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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 161836
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
236 PM EDT THU MAY 16 2013

.SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE REMAINS OFF THE COAST THROUGH THIS EVENING. A WEAK
FRONT MOVES SOUTH ACROSS VIRGINIA OVERNIGHT INTO FRIDAY
AFTERNOON...THEN STALLS OVER NORTH CAROLINA THROUGH THE WEEKEND.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
SFC HI PRES RMNS OFF THE SE CONUS CST...WHILE A WK (ILL-DEFINED)
SFC BNDRY IS DRAPED E-W INVOF MD/PA BORDER WWD INTO SRN OH VLY.
VRY WARM AIR S OF THE BNDRY W/ MNLY WSWLY WNDS (A LTL GUSTY AT
TIMES TO ABT 20 MPH). CNVTN BEGINNING TO FIRE INVOF NW VA...JUST
NNW OF CHO...W/ ONLY ISOLD PCPN FOUND TO THE ENE INTO THE INTR
PORTION FO THE LWR MD ERN SHR. CNVTN HIGH BASED (~7KFT) AND
MODIFIED SOUNDINGS ACRS NRN PORTIONS OF FA SHOWING INVERTED V IN
LWR LVLS (TO ARND 850MB). SLGT POOLING OF DEWPTS (U50S) ACRS NRN VA
SO FAR THIS AFTN. ALSO...FREEZING LVL 11.5 TO 12KFT...WILL NEED
CORES OF ANY STMS TO AOA 30KFT FOR STRONG/SVR PTNTL. LMTG FACTOR
IS DP LYRD/DOWNSLOPING W WNDS PTNTLLY MAKING IT DIFFICULT FOR STM
UPDRAFTS TO RISE SUBSTANTIALLY. MAIN THREATS - GUSTY WINDS AND
HAIL. 17Z/16 RUC GENLY HAS DECENT HANDLING ON STM DVLPMNT
ATTM...AND HV FOLLOWED FOR EVE CNVTV POPS (WHICH CONFINES STMS TO
AREAS ALG-N OF A FVX TO WAL LN). S OF THAT LN ISOLD STMS AT
BEST...BUT RIGHT NOW PROB TOO LO FOR POPS ANY HIGHER THAN 14%.

AFT EVE STMS...BNDRY SINKS S THROUGH VA AND WINDS TURN MR NLY AFT
MDNGT. LINGERING SHRAS AFT MDNGT...THOUGH POPS AOB 20% THROUGHOUT.
LO TEMPS MNLY IN THE L/M60S.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY/...
FRNTL BNDRY SLOWLY DRIFTS S ACROSS SRN VA TONITE. ENUF SPRT TO KEEP
LOW CHC POPS...MAINLY IN THE EVE ALTHOUGH SOME SHWR ACTIVITY MAY
LINGER IVOF BNDRY AFTR MIDNITE. LOWS 60-65.

MODELS PROG FRNTL BNDRY TO STALL INVOF NRN NC LATE FRI THROUGH
SAT. MEANWHILE...SFC HIGH PRS MOVG ACROSS NEW ENGLAND LEADS TO
ONSHR WINDS. UPSHOT...AN UNSETTLED PRD XPCTD WITH SKIES VRBLY TO M
CLDY WITH PERIODIC PCPN CHCS. LOWEST POPS ACROSS ERN SHORE AND NRN
NECK AS DRYER AIR MOVES SOUTH FROM HIGH PRS TO THE NRTH. HIGHEST
POPS ACROSS WEST AND SRN AREAS CLOSER TO THE FRNT. MSTR INCRS FROM
THE WEST SAT ENHANCING PCPN CHCS ON ACROSS WRN CNTYS.

FRIDAYS TMP FCST A BIT TRICKY. ALL DEPENDS ON FRNTL LCTN AND PCPN.
HIGHS M-U70S CSTL AREAS...80-85 WEST OF BAY. LOWS FRI NITE 55-60.
HIGHS SAT L-M70S...XCPT 75-80 SRN MOST CNTYS.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
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 /19Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE CONTINUES TO TRACK THROUGH THE NORTHEAST TODAY AS AN
ATTENDANT COLD FRONT SLOWLY SAGS SWD INTO THE MID ATLANTIC. EXPECT
W/SW WINDS GENERALLY AROUND 10 KT WITH GUSTS UP TO 15 KT. AS THE
FRONT DROPS INTO NRN VA...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. HOWEVER...CONFIDENCE IN TIMING
AND PLACEMENT OF ANY STORMS IS NOT HIGH ATTM...SO HAVE ONLY
INCLUDED TEMPO GROUP MENTIONING RAIN SHOWERS.

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...BUT REMAIN AOB 10 KT. 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.

&&

.MARINE...
LATEST SFC OBS SHOW SW WINDS OVER THE WATERS WITH SPEEDS GENERALLY
AROUND 15 KT. SEAS OVER THE NRN COASTAL WATERS RUNNING 3 TO 5 FT.
PRESSURE GRADIENT HAS BEGUN TO RELAX BETWEEN HIGH PRESSURE OFF THE
SE COAST AND LOW PRESSURE TRACKING ACROSS SE CANADA...BUT SPEEDS OF
25 TO 30 KT OBSERVED (KWAL SOUNDING) ABOUT 1K OFF THE SFC OF THE
WATER. PRESSURE GRADIENT WILL CONTINUE TO RELAX THROUGH THIS
MORNING...ALLOWING SPEEDS TO DIMINISH AOB 10 KT THROUGH THE
AFTERNOON. SEAS WILL ALSO FALL AOB 3 FT. WITH THAT SAID...HAVE
DROPPED SCA HEADLINES FOR THE BAY...BUT SPEEDS AROUND 15 KT WILL
CONTINUE THROUGH MID MORNING. SCA HEADLINES WILL CONTINUE FOR THE
NRN COASTAL ZONES THROUGH 7AM FOR HIGH SEAS. WINDS WILL SLOWLY BACK
TO THE W THIS AFTERNOON IN ADVANCE OF A BACKDOOR COLD FRONT. THE
COLD FRONT WILL SLOWLY PROGRESS SWD INTO NRN VA TODAY...CROSSING THE
WATER TONIGHT INTO FRIDAY. WINDS WILL BACK TO THE W/NW TO N/NE
FRIDAY...BUT REMAIN SUB SCA. THE COLD FRONT WILL STALL OVER THE
CAROLINAS THIS WEEKEND BEFORE LIFTING NWD AS A WARM FRONT THE
BEGINNING OF NEXT WEEK. E/SE WINDS LESS THAN 15 KT ARE EXPECTED OVER
THE WEEKEND.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.

&&

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