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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 202354
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
754 PM EDT MON MAY 20 2013

.SYNOPSIS...
HIGH PRESSURE OVER THE ATLANTIC WILL PROVIDE A SOUTHERLY FLOW FOR
TUESDAY AND WEDNESDAY...BRINGING WARM AND HUMID CONDITIONS.
MEANWHILE...AND UPPER LEVEL DISTURBANCE WILL CROSS THE REGION. A
COLD FRONT WILL PASS THROUGH THE AREA THURSDAY AFTERNOON AND
EVENING. COOLER CONDITIONS WILL RETURN FOR NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TUESDAY/...

-- Changed Discussion --
ALTHO NOT QUITE AS WARM...WINDWISE IT FEELS SOMEWHAT LK MID-SUMMER
GIVEN HOW LGT THE WIND FIELD IS. CELLS WHICH PRODUCE ISOLD FLDG IN
AUGUSTA CO. IN LATE AFTN ARE BEGINNING TO WEAKEN.

ONCE DAYTIME HEATING WANES...SHRA/TSRA CVRG SHUD DIMINISH. AM
RUNNING WITH A DRY FCST OVNGT. ITS PSBL THAT THERE MAY BE A STRAY
STORM OR TWO...BUT CANNOT PINPOINT WHERE...AND WUD RATHER NOT
BLANKET LOW POPS OVER A LARGE AREA.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
-- Changed Discussion --
MID-ATLANTIC WILL BE ON THE WARM SIDE OF THINGS DURING MID-WEEK.
THIS WILL ALLOW FOR A WARM UP TUESDAY-WEDNESDAY...WITH HIGHS IN
THE MID 80S. IF THERE IS MORE SUNSHINE...TEMPS COULD REACH UPPER
80S IN SOME LOCATIONS.

THERE WL BE TRRN CIRCULATIONS AND DIURNAL HEATING BNDRYS. HV CHC
POPS CENTERED UPON TIME OF PEAK HTG TUE AFTN. AM TAKING THAT ROUND
EWD IN THE EVNG INVOF H5 AXIS.

THE MID LVL RDG AXIS BREAKS DOWN WED WHICH WL PROVIDE ITS OWN TSRA
SUPPORT. WED AFTN POPS SEEM ADEQUATE IN THE 30-40 PCT RANGE...BUT
HV INCREASE EVNG CVRG AS HGTS FALL. NWRN CORNER OF CWFA TOUCHING
SPC DAY 3 SLGT RISK...AND ISOL SVR CRVG TO APPROX THE BLURDG IN
CONJUNCTION WITH THIS THREAT.
-- End Changed Discussion --

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
SLIGHT HEIGHT FALLS ARE FORECAST TOWARD THE END OF THE WEEK AS AN
UPPER TROUGH APPROACHES...IN TANDEM WITH A COLD FRONT. THERE IS SOME
QUESTION REGARDING TIMING OF THE FROPA...LATEST GUIDANCE SUGGESTING
LATE THURSDAY INTO EARLY FRIDAY. DUE TO UNCERTAINTY HAVE CHANCE POPS
IN THE THURSDAY THROUGH FRIDAY TIME FRAME...AND WE CAN FINE TUNE THE
TIMING AS WE GET CLOSER.

THERE IS GOOD AGREEMENT THAT THE FRONT WILL HAVE MOVED THROUGH THE
AREA BY THE WEEKEND...FAVORING A COOLER/DRIER AIR MASS. FORECAST
REFLECTS MOSTLY CLEAR SKIES AND TEMPERATURES NEAR CLIMATOLOGY.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...

-- Changed Discussion --
VFR CONDS PREVAIL AT ALL SITES. FOG MAY FORM AFTR MDNGT..AND HV
3SM IN SVRL OF THE TAFS..BUT GIVEN TEMPS AT SVRL SITES HAD A POST
5 PM MAX AM UNCERTAIN THIS LATE DAY WARMTH WAS FIGURED INTO THE MDLS.

EXPECT FOG/STRATUS EARLY TUESDAY AS LOW LEVEL MOISTURE REMAINS.
ONCE THIS MSTR BURNS OFF...VFR EXPECTED TO PREVAIL THE BALANCE OF
TUESDAY. CHANCE OF THUNDERSTORMS RETURNS IN THE AFTN...BUT CVRG
ISSUES REDUCE CONFIDENCE IF AIRFIELDS WL BE IMPACTED. A REPEAT
PERFORMANCE POSSIBLE WED...AND AGAIN THU. GREATEST CVRG ASSOCD
WITH CFP LT THU.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
SLY WNDS 10-15 KT OVRNGT.

SLY WINDS ARE EXPECTED TUE-WED UNTIL A COLD FRONT MOVES THROUGH
THU SWITCHING WINDS TO THE NORTHWEST. THERES A DAILY TSRA RISK...
SPCLY IN THE AFTN/EVE.

SOUTHERLY CHANNELLING UP THE BAY COULD BRING MARGINAL SCA
CONDITIONS...PARTICULARLY DURING THE LATE AFTERNOON/EVENINGS.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
TIDAL ANOMALIES REMAIN NEAR NORMAL. WILL HAVE TO WATCH SOUTHERLY
FLOW DURING THE MID-WEEK AS IT MAY SUPPORT AN INCREASE IN
DEPARTURES AGAIN.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.

&&

$$
UPDATE...WOODY!
PRVS...HTS