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FXUS61 KLWX 210758
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
358 AM EDT Thu Sep 21 2017

.SYNOPSIS...High pressure both at the surface and aloft will build overhead
through the weekend. Hurricane Maria may approach the mid-
Atlantic coast middle of next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

Early this morning, Jose continues to meander off the coast of New
England, well to our east, while a ridge of high pressure is
building over the midwest aloft. At the surface, the high pressure
ridge extends along the Appalachians. The only fly in the ointment
is the trough which brought showers and thunderstorms to western
Virginia yesterday - this system remains nearby, but is slowly
sinking south. Its influence  may still bring a stray shower to the
far southwestern corner of the CWA this afternoon, but odds look
considerably less than yesterday, so have just included some slight
chance POPS for now. Otherwise, patchy fog this morning should break
for another mostly sunny and warm day, with another clear to partly
cloudy night with more patchy fog. The air mass is drier than it was
24 hours ago, and we have not had significant rain in a couple
weeks, so dense fog is not going to be as easy to come by as it
might otherwise be. However, a few spots may drop to 1/4 mile early
this morning and again late tonight, but not up to Dense Fog
Advisory calibre. Highs today will be well into the 80s once again,
with lows tonight in the 50s and 60s once again. Winds will be light.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...

High pressure ridge at the surface will remain more or less
stationary over the Appalachians through Saturday night. Aloft,
ridge of high pressure centered over the Midwest will continue to
extend its influence across our region, while Jose will continue to
meander over the northwest Atlantic near New England. End result
will be continued warm and dry weather, with the only real weather
concern being extent and coverage of patchy fog each morning. Highs
will be well into the 80s Friday and Saturday with lows in the 50s
and 60s. Winds will be light.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...

Strong ridge of high pressure will remain in place through at
least Sun and likely beyond albeit weakening. With regards to
the track forecast of Hurricane Maria, global models show Maria
having a similar track to Jose tracking a little west of 70W.
Please consult NHC forecasts for more info on Hurricane Maria.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...

Main concern through the next several days is patchy late night and
early morning fog, mainly at MRB and CHO. Vis could drop briefly to
IFR at either or both sites each of the next three mornings. An MVFR
restriction is not out of the question at the other terminals
(except DCA). Otherwise, VFR with light winds should prevail
through Saturday night thanks to high pressure.

No sig wx wx expected through Mon.

&&

.MARINE...

High pressure will provide dry weather with sub-SCA winds through
Saturday night.

Global models show winds strengthening on Tue as pressure
gradient tightens as Hurricane Maria gets closer to the mid-Atlc
coast middle of next week. For now, it appears small craft
advisories are possible.

&&

.TIDES/COASTAL FLOODING...

Minor coastal flooding will continue at most of the sites over
the next several days.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Coastal Flood Advisory until midnight EDT tonight for DCZ001.
MD...Coastal Flood Advisory until 5 PM EDT this afternoon for
     MDZ018.
     Coastal Flood Advisory until 9 AM EDT this morning for MDZ011.
     Coastal Flood Advisory until 9 PM EDT this evening for MDZ014.
     Coastal Flood Advisory until 7 AM EDT this morning for MDZ016.
     Coastal Flood Warning until 6 AM EDT early this morning for
     MDZ017.
     Coastal Flood Advisory until 7 PM EDT this evening for MDZ017.
VA...Coastal Flood Advisory until 7 AM EDT this morning for VAZ057.
     Coastal Flood Advisory until midnight EDT tonight for VAZ054.
WV...None.
MARINE...None.

&&

$$
SYNOPSIS...BJL/LFR
NEAR TERM...RCM
SHORT TERM...RCM
LONG TERM...LFR
AVIATION...RCM/LFR
MARINE...RCM
TIDES/COASTAL FLOODING...LFR