Area Forecast Discussion
Issued by NWS Wakefield, VA

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000
FXUS61 KAKQ 190010
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
810 PM EDT FRI APR 18 2014

.SYNOPSIS...
HIGH PRESSURE OVER EASTERN NEW ENGLAND SLOWLY RETREATS TO THE
NORTHEAST THROUGH TONIGHT...WHILE LOW PRESSURE TRACKS ACROSS
NORTH FLORIDA. THAT LOW WILL BE SLOW TO MOVE OFF THE SOUTHEAST
COAST THROUGH SUNDAY...AS HIGH PRESSURE BUILDS SOUTH FROM EASTERN.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A COOL AFTN ACRS THE FA W/ VRB CLDS. TOUGH TO FIND EXACT COVERAGE
OF LO LVL CLDNS UNDER THE EXTENSIVE MID/HI LVL CLDNS SPREADING
INTO THE FA FM THE SW. SFC OBS SHOWING THAT THE BULK OF THE SC
RMNS RIGHT AT THE CST.

FOR TNGT...CLDNS WILL CONT TO SPREAD NE FM THE ERN GULF STATES AS
SFC LO PRES SLOLY TRACKS ACRS N FL. WATCHING LGT RA BEGINNING TO
MOVE THROUGH FAR WRN/CNTRL NC SO FAR THIS AFTN...AND THAT RA WILL
CONT TO DO SO THROUGH THE EVE HRS. MDLS (NAM/GFS) DIFFER ON HOW
FAR NNE THE PCPN SHIELD GETS OVRNGT. 12Z/18 ECMWF LEANS IN THE
DIRECTION OF THE GFS AS DOES CURRENT FCST. WILL BLEND ALL THREE
FOR TNGT...IN BRINGING SLGT CHC-CHC POPS N OF THE VA-NC MNLY AFT
MDNGT AND N TO ABT RIC BY LT TNGT. WILL HAVE LIKELY POPS AFT MDNGT
FOR PORTIONS OF NE NC. LO TEMPS MNLY FM THE L/M40S.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
WILL CONT W/ A BLEND OF GFS/ECMWF AND CURRENT FCST FOR PCPN
COVERAGE ON SAT INTO SUN AS LO PRES IS SLO TO MOVE OFF THE SE
CONUS CST. AFT SAT MRNG...XPCG PCPN SHIELD TO GRADUALLY SINK S
INTO SUN AS SFC HI PRES FM ERN CANADA BEGINS TO BUILD S.

GENLY KEPT AREAS N OF A RIC TO WAL DRY FOR THE EVENT BUT W/ MSTLY
CLDY CONDS THROUGH MOST OF SAT. ACRS SRN VA INTO NE NC WILL HAVE CHC
TO LIKELY POPS (HIGHEST IN NE NC)...THOUGH TRENDING DOWN FM SAT AFTN
INTO SUN. SGFNT AMT OF CLDNS XPCD TO RMN OVR MNLY SE VA/NE NC
WELL INTO SUN...WHILE ELSW BECOMES P/MSNY. ONSHORE WNDS WILL RMN
GUSTY NR/AT THE CST.

HI TEMPS SAT FM THE L/M50S AT THE CST TO ARND 60F ACRS INTR SE
VA/NE NC...AND THE M60S WELL INLAND N AND NW OF RIC. LO TEMPS FM
THE L/M40S INLAND TO ARND 50F AT THE CST IN SE VA/NE NC. HI TEMPS
SUN FM 55 TO 60F AT THE CST TO THE M/U60S INLAND.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
NEAR SEASONABLE NORMAL TEMPS WILL HIGHLIGHT THE EXTENDED PERIOD
FORECAST. A COLD FRONT WILL BRING SHOWERS TO THE LOCAL AREA ON
TUESDAY.

SRN STREAM ASSOCIATED COASTAL LOW SLOWLY LIFTS NEWD OFF THE MID-
ATLANTIC COAST MON NIGHT-TUES MORNING AS A NRN STREAM SHORTWAVE
DIGS OVER THE GREAT LAKES REGION INTO THE OH VALLEY. ASSOCIATED
COLD FRONT WILL PUSH TOWARD THE LOCAL AREA AS THE PARENT LOW LIFTS
ACROSS NEW ENGLAND. MEDIUM RANGE GUIDANCE IS IN GOOD AGREEMENT
WITH PUSHING THE FRONT THROUGH THE LOCAL AREA TUES AFTERNOON AND
OFF THE COAST TUES EVENING. WHILE THE BEST DYNAMICS WILL BE OVER
THE OH VALLEY AS THE FRONT CROSSES THE LOCAL AREA...A WEAKER
LEADING SHORTWAVE WILL COMBINE WITH INCREASING WINDS ALOFT FOR
AMPLE FORCING FOR ASCENT ALONG THE FRONT. PRECIP WATERS WILL BEGIN
TO RECOVER AS LOW LEVEL H85 FLOW INCREASES. THE RESULT WILL BE
SCATTERED AFTERNOON SHOWERS. THETA-E ADVECTION AND TEMPS IN THE
MID-UPPER 70S WILL ALSO PRODUCE A MARGINALLY UNSTABLE...SO THUNDER
CANNOT BE RULED OUT...ESPECIALLY ACROSS THE SOUTH.
HOWEVER...DEWPOINTS IN THE LOW-MID 50S...LITTLE CAPE/LIFT IN THE
MIXED PHASE LAYER AND MODEST SHEAR WILL LIMIT OVERALL COVERAGE.
HAVE ONLY MENTIONED A SLIGHT CHANCE TUES AFTERNOON FOR THUNDER.
REMNANT MID LEVEL MOISTURE IN NWLY FLOW WILL COINCIDE WITH THE
TROUGH AXIS OVER THE LOCAL AREA TUES NIGHT-WEDS MORNING...AS
ADDITIONAL ENERGY DIVES DOWN THE BACKSIDE OF THE UPPER TROUGH.
THIS WILL LIKELY RESULT IN SOME MID LEVEL CLOUDS WEDS SOME
SPRINKLES POSSIBLE...ESPECIALLY OVER THE NRN LOCAL AREA AND ERN
SHORE. HIGH PRESSURE BUILDS INTO THE REGION WEDS NIGHT-THURS. A
WARM FRONT IS FORECAST TO LIFT OVER THE MID-ATLANTIC REGION THURS
NIGHT-FRI AS A WRN CONUS TROUGH AMPLIFIES AN UPPER RIDGE OVER THE
EAST. FORECAST REMAINS DRY THROUGH THE END OF NEXT WEEK...WITH A
FRONT POSSIBLY IMPACTING THE REGION NEXT WEEKEND.

TEMPS WILL WARM INTO THE MID-UPPER 70S (TO NEAR 80 INLAND) THANKS
TO SLY FLOW IN ADVANCE OF THE APPROACHING COLD FRONT. COOLER WEDS-
THURS BEHIND THE FRONT (NW-W WINDS) WITH HIGHS GENERALLY IN THE
UPPER 60S-LOW 70S. RETURN FLOW ON THE BACKSIDE OF HIGH PRESSURE
LOCATED JUST OFFSHORE WILL WARM TEMPS BACK INTO THE MID-UPPER 70S
FRIDAY. OVERNIGHT LOWS GENERALLY IN THE UPPER 40S-LOW 50S EXCEPT
THURS MORNING WHEN LOWS WILL BE IN THE MID-UPPER 40S.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
WITH NE/ENE FLOW OVER THE AREA...COASTAL SITES MAY EXPERIENCE
ADDITIONAL MVFR CEILINGS FRI NIGHT THROUGH SAT MORNING. IFR
CONDITIONS ARE NOT LIKELY BUT MAY OCCUR AT KECG OVERNIGHT.

STRENGTHENING LOW PRESSURE OVER THE GULF OF MEXICO WILL TRACK ENE
AND INTO THE ATLANTIC OCEAN TROUGH SUNDAY. UPPER LEVEL CLOUDS WILL
BE PRESENT OVER THE FA THROUGH SAT WITH -RA OR SPRINKLES ALSO
ASSOCIATED WITH THE SYSTEM WILL MAKE THERE WAY NORTH OVERNIGHT AND
BEGIN TO EFFECT TAF SITES BY 08Z SAT. KSBY LOOKS TO BE TOO FAR
NORTH TO SEE ANY PRECIP. HIGH PRESSURE BUILDS IN THE THE NW
HELPING TO DRY OUT THE AIRMASS AND ELIMINATE ANY PRECIP CHANCES
SAT EVENING. NE FLOW CONTINUES SAT THOUGH MON AS HIGH PRESSURE
NORTH OF THE AREA MOVES E AND WEDGES SOUTH INTO THE MID-ATLANTIC.

&&

.MARINE...
SFC HIGH PRESSURE REMAINS RIDGED OVER THE WATERS THIS
AFTERNOON...RESULTING IN ONGOING NELY FLOW. SPEEDS GENERALLY 10-15
KT OVER THE BAY AND COASTAL WATERS. SEAS REMAIN
ELEVATED...AVERAGING 5-8 FT. HAVE DROPPED THE SCA FOR THE MOUTH OF
THE BAY AS WAVES HAVE DROPPED BELOW 4 FT AND FOR THE SOUND AS
WINDS HAVE DROPPED BELOW 15 KT. A SFC LOW WILL MOVE ACROSS NRN FL
TODAY...EMERGING OFF THE SE COAST SAT. MEANWHILE...SFC HIGH
PRESSURE WILL BUILD EWD OVER SE CANADA. THE RESULT WILL BE
CONTINUED NE-E FLOW OVER THE WATERS. THE SFC LOW WILL SLOWLY BUILD
NWD THRU THE WEEKEND AND EARLY NEXT WEEK AS HIGH PRESSURE REMAINS
RIDGED OVER THE WATERS. AS A RESULT...NE-E FLOW WILL PERSIST THRU
EARLY NEXT WEEK. SEAS WILL LIKELY REMAIN 4-6 FT THRU MON.
HEADLINES HAVE BEEN EXTENDED THRU THE FOURTH PERIOD (SUNDAY) FOR
ALL COASTAL WATERS. A STRENGTHENING PRESSURE GRADIENT OVER THE SRN
WATERS SAT NIGHT INTO SUN MAY PRODUCE SCA WINDS SPEEDS...BUT IT
WILL DEPEND ON THE LOW TRACK. OTHERWISE...FLOW RETURNS TO THE S
MON NIGHT-TUES IN ADVANCE OF A COLD FRONT. THE FRONT WILL CROSS
THE WATERS TUES AFTERNOON- EVENING. WINDS WILL BACK TO THE NW
BEHIND THE FRONT WITH SCA CONDITIONS POSSIBLE TUES NIGHT-
WEDNESDAY. HIGH PRESSURE RETURNS THROUGH THE END OF THE WEEK.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SUNDAY FOR ANZ650-652-654-
     656-658.

&&

$$
SYNOPSIS...ALB/LSA
NEAR TERM...ALB
SHORT TERM...ALB/LKB
LONG TERM...SAM
AVIATION...DAP
MARINE...SAM






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