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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 142014
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
414 PM EDT FRI MAR 14 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE SOUTHEAST STATES WILL SLIDE OFF THE
CAROLINA COAST TODAY. A WEAK COLD FRONT DROPS THROUGH THE AREA
SATURDAY NIGHT. LOW PRESSURE WILL TRACK FROM THE LOWER
MISSISSIPPI VALLEY NORTHEAST AND OFF THE CAROLINA COAST SUNDAY
THROUGH MONDAY.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
-- Changed Discussion --
A SPECIAL WEATHER STATEMENT REMAINS IN EFFECT THROUGH 6 PM EDT FOR
INCREASED FIRE DANGER ACROSS THE ENTIRE FA DUE TO MIN RH VALUES OF
GENERALLY 15 TO 20 PERCENT AND SUSTAINED WINDS OF 15 TO 20 MPH.
PLEASE REFER TO THE FIRE WEATHER SECTION BELOW FOR MORE DETAILS.

A BROAD SFC HIGH PRESSURE IS LOCATED OFF THE SE COAST LATE THIS
AFTN. THE PLACEMENT OF THE HIGH WILL ALLOW S-SW FLOW TO CONTINUE
OVERNIGHT. A CLIPPER SYSTEM PASSES ACROSS SRN ONTARIO TONIGHT AND
DRAGS A COLD FRONT TWD THE AREA...TIGHTENING THE PRESSURE GRADIENT
AND KEEPING WINDS BREEZY OVERNIGHT. THE FRONT WILL PRIMARILY BE
PRECIP-FREE...HOWEVER THERE IS A VERY REMOTE CHANCE FOR A SPRINKLE
OR TWO ACROSS THE MD LOWER EASTERN SHORE AND OFF THE NE NC COAST
AFTER MIDNIGHT (NO HIGHER THAN 10 PERCENT). OVERALL...THE BEST
LIFT/INSTABILITY IS ELEVATED AND ANY FALLING PRECIP SHOULD
EVAPORATE BEFORE REACHING THE DRY SFC CONDITIONS LEFT IN THE WAKE
OF THE SE COAST SFC HIGH. TEMPS SHOULD GENERALLY FALL INTO THE
LOWER 40S IN THE WELL-MIXED ENVIRONMENT (UPPER 30S FAR WRN AREAS
OF THE FA).
-- End Changed Discussion --

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
-- Changed Discussion --
THE DRY FRONT STALLS ACROSS THE FA BY SAT MORNING AND THEN SLOWLY
SAGS SWD DURING THE DAY. SATURDAY WILL START OUT MOSTLY CLOUDY
WITH SKIES BREAKING UP BY THE AFTN. THE COMBINATION OF SUNSHINE
AND BREEZY WEST WINDS WILL BUMP TEMPERATURES TO READINGS ABOUT 10
DEGREES ABOVE NORMAL. EXPECT HIGHS IN THE MID TO UPPER 60S NORTH
TO UPPER 60S TO LOWER 70S SOUTH.

A COLDER AIRMASS GETS DRAWN INTO THE NE CONUS AS HIGH PRESSURE
BUILDS DOWN FROM CANADA SAT NIGHT. MEANWHILE...A SFC LOW DEVELOPS
OVER THE ARKLATEX REGION SAT NIGHT AND MOVES INTO THE SE STATES ON
SUNDAY. THIS LOW WILL START TO MOVE ALONG THE STALLED BOUNDARY
JUST SOUTH OF THE AREA AND MOVE TWD THE CAROLINA COAST SUN NIGHT
INTO MON. THE AFOREMENTIONED STALLED BOUNDARY IS EXPECTED TO TAKE
ON MORE WARM FRONTAL CHARACTERISTICS SAT NIGHT. AS ISENTROPIC LIFT
AHEAD OF THE CTRL PRESSURE LIFTS OVER THIS BOUNDARY...STEADY RAIN
WILL BEGIN SPREADING INTO THE MID ATLANTIC REGION FROM THE
SOUTHWEST BY SUN MORNING. 12Z MODEL DATA INDICATES THAT A COLD AIR
WEDGE MAY BUILD DOWN THE LEE SIDE OF THE APPALACHIANS SUN NIGHT
INTO MON...WHICH COULD LEAD TO A WINTRY MIX OF PRECIPITATION FOR
NW AND NRN AREAS OF THE FA. HOWEVER...THE CANADIAN HIGH IS PROGGED
TO WEAKEN ON MON...WHICH MAY CAUSE THE COLD AIR TO RETREAT NWD AND
ALLOW THE SFC LOW TO SHIFT NWD ACROSS THE SRN HALF OF THE FA BEFORE
PRECIP-TYPE HAS A CHANCE TO BECOME WINTRY SUN NIGHT INTO MON.
ADDITIONALLY...MODEL SOUNDINGS INDICATE A WARM NOSE DEVELOPING ROUGHLY
BTWN 850-750 MB LATE SUN NIGHT INTO MON MORNING. THERE ARE ENOUGH
DISCREPANCIES BTWN NAM/GFS/SREF SOLUTIONS TO MAKE FOR A TRICKY
FORECAST REGARDING PRECIP-TYPE. TAKING THE CURRENT MODEL DATA INTO
CONSIDERATION...WILL TENTATIVELY LEAN TWD THE COLDER WEDGE
SOLUTION AND CONFINE SLEET OR A RAIN/SLEET MIX TO THE NW HALF OF
THE CWA FOR NOW.

HIGHS SUN IN THE UPPER 40S NW TO LOWER 50S SE. HIGHS MON IN THE
LOW-MID 30S NW TO MID-UPPER 40S SE. LOWS SAT NIGHT IN THE
MID-UPPER 30S MOST AREAS/LOW-MID 40S FAR SE VA/NE NC. LOWS SUN
NIGHT IN THE MID-UPPER 20S NW TO NEAR 40 SE.
-- End Changed Discussion --


&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
-- Changed Discussion --
LOW PRESSURE STEADILY PULLS OFF THE COAST MONDAY NIGHT WITH
PRECIPITATION POTENTIAL DIMINISHING FROM NW-SE. GENERALLY EXPECTING
RA OVER SE PORTIONS...WITH THE POTENTIAL FOR CENTRAL PORTIONS ENDING
AS A MIX OF -SN/IP...AND A SLIGHT CHC OF -SN FOR NRN PORTIONS. HIGH
PRESSURE REMAINS OVER NEW ENGLAND TUESDAY AS LOW PRESSURE LINGERS
OFF THE COAST. NE FLOW SHOULD KEEP HIGH TEMPERATURES BELOW NORMAL
(MID 40S N...TO AROUND 50 S) ALONG WITH ONLY PARTIAL CLEARING.
WEDNESDAY HAS THE POTENTIAL TO BE THE MILDEST DAY AS LOW PRESSURE
PULLS THROUGH THE GREAT LAKES PRODUCING SSW FLOW ACROSS THE REGION.
HOWEVER...THERE IS SOME MOISTURE EMBEDDED WITHIN THE FLOW. THIS
SHOULD KEEP THE SKY PARTLY TO MOSTLY CLOUDY...WITH A SLIGHT CHC POP
ALONG THE COAST. FORECAST HIGHS ARE ABOVE GUIDANCE (DUE TO SSW
LOW-LEVEL FLOW) WITH READINGS RANGING FROM THE UPPER 50S N...TO MID
60S S. A COLD FRONT CROSSES THE AREA WEDNESDAY NIGHT/THURSDAY WITH
LIMITED MOISTURE. DEEP LAYER NW FLOW PREVAILS THEREAFTER FOR THE
REMAINDER OF THE EXTENDED PERIOD.
-- End Changed Discussion --

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
VFR CONDITIONS IN PLACE AT THIS MOMENT AND THESE CONDITIONS SHOULD
PREVAIL THROUGH THE FORECAST PERIOD. WITH HIGH PRESSURE IN
PLACE...JUST OFF THE SE US COAST...STRONG SOUTHWEST FLOW IS
KEEPING DRY AIR IN PLACE...LEADING TO CLEAR SKY. THE SFC HIGH WILL
CONTINUE TO SLIDE EAST TONIGHT IN SATURDAY MORNING...BEFORE A COLD
FRONT...NOW OVER THE CENTRAL PLAINS...SLIDES THROUGH THE REGION.
THIS FRONT LACKS SIGNIFICANT LOW LEVEL MOISTURE...AND SHOULD JUST
PRODUCE SOME MID TO HIGH LEVEL CLOUDINESS UPON ITS PASSAGE EARLY
SAT MORNING. BEHIND THE FRONT THE MOISTURE AGAIN CLEARS AND WITH
WESTERLY FLOW...EXPECT CLEAR SKY INTO SUNDAY.

OUTLOOK: DRY/VFR WX PREVAILS THRU SUNDAY...WITH A CHANCE OF RAIN
BY LATE SUN NGT/MONDAY WITH MVFR TO IFR CONDITIONS POSSIBLE MONDAY
INTO TUESDAY.

&&

.MARINE...
-- Changed Discussion --
HIGH PRESSURE CONTINUES TO SHIFT OFFSHORE THIS EVENING AND OVERNIGHT
AS LOW PRESSURE TRACKS THROUGH THE SAINT LAWRENCE VALLEY. THE
PRESENCE OF A MODEST PRESSURE GRADIENT...ALONG WITH INCREASED MIXING
WITHIN THE NOCTURNAL MARINE BOUNDARY LAYER WILL RESULT IN A PERIOD
OF MARGINAL SCA CONDITIONS...MAINLY OVER THE BAY/NRN OCEAN ZONES. A
SSW WIND OF 15-20KT IS EXPECTED IN THE BAY...WITH A 20-25KT SSW WIND
N OF CAPE CHARLES. SEAS N OF PARRAMORE ISLAND WILL BUILD TO 4-5FT
OUT NEAR 20 NM. EXPECT A 15-20KT SSW WIND OVER THE S OF CAPE CHARLES
WITH ~3FT SEAS. THE SOUND/RIVERS SHOULD EXPERIENCE A 15KT SSW WIND
OVERNIGHT.

THE GRADIENT RELAXES SATURDAY AHEAD OF A COLD FRONT ALONG WITH A
WIND SHIFT TO THE W WITH SPEEDS AOB 15KT. THIS FRONT SAGS THROUGH
THE REGION N-S SATURDAY NIGHT INTO SUNDAY. LOW PRESSURE DEVELOPS
ALONG THE BOUNDARY SUNDAY INTO SUNDAY NIGHT...BEFORE PULLING
OFFSHORE MONDAY. A NE WIND WILL INCREASE SUNDAY AND ESPECIALLY
SUNDAY NIGHT/EARLY MONDAY AS LOW PRESSURE DEEPENS. WIND SPEEDS
POTENTIALLY REACH 25-30KT OVER THE OCEAN/MOUTH OF BAY/SOUND...WITH
20-25KT FOR THE REMAINDER OF THE BAY AND RIVERS. SEAS SHOULD BUILD
TO 6-10FT SUNDAY NIGHT INTO MONDAY. LOW PRESSURE LINGERS OFF THE
COAST THROUGH TUESDAY...AS HIGH PRESSURE REMAINS N OF THE REGION.
THIS WILL RESULT IN CONTINUED ONSHORE FLOW AND SLOWLY SUBSIDING SEAS.
-- End Changed Discussion --

&&

.FIRE WEATHER...
-- Changed Discussion --
A SPECIAL WEATHER STATEMENT REMAINS IN EFFECT THROUGH 6 PM EDT
THIS EVENING FOR INCREASED FIRE DANGER. A MARKEDLY WARMER DAY IS
EXPECTED TODAY...WITH TEMPS WARMING INTO THE UPPER 50S TO
LOWER 60S AND A RELATIVELY DRY S-SW WIND DEVELOPING BY THIS AFTN.
MIN RH VALUES WILL GENERALLY RANGE FROM 15 TO 20 PERCENT ACROSS
THE AREA. 10 HOUR FUELS WILL ALSO CONTINUE TO DRY THROUGH TODAY.
THE MD LOWER EASTERN SHORE MAY BE CLOSE TO REACHING WIND CRITERIA...
HOWEVER MIN RH VALUES ARE ONLY EXPECTED TO FALL INTO THE 20 TO 25
PERCENT RANGE (TOO HIGH TO CONSIDER A RED FLAG WARNING).
-- End Changed Discussion --

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 4 AM EDT
     SATURDAY FOR ANZ631-632-634-654.
     SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR ANZ630.
     SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO NOON EDT
     SATURDAY FOR ANZ650-652.

&&

$$
SYNOPSIS...BMD
NEAR TERM...BMD
SHORT TERM...BMD
LONG TERM...AJZ
AVIATION...ESS
MARINE...AJZ
FIRE WEATHER...BMD