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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 050335
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
1035 PM EST WED DEC 4 2013

.SYNOPSIS...
HIGH PRESSURE WILL LINGER OFF THE MID ATLANTIC COAST THROUGH
THURSDAY. MEANWHILE...A WARM FRONT LIFTS NORTH THROUGH THE REGION
TONIGHT. A SLOW MOVING COLD FRONT IS EXPECTED TO MOVE INTO THE
AREA BY MIDDAY FRIDAY...FOLLOWED BY A PERIOD OF UNSETTLED WEATHER
THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
-- Changed Discussion --
LATEST SFC ANALYSIS DEPICTS WEAK WARM FRONT OVER THE REGION WITH
A STRONGER WARM FRONT OVER NEW ENGLAND. WARM/MOIST LOW LEVEL SW
FLOW (BELOW AN INVERSION AROUND 800MB PER LATEST KWAL SOUNDING)
WILL CONTINUE TO SPREAD LOW LEVEL CLOUDS/STRATUS INTO THE REGION.
AREAS OF FOG...LOCALLY DENSE AT TIMES...WILL CONTINUE THRU LATE
TONIGHT INTO THURS MORNING. PRECIP SHOWING UP ON RADAR OFF THE MD
ERN SHORE WILL REMAIN OFFSHORE...BUT HAVE INCLUDED A SLIGHT CHANCE
FOR LIGHT RAIN/DRIZZLE ALONG THE IMMEDIATE COAST. NO RAINFALL
ACCUMULATION IS EXPECTED. REST OF THE LOCAL AREA WILL REMAIN DRY.
LITTLE CHANGE IN TEMPS EXPECTED TONIGHT AS WAA CONTINUES. LOWS
WILL LIKELY ONLY DROP A FEW MORE DEGS TONIGHT INTO THE LOW-MID
50S...10-15 DEGS ABOVE NORMAL.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY THROUGH FRIDAY NIGHT...
A COLD FRONT CROSSES THE OH VALLEY ON THURS AND GETS HUNG UP ALONG
THE SPINE OF THE APPALACHIANS THURS NIGHT INTO FRI MORNING. THIS IS
DUE TO A BLOCKING PATTERN DEVELOPING...WHERE A STRONG ARCTIC HIGH
IS DIGGING INTO THE NCTRL U.S. AND ANOTHER HIGH IN THE WRN
ATLANTIC IS PREVENTING THE COLD FRONT FROM PROGRESSING EWD.
BECAUSE THE PROGRESSION OF THE FRONT REMAINS SLOW ON THURS...HAVE
CONTINUED WITH A DRY FORECAST DURING THE DAY. HAVE MAINTAINED A
SCHC/CHC FOR PRECIP ALONG A LINE NORTH OF GENERALLY FARMVILLE-
RICHMOND-SALISBURY FOR LATE THURS NIGHT BUT SUSPECT THAT THIS MAY
NOT HAPPEN UNTIL CLOSER TO FRI MORNING. S-SW WINDS WILL HELP
BRING EVEN MILDER AIR INTO THE AREA...RESULTING IN HIGH TEMPERATURES
IN THE UPPER 60S TO AROUND 70 NORTH...AND LOW/MID 70S SOUTH...DESPITE
MOSTLY CLOUDY SKIES.

AS THE COLD ARCTIC AIRMASS FINALLY INTRUDES ON THE WARMER AIR TO
ITS SOUTH...THE FRONT WILL FINALLY START TO PUSH ACROSS THE AREA
FROM THE NORTHWEST BY FRI AFTN. SHARP TEMPERATURE AND PRESSURE
CONTRASTS BETWEEN THE WARMER AIRMASS OVER THE REGION VERSUS THE
COLD ARCTIC AIRMASS TO THE NORTHWEST WILL CAUSE SW WINDS TO BECOME
BREEZY WITH GUSTS UP TO 25 MPH DURING THE AFTN SOUTH OF THE COLD
FRONT. CONTINUED WAA ADVECTION SOUTH OF THE FRONT AND FAVORABLE MIXING
WILL ONCE AGAIN HELP TO BOOST HIGH TEMPS WELL ABOVE NORMAL ON
FRI...ESPECIALLY OVER SERN AREAS WHERE TEMPS SHOULD REACH THE MID-
UPPER 70S. FOR NW AREAS...TEMPS MAY ONLY BE IN THE LOW-MID 60S DUE
TO WHERE LOW CLOUDS AND PRECIP OCCUR. THE COLD FRONT CROSSES THE
REST OF THE FA FRI NIGHT AND MOVES JUST OFF THE COAST BY SAT
MORNING. PRECIPITATION IS EXPECTED TO BECOME MORE WIDESPREAD AND
STEADY OVERNIGHT FRI. LOW TEMPS FRIDAY NIGHT WILL BE TRICKY
DEPENDING ON HOW FAST THE POST-FRONTAL ARCTIC AIR CAN MOVE INTO
THE REGION AND WHEN WINDS TURN TO THE NORTHWEST/NORTH. AM
CURRENTLY ANTICIPATING A CONTRAST WITH LOWS IN THE UPPER 30S/LOWER
40S NW TO LOWER 50S FAR SE. AS FAR AS POPS ARE CONCERNED ON
FRIDAY...WILL CARRY LIKELY POPS 55-65% ACROSS FAR NORTHERN
AREAS...WITH LIKELY/CATEGORICAL POPS (70-80%) SPREADING SOUTH ACROSS
MUCH OF THE AREA FRIDAY NIGHT.

ON SATURDAY...
THE AFOREMENTIONED COLD FRONT STALLS OUT ACROSS THE SERN U.S. AS
ARCTIC HIGH PRESSURE EXPANDS EASTWARD FROM THE OHIO VALLEY INTO
THE NORTHEAST. N-NE SFC WINDS WILL CONTINUE TO FUNNEL COLDER AIR
INTO THE MID-ATLANTIC REGION THROUGH THE DAY WITH HIGHS DURING THE
DAY EITHER HOLDING STEADY OR ONLY RISING A COUPLE OF DEGREES FROM
THEIR MORNING LOWS. HIGHS AROUND 40 NW TO THE LOW/MID 50S SE. THE
QUESTION THAT STILL REMAINS IS JUST HOW MUCH PRECIP LINGERS ACROSS
THE LOCAL AREA ON SATURDAY. ATTM...THE ECMWF AND GFS MODELS STILL
FAVOR LIGHT RAIN LINGERING ALONG AND SOUTH OF A AVC-RIC-SBY LINE
THROUGH THE DAY. THE NAM/SREF DRIVES THE SFC COLD FRONT A LITTLE
FARTHER SOUTH WHICH SUPPORTS LESS PCPN ON SATURDAY...ESPECIALLY
AFTER NOON. TEND TO FAVOR THE PCPN GETTING HUNG UP AND BEING
SLOWER TO EXIT GIVEN THE POSITION/STRENGTH OF THE WRN ATLANTIC
RIDGE. THEREFORE...WILL KEEP CHC POPS ACROSS THE SERN HALF OF THE
FA THROUGH THE DAY.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
RATHER CHALLENGING FORECAST SATURDAY NIGHT AND SUNDAY AS BOTH THE
12Z GFS AND ECMWF ARE A BIT COLDER AT THE SFC DUE TO THE APPARENT
RIDGE BEING A BIT SLOWER TO MOVE OUT OF EASTERN NY. THIS WILL BE
CRITICAL AS TO WHERE SFC TEMPS FALL TO OR STAY BELOW 32 LEADING TO A
FZ RAIN VERSUS A COLD RAIN SCENARIO AS THE NEXT IN A SERIES OF S/W`S
RIDES NE WITH OVERRUNNING MOISTURE. LEANED TOWARD THE ECMWF SOLUTION
AS IT SEEMS TO HANDLE THE COLD WEDGE BETTER THAN THE GFS. THE GFS
HAS THE STRONGEST RIDGING EAST OF THE PIEDMONT WHILE THE EURO HAS
THE STRONGEST RIDGING ALONG AND JUST EAST OF THE MTS (WHICH IS KEY
TO HOLDING THE COLDER AIR IN LONGER). IN ADDITION...BUFKIT SOUNDINGS
SHOWS THE POTENTIAL FOR SEVERAL HOURS OF ICE (ALONG AND NW OF A
FVX-RIC-XSA LINE). SO WITH THIS IN MIND HAVE COME FURTHER SOUTH &
EAST WITH THE FZ RAIN LATE SATURDAY NIGHT...HAVE ALSO ADDED A FEW
HOURS OF SLEET AT THE ONSET MAINLY NW OF RIC GIVING THE INITIAL DRY
AIR. LOWS 30 NW TO 40 SE.

SUNDAY WILL HAVE ITS CHALLENGES AS THE COLD AIR GETS LOCKED IN
ACROSS THE PIEDMONT WITH STEADY OR SLOWLY RISING TEMPS TO JUST ABOVE
FREEZING IN THE AFTERNOON WHILE E-SE WINDS BRINGS MILDER AIR IN FROM
THE OCEAN WITH COASTAL TEMPS RISING WELL INTO THE 50S...POSSIBLY
NEAR 60. HAVE EXTENDED THE FZ RAIN INTO THE EARLY AFTERNOON ACROSS
LOUISA / FLUVANNA / WESTERN GOOCHLAND / CUMBERLAND COUNTYS WHERE THE
BEST CHCS FOR ACCUMULATING ICE WILL BE. OTW...LIKELY POPS FOR RAIN
INTO SUNDAY NIGHT WITH STEADY OR SLOWLY RISING TEMPS SUNDAY NIGHT.

DRYER AND COOLER CONDITIONS RETURN BY MID WEEK BEHIND A COLD FRONTAL
PASSAGE TUE. HIGHS TUE IN THE 40S/50S (FALLING TEMPS IN THE AFTERNOON).
LOWS TUE NIGHT IN THE 20S. COLD WED WITH HIGHS IN THE M30S-L40S.

&&

.AVIATION /04Z THURSDAY THROUGH MONDAY/...
AS OF 00Z...SFC WARM FRONT HAS LIFTED NORTH OF THE AREA. SLOLY
RISING TEMPS/DEWPTS INTO SRN/CNTRL VA WILL CREATE IFR/LIFR
CONDITIONS AT ALL SITES. WARMER SSW FLO WILL INCRS TO 10-15 KT
OR SO AND SHOULD SCATTER OUT THE LOW CLOUDS THU.

A COLD FRONT WILL BE SLOW TO PROGRESS INTO THE AREA FRI/FRI
NIGHT...HIGHEST CHANCES FOR SIGNIFICANT REDUCTIONS IN CIGS/VSBYS
LOOKS TO ARRIVE LATER FRI NIGHT THROUGH SAT/SUN. GENLY APPEARS TO
BE A RAIN EVENT FOR KORF/KPHF/KECG/KSBY...WITH SOME POTENTIAL FOR
MIXED PRECIP AT KRIC 2ND PART OF THE WKND.

&&

.MARINE...
NO HEADLINES IN SHORT TERM AS A LIGHT SOUTH FLOW FOLLOWS A WARM
FRONT AS IT LIFT NORTH OF THE AREA. FLOW BECOMES SW THU BUT EXPECT
WINDS OVER THE LAND TO BE A BIT HIGHER THAN OVER WATER. PRS GRADIENT
INCREASES THU NIGHT/FRI AHEAD OF A SLOW MOVING COLD FRONT. MIXING
WILL BE LIMITED..SO NO SCA EXPECTED DUE TO WINDS. WNA CONTINUES TO
ADVERTISE MARGINAL SCA CONDITIONS (5FT SEAS) OVER THE NORTHERN
COASTAL WATERS.

MODELS CONTINUE TO PROG POTENT COLD FRONTAL PASSAGE EARLY SAT
MORNING. SCA CONDITIONS APPEAR LIKELY FOR ALL ZONES BY SAT MORNING
AS STRONG HIGH PRESSURE BUILDS TO THE NORTH OF THE AREA AND MUCH
COLDER AIR ALOFT BEGINS TO MIX DOWN OVER THE WATERS. BOUNDARY STALLS
TO THE SOUTH AS STRONG HIGH PRESSURE BUILDS FROM THE GREAT LAKES TO
NEW ENGLAND ON SUNDAY...WITH SCA CONDITIONS STILL POSSIBLE.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...JDM
NEAR TERM...SAM
SHORT TERM...BMD/JDM
LONG TERM...MPR
AVIATION...ALB/DAP
MARINE...MPR