FXUS61 KLWX 120231
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
931 PM EST SAT FEB 11 2012

.SYNOPSIS...
AN UPPER LEVEL DISTIRBANCE WILL PIVOT ACROSS THE AREA OVERNIGHT. HIGH
PRESSURE WILL BUILD ACROSS THE REGION THROUGH EARLY NEXT WEEK. AN
UPPER LEVEL DISTURBANCE MAY BRING PRECIPITATION TO THE REGION BY
MID WEEK...WITH ANOTHER COLD FRONT TO FOLLOW BY THE END OF THE
WEEK.

.NEAR TERM /THROUGH SUNDAY/...
SNSQ CLEARED THE AREA ERLR TAFTN...AND THE BLUSTERY COLD NW
WNDS BHD IT AFFECTING CWFA ATTM. NMRS GUSTS IN THE 35-40 KT RNG.
BUFKIT SNDGS REFLECT POTL OF 40-50 KT GUSTS ACRS MUCH OF AREA. LWX
RAOB BACKS THIS UP...W/ AN INVSN AT 4K FT...AND WNDS 43 KT AT THE
TOP OF THAT LYR. WND ADVY IN PLACE ACRS MOST OF CWFA TNGT...WHICH
SEEMS LIKE A GOOD BET.

18Z GDNC...SPCLY NAM...AS WELL AS LTST SREFS SUGGEST THAT SHSN IN
CENTRL PA...ASSOCD W/ S/WV W/IN H5 TROF AXIS...YET TO PIVOT ACRS
NERN CWFA TNGT. LTST WRF/HRRR RUNS CONCUR...ALTHO IT STARTS TO
ERODE CVRG INVOF DC. MORE IMPORTANTLY...RDR TRENDS VERIFYING THESE
MDL RUNS...AND HV GRND TRUTH FM A SPOTTER IN NRN CARROLL CNTY THAT
FRESH SNW HAS COVERED THE GRND. BASED ON AVBL S/WV ENERGY...DEPTH
OF TROF AXIS...AND STRONG CAA/NW FLOW...AM NOT PREPARED TO DOUBT
SHSN POTL TIL TROF AXIS ITSELF PIVOTS E OF CWFA. HV THEREFORE UPPED
POPS W/IN ITS PATH. AM KEEPING LKLY POPS NE OF A HGR-DCA-NHK LINE.
ACCUMS WUD BE SPOTTY...LESS THAN A HALF INCH.

OUT ON THE WESTERN SLOPES...UPSLOPE SNOW WILL CONTINUE ALL NIGHT AND 
INTO SUNDAY. HAVE RECEIVED REPORTS OF UP TO 7 INCHES ALREADY AT
BAYW2...SO MEETING THE WARNING THRESHOLD NOT A CONCERN. LEFT THE
WARNING IN PLACE AS IS.

ASIDE FROM THE UPSLOPE SNOW...THE FORECAST THROUGH SUNDAY CAN BE 
SUMMED UP IN ONE PHRASE...BRRR. LOWS TONIGHT WILL FALL TO AROUND 20 
IN MOST AREAS /CLOSER TO 10 OUT WEST/. HIGHS ON SUNDAY WILL STRUGGLE 
TO REACH FREEZING...AND WILL NOT MAKE FREEZING IN THE HIGHLANDS/BLUE 
RIDGE MTNS. WIND CHILLS WILL BE IN THE SINGLE DIGITS OVERNIGHT
IN MANY AREAS...AND BELOW ZERO IN THE POTOMAC HIGHLANDS. WIND
CHILLS TOMORROW...DESPITE A LITTLE SLACKENING OF THE WIND SPEEDS...
WILL STILL BE AROUND 20 ALL DAY.

HV TWEAKED TEMPS AND THUS WIND CHILLS BASED ON LAMP/18Z MAV/LTST
SREF. AREA OF GOING WIND CHILL ADVY STILL SEEMS TO FIT...AND WL
NOT EXPAND. THAT SAID...SOME OF THE RDG TOPS IN THE PTMC
HIGHLANDS/BLUE RIDGE WL BE AWFULLY CHILLY.

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
HIGH PRESSURE BUILDS IN SUNDAY NIGHT INTO MONDAY ACROSS THE CWFA. AN 
UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA MONDAY NIGHT
POSSIBLY BRINING SOME LIGHT PRECIP TO THE CWFA.

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AN ASSOCIATED COASTAL LOW PRESSURE SYSTEM WILL MOVE OFF THE COAST
OF THE CAROLINAS EARLY WEDNESDAY. UPSLOPE SNOW SHOWERS WILL LINGER
ACROSS THE WESTERN FACING SLOPES THROUGH WEDNESDAY EVENING.

HIGH PRESSURE RETURNS FOR WEDNESDAY NIGHT AND THURSDAY. HIGH CENTER 
WILL MOVE OFFSHORE THURSDAY AFTERNOON AS A COLD FRONT MOVES INTO THE 
OHIO VALLEY. THE FRONT IS EXPECTED TO IMPACT THE CWFA ON FRIDAY.

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
WIND IS THE BIG STORY THROUGH THE PERIOD...NWLY WINDS UP TO 25
KTS WITH GUSTS UP TO 40 KTS EXPECTED TONIGHT...AND STILL 20G30 KTS
DURING THE DAY ON SUNDAY. THERE WL BE ONE LAST S/WV APPROACHING
TERMINALS...SPCLY BALT AREA...OVNGT. SUSPECT TEHRE WL BE SCT SHSN
IN ITS VCNTY. DONT HV SUFFICIENT CONFIDENCE IN FLGT RESTRICTIONS
TO INCL IN TAFS...BUT ITS CERTAINLY A PSBLTY. WHATEVER DOES COME
WL BE BRIEF IN NATURE.

GUSTY NW WINDS WILL LINGER INTO SUNDAY NIGHT...BUT GRADIENT SHOULD 
RELAX AS HIGH PRESSURE BUILDS IN. GUSTS AROUND 25 KT WILL BE 
POSSIBLE THROUGH THE EVENING. 

SUB VFR CONDITIONS ARE POSSIBLE MONDAY NIGHT INTO TUESDAY AS AN 
UPPER LEVEL DISTURBANCE MOVES ACROSS THE MID ATLANTIC AND A COASTAL 
LOW MOVES OFF THE SE COAST. 

SUB VFR CONDITIONS ARE POSSIBLE AGAIN BY THE END OF THE WEEK AS A 
COLD FRONT MOVES THROUGH THE AREA.

.MARINE...
GALE WARNING IN EFFECT TONIGHT ALL AREAS. HV EXPANDED GLW TO INCL
ENTIRE MARINE AREA SUN AS WELL. NWLY WINDS UP TO 30 KTS WITH
GUSTS UP TO 45 KTS OVER THE WATERS TONIGHT...AND STILL 20G35 KTS
ON SUNDAY. WINDS SHOULD LESSEN FROM WEST TO EAST IN THE AFTN.

SMALL CRAFT CONDITIONS ARE LIKELY SUNDAY NIGHT ACROSS THE WATERS. 
HAVE OPTED TO HOLD OFF ISSUING THE HEADLINE IN CASE THE GALE WARNING 
LINGERS INTO SOME OF THE THIRD PERIOD. 

SMALL CRAFT CONDITIONS ARE POSSIBLE OVERNIGHT THURSDAY AND INTO 
FRIDAY AS A COLD FRONT APPROACHES THE REGION.

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...WIND ADVISORY UNTIL 7 AM EST SUNDAY FOR DCZ001.
MD...WIND CHILL ADVISORY UNTIL 10 AM EST SUNDAY FOR MDZ501.
     WIND ADVISORY UNTIL 7 AM EST SUNDAY FOR MDZ003007-009011-013-
     014-016018-501-502.
     WINTER STORM WARNING UNTIL 7 PM EST SUNDAY FOR MDZ501.
VA...WIND CHILL ADVISORY UNTIL 10 AM EST SUNDAY FOR VAZ503-504.
     WIND ADVISORY UNTIL 7 AM EST SUNDAY FOR VAZ025031-036040-042-
     051054-501504.
     WINTER STORM WARNING UNTIL 7 PM EST SUNDAY FOR VAZ503.
WV...WIND CHILL ADVISORY UNTIL 10 AM EST SUNDAY FOR WVZ501-503-505-
     506.
     WIND ADVISORY UNTIL 7 AM EST SUNDAY FOR WVZ050053-055-501506.
     WINTER STORM WARNING UNTIL 7 PM EST SUNDAY FOR WVZ501-503-505.
MARINE...GALE WARNING UNTIL 7 PM EST SUNDAY FOR ANZ530543.

SYNOPSIS...HTS/LISTEMAA
NEAR TERM...HTS/JE
SHORT TERM...LISTEMAA
LONG TERM...LISTEMAA
AVIATION...HTS/JE/LISTEMAA
MARINE...HTS/JE/LISTEMAA