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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 071334
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
834 AM EST FRI MAR 7 2014

.SYNOPSIS...
LOW PRESSURE WILL MOVE UP THE NORTH CAROLINA COAST TODAY BEFORE
MOVING OUT TO SEA TONIGHT. HIGH PRESSURE BRIEFLY RETURNS SATURDAY
BEFORE A COLD FRONT MOVES THROUGH SATURDAY NIGHT. HIGH PRESSURE WILL
BUILD OVERHEAD EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
NRN TIER OF COUNTIES UNDER THE WINTER WX ADVISORY...ROUGHLY THE
I-66 AND RT-50 CORRIDOR WERE CANCELLED. PRECIP SHIELD CONTINUES
TO ERODES AS IT MOVES NWD INTO INCREASINGLY DRIER AIR FROM HIPRES
TO OUR NORTH. POPS HAVE BEEN LOWERED ACROSS THESE AREAS. PRECIP
MAY BRIEFLY MOVE INTO DC-ANNAPOLIS AREA THIS AFTN...BUT TEMPS WILL
BE ABOVE FREEZING BY THEN...RESULTING IN JUST RAIN.

PREVIOUS DISCUSSION...
STRENGTHENING COASTAL LOW PRESSURE SYSTEM OFF THE CAROLINA
COAST...W/ THE OVERRUNNING PRECIP SHIELD EXTENDING BACK ONSHORE
WELL INTO THE SRN APLCNS. THE SFC LOW JUST OFF THE SC COAST AND
WILL DECELERATE AS THE UPPER LEVEL SYSTEM SLOWS DOWN...PIVOTS AND
THEN DRAGS THE REMAINDER OF THE SYSTEM OFF THE COAST LATER TODAY.
THE NRN EDGE OF THE PRECIP SHIELD WILL GRADUALLY MAKE A PUSH
FURTHER NORTH INTO CNTRL VA AND THE NORTH- CNTRL VA PIEDMONT MORE
TOWARD THE PREDAWN HRS.

WHILE THE LOWER-RES REGIONAL SCALE MODELS HAVE BACKED OFF A BIT
ON THIS LEADING EDGE`S NWD PROGRESS...HI-RES NEAR TERM MODELS LIKE
THE HRRR AND 00Z WRF-NMM4KM PIVOT EDGE OF THE PRECIP ON A LINE FROM
CHO TO DCA AND EAST. THE HIGHER PROBS FOR MEASURABLE FZRA ACCUM WILL
BE OVER THE SRN TIER COUNTIES/LOCALES OF THE CWA W/ A TAPERING
EFFECT BACK TOWARD THE BLUE RIDGE/I-66 CORRIDOR BUT STILL THE
POTENTIAL FOR SOME BRIEF FZDZ IN POCKETS OUT AHEAD OF THE LEADING
EDGE.

VERY LIGHT PRECIP REGARDLESS...W/ ONLY TRACE AMOUNTS OF FZRA
EXPECTED FOR THE NRN TIER OF THE ADVISORY AND SLIGHTLY HIGHER
BORDERING THE CNTRL VA LOCALES. KEEPING THE WINTER WX ADVISORY
INTACT FOR THE INCOMING PRECIP POTENTIAL...EVEN IF SOME OF THE NRN
FRINGE AREAS OF THE ADVISORY ARE BRIEFLY BRUSHED W/ A WAVE OF LIGHT
PRECIP-DRIZZLE HEADING INTO THE PRE/POSTDAWN HRS. THE MAIN WINDOW
FOR THIS POTENTIAL IS BETWEEN 6-10A W/ A SLIGHT BUFFER ON EITHER
SIDE BECAUSE SFC TEMPS ARE BELOW FREEZING AREAWIDE.

HIGHS TODAY A BIT HIGHER THAN YESTERDAY BUT THE DAYTIME HRS WILL BE
CLOUDY...KEEPING OUR POTENTIAL WARM-UP MODERATED W/ ONLY M-U30S
EXPECTED. A SHARP CLOUD DECREASE WILL OCCUR LATER THIS EVE...AS THE
EDGE OF THE PRECIP SHIELD PIVOTS BACK TOWARD THE COAST AND MOVES
WELL E OF THE AREA. THE WRN EDGE OF THE CLOUD DECK WON`T BE FAR
BEHIND...W/ SKIES GENERALLY CLEARING OUT LATE TONIGHT. THE HEFTY
CLOUD SHIELD TODAY WILL KEEP DEWPOINTS INTACT IN THE FAIRLY "MOIST"
RANGE...WHICH WILL KEEP OUR LOW TEMPS TONIGHT MODERATED...ONLY
DROPPING A COUPLE/FEW DEG BELOW FREEZING.
-- End Changed Discussion --

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
HIGH PRESSURE WILL BUILD OVER THE GULF COAST STATES SATURDAY WHILE A
COLD FRONT APPROACHES FROM THE NORTHWEST. A DOWNSLOPING WESTERLY
FLOW IS EXPECTED AHEAD OF THE FRONT...AND WITH SOME SUNSHINE IT WILL
TURN OUT TO BE NOTICEABLY MILDER COMPARED TO RECENT DAYS. MAX TEMPS
WILL REACH THE MID TO UPPER 50S ACROSS MANY LOCATIONS...WITH LOWER
TO MIDDLE 60S EXPECTED ACROSS CENTRAL VIRGINIA. A COLD FRONT WILL
PASS THROUGH THE REGION SATURDAY NIGHT. A COUPLE SHOWERS CANNOT BE
RULED OUT...BUT MOST OF THE TIME WILL BE DRY. HOWEVER...THERE IS THE
CHANCE FOR SOME SNOW SHOWERS FOR LOCATIONS ALONG AND WEST OF THE
ALLEGHENY FRONT DUE TO AN UPSLOPE COMPONENT TO THE LOW-LEVEL FLOW.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD OVERHEAD BEHIND THE FRONT SUNDAY...BRINGING
SUNSHINE AND DRY CONDITIONS ALONG WITH SEASONABLE TEMPERATURES.

HIGH PRESSURE WILL SETTLE OVER OVER THE GULF COAST STATES EARLY NEXT
WEEK WHILE A COLD FRONT APPROACHES FROM THE NORTH AND WEST. MORE
DOWNSLOPING WESTERLY WINDS ARE EXPECTED ALONG WITH SOME SUNSHINE.
THIS WILL ALLOW FOR MILD CONDITIONS.

THE COLD FRONT WILL MOVE INTO THE REGION TUESDAY NIGHT AND LOW
PRESSURE IS EXPECTED TO DEVELOP ALONG THE BOUNDARY...BRINGING THE
NEXT SIGNIFICANT CHANCE FOR PRECIPITATION WEDNESDAY INTO THURSDAY.
DETAILS REMAIN UNCERTAIN THIS FAR OUT.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS ARE EXPECTED MOST OF THE TIME SATURDAY THROUGH EARLY
NEXT WEEK. A COLD FRONT MAY BRING A FEW SHOWERS SATURDAY NIGHT AND
CIGS COULD BRIEFLY APPROACH MVFR LEVELS DURING THIS TIME.

SOLID MVFR CIGS SPILLING NWD INTO THE REGION...WILL APPROACH IFR
TOWARD DAWN BUT HOVER JUST INTO THE HIGH-END IFR RANGE. THE WINDOW
FOR THE LOWEST CIGS WILL BE THE MID MORNING HOURS...THEN DRIER AIR
WILL BEGIN TO BRING THEM BACK UP SLOWLY THROUGHOUT THE AFTN HRS.
NOT UNTIL LATE THIS EVE THOUGH WILL SKIES BEGIN TO CLEAR OUT AND THE
AREA IMPROVES OUT OF THE MVFR RANGE.

A BAND OF LIGHT PRECIP WILL PIVOT TOWARD THE AREA - MAINLY THE I-95
CORRIDOR OF DC TO KCHO IN THE NEXT SEVERAL HRS...W/ SOME LIGHT FZRA
AND FZDZ POSSIBLE ACROSS THESE AREAS THRU THE POSTDAWN HRS. WINDS
WILL STAY BREEZIER OVER THE CHESAPEAKE BAY REGION BUT TAPER OFF A
BIT TO A STEADY N-NELY FLOW ALONG THE I-95 CORRIDOR AND WEST.

&&

.MARINE...
HIGH PRESSURE WILL BUILD OVERHEAD SATURDAY BEFORE A COLD FRONT
PASSES THROUGH SATURDAY NIGHT. WIND GUSTS MAY COME CLOSE TO SCA
CRITERIA BEHIND THE FRONT LATE SATURDAY NIGHT INTO SUNDAY. HIGH
PRESSURE WILL IMPACT THE WATERS EARLY NEXT WEEK.

BREEZY AND LOW-MID SCA RANGES OVER THE LOWER MD BAY...TAPERING OFF
TOWARD THE MID BAY. WINDS WILL BUMP BACK UP INTO SCA RANGE ACROSS
THE WHOLE MD BAY AND TP LATER THIS MRNG AND INTO THE AFTN/EVE HRS AS
A COASTAL LOW APPROACHES FROM THE CAROLINAS AND MOVES PARALLEL TO
THE COASTLINE.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...NONE.
MD...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR MDZ016>018.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ025-026-
     029-036>040-050>052-055>057-502.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ530>543.
-- End Changed Discussion --

&&

$$
SYNOPSIS...BJL
NEAR TERM...JRK/GMS
SHORT TERM...BJL
LONG TERM...BJL
AVIATION...BJL/GMS
MARINE...BJL/GMS