FXUS61 KLWX 011632
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1132 AM EST TUE DEC 1 2009
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA TODAY WILL PUSH OFF THE COAST
TONIGHT. LOW PRESSURE IN THE NORTHERN GULF OF MEXICO WILL APPROACH THE
MID ATLANTIC STATES WEDNESDAY...BEFORE MOVING THROUGH THE REGION
WEDNESDAY NIGHT. HIGH PRESSURE BUILDS IN FRIDAY. A COASTAL
DISTURBANCE DEVELOPS OFF THE CAROLINAS AND MOVES OUT TO SEA OVER
THE WEEKEND.
&&
.NEAR TERM /THIS AFTERNOON/...
SOME VERY PLSNT WX FOR THE 1ST DAY OF DEC. HIGH PRES SOLIDLY OVER
THE RGN. I'VE REDUCED CLDS FOR THE DAYLGT HRS. TEMPS LOOK ON TRACK
- TOPPING OUT IN LM50S.
&&
.SHORT TERM /TONIGHT/...
SURFACE HIGH PRESSURE MOVES OFFSHORE TONIGHT. SOME INCREASING CIRRUS
CLOUDS ARE POSSIBLE AS LOW PRESSURE MOVES INTO THE GULF STATES
OVERNIGHT. LOWS IN THE 30S XCPT A40 IN THE CITIES.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY INTO THURSDAY...DEVELOPING SOUTHERN STREAM LOW EJECTS
NORTH FROM THE WESTERN GULF IN THE MORNING...AS UPPER TROUGH DIGS
INTO THE GREAT PLAINS. 00Z EURO/GFS/CANADIAN MODELS FINALLY IN
DECENT AGREEMENT WITH 995 MB LOW MOVING ALONG WEST SIDE OF
APPALACHIANS. STRONG MOISTURE CONVEYOR BRINGS SWATH OF RAIN ACROSS
THE CWA FROM WEST TO EAST WEDNESDAY AFTERNOON THROUGH THE
OVERNIGHT. SOME INSTABILITY EXPECTED WITH ISO THUNDER IN FOR THE
OVERNIGHT HOURS...QPF GENERALLY UP TO AN INCH. STRONG SLY
WINDS...25 TO 30 MPH WITH POSSIBLE WIND ADVISORY WINDS FOR THE
RIDGES. MOISTURE/TEMPERATURE ADVECTION RESULT IN INCREASING
TEMPERATURES OVERNIGHT.
THURSDAY...WITH LOW TO OUR NORTH /UPSTATE NY/ BY SUNRISE...WLY
DOWNSLOPING FLOW BRINGS QUICK END TO PRECIP EAST OF THE ALLEGHENY
FRONT. UPSLOPE PRECIP CHANGES OVER TO SNOW THURSDAY AS COLD CANADIAN
AIR BUILDS IN. WARM MORNING NEAR 60F FOR DC AND LOW TO MID 60S FOR
SRN MARYLAND QUICKLY COOLS INTO THE LOWER 50S FOR MOST OF THE DAY AS
DRIER AIR BUILDS IN.
FRIDAY...UPSLOPE FLOW CONTINUES...SO ANY DECENT MOISTURE WOULD ALLOW
SNOW SHOWERS OUT WEST TO PERSIST /THOUGH A GENERAL DECREASE IN
COVERAGE AND INTENSITY OF SNOW SHOWERS IS EXPECTED DURING THE DAY.
COOL AIR IN PLACE...MID TO UPPER 40S FOR HIGHS /COLD ENOUGH FOR SNOW
ALL DAY FOR ALLEGHENY FRONT/.
SATURDAY...UPPER TROUGH FINALLY REACHES THE COAST...TRIGGERING
COASTAL LOW DEVELOPMENT INVOF CAPE HATTERAS. WITH
CYCLOGENESIS...BANDED PRECIP /CERTAINLY COLD ENOUGH FOR SNOW/ COULD
EXPAND INTO OUR CWA. TIMING AND POSITION UNCERTAINTY WITH THIS LOW
STILL FAIRLY HIGH...CARRIED SCHC FOR SNOW FOR THE BALT-DC METRO
AREAS AND WEST WITH CHC FOR RAIN/SNOW FOR SOUTHERN MARYLAND FOR
SATURDAY. TROUGH AXIS OVERHEAD MEANS COLDEST TEMPERATURES FOR THE
PERIOD...STRUGGLING TO REACH 40F FOR AREAS EAST OF THE BLUE RIDGE.
REST OF WEEKEND INTO NEXT WEEK...LOW WOULD DEVELOP AND PUSH OUT TO
SEA AS HIGH PRESSURE BUILDS BACK ACROSS THE AREA. TEMPS REMAIN
SLIGHTLY BELOW NORMAL THOUGH SLOWLY WARM WITH HEIGHT RISES EACH DAY.
&&
.AVIATION /THIS AFTERNOON THROUGH SATURDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT.
STRONG LOW MOVES UP WEST SIDE OF APPALACHIANS WED/WED NIGHT BRINGING
SWATH OF RAIN ACROSS THE TERMINALS WED EVENING/NIGHT. ISO THUNDER
POSSIBLE IN THE MIDNIGHT TO EARLY MORNING THURSDAY TIMEFRAME. STRONG
PRESSURE GRADIENT ACROSS THE AREA WEDNESDAY NIGHT AS LOW CENTER
PASSES TO THE WEST TO BRING STRONG /25 TO 35 KT OR HIGHER/ SLY LOW
LEVEL WINDS. UNCERTAINTY ABOUT HOW STRONG THE SURFACE GUSTS WILL
BE...BUT LOW LEVEL WIND SHEAR OF PARTICULAR CONCERN. WINDS SHIFT TO
THE WEST AND DIMINISH THURSDAY MORNING POST FROPA AS LOW CONTINUES
TO SPEED NORTH.
HIGH PRESSURE/VFR FOR FRIDAY. WILL CONTINUE TO WATCH FOR A COASTAL
DISTURBANCE AND POSSIBLE LIGHT SNOW ON SATURDAY.
&&
.MARINE...
WINDS BLO SCA THIS AFTN AND TNGT.
STRONG LOW MOVES UP WEST SIDE OF APPALACHIANS WED/WED NIGHT BRINGING
SWATH OF RAIN WITH ISO THUNDER POSSIBLE ACROSS THE WATERS WED
NIGHT. SLY WINDS INCREASE THROUGH WEDNESDAY...RAISED AN SCA FOR THE
AFTERNOON AND EVENING HOURS. AS LOW PASSES TO THE WEST WEDNESDAY
NIGHT...STRONG PRESSURE GRADIENT OVER THE WATERS WILL LIKELY RESULT
IN GALES.
GRADIENT SLACKENS AND WINDS SHIFT TO THE WEST ON THURSDAY AFTER
EARLY MORNING FROPA. SCA CALIBER WLY WINDS LIKELY THROUGH THURSDAY
AFTERNOON. WESTERLY FLOW 10 TO 15 KT CONTINUES FOR FRIDAY. WILL
CONTINUE TO MONITOR COASTAL LOW DEVELOPMENT OFF HATTERAS ON SATURDAY.
&&
.TIDES/COASTAL FLOODING...
STRONG SE WINDS ARE EXPECTED TO DEVELOP WEDNESDAY AND WEDNESDAY
NIGHT ACROSS THE MIDDLE ATLANTIC. THESE WINDS MAY ELEVATE WATER
LEVELS ACROSS THE WESTERN SHORE OF THE CHESAPEAKE BAY AND TIDAL
POTOMAC.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM WEDNESDAY TO MIDNIGHT EST
WEDNESDAY NIGHT FOR ANZ530>543.
&&
$$
UPDATE...WOODY!
PRVS...NWL/BAJ
