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000
FXUS61 KLWX 180135
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
935 PM EDT Wed Apr 17 2024

.SYNOPSIS...
A stationary front will slowly lift northward as a warm front
tonight, eventually pulling north of the region by early
Thursday. A weak cold front will track through on Thursday
before a stronger cold front arrives on Saturday. High pressure
returns on Sunday and into early next week.

&&

.NEAR TERM /THROUGH THURSDAY/...
EVENING UPDATE...
The line of showers and thunderstorms progged to arrive tonight
has been moving a bit faster than anticipated, now moving into
far western Maryland. Currently it seems the line has begun to
weaken as it approaches the mountains, consistent with earlier
thinking, but will continue to monitor as the cold front moves
through.

Previous discussion follows...
Latest CAMs suggest that line will reach western MD around 02Z.
Expect the line of convection over OH to weaken rapidly into
showers as it enters Maryland tonight as it will be arriving
around or after midnight.

Overnight, areas of low clouds and/or fog are likely
particularly across north central MD.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
Warm front lifts into PA Thu followed by a weak cold front.
Guidance shows a stable air mass and plenty of mid-level dry air
to prevent convection, so only a windshift is expected.

Next cold front will cross the area Friday with showers
expected. Air mass looks stable to prevent thunderstorms.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A cold front will be draped further south early Saturday, with
limited moisture availability but winds will be gusting 20 to
25 knots, especially along and west of the Blue Ridge Mountains.
Highs will be in the 60s to low 60s for much of the area aside
from the mountains, where mid 50s will be more common. Slightly
cooler weather returns Sunday with continued dry conditions
across the area with winds diminishing.

By the start of the workweek, a low pressure system to the south
will continue to nudge eastward. A few light showers will be
possible, mainly across the southernmost tier counties of our area.
Temperatures will begin to climb back into the upper 60s to near 70
Monday and Tuesday. Renewed shower chances increase as a shortwave
moves nearby from the Great Lakes region. Warming conditions will
continue into midweek.

&&

.AVIATION /01Z THURSDAY THROUGH MONDAY/...
Some showers and/or t-storms are expected tonight mainly across
northern MD. They are likely to stay away from the main
terminals, except MRB. Guidance consistently brings in low
clouds to BWI and MTN tonight, which have already made it to
MTN. Additionally there were some hints of low clouds making it
as far south/west as IAD and DCA, but with lower confidence.
Hinted at low clouds for IAD and DCA in the TAF for now.

Wind shift tomorrow to NW behind a cold front, but remaining
dry. Some guidance tries to bring in low clouds around or after
06z tomorrow night for our northeastern terminals, which is
right at the end of the 30 hr TAF period, so included some
lowering cigs (but not quite MVFR) at the end of the TAF for
now.

VFR conditions are expected Saturday into Sunday, with gusty WNW
winds expected on Saturday before dissipating by Sunday.

&&

.MARINE...
Showers possible across the northern waters tonight and Fri.
Marginal SCA gusts are possible Thu.

SCA conditions are possible Saturday into Saturday night before
winds weaken into Sunday. No other marine hazards are expected for
the weekend.

&&

.TIDES/COASTAL FLOODING...
While some action stages may be reached through Thursday night
(anomalies 1-1.5 feet above normal), the greater water level rises
and potential for minor flooding will be toward Friday and Friday
night as onshore or southerly flow develops ahead of a low pressure
system.

&&

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

&&

$$

SYNOPSIS...LFR
NEAR TERM...LFR
SHORT TERM...LFR/CAS
LONG TERM...ADM
AVIATION...LFR/ADM/CAS
MARINE...LFR/ADM
TIDES/COASTAL FLOODING...LWX