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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 161349
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
949 AM EDT SUN JUN 16 2013

.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE CAROLINA COAST TODAY AS A SURFACE
TROUGH APPROACHES THIS AFTERNOON. A WEAK COLD FRONT WILL APPROACH
FROM THE NORTH ON MONDAY...BECOMING STATIONARY ALONG THE MASON DIXON
LINE THROUGH TUESDAY. MEANWHILE AN AREA OF LOW PRESSURE WILL PASS
SOUTH OF THE AREA TUESDAY. HIGH PRESSURE THEN RETURNS FOR THE REST
OF THE WEEK INTO THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
HIGH PRESSURE HAS MOVED OFF THE EASTERN SEABOARD. SOUTHERLY FLOW
AROUND THE HIGH WILL CONTINUE TO BRING MOISTURE BACK INTO THE MID-
ATLANTIC REGION TODAY.

THIS MORNING BEGAN WITH A DECK OF MID CLOUDS BUT THOSE HAVE SINCE
THINNED OUT...LEAVING PARTLY SUNNY SKIES. EXPECTATION IS FOR
CLOUDS TO FILL BACK IN BY THE MIDDAY HOURS AS UPSTREAM CLOUDS
AHEAD OF A SHORTWAVE/VORT MAX PUSH TO THE EAST. AFTERNOON WILL
LIKELY TURN OUT MOSTLY CLOUDY.

THERE ARE SHOWERS ASSOCIATED WITH THE SHORTWAVE ACROSS WESTERN
PENNSYLVANIA AND WEST VIRGINIA. THESE TOO WILL MOVE TO THE EAST
WITH TIME AND AFFECT THE CWA. QUESTION IS HOW MUCH INSTABILITY
WILL BE PRESENT FURTHER EAST AS SHORTWAVE MOVES THROUGH. MODEL
SOUNDINGS AT VARIOUS POINTS ONLY SUGGEST 500 TO 1000 J/KG
CAPE...MOST APPARENT IN THE EVENING. SHEAR LOOKS A LITTLE STRONGER
THAN PREVIOUSLY PREDICTED...BUT GIVEN THE LIMITATION IN
INSTABILITY THIS WILL PROBABLY LIMIT A WIDESPREAD SEVERE RISK.
CURRENT EXPECTATION IS FOR A DECENT COVERAGE OF SHOWERS AND
THUNDERSTORMS MAINLY IN THE LATE AFTERNOON AND EVENING TOWARD THE
INTERSTATE 95 CORRIDOR PER THE WRF-ARW/HRRR AND THERE MAY BE SOME
ORGANIZATION TO THE CONVECTION...BUT SEVERE STORMS WITH DAMAGING
WIND/HAIL MAY BE ISOLATED IN NATURE.

SHORTWAVE EXITS THIS EVENING AND A SURFACE TROUGH SAGS ACROSS THE
SOUTHERN CWA. THIS IS WHERE POPS WILL BE FOCUSED FOR THE REMAINDER
OF THE NIGHT.
-- End Changed Discussion --

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
LOW PRESSURE OVER THE SRN PLAINS AS SHOWN IN 00Z NCEP GUIDANCE WILL
BRING AN INCREASE IN MOISTURE TO THE MID ATLANTIC ON TUE AS THE LOW
SYSTEM MOVES EAST. DIFFERENCES IN 00Z GFS/NAM ARE APPARENT BEGINNING
FROM 00Z TUE ON...WITH THE 00Z GFS KEEPING SURFACE LOW SYS WILL SOUTH
OF OUR CWA WHILE THE 00Z/NAM IS MUCH FURTHER NORTH WHILE 21Z SREF IS
JUST SOUTH OF THE NAM POSITION WITH THE LOW ON TUE. WILL HEDGE MORE
TO 00Z GFS SOLUTION...WHICH BRINGS LIKELY CHANCES OF PRECIP UP DURING
DAY ON TUE. 00Z/GFS SHOWS GOOD FRONTAL BANDING POTENTIAL FOR
PRECIPITATION ORIENTED EAST-WEST ACROSS THE REGION. HAVE SHADED THE
POP CHANCES FROM N-TO-S FROM CHANCE TO LIKELY. TUE NGT...LOW PRES
MOVES OFF THE CAROLINA COAST AND PRECIP SHOULD END AS IT MOVES OUT.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
SFC HIGH PRESS OF 1020 HPA AS ADVRTZED IN 00Z/GFS WILL HELP TO PUSH
THE FRONT SOUTH OF REGION WED. 00Z MDLS CONSISTENT WITH BOTH GFS AND
ECMWF SHOWING HIGH PRESSURE IN CONTROL REST OF WEEK WITH ONLY SMALL
VARIATIONS IN POSITION OF HIGH. 00Z ECMWF SHOWS SFC WINDS MORE
EASTERLY STARTING ON THU...AS CLOUDS/MOISTURE STAY S WITH FRONTAL
ZONE BY WEEKS END. HIGH PRES EXPECTED TO CONTINUE THROUGH WEEKEND.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
VFR CONTINUES INTO TODAY AS HIGH PRESSURE MOVES OFF THE CAROLINA
COAST ALLOWING RETURN SWLY FLOW. EXPECT SCATTERED THUNDERSTORMS
AROUND DURING THE AFTERNOON AND EARLY EVENING. VCTS MAY BEGIN A
LITTLE TOO SOON IN THE TAFS AND MAY HAVE TO DELAY THIS BY A COUPLE
OF HOURS. MOST LIKELY TIME FOR IMPACT FROM TSRA LOOKS TO BE LATE
AFTERNOON/EARLY EVENING /21Z-00Z/.

ON MON...SCTD TSTMS DURING THE AFTERNOON COULD IMPACT SOME
TERMINALS WITH LOCALLY MVFR CIGS/VSBYS. MORE ORGANIZED AREA OF
MVFR TO IFR CONDITIONS EXPECTED ON TUE AS LOW PRESSURE SLIDES EAST
ACROSS THE CAROLINAS. BY TUE NIGHT PRECIP WILL END...BUT SOME MVFR
VSBYS IN FOG POSSIBLE TUE NIGHT. HIGH PRES BUILDS IN ON WED AND
CONTINUES THROUGH THU BRING VFR CONDITIONS BOTH DAYS.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
SOUTHWEST FLOW INCREASES THIS AFTERNOON. BISHOPS HEAD AND
LEWISETTA ARE ALREADY IN SCA TERRITORY AND EXPECT THIS TO EXPAND
THROUGH THE AFTERNNOON. A FEW THUNDERSTORMS WITH GUSTY WINDS MAY
ALSO AFFECT THE WATERS EARLY THIS EVENING.

WINDS REMAINING BELOW SCA LEVELS FOR MOST OF MON THROUGH THU. A
CHANCE OF SHOWERS AND TSTMS FROM MON AFTERNOON THROUGH TUE NIGHT.
HIGH PRES BUILDS ACROSS THE WATERS ON WED AND CONTINUES THROUGH
THE END OF THE WEEK.
-- End Changed Discussion --

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
     ANZ530>533-535-536-538>542.
     SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ534-
     537-543.
-- End Changed Discussion --

&&

$$
SYNOPSIS...BAJ/SMZ
NEAR TERM...BPP/BAJ
SHORT TERM...SMZ
LONG TERM...SMZ
AVIATION...BPP/BAJ/SMZ
MARINE...BPP//BAJ/SMZ