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000
FXUS61 KLWX 250130
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
930 PM EDT Mon Jul 24 2017

.SYNOPSIS...
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A cold front will pass through the area tonight. High pressure
will build into the Mid Atlantic Tuesday before moving offshore
Wednesday. Another cold front will approach the area Thursday
before passing through Friday into Friday night. High pressure
is expected to return for the weekend.
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&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
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Storms that developed in PA have outrun the cold front, which
looks to be pushing across the Alleghenies at 9 PM. The southern
extent of this line is currently moving across north central
MD. The 00Z IAD sounding shows 3000 J/kg of SBCAPE and about 40
kt of 0-6km shear, so the attendant severe threat (localized
damaging wind) is not a surprise. However, a mid level stable
layer is likely otherwise inhibiting storm development. Thus
it`s uncertain if any storms will develop along the outflow to
the south (affecting DC and areas to the southeast). While the
HRRR has been suggesting it`s possible, the 00Z run backed off.
Will have to watch radar, and have maintained chance POPs in the
forecast through 1 AM. After that time, the cold front will
likely have pushed through most of the CWA except perhaps
southern MD.

Afterwards some pretty nice weather for late July - the
climatologically hottest part of the year. Dewpoints will drop
into the lower to mid 60s by sunrise. Skies will be mostly clear
by morning. Lows west of I-95 will be in the mid to upper 60s,
lower 70s east.
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&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
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This will lead into a Tuesday with plenty of sunshine, dewpoints
in the lower 60s, and air temperatures reaching the lower to mid
80s.

Pleasant weather continues Tuesday night with lows in the mid
60s. Wednesday will see moisture begin to creep back into the
Mid Atlantic as high pressure moves offshore. Highs will reach
the lower to mid 80s. And with the return moisture lows will not
be as cool, falling to the upper 60s/lower 70s.
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&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Warm front lifts back north through the area early Thursday, which
will bring a return to the heat and humidity...as highs climb back
near 90F and dewpoints rise back into the 70s. Increasing chances
for showers and thunderstorms late Thursday into Friday as cold
front and its associated upper-level trough approach and then cross
the area.

High pressure builds into the area behind the front for the weekend
into early next week. Though, low pressure developing along the
front to our south could bring some precipitation back into SE
portions of the area Sunday. However, that is not the favored
solution at this point. Otherwise, remaining dry with highs in the
M80s and dewpoints in the 60s.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
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The thunderstorm threat will be exiting the Baltimore area
between 10 and 11 PM. While no storms are currently targeting
DCA, will leave VCTS mention in case a storm fires along the
outflow. Cold front should then cross within a few hours of
midnight with a wind shift to the northwest.

High pressure will affect the area Tuesday and Wednesday. Will
have to watch for low cloud potential with onshore flow early
Wednesday morning.

Showers and thunderstorms with brief flight restrictions are
possible ahead of a cold front mainly late Thursday into Friday.
Improving conditions into the weekend as high pressure builds into
the area.
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&&

.MARINE...
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Strong storms will affect northern portions of the Bay through
late evening. Cold front will then push through after midnight.
Some guidance hints at SCA potential in NW flow through Tuesday
morning. Will evaluate that threat over the next couple of
hours. Otherwise lighter winds through Wednesday with high
pressure.

A cold front will approach the waters Thursday into Thursday night
before passing through Friday. Showers and thunderstorms are
possible ahead of the front...especially late Thursday into Friday.
A Small Craft Advisory may be needed for portions of the waters
Thursday and Friday. Improving conditions into the weekend as high
pressure builds into the area.
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&&

.TIDES/COASTAL FLOODING...
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Straits Point may approach minor flood levels for the overnight
high tide cycle if water levels do not drop.
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&&

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

&&

$$

UPDATE...ADS
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