FROM THE SOUTH. THE PRESSURE GRADIENT TIGHTENS
LATE IN THE TAF PERIOD...WITH WINDY CONDITIONS EXPECTED OUT OF THE
NNE TUESDAY.
SMD
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...GALE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY AFTERNOON FOR
LHZ347>349.
LM...GALE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY AFTERNOON FOR
LMZ323-342-344>346.
LS...NONE.
&&
$$
WFO APX
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
630 AM EST MON NOV 28 2011
UPDATED AVIATION DISCUSSION FOR 12Z TAFS
.SYNOPSIS /ISSUED AT 514 AM/...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGING FROM
THE SW CONUS THROUGH THE UPPER MS VALLEY TO HUDSON BAY AND A CUTOFF
LOW OVER THE LOWER MS VALLEY. MAINLY ZONAL NRN STREAM FLOW
PREVAILED FROM THE EPAC THROUGH SRN CANADA AND THE NRN PLAINS. A
SHORTWAVE TROUGH EXTENDED FROM SRN SASK INTO NW MT WAS MOVING
STEADILY TO THE EAST. AT THE SFC...SRLY WINDS WERE INCREASING OVER
MN AND THE ERN DAKOTAS BTWN A TROUGH FROM MANITOBA TO THE WRN PLAINS
AND A RIDGE INTO THE WRN GREAT LAKES. IR 11-3.9 LOOP SHOWED THAT THE
BACK EDGE OF PERSISTENT LOW CLOUDS OVER UPPER MI...WI AND ERN MN WAS
ONLY MAKING SLOW OR LITTLE PROGRESS TO THE EAST. KINL/KMPX/KGRB
SOUNDINGS SHOWED MOIST LAYER TRAPPED BELOW A STRONG 900-850 MB
INVERSION. RADAR INDICATED THAT THE LIGHT LAKE EFFECT SNOW SHOWERS
OR FLURRIES OVER ERN LAKE SUPERIOR HAD DIMINISHED TO NO MORE THAN A
FEW FLURRIES FROM MUNISING EASTWARD.
&&
.DISCUSSION...
TODAY...NAM/RUC 925-900 MB RH PROGS SUGGEST THAT THE LOW CLOUDS
SHOULD DISSIPATE AND/OR DEPART TO THE EAST THIS MORNING AS LOW LEVEL
SW WINDS INCREASE. THIS WOULD LEAVE PARTLY TO MOSTLY SUNNY SKIES
THIS AFTERNOON AS MID/HIGH CLOUDS SUPPORTED BY WAA AHEAD OF THE
PLAINS TROUGH SPREAD INTO THE AREA. HOWEVER...SINCE THE MODELS HAVE
RECENTLY BEEN TOO EAGER TO REMOVE THE LOWER CLOUDS...EXPECT A DELAY
IN CLEARING MAY EXTEND INTO THE AFTERNOON. THIS SHOULD LIMIT MAX
TEMPS TO MAINLY THE MID 30S...WITH SOME UPPER 30S TO AROUND 40
READINGS AT LOCATIONS FAVORED BY SW DOWNSLOPE FLOW.
TONIGHT...THE SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WILL DRAG
A COLD FRONT/TROUGH THROUGH THE AREA. THE WEAK TO MODERATE QVECTOR
FORCING ACCOMPANYING THE TROUGH WILL REMAIN MAINLY NORTH OF THE CWA.
WITH LITTLE MOISTURE AVAILABLE...NO MEASURABLE PCPN IS EXPECTED.
KEPT TEMPS NEAR THE HIGHER END OF GUIDANCE AS CLOUDS WILL AGAIN KEEP
TEMPS FROM FALLING OFF TOO MUCH.
TUESDAY...STIFF NRLY WINDS WITH INFLUX OF LAKE MOISTURE AND
UPSLOPE FLOW WILL SUPPORT PERSISTENT LOWER CLOUDS OVER THE AREA.
ALTHOUGH THE SHALLOW LOWER CLOUD LAYER EXTENDING ONLY UP TO 900-850
TEMPS AROUND -6C MAY SUGGEST POTENTIAL FOR -FZDZ...A RELATIVELY DRY
SUB CLOUD LAYER WOULD NOT BE FAVORABLE.
TUE NIGHT INTO WED...WITH THE MID LEVEL AND SFC RIDGE BUILDING INTO
THE AREA...ALONG WITH DRY ADVECTION...CLEARING SHOULD TAKE OVER BY
LATE TUE AND LINGER INTO WED MORNING. SO...TEMPS NEAR CONSENSUS
GUIDANCE APPEARED REASONABLE WITH READINGS INTO THE UPPER TEENS
INLAND WEST AND MID 20S NEAR THE LAKES AND OVER THE ERN CWA. TEMPS
SHOULD REBOUND TO THE MID AND UPPER 30S WED.
WED NIGHT INTO THU...THE GFS/ECMWF/GEM SUGGEST THAT ANOTHER
SHORTWAVE AND FRONT MOVING THROUGH THE AREA ACCOMPANIED BY AT LEAST
MODERATE MID LEVEL FGEN WILL SUPPORT AN AREA OF LIGHT SNOW OVER THE
REGION. DIFFERENCES REMAIN WITH THE PLACEMENT/INTENSITY OF THE PCPN.
FOR NOW...ONLY CHANCE POPS WERE INCLUDED.
FRI...CAA IN THE WAKE OF THE FRONT DROPPING 850 MB TEMPS INTO THE
-12C TO -14C...PER GFS/ECMWF RANGE SHOULD GENERATE LES INTO EARLY
FRI FOR NW FLOW SNOWBELTS. ANY LES WOULD BE SHORTLIVED AS THE
PROGRESSIVE PATTERN WOULD LIKELY BRING WAA QUICKLY BACK INTO THE
AREA BY THE END OF THE WEEK.
INTO THE WEEKEND...
MODELS SHOW GENERAL TROUGHING PATTERN INTO THE CNTRL CONUS.
HOWEVER...SIGNIFICANT DIFFERENCES EMERGE REGARDING WHETHER THE DRIER
NRN STREAM WILL DOMINATE WITH MAINLY LES CHANCES (GFS) OR POSSIBLE
PHASING WITH SRN STREAM COULD BRING MORE SUBSTANTIAL MOISTURE/SNOW
INTO THE AREA (ECMWF). FOR NOW...THE FCST LEANS TOWARD THE GFS
SCENARIO WITH TEMPS FALLING INTO THE UPPER 20S AND LOWER 30S BY SUN
WITH LES CHANCES...TYPICAL FOR EARLY WINTER.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
EXPECT PERSISTENT MVFR CIGS TO GRADUALLY GIVE WAY TO VFR CONDITIONS
W-E AS WARMER AND DRIER AIR FROM THE W MAKES ONLY SLOW PROGRESS INTO
THE UPR GRT LKS. IFR CIGS ARE PSBL EARLY AT IWD WITH SHALLOWER INVRN
BASE. ALTHOUGH A COLD FNT WL SWING ACRS THE AREA TNGT...THE TRAILING
AIRMASS IS RELATIVELY WARM. SO THE USUAL LK EFFECT CLDS THAT MIGHT
PLAGUE THE SITES THIS TIME OF YEAR WITH A WSHFT TO THE NNW BEHIND
THE FNT WL LIKELY BE ABSENT OR AT LEAST LESS WDSPRD THAN USUAL. BUT
GUSTY WINDS ARE LIKELY UNDER SHARPENING PRES GRADIENT.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
EXPECT INCREASNIG SW WINDS UP TO 30 KTS TODAY UNDER SHARPENING PRES
GRADIENT BETWEEN DEPARTING SFC HI OVER THE CENTRAL GREAT LAKES AND
AN APPROACHING COLD FRONT. THERE MAY EVEN BE A FEW GALE FORCE GUSTS
BETWEEN ISLE ROYALE AND THE KEWEENAW WHERE TERRAIN INFLUENCES WILL
ACCENTUATE THIS FLOW. AFTER THIS FRONT PASSES LAKE SUPERIOR
TONIGHT...THERE WILL BE WSHFT TO THE N. DEPENDING ON HOW QUICKLY A
LO PRES SYSTEM DEVELOPS IN THE OHIO VALLEY AND HOW FAR THIS
DISTURBANCE TRACKS TO THE W...MARGINAL GALES ARE POSSIBLE OVER THE
CENTRAL AND EASTERN PARTS OF THE LAKE AS THE PASSAGE OF COLDER AIR
OVER THE RELATIVELY WARM LAKE WATERS ENHANCES MIXING OF STRONGER
WINDS ALOFT TO THE SURFACE. THESE STRONGER WINDS WILL DIMINISH W-E
AND SHIFT MORE TO THE WNW TUE NIGHT THRU WED NIGHT AS HI PRES BUILDS
TOWARD THE UPPER MIDWEST. LOOK FOR ANOTHER WSHFT TO THE N-NW ON THU
FOLLOWING THE PASSAGE OF ANOTHER TROF ACROSS LAKE SUPERIOR. ONCE THE
TRAILING HI SHIFTS TO THE S ON FRI...A STRONGER SW FLOW WILL
REDEVELOP IN THIS CHANGEABLE WEATHER PATTERN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
514 AM EST MON NOV 28 2011
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGING FROM
THE SW CONUS THROUGH THE UPPER MS VALLEY TO HUDSON BAY AND A CUTOFF
LOW OVER THE LOWER MS VALLEY. MAINLY ZONAL NRN STREAM FLOW PREVAILED
FROM THE EPAC THROUGH SRN CANADA AND THE NRN PLAINS. A SHORTWAVE
TROUGH EXTENDED FROM SRN SASK INTO NW MT WAS MOVING STEADILY TO THE
EAST. AT THE SFC...SRLY WINDS WERE INCREASING OVER MN AND THE ERN
DAKOTAS BTWN A TROUGH FROM MANITOBA TO THE WRN PLAINS AND A RIDGE
INTO THE WRN GREAT LAKES. IR 11-3.9 LOOP SHOWED THAT THE BACK EDGE
OF PERSISTENT LOW CLOUDS OVER UPPER MI...WI AND ERN MN WAS ONLY
MAKING SLOW OR LITTLE PROGRESS TO THE EAST. KINL/KMPX/KGRB SOUNDINGS
SHOWED MOIST LAYER TRAPPED BELOW A STRONG 900-850 MB INVERSION.
RADAR INDICATED THAT THE LIGHT LAKE EFFECT SNOW SHOWERS OR FLURRIES
OVER ERN LAKE SUPERIOR HAD DIMINISHED TO NO MORE THAN A FEW FLURRIES
FROM MUNISING EASTWARD.
&&
.DISCUSSION...
TODAY...NAM/RUC 925-900 MB RH PROGS SUGGEST THAT THE LOW CLOUDS
SHOULD DISSIPATE AND/OR DEPART TO THE EAST THIS MORNING AS LOW LEVEL
SW WINDS INCREASE. THIS WOULD LEAVE PARTLY TO MOSTLY SUNNY SKIES THIS
AFTERNOON AS MID/HIGH CLOUDS SUPPORTED BY WAA AHEAD OF THE PLAINS
TROUGH SPREAD INTO THE AREA. HOWEVER...SINCE THE MODELS HAVE RECENTLY BEEN
TOO EAGER TO REMOVE THE LOWER CLOUDS...EXPECT A DELAY IN CLEARING MAY
EXTEND INTO THE AFTERNOON. THIS SHOULD LIMIT MAX TEMPS TO MAINLY THE
MID 30S...WITH SOME UPPER 30S TO AROUND 40 READINGS AT LOCATIONS
FAVORED BY SW DOWNSLOPE FLOW.
TONIGHT...THE SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WILL DRAG
A COLD FRONT/TROUGH THROUGH THE AREA. THE WEAK TO MODERATE QVECTOR
FORCING ACCOMPANYING THE TROUGH WILL REMAIN MAINLY NORTH OF THE CWA.
WITH LITTLE MOISTURE AVAILABLE...NO MEASURABLE PCPN IS EXPECTED.
KEPT TEMPS NEAR THE HIGHER END OF GUIDANCE AS CLOUDS WILL AGAIN KEEP
TEMPS FROM FALLING OFF TOO MUCH.
TUESDAY...STIFF NRLY WINDS WITH INFLUX OF LAKE MOISTURE AND
UPSLOPE FLOW WILL SUPPORT PERSISTENT LOWER CLOUDS OVER THE AREA.
ALTHOUGH THE SHALLOW LOWER CLOUD LAYER EXTENDING ONLY UP TO 900-850
TEMPS AROUND -6C MAY SUGGEST POTENTIAL FOR -FZDZ...A RELATIVELY DRY
SUB CLOUD LAYER WOULD NOT BE FAVORABLE.
TUE NIGHT INTO WED...WITH THE MID LEVEL AND SFC RIDGE BUILDING INTO
THE AREA...ALONG WITH DRY ADVECTION...CLEARING SHOULD TAKE OVER BY
LATE TUE AND LINGER INTO WED MORNING. SO...TEMPS NEAR CONSENSUS
GUIDANCE APPEARED REASONABLE WITH READINGS INTO THE UPPER TEENS
INLAND WEST AND MID 20S NEAR THE LAKES AND OVER THE ERN CWA. TEMPS
SHOULD REBOUND TO THE MID AND UPPER 30S WED.
WED NIGHT INTO THU...THE GFS/ECMWF/GEM SUGGEST THAT ANOTHER
SHORTWAVE AND FRONT MOVING THROUGH THE AREA ACCOMPANIED BY AT LEAST
MODERATE MID LEVEL FGEN WILL SUPPORT AN AREA OF LIGHT SNOW OVER THE
REGION. DIFFERENCES REMAIN WITH THE PLACEMENT/INTENSITY OF THE PCPN.
FOR NOW...ONLY CHANCE POPS WERE INCLUDED.
FRI...CAA IN THE WAKE OF THE FRONT DROPPING 850 MB TEMPS INTO THE
-12C TO -14C...PER GFS/ECMWF RANGE SHOULD GENERATE LES INTO EARLY
FRI FOR NW FLOW SNOWBELTS. ANY LES WOULD BE SHORTLIVED AS THE
PROGRESSIVE PATTERN WOULD LIKELY BRING WAA QUICKLY BACK INTO THE
AREA BY THE END OF THE WEEK.
INTO THE WEEKEND...
MODELS SHOW GENERAL TROUGHING PATTERN INTO THE CNTRL CONUS.
HOWEVER...SIGNIFICANT DIFFERENCES EMERGE REGARDING WHETHER THE DRIER
NRN STREAM WILL DOMINATE WITH MAINLY LES CHANCES (GFS) OR POSSIBLE
PHASING WITH SRN STREAM COULD BRING MORE SUBSTANTIAL MOISTURE/SNOW
INTO THE AREA (ECMWF). FOR NOW...THE FCST LEANS TOWARD THE GFS
SCENARIO WITH TEMPS FALLING INTO THE UPPER 20S AND LOWER 30S BY SUN
WITH LES CHANCES...TYPICAL FOR EARLY WINTER.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
NORTH TO NORTHWEST FLOW HAS HELPED KEEP MVFR CIGS IN AT ALL
TERMINALS. WITH LTL MOVEMENT IN CLEARING LINE OVER CENTRAL MN...IT
WILL TAKE SOME TIME FOR CLEARING TO MOVE INTO UPPER MICHIGAN. IN
FACT...CLEARING WILL PROBABLY NOT OCCUR UNTIL LATE MORNING OR AT
LEAST UNTIL AFTER SUNRISE WHEN SW WINDS PICK UP ON BACKSIDE OF HIGH
PRESSURE.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
EXPECT INCREASNIG SW WINDS UP TO 30 KTS TODAY UNDER SHARPENING PRES
GRADIENT BETWEEN DEPARTING SFC HI OVER THE CENTRAL GREAT LAKES AND
AN APPROACHING COLD FRONT. THERE MAY EVEN BE A FEW GALE FORCE GUSTS
BETWEEN ISLE ROYALE AND THE KEWEENAW WHERE TERRAIN INFLUENCES WILL
ACCENTUATE THIS FLOW. AFTER THIS FRONT PASSES LAKE SUPERIOR
TONIGHT...THERE WILL BE WSHFT TO THE N. DEPENDING ON HOW QUICKLY A
LO PRES SYSTEM DEVELOPS IN THE OHIO VALLEY AND HOW FAR THIS
DISTURBANCE TRACKS TO THE W...MARGINAL GALES ARE POSSIBLE OVER THE
CENTRAL AND EASTERN PARTS OF THE LAKE AS THE PASSAGE OF COLDER AIR
OVER THE RELATIVELY WARM LAKE WATERS ENHANCES MIXING OF STRONGER
WINDS ALOFT TO THE SURFACE. THESE STRONGER WINDS WILL DIMINISH W-E
AND SHIFT MORE TO THE WNW TUE NIGHT THRU WED NIGHT AS HI PRES BUILDS
TOWARD THE UPPER MIDWEST. LOOK FOR ANOTHER WSHFT TO THE N-NW ON THU
FOLLOWING THE PASSAGE OF ANOTHER TROF ACROSS LAKE SUPERIOR. ONCE THE
TRAILING HI SHIFTS TO THE S ON FRI...A STRONGER SW FLOW WILL
REDEVELOP IN THIS CHANGEABLE WEATHER PATTERN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
930 AM EST MON NOV 28 2011
.SYNOPSIS...
A STALLED FRONTAL BOUNDARY OVER WESTERN NEW YORK AND PENNSYLVANIA
MAY TRIGGER SOME SHOWERS OVER THE FINGER LAKES AND MOHAWK VALLEY
INTO TUESDAY. LOW PRESSURE MOVING NORTHWARD FROM THE TENNESSEE
VALLEY WILL PUSH RAIN INTO THE REGION TUESDAY NIGHT AND WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 925 AM...MINOR TWEEKS TO CRNT FCST. CDFNT REMAINS
DRAPED ACRS THE BGM CWA WITH 3-HRLY PRES RISES OF 3-4 MB CNTRD
OVER NRN NY. FNT CONTINUE TO MAKE SLOW SWD PROGRESS...WITH ELM NOW
SHOWING A LGT NE WIND. THE RUC APPEARS TO HAVE THE BEST HANDLE ON
THE SITN...SUGGESTING THE FNT MAY CONTINUE TO SAG SLOWLY SWD THIS
AFTN INTO THE REMAINDER OF THE SRN TIER BEFORE LIFTING NWD OVRNGT. WILL
KEEP CHC POPS FOR -SHRA ALONG AND N OF THE FNT FOR THIS AFTN. ACRS
NE PA...SOME BREAKS OF SUNSHINE AND TEMPS ARND OR INTO THE L60S.
PREV BLO...
FNTL BNDRY REMAINS NEARLY STATIONARY OVER THE NW CORNER OF THE
FCST AREA AND WILL REMAIN THE FOCUS OF LGT SHWRS THRU THE DAY.
CRNTS AND RADAR SHOW ONLY VERY LGT RAIN IN THE AREA ATTM...AND DO
NOT XPCT THE INTENSITY TO CHG MUCH AT ALL DURING THE DAY...SO
DESPITE THE LACK OF MVMT...EXCESSIVE RAINFALL AMTS NOT XPCTD.
LATEST SYR TEMPS 62 SO A TRICKY TEMP FCST IN THE GRIDS AS A NON
DIURNAL TEMPS TREND IS XPCTD THIS MRNG AND THIS AFTN AS THE ACTUAL
SFC BNDRY DRFTS SOUTH AND BRINGS COOLER AIR TO THE NW ZONES. NAM12
TEMP FCST SEEMED CLOSEST TO CRNTS AND CAPTURED THE COOLING TREND
UP NORTH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
MODELS CONT TO BE IN GOOD AGREEMENT ON THE UPR LOW OVER THE ERN
US. THIS BRINGS A FAIRLY HIGH CONFIDENCE FCST DESPITE THE NRMLY
UNPREDICTABLE NATURE OF CUT OFF OR CLSD LOWS. AS LOW DEEPENS AND
LIFTS NWRD TNGT...OLD BNDRY OVER WRN NY IS FRCD BACK WWRD AND
BRIEF RDGG RETURNS TO THE FCST AREA. THIS SHD KEEP THE FCST AREA
DRY THRU TUE AHD OF THE UPR LOW.
LOW APRCHS TUE NGT AND INITIAL BAND OF RAIN MVES INTO THE AREA.
DEEP SLY FLOW WITH A SUBTROPICAL CONNECTION WILL BRING A PD OF
HEAVY RAIN...MOST LIKELY BETWEEN 00Z AND 06Z WED. GOOD NEWS IS
THAT THE SYSTEM IS PROGRESSIVE SO RAIN DURATION WILL BE SHORT AND
SHD LIMIT THE CNCRN FOR ANY FLOODING ISSUES. LGTR RAIN WILL CONT
LTR TUE NGT INTO WED AS THE UPR LOW LIFTS THRU WRN NY. COOLER AIR
WRAPPING ARND THE BASE OF THE LOW WILL BEGIN THE RETURN TO MORE
SEASONABLE TEMPS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
4 AM UPDATE...THE AREA OF LOW PRESSURE MENTIONED ABOVE WILL
CONTINUE TO MOVE INTO EASTERN QUEBEC WEDNESDAY NIGHT. ON THE
BACKSIDE OF THE LOW ENOUGH COOL AIR AND PRECIP MAY LINGER AROUND
FOR A BRIEF SHOT OF LIGHT SNOW ESPECIALLY IN NY STATE. STILL SOME
UNCERTAINTY WITH THIS SCENARIO WITH THE GFS MORE MILD THAN THE
EURO WHICH WOULD INDICATE MORE OF A MIX WITH RAIN. WE MAY SEE A
BRIEF WINDOW OF LAKE EFFECT LATER WEDNESDAY NIGHT ESPECIALLY IF
THE COLDER EURO IS CORRECT...BEFORE BUILDING HEIGHTS BRING US DRY
WEATHER THURSDAY.
ANOTHER BRIEF SHOT OF CHILLY AIR LATER FRIDAY AND FRIDAY NIGHT MAY
BRING US A PERIOD OF SCT. SNOW SHOWERS WITH LAKE SNOWS POSSIBLE
BEHIND IT. MOST OF THE UPCOMING WEEKEND LOOKS DRY BUT PLENTY OF
UNCERTAINTY EXISTS WITH THE EVOLUTION OF A COLD FRONT LATER SUNDAY
INTO EARLY NEXT WEEK. THE GFS IS THE FASTER SOLUTION BRINGING IN
PRECIP BY LATE SUNDAY WHILE ALLOWING FOR COLDER AIR TO MOVE IN AS
EARLY AS SUNDAY NIGHT. THE EURO HOLDS THE FRONT BACK...KEEPS THE
WEEKEND DRY...AND WOULD KEEP US ALL LIQUID THROUGH MONDAY. HPC
GUIDANCE LEANS TOWARD THE EURO AND GIVEN THAT THE GFS IS HAVING
RUN TO RUN CONSISTENCY ISSUES (18Z GFS SUPPORTS SLOWER
SOLUTION...0Z RUN DOES NOT)...MORE CONFIDENT WITH THE EURO. WITH
THAT IN MIND WILL KEEP THE WEEKEND DRY AND WITH 850S ABOVE 0C
THROUGH MONDAY...ANY PRECIP DURING THIS TIME WILL BE IN THE LIQUID
FORM.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
645 AM UPDATE...A COLD FRONT ACROSS OUR NORTHERN TERMINALS NOW
WILL PRODUCE IFR TO MVFR CIGS THROUGH EARLY AFTERNOON AT KSYR AND
KRME. MVFR VSBYS ARE ALSO POSSIBLE THIS MORNING IN SHOWERS. CIGS
WILL COME UP A BIT THIS AFTERNOON BUT IT WON`T BE UNTIL NEAR 0Z
TONIGHT THAT A RETURN TO VFR IS EXPECTED.
FARTHER SOUTH WITH THE REST OF THE TERMINALS BEING SOUTH OF THE
FRONT AND EXPECTED TO STAY THAT WAY...RESTRICTION FORECAST MUCH
TOUGHER. MVFR CIGS APPEAR MOST LIKELY AT KAVP SINCE WE HAVE
ALREADY HAD THEM. HOWEVER BASED ON OBS THINK THIS WILL CONTINUE TO
BE AN ON AND OFF AND THUS A TEMPO GROUP WILL COVER IT. AT KELM AND
KBGM...WHILE CIGS WILL LIKELY LOWER...FEEL BOTH TERMINALS ARE JUST
FAR ENOUGH AWAY TO KEEP CIGS AT VFR. AT KITH...WITH THE SITE BEING
CLOSEST TO THE FRONT (OUTSIDE OF THE FAR NORTHERN
TERMINALS)...FELT AT LEAST A TEMPO MVFR GROUP WAS WARRANTED THIS
MORNING. AS HEIGHTS BUILD CIGS SHOULD IMPROVE THIS AFTERNOON.
VFR IS EXPECTED EARLY TONIGHT BUT MVFR TO IFR CIGS MAY RETURN LATE
TONIGHT ACROSS THE SOUTHERN TERMINALS WITH MOISTURE TRAPPED
UNDERNEATH AN INVERSION.
OUTLOOK...
MON NGT...IFR/MVFR. PERIODS OF RAIN AND FOG.
TUE THRU THU...PATCHY MVFR IN SCT -SHRA. SCT -SHSN AND MVFR/BRIEF
IFR POSSIBLE BEGINNING WED.
FRI...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
SHORT TERM...DGM
LONG TERM...HEDEN
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
654 AM EST MON NOV 28 2011
.SYNOPSIS...
LOW PRESSURE WILL TRACK NORTH NORTHEAST ALONG A STALLED FRONT
WHICH WILL CONTINUE THE WET WEATHER ACROSS THE AREA. THE LOW WILL
MOVE ACROSS THE REGION ON TUESDAY. COLD AIR WRAPPING IN BEHIND THE
LOW WILL CHANGE LINGERING RAIN SHOWERS OVER TO SNOW SHOWERS BEFORE
THE PRECIPITATION ENDS ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ALTHOUGH THERE HAVE BEEN SOME BREAKS IN THE PRECIPITATION...RAIN
CONTINUES PRETTY MUCH AREA WIDE WITH PLENTY MORE UPSTREAM. AS THE
DAY PROGRESSES...LOW PRESSURE WILL APPROACH AND PULL THE OLD FRONT
BACK WEST INTO THE FORECAST AREA. THIS WILL ALSO ALLOW THE MAIN
PRECIPITATION AXIS TO SHIFT WEST SLIGHTLY. THERE SHOULD BE SOME
DRYING IN THE EASTERN COUNTIES WHERE THE FRONT PASSES AGAIN. BUT
NOT CONVINCED THAT IT WILL BE AS SHARP A CUT OFF IN PRECIPITATION
AS THE NAM AND RUC ARE SUGGESTING. HOWEVER IT SHOULD BE ENOUGH
FOR TEMPERATURES TO WARM MORE IN THOSE LOCATIONS THAN POINTS TO
THE WEST.
APPEARS THAT RAINFALL AMOUNTS WILL BE SLIGHTLY HIGHER IN THE TRI-
STATE AREA. BUT EVEN THERE IT SHOULD BE LESS THAN AN INCH IN A
MOSTLY LIGHT STEADY RAIN. THIS COULD LEAD TO SOME PONDING PROBLEMS
BUT POTENTIAL FOR SIGNIFICANT FLOODING DOES NOT LOOK PARTICULARLY
HIGH AT THIS POINT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
LOW PRESSURE WILL OCCLUDE AS IT APPROACHES THE REGION TONIGHT AND
LIFTS ACROSS THE AREA TOMORROW. RAIN WILL CONTINUE UNTIL DRY AIR
THAT HAS WRAPPED INTO THE SYSTEM PUSHES NORTH TUESDAY AFTERNOON
AND EVENING. THERE COULD BE A HEAVIER BURST OF RAIN ALONG AND
AHEAD OF THE OCCLUDED FRONT/LOW BUT FOR THE MOST PART THIS SHOULD
BE A CONTINUATION OF LIGHT STEADY RAIN. THERE COULD EVENTUALLY END
UP BEING SOME MINOR AREAL FLOOD ISSUES. ALSO RIVERS WILL RISE IN
RESPONSE TO THE RAINFALL WITH THE POTENTIAL FOR A FEW POINTS TO GO
INTO FLOOD. THIS HEIGHTEN FLOOD POTENTIAL STILL APPEARS TO BE A
DAY OUT. SO WILL CONTINUE TO HIGHLIGHT THIS IN THE HWO.
PRECIPITATION AND COLDER AIR WILL WRAP BACK ACROSS THE AREA
TUESDAY NIGHT. THIS WILL RESULT IN RAIN SHOWERS CHANGING TO SNOW
SHOWERS. THERE COULD BE SOME LIGHT ACCUMULATIONS PARTICULARLY ON
GRASSY SURFACES. AN INCH OR SO IS POSSIBLE IN THE FAR NORTHWEST
COUNTIES WHICH WILL BE NEAR A DEFORMATION ZONE AND THUS GREATER
PRECIPITATION AMOUNTS. SNOW SHOWERS WILL CONTINUE INTO WEDNESDAY
AS A SECONDARY TROUGH ROTATES AROUND THE DEPARTING LOW. CONDITIONS
WILL IMPROVE BY WEDNESDAY AFTERNOON WITH CLEARING WORKING IN FROM
THE WEST.
TEMPERATURES WILL BE CHALLENGING PARTICULARLY TONIGHT AND TUESDAY
WITH THE APPROACH AND PASSAGE OF THE LOW/OCCLUDED FRONT. EXPECT A
MILD NIGHT WITH TEMPERATURES RISING IN SOME LOCATIONS. THEN COLDER
AIR WILL OVERSPREAD THE REGION ON TUESDAY RESULTING IN MORNING
HIGHS AND FALLING TEMPERATURES. HAVE GONE SLIGHTLY ABOVE GUIDANCE
FOR LOWS TUESDAY NIGHT AND USED A MOS BLEND ON WEDNESDAY WITH COLD
ADVECTION AND MOSTLY CLOUDY SKIES NOT ALLOWING FOR MUCH OF A WARM
UP.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL BUILD IN FOR THE BEGINNING OF THE PERIOD. A
WEAK FRONT WILL SLIDE BY TO THE NORTH ON FRIDAY. MODELS HAVE COME
INTO AGREEMENT THAT THERE IS LIMITED PRECIPITATION POTENTIAL AT
BEST WITH THIS BOUNDARY. ANOTHER HIGH WILL QUICKLY TRAVERSE THE
AREA ON SATURDAY. THEN ANOTHER FRONT WILL MOVE IN FOR SUNDAY. BUT
IT APPEARS THAT THIS LATTER BOUNDARY WILL BE ABLE TO TAP MORE
MOISTURE. SO HAVE INCLUDED CHANCE POPS THEN.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AN AREA OF LOW PRESSURE SOUTH OF THE TAF SITES WILL MOVE NORTH
TODAY AND TONIGHT. MVFR TO IFR CONDITIONS CAN BE EXPECTED FOR MOST OF THE
TAF PERIOD ALTHOUGH A BRIEF PERIOD OF VFR CONDITIONS WILL BE
POSSIBLE. WIDESPREAD RAIN WILL CONTINUE THROUGH THE DAY TODAY.
SOME DRIER AIR WILL TRY TO WORK INTO EASTERN TAF SITES FOR A FEW
HOURS EARLY TONIGHT HOWEVER PRECIPITATION WILL QUICKLY FILL BACK
INTO THE AREA. A FEW WIND GUSTS UPWARDS OF 18 TO 20 KNOTS WILL BE
POSSIBLE TODAY AS WELL. THE AREA OF LOW PRESSURE WILL BEGIN TO
MOVE ACROSS THE SOUTHERN TAF SITES LATE IN THE TAF PERIOD. THIS
WILL ALLOW WINDS TO CHANGE DIRECTION AND FOR CIGS TO BEGIN TO
IMPROVE SLIGHTLY.
OUTLOOK...MVFR/IFR CIGS/VSBYS THROUGH WEDNESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...NOVAK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
543 AM CST MON NOV 28 2011
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT
310 AM CST MON NOV 28 2011
THE MAIN STORIES IN THE SHORT TERM ARE WITH THE PESKY STRATUS
THAT IS CURRENTLY DRAPED OVER MUCH OF THE REGION ALONG WITH THE
CHANCES FOR A LIGHT ACCUMULATION OF SNOW ON THURSDAY.
CURRENTLY...A SURFACE RIDGE OF HIGH PRESSURE EXTENDS FROM THE
SOUTHERN PLAINS THROUGH SOUTHEAST MINNESOTA AND LAKE SUPERIOR. A
STUBBORN LOW LEVEL STRATUS DECK REMAINS IN PLACE ACROSS MUCH OF
THE REGION ALONG THE EASTERN PERIPHERY OF THIS RIDGE. THE WESTERN
EDGE OF THIS CLOUD SHIELD HAS STARTED TO DRIFT EASTWARD OVERNIGHT
ACROSS EASTERN MINNESOTA AND SHOULD COME THROUGH THE FORECAST
AREA FROM WEST TO EAST TODAY. THE AREA OF LEAST CONFIDENCE IN THE
CLEARING OCCURRING IS IN FAR NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN AS THE STRATUS HAS BEEN SLOW TO MOVE IN CENTRAL IOWA.
THE 28.00Z NAM AND GFS APPEAR TO HAVE INITIALIZED TOO LOW ON THE
RH UNDER THE 900MB INVERSION...BUT THE 28.05Z RUC SEEMS TO HAVE A
BETTER HANDLE ON THE LOW LEVEL MOISTURE. THUS...HAVE GONE WITH A
PESSIMISTIC BLEND OF THE RUC AND PURE IR SATELLITE EXTRAPOLATION
TO GET THE CLEARING TREND DOWN. THIS CLOUD COVER WILL HAVE AN
IMPACT ON TEMPERATURES TODAY WITH THE HIGHEST VALUES TO THE
NORTHWEST WHERE THE SUN WILL BE OUT LONGER.
AFTER A BRIEF CLEAR PERIOD GOING INTO THE EVENING...MID TO HIGH
LEVEL CLOUD COVER WILL BE ON THE INCREASE AS A MID LEVEL TROUGH
NEAR SASKATCHEWAN DROPS SOUTHEAST INTO THE REGION. AS THIS TROUGH
INTERACTS WITH A CUTOFF LOW IN THE SOUTHEASTERN US IT WILL LOSE
SOME OF ITS BETTER FORCING WITH PV ADVECTION SHOWING A RAPID
DECREASE. WHILE PRECIPITATION LOOKS UNLIKELY...THIS TROUGH WILL
BRING A COLD FRONT ALONG WITH IT THAT WILL TRACK THROUGH TONIGHT.
WITH A SURFACE LOW TRACKING TO THE NORTH THROUGH THE OHIO RIVER
VALLEY AND A RIDGE OF HIGH PRESSURE FOLLOWING THE COLD FRONT...THE
UPPER MISSISSIPPI RIVER VALLEY WILL BE STUCK IN BETWEEN THESE TWO
FEATURES WITH A TIGHTENING PRESSURE GRADIENT. AS A RESULT...WIND
GUSTS OF 20-30KT WILL BE POSSIBLE ON TUESDAY...PARTICULARLY ACROSS
NORTHEAST IOWA AND SOUTHWEST WISCONSIN WHERE THE GRADIENT WILL BE
THE TIGHTEST.
THIS RIDGE OF HIGH PRESSURE WILL GRADUALLY SLIDE EASTWARD INTO THE
REGION WEDNESDAY INTO EARLY THURSDAY AND PROVIDE FOR SOME FAIRLY
COOL TEMPERATURES WITH LOWS IN THE TEENS. THE NEXT FEATURE OF NOTE IS
WITH A MID LEVEL TROUGH THAT IS EXPECTED TO DROP INTO THE REGION
ON THURSDAY. OVER THE PAST FEW DAYS...THE MODELS HAVE BEEN PRETTY
LOW ON PRODUCING ANY QPF OUT OF THIS FEATURE. HOWEVER...THE LATEST
TREND IS TO BE MUCH STRONGER WITH THIS MID LEVEL FEATURE AND
THEY SHOW QUITE A BIT OF QG FORCING WITH TROUGH. TEMPERATURES
WOULD BE COLD ENOUGH TO SUPPORT ALL SNOW ALONG AND BEHIND THE COLD
FRONT WHERE THE PRECIPITATION IS EXPECTED TO FORM. THIS LOOKS TO
BE A FAIRLY QUICK HITTER WITH LESS THAN A 6 HOUR WINDOW OF SEEING
THE SNOWFALL...SO TOTALS SHOULD BE FAIRLY LIGHT IF THIS DOES TAKE
SHAPE WITH THE SNOW ENDING THURSDAY NIGHT AS THE FORCING DROPS TO
THE SOUTHEAST OF THE REGION.
.LONG TERM...FRIDAY THROUGH SUNDAY NIGHT
310 AM CST MON NOV 28 2011
AFTER A RIDGE OF HIGH PRESSURE MOVES THROUGH ON FRIDAY...THE FOCUS
WILL BE ON THE WEEKEND AND WHETHER PRECIPITATION WILL FILL IN FROM
THE SOUTHWEST AS THE 27.00Z AND 26.12Z ECMWF IS SUGGESTING. THE
27.00Z SHOWS THE MID LEVEL CUT OFF LOW OVER THE FOUR CORNERS
REGION GETTING PICKED UP INTO THE NEXT TROUGH THAT TRACKS THROUGH
THE NORTHERN PLAINS SATURDAY INTO SUNDAY. THE 27.00Z
GFS...HOWEVER...KEEPS THIS LOW OUT OVER THE DESERT AND BRINGS THE
NORTHERN STREAM TROUGH THROUGH A LITTLE LESS AMPLIFIED. WITH A
COLD FRONT STALLED OUT JUST TO THE SOUTHEAST...PRECIPITATION IS
EXPECTED TO DEVELOP IN THE VICINITY OF IT AS THIS WAVE GETS PICKED
UP. TEMPERATURES SHOULD BE COLD ENOUGH TO SUPPORT ALL SNOW...SO
THIS SYSTEM WILL HAVE TO BE MONITORED FOR TRENDS AS THE GFS WOULD
SUGGEST THAT CONDITIONS WOULD BE DRY UNTIL SUNDAY NIGHT WHEN A
SYSTEM DROPS OUT OF SOUTHWESTERN CANADA.
&&
.AVIATION...THROUGH 12Z TUESDAY
543 AM CST MON NOV 28 2011
STUBBORN IFR/MVFR STRATUS HANGING TOUGH THIS MORNING AS HIGH
PRESSURE RIDGE AXIS OVERHEAD KEEPS MOISTURE TRAPPED UNDER THE
ASSOCIATED SUBSIDENCE INVERSION. MODELS CONTINUE TO SHOW THE RIDGE
AXIS SHIFTING SLOWLY SOUTHEAST OF THE AREA THIS AFTERNOON. SOUTHWEST
WINDS ON THE BACKSIDE OF THE HIGHS WILL HOPEFULLY AID IN
MIXING/ERODING THE STRATUS AT KRST AROUND 16Z AND AT KLSE AROUND
20Z. NEXT CONCERN WILL BE COLD FRONTAL PASSAGE TONIGHT AND BRISK
POST-FRONTAL NORTH WINDS THROUGH TUESDAY. EXPECTING NORTH WINDS TO
PICK UP AFTER MIDNIGHT AS COLD PUSH AND PRESSURE GRADIENT INCREASES
ACROSS THE AREA WITH GUSTS IN THE 20 TO 25KT RANGE. ALSO...SOME
INDICATIONS IN THE MODELS THAT A BAND OF SCATTERED TO BROKEN
STRATOCUMULUS MAY FORM BEHIND THE FRONT AFT 03Z. FOR NOW...WENT WITH
SCT020 AT KRST AND SCT025 AT KLSE...BUT MAY HAVE TO WATCH FOR
POTENTIAL MVFR CEILINGS. WILL PASS THIS CONCERN TO THE DAY SHIFT FOR
THE 18Z TAF ISSUANCE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
310 AM CST MON NOV 28 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...DAS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
420 PM EST MON NOV 28 2011
.SYNOPSIS...
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW PROGRESSIVE FLOW ACROSS SRN
CANADA...FEATURING A WEAK RIDGE OVER SW CANADA...A SHORTWAVE TROF
OVER MANITOBA AND ANOTHER SHORTWAVE OVER QUEBEC. A CUTOFF LOW IS
OVER THE LWR MISSISSIPPI VALLEY. INCREASING SW FLOW AHEAD OF THE
MANITOBA SHORTWAVE HAS SCOURED OUT LOW CLOUDS ACROSS MOST OF THE
FCST AREA WITH DOWNSLOPING NEAR LAKE SUPERIOR AIDING THE CLEARING
TREND. AS OF 2030Z...LAST OF THE LOW CLOUDS ARE DOWNWIND OF LAKE
MICHIGAN...E OF KESC-GRAND MARAIS LINE. APPROACHING COLD FRONT
ASSOCIATED WITH MANITOBA SHORTWAVE IS NOT ACCOMPANIED BY ANY PCPN S
OF THE INTERNATIONAL BORDER AS AIRMASS IS DRY PER 12Z SOUNDINGS.
&&
.SHORT TERM /TONIGHT AND TUE/...
SHORT TERM WILL BE GENERALLY QUIET AS OVERALL DRY AIRMASS LIMITS ANY
PCPN POTENTIAL DESPITE PASSAGE OF SHORTWAVE. COLD FRONT ASSOCIATED
WITH SHORTWAVE MOVING ACROSS ONTARIO TONIGHT WILL BRING A WIND SHIFT
AND USHER IN A PERIOD OF DECENT CAA (850MB TEMPS FALL FROM 0 TO 2C
THIS EVENING TO -6 TO -8C BY 12Z TUE). SHOULD BEGIN TO SEE AN
INCREASE IN LAKE EFFECT CLOUDS OVERNIGHT AS OVERWATER INSTABILITY
IMPROVES. OTHERWISE...NO PCPN IS EXPECTED AS AIRMASS IS DRY.
ON TUE...BRISK N WINDS AND MORE THAN ADEQUATE OVERWATER INSTABILITY
WILL LEAD TO QUITE A BIT OF STRATOCU OFF LAKE SUPERIOR. ALTHOUGH
850MB TEMPS ARE MARGINALLY COLD TO SUPPORT FLURRIES/-SHSN OFF THE
LAKE...TEMPS IN THE SHALLOW MOIST LAYER ARE JUST ABOVE -10C. IF
ANYTHING...THERE MIGHT BE SOME -FZDZ...BUT SUBCLOUD LAYER ON FCST
SOUNDINGS LOOKS TOO DRY TO SUPPORT THAT. THE LACK OF LOW CLOUDS WELL
UPSTREAM SUPPORTS MODEL FCST OF SOMEWHAT DRIER LOWER BOUNDARY LAYER.
IF THERE SOMEHOW IS A LITTLE PCPN TUE...IT WOULD PROBABLY BE OVER
NCNTRL UPPER MI (ERN BARAGA/MARQUETTE/WRN ALGER) DUE TO
PRECONDITIONING/STREAMLINE OFF LAKE NIPIGON INTO THAT AREA. IT WILL
BE A SEASONABLY CHILLY DAY WITH HIGHS IN THE UPPER 20S TO MID 30S.
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
TUESDAY NIGHT THROUGH WEDNESDAY EVENING...
WITH THE CONTINUED NORTHEASTWARD EJECTION OF
THE CUT OFF LOW OVER THE OHIO VALLEY AT 00Z WEDNESDAY TO THE LOWER
GREAT LAKES BY DAYBREAK WEDNESDAY...AND ACROSS QUEBEC THEREAFTER.
THE RESULT FOR THE UPPER GREAT LAKES WILL BE A 500MB RIDGE
OVERHEAD...AND A RIDGE OF HIGH PRESSURE EXTENDING ACROSS THE AREA
FROM TX. SENSIBLE WEATHER WISE...EXPECT DRY CONDITIONS WITH WARMING
ALOFT FROM A CWA AVERAGE -4 TO -1C AT 850MB DURING THE PERIOD.
THURSDAY MORNING THROUGH FRIDAY MORNING...
THE NEXT FEATURE OF INTEREST WILL BE SLIDING ACROSS EASTERN MT
WEDNESDAY MORNING...AND BETTER ORGANIZING FROM ND TO EASTERN CO BY
18Z WEDNESDAY. THE FEATURE WILL THEN WEAKEN AS IT SETS UP FROM UPPER
MI THROUGH TX BY 18Z THURSDAY. WITH THE ASSISTANCE OF SOME MID LEVEL
SUPPORT ON THE NORTHERN EDGE OF THIS FEATURE /500MB TROUGH EXTENDING
SW FROM THE NORTHERN PORTIONS OF HUDSON BAY/ LIGHT PRECIPITATION
WILL BE POSSIBLE...MAINLY BEHIND THE SFC LOW. NORTHERLY FLOW AND
850MB TEMPS OF -7 TO -9C BY 18Z THURSDAY SHOULD BRING ABOUT LIGHT
SNOW SHOWERS. INDICATIONS CONTINUE TO POINT AT 1 TO 3 INCHES OF SNOW
THURSDAY ACROSS THE KEWEENAW PENINSULA...WITH VALUES REMAINING BELOW
ADVISORY HEADLINE CRITERIA AT THIS TIME. COOLER NW FLOW WILL THEN
DOMINATE THURSDAY NIGHT WITH 850MB TEMPS BOTTOMING OUT AROUND -13C
BY 12Z FRIDAY...WHILE THE 500MB AXIS AND SFC FRONT EXIT TO OUR
EAST...LIMITING SIGNIFICANT SNOWFALL ACCUMULATIONS.
FRIDAY AFTERNOON AND EVENING...
WAA WILL QUICKLY TAKE HOLD FRIDAY AFTERNOON THROUGH THE EVENING
HOURS WITH 850MB TEMPS REBOUNDING TO AROUND -1 TO -4C DEPENDING ON
WHAT MODEL YOU BELIEVE...AND A WEAK RIDGE SLIDING ACROSS ALOFT.
EITHER WAY IT SHOULD BE DRY WITH SW WINDS...WITH THE LAST OF THE
LAKE EFFECT/LAKE ENHANCED PRECIP ENDING AT 12Z FRIDAY ON MAINLY
WESTERLY WINDS.
BEYOND FRIDAY EVENING THE FORECAST BEGINS TO BECOME A LITTLE LESS
PREDICTABLE. A 500MB TROUGH SET UP FROM N CENTRAL CANADA THROUGH MT
AT 18Z FRIDAY WILL ATTEMPT TO PUSH A SOUTHWESTERN U.S. CUT OFF LOW
INTO THE MAIN FLOW OVER THE WEEKEND...WITH THE ELONGATED TROUGH
SLIDING OVER THE UPPER GREAT LAKES SOMETIME BETWEEN SATURDAY MORNING
AND SUNDAY AFTERNOON...WITH AN ADDITIONAL WAVE ALMOST RIGHT BEHIND
THE PRIMARY WAVE FOR SUNDAY AFTERNOON OR MONDAY AFTERNOON.
YES...THERE IS NEARLY A 24 HOUR DIFFERENCE BETWEEN THE 28/00Z RUN OF
THE ECMWF AND THE 28/00Z AND 06Z RUNS OF THE GFS. THE 12Z RUNS OF
THE GFS AND ECMWF HAVE COME INTO A LITTLE BETTER AGREEMENT ONCE
AGAIN...AND WE WILL HAVE TO WAIT AND SEE IF THIS TREND CONTINUES.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
LOW CLOUDS/MVFR CIGS HAVE BEEN BREAKING UP UNDER STRENGTHENING SW
FLOW. LOW CLOUDS HAVE CLEARED KIWD/KCMX...AND KSAW SHOULD SEE LOW
CLOUDS SCATTER OUT IN THE NEXT HR OR TWO. VFR CONDITIONS WILL THEN
PREVAIL THRU THE AFTN HRS. A COLD FRONT WILL SHIFT ACROSS THE AREA
TONIGHT. INITIALLY...AIRMASS WILL BE TOO WARM FOR LAKE EFFECT
CLOUDS...BUT WILL NEED TO WATCH FOR A BRIEF PERIOD OF MVFR CIGS JUST
BEHIND FRONT THIS EVENING. SATELLITE IMAGERY/SFC OBS SHOW A NARROW
POST-FRONTAL BAND OF MVFR CIGS...BUT THERE IS UNCERTAINTY WHETHER
THE SRN END OF THE STRATOCU DECK WILL SLIP FAR ENOUGH S TO AFFECT
KCMX/KSAW. AS AIRMASS BECOMES COLDER AND OVERWATER INSTABILITY
INCREASES...EXPECT STRATOCU/MVFR CIGS TO DEVELOP OFF LAKE SUPERIOR
AND AFFECT KIWD/KCMX/KSAW TUE MORNING.
&&
.MARINE /FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE/...
TYPICAL CHANGEABLE LATE FALL PATTERN EXPECTED THIS WEEK. COLD FRONT
WILL PASS ACROSS THE AREA TONIGHT. MAY SEE A FEW GALE FORCE GUSTS
BTWN ISLE ROYALE AND THE KEWEENAW LATE THIS AFTN IN THE SW FLOW
AHEAD OF THE FRONT. BEHIND THE FRONT IN DECENT CAA REGIME...THERE
MAY BE SOME NORTHERLY GALE FORCE GUSTS FROM NCNTRL TO SCNTRL LAKE
SUPERIOR OVERNIGHT/EARLY TUE AS OVERWATER INSTABILITY INCREASES. AT
THIS TIME...IT APPEARS GALE GUSTS SHOULDN`T BE WIDESRPEAD OR
PERSISTENT ENOUGH TO WARRANT A GALE WARNING. WINDS WILL SLOWLY
DIMINISH FROM W TO E TUE AFTN/NIGHT AS HIGH PRES RIDGE MOVES CLOSER
TO THE AREA. LIGHTER WINDS UNDER 20KT WILL BE THE RULE WED
AFTN/NIGHT UNDER WEAK PRES GRADIENT ASSOCIATED SFC TROF SETTLING SE
INTO THE UPPER LAKES. N TO NW WINDS WILL INCREASE INTO THE 15-25KT
RANGE THU/THU NIGHT AS THE TROF SLIPS SE OF THE AREA. AFTER A BRIEF
PERIOD OF LIGHTER WINDS LATE THU NIGHT/FRI MORNING...WINDS WILL
AGAIN BE ON THE INCREASE LATER FRI INTO SAT AHEAD OF THE NEXT LOW
PRES TROF APPROACHING FROM THE NW. MAY SEE GALES IN THE SW FLOW
AHEAD OF THE TROF.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WARNING FROM 7 AM TO 7 PM EST TUESDAY FOR LMZ221-250.
&&
$$
SYNOPSIS...ROLFSON
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1246 PM EST MON NOV 28 2011
.SYNOPSIS.../ISSUED AT 1031 AM/
PATCHES OF LIGHT LAKE EFFECT SNOW WILL EVENTUALLY TAPER OFF BY
LATE TODAY. HIGH PRESSURE MAKES A BRIEF APPEARANCE TODAY. SKIES
WILL REMAIN MOSTLY CLOUDY. MORE PRECIPITATION IS IN STORE FOR
PARTS OF THE NORTHERN LOWER PENINSULA TUESDAY INTO TUESDAY
NIGHT...MAINLY FOR AREAS SOUTHEAST OF GAYLORD. EASTERN UPPER WILL
PROBABLY STAY DRY THROUGH THIS PERIOD.
LOCKER/HALBLAUB
&&
.SHORT TERM.../ISSUED AT 1031 AM/...THIS AFTERNOON
...MOSTLY CLOUDY AND CHILLY WITH CONTINUING POTENTIAL FOR PATCHES
OF LIGHT SNOW NEAR THE COASTS THRU AFTN...
UPPER-LEVEL FLOW IS HIGHLY AMPLIFIED OVER N AMERICA...BUT
PROGRESSIVE OVER CANADA AND THE NRN USA. SHRTWV RIDGING IS BUILDING
OVER THE GTLKS IN ADVANCE OF THE NEXT TROF CURRENTLY MOVING THRU
MANITOBA-MONTANA. THE SRN USA FLOW IS MORE BLOCKY AND THE TAIL END
OF AN ANTICYCLONIC WAVE-BREAKING EVENT HAS RESULTED IN A CLOSED LOW
OVER THE TN VALLEY IN THE LAST 24 HRS.
AT THE SFC...YESTERDAY`S COLD FRONT /THAT HAS ESTABLISHED MUCH MORE
SEASONABLE TEMPS/ WAS ALONG THE APPALACHIANS WITH A SFC LOW OVER NRN
GA. HIGH PRES EXTENDED FROM OK TO THE GTLKS. THE NEXT INACTIVE COLD
FRONT WAS MOVING INTO THE NRN PLAINS.
CLOUDS: FOG/REFLECTIVITY PRODUCT OVERLAID WITH 925 MB ANALYSIS SHOWS
THAT MVFR STRATUS IS ASSOCIATED WITH THE LOW-LEVEL THERMAL TROF/COLD
POOL. EROSION OF BACK EDGE IS OCCURRING WITH WAA. INTERESTING TO
NOTE THAT THIS EDGE HAS ONLY PROGRESSED FROM WRN MN BORDER TO THE MS
RIVER IN THE LAST 24 HRS.
INITIAL VIS CHANNEL IMAGERY SHOWS BREAKS AND THIN SPOTS. THESE AND
ANY OTHER BREAKS THAT DEVELOP WILL FILL BACK-IN WITH THERMAL TROF
OVERHEAD. SO MAINTAINED A M/CLOUDY FCST FOR THE REST OF THE DAY AND
INCREASED SKYCOVER AFTER 15Z. THE ERN U.P. COULD TURN P/CLOUDY LATE
BUT IT WILL PROBABLY OCCUR JUST BEFORE SUNSET.
INTERESTING CLOUD MICROPHYSICS. STRATUS IS YIELDING PATCHES OF FINE
SNOW GRAINS. THE COLDEST TEMP /AT THE BASE OF THE INVERSION/ IS -7C.
UNSURE HOW FAR TO EXTEND THIS THRU THE DAY. CONDITIONS APPEAR
FAVORABLE FOR IT TO CONTINUE AND 3KM HRRR IS THE ONLY MODEL SHOWING
IT. SO EXPANDED THE THREAT THRU 21Z...MAINLY FOR IMMEDIATE LAKESHORE
COUNTIES BUT THERE COULD BE FLURRY FURTHER INLAND.
TEMPS: THEY`RE REALLY GOING NOWHERE...HOLDING STEADY. THEY`RE NOT
FOLLOWING THE FCST TEMP CURVE DUE TO CLOUD COVER. SO 3-5F WERE
TRIMMED OFF AFTN HIGHS FROM 4 AM APX FCST.
HALBLAUB
&&
.LONG TERM.../ISSUED AT 445 AM/...TONIGHT AND BEYOND
TONIGHT...THE HIGH PRESSURE GOES VIRTUALLY NO WHERE...REMAINING
OVER NRN LOWER...WHILE THE LOW PRESSURE FROM TENNESSEE AND THE
COLD FRONT OUT TO OUR WEST BEGIN TO CONVERGE ON THE GREAT LAKES.
THE SW WIND PICKS UP A BIT ACROSS NW LOWER AND EASTERN UPPER WITH
ADDITIONAL 925MB WARMING...WHICH SHOULD EAT AWAY AT THE
STRATOCU. HOWEVER...INCREASING HIGH CLOUDS FROM BOTH FEATURES
WILL RESULT IN INCREASING CLOUDINESS FOR WHEREVER IT DOES START OF
ON THE CLEARER SIDE OF THINGS. MODEL CONSENSUS SUGGESTS THAT A
DEEP ATLANTIC MOISTURE FEED INTO THE NORTHWARD PROGRESSING LOW
PRESSURE WILL GET WRAPPED AROUND INTO A TROWEL WHICH LIFTS NORTH
OF THE OHIO RIVER VALLEY NEAR DTX BY DAYBREAK. MEANWHILE...NEAR
THE SAGINAW BAY REGION DEFORMATION ZONE AND FGEN ALOFT SNEAKS IN
OVER THE FAR SE CWA FOR SOME MODEL SUGGESTED LIGHT RAIN
DEVELOPMENT. HOWEVER...ANTECEDENT EXTREMELY DRY AIR MASS WILL BE
DIFFICULT TO MOISTEN...ESPECIALLY WHEN CONSIDERING STRENGTHENING
FGEN AND SHARP CUT OFF TO THE NRN EDGE OF THE RAIN SHIELD. MODEL
SOUNDINGS DO NOT SUPPORT ANY PRECIPITATION...AND LOWERED THE
CHANCE FOR SEEING PRECIP...BUT DID LEAVE A SMALL CHANCE RIGHT
NEAR THE SAG BAY. LOW TEMPS WILL BE IN THE LOW 30S.
TUESDAY THROUGH WEDNESDAY...LOW PRESSURE WILL LIFT THROUGH THE
EASTERN GREAT LAKES AND DEEPEN WHILE PARENT UPPER CUT OFF LOW
WILL TRY AND PHASE TO SOME DEGREE WITH NRN STREAM ENERGY. UPSTREAM
COLD FRONT DROPS IN ACROSS NRN MICHIGAN AND MESHES WITH THE LOW
PRESSURE RESULTING IN STRENGTHENING NORTHERLY WINDS AND DRY
ADVECTION OUT OF EASTERN UPPER. MEANWHILE THE DEFORMATION/FGEN AND
TROWAL LIFTS UP INTO NE LOWER. EXACTLY HOW FAR NORTH THE SHARP
CUTOFF TO THE NRN EDGE OF THE PRECIPITATION MAKES IT...IS STILL A
BIT UNCLEAR. THAT SAID...FEEL THAT THE NW HALF OF THE CWA IS
LIKELY TO SEE NO PRECIPITATION...WHILE A GOOD CHUNK OF NE LOWER IS
GONNA GET A LITTLE DAMP. MODEL SUGGESTIONS OF WARM WEDGE OF AIR
ALOFT (TROWAL) MOVING IN OVER SFC TEMPS LOWERING TO 32F OR LOWER
TUESDAY NIGHT IN PARTS OF THE PRECIP SHIELD ARE MOST LIKELY NOT
GONNA HAPPEN. TEMPERATURES OVER THIS AREA WILL LIKELY REMAIN AT OR
JUST ABOVE FREEZING...AND ANY CHANCE OF NEW NAM SOUNDINGS
SUGGESTING SOME FREEZING RAIN ARE SMALL. HAVE CONTINUED THE THEME
OF RAIN AND SNOW...BUT LOWERED THE POTENTIAL SNOW AMOUNTS DUE TO A
WARMER SCENARIO/HIGHER SNOW/WATER RATIOS. MAYBE AN INCH AROUND THE
SAGINAW BAY. DUE TO THE UNCERTAINTY AND MARGINAL THERMAL REGIMES
WILL CONTINUE TO MENTION THE POTENTIAL FOR ACCUMULATING SNOW IN
THE HWOAPX. THE WEATHER IMPROVES INTO WEDNESDAY AS THE LOW
PRESSURE WORKS ITS WAY OUT OF THE EASTERN GREAT LAKES...TAKING THE
DEEPER MOISTURE AND FORCING OUT OF NE LOWER. OUTSIDE OF NE
LOWER...THE REMAINDER OF THE CWA WILL LIKELY BE UNDER AT LEAST
HIGH LEVEL CLOUDS. SKIES WILL BE CLEAREST ACROSS FAR WESTERN
CHIP/MACK COUNTIES. HIGHS WILL BE IN THE UPPER 30S TO AROUND 40
DEGREES AGAIN.
THURSDAY ONWARD...ONE NORTHERN STREAM SHORTWAVE STILL EXPECTED
THURS-THURS NIGHT FOR POSSIBLE CHANCE AT SNOW...WHILE A BETTER
SHOT MAY DEVELOP OVER THE WEEKEND. NOT MANY CHANGES IN THIS TIME
PERIOD.
SMD
&&
.MARINE.../ISSUED AT 1131 AM/
HIGH PRES IS OVER THE LAKES TODAY...RESULTING IN LIGHT WINDS AND
LOW SEAS. HALBLAUB
THE MAIN MARINE ISSUE WILL BE A LOW PRESSURE SYSTEM LIFTING
THROUGH THE EASTERN GREAT LAKES TUESDAY THROUGH WEDNESDAY. A TIGHT
PRESSURE GRADIENT IS ANTICIPATED WITH DEFINITE SMALL CRAFT
ADVISORIES ACROSS ALL NEARSHORES. THE GALE POTENTIAL IS BECOMING
MORE CERTAIN FOR PORTIONS OF THE NEARSHORES OF LAKE MICHIGAN AND
HURON...MAINLY SURROUNDING NORTHERN LOWER MICHIGAN.
SMD
&&
.AVIATION.../ISSUED AT 1246 PM/...VALID FOR 18Z TAFS
...STRONG CROSS WINDS BEGIN TUE AT ALL TERMINALS EXCEPT ALPENA...
HIGH PRES IS OVERHEAD TODAY. COLD FROPA OCCURS TNGT WITH STRONG LOW
PRES APPROACHING THE GTLKS FROM THE S TUE-WED.
REST OF THIS AFTN: 2000-3000 FT MVFR CIGS WILL CONTINUE WITH LGT
WINDS. COULD SEE A FEW BINOVC. WITH MODEL GUIDANCE NOT HANDLING LOW
CLOUDS WELL...THIS FCST IS MAINLY PERSISTENCE. SO WE LOOK TO
ANYTHING THAT MIGHT CHANGE THE PRESENT SITUATION. ATTM IT DOES NOT
APPEAR ANYTHING WILL CHANGE UNTIL TNGT.
TNGT: COLD FROPA WILL OCCUR 05-06Z PLN TVC MBL AND 08-09Z APN. THIS
WILL ADVECT IN DRIER LOW-LEVEL AIR AND BELIEVE THIS WILL SCOUR OUT
MVFR CIGS. WINDS WILL BE LGT UNTIL FROPA THEN BECOME NNE 3-10 KTS.
LOSS/DIMINISHING OF LOW STRATUS WILL REVEAL VFR CIRRUS CIGS.
PERIOD OF VFR WILL BE PROBABLY BE SHORT-LIVED AT APN. NE WINDS WILL
RESULT IN MVFR LAKE CLOUDS MOVING INTO APN BEFORE SUNRISE.
TUE THRU 18Z: SIGNIFICANT CROSS WINDS WILL BE A PROBLEM AT MBL TVC
PLN. N-NE WINDS WILL INCREASE AND GUST UP TO 30 KTS WITH THE HIGHEST
PROBABILITY OF G30 OCCURRING AT MBL. ISOLATED HIGHER GUSTS ARE
POSSIBLE AFTER 18Z.
MVFR LAKE CLOUDS CONTINUE AT APN AND VFR THICKENING MID-HIGH LEVEL
CIGS. THERE COULD BE A FEW LAKE CLOUDS AT TVC AND MBL...BUT NOT
EXPECTED TO BECOME BKN.
HALBLAUB
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...GALE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY AFTERNOON FOR
LHZ347>349.
LM...GALE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY AFTERNOON FOR
LMZ323-342-344>346.
LS...NONE.
&&
$$
WFO APX
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1227 PM EST MON NOV 28 2011
UPDATED AVIATION DISCUSSION FOR THE 18Z TAFS
.SYNOPSIS /ISSUED AT 514 AM/...
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGING FROM
THE SW CONUS THROUGH THE UPPER MS VALLEY TO HUDSON BAY AND A CUTOFF
LOW OVER THE LOWER MS VALLEY. MAINLY ZONAL NRN STREAM FLOW
PREVAILED FROM THE EPAC THROUGH SRN CANADA AND THE NRN PLAINS. A
SHORTWAVE TROUGH EXTENDED FROM SRN SASK INTO NW MT WAS MOVING
STEADILY TO THE EAST. AT THE SFC...SRLY WINDS WERE INCREASING OVER
MN AND THE ERN DAKOTAS BTWN A TROUGH FROM MANITOBA TO THE WRN PLAINS
AND A RIDGE INTO THE WRN GREAT LAKES. IR 11-3.9 LOOP SHOWED THAT THE
BACK EDGE OF PERSISTENT LOW CLOUDS OVER UPPER MI...WI AND ERN MN WAS
ONLY MAKING SLOW OR LITTLE PROGRESS TO THE EAST. KINL/KMPX/KGRB
SOUNDINGS SHOWED MOIST LAYER TRAPPED BELOW A STRONG 900-850 MB
INVERSION. RADAR INDICATED THAT THE LIGHT LAKE EFFECT SNOW SHOWERS
OR FLURRIES OVER ERN LAKE SUPERIOR HAD DIMINISHED TO NO MORE THAN A
FEW FLURRIES FROM MUNISING EASTWARD.
&&
.DISCUSSION... ISSUED AT 514 AM EST
TODAY...NAM/RUC 925-900 MB RH PROGS SUGGEST THAT THE LOW CLOUDS
SHOULD DISSIPATE AND/OR DEPART TO THE EAST THIS MORNING AS LOW LEVEL
SW WINDS INCREASE. THIS WOULD LEAVE PARTLY TO MOSTLY SUNNY SKIES
THIS AFTERNOON AS MID/HIGH CLOUDS SUPPORTED BY WAA AHEAD OF THE
PLAINS TROUGH SPREAD INTO THE AREA. HOWEVER...SINCE THE MODELS HAVE
RECENTLY BEEN TOO EAGER TO REMOVE THE LOWER CLOUDS...EXPECT A DELAY
IN CLEARING MAY EXTEND INTO THE AFTERNOON. THIS SHOULD LIMIT MAX
TEMPS TO MAINLY THE MID 30S...WITH SOME UPPER 30S TO AROUND 40
READINGS AT LOCATIONS FAVORED BY SW DOWNSLOPE FLOW.
TONIGHT...THE SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WILL DRAG
A COLD FRONT/TROUGH THROUGH THE AREA. THE WEAK TO MODERATE QVECTOR
FORCING ACCOMPANYING THE TROUGH WILL REMAIN MAINLY NORTH OF THE CWA.
WITH LITTLE MOISTURE AVAILABLE...NO MEASURABLE PCPN IS EXPECTED.
KEPT TEMPS NEAR THE HIGHER END OF GUIDANCE AS CLOUDS WILL AGAIN KEEP
TEMPS FROM FALLING OFF TOO MUCH.
TUESDAY...STIFF NRLY WINDS WITH INFLUX OF LAKE MOISTURE AND
UPSLOPE FLOW WILL SUPPORT PERSISTENT LOWER CLOUDS OVER THE AREA.
ALTHOUGH THE SHALLOW LOWER CLOUD LAYER EXTENDING ONLY UP TO 900-850
TEMPS AROUND -6C MAY SUGGEST POTENTIAL FOR -FZDZ...A RELATIVELY DRY
SUB CLOUD LAYER WOULD NOT BE FAVORABLE.
TUE NIGHT INTO WED...WITH THE MID LEVEL AND SFC RIDGE BUILDING INTO
THE AREA...ALONG WITH DRY ADVECTION...CLEARING SHOULD TAKE OVER BY
LATE TUE AND LINGER INTO WED MORNING. SO...TEMPS NEAR CONSENSUS
GUIDANCE APPEARED REASONABLE WITH READINGS INTO THE UPPER TEENS
INLAND WEST AND MID 20S NEAR THE LAKES AND OVER THE ERN CWA. TEMPS
SHOULD REBOUND TO THE MID AND UPPER 30S WED.
WED NIGHT INTO THU...THE GFS/ECMWF/GEM SUGGEST THAT ANOTHER
SHORTWAVE AND FRONT MOVING THROUGH THE AREA ACCOMPANIED BY AT LEAST
MODERATE MID LEVEL FGEN WILL SUPPORT AN AREA OF LIGHT SNOW OVER THE
REGION. DIFFERENCES REMAIN WITH THE PLACEMENT/INTENSITY OF THE PCPN.
FOR NOW...ONLY CHANCE POPS WERE INCLUDED.
FRI...CAA IN THE WAKE OF THE FRONT DROPPING 850 MB TEMPS INTO THE
-12C TO -14C...PER GFS/ECMWF RANGE SHOULD GENERATE LES INTO EARLY
FRI FOR NW FLOW SNOWBELTS. ANY LES WOULD BE SHORTLIVED AS THE
PROGRESSIVE PATTERN WOULD LIKELY BRING WAA QUICKLY BACK INTO THE
AREA BY THE END OF THE WEEK.
INTO THE WEEKEND...
MODELS SHOW GENERAL TROUGHING PATTERN INTO THE CNTRL CONUS.
HOWEVER...SIGNIFICANT DIFFERENCES EMERGE REGARDING WHETHER THE DRIER
NRN STREAM WILL DOMINATE WITH MAINLY LES CHANCES (GFS) OR POSSIBLE
PHASING WITH SRN STREAM COULD BRING MORE SUBSTANTIAL MOISTURE/SNOW
INTO THE AREA (ECMWF). FOR NOW...THE FCST LEANS TOWARD THE GFS
SCENARIO WITH TEMPS FALLING INTO THE UPPER 20S AND LOWER 30S BY SUN
WITH LES CHANCES...TYPICAL FOR EARLY WINTER.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
LOW CLOUDS/MVFR CIGS HAVE BEEN BREAKING UP UNDER STRENGTHENING SW
FLOW. LOW CLOUDS HAVE CLEARED KIWD/KCMX...AND KSAW SHOULD SEE LOW
CLOUDS SCATTER OUT IN THE NEXT HR OR TWO. VFR CONDITIONS WILL THEN
PREVAIL THRU THE AFTN HRS. A COLD FRONT WILL SHIFT ACROSS THE AREA
TONIGHT. INITIALLY...AIRMASS WILL BE TOO WARM FOR LAKE EFFECT
CLOUDS...BUT WILL NEED TO WATCH FOR A BRIEF PERIOD OF MVFR CIGS JUST
BEHIND FRONT THIS EVENING. SATELLITE IMAGERY/SFC OBS SHOW A NARROW
POST-FRONTAL BAND OF MVFR CIGS...BUT THERE IS UNCERTAINTY WHETHER
THE SRN END OF THE STRATOCU DECK WILL SLIP FAR ENOUGH S TO AFFECT
KCMX/KSAW. AS AIRMASS BECOMES COLDER AND OVERWATER INSTABILITY
INCREASES...EXPECT STRATOCU/MVFR CIGS TO DEVELOP OFF LAKE SUPERIOR
AND AFFECT KIWD/KCMX/KSAW TUE MORNING.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
EXPECT INCREASNIG SW WINDS UP TO 30 KTS TODAY UNDER SHARPENING PRES
GRADIENT BETWEEN DEPARTING SFC HI OVER THE CENTRAL GREAT LAKES AND
AN APPROACHING COLD FRONT. THERE MAY EVEN BE A FEW GALE FORCE GUSTS
BETWEEN ISLE ROYALE AND THE KEWEENAW WHERE TERRAIN INFLUENCES WILL
ACCENTUATE THIS FLOW. AFTER THIS FRONT PASSES LAKE SUPERIOR
TONIGHT...THERE WILL BE WSHFT TO THE N. DEPENDING ON HOW QUICKLY A
LO PRES SYSTEM DEVELOPS IN THE OHIO VALLEY AND HOW FAR THIS
DISTURBANCE TRACKS TO THE W...MARGINAL GALES ARE POSSIBLE OVER THE
CENTRAL AND EASTERN PARTS OF THE LAKE AS THE PASSAGE OF COLDER AIR
OVER THE RELATIVELY WARM LAKE WATERS ENHANCES MIXING OF STRONGER
WINDS ALOFT TO THE SURFACE. THESE STRONGER WINDS WILL DIMINISH W-E
AND SHIFT MORE TO THE WNW TUE NIGHT THRU WED NIGHT AS HI PRES BUILDS
TOWARD THE UPPER MIDWEST. LOOK FOR ANOTHER WSHFT TO THE N-NW ON THU
FOLLOWING THE PASSAGE OF ANOTHER TROF ACROSS LAKE SUPERIOR. ONCE THE
TRAILING HI SHIFTS TO THE S ON FRI...A STRONGER SW FLOW WILL
REDEVELOP IN THIS CHANGEABLE WEATHER PATTERN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...NONE.
LAKE SUPERIOR...NONE.
LAKE MICHIGAN...NONE.
&&
$$
SYNOPSIS...JLB
DISCUSSION...JLB
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
109 PM EST MON NOV 28 2011
.SYNOPSIS...
A STALLED FRONTAL BOUNDARY OVER WESTERN NEW YORK AND PENNSYLVANIA
MAY TRIGGER SOME SHOWERS OVER THE FINGER LAKES AND MOHAWK VALLEY
INTO TUESDAY. LOW PRESSURE MOVING NORTHWARD FROM THE TENNESSEE
VALLEY WILL PUSH RAIN INTO THE REGION TUESDAY NIGHT AND WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 925 AM...MINOR TWEEKS TO CRNT FCST. CDFNT REMAINS
DRAPED ACRS THE BGM CWA WITH 3-HRLY PRES RISES OF 3-4 MB CNTRD
OVER NRN NY. FNT CONTINUE TO MAKE SLOW SWD PROGRESS...WITH ELM NOW
SHOWING A LGT NE WIND. THE RUC APPEARS TO HAVE THE BEST HANDLE ON
THE SITN...SUGGESTING THE FNT MAY CONTINUE TO SAG SLOWLY SWD THIS
AFTN INTO THE REMAINDER OF THE SRN TIER BEFORE LIFTING NWD OVRNGT. WILL
KEEP CHC POPS FOR -SHRA ALONG AND N OF THE FNT FOR THIS AFTN. ACRS
NE PA...SOME BREAKS OF SUNSHINE AND TEMPS ARND OR INTO THE L60S.
PREV BLO...
FNTL BNDRY REMAINS NEARLY STATIONARY OVER THE NW CORNER OF THE
FCST AREA AND WILL REMAIN THE FOCUS OF LGT SHWRS THRU THE DAY.
CRNTS AND RADAR SHOW ONLY VERY LGT RAIN IN THE AREA ATTM...AND DO
NOT XPCT THE INTENSITY TO CHG MUCH AT ALL DURING THE DAY...SO
DESPITE THE LACK OF MVMT...EXCESSIVE RAINFALL AMTS NOT XPCTD.
LATEST SYR TEMPS 62 SO A TRICKY TEMP FCST IN THE GRIDS AS A NON
DIURNAL TEMPS TREND IS XPCTD THIS MRNG AND THIS AFTN AS THE ACTUAL
SFC BNDRY DRFTS SOUTH AND BRINGS COOLER AIR TO THE NW ZONES. NAM12
TEMP FCST SEEMED CLOSEST TO CRNTS AND CAPTURED THE COOLING TREND
UP NORTH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
MODELS CONT TO BE IN GOOD AGREEMENT ON THE UPR LOW OVER THE ERN
US. THIS BRINGS A FAIRLY HIGH CONFIDENCE FCST DESPITE THE NRMLY
UNPREDICTABLE NATURE OF CUT OFF OR CLSD LOWS. AS LOW DEEPENS AND
LIFTS NWRD TNGT...OLD BNDRY OVER WRN NY IS FRCD BACK WWRD AND
BRIEF RDGG RETURNS TO THE FCST AREA. THIS SHD KEEP THE FCST AREA
DRY THRU TUE AHD OF THE UPR LOW.
LOW APRCHS TUE NGT AND INITIAL BAND OF RAIN MVES INTO THE AREA.
DEEP SLY FLOW WITH A SUBTROPICAL CONNECTION WILL BRING A PD OF
HEAVY RAIN...MOST LIKELY BETWEEN 00Z AND 06Z WED. GOOD NEWS IS
THAT THE SYSTEM IS PROGRESSIVE SO RAIN DURATION WILL BE SHORT AND
SHD LIMIT THE CNCRN FOR ANY FLOODING ISSUES. LGTR RAIN WILL CONT
LTR TUE NGT INTO WED AS THE UPR LOW LIFTS THRU WRN NY. COOLER AIR
WRAPPING ARND THE BASE OF THE LOW WILL BEGIN THE RETURN TO MORE
SEASONABLE TEMPS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
4 AM UPDATE...THE AREA OF LOW PRESSURE MENTIONED ABOVE WILL
CONTINUE TO MOVE INTO EASTERN QUEBEC WEDNESDAY NIGHT. ON THE
BACKSIDE OF THE LOW ENOUGH COOL AIR AND PRECIP MAY LINGER AROUND
FOR A BRIEF SHOT OF LIGHT SNOW ESPECIALLY IN NY STATE. STILL SOME
UNCERTAINTY WITH THIS SCENARIO WITH THE GFS MORE MILD THAN THE
EURO WHICH WOULD INDICATE MORE OF A MIX WITH RAIN. WE MAY SEE A
BRIEF WINDOW OF LAKE EFFECT LATER WEDNESDAY NIGHT ESPECIALLY IF
THE COLDER EURO IS CORRECT...BEFORE BUILDING HEIGHTS BRING US DRY
WEATHER THURSDAY.
ANOTHER BRIEF SHOT OF CHILLY AIR LATER FRIDAY AND FRIDAY NIGHT MAY
BRING US A PERIOD OF SCT. SNOW SHOWERS WITH LAKE SNOWS POSSIBLE
BEHIND IT. MOST OF THE UPCOMING WEEKEND LOOKS DRY BUT PLENTY OF
UNCERTAINTY EXISTS WITH THE EVOLUTION OF A COLD FRONT LATER SUNDAY
INTO EARLY NEXT WEEK. THE GFS IS THE FASTER SOLUTION BRINGING IN
PRECIP BY LATE SUNDAY WHILE ALLOWING FOR COLDER AIR TO MOVE IN AS
EARLY AS SUNDAY NIGHT. THE EURO HOLDS THE FRONT BACK...KEEPS THE
WEEKEND DRY...AND WOULD KEEP US ALL LIQUID THROUGH MONDAY. HPC
GUIDANCE LEANS TOWARD THE EURO AND GIVEN THAT THE GFS IS HAVING
RUN TO RUN CONSISTENCY ISSUES (18Z GFS SUPPORTS SLOWER
SOLUTION...0Z RUN DOES NOT)...MORE CONFIDENT WITH THE EURO. WITH
THAT IN MIND WILL KEEP THE WEEKEND DRY AND WITH 850S ABOVE 0C
THROUGH MONDAY...ANY PRECIP DURING THIS TIME WILL BE IN THE LIQUID
FORM.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
WEAK SURFACE COLD FRONT CURRENTLY DRAPED ACROSS THE SOUTHERN TIER
WITH BOUNDARY JUST NORTH OF KBGM. CIGS ALONG AND BEHIND FRONT MVFR/IFR.
THIS BOUNDARY WILL GRADUALLY LIFT BACK NORTH ACROSS CENTRAL NY
LATE THIS AFTERNOON THROUGH EARLY EVENING. AS THIS OCCURS A SOUTHEAST
FLOW WILL DEVELOP. IN GENERAL CIGS WILL GRADUALLY IMPROVE LATE
THIS AFTERNOON THROUGH EARLY EVENING THEN DETERIORATE AGAIN LATE
TONIGHT ACROSS THE SOUTHERN TERMINALS AS SOUTHEAST FLOW BRINGS LOW
LEVEL MOISTURE INTO REGION.
FOR KRME/KSYR, MVFR CIGS THROUGH MID MORNING TUESDAY WITH
POSSIBLE IFR CIGS AT KRME THROUGH 21Z. AFTER 14Z CIGS AROUND 4K
FT.
AT KITH...IFR CIGS THROUGH EARLY EVENING WITH IMPROVEMENT TO MVFR
THEN POSSIBLE IFR CIGS AGAIN BETWEEN 09Z-13Z, VFR AFTER 14Z.
KELM/KBGM...OCCASIONAL MVFR THROUGH LATE AFTERNOON THEN VFR WITH
LOWERING CIGS INTO THE MVFR CATEGORY AFTER 06Z WITH IFR POSSIBLE
BETWEEN 09Z-13Z. AFTER 14Z CIGS AROUND 4K FT.
KAVP...VFR UNTIL LATE TONIGHT THEN LOWERING INTO MVFR BY 06Z WITH
POSSIBLE DRIZZLE AND IFR CIGS BETWEEN 09Z-13Z. CIGS REMAIN MVFR ON TUESDAY.
LIGHT NORTHERLY WIND BECOMING LIGHT AND VARIABLE THEN SOUTHEAST
LATE TONIGHT AROUND 5 KNOTS INCREASING TO 12 KNOTS ON TUESDAY.
KAVP LIGHT AND VARIABLE WINDS THROUGH LATE TONIGHT.
OUTLOOK...
TUE NIGHT...MVFR/IFR IN RAIN.
WEDNESDAY...PATCHY MVFR IN SHOWERS.
WEDNESDAY NIGHT...PATCHY MVFR IN RAIN/SNOW SHOWERS ESPECIALLY KRME/KSYR.
THURSDAY/THURSDAY NIGHT...VFR.
FRIDAY/FRIDAY NIGHT...PATCHY MVFR IN POSSIBLE SCATTERED RAIN/SNOW
SHOWERS.
SATURDAY...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DGM
NEAR TERM...
SHORT TERM...DGM
LONG TERM...HEDEN
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1130 AM CST MON NOV 28 2011
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT
310 AM CST MON NOV 28 2011
THE MAIN STORIES IN THE SHORT TERM ARE WITH THE PESKY STRATUS
THAT IS CURRENTLY DRAPED OVER MUCH OF THE REGION ALONG WITH THE
CHANCES FOR A LIGHT ACCUMULATION OF SNOW ON THURSDAY.
CURRENTLY...A SURFACE RIDGE OF HIGH PRESSURE EXTENDS FROM THE
SOUTHERN PLAINS THROUGH SOUTHEAST MINNESOTA AND LAKE SUPERIOR. A
STUBBORN LOW LEVEL STRATUS DECK REMAINS IN PLACE ACROSS MUCH OF
THE REGION ALONG THE EASTERN PERIPHERY OF THIS RIDGE. THE WESTERN
EDGE OF THIS CLOUD SHIELD HAS STARTED TO DRIFT EASTWARD OVERNIGHT
ACROSS EASTERN MINNESOTA AND SHOULD COME THROUGH THE FORECAST
AREA FROM WEST TO EAST TODAY. THE AREA OF LEAST CONFIDENCE IN THE
CLEARING OCCURRING IS IN FAR NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN AS THE STRATUS HAS BEEN SLOW TO MOVE IN CENTRAL IOWA.
THE 28.00Z NAM AND GFS APPEAR TO HAVE INITIALIZED TOO LOW ON THE
RH UNDER THE 900MB INVERSION...BUT THE 28.05Z RUC SEEMS TO HAVE A
BETTER HANDLE ON THE LOW LEVEL MOISTURE. THUS...HAVE GONE WITH A
PESSIMISTIC BLEND OF THE RUC AND PURE IR SATELLITE EXTRAPOLATION
TO GET THE CLEARING TREND DOWN. THIS CLOUD COVER WILL HAVE AN
IMPACT ON TEMPERATURES TODAY WITH THE HIGHEST VALUES TO THE
NORTHWEST WHERE THE SUN WILL BE OUT LONGER.
AFTER A BRIEF CLEAR PERIOD GOING INTO THE EVENING...MID TO HIGH
LEVEL CLOUD COVER WILL BE ON THE INCREASE AS A MID LEVEL TROUGH
NEAR SASKATCHEWAN DROPS SOUTHEAST INTO THE REGION. AS THIS TROUGH
INTERACTS WITH A CUTOFF LOW IN THE SOUTHEASTERN US IT WILL LOSE
SOME OF ITS BETTER FORCING WITH PV ADVECTION SHOWING A RAPID
DECREASE. WHILE PRECIPITATION LOOKS UNLIKELY...THIS TROUGH WILL
BRING A COLD FRONT ALONG WITH IT THAT WILL TRACK THROUGH TONIGHT.
WITH A SURFACE LOW TRACKING TO THE NORTH THROUGH THE OHIO RIVER
VALLEY AND A RIDGE OF HIGH PRESSURE FOLLOWING THE COLD FRONT...THE
UPPER MISSISSIPPI RIVER VALLEY WILL BE STUCK IN BETWEEN THESE TWO
FEATURES WITH A TIGHTENING PRESSURE GRADIENT. AS A RESULT...WIND
GUSTS OF 20-30KT WILL BE POSSIBLE ON TUESDAY...PARTICULARLY ACROSS
NORTHEAST IOWA AND SOUTHWEST WISCONSIN WHERE THE GRADIENT WILL BE
THE TIGHTEST.
THIS RIDGE OF HIGH PRESSURE WILL GRADUALLY SLIDE EASTWARD INTO THE
REGION WEDNESDAY INTO EARLY THURSDAY AND PROVIDE FOR SOME FAIRLY
COOL TEMPERATURES WITH LOWS IN THE TEENS. THE NEXT FEATURE OF NOTE IS
WITH A MID LEVEL TROUGH THAT IS EXPECTED TO DROP INTO THE REGION
ON THURSDAY. OVER THE PAST FEW DAYS...THE MODELS HAVE BEEN PRETTY
LOW ON PRODUCING ANY QPF OUT OF THIS FEATURE. HOWEVER...THE LATEST
TREND IS TO BE MUCH STRONGER WITH THIS MID LEVEL FEATURE AND
THEY SHOW QUITE A BIT OF QG FORCING WITH TROUGH. TEMPERATURES
WOULD BE COLD ENOUGH TO SUPPORT ALL SNOW ALONG AND BEHIND THE COLD
FRONT WHERE THE PRECIPITATION IS EXPECTED TO FORM. THIS LOOKS TO
BE A FAIRLY QUICK HITTER WITH LESS THAN A 6 HOUR WINDOW OF SEEING
THE SNOWFALL...SO TOTALS SHOULD BE FAIRLY LIGHT IF THIS DOES TAKE
SHAPE WITH THE SNOW ENDING THURSDAY NIGHT AS THE FORCING DROPS TO
THE SOUTHEAST OF THE REGION.
.LONG TERM...FRIDAY THROUGH SUNDAY NIGHT
310 AM CST MON NOV 28 2011
AFTER A RIDGE OF HIGH PRESSURE MOVES THROUGH ON FRIDAY...THE FOCUS
WILL BE ON THE WEEKEND AND WHETHER PRECIPITATION WILL FILL IN FROM
THE SOUTHWEST AS THE 27.00Z AND 26.12Z ECMWF IS SUGGESTING. THE
27.00Z SHOWS THE MID LEVEL CUT OFF LOW OVER THE FOUR CORNERS
REGION GETTING PICKED UP INTO THE NEXT TROUGH THAT TRACKS THROUGH
THE NORTHERN PLAINS SATURDAY INTO SUNDAY. THE 27.00Z
GFS...HOWEVER...KEEPS THIS LOW OUT OVER THE DESERT AND BRINGS THE
NORTHERN STREAM TROUGH THROUGH A LITTLE LESS AMPLIFIED. WITH A
COLD FRONT STALLED OUT JUST TO THE SOUTHEAST...PRECIPITATION IS
EXPECTED TO DEVELOP IN THE VICINITY OF IT AS THIS WAVE GETS PICKED
UP. TEMPERATURES SHOULD BE COLD ENOUGH TO SUPPORT ALL SNOW...SO
THIS SYSTEM WILL HAVE TO BE MONITORED FOR TRENDS AS THE GFS WOULD
SUGGEST THAT CONDITIONS WOULD BE DRY UNTIL SUNDAY NIGHT WHEN A
SYSTEM DROPS OUT OF SOUTHWESTERN CANADA.
&&
.AVIATION...THIS AFTERNOON THROUGH TUESDAY
1130 AM CST MON NOV 28 2011
MVFR/IFR STRATUS CLOUDS REMAIN TRAPPED ACROSS THE FCST AREA...UNDER
A VERY STRONG SUBSIDENCE INVERSION NEAR 925MB. THE MOISTURE/CLOUDS
ARE SHALLOWER TODAY...MORE IN THE 1000-1500 FT DEPTH RANGE. VIS
IMAGERY DID SHOW SOME THINNING OF THE STRATUS OVER PARTS OF THE FCST
AREA LATE THIS MORNING...THUS TRENDED TAFS TOWARD BKN DECKS FOR MID/
LATE AFTERNOON HOURS. APPEARS THE AREA WILL HAVE TO WAIT FOR MORE OF
A WEST OR NORTHWEST PUSH FROM THE LOW LEVEL WINDS TO FINALLY GET THE
LOW CLOUDS OUT OF THE AREA VERY LATE THIS AFTERNOON OR EARLY THIS
EVENING. LOW LEVEL WINDS GRADUALLY BECOME MORE SOUTHWEST AND WEST
LATER THIS AFTERNOON/EVENING AS LOW PRESSURE MOVES ACROSS SOUTHERN
CAN AND A COLD FRONT APPROACHES FROM THE NORTHWEST. NORTHWEST AND
NORTH GRADIENT WINDS INCREASE OVER THE AREA TONIGHT...BEHIND THE
FRONT AND ON THE BACK SIDE OF A STRONG LOW MOVING THRU THE OH
VALLEY. CLOUDS WITH THE FRONT MAINLY HIGH LEVEL. ONCE FRONT PUSHES
SOUTH ACROSS THE TAF SITES AND TAKES THE LOW CLOUDS WITH IT...VFR
CONDITIONS EXPECTED FROM THE MID EVENING HOURS TONIGHT THRU TUE AND
WED AS DRY HIGH PRESSURE FROM THE NORTHERN PLAINS BUILDS INTO THE
UPPER MIDWEST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
310 AM CST MON NOV 28 2011
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...DAS