Area Forecast Discussion
Issued by NWS Sterling, VA

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000
FXUS61 KLWX 301937
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
337 PM EDT MON MAR 30 2015

.SYNOPSIS...
DRY NORTHWEST WINDS WILL CONTINUE BEHIND A COLD FRONT INTO THE
LATE EVENING HOURS...WHILE ANOTHER POTENT UPPER LEVEL LOW QUICKLY
APPROACHES FROM THE GREAT LAKES REGION. THIS FEATURE WILL MOVE
ACROSS THE REGION ON TUESDAY...REINFORCING THE DRY AND WINDY
CONDITIONS. HIGH PRESSURE WILL BRIEFLY BUILD IN DURING THE MIDDLE
OF THE WEEK...WITH ANOTHER COLD FRONT EXPECTED BY THE END OF THE
WORK WEEK.

&&

.NEAR TERM /THROUGH TUESDAY/...
A COMPLEX UPPER LEVEL TROUGH NOW MOVING OFF THE COAST AND BEHIND
THE EXITING COLD FRONT...WNW BREEZES IN THE 20-30KT RANGE CONTINUE
THRU THE LATE AFTN HRS. MAX TEMPS W/ THE CLEARING SKIES WILL PEAK
IN THE 50S AND L60S. CONDITIONS WILL QUIET DOWN OVERNIGHT W/ CLEAR
SKIES AND LIGHT WINDS. LOWS WILL DROP BACK INTO THE 30S FROM THE
DRIER AIRMASS THAT HAS BEEN OVERCOMING THE AREA IN RECENT HRS.

AN INITIALLY WEAK AND MINOR UPPER WAVE OVER THE WRN GREAT
LAKES/NRN PLAINS WILL BECOME A POTENT AND TIGHTLY- WOUND VORT LOBE
THAT WILL SLIDE DIRECTLY OVER THE MID-ATLC REGION ON TUE. MUCH OF
THE PRECIP AND GUSTY WINDS WILL BE TIGHTLY PACKED NEAR THE SFC
FEATURE. STARTING OFF THE DAY...IT WILL SEEM PRETTY CALM ACROSS
THE REGION W/ SOME MID CLOUD DECKS COMING IN FROM THE NW. TOWARD
THE MID MRNG HRS...WINDS WILL KICK UP OUT OF THE SW AND QUICKLY
START TO GUST IN THE 20-30KT RANGE...W/ HIGHER GUSTS OVER THE
TERRAIN OF THE SW/BLUE RIDGE MTNS.

LOOKING THRU SOME OF THE HI-RES MODELS IN THE NEAR TERM...THE
PRECIP W/ THE DEVELOPING SYSTEM TMRW WILL BE CLOSE TO THE LOW
WHICH LOOKS TO TRACK ACROSS THE MASON-DIXON LINE. THE HIGHEST
EXPECTED QPF IS ACROSS NRN/NE MD...AND THE HEAVIEST ALONG W/ THE
EVENTUAL COLD FRONT LATE AFTN/EVE TIME. DENSE OVERCAST ASSOCIATED
W/ THIS ACTIVITY NEAR THE SFC LOW OVER THE NRN HALF OF THE CWA BUT
SKIES WILL BE LESS CLOUDY OVER THE SWRN ZONES AND WINDS WILL GUST
OUT OF THE SW...BUILDING THE FIRE WX CONCERNS FOR THE AREAS
SURROUNDING THE BLUE RIDGE/FOOTHILLS AND SHEN VLY. SEE FIRE WX
SECTION BELOW.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
FAST-MOVING CLIPPER SYSTEM WILL MOVE AWAY FROM THE MIDDLE ATLANTIC
REGION TUESDAY NIGHT. A COOLER AIRMASS WILL BUILD IN BEHIND THE
LOW PRESSURE SYSTEM AND TEMPERATURES WILL FALL BACK INTO THE 30S
IN MOST LOCALES WITH 20S OVER THE WEST. NORTHWEST WINDS WILL ALSO
GRADUALLY DIMINISH OVERNIGHT.

HIGH PRESSURE WILL BUILD INTO THE MIDDLE ATLANTIC REGION ON
WEDNESDAY AND PERSIST INTO THURSDAY. SUNNY AND COOLER CONDITIONS
WITH HIGHS IN THE 50S TO LOWER 60S CAN BE EXPECTED WEDNESDAY. AS THE
HIGH SHIFTS TO THE EAST ON THURSDAY...WINDS WILL SHIFT INTO THE
SOUTH AND SOUTHWEST WHICH WILL PUMP MILDER AIR INTO THE FORECAST
AREA. TEMPERATURES WILL LIKELY MODERATE INTO THE 60S TO THE LOWER
70S AREA WIDE...PERHAPS A FEW MIDDLE 70 DEGREE READINGS OVER CENTRAL
VA. SHOWER CHANCES WILL BEGIN TO INCREASE FROM WEST TO EAST LATER
THURSDAY...AHEAD OF THE NEXT COLD FRONT AND AREA OF LOW PRESSURE.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE CONTINUES TO MOVE OFFSHORE WHILE COLD FRONT
APPROACHES THURS NIGHT STARTING A POSSIBLE EXTENDED RAIN EVENT.
COLD FRONT MOVES ACROSS THE CWA ON FRI. PRECIP MOVES FROM WEST TO
EAST AND LASTS INTO SAT AS A LOW PRESSURE BRINGS MOISTURE FROM THE
GULF FRI INTO SAT AFTERNOON. HIGH PRESSURE BUILDS IN ON SAT NIGHT.
WEAK COLD FRONT MAY BRING SOME PRECIP SUN AFTERNOON INTO NIGHT.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
THE DENSE 5-8KFT CLOUD DECK HAS DISPERSED TO A FEW/SCT BATCH OVER
MUCH OF THE AREA. SKIES WILL CLEAR OUT CLOSER TO SUNSET...AS WELL
AS THE GUSTY SFC CONDS. WINDS WILL PEAK W/ GUSTS IN THE 25-30KT
RANGE BEFORE 00Z...THEN SUBSIDE AFTERWARD. WINDS WILL PICK UP OUT
OF THE SW POST DAWN TUE...GUSTS WILL QUICKLY START WELL INTO THE
20-30KT RANGE ALONG W/ A COLD FRONT AND SOME SCATTERED SHOWERS
TMRW AFTN.

RAIN/SHOWERS WILL END FROM WEST TO EAST BY TUESDAY NIGHT. VFR
CONDITIONS WILL RETURN TO THE TERMINALS BY 06Z AND PERSIST THROUGH
THURSDAY EVENING. THE NEXT COLD FRONT AND AREA OF LOW PRESSURE
WILL APPROACH FROM THE WEST LATER THURSDAY NIGHT BRINGING A CHANCE
FOR SHOWERS.

COLD FRONT APPROACHES THURS NIGHT AND MOVES ACROSS ON FRI...
BRINGING RAIN THROUGH SAT. WINDY CONDITIONS ARE EXPECTED BEHIND
COLD FRONT.

&&

.MARINE...
SCA REMAINS REMAINS IN EFFECT ACROSS BAY/TP THRU MID-EVE. WNW
WINDS WILL CONTINUE TO GUST IN THE 20-30KT RANGE W/ ONLY A FEW
NEAR 30KT GUSTS EXPECTED OVER THE NEXT FEW HRS. WINDS DIMINISH
LATE TONIGHT BUT INCREASE QUICKLY TUE MRNG POST DAWN...WELL INTO
SCA RANGE BUT LATE MRNG. HOWEVER...A FAST-MOVING AND POTENT UPPER
LOW WILL SLIDE THRU THE REGION TMRW...SPREADING LOW END GALE GUSTS
AHEAD OF A COLD FRONT. GALES MAY ALSO BE PRESENT W/ RAIN SHOWERS
SO A GALE WARNING IS IN EFFECT FOR THE MIDDAY HRS...SCA CONDS WILL
CONTINUE INTO THE LATE NIGHT HRS OVER MUCH OF THE WATERS.

SMALL CRAFT CONDITIONS LIKELY ON THE MIDDLE AND LOWER BAY
AND LOWER TIDAL POTOMAC TUESDAY NIGHT. WINDS WILL FALL BELOW SCA
LEVELS ON WEDNESDAY BUT WILL INCREASE OUT OF THE SOUTH ON THURSDAY.
SOUTHERLY CHANNELING WILL BE POSSIBLE AND WINDS COULD REACH SCA.

SCA LIKELY FRI NIGHT INTO SAT BEHIND COLD AS WINDY CONDITIONS
DEVELOP.

&&

.FIRE WEATHER...
A COUPLE OF QUICK-MOVING LOW PRESSURE SYSTEMS W/ DRY AIR AND
BREEZY CONDS - TODAY AND AGAIN ANOTHER TMRW - WILL SET UP PARTS
OF THE AREA FOR ENHANCED FIRE WX CONCERNS. A DAY OF BREEZY NW
WINDS TODAY AND GUSTY SW WINDS ON TUE WILL HELP DRY OUT FUEL
MOISTURES OVER THE SW PORTION OF THE AREA - THE LOWER NRN SHEN
VLY/N CNTL VA PIEDMONT. MUCH OF THE PRECIP IS EXPECTED TO STAY
NORTH OF THESE AREAS AND GUSTY WINDS DROP RH VALUES DOWN INTO THE
20-30 PERCENT RANGE. STILL COORDINATING POSSIBLE FIRE WX HEADLINES
FOR TUE AFTN/EVE.

&&

.TIDES/COASTAL FLOODING...
WATER LEVELS STILL HOVERING IN THE 1-1.5` ABOVE NORMS RANGE AND
ANNAPOLIS HAS PEAKED JUST ABOVE 2` AT HIGH TIDE. HOWEVER...WINDS
HAVE SWITCHED TO WSW AND NW IN SOME CASES AT FAIRLY BREEZY WHICH
IS BEGINNING TO TAKE EFFECT ON WATER LEVELS...STARTING THE GRADUAL
DECREASE BACK TOWARD 1` ABOVE LEVELS AND LOWER. THESE STRONGER
WINDS WILL GRADUALLY SUBSIDE LATER TONIGHT AND ANOTHER SURGE OF
SWLY WINDS WILL START UP ON TUE MRNG. THIS MAY BEGIN TO PICK UP
ANOMALIES AND INCREASE THEM TO SIMILAR OR HIGHER LEVELS INTO THE
AFTN HRS ON TUE...BEFORE ANOTHER COLD FRONT MOVES THRU W/ YET
ANOTHER SURGE OF STRONG NW WINDS TO TAKE LEVELS BACK DOWN AGAIN.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
     ANZ530>543.
     SMALL CRAFT ADVISORY FROM 6 PM TUESDAY TO MIDNIGHT EDT TUESDAY
     NIGHT FOR ANZ530-531-535-536-538-539.
     GALE WARNING FROM 11 AM TO 6 PM EDT TUESDAY FOR ANZ530>543.
     SMALL CRAFT ADVISORY FROM 6 PM TUESDAY TO 6 AM EDT WEDNESDAY
     FOR ANZ532>534-537-540>543.

&&

$$
SYNOPSIS...GMS
NEAR TERM...GMS
SHORT TERM...KRW
LONG TERM...IR
AVIATION...GMS/KRW/IR
MARINE...GMS/KRW/IR
FIRE WEATHER...GMS
TIDES/COASTAL FLOODING...GMS



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