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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 151106
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
706 AM EDT WED MAY 15 2013

.SYNOPSIS...
A WARM FRONT LIFTS NORTH OF THE REGION THIS MORNING. HIGH PRESSURE
BECOMES CENTERED OFF THE MID ATLANTIC COAST THROUGH FRIDAY. A WEAK
FRONT APPROACHES THE AREA FROM THE NORTH THURSDAY AFTERNOON THEN
SETTLES INTO THE AREA FRIDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST MSAS SHOWING WARM FRNT NW OF THE RGN WITH SFC HIGH PRES
CENTERED ALONG GULF COAST. MODELS IN AGREEMENT IN LIFTING WRM
FRNT N OF RGN THIS MORNING ALLOWING MID LVL RIDGE TO BUILD IN.
BKN-OVC BAND OF MID LVL CLOUD DECK (BTWN 8-12K FT) LINGERING
ACROSS ERN HALF OF FA WITH ANY LEFT OVER LGT SHWRS / SPRNKLS NOW
LIMITED TO LWR MD ERN SHORE. ALL THIS SHIFTS N OF RGN AFTR 12Z
WITH TSCTNS SHOWING DCRG CLDNS THIS MORN AND ONLY SCT CLOUDS ACROSS
THE RGN BY THE AFTRN. TIGHTENING PRS GRDNT AHEAD OF APPRCHG FRNTL
BNDRY FROM THE WEST RESULTS IN A RTHR BREEZY DAY AHEAD (15-25 MPH).
H85 TMPS RISE TO 18-20C OVR THE PIEDMONT (DEPENDING ON MODEL OF
CHOICE). COMBO OF THIS WITH STRNG MAY SUN AND A DOWNSLOPING WND
RESULTS IN A DAY ABT 20 DEGREES WRMR THAN YSTRDY. HIGH TMPS 80-85
ALONG THE COAST...M-U80S FROM THE CHES BAY TO THE I95-I64 CORRIDORS...
ARND 90 OVR SWRN PIED.

AIRMASS OVR FA LOOKS TO BE CAPPED FOR MOST OF THE DAY SO NO PCPN
XPCTD. LINE OF CONVECTION PROGGED TO DVLP WELL N OF FA THIS AFTRN
THEN TRACK SE TOWARD THE LWR MD ERN SHORE AFTR 20Z. KEPT A SLGHT CHC
POPS THERE BTWN 21Z-00Z GIVEN MODEL DIFFERENCES IN TIMING.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
WEAK FRNTL BNDRY PROGGED TO STALL N OF FA TONITE. BEST SPRT FOR ANY
EVENING CONVECTION WILL BE ACROSS LWR MD ERN SHORE SO WILL CARRY
CHC POPS FOR NOW. OTW...A PT CLDY & WRM NITE. LOWS IN THE M-U60S.

HIGH PRS MOVG SE FROM CANADA PUSHES THIS BNDRY SOUTH INTO AKQ FA
THURS. BNDRY IS FCSTD TO STALL OVR SRN HALF OF FA BY FRI AS IT
ENCOUNTERS THE STRNG RIDGE TO THE S. THIS BNDRY TO BE THE TRIGGER
FOR MAINLY AFTRN / EVE CONVECTION EACH DAY. HIGHEST POPS THURSDAY
30-40% FA WIDE WITH HIGHEST POPS ACROSS SRN HALF OF FA FRI. DON`T
SEE ANY SVR THREAT ATTM...BUT SOME LCLLY HEAVY DOWNPOURS PSBL DUE
TO SLOW MOVMNT OF ANY STORMS THAT DVLP. HIGHS THURS L-M80S ALONG THE
COAST WITH M-U80S W OF CHES BAY. LOWS THURS NITE IN THE U50S LWR MD
ERN SHORE (BEHIND FRNT)...L-M60S ELSEWHERE. A BIT COOLER FRI DUE
TO MORE CLDS AND FRNTL PSN. HIGHS 80-85 XCPT U70S-L80S CSTL AREAS.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
STILL SOME UNCERTAINTY THROUGHOUT THE EXTENDED PERIODS REGARDING
SMALLER SCALE FEATURES...HOWEVER THE OVERALL MESSAGE REMAINS THE
SAME. SFC HIGH PRESSURE AND UPPER LEVEL RIDGING DOMINATE THE WEATHER
PATTERN WITH WARM AIR ADVECTING IN THE REGION FROM THE SW.

IN REGARD TO TEMPERATURES...SATURDAY APPEARS TO BE THE COOLEST DAY
IN THE LONG RANGE FORECAST AS AN UPPER LEVEL TROUGH CROSSES NRN NEW
ENGLAND AND HIGH PRESSURE AT THE SFC BRINGS A BRIEF COOL DOWN TO THE
REGION. SAT HIGHS IN THE LOWER 80S...LOW-MID 70S ALONG THE IMMEDIATE
COAST DUE TO PERSISTENT ONSHORE/ELY FLOW. TEMPERATURES ARE EXPECTED
TO SLOWLY REBOUND BY A FEW DEGREES EACH DAY FROM SUN INTO EARLY NEXT
WEEK AS THE UPPER LEVEL RIDGE MOVES OVER THE ERN SEABOARD. HIGHS
GENERALLY IN THE LOW-MID 80S (MID-UPPER 70S IMMEDIATE COAST) WITH
LOWS SAT-MON GENERALLY IN THE LOW-MID 60S.

IN REGARD TO PRECIPITATION...VARIOUS SHORTWAVES/MOISTURE PASSING
THROUGH W-NW FLOW ALOFT...IN ADDITION TO DIFFERING LONG RANGE MODEL
SOLUTIONS...WILL MAKE IT DIFFICULT TO NAIL DOWN EXACT TIMING OF
POTENTIAL SHOWERS AND THUNDERSTORMS. WILL THEREFORE CARRY A CHANCE
FOR AFTN/EVENING THUNDERSTORMS WITH LIGHT RAIN SHOWERS DURING THE
OVERNIGHT AND MORNING TIMEFRAMES FOR FRI NIGHT THROUGH MON.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
MID/UPPER LEVEL CLOUDS WILL CONTINUE TO SPILL INTO THE REGION IN
NWLY FLOW TODAY. A WARM FRONT WILL LIFT SW TO NE OVER THE REGION
LATE THIS MORNING INTO THIS AFTERNOON. SW WINDS WILL INCREASE AS
THE FRONT LIFTS...WITH OCCASIONAL GUSTS UP TO 25 KT. WINDS WILL
DIMINISH THIS EVENING AND OVERNIGHT. MIXING AND CLOUD COVER WILL
PREVENT FOG DEVELOPMENT OVERNIGHT.

A BACK DOOR COLD FRONT WILL SLOWLY DRIFT SWD THROUGH THE END OF
THE WEEK...CROSSING THE FA THURS AFTERNOON BEFORE STALLING OVER NC
THE BEGINNING OF THE WEEKEND. ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE EACH AFTERNOON AND EVENING THROUGH
THE END OF THE WEEK.
-- End Changed Discussion --

&&

.MARINE...
HIGH PRESSURE REMAINS CENTERED OVER THE NRN GULF OF MEXICO...WITH A
SFC RIDGE AXIS EXTENDING NEWD JUST OFF THE CAROLINA COAST. LOW END
SCA SPEEDS OBSERVED OVER THE BAY EARLY THIS MORNING AS A GRADIENT
EXISTS BTWN HIGH PRESSURE TO THE S AND LOW PRESSURE OVER THE GREAT
LAKES. HAVE ALSO RAISED SCA HEADLINES FOR THE LOWER JAMES RIVER AS
SCA SPEEDS ARE OCCURRING. A WARM FRONT WILL LIFT OVER THE WATER LATE
MORNING/EARLY AFTERNOON. WINDS WILL VEER TO THE SW AND INCREASE AS
THE FRONT LIFTS. WHILE WAA WILL EXIST IN THE LOW LEVELS...THERMAL
PROFILES AND CROSS SECTIONS SUGGEST LOW END SCA SPEEDS WILL CONTINUE
OVER THE BAY THROUGH THE AFTERNOON INTO TONIGHT. THERE MAY BE A BRIEF
LULL IN SCA SPEEDS AS THE FRONT LIFTS OVER THE WATER THIS
AFTERNOON...BUT SCA SPEEDS EXPECTED TO RETURN LATE AFTERNOON.
THUS...SCA HEADLINES FOR THE BAY AND LOWER JAMES RIVER HAVE BEEN
EXTENDED THROUGH 1AM EDT THURSDAY. HEADLINES HAVE ALSO BEEN RAISED
FOR THE CURRITUCK SOUND FOR SCA SPEEDS. FOR THE COASTAL
WATERS...EXPECT SPEEDS TO REMAIN JUST BELOW SCA SPEEDS...BUT STRONG
SWLY FLOW WILL BUILD SEAS OVER THE NRN COASTAL ZONES TO 4 TO 6 FT.
HEADLINES WILL RUN FROM EARLY AFTERNOON THROUGH THURSDAY MORNING.

A BACKDOOR COLD FRONT WILL SLOWLY SAG SWD THURS...CROSSING THE WATER
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
SUB SCA CONDS. SUB SCA CONDS EXPECTED TO CONTINUE INTO THE WEEKEND.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EDT THURSDAY FOR ANZ630>632-
     634-638.
     SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 1 AM EDT
     THURSDAY FOR ANZ633.
     SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 7 AM EDT
     THURSDAY FOR ANZ650-652-654.

&&

$$
SYNOPSIS...MPR
NEAR TERM...MPR
SHORT TERM...MPR
LONG TERM...BMD
AVIATION...SAM
MARINE...SAM