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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 120201
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
1001 PM EDT TUE MAR 11 2014

.SYNOPSIS...
HIGH PRESSURE WILL SLIDE OFF THE SOUTHEAST COAST THROUGH
TONIGHT...AS A COLD FRONT APPROACHES FROM THE WEST. THE FRONT WILL
CROSS THE REGION LATE WEDNESDAY INTO WEDNESDAY NIGHT. HIGH
PRESSURE RETURNS THURSDAY AND FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
-- Changed Discussion --
CLEAR SKIES...DEWPOINTS IN THE MID-UPPER 30S AND LIGHT WINDS
ALLOWED FOR EXCELLENT RADIATIONAL COOLING THIS EVENING OVER THE
LOCAL AREA. MOST LOCALES FELL MORE THAN 10 DEGS IN AN HOUR FROM
7-8PM. FOR EXAMPLE...WAKEFIELD DROPPED 14 DEGS DURING THAT
TIME FRAME. COOLING TREND WILL SLOW AS CLOUDS INCREASE FROM THE SW
AND LIGHT SLY FLOW CONTINUES. BUMPED UP TEMPS A DEG OR
TWO...GENERALLY IN THE LOW 50S. THE EXCEPTION WILL BE THE ERN
SHORE WITH TEMPS FALLING INTO THE LOW-MID 40S.

CLOUDS WILL INCREASE FROM THE SW AS A SRN STREAM SHORTWAVE
DE-AMPLIFIES AND PROGRESSES EWD OVER THE GULF STATES. STRONGER NRN
STREAM SHORTWAVE ENERGY AND ASSOCIATED SFC LOW AND COLD FRONT WILL
APPROACH FROM THE WEST TONIGHT. NEAR TERM WILL REMAIN DRY AS
MEASURABLE PRECIP WILL REMAIN WEST OF THE LOCAL AREA.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
THAT LO WILL INTENSIFY AS IT MOVES NE TO JUST OFF THE NEW ENGLAND
CST WED INTO WED NGT. MODELS (12Z GFS/NAM/ECMWF) IN GENERAL
AGREEMENT WITH TIMING/MOVEMENT/LOCATION OF SFC LO PRES AND COLD
FRONT PUSHING THRU THE NE U.S. AND MID ATLC REGION. THE NAM IS A
BIT SLOWER THAN THE OTHER TWO MODELS WITH THE COLD FRONT PASSAGE.
MODELS DO AGREE THAT AN INITIAL AREA OF SHOWERS WILL SPREAD ACRS
THE CWA FM ARND 10 AM TO 5 PM WED...THEN A LINE OF SHOWERS AND
POSSIBLY A FEW TSTMS RIGHT AHEAD OF THE COLD FRONT WILL PUSH EWRD
AND OFF THE CST FM ARND 5 PM TO 10 PM WED EVENG. SW WINDS WILL
BECOME BREEZY/WINDY FM MIDDAY WED INTO WED EVENG (GUSTS TO 25-35
MPH)...HELPING TO BOOST TEMPS INTO THE LWR TO MID 70S OVR MOST OF
THE AREA.

THE COMBINATION OF INTENSIFYING LO PRES MOVNG BY JUST TO THE N OF
THE REGION...MARGINAL INSTABILITY...AND FAVORABLE WIND
PROFILES...COULD RESULT IN A FEW STRONG OR SEVERE TSTMS WITH
DAMAGING WINDS THE MAIN THREAT. SO FAR...THE SPC HAS MOST OF CNTRL
AND SCNTRL VA AND THE LWR MD ERN SHR IN A SLGT RISK FOR WED. THE
LINE OF SHOWERS OR STORMS AND THE COLD FRONT WILL MOVE OFF THE
CST WED EVENG. RAINFALL AMTS FOR THIS EVENT EXPECTED TO BE .25
INCH OR LESS...WITH LOCALLY HIGHER AMTS POSSIBLE IN ANY HEAVIER
SHOWERS OR STRONGER TSTMS.

WED NGT THRU THU...VERY STRONG NW WINDS WILL USHER A MUCH DRIER
AND COLDER AIRMASS INTO THE REGION (POTENTIAL GUSTS TO 40-45
MPH...ESPLY ERN/NE PORTIONS). BECOMING CLEAR TO PARTLY CLOUDY WED
NGT WITH LOWS RANGING FM THE MID 20S TO MID 30S. SUNNY/MOSTLY
SUNNY AND NOTICEABLY COLDER ON THU WITH HI TEMPS ONLY RANGING FM
THE UPR 30S TO MID 40S.

HI PRES THEN BLDS OVR THE AREA THEN SLIDES OUT TO SEA THU NGT AND
FRI. CLEAR/MOSTLY CLEAR AND COLD THU NGT WITH MIN TEMPS RANGING FM
THE UPR TEENS TO MID 20S. MOSTLY SUNNY AND A BIT BETTER AGAIN ON
FRI WITH HIGHS RANGING FM THE UPR 40S TO UPR 50S.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
NOT EXPECTING A PROLONGED PERIOD OF COLD TEMPS AS HIGH PRESSURE THAT
BUILDS IN FROM THE WEST QUICKLY MOVES EAST AND A RETURN FLOW RESULTS
HELPING TO PUSH A WARMER AIRMASS BACK INTO THE AREA FRIDAY EVENING.

FLOW REMAINS OUT OF THE SW ON SAT AS MODELS INDICATE CONVERGENCE
ALONG A SURFACE TROUGH MAY PRODUCE A LINE OF LIGHT SHOWERS ON SAT.
DUE TO MODEL DIFFERENCES...CONFIDENCE IS NOT HIGH ENOUGH TO ADD WX
INTO THE FORECAST AT THIS POINT. HIGH PRESSURE CENTERED NORTH OF THE
GREAT LAKES BEGINS TO NOSE DOWN INTO THE MID-ATLANTIC SAT NIGHT
AHEAD OF THE NEXT APPROACHING SURFACE LOW THAT WILL BE FORMING IN
THE SE US AND MOVING NE ON MONDAY. CHANCES FOR PRECIPITATION
INCREASE SUN NIGHT INTO MONDAY WITH THE APPROACH OF THAT LOW
PRESSURE SYSTEM. NW SURFACE FLOW/CLOUDS/PRECIP WILL CREATE COOL
CONDITIONS SUN THROUGH TUE.

EXPECT TEMPS IN THE MID 60S FOR SAT...FALLING INTO THE MID 50S FOR
SUNDAY AND INTO THE LOW 50S/UPR 40S ON MON. COOL/NEAR SEASONAL
MORNING TEMPS IN THE 30S EXPECTED THROUGH THE WEEKEND.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
A CLEAR SKY COVERED THE TAF SITES EARLY TUESDAY EVENING. WINDS WILL
REMAIN LIGHT OVERNIGHT.

LOW PRESSURE ORGANIZES OVER THE OHIO VALLEY AND INTENSIFIES AS IT
MOVES INTO NORTHERN PORTIONS OF THE MIDDLE ATLANTIC STATES.
SOUTHWEST WINDS WILL GUST TO AROUND 30 KNOTS WEDNESDAY. A VERY
DYNAMIC SYSTEM AND ASSOCIATED COLD FRONT WILL IMPACT THE REGION LATE
WEDNESDAY. THERE WILL BE A CHANCE FOR TSTMS DURING THE AFTN AND
EVENING WITH STRONG TO SEVERE WIND GUSTS PSBL. FOR NOW...INCLUDED
SHRA AT RIC SBY AND PHF IN THE AFTN. IFR CONDS ARE ONLY EXPECTED
WITH HEAVIER PCPN.

SKIES CLEAR WEDNESDAY NIGHT. NW WINDS MAY GUST TO OVER 30 MPH
THURSDAY AND NEAR 40 MPH AT SBY. DRY/VFR WEATHER PREVAILS THURSDAY
THROUGH SUNDAY. A COLD FRONT MOVES THROUGH SATURDAY. THERE WILL BE A
CHANCE OF RAIN BY MONDAY.

&&

.MARINE...
GALE WARNINGS RAISED FOR THE BAY AND COASTAL WATERS WITH THE
APPROACH OF LOW PRESSURE SYSTEM AND STRONG COLD AIR ADVECTION BEHIND
THE SYSTEM. SCA CONDITIONS WILL PRECEDE GALE CONDITIONS OVER THE
WATERS BY 8-10 HRS BUT HAVE COVERED THE PERIOD WITH A GALE WARNING
TO AVOID TWO HEADLINES. INITIAL GALE AND SCA SET THROUGH 00Z FRI.
SCA WILL COVER THE RIVERS AND CURRITUCK SOUND...BUT FAVORABLE NW
WIND DIRECTION MAY BE ABLE TO PUSH GUSTS TO NEAR GALE CRITERIA OVER
THOSE AREAS.

CONDITIONS OVER THE WATERS REMAIN BENIGN THROUGH WED MORNING. AT
THIS TIME A STRENGTHENING LOW PRESSURE SYSTEM MOVING INTO THE OHIO
RIVER VALLEY WILL HELP TO INCREASE THE PRESSURE GRADIENT OVER THE
MID-ATLANTIC. STRENGTHENING SW WINDS WILL OCCUR ON WED BUT DUE TO
THE WARM AIRMASS MOVING OVER THE COLDER WATERS...MIXING OF THE
STRONGEST WINDS TO THE WATERS SURFACE WILL BE DIFFICULT. WITH THAT
SAID...SMALL CRAFT CONDITIONS WILL BE LIKELY AHEAD OF THE SYSTEM
WED AFTN INTO WED EVENING. AT THIS POINT THE SYSTEM AND ASSOCIATED
COLD FRONT WILL HAVE MADE ITS WAY ACROSS THE WATERS AND
SIGNIFICANT PRESSURE RISES AND COLD AIR ADVECTION WILL TAKE PLACE.
THESE FACTORS WILL SET THE STAGE FOR THE GALE EVENT. A LINE OF
STRONG TO SEVERE STORMS MAY ALSO BE A POSSIBILTY ON WED AFTN DUE
TO STRONG LOW LEVEL WINDS AND WARMING ENVIRONMENT.

EXPECT WAVES TO INCREASE OVER THE BAY FROM 3 FT ON WED AFTN TO
AROUND 5 FT BY THU MORNING AS THE STRONG NW WINDS MOVE IN. SEAS
APPROACHING 10 FT AT 20 NM OUT WILL BE POSSIBLE BY THU AFTN...WITH 3
TO 5 FT SEAS LIKELY CLOSER TO SHORE. CONDITIONS RELAX BY THU NIGHT
AS HIGH PRESSURE BEGINS TO MAKE ITS WAY INTO THE AREA.

PRESSURE GRADIENT INCREASES ONCE AGAIN FRIDAY EVENING BETWEEN HIGH
PRESSURE TO OUR SOUTH AND LOW PRESSURE SYSTEM MOVING NORTH OF THE
GREAT LAKES. A SURGE OVER THE WATERS IS EXPECTED DURING THAT TIME.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM WEDNESDAY TO 8 PM EDT THURSDAY
     FOR ANZ633-635>638.
     GALE WARNING FROM 1 PM WEDNESDAY TO 8 PM EDT THURSDAY FOR
     ANZ630>632-634-650-652-654-656-658.

&&

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