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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 232002
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
402 PM EDT THU MAY 23 2013

.SYNOPSIS...
-- Changed Discussion --
A COLD FRONT WILL PASS THROUGH THE MID ATLANTIC OVERNIGHT INTO
FRIDAY MORNING. HIGH PRESSURE RETURNS TO THE AREA LATE FRIDAY INTO
THE WEEKEND WITH DRIER CONDITIONS AND COOLER TEMPERATURES
EXPECTED.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
WIDESPREAD SHWRS AND TSTMS WILL CONTINUE THRU THE AFTN AND EVENG
HRS ACROSS THE MID ATLANTIC AHEAD OF AN APPROACHING MID-LVL TROF
AND ASSOCIATED COLD FRNT. PRECIP MAY NOT OCCUR EVERYWHERE (POPS
ARE 70-80%) BUT IT IS EXPECTED TO BE FOCUSED ALONG A LEE TROF
CURRENTLY BISECTING THE AREA N-S AND FURTHER SOUTH INTO NC. PRECIP
NOW WEST OF THE AREA WILL ALSO ADVANCE INTO WESTERN PORTIONS OF
THE FA. AS FAR AS THE SVR THREAT...NOT EXPECTING ANY WIDESPREAD
SVR WX...WITH MARGINAL SHEAR AND WEAK MID-LVL LAPSE RATES...CAPE
AND FORCING. AN ISO STRONG STORM IS PSBL HOWEVER ESPECIALLY NW OF
RIC WHERE 0-6 KM SHEAR WILL APPROACH 30 KT. HEAVY RAIN AND
LOCALIZED FLOODING WILL BE A GREATER THREAT WITH NEAR MOIST
ADIABATIC SOUNDINGS...DEEP MOISTURE IN PLACE (PWAT NEAR 1.7 IN)
AND FAIRLY UNIDIRECTIONAL WINDS.

THE RAIN WILL END FROM WEST TO EAST TNGT/FRI MRNG AS THE COLD FRNT
CROSSES THE AREA. NOT EXPECTING SKIES TO COMPLETELY CLR
OUT...WITH MOISTURE STILL IN PLACE ALOFT FOLLOWING THE SFC FROPA.
LO TEMPS TNGT IN THE LO TO MID 60S.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY/...
-- Changed Discussion --
AFOREMENTIONED MID-LVL TROF SLIDES THRU THE MID ATLANTIC FRI
AFTN...AND WITH DECENT MOISTURE STILL FROM 950-700 MB WILL
MAINTAIN A 20-30% CHC FOR SHWRS ALONG AND EAST OF I-95.
OVERALL...EXPECT A DRYING TREND AS THE TROF PULLS OFFSHORE AND
STRONG CAA WORKS INTO THE AREA. A PRTLY CLDY SKY IN THE AFTN WITH
NOTICEABLY COOLER TEMPS...HIGHS ONLY IN THE LO TO MID 70S.

SFC HI PRES SLOWLY BLDS IN FROM THE WEST OVER THE WEEKEND AS NWRLY
CAA FLOW CONTINUES. CONTINUED COOLER TEMPS (HIGHS IN THE LO TO MID
70S AND LOWS IN THE MID 40S TO LWR 50S). THIS IS ALMOST 10 DEGREES
BLO NORMAL FOR LATE MAY.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
-- Changed Discussion --
HV GONE CLOSE TO A ECMWF/HPC(WPC) BLEND WITH THIS PERIOD, WHICH
YIELDS ONLY MINOR CHANGES TO MEDIUM RANGE FORECAST. GFS HAS STARTED
TO CATCH ON TO ECMWF`S SLOWER SOLUTION WRT PROGRESS OF CLOSED UPPER
LEVEL LOW OVER THE NORTHEAST AND ATLANTIC CANADA. THIS SLOWER
SOLUTION ALLOWS FOR A SLOW WARMUP THROUGH THE PERIOD. IT WILL ALSO
ALLOW FOR CONTINUED NW FLOW ACROSS THE SOUTHERN MID-ATLANTIC SUNDAY
AND MONDAY. LOW (SLIGHT CHANCE) POPS REMAIN IN PLACE FOR MEMORIAL
DAY AFTN/EVENING AND AGAIN ON TUESDAY AS A WEAK DISTURBANCE/MID
LEVEL TROUGH DROPS ACROSS THE REGION WHILE A WARM FRONT LIFTS NORTH
ACROSS THE MISSOURI/LOWER OHIO VLYS.

BY MIDWEEK, THE FRONT SHUNTS NORTH OF THE AREA. MID-UPPER LEVEL
RIDGING REBUILDS ACROSS THE EASTERN HALF OF THE CONUS AS SFC HIGH
SLIDES OFF THE MID-ATLANTIC COAST. RESULTANT BERMUDA
HIGH/"SUMMERLIKE" SETUP WILL ALLOW FOR INCREASING TEMPS (AND
HUMIDITY VALUES) FOR THE MID TO LATTER PART OF NEXT WEEK. RAINFALL
OPPORTUNITIES DURING THIS PERIOD WILL PRIMARILY BE DIURNALLY DRIVEN,
WITH LITTLE MORE THAN PARTLY CLOUDY AND INCREASINGLY MUGGY
CONDITIONS BY NIGHT.
-- End Changed Discussion --

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
SCATTERED SHOWERS AND EMBEDDED THUNDERSTORMS WILL CONTINUE TO
DEVELOP ALONG A LEE SIDE TROUGH OVER CNTRL VA/NE NC THIS
AFTERNOON. THIS IN ADVANCE OF A COLD FRONT...LOCATED OVER THE
OH/TN VALLEYS AS OF 2 PM EDT. VFR/MVFR CIGS AS LOW AS 1500 TO
2500 FT AGL...WITH LOCALIZED IFR CIGS OVER THE LOWER ERN
SHORE...WILL PREVAIL THIS AFTERNOON. S WINDS GENERALLY 10 KT WITH
A FEW GUSTS UP TO 20 KT. THUNDERSTORM ACTIVITY SHOULD MOSTLY BE
CONFINED TO INLAND VA AND NC DURING AFTERNOON HEATING. ATMOSPHERE
REMAINS MORE STABLE NEAR THE COAST DUE TO EARLIER SHOWERS AND
CLOUD COVER. MAIN IMPACTS TO AVIATION OPERATIONS WILL BE LOCALLY
HEAVY RAINFALL (MVFR/IFR VSBYS POSSIBLE) AND GUSTY WINDS.
THUNDERSTORM COVERAGE WILL DIMINISH WITH THE LOSS OF DAYTIME
HEATING...BUT EXPECT SCATTERED SHOWERS TO CONTINUE TONIGHT.

FRONT WILL CROSS THE REGION TONIGHT...CLEARING THE COAST EARLY
FRI MORNING. WINDS WILL INCREASE FROM THE NW POST FRONTAL FRI
MORNING AND FRI AFTERNOON. A FEW LINGERING SHOWERS WILL BE
POSSIBLE...MAINLY ALONG THE COAST FRIDAY MORNING. OTHERWISE...VFR
CONDS FRI. HIGH PRESSURE WILL THEN BUILD INTO THE REGION OVER THE
WEEKEND.

&&

.MARINE...
-- Changed Discussion --
LATEST OBS REFLECT S-SW FLOW ~15-20 KT WITH OCCASIONAL GUSTS TO 25
KT IN THE LOWER BAY. SCA FLAGS HAVE BEEN RAISED FOR THE CURRITUCK
SOUND...AND CONTINUE FOR THE BAY...THROUGH THIS EVENING AS GRADIENT
TIGHTENS AHEAD OF APPROACHING COLD FRONT. WINDS VEER TO THE W-NW
AND DIMINISH SLIGHTLY OVERNIGHT, BUT QUICKLY RAMP BACK UP AS COLD
FRONT CROSSES THE REGION FROM THE NW LATE TONIGHT. WIND QUICKLY
INCREASES BY LATE MORNING FRI THROUGH ERY SAT IN MOD LLVL CAA
(20-25KT W/GUSTS TO ~30KT). HAVE HOISTED SCA FOR THE EASTERN VA
RIVERS FOR THIS PERIOD.

GOOD MODEL AGREEMENT W/ DEVELOPMNT/LOCATION OF LOW PRESSURE OFF
NJ/SRN NEW ENG COAST FRI NGT INTO SAT. THE LOW WL BE SLOW TO LIFT TO
THE NE SUN INTO MON...RESULTING IN ONLY GRADUAL IMPROVEMENT (SCA PER
WAVEWATCH POTENTIALLY TO LINGER OVR THE NRN OCN WTRS INTO LATE SAT).
AS PER POLICY WL AVOID "DOUBLE HEADLINE" ISSUANCE, BUT ADDITIONAL
SCA FLAGS WILL BE NECESSARY IN THE CHES BAY AND SOUTHERN COASTAL
WATERS AFTER CURRENT HEADLINES EXPIRE. PERIOD OF SCA WL BE FOR LATE
FRI MORNING/AFTN THROUGH EARLY SATURDAY. CONDITIONS BECOME SUB-SCA
WITH WINDS DIMINISHING AOB 15KT SUNDAY THROUGH TUESDYA AS HIGH
PRESSURE BUILDS ACROSS THE WATERS LATE IN THE HOLIDAY WEEKEND.
-- End Changed Discussion --

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ630>632-
     634.
     SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ650-652-654.
     SMALL CRAFT ADVISORY UNTIL 7 AM EDT FRIDAY FOR ANZ656-658.

&&

$$
SYNOPSIS...MAS
NEAR TERM...MAS
SHORT TERM...MAS
LONG TERM...MAM
AVIATION...SAM
MARINE...MAM