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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 240108
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
908 PM EDT THU MAY 23 2013

.SYNOPSIS...
-- Changed Discussion --
A COLD FRONT WILL CROSS THE MID-ATLANTIC REGION TONIGHT. AN UPPER
LEVEL LOW WILL RESIDE OVER THE AREA ON FRIDAY...THEN CANADIAN HIGH
PRESSURE WILL BUILD OVERHEAD FOR THE MEMORIAL DAY WEEKEND. A WARM
FRONT WILL PASS THROUGH THE AREA DURING THE EARLY TO MIDDLE
PORTION OF NEXT WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH FRIDAY/...
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CDFNT IN/NEAR THE SHEN VLY ATTM. AFTER AN AFTN WHERE STORMS WERE
SCTD AND LACKED ORGANIZATION...FINALLY HV A CONCENTRATED STRUCTURE
TO WORK OFF OF. HWVR...W/ LOSS OF DIURNAL HEATING WE/RE LOSING
WHAT SEVERITY WE HAD. CENTRAL VA HAS BEEN LARGELY UNTAPPED...AND
XPCT TSRA TO HV MORE LIFE THERE. ELSW...THE HVY RAFL WL BE THE
BIGGER IMPACT. LWX RAOB DEMONSTRATES THIS PREMISE...W/ MORE CINH
THAN CAPE AND 1.33 INCH PWAT. WL KEEP POPS HIGH TIL FROPA...THEN
SCALE BACK. WIND SHIFT TO THE NORTHWEST OCCURS BEHIND THE FRONT
OVERNIGHT...AND DEWPOINTS WILL BEGIN TO DECREASE WITH COOLER AIR
MOVING IN FOR FRIDAY.

FRIDAY WILL CERTAINLY FEEL LIKE A DIFFERENT DAY WITH MAXIMA
RELUCTANT TO RISE MUCH DURING THE DAY WITH LOW LEVEL COLD
ADVECTION AT PLAY AND AN UPPER LOW OVERHEAD. MAXIMA IN THE LOWER
TO MID 60S CAN BE EXPECTED. DECENT GRADIENT WITH COLD ADVECTION
WILL BRING A WINDY DAY...WITH GUSTS POSSIBLY OVER 35 MPH AT TIMES.

WITH THE UPPER LOW OVERHEAD EXPECT PLENTY OF CLOUDS AND ALSO
SCATTERED SHOWERS PARTICULARLY ACROSS THE NORTHERN PORTION OF THE
CWA. SHOWERS MAY PRODUCE STRONGER WIND GUSTS AND ALSO CAN/T RULE
OUT SOME SMALL HAIL DUE TO COLD AIR ALOFT.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
UPPER LOW DRIFTS TO THE NORTHEAST ON SATURDAY...AS HIGH PRESSURE
BUILDS IN FOR THE REST OF THE WEEKEND. IT LOOKS LIKE WINDS STAY UP
FRIDAY NIGHT...SO NO FROST IS EXPECTED. BUT TEMPERATURES COULD
DROP CLOSE TO FREEZING OVER THE HIGHLANDS LATE FRIDAY NIGHT.
ANOTHER WINDY AND COOL DAY IS EXPECTED ON SATURDAY ALTHOUGH SOME
SUNSHINE SHOULD MAKE A RETURN. MODERATING TEMPERATURES AND
SUNSHINE ARE EXPECTED SUNDAY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
H5 RISES THROUGH ENTIRE LONG TERM AS BERMUDA HIGH STARTS SETTING UP
AT THE BEGINNING OF THE PERIOD WITH WARM FRONT PASSAGE LIKELY ON
TUESDAY PER 12Z GFS. MONDAY APPEARS STABLE WITH LITTLE OR NO MODEL
CAPE. ON TUESDAY...INSTABILITY STARTS TO WORK INTO THE SHEN VALLEY
WITH WEDNESDAY AND THURSDAY HAVING MODERATE INSTABILITY ACROSS
ENTIRE CWA.

MAX TEMPS MONDAY AND TUESDAY ARE AROUND CLIMO...THEN INCREASING UP
TO 10 DEG ABV CLIMO WITH MAX TEMPS APPROACHING 90 WEDNESDAY AND
THURSDAY.

&&

.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
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SHRA/TSRA IN METRO BALT AND DOWN THE SHEN VLY. FLGT RESTRICTIONS
ATTM GNLY MVFR...ALTHO CUD HV LCL IFR W/IN SHRA/TSRA. THERE MAY BE
A FEW SHRA THEREAFTER...AS WELL AS OCNL MVFR CIGS. CUD BE
CONTENDING W/ A LTL FOG AS WELL TIL FROPA.

A COLD FRONT MOVES THROUGH THE AREA OVERNIGHT WITH A WIND SHIFT.
COOLER/DRIER AIR WL TAKE CARE OF ANY RESIDUAL FOG. EXPECT GUSTY
NORTHWEST WINDS ON FRIDAY...WITH SCATTERED SHOWERS THAT MAY
PRODUCE GUSTIER WINDS.

STRONG NWLY FLOW CONTINUES THROUGH SATURDAY AS THE UPR LOW
REMAINS IN THE REGION AND SFC HIGH PRESSURE BUILDS. VFR EARLY NEXT
WEEK IN A CANADIAN AIRMASS BEFORE A MIDWEEK WARM FRONT.
-- End Changed Discussion --

&&

.MARINE...
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ASIDE FM DRUM PT-SMITH PT AND ADJACENT TANGIER SOUND...WINDS HVNT
REALLY BEEN REACHING SCA CRIT. EVEN IN THE MID BAY...SPDS STARTING
TO SUBSIDE. WL ALLOW SCA TO EXPIRE AT 10 PM. THAT/S NOT TO SAY
THERE WONT BE GUSTY WINDS...BUT THEY WL BE ASSOCD W/ SHRA AND TSRA
CROSSING ALONG AND AHEAD OF CDFNT. ANTICIPATE SPECIAL MARINE
WARNINGS WL BE REQD OVNGT.

COLD FRONT MOVES THROUGH OVERNIGHT WITH WINDS SHIFTING
TO THE NORTHWEST. THESE WINDS WILL BE GUSTY ON FRIDAY...FOR A
SOLID SMALL CRAFT ADVISORY. MAY EVEN FLIRT WITH GALES DUE TO
GRADIENT EFFECTS ALONE. IN ADDITION...SCATTERED SHOWERS MAY
PRODUCE STRONGER WIND GUSTS.

NWLY FLOW WITH GUSTS 25 TO 30 KT THROUGH SATURDAY AS AN UPR LOW
PERSIST OVER THE REGION AND SFC HIGH PRESSURE BUILDS. MORE
TRANQUIL WEATHER EARLY NEXT WEEK UNDER A CANADIAN AIRMASS.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
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ANOMALIES RUNNING 1/2 FT ABOVE NORMAL TNGT. NO COASTAL FLOOD
ADVISORY IS EXPECTED. WINDS WILL SHIFT TO THE NORTHWEST OVERNIGHT
INTO FRIDAY BEHIND A COLD FRONT...BRINGING A RETURN TO NORMAL AT A
MINIMUM...AND MORE LIKELY BLOW OUT CONDS.
-- End Changed Discussion --

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR
     ANZ531>534-537>543.
     SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO 6 AM EDT SATURDAY FOR
     ANZ530>543.
-- End Changed Discussion --

&&

$$
SYNOPSIS...BPP
NEAR TERM...HTS/BPP
SHORT TERM...BPP
LONG TERM...LEE
AVIATION...HTS/BPP/BAJ
MARINE...HTS/BPP/BAJ
TIDES/COASTAL FLOODING...HTS