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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 122005
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
405 PM EDT SAT APR 12 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS OFF THE MID ATLANTIC COAST TONIGHT INTO
SUNDAY...AND REMAINS ANCHORED OFF THE COAST THROUGH MONDAY. A SLOW
MOVING COLD FRONT APPROACHES FROM THE WEST MONDAY NIGHT AND
TUESDAY.

&&

.NEAR TERM /THROUGH SUNDAY/...
-- Changed Discussion --
LATEST WX ANALYSIS SHOWING A RATHER DIFFUSE FRONTAL BOUNDARY
EXTENDING NR/JUST SOUTH OF THE VA/NC BORDER EXTENDING SOUTH INTO
NORTH CENTRAL NORTH CAROLINA...AS A ~1025MB SFC HIGH HAS BECOME
CENTERED ALONG THE MID-ATLANTIC/SOUTHEAST COAST. ALOFT, WEAK
SHORTWAVE RIDGING WAS NOTED BUILDING FROM THE SOUTHEAST TOWARDS
THE MID-ATLANTIC REGION. MID-AFTERNOON WV IMAGERY SHOWS A WEAK
DISTURBANCE PUSHING ACROSS THE CENTRAL APPALACHIANS THIS
AFTERNOON, WHICH HAS ALLOWED SOME SCT CU TO POP UP ACROSS THE
PIEDMONT.

OLD SURFACE BOUNDARY IS DIFFICULT TO DISCERN ANYMORE, APART FROM A
BROAD WIND FIELD SHIFT JUST SOUTH OF THE LOCAL AREA. SURFACE HIGH
PRESSURE STRENGTHENS OFF THE MID ATLANTIC COAST TONIGHT INTO
SUNDAY, IN RESPONSE TO A BUILDING MID/UPPER RIDGE OVER THE WESTERN
ATLANTIC. ACCORDINGLY, WINDS ACROSS THE REGION WILL SHIFT TO THE
S-SE THIS EVENING, VEERING AROUND TO THE SW LATE TONIGHT. THIS
SHOULD ALLOW AN INCREASE IN LOW LEVEL MOISTURE AND SOME PATCHY
STRATUS DEVELOPING OVERNIGHT, WHICH WILL BRING MILD EARLY MORNING
LOWS SUNDAY. IT WILL ALSO SERVE TO BOOST HIGHS SUNDAY BACK INTO
THE UPPER 70S/LOW 80S AWAY FROM THE COASTLINES. ANY MORNING
STRATUS WILL GIVE WAY TO A MOSTLY SUNNY SKY BY SUNDAY MORNING.
HIGHS SUNDAY WILL BE LOCALLY COOLER ALONG THE COASTS...ESPECIALLY
THE ATLANTIC COAST OF THE EASTERN SHORE WHERE MAXIMA MAY ONLY HOLD
IN THE LOW/MID 60S.
-- End Changed Discussion --

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...

-- Changed Discussion --
NO MAJOR CHANGE IN FORECAST RATIONALE FOR THE FIRST HALF OF THE
WEEK AHEAD. OVERALL, A DEEP UPPER LEVEL TROUGH WILL PUSH A STRONG
COLD FRONT THROUGH THE OHIO VALLEY MONDAY/MONDAY NIGHT, WITH A
SECOND TRAILING SHORTWAVE PUSHING FROM THE TEXARKANA REGION ACROSS
THE SOUTHEAST TUESDAY THROUGH TUESDAY NIGHT. FORECAST REMAINS DRY
SUNDAY NIGHT THROUGH MONDAY NIGHT, AS THERE IS PLENTY OF MID-
LEVEL DRY AIR ASSOCIATED WITH THE WESTERN ATLANTIC RIDGE. INCREASE
TO HIGH LIKELY TO CATEGORICAL POPS (70-80%) LATE MONDAY
NIGHT/EARLY TUESDAY MORNING ACROSS THE PIEDMONT/CENTRAL VA ZONES
AS FRONT APPROACHES FROM THE WEST. RAIN WILL LIKELY BEGIN AS SOME
LIGHTER SHRAS AS SHALLOW LIFT ENSUES AHEAD OF THE FRONT MONDAY
NIGHT...WITH MORE STEADY RAINFALL EXPECTED AFTER MIDNIGHT INTO
TUESDAY MORNING, AS PW VALUES QUICKLY RAMP UP THROUGH TUESDAY AS
MID- UPPER TROUGH TAPS INTO GULF MOISTURE. DELAYED RAMPING UP
POPS ACROSS THE EAST AS FORCING REMAINS MEAGER AT BEST UNTIL
TUESDAY THROUGH TUESDAY NIGHT.

REGARDING THUNDERSTORM CHANCES...DID RETAIN SOME THUNDER WORDING
ON TUESDAY AFTN/EVENING AS FRONT PUSHES ACROSS THE AREA AND LOW
PRESSURE SLIDES ALONG THE BOUNDARY. MODELED CAPE VALUES ARE MEAGER
AT BEST, WHICH MAKES SENSE GIVEN CONSIDERABLE CLOUD COVER.
HOWEVER, WITH CONSIDERABLE DEEP LYR BULK SHEAR AND THE POTENTIAL
FOR A FORCED LINE OF CONVECTION, SOME THUNDERSTORMS ARE POSSIBLE,
ESPECIALLY ACROSS THE SOUTHERN HALF OF THE AREA. OVERALL THOUGH,
PRIMARY THREAT WILL JUST BE WITH A BRIEF WINDOW OF MODERATE TO
HEAVY RAINFALL TUESDAY AND TUESDAY NIGHT.

FOR TEMPERATURES...HIGHS MONDAY SHOULD BE IN THE MID/UPPER 70S
(LOCALLY COOLER ALONG THE COASTS) UNDER A PARTLY SUNNY SKY.
INCREASING CLOUDS AND MILD SW FLOW WILL KEEP LOWS IN THE LOWER TO
MIDDLE 60S MONDAY NIGHT...WITH HIGHS IN THE 60S WEST TO LOW 70S
EAST ON TUESDAY.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
-- Changed Discussion --
LONG TERM PERIOD STARTS OFF TUE NGT WITH AFOREMENTIONED LO PRES AND
ASSOCIATED COLD FRONT PUSHING OFFSHORE. 12Z ECMWF HAS COME IN LINE
WITH THE 12Z GFS WITH ENDING THE PRECIP OVR THE AREA BY WED MORN.
WILL RETAIN CHANCE POPS FOR WED HOWEVER WITH THIS STILL SEVERAL
DAYS OUT AND STILL SOME UNCERTAINTY WITH HOW FAST THIS SYSTEM MOVES
OFFSHORE. DRYING CONDITIONS WILL FOLLOW...WITH A PROLONGED PERIOD OF
PARTLY/MOSTLY CLOUDY SKIES AND ONSHORE FLOW AS SFC HI PRES STRADDLES
THE MID ATLANTIC CST. AS FOR TEMPS...READINGS WILL AVG BLO NORMAL
FOR THE PERIOD...WITH HIGHS IN THE 50S AND 60S. TEMPS TUE NGT AND
WED NGT WILL FALL INTO THE MID/UPR 30S OVR THE PIEDMONT...BRINGING
THE POTENTIAL FOR FROST THERE.
-- End Changed Discussion --

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD WITH ONLY A FEW
SCATTERED CLOUDS EXPECTED. HIGH PRESSURE MOVES OVER THE REGION
AND OFF THE MID ATLANTIC COAST TONIGHT. WINDS WILL GRADUALLY
SHIFT FROM NE-SE-S THRU THE PERIOD. THE FRONT THAT MOVED THRU
EARLY THIS MORNING WILL RETURN AS A WARM FRONT TONIGHT. SOME
PATCHY FOG AND STRATUS WILL BE PSBL OVERNIGHT AS THE FRONT MOVES
NORTH BUT IS NOT EXPECTED TO BE WIDESPREAD.

A COLD FRONT APPROACHES THE REGION ON MONDAY. THE FRONT WILL
BRING WIDESPREAD PRECIP TO THE REGION MON NIGHT INTO WED.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
BENIGN MARINE CONDITIONS TNGT AS A WEAK FRONT WASHES OUT SOUTH OF THE
AREA AND SFC HI PRES ANCHORS OFFSHORE. THE HI WILL REMAIN IN PLACE
FOR THE NEXT COUPLE DAYS LEADING TO CONTINUOUS SLY FLOW. EXPECT 5-10
KT WINDS TNGT WITH 1-2 FT WAVES OVR THE BAY AND 2-3 FT SEAS OVR CSTL
WTRS. FOR SUN...WINDS OVR THE BAY WILL INCREASE TO 15 KT IN THE
AFTN...POSSIBLY UP NEAR 20 KT IN THE LATE AFTN AND EVENING...WITH SEAS
OVR NRN CSTL WTRS POSSIBLY REACHING 4-5 FT AS WELL. CONFIDENCE AT THIS
POINT IS NOT HI ENOUGH TO ISSUE A LATE 2ND/3RD PERIOD SCA. SCA
CONDITIONS ARE MORE LIKELY LATE MON THRU AT LEAST THE MIDDLE OF THE
WEEK AS A COLD FRONT APPROACHES THE WTRS AND CROSSES BY TUE EVENING.
PROLONGED NE FLOW THEREAFTER WILL KEEP SEAS ELEVATED AOA 5 FT THRU
THE END OF THE WEEK.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...AJZ/MAM
LONG TERM...LKB
AVIATION...JEF
MARINE...SAM