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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 181444
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1044 AM EDT TUE JUN 18 2013

.SYNOPSIS...
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A WEAK COLD FRONT APPROACHING FROM THE NORTH WILL STALL OVER THE
MID ATLANTIC TODAY...MOVING SOUTH OF THE REGION TONIGHT.
MEANWHILE...AN AREA OF LOW PRESSURE OVER THE SOUTHERN APPALACHIANS WILL
TRACK SOUTH OF THE AREA TODAY. HIGH PRESSURE WILL RETURN TO THE
AREA WEDNESDAY....MOVING OFFSHORE FOR THE WEEKEND.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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ONE FRONTAL BOUNDARY WAS LOCATED ACROSS SOUTHERN VIRGINIA THIS
MORNING...WITH LOW PRESSURE NOTED OVER SOUTHWEST VIRGINIA.
ANOTHER COLD FRONT WAS LOCATED ALONG THE MASON DIXON LINE. LOW
PRESSURE WILL RIDE ALONG THE SOUTHERN FRONT...MOVING OFF THE COAST
THIS EVENING WHILE THE NORTHERN FRONT SINKS SOUTH AND MOVES
THROUGH LATER TODAY.

SHOWERS AND EMBEDDED THUNDERSTORMS WILL CONTINUE TO EXPAND
NORTHEAST THROUGH THE CWA TODAY PER WRF-ARW/HRRR GUIDANCE. WILL BE
UPGRADING POPS FOR CATEGORICAL ACROSS MOST AREAS OF THE CWA.

PRIMARY CONCERN TODAY IS HEAVY RAINFALL AND LOCALIZED
FLOODING...PARTICULARLY IN SUSCEPTIBLE AREAS. THESE INCLUDE
PORTIONS OF THE CENTRAL SHENANDOAH VALLEY AND CENTRAL VIRGINIA
FOOTHILLS WHICH RECEIVED HEAVY RAIN LAST EVENING...AND ALSO INTO
THE METRO AREAS WHICH HAVE LOW FLASH FLOOD GUIDANCE.

GIVEN CLOUDS/SHOWERS...THIS WILL LIMIT DESTABILIZATION SOME BUT
LAPSE RATES LOOK BETTER THAN YESTERDAY AND MODELS/MODIFIED
SOUNDING DOES SHOW SOME CAPE. SO EMBEDDED THUNDERSTORMS MAY HAVE
THE POTENTIAL TO PRODUCE STRONG AND POSSIBLY DAMAGING WINDS THIS
AFTERNOON AND PERHAPS SOME HAIL.

ADJUSTED MAXIMA DOWNWARD BY A DEGREE OR TWO FROM PREVIOUS FORECAST
GIVEN CLOUDS/PRECIP.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
THE SHORTWAVE WILL THEN MOVE INTO THE AREA LATER THIS AFTN...
COLLECTING AND COMBINING MUCH OF THE ONGOING PRECIP...AND BEGIN TO
MOVE IT OFF THE COAST. AFTER ONLY REACHING THE L80S FOR DAYTIME
HIGHS W/ PLENTY OF CLOUD COVER...PERIODIC RAIN SHOWERS AND A SLOWLY
CHANGING AIRMASS - WE`LL DROP DOWN INTO THE L-M60S FOR OVERNIGHT
LOWS. SOME RESIDUAL SHOWER AND WEAK TSTM ACTIVITY WILL CONTINUE LATE
THIS EVE FROM EARLIER OUTFLOW BOUNDARIES...BUT MOST OF THE AREA WILL
BEGIN TO DRY OUT.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE OPERATIVE WORD FOR THE XTND PART OF THE FCST WL BE
"SUMMER"...AS IN "SUMMERY TEMPS WL BE ARRIVING ON THE SUMMER
SOLSTICE"...AND THEN RMNG FOR THE FORESEEABLE FUTURE. LOW PRES WL
BE EXITING THE CST WED MRNG W/ HIGH PRES BLDG IN FM THE UPR
MIDWEST. VERY PLSNT DAYS/NGTS XPCTD WED AND THU W/ HIGHS IN THE
L80S..LOWS RANGING FM THE M50S IN THE HIGHLANDS TO THE M60S IN THE
CITIES.

FRI - THE SOLSTICE. HIGH WL BE MOVG OFF THE CST...HUMIDITY WL
BEGIN TO INCRS. HIGH TEMPS IN THE M80S. SRN RDG WL REALLY BEGIN TO
IMPACT THE MID ATLC THIS WKND. HIGH TEMPS XPCTD TO BE IN U80S/L90S
SAT THRU NEXT TUE. ONLY TSTM CHCS WL LKLY SET UP OVR THE MTNS IN
THE AFTN. WHETHER THESE THEN MOVE E IN THE LATE AFTN/EARLY EVE
WE`LL HV TO WAIT TO SEE.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
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SHOWERS ARE EXPECTED TO MOVE EAST/DEVELOP FURTHER EAST THROUGH THE
MORNING. MOD-HVY RAINFALL MAY OCCUR WITH SHOWERS FOR AT LEAST MVFR
CONDITIONS. GIVEN SOME INSTABILITY MAY HAVE A FEW THUNDERSTORMS
TOO...MAINLY AFTER 18Z SO VCTS REMAINS IN TAFS. FRONTAL BOUNDARY
WILL SINK SOUTH THROUGH THE AREA AS THE DAY PROGRESSES...SWITCHING
WINDS TO THE NORTH. MUCH OF THE ACTIVITY WILL WANE DURING THE
EVENING HOURS AS A WAVE OF LOW PRESSURE MOVES OFF THE COAST.

IN THE XTND...VFR CONDS XPCTD.
-- End Changed Discussion --

&&

.MARINE...
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WEAK GRADIENT OVER THE WATERS TODAY WILL KEEP WINDS BELOW SCA
THRESHOLDS. FRONT WILL SINK SOUTH LATER TODAY AS A WAVE OF LOW
PRESSURE PASSES BY THE SOUTH. ANY THUNDERSTORMS WILL HAVE THE
POTENTIAL TO PRODUCE STRONG GUSTY WINDS. NORTH WINDS OCCUR BEHIND
THE FRONT TONIGHT BUT ARE EXPECTED TO ALSO REMAIN BELOW SCA.

WINDS XPCTD TO RMN BLO SCA VALUES IN THE XTND.
-- End Changed Discussion --

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
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DC...NONE.
MD...NONE.
VA...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR VAZ025-026-
     036-037-503-504.
WV...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR WVZ505-506.
MARINE...NONE.
-- End Changed Discussion --

&&

$$
BPP/GMS/WOODY!