Area Forecast Discussion
Issued by NWS Wakefield, VA

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000
FXUS61 KAKQ 311713
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
113 PM EDT FRI OCT 31 2014

.SYNOPSIS...
WEAK HIGH PRESSURE BUILDS ACROSS THE AREA TODAY. A STRONG LOW
PRESSURE SYSTEM WILL DEVELOP OFF THE MID ATLANTIC COAST SATURDAY
AND SATURDAY NIGHT BEFORE EXITING THE AREA ON SUNDAY. HIGH
PRESSURE RETURNS FOR THE BEGINNING OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
QUICK UPDATE TO FCST TO INCRS CLDNS THIS MRNG ACRS CNTRL/ERN
PORTIONS OF FA.

PREV DISCUSSION...
MID-MRNG SFC ANALYSIS SHOWS VERY WK HI PRES INVOF CNTRL MTNS...W/
A LINGERING FNTL BNDRY OFF THE CST...AND A PROGRESSIVE BAROCLINIC
WAVE TRACKING ALONG THE BNDRY. ALSO...ONE S/W ALOFT MOVING
THROUGH THE LWR OH VLY...AND A 2ND (STRONGER) ONE DIVING SE
THROUGH THE WRN LAKES STATES.

TDA BEGINS COOL AND MCLDY (W/ EXCEPTION OF THE FAR SW
PIEDMONT)...WITH A CLEARING LINE TRACKING FROM SSW-NNE AS THE LOW
PULLS FARTHER NE. INITIAL S/W CARVES OUT TROUGH INTO INTERIOR SE
CONUS STATES AND AWAITS ARRIVAL OF THE 2ND S/W FM THE NNW. VERY WK
SFC HI PRES RMNS IN PLACE LONG ENOUGH FOR A MNLY DRY DAY ACRS THE
FA. COMBO OF SYS E AND W OF THE FA WILL RESULT IN VRB CLDS TO
PCLDY CONDS MOST PLACES THIS AFTN. WILL HAVE SLGT CHC TO LO END
CHC POPS RIGHT ALG THE IMMEDIATE CST IN SE VA/NE NC THIS AFTN AS
THE SFC LO TRACKS OFF THE CST. HI TEMPS FM THE U50S NNW TO 60 TO
65F ELSW.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
STRONG S/W WILL CONTINUE TO DIG SOUTH FROM THE TN VALLEY ACROSS
THE DEEP SOUTH TNGT...THEN THROUGH THE CAROLINAS ON SAT. CONTD
GOOD MODEL AGREEMENT DEPICTING UPPER LOW CLOSING OFF OVER THE
CAROLINAS MIDDAY SAT. MODELS CONTINUE TO SPIN-UP SECONDARY
CYCLOGENESIS OFFSHORE OF THE NC COAST SAT AFTN/EVE...BEFORE
QUICKLY EJECTING NORTHEAST AWAY FROM THE AREA LATE SAT NGT INTO
SUNDAY MORNING. COOL 1030+MB HIGH PRESSURE WILL SETTLE EAST FROM
THE MISSISSIPPI VALLEY LATE SATURDAY THROUGH MONDAY.

00Z/31 SUITE OF MODELS RMN IN GOOD AGREEMENT THAT RAIN WILL
INCREASE IN COVERAGE LATE TNGT THROUGH SATURDAY. BREEZY OVERALL
ON SATURDAY...WITH BEST SURGE OF CAA LIKELY HOLDING OFF UNTIL SAT
NGT. GIVEN FCST OF HOW FAR S UPR LVL SYS TRACKS...MOST SIGNIFICANT
IMPACTS (BOTH WND AND RA) APR TO BE OVER FOR ERN/SERN CSTL
LOCATIONS (PRIMARILY) FM MIDDAY SAT INTO EARLY SAT EVENING.
ADDITIONALLY, A PERIOD OF STRONG NNE WNDS (35-45 MPH) EXPECTED
ALONG COASTAL ZONES W/AREAS OF MINOR TIDAL FLOODING ALONG THE ATLC
BEACHES AND LWR CHES BAY (SEE COASTAL FLOODING SECTION BLO). WILL
CONT TO HIGHLIGHT POTENTIAL IMPACTS IN HWO. A WIND ADVISORY MAY BE
NEEDED OVER AT LEAST SOME OF OUR COASTAL ZONES SAT NGT FOR A 6-10
HOUR PERIOD IF CURRENT FORECAST RATIONALE PANS OUT.

PCPN WILL TAPER OFF SAT NGT W/ SUBSIDENCE IN THE WAKE OF THE
DEPARTING WAVE...AND SKY CLEARS OUT QUICKLY INTO SUNDAY MORNING AS
SURFACE HIGH OF CANADIAN ORIGIN SINKS FROM THE OHIO VALLEY INTO
THE SOUTHEAST BEGINNING SUNDAY. THIS WILL USHER IN THE COOLEST AIR
OF THE SEASON TO DATE.

WRT QPF...MOST INLAND PLACES MAY HAVE AVG AMOUNTS LESS THAN 0.25
IN...W/ HIGHER AMOUNTS (TO 0.50 TO PSBLY 0.75 IN) MNLY CONFINED TO
CLOSE TO THE CST.

FOR TEMPERATURES...WIDESPREAD CLOUDS AND INCREASING RAIN CHCS
WILL KEEP HIGHS IN THE 50S FOR MOST ON SATURDAY...THOUGH TEMPS MAY
NOT MAKE IT OUT OF THE 40S WELL INLAND. WELL MIXED ATMOS/BREEZY-
WINDY CONDS WILL KEEP TEMPS FROM BOTTOMING OUT SATURDAY
NIGHT...BUT STILL CHILLY WITH LO TEMPS IN THE MID 30S INLAND TO
LOW 40S ALONG THE COAST. DESPITE A MOSTLY SUNNY SKY...ONGOING LO
LVL CAA WILL KEEP HIGHS SUNDAY IN THE 50S...OR ROUGHLY -1 TO -1.5
STD DEV FROM CLIMO.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
STRONG HIGH PRESSURE SETTLES OVER THE MID ATLANTIC SUNDAY NIGHT. BY
MONDAY MORNING LOWS SHOULD FALL TO AROUND 30-32 FOR MUCH OF THE
AREA (UPPER 20S POSSIBLE IN FAVORED COLD SPOTS)...WITH SLIGHTLY
HIGHER VALUES (35-40) FOR FAR SE PORTIONS. THIS HAS THE POTENTIAL TO
PRODUCE THE FIRST WIDESPREAD FREEZING TEMPERATURES THIS FALL ACROSS
THE LOCAL AREA. A SLOW MODERATING TREND IS EXPECTED MONDAY THROUGH
WEDNESDAY AS THE HIGH GRADUALLY MOVES OFFSHORE. HIGHS MONDAY SHOULD
RANGE FROM 55-60...WITH MID/UPPER 60S POSSIBLE BY TUESDAY AND
WEDNESDAY. OVERNIGHT LOWS SHOULD REMAIN RATHER COOL TUESDAY MORNING
RANGING FROM THE LOW/MID 30S INTERIOR TO LOW 40S FOR SE COASTAL
LOCATIONS. LOWS SHOULD MODERATE INTO THE MID 40S/LOW 50S WEDNESDAY
MORNING WITH THE HIGH WELL OFFSHORE AND THE RESUMPTION OF SSW FLOW.
THE NEXT COLD FRONT APPROACHES FROM THE NW WEDNESDAY/WEDNESDAY
NIGHT...AND TRACKS THROUGH THE MID ATLANTIC WEDNESDAY
NIGHT/THURSDAY. AT THIS TIME MOISTURE APPEARS RATHER LIMITED WITH
THIS FRONT...SO ONLY SLIGHT CHC POPS ARE INCLUDED AT THE END OF THE
FORECAST PERIOD.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
MAINLY VFR CONDITIONS WILL PREVAIL TODAY AS A WEAK AREA OF HIGH
PRESSURE PERSISTS OVER THE AREA. THE HIGH DISSIPATES OVER THE
REGION THIS AFTN WHILE SETTING UP A WEAK WEDGE THAT...DUE TO THE
RESULTING NE FLOW...MAY CAUSE SOME MVFR CEILINGS TO OCCUR AT
KORF/KPHF/KECG THIS AFTERNOON AND EVENING. ALSO TODAY...A WEAK
AREA OF LOW PRESSURE WILL DEVELOP ALONG A STALLED FRONTAL BOUNDARY
OFF THE CAROLINA COAST. INCREASING MOISTURE ALONG WITH A FEW
SHOWERS MAY IMPACT THE NE NC/SE VA COAST...BUT RAIN CHANCES ARE
TOO LOW ATTM TO INCLUDE MENTION IN THE TAFS.

STRONG UPPER LEVEL SYSTEM WILL MOVE ACROSS THE OH AND THEN TN
RIVER VALLEYS INTO SAT. THIS SYSTEM WILL HELP FORM A STRONG
COASTAL SYSTEM OFF THE OUTER BANKS LATE SAT INTO SUN. AS THIS
SYSTEM DEEPENS AND MOVES OFF THE COAST...20-30 KT N WINDS WITH
HIGHER GUSTS WILL BE POSSIBLE FROM SAT NIGHT THROUGH SUN AFTN.

&&

.MARINE...
QUICK UPDATE TO HOIST SHORT DURATION SCA OVER THE CURRITUCK SOUND.
SURFACE LOW PRESSURE HAS DEVELOPED ALONG THE STALLED COASTAL FRONT
OFFSHORE. EXPECT WINDS TO INCREASE TO LOW END/MARGINAL SCA
CRITERIA THIS AFTN AND EARLY THIS EVENING BEFORE DIMINISHING
TONIGHT AS SYSTEM LIFTS NE WELL OFFSHORE OF NEW ENGLAND COAST BY
LATE TONIGHT. WINDS BRIEFLY DIMINISH AND BACK TO THE NNW TONIGHT,
BEFORE RAMPING UP AGAIN TOWARDS SUNRISE SAT MORNING, AS LOW
PRESSURE DEVELOPS NEAR KHAT. WINDS/WAVES/SEAS INCREASE AS THIS
LOW PRES STRENGTHENS OFF THE NC CST IN RESPONSE TO A VERY POTENT
MID- LEVEL SHORTWAVE TROF. SCA OVR NRN CSTL WTRS REMAINS IN EFFECT
FOR SATURDAY BEFORE THE GALE WARNING GOES INTO EFFECT SATURDAY
NIGHT. A PERIOD OF 5 FT SEAS IS EXPECTED OVER NORTHERN WATERS, WHILE
CONDITIONS ELSEWHERE RAMP UP FAST ENUF TO JUST WARRANT A GALE
HEADLINE. CONDITIONS OVR THE RIVERS OTHER THAN THE LWR JAMES ARE
EXPECTED TO STAY SUB- GALE SO A SCA HAS BEEN ISSUED THERE. BRIEF
WINDS CLOSE TO STORM FORCE ARE PSBL OVR SRN CSTL WTRS...BUT WITH
THE SPEED AND TRACK OF THE SFC LO...EXPECT WINDS TO STAY MAINLY IN
THE GALE RANGE. STRONGEST WINDS OVR THE BAY/SOUND/CSTL WTRS (30-40
KT SUSTAINED WITH GUSTS TO 40-45 KT) WILL OCCUR SAT NGT...AND
SLOWLY DIMINISH ON SUN AS THE LO PULLS WELL NE OF THE AREA. EXPECT
4-6 FT WAVES OVR THE BAY AND SEAS OVR CSTL WTRS UP TO 10-12 FT. HI
PRES BLDS OVR THE AREA SUN NGT AND MON AND THEN SLOWLY MOVES
OFFSHORE ERLY TO MID NEXT WEEK...WITH SUB-SCA CONDITIONS EXPECTED.

&&

.TIDES/COASTAL FLOODING...
LOW PRESSURE IS EXPECTED TO RAPIDLY STRENGTHEN OFF THE COAST LATE
SATURDAY AFTERNOON AND SATURDAY NIGHT. TIDAL DEPARTURES OF 1-1.5 FT
ABOVE NORMAL ARE POSSIBLE SATURDAY NIGHT ALONG THE ATLANTIC COAST
AND LOWER BAY. MINOR TIDAL FLOODING IS EXPECTED FOR THESE LOCATIONS
IF THE SURGE COINCIDES WITH THE HIGH TIDE CYCLE SATURDAY NIGHT.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM EDT SATURDAY TO 4 PM EST SUNDAY
     FOR ANZ635>637.
     GALE WARNING FROM 4 PM EDT SATURDAY TO 7 AM EST SUNDAY FOR
     ANZ630>634-638.
     SMALL CRAFT ADVISORY UNTIL 1 AM EDT SATURDAY FOR ANZ633.
     GALE WARNING FROM 4 PM EDT SATURDAY TO 10 AM EST SUNDAY FOR
     ANZ650-652-654-656-658.
     SMALL CRAFT ADVISORY FROM 7 AM TO 4 PM EDT SATURDAY FOR ANZ650-
     652.

&&

$$
SYNOPSIS...ALB/MAM
NEAR TERM...AJZ/ALB
SHORT TERM...ALB
LONG TERM...AJZ
AVIATION...MAS
MARINE...MAS/MAM
TIDES/COASTAL FLOODING...






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