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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 231033
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
633 AM EDT THU MAY 23 2013

.SYNOPSIS...
THE COMBINATION OF HIGH PRESSURE OVER THE ATLANTIC AND SOUTHWEST
WINDS WILL CONTINUE TO PULL A WARM AND HUMID AIRMASS INTO THE REGION
THROUGH THURSDAY. A COLD FRONT WILL PASS THROUGH THE MID ATLANTIC
THURSDAY NIGHT INTO FRIDAY MORNING. HIGH PRESSURE RETURNS TO THE
AREA LATE FRIDAY INTO THE WEEKEND WITH DRIER CONDITIONS AND COOLER
TEMPERATURES EXPECTED.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWERS ALONG WITH POCKETS OF ENHANCED CONVECTION SUPPORTING
THUNDER IS CONTINUING ACROSS THE VA PIEDMONT THIS MORNING DUE TO
AND AREA OF WEAK CONVERGENCE.

TEMPS REMAIN WELL ABOVE NORMAL TNGT AS SOUTHERLY FLOW
PERSISTS...LOWS IN THE UPR 60S UNDER A PRTLY TO MSTLY CLDY SKY.
PATCHY FOG IS POSSIBLE BUT LO STRATUS IS EXPECTED. CHCS FOR RAIN
WILL INCREASE THU MORNG AS MOISTURE AND MID-LVL ENERGY EMBEDDED IN
THE SW FLOW ALOFT INCREASES. MEANWHILE...MID LEVEL ENERGY MOVING
AROUND THE PERIPHERY OF A 500MB HIGH LOCATED IN THE ATLANTIC WILL
INCREASE RAIN/THUNDER CHANCES NEAR THE COAST THUR MORNING/AFTN.
AGAIN...MODERATE INSTABILITY WILL BE IN PLACE ACCOMPANIED BY PWATS
AROUND 1.7IN CREATING CONDITIONS THAT WILL SUPPORT HEAVY RAIN AND
OCCASIONAL LIGHTNING.

CHCS FOR RAIN WILL INCREASE THRU THE DAY THU AS DEEP LAYER
MOISTURE INCREASES AND LO PRES APPROACHES FROM THE WEST. NOT
EXPECTING SVR WX HOWEVER AN ISO DAMAGING WING GUST IS PSBL TO THE
WEST AS SHEAR PROFILES INCREASE AHEAD OF AN APPROACHING MID-LVL
TROF. DON`T EXPECT IT TO RAIN THE ENTIRE DAY HOWEVER COVERAGE IS
ENUF TO WARRANT LIKELY (70%) POPS. BEST TIMING FOR HEAVY RAIN/CONVECTION
 WILL BE IN THE AFTN/ERLY EVNG HRS AS MOISTURE INCREASES AND THE
MID ATLANTIC SITS UNDER THE RIGHT ENTRANCE REGION OF AN UPR-LVL
JET STREAK. HI TEMPS GENRLY IN THE LO 80S. READINGS WILL BE A BIT
COOLER NEAR THE COAST.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE RAIN WILL END FROM WEST TO EAST ERLY FRI AS THE COLD FRNT
ADVANCES OFF THE COAST. NOT EXPECTING SKIES TO COMPLETELY CLR
OUT...WITH MOISTURE STILL IN PLACE ALOFT FOLLOWING THE SFC FROPA.

DRIER CONDS EXPECTED BY FRI AFTN (THOUGH KEEPING A CHC FOR SHWRS
OVER ERN AREAS WITH THE UPR-LVL TROF STILL WEST OF THE AREA) AS
SFC FLOW BECOMES NWRLY FOR THE FIRST TIME IN SEVERAL DAYS...AND
TEMPS ONLY REACHING THE LO TO MID 70S IN MOST LOCATIONS. SFC HI
PRES BLDS IN FROM THE WEST ON SAT LEADING TO A MSTLY SNY SKY AND
NOTICEABLY COOLER TEMPS (HIGHS ONLY IN THE LO TO MID 70S).

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
MEDIUM RANGE FORECAST PERIOD CHARACTERIZED BY MODIFIED CANADIAN HIGH
PRESSURE DROPPING NW TO SE ACROSS THE AREA FOR THE LATTER HALF OF
THE MEMORIAL DAY WEEKEND. ALOFT, CLOSED UPPER LEVEL LOW OVER THE
NORTHEAST AND ATLANTIC CANADA WILL SLOWLY LIFT NE SUNDAY, ALLOWING
FOR MODEST HGT RISES ALOFT, AND WITH IT A GENERAL INCREMENTAL
RAMPING UP OF TEMPS THROUGH THE PERIOD. IT WILL ALSO ALLOW FOR
NW FLOW ALOFT ACROSS THE SOUTHERN MID-ATLANTIC SUNDAY AND
MONDAY. LOW (SLIGHT CHANCE) POPS REMAIN IN PLACE FOR MEMORIAL DAY
AFTN/EVENING AS A WEAK DISTURBANCE/MID LEVEL TROUGH DROPS ACROSS
THE REGION AND A SFC WARM FRONT LIFTS NORTH TO THE WEST.

BERMUDA HIGH/SUMMER-LIKE PATTERN RELOADS FOR THE MID TO LATTER
POTION OF THE WEEK, AS MID-UPPER LEVEL RIDGING REBUILDS ACROSS
THE EASTERN HALF OF THE CONUS AND SFC HIGH SLIDES OFFSHORE. RAINFALL
OPPORTUNITIES WILL PRIMARILY BE DIURNALLY DRIVEN MON-WED, WITH
LITTLE MORE THAN PARTLY CLOUDY AND INCREASINGLY MUGGY CONDITIONS
BY NIGHT.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
BKN-OVC MNLY MVFR CIGS THROUGHOUT TDA. SCT SHRAS ATTM ACRS CNTRL
AND SRN VA INTO NE NC CONTG THROUGH REST OF MRNG HRS W/ MVMNT TO
THE NE. VRY LO PROB T INTO MIDDAY HRS. WIDESPREAD MVFR CIGS XPCD
ACRS THE FA MIDDAY INTO THE EVE HRS ALG W/ INCRSG COVERAGE OF
SHRAS/ISOLD-SCT T. PTNTL FOR IFR VSBYS IN HVY RA. RA SLO TO END
THIS EVE...ALG W/ ONLY GRADUAL IMPROVEMENT OF CIGS. GENLY (ANY)
CIGS FRI VFR (ABV 3KFT) ALG W/ DVLPG GUSTY NW WNDS (TO 25-30 KT)
BY AFTN. WNDS SLO TO SUBSIDE INTO SAT. LO PROB MVFR CIGS INVOF CST
FRI NGT INTO SAT AS COASTAL LO PRES SLO TO DVLP (OFFSHORE).
OTRW...VFR CONDS XPCD SAT THROUGH MON.
-- End Changed Discussion --

&&

.MARINE...
PREVAILING S FLO ATTM...AND XPCD INTO TNGT AHD OF NEXT CDFNT.
MARGINAL WINDSPEEDS FOR (LO END) SCAS (MDLS LWR SPDS LTR TDA AS
WIDESPREAD RA ENTERS THE WTRS)...SEAS ON THE OCN GRADUALLY
BUILDING/APPROACHING 5 FT. CDFNT CROSSES THE WTRS FRI MRNG...TO BE
FOLLOWED BY WINDSHIFT TO NW AND INCRS IN SPDS (DUE TO MDT LLVL CAA)
TO SOLID SCAS (20-25 KT...GUSTS TO 30 KT). THESE CONDS TO LAST INTO
SAT AS CSTL LO PRES (OFFSHR) IS SLO TO DVLP. GFS/ECMWF IN GENL
AGREEMENT OVR DVLPMNT AND LOCATION OF THAT STM OF NJ/SRN NEW ENG FRI
NGT INTO SAT. THE LO IS SLO TO LIFT TO THE NE SUN INTO
MON...RESULTING IN ONLY GRADUAL IMPROVEMENT (LASTLY OVR THE NRN OCN
WTRS BY LT IN THE WKND). ONLY CHG TO HEADLINES WILL BE TO EXTEND THE
SCA FOR THE NRN OCN WTRS THROUGH FRI (22Z/24). THERE WILL BE A LULL
IN SPDS (FM LT TDA/TNGT INTO FRI MRNG) BEFORE PASSAGE OF CDFNT SO
HOLD OFF ON ADDING AN ADDITIONAL HEADLINE TO THE BAY/SRN OCN FOR NOW.

&&

.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 FROM 4 PM THIS AFTERNOON TO 7 AM EDT
     FRIDAY FOR ANZ656-658.

&&

$$
SYNOPSIS...BMD
NEAR TERM...BMD/DAP
SHORT TERM...MAS/DAP
LONG TERM...MAM
AVIATION...ALB
MARINE...ALB