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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 060957
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
457 AM EST THU MAR 6 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS NORTH OF THE REGION TODAY. LOW PRESSURE OVER
THE DEEP SOUTH WILL MOVE NORTHEAST AND OFF THE MID ATLANTIC COAST
THURSDAY NIGHT AND FRIDAY. HIGH PRESSURE BUILDS OVER THE AREA
SATURDAY. A COLD FRONT CROSSES THE AREA SUNDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
LATEST WATER VAPOR SAT ANALYSIS SHOWING NORTHERN STREAM SHORTWAVE
PULLING EAST OFF THE EASTERN NEW ENGLAND COAST THIS MORNING.
MEANWHILE...SOUTHERN STREAM ENERGY CONTINUES TO DROP
EAST/SOUTHEAST TOWARDS THE GULF COAST. AT THE SURFACE, COLD 1040+MB
SFC HIGH PRESSURE CURRENTLY DROPPING SOUTH FROM THE ST LAWRENCE
VALLEY TOWARDS THE NORTHEAST THIS MORNING, WITH RESULTANT E-NE
FLOW BRINGING SCT STRATUS ALONG THE IMMEDIATE COASTAL ZONES.

UPPER TROUGH OVER THE GULF COAST WILL AMPLIFY AS IT AMBLES EAST
ACROSS THE DEEP SOUTH TODAY. GOOD AGREEMENT AMONGST MODEL GUIDANCE
INDICATING UPPER LOW CLOSING OFF LATER THIS MORNING, SPAWNING
SFC CYCLOGENESIS ACROSS THE EASTERN GULF COAST AREA BY MIDDAY.
COULD HAVE SOME PATCHY DZ ACROSS SE VA/NE NC ZONES AS MOISTURE
BEGINS TO STREAM NORTH FROM THIS SYSTEM. HOWEVER, FORECAST
SOUNDINGS INDICATES DRY SOUNDING ABOVE H9 SO WILL GO WITH A DRY
FORECAST FOR THE DAY DESPITE CONSIDERABLE CLOUDINESS THROUGH THE
DAY ON E-NE WIND. HIGHS GENERALLY IN THE 30S TO NEAR 40
NORTH...LOWER 40S SOUTH.

TONIGHT...CONTINUED TO USE AN ECMWF WEIGHTED ECMWF/GFS BLEND FOR
SYNOPTIC FEATURES. SFC LOW PROGGED TO BE NEAR SAVANNAH, GA (JUST
OFF FL/GA COAST) BY 00Z FRI, WITH SHRAS DEVELOPING ACROSS
DEVELOPING COASTAL TROUGH ALONG THE CAROLINA COAST TONIGHT. THIS
LOW THEN TAKES ON A MILLER-A TYPE TRACK AS IT SLIDES NE ALONG THE
CAROLINA COAST THROUGH LATE TONIGHT, EVENTUALLY SLIDING NE ACROSS
THE VA CAPES FRIDAY. PREDOMINATE P-TYPE WILL BE IN THE FORM OF
RAIN...HOWEVER PCPN TYPE ISSUES OCCUR LATE TONIGHT AND EARLY FRI
AS THE MOISTURE OVERSPREADS THE AREA. WITH TEMPS PROGGED TO FALL
TO NEAR/JUST BELOW FREEZING INLAND, A PERIOD OF LIGHT WINTRY
PRECIPITATION IS POSSIBLE LATE TONIGHT/ERY FRIDAY MORNING ACROSS
NW HALF OF THE AREA. GIVEN LL CAD AND PROGGED THICKNESSES...EXPECT
PCPN ACROSS PIEDMONT ZONES TO START OUT AS A RAIN/SLEET MIX (SOME
LIGHT SNOW TO START NORTH-NORTHWEST OF THE MIDLOTHIAN TURNPIKE IN
RIC METRO) BEFORE GOING OVER TO A PD OF LGHT SLEET/FZ RAIN AFTER
6-8Z/FRIDAY THRU ABT 15Z FRI. GIVEN LIGHT QPF ON THE ORDER OF A
TENTH OF AN INCH OR SO, NO SIGNIFICANT ICING IS EXPECTED. HOWEVER,
GIVEN THE RUSH HOUR TIMING, EVEN A FEW HUNDREDTHS OF FZ RAIN COULD
PROVE HAZARDOUS FRI MORNING (GRIDS WILL HAVE .01-.02 ICE
ACCUM...AND A VERY LIGHT SNOW ACCUM ACROSS THE FAR NW).

GIVEN THAT FORECAST TEMPERATURES REMAIN VERY MARGINAL, NO
ADVISORIES WERE ISSUED WITH THIS PACKAGE. HOWEVER, WHILE CONFIDENCE
REMAINS LOW AS TO OVERALL IMPACT, A WINTER WX ADVISORY WILL LIKELY
BE NEEDED FOR (AT LEAST) PARTS OF OUR WESTERN CWA. HWO WILL
REFLECT ICING THREAT OVER THESE AREAS LATE TONIGHT AND EARLY
FRIDAY MORNING. LOWS THURS NIGHT U20S-L30S EXCPT 35-40 SERN
COASTAL AREAS.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY/...
-- Changed Discussion --
HIGH PRESSURE QUICKLY RETREATS AS THE LOW TRACKS NE ALONG THE
LOWER MID ATLANTIC COAST FRIDAY. THIS ALLOWS ENOUGH WARM AIR IN
FOR PCPN TO BE ALL RAIN AFTER 15Z FRIDAY. INCREASED POPS TO
CATEGORICAL FOR MOST OF THE AREA...LIKELY POPS ACROSS THE
NORTHWEST. NUMERICAL GUIDANCE CAME DOWN 2-3 CATEGORIES, SO LOWERED
MAXIMA BACK INTO THE U30S NW TO L/M 40S ELSEWHERE.

PCPN ENDS W-E LATE FRI/FRI NIGHT WITH DCRG CLDNS AFTER MIDNIGHT
WRN AREAS. LOWS IN THE 30S TO NR 40 SERN AREAS.

WEAK HIGH PRS BUILDS INTO THE AREA OVER THE WEEKEND. MILDER UNDER
PT TO M SUNNY SKIES. H85 TMPS SUPPORT HIGHS L60S WEST OF THE
BAY...M-U50S ALONG THE COAST. A WEAK COLD FRONT DROPS SOUTH IN
BACKDOOR FASHION LT SAT NGT THROUGH SUN MRNG W/ PSBL SCT PCPN
(RA)...THEN CLRG OUT...BREEZY AND COOLER THE REST OF SUN JUST
SLIGHTLY COOLER, WITH HIGHS STILL SEASONABLE..U50S TO L60S.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
A SEVERAL DAY PD OF MODERATION CONTS LT IN THE WKND THROUGH MID NEXT
WK. DRY/MILD WX MON/TUE. BY WED...BOTH THE GFS AND ECMWF (THOUGH
GFS RMNS MORE DISORGANIZED AT THIS PT) CONTG TO SHOW PTNTL SRN
STREAM STM APPROACHING FM THE W. UNLIKE PREV SYS...COLD AIR WILL
BE LMTD...AND THE TRACK MAY BE MORE OF AN INLAND ONE THAN NR/ALG
THE CST. WILL BRING IN INCRSG CLDNS AND RETURN OF AT LEAST CHC
POPS (RA) ON WED.

&&

.AVIATION /10Z THURSDAY THROUGH MONDAY/...
HIGH PRESSURE MOVING OVER NEW ENGLAND WILL EXTEND SOUTHWARD OVER
THE REGION AS A LOW PRESSURE SYSTEM DEVELOPS OVER FLORIDA AND THE
SOUTHEAST COAST TODAY. A STRONG TEMPERATURE AND PRESSURE GRADIENT
WILL RESULT IN GUSTY NE WINDS TODAY THROUGH FRIDAY AS THE LOW
APPROACHES THE MID ATLANTIC COAST TONIGHT...THEN JUST OFFSHORE ON
FRIDAY. INFRARED SATELLITE IMAGERY INDICATES THAT THE LOW STRATUS
EXPECTED TO MOVE INTO COASTAL AREAS/TAF SITES FROM THE OCEAN IS
FARTHER EAST THAN ORIGINALLY ANTICIPATED. HAVE THEREFORE DELAYED
THE INFLUX OF LOWER CIGS UNTIL 06/1200Z. DESPITE THE INCOMING
STRATUS DECK...WEATHER CONDITIONS WILL REMAIN DRY TODAY.
PRECIPITATION MOVES INTO THE AREA FROM THE SOUTH THIS EVENING AND
WILL OVERSPREAD THE REGION BY LATE FRIDAY MORNING...THEN MOVING
OFFSHORE BY SATURDAY MORNING. PRECIP WILL PRIMARILY FALL AS
RAIN...HOWEVER COLDER AIR NORTHWEST OF AN AVC-RIC-SBY LINE WILL
ALLOW FOR A WINTRY MIX OF SLEET AND FREEZING RAIN TONIGHT INTO
EARLY FRIDAY MORNING. IMPROVING CONDITIONS ARE EXPECTED FROM WEST
TO EAST FRIDAY NIGHT AS LOW PUSHES OUT TO SEA AND HIGH PRESSURE
RETURNS.

&&

.MARINE...
-- Changed Discussion --
A STRONG SFC HIGH PRESSURE MOVES OVER NEW ENGLAND TODAY AND WILL
EXTEND SOUTHWARD INTO THE MID ATLANTIC REGION. MEANWHILE...A LOW
PRESSURE SYSTEM DEVELOPS OVER FLORIDA AND THE SOUTHEAST COAST. A
STRONG TEMPERATURE AND PRESSURE GRADIENT BTWN THESE FEATURES WILL
PRODUCE STRONG NE WINDS TODAY THROUGH FRIDAY AS THE LOW APPROACHES
THE MID ATLANTIC COAST TONIGHT...THEN MOVES JUST OFF THE COAST ON
FRIDAY. SPEEDS WILL AVERAGE 20-30 KT...HOWEVER STRONGER WINDS GUSTS
AROUND 35 KT SHOULD BE ANTICIPATED ON THE OCEAN FROM PARRAMORE
ISLAND TO CURRITUCK LIGHT THIS EVENING INTO FRIDAY. AS WINDS
INCREASE...SO WILL WAVES/SEAS. NEARSHORE SEAS ARE CURRENTLY 7-8 FT
AND WILL INCREASE TO ROUGHLY 8-13 FT AS THE SOUTHEAST LOW PRESSURE
MOVES CLOSER TO THE MID ATLANTIC COAST OVERNIGHT TONIGHT. WAVES ON
CHES BAY ARE CURRENTLY AVERAGING 3-5 FT AND WILL INCREASE TO 4-6 FT
BY THIS AFTN. IN ADDITION...RAIN WILL MOVE INTO THE SRN WATERS
TONIGHT AND WILL SPREAD NWD OVER ALL WATERS BY FRIDAY MORNING.
STRONG SCA FLAGS WILL REMAIN IN EFFECT TODAY THROUGH FRIDAY
NIGHT...WHILE A GALE WARNING FOR THE COASTAL WATERS FROM PARRAMORE
ISLAND TO CURRITUCK LIGHT WILL GO INTO EFFECT EARLY THIS EVENING.

WINDS TURN TO THE NORTH DURING FRI AFTN AS THE LOW BEGINS TO MOVE
AWAY FROM THE MID ATLANTIC COAST AND OUT TO SEA. SPEEDS ARE NOT
EXPECTED TO DIMINISH BELOW SCA THRESHOLDS UNTIL LATE FRI NIGHT/EARLY
SAT MORNING. AFTER WHICH...CONDITIONS IMPROVE AND WINDS BECOME
LIGHT. A PERIOD OF MODERATE LOW LEVEL COLD AIR ADVECTION AND ANOTHER
BRIEF ROUND OF SCA CONDITIONS ARE EXPECTED ON SUNDAY.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
-- Changed Discussion --
TIDAL DEPARTURES XPCD TO RISE TO 1 TO 1.5 FT ABV NORMAL ALG THE OCN
AND IN THE BAY FM THU THROUGH FRI. NO FLOODING XPCD ATTM DUE TO
DCRSG ASTRO TIDE LVLS. WILL NEED TO MONITOR FOR PSBL STRONGER PD OF
WNDS (LT THU INTO FRI MRNG) WHICH MAY RESULT IN DEPARTURES RISING
CLOSER TO 2 FT (AND THAT WOULD APPROACH MINOR THRESHOLDS IN SOME
PLACES).
-- End Changed Discussion --

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ630>638-
     650-652.
     SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ654-
     656-658.
     GALE WARNING FROM 6 PM THIS EVENING TO MIDNIGHT EST FRIDAY
     NIGHT FOR ANZ654-656-658.

&&

$$
SYNOPSIS...MPR
NEAR TERM...MAM
SHORT TERM...MPR/MAM
LONG TERM...ALB
AVIATION...BMD
MARINE...BMD
TIDES/COASTAL FLOODING...AKQ