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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 180739
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
339 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 EARLY WEDNESDAY. AN
AREA OF LOW PRESSURE OVER KENTUCKY WILL TRACK SOUTH OF THE AREA
TONIGHT. HIGH PRESSURE WILL RETURN TO THE AREA WEDNESDAY....MOVING
OFFSHORE FOR THE WEEKEND.
-- End Changed Discussion --

&&

.NEAR TERM /TODAY/...

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MONDAY SAW PLENTY OF MOISTURE TRAPPED IN THE LOWEST LEVELS OF THE
ATMOS. EVEN WEAK CONVERGENCE CAUSED QUICK ISOLATED CELLS DEVELOPING
AND SPLITTING UNDER THE STRAIGHT-LINE HODOGRAPH...THEN PRODUCING
OUTFLOW THAT PRODUCED MORE STORM CELLS. MUCH OF THIS ACTIVITY
OCCURRED EITHER NEAR THE HIGHER TERRAIN OR THE I-95 CORRIDOR WHERE
BAY/RIVER BREEZES RESIDED. THIS ACTIVITY HAS SINCE SUBSIDED BUT NOT
BEFORE DROPPING SEVERAL INCHES OF RAIN ACROSS A LONG-THIN STRIPE OF
LAND JUST NORTH OF I-64 FROM STAUNTON TO CHARLOTTESVILLE.
THEREFORE...A FLASH FLOOD WATCH IS IN EFFECT FOR THESE AREAS TODAY.

AFTER THE ISOLATED ACTIVITY FROM YESTERDAY DISSIPATED...A LARGER
VIEW SHOWED LARGER BUT STILL RELATIVELY WEAK/DISORGANIZED COMPLEXES
STILL CHURNING-OUT WIDESPREAD RAINS ACROSS THE TENN RVR VLY AND
ALONG THE SRN ATLC COAST. THE TENN VLY ACTIVITY IS ASSOCIATED W/ A
STRENGTHENING UPPER SHORTWAVE THAT WILL EVENTUALLY SLIDE ACROSS THE
SRN TIER OF THE AREA OVER THE COURSE OF TODAY. THE PRESENCE OF THIS
FEATURE ADDS AN ELEMENT OF BETTER ORGANIZATION...MORE STEERING FLOW
AND LESS "RANDOM" CONVECTION FOR MUCH OF THE AREA.

WITH A STILL FAIRLY UNSTABLE ATMOS OVERHEAD...BUT THE SHORTWAVE WILL
BEGIN TO REDUCE THIS AS IT MOVES THRU LATER THIS AFTN/EVE. AS THE
LEADING EDGE OF THE SHORTWAVE APPROACHES LATER THIS MRNG...SCATTERED
WEAK CONVECTION WILL DEVELOP QUICKLY AND SPREAD FURTHER EAST ACROSS
THE AREA. BY LATE MRNG...PRECIP SHOULD BE SPREADING ACROSS MUCH OF
THE MID ATLC...W/ EMBEDDED POCKETS OF WEAK CONVECTION...HEAVY RAIN
AND GUSTY WINDS FROM THE STRONGER ACTIVITY. MODEL SOUNDINGS ACROSS
THE REGION SHOW A GRADUAL DECREASE IN CAPE AND OVERALL FAVORABLE SVR
WX PARAMETERS HEADING INTO THE AFTN HRS...AS HEATING DOESN`T LOOK TO
BE SUBSTANTIAL W/ INCREASING CLOUDS FROM FALLING PRECIP THROUGHOUT
THE LATE MRNG/EARLY AFTN.
-- End Changed Discussion --

&&

.SHORT TERM /TONIGHT/...

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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.
-- End Changed Discussion --

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...

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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.
-- End Changed Discussion --


&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...

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WITH THE MID ATLC CLEAR OF ANY EARLIER ISOLATED SHOWERS/TSTMS...THE
AREA IS PREPARING FOR A BIT MORE WIDESPREAD SHOWERS/TSTMS IN THE
COMING HRS. LATER THIS MRNG AND INTO THE AFTN HRS...SCATTERED
SHOWERS AND A FEW ISOLATED TSTMS WILL DEVELOP AND SPREAD ACROSS THE
REGION...AHEAD OF AN APPROACHING UPPER LEVEL DISTURBANCE. MUCH OF
THIS ACTIVITY WILL PUSH OFF THE COAST LATER THIS EVE...W/ ONLY A FEW
LINGERING SHOWERS/TSTMS HEADING INTO THE OVERNIGHT HRS.

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

&&

.MARINE...

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WITH HIGH PRESSURE NOW WELL OFF THE COAST AND COUPLE OF WEAK UPPER
DISTURBANCES SLIDING OVERHEAD TODAY AND TOMORROW...WINDS WILL
SUBSIDE OVER THE WATERS TO JUST A LIGHT BREEZE FOR MUCH OF THIS
PERIOD. ONLY THE ISOLATED TSTM ACTIVITY POSSIBLE LATER TODAY AND
AGAIN ON WED IS EXPECTED TO PRODUCE GUSTS OVER THE WATERS.

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

&&

HYRDOLOGY...

HVY RAIN MON ACROSS AUGUSTA..ALBEMARLE...AND NELSON COUNTIES
CAUSED FLSH FLD PROBLEMS W/ ROAD CLOSURES. FLD WRNG RMNS IN EFFECT
UNTIL 445 AM. GIVEN BAROCLINIC LEAF SEEN ON STLT ACROSS KY/WRN
W.V. IT IS LKLY THE SAME AREA WL BE XPRNCG RAFL TDA. A FLSH FLD
WATCH IS BEING ISSUED TDA FOR THIS REASON.

&&

COMMUNICATIONS...

B4 MDNGT 4 NWR XTMRS WENT DOWN SIMULTANEOUSLY - LKLY A PHONE
COMPANY PROBLEM. THE PHONE CO. HAS BEEN NOTIFIED. NO TIME ESTIMATE
ON WHEN THIS PROBLEM WL BE FIXED.


&&

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

&&

$$
PRODUCTS...GMS/WOODY!