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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 161901
AFDLWX

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

.SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE WILL REMAIN OFF THE EASTERN SEABOARD...AS A TROUGH
OF LOW PRESSURE MOVES THROUGH THIS AFTERNOON AND EVENING. A WEAK
COLD FRONT WILL APPROACH FROM THE NORTH ON MONDAY...BECOMING
STATIONARY OVER THE MID-ATLANTIC 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.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH MONDAY/...
-- Changed Discussion --
HIGH PRESSURE WAS LOCATED OVER THE WESTERN ATLANTIC THIS AFTERNOON.
SOUTHERLY FLOW HAS RETURNED TO THE MID-ATLANTIC WHICH HAS ALLOWED
DEWPOINTS TO INCREASE INTO THE LOWER TO MID 60S AS AFTERNOON
TEMPERATURES WERE WARMING INTO THE LOWER TO MID 80S.

DESPITE INCREASE IN DEWPOINTS...INSTABILITY REMAINS RELATIVELY WEAK
THIS AFTERNOON PER CAPE/LAPSE RATE FIELDS FROM THE SPC MESOANALYSIS
PAGE. THIS IS IN PART DUE TO BROKEN MID LEVEL CLOUDS THE CWA HAS
EXPERIENCED MUCH OF THE DAY WHICH HAS INHIBITED DESTABILIZATION. AS
SUCH...WHILE A SHORTWAVE WILL MOVE ACROSS THE CWA LATER THIS
AFTERNOON/EVENING WITH SCATTERED TO NUMEROUS SHOWERS AND A FEW
THUNDERSTORMS...THE SEVERE WEATHER RISK MAY WIND UP BEING ON THE
LOW/ISOLATED SIDE.

WRF-ARW HAS ALSO BACKED OFF ON THE ORGANIZED CONVECTION IDEA WHICH
IT PORTRAYED EARLIER...AS HAS THE HRRR. BOTH MODELS INDICATE THAT
THE STRONGEST ACTIVITY MAY WIND UP BEING ACROSS THE SOUTHERN PORTION
OF THE CWA OR PERHAPS MORE INTO SOUTHERN VIRGINIA ON THE SOUTHERN
FRINGE OF THE BROKEN CLOUD DECK. FORECAST WILL BE REFINED TO
HIGHLIGHT THIS AREA SUSCEPTIBLE TO THE ISOLATED SEVERE RISK FOR
LOCALLY DAMAGING WIND GUSTS DURING THE LATE AFTERNOON/EVENING.

CONVECTION MAY CONTINUE WELL INTO THE EVENING ACROSS THE SOUTHERN
REACHES OF THE CWA AS MODELS SHOW A CONVERGENCE AREA/TROUGH
LINGERING ACROSS THIS AREA OVERNIGHT.

MONDAY...A COLD FRONT IS FORECAST TO MOVE INTO THE CWA FROM THE
NORTH. DURING PEAK HEATING...THE BOUNDARY LOOKS TO BE LOCATED ACROSS
THE SOUTHERN PORTION OF THE CWA AND THIS IS WHERE THE HIGHEST
COVERAGE OF CONVECTION MAY OCCUR. BUT WITH THE FRONT NEARBY AND
AFTERNOON INSTABILITY WILL KEEP A CHANCE OF AFTERNOON THUNDERSTORMS
FURTHER NORTH TOWARD THE MASON DIXON LINE.

BIAS CORRECTED MAV/MET WERE CLOSE AND BLENDED FOR MINIMA
TONIGHT...THEN LEANED TOWARD THE WARMER MAV ON MONDAY.
-- End Changed Discussion --

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
-- Changed Discussion --
THERE IS STILL SOME DISAGREEMENT REGARDING THE POSITION OF THE
FRONTAL BOUNDARY MONDAY NIGHT INTO TUESDAY. THE FRONT COULD BE
STALLED OUT ACROSS THE SOUTHERN PORTION OF THE CWA DURING THIS
TIME...OR COULD BE FURTHER SOUTH TOWARD THE VIRGINIA/NORTH CAROLINA
BORDER. FAVOR THE FORMER SOLUTION BUT EITHER WAY MODELS SHOW MID-
LEVEL SHORTWAVE ENERGY MOVING THROUGH IN WESTERLIES...AND WILL
CONTINUE A CHANCE OF SHOWERS AND THUNDERSTORMS DURING THIS TIME
HITTING THE SOUTHERN PORTION OF THE CWA WITH THE HIGHEST POPS.
-- End Changed Discussion --

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
-- Changed Discussion --
HIGH PRESSURE SHOULD HELP TO PUSH THE FRONT FURTHER SOUTH ON
WEDNESDAY...AND SHOULD BE IN CONTROL FOR THE REST OF THE WEEK AND
POSSIBLY INTO THE WEEKEND.
-- End Changed Discussion --

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
SHORTWAVE MOVES ACROSS THE AREA THIS EVENING SUPPORTING A FEW
SHOWERS AND POSSIBLY A THUNDERSTORM. HAVE BACKED OFF ON PREVAILING
TSRA IN 18Z TAFS AS INSTABILITY IS WEAK...ONLY INCLUDING VCTS
DURING THE MOST LIKELY TIME FOR A TSRA. TROUGH MOVES THROUGH THE
AREA TONIGHT. WILL CONTINUE WITH A CHANCE OF MAINLY
AFTERNOON/EVENING THUNDERSTORMS MONDAY AND TUESDAY UNTIL A COLD
FRONT IS PUSHED SOUTH OF THE AREA BY WEDNESDAY.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
S/SW WINDS CONTINUE TO INCREASE EARLY THIS AFTERNOON...SUPPORTIVE OF
SCA FOR 20 KT. WINDS SHOULD DIMINISH NEAR OR JUST BEFORE SUNSET.
WILL ALSO HAVE TO KEEP AN EYE ON SHOWERS AND THUNDERSTORMS AS THEY
MAY BE CAPABLE OF PRODUCING GUSTS THAT WOULD REQUIRE SMW/S THIS
EVENING. FRONTAL BOUNDARY OVER THE AREA MONDAY-TUESDAY WILL KEEP A
CHANCE OF THUNDERSTORMS OVER THE WATERS...THEN HIGH PRESSURE BUILDS
IN FOR WEDNESDAY.
-- 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>543.
-- End Changed Discussion --

&&

$$
BPP