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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 230129
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
929 PM EDT WED MAY 22 2013

.SYNOPSIS...
HIGH PRESSURE PERSISTING OVER THE ATLANTIC WITH WARM AND HUMID
CONDITIONS UNTIL A COLD FRONT THURSDAY NIGHT. AN UPPER TROUGH
WILL LINGER OVER THE AREA FRIDAY WITH HIGH PRESSURE BUILDING
THROUGH SATURDAY. A FRONTAL BOUNDARY STALLS OUT ACROSS THE MID-
ATLANTIC SUNDAY NIGHT THROUGH EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH THURSDAY/...
-- Changed Discussion --
CONVECTIVE ACTIVITY ON THE DECREASE ACRSS CWA ATTM. LOOKING AT
LINE OF SHRA/TSRA ROUGHLY ALONG I-81 THAT WILL SLOWLY MAKE ITS WAY
ACROSS THE CWA LATE TONIGHT. EXPECTING MAINLY SHOWERS WITH ISLTD
ELEVATED TSTM IN THIS ACTIVITY AS THE UPPER-LEVEL TROUGH
CONTINUES TO SLIDE CLOSER TO OUR AREA. MIN TEMPS TONIGHT WILL
RANGE FROM THE 50S IN THE MOUNTAINS TO THE LOWER AND MIDDLE 70S IN
DOWNTOWN WASHINGTON/BALTIMORE. AREAS THAT RECEIVED RAINFALL TODAY
WILL BE APT TO FOG-UP OVERNIGHT.
-- End Changed Discussion --

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
HGTS CONT TO DROP THU AS CDFNT APPROACHES. ALTHO INSTBY WL BE
LWR...SHEAR WL BE GREATER. THERE MAY BE TWO ROUNDS OF WX...FIRST
COMING MIDDAY WITH THE DISTURBANCE AND RIBBON OF INSTBY...AND THEN
SECOND NEARER THE CDFNT AND DIURNAL HEATING. HV RAISED POPS INTO
THE DEF RANGE RATHER QUICKLY...AND HOLDING IT THERE THRUT THE DAY.

CFP THU NGT. WL SCALE BACK POPS AND TRANSITION FM TSRA TO SHRA IN
THE EVNG. AFTER FROPA...ONLY LINGERING SHRA WL REMAIN.

FRIDAY...UPR TROUGH DRIFTS EAST OVER THE AREA WITH BACK EDGE OF
CLOUDS SLOW TO COME IN THE AFTERNOON. GUSTY NWLY FLOW FRIDAY
CONTINUES AS HIGH PRESSURE BUILDS THROUGH SATURDAY.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
SHORTWAVE FROM TN VLY ON SUNDAY NOW LOOKS TO EXPAND EAST ACROSS THE
SOUTHERN-CENTRAL MID-ATLANTIC. CONVERGENCE ALONG THIS BOUNDARY WOULD
SET OFF SHOWERS. PATTERN IS STALLED INTO MID NEXT WEEK...SO A
PROLONGED CLOUDY/RAINY PERIOD IS POSSIBLE. THIS WOULD RESULT IN
BELOW NORMAL TEMPS.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
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VFR-MVFR CONDITIONS AT ALL TERMINALS OVRNGHT.  THREAT FOR STORMS
CONT TIL CFP THURSDAY NIGHT. NWLY FLOW WITH GUSTS 25 TO POSSIBLY
30 KT WITH MID LEVEL CIGS FRIDAY. NWLY FLOW CONTINUES THROUGH
SATURDAY AS HIGH PRESSURE BUILDS.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
HIGH PRESSURE WILL REMAIN OVER THE ATLANTIC OCEAN OVERNIGHT. A
SOUTHERLY FLOW WILL CONTINUE OVER THE WATERS DURING THIS TIME. A
SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR PORTIONS OF THE WATERS
THROUGH TONIGHT. SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE
LATER THIS AFTERNOON AND EVENING. ANY THUNDERSTORMS THAT DO
DEVELOP WILL BE CAPABLE OF PRODUCING GUSTY WINDS AND HAIL.

SLY FLOW AHEAD OF A LATE THURSDAY NIGHT COLD FRONT. SCA EXPANDED
THROUGH THURSDAY. EXPECT AN EXTENSION THURSDAY NIGHT FOR PREFRONTAL
SLY FLOW...THEN NWLY FLOW AROUND 25 KT FRIDAY THROUGH SATURDAY AS
HIGH PRESSURE BUILDS.
-- End Changed Discussion --

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ530>534-
     536-537-539>543.
     SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM EDT THURSDAY FOR ANZ535-
     538.
-- End Changed Discussion --

&&

$$