Area Forecast Discussion
Issued by NWS Sterling, VA

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FXUS61 KLWX 111420 AAA
AFDLWX

Area Forecast Discussion...UPDATED
National Weather Service Baltimore MD/Washington DC
1020 AM EDT Fri Aug 11 2017

.SYNOPSIS...
A warm front will lift north towards the region today. A cold
front will approach the region from the northwest Saturday, then
stall south of the area Sunday. A wave of low pressure may move
along the stalled front early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Mostly cloudy skies currently present except in northeast MD
where skies currently clear. NSSL WRF-ARW synthetic imagery
shows substantial breaks developing in the afternoon to help
destabilize atmosphere. Widespread showers and t-storms expected
especially west. 0-6km shear values around 35kt could support
some severe storms with mainly damaging winds. Activity could
linger well into the night especially along the bay.

Nocturnal decrease in precip is slowed by continued moist
southwesterly flow. Min temps upper 60s inland to around 70F
nearshore.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Cold front approaches Saturday warranting categorical PoPs across
much of the area. MLCAPE up to 1000 j/kg with chances for thunder
across the area. Dewpoints low 70s make for a much more humid day
than today.

Latest consensus of GFS/NAM/ECMWF is for the cold front to cross the
area Saturday night and cutoff PoPs by midnight. Cold front persists
south of the area through Sunday night with PoPs removed accordingly
through this time.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
We will be into the mid part of August during the extended part
of this forecast. The high heat remains at bay for next week -
80s for high temperatures all week. The upper level air flow
will be in a general zonal pattern. A short wave is expected to
push through the northeastern US Tuesday night. This will give
Tuesday/into the overnight hours the best potential time for
precipitation, although 30-40 PoP is all that can be warranted
for now.

Wednesday/Thursday look dry as weak ridging moves over the Mid
Atlantic.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
Rain with embedded scattered thunderstorms today and Saturday across
the DC metros before a cold front crosses Saturday night.

Tranquil/VFR behind the cold front Sunday.

VFR conditions expected Monday. There will be a potential for
degraded ceilings Tuesday.

&&

.MARINE...
South flow generally 15 knots today and Saturday ahead of a cold
front that crosses Saturday night. Will need to look out for SCA
NWly gusts Saturday night into Sunday.

Winds are expected to remain below SCA values Monday.
Showers/thunderstorms possible Tuesday.

&&

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

&&

$$
Update...LFR
Products...BAJ/WOODY!



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