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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 231810
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
210 PM 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
TODAY. A COLD FRONT WILL PASS THROUGH THE MID ATLANTIC TONIGHT
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 CONTINUING ACROSS NE NC/SE VA IN ASSOCIATION WITH A MID-LVL
VORT MAX SLIDING UP THE NC COAST. EXPECT COVERAGE AND INTENSITY OF
PRECIP TO INCREASE THROUGH THE DAY AS INSTABILITY INCREASES DUE TO
DAYTIME HEATING AND MOISTURE AND MID-LVL ENERGY EMBEDDED IN THE SW
FLOW ALOFT INCREASES. MODERATE INSTABILITY WILL BE IN PLACE
ACCOMPANIED BY PWATS AROUND 1.7IN CREATING CONDITIONS THAT WILL
SUPPORT HEAVY RAIN AND OCCASIONAL LIGHTNING. NOT EXPECTING
WIDESPREAD SVR WX HOWEVER AN ISO DAMAGING WING GUST IS PSBL
(ESPECIALLY FOR NW AREAS) 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 /18Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
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.
-- 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...
-- Changed Discussion --
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.
-- End Changed Discussion --

&&

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