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000
FXUS61 KLWX 120253
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1053 PM EDT SAT MAY 11 2013

.SYNOPSIS...
A COLD FRONT WILL TRACK ACROSS THE CHESAPEAKE BAY LATE THIS
EVENING. A STRONGER COLD FRONT WILL CROSS THE MID- ATLANTIC
SUNDAY MORNING. AN UPPER TROUGH WILL DRIFT ACROSS THE REGION
MONDAY...WITH HIGH PRESSURE BUILDING OVER THE MID- ATLANTIC
TUESDAY...BEFORE ANCHORING OFF THE COAST THROUGH LATE NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
WEAK PRIMARY COLD FRONT SLOWLY WORKING THROUGH THE CWA. PREFRONTAL
SHOWERS/THUNDERSTORMS NOW EAST OF I-95 AND ISOLATED STRONG
THUNDERSTORMS COULD CONTINUE TO UNTIL MIDNIGHT OVER SRN MD. CLOUDS
PERSIST TONIGHT THE ACTUAL/REINFORCING COLD FRONT NOW OVER CNTRL
OHIO (AS OF 0130Z). UPSLOPE PRECIP EXPECTED UNTIL THE COLD FRONT
ARRIVES. EXPECT SOME SNOW FLAKES ABOVE ABOUT 3500 FT LATE
TONIGHT... WITH THE COLUMN DRYING OUT THROUGH MID-MORNING SUNDAY.

WITH CAA SLOW TO ENTER THE CWA OVERNIGHT...EXPECT MIN TEMPS MID
TO UPR 30S ON RIDGES IN THE POTOMAC HIGHLANDS...MID 40S IN VALLEYS
EAST OF THERE...LOW TO MID 50S EAST OF THE BLUE RIDGE.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
HIGH PRES BLDS INTO THE RGN TMRW. BRZY CONDS..CLOUDY MORNING
BEFORE COLD FRONT MOVES THROUGH...THEN M SUN SKIES..HIGHS 65-70 E
OF THE MTNS...60-65 W.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
UPDATED MIN TEMPS FOR SUN/MON NIGHT BASED ON ADJUSTED MEX GUIDANCE
AND ADJUSTED SREF. THIS LOWERED MIN TEMPS. THIS AFTERNOON HIGHLAND AND
PENDLETON INTO A FREEZE WATCH...MORE AREAS THAN THIS MAY SEE
FREEZING CONDS BOTH SUN AND MON NIGHT.

UNSEASONABLY LATE COLD SNAP WILL POSE SOME AGRICULTURAL ISSUES EARLY
NEXT WEEK. COLD HIGH PRES MOVES IN ON W WINDS SUN NIGHT. FREEZING
CONDITIONS CURRENTLY IN THE FORECAST FOR W GRANT AND W PENDLETON
COUNTIES IN WV. HIGH PRES CENTERS OVER THE AREA MON NIGHT WHICH WILL
ALLOW FOR FROST EARLY TUE MORNING OVER THE SHEN VALLEY...N CENTRAL
MD AND POINTS WEST. PATCHY FROST WILL EXTEND EAST OF THE BLUE RIDGE
AS WELL...THO THE BALT AND WASH METRO AREAS SHOULD ESCAPE WITH TEMPS
IN THE UPPER 30S TO LOWER 40S. PATCHY FROST WILL BE CLOSE BY THOUGH.
TUE...MID LEVL WARM FRONT ADVANCES ON AREA FROM MIDWEST BRINGING AN
INCREASE IN CLOUDS.

EURO AND GFS IN PRETTY GOOD AGREEMENT THROUGH THE UPCOMING WEEK. TUE
NIGHT INTO WED THE MID LEVEL WARM FRONT PASSES ENE THRU THE REGION.
SHOULD BE DRY BUT 850MB TEMPS RISE FROM THE SINGLE DIGITS TUE EVE TO
THE MIDDLE TEENS BY WED EVE. THAT IS QUICKLY FOLLOWED BY A SMALL
500MB TROF THAT DEVELOPS A WEAK LOW OVER THE REGION WITH A TRAILING
COLD FRONT LATE THU INTO FRI. A SMALL AREA OF SLIGHTLY COOLER HIGH
PRESSURE TRIES TO NOSE IN FROM THE MIDWEST FOR SAT.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
VFR CONDS XPCTD OVRNGT IN LIGHT NWLY FLOW. SUNDAY NWRLY WINDS WL GUST
INTO 20+ KT RANGE DURG DAYLGT HRS WITH CONTINUED VFR.

VFR CONDITIONS EXPECTED TUE NIGHT THROUGH SATURDAY...EXCEPT IN ANY
SCT TO ISOLATED TSTMS IN THE MID TO LATE WEEK.

&&

.MARINE...
SML CRFT ADVSRY UNTIL MIDNIGHT WITH TSTMS MOVING THROUGH. MAY NEED
SPECIAL MARINE WARNINGS FOR SRN MD WATERS UNTIL MIDNIGHT.

SUNDAY HIGH PRES WL BLD INTO THE WATERS. AN SCA IS IN EFFECT FOR
ALL WATERS.

SMALL CRAFT ADVISORIES ARE NOT EXPECTED TUE NIGHT THROUGH SATURDAY.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...FREEZE WATCH FROM LATE SUNDAY NIGHT THROUGH MONDAY MORNING FOR
     VAZ503-504.
WV...FREEZE WATCH FROM LATE SUNDAY NIGHT THROUGH MONDAY MORNING FOR
     WVZ505-506.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 8 PM EDT SUNDAY FOR
     ANZ530>543.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ533-534-
     537-541>543.

&&

$$
UPDATE...JACKSON