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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 231401
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1001 AM EDT Wed May 23 2018

.SYNOPSIS...
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A cold front will push south through the area this afternoon.
High pressure will build eastward from the Great Lakes tonight,
eventually moving offshore by Friday. Moisture will increase
ahead of a low pressure system over the weekend into early next
week.
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&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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As of 930am, a cold front stretches from the central Chesapeake
Bay, to the south of Washington D.C., just north of
Fredericksburg, Virginia, and southwest into the central
Shenandoah Valley. This cold front will continue to move
southeast across our CWA the remainder of the day today. With
ample sunshine across the southern one- third of our CWA,
including southern Maryland, dewpoint temperatures in the
middle to upper 60s, and the cold front progressing
southeastward, we are anticipating a couple of scattered showers
and perhaps a thunderstorm or two this afternoon. It seems the
best time frame for this activity to develop is between Noon and
4 pm, although we can`t rule something developing a little
before and a little after this window. The area of interest
would be the central Shenandoah Valley, across the Virginia
Piedmont, and into southern Maryland. High temperatures will be
in the lower to mid 80s for most locations.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
The center of surface high pressure will be located over the
Great Lakes tonight, moving overhead by Thursday evening, then
off the Mid-Atlantic coast Friday. With ridging building aloft
as well, a respite from the recent unsettled weather will extend
through the end of the work week. Temperatures will be a little
above normal, with highs in the lower to mid 80s, and low
temperatures in the 50s to lower 60s.

Some moisture will begin to advance northward in the return
flow on the back side of the high by late Friday and Friday
night. Most of this advection will be focused on the Ohio
Valley, and while it`s not impossible a few showers could
develop over the Appalachians, have kept the forecast dry
through Friday night for now.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Southerly flow will continue advecting moist and
warm air over our region on Saturday as a Bermuda High is settled
over the North Atlantic. Temperatures will be between the low and
the mid 80s on Saturday with possible showers and thunderstorms in
the afternoon due to diurnal heating.

A low pressure system will be moving north from the Gulf coast and
along the southeastern states Sunday into Monday as Bermuda high
continues settled east of us. Winds will be turning more easterly as
moist air continues to be advected Sunday and Monday with
additional showers and thunderstorms.

A boundary will approach the area on Tuesday and settle over us into
Wednesday. This may trigger more showers and thunderstorms both
days.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
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A cold front will push southeastward the remainder of today.
Winds have become northwest at all terminals, except for CHO
terminal, where the front has not passed yet. We could encounter
a shower or thunderstorm near the CHO terminal during the early
to middle afternoon hours; elsewhere, dry conditions and VFR
conditions are expected at the other terminals. High pressure
will then build across the area through Friday. VFR conditions
and light winds are expected through the period.

VFR conditions likely Saturday with possible afternoon showers
and thunderstorms which may decrease the CIGS. Sunday and Monday
looks wetter with additional moisture over us, therefore more
showers and thunderstorms possible.
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&&

.MARINE...
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A cold front will push south across the waters of the Potomac
and Chesapeake Bay the rest of today. Winds will become
northwesterly behind the front. Peak winds will be around 15 kt
through the day, with a low probability for a few higher gusts.
High pressure will build across the waters tonight and Thursday
before moving offshore on Friday with light winds. Some of the
wider waters of the Bay may come close to SCA criteria Friday
night as southerly flow increases on the back side of the high.

Winds are expected to remain below SCA criteria from Saturday
into Monday, not anticipating an advisory for this period.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
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Tidal anomalies will continue to decrease this afternoon as
northwesterly winds develop behind a cold front. However, water
levels remain more elevated around DC given some freshwater
input, with the current high tide barely coming in below flood
stage. This situation may repeat itself during the morning high
tides the next couple days.
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&&

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

$$
SYNOPSIS...ADS/KLW
NEAR TERM...KLW
SHORT TERM...ADS/KLW
LONG TERM...IMR
AVIATION...IMR/KLW
MARINE...IMR/KLW
TIDES/COASTAL FLOODING...ADS/KLW