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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 160531
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
131 AM EDT THU MAY 16 2013

.SYNOPSIS...
HIGH PRESSURE REMAINS CENTERED OFF THE MID ATLANTIC COAST THROUGH
FRIDAY. A WEAK FRONT APPROACHES THE AREA FROM THE NORTH THURSDAY
AFTERNOON THEN SETTLES OVER THE AREA FRIDAY INTO THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
THE LATEST SURFACE ANALYSIS INDICATES A ~1022MB SURFACE HIGH
CENTERED OVER THE EAST-CENTRAL GULF COAST, WITH A SURFACE RIDGE
AXIS EXTENDING NE JUST OFF THE SOUTHEAST COAST. ALOFT, A RATHER
PROGRESSIVE NORTHERN STREAM FLOW EXISTS, WITH QUASI-ZONAL FLOW
ACROSS THE NORTHERN TIER OF STATES. MEANWHILE, WEAK SHORTWAVE
RIDGING HAS DEVELOPED ACROSS THE SOUTHEAST AHEAD OF CLOSED UPPER
LOW WHICH CONTINUES TO SLOWLY MEANDER ACROSS THE SOUTHERN PLAINS.

A WEAK DISTURBANCE DROPPING SE OF THE LOWER GRT LAKES HAVE
TRIGGERED A FEW ISOLATED SHRAS THIS EVENING, MAINLY ALONG AND
JUST SOUTH OF THE MASON-DIXON LINE INVOF FNTL BNDRY DRAPED NW-SE
FM SOUTH CENTRAL PA TO OH VLY THIS EVE. HRRR CONTINUES TO WEAKEN
THIS ACTIVITY JUST TO OUR NORTH, THOUGH POTENTIAL DOES EXIST FOR
AN ISOLATED SHRA OR TWO OVER FAR NORTHERN PART OF DORCHESTER,
WICOMICO, AND WORCESTER COUNTIES (US-50 AND NORTH) THROUGH ABOUT
6Z/2A OR SO BEFORE IT AND THE ASSD WARM FRONT CLEAR THE NORTHERN
MID-ATLANTIC COAST LATE TONIGHT. OTHERWISE, LOOK FOR A MILD,
COMFORTABLE OVERNIGHT, UNDER A CLEAR TO PARTLY CLOUDY SKY. EARLY
MORNING LOW TEMPS MAINLY IN THE L/M60S.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
FNTL BNDRY FM THE N BEGINS TO PUSH SLOLY S THU...REACHING NRN
AREAS OF FA IN THE AFTN...THEN TO THE S THU NGT INTO FRI. NOT THE
BEST FORCING OR DYNAMICS FOR ORGANIZED CNVTN...THOUGH SOME POOLING
OF SFC-LO LVL DEWPTS COMBINED W/ HEATING PTNTLLY ENOUGH FOR
ISOLD/SCT CNVTN. WILL CARRY 20-40% POPS ACRS THE FA THU AFTN INTO
THU NGT. THE BNDRY SHIFTS S TO NR OR JUST S OF THE NC/VA BRDR ON
FRI...W/ PSBL FOCUS FOR ANY PCPN FM CNTRL/SRN VA INTO NE NC. WHILE
ENOUGH TIME FOR DECENT WRMG ON THU (BEFORE THE BNDRY REACHES THE
FA)...WILL BE ABLE TO HAVE TEMPS REACH THE 80S XCP RIGHT AT THE
CST (ON THE ERN SHR). PSNY THU...THEN VRB CLDS OR MCLDY THU NGT
INTO FRI.

THE BNDRY TO RMN NRLY STNRY INVOF NRN NC LT FRI THROUGH SAT. SFC
HI PRES PASSING BY N AND THROUGH NEW ENG WILL LEAD TO ONSHR
WINDS...CONTD VRB CLDS OR MCLDY CONDS AND LO PROB FOR PCPN. HI
TEMPS SAT FM ARND 70F AT THE CST...TO MNLY THE M/U70S INLAND.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A WEAK FRONTAL BOUNDARY WILL LINGER ACROSS THE MID-ATLANTIC SUNDAY.
THIS IS IN ADDITION TO A WEAK UPPER DISTURBANCE PASSING OVERHEAD
WILL PRODUCE A CHANCE FOR SHOWERS AND THUNDERSTORMS. AN H5 RIDGE
AXIS BUILDS OVER THEN EASTERN U.S. MON-WED OF NEXT WEEK. MODELS SHOW
A LOT OF UNCERTAINTY AS TO JUST HOW MUCH SHOWER/TSTM ACTIVITY WILL
OCCUR EARLY NEXT WEEK. DUE TO A LACK OF A TRIGGER TO GET ORGANIZED
TSTMS GOING...WILL LIMIT PCPN CHANCES TO THE 20-30% RANGE REACH DAY.
TEMPS WILL REMAIN ON THE WARM/MILD SIDE THROUGH THE PERIOD WITH
HIGHS IN THEN 70S AND 80S AND LOWS IN THE 60S.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
LOW PRESSURE WILL TRACK THROUGH SE CANADA TODAY AS AN ATTENDANT
COLD FRONT SLOWLY SAGS SWD INTO THE MID ATLANTIC. HIGH PRESSURE WILL
REMAIN OFF THE SOUTHEAST COAST. GENERALLY CLEAR SKIES THIS
MORNING...EXCEPT MID/UPPER LEVEL CLOUDS ASSOCIATED WITH THE FRONT
MOVING ACROSS NRN VA AND THE MD ERN SHORE. SW WINDS GENERALLY AOB
10 KT THIS MORNING WITH A FEW GUSTS UP TO 25 KT ALONG THE
IMMEDIATE COAST. FOR TODAY...NOT AS BREEZY AS WEDS AFTERNOON WITH
W/SW WINDS GENERALLY AROUND 10 TO 15 KT WITH GUSTS UP TO 20 KT. AS
THE FRONT DROPS INTO NRN VA THIS AFTERNOON...ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON INTO
THIS EVENING ACROSS THE REGION...GENERALLY NORTH OF THE NC/VA
BORDER. MVFR/IFR VSBYS POSSIBLE IN THUNDERSTORMS WITH GUSTS UP TO
35 KT. HOWEVER...CONFIDENCE IS NOT HIGH ATTM DUE TO LACK OF
COVERAGE...SO WILL NOT INCLUDE IN TAFS.

THE COLD FRONT WILL CONTINUE TO SLOWLY PROGRESS SWD...CROSSING THE
REGION LATE TONIGHT THROUGH FRIDAY. WINDS WILL BACK FROM THE W/SW
TO THE NW BEHIND THE FRONT. SHOWERS AND THUNDERSTORMS WILL AGAIN
BE POSSIBLE FRI AFTERNOON/EVENING...MAINLY ACROSS SRN VA/NRN NC.
THE FRONT WILL STALL OVER THE CAROLINAS THIS WEEKEND...WITH
ADDITIONAL SHOWERS AND THUNDERSTORMS POSSIBLE.
-- End Changed Discussion --

&&

.MARINE...
S-SW FLOW CONTINUES ACROSS THE MARINE AREA THROUGH LATE THIS EVENING
WITH MARGINAL SMALL CRAFT CONDITIONS (SAVE THE SOUTHERN COASTAL
WATERS). WILL LEAVE CURRENT HEADLINES UNCHANGED. WINDS TURN SW TO W
LATE TONIGHT AND DECREASE IN ADVANCE OF A BACKDOOR COLD FRONT THAT
SLOWLY SAGS SOUTHWARD THURS...CROSSING THE WATERS THURS NIGHT INTO FRI
BEFORE STALLING OVER THE CAROLINAS. WINDS WILL SHIFT FROM THE SW TO
THE N/NE POST FRONTAL...BUT EXPECTED TO REMAIN BELOW SCA THRESHOLDS.
E-SE WINDS LESS THAN 15 KT ARE EXPECTED OVER THE WEEKEND.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT EARLY THIS MORNING FOR
     ANZ630>632-634.
     SMALL CRAFT ADVISORY UNTIL 7 AM EDT THIS MORNING FOR ANZ650-
     652-654.
-- End Changed Discussion --

&&

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