408
FXUS61 KLWX 050600
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
200 AM EDT Fri Sep 5 2025

.SYNOPSIS...
A cold front will continue to dissipate across the area today with
warm, dry, and breezy conditions expected. A much stronger cold
front will cross the area Saturday with another round of showers and
thunderstorms. Canadian high pressure will build in for the early
and middle part of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of early this morning, a cold front was dissipating over the
Appalachians. Some stratus accompanied this front, but any
precipitation has diminished. Patchy valley fog may become
locally dense west of the Blue Ridge Mountains through mid
morning before lifting.

Shortwave ridging will pivot over the Mid-Atlantic today.
Meanwhile, a strong cold front will track eastward across the
Ohio Valley. Some mid and high clouds may creep in as early as
this afternoon, but overall it will be mainly sunny. High
temperatures are expected to reach well into the 80s to around
90 for much of the area (70s at higher elevations).

Depending on the evolution of convection upstream, some showers
or thunderstorms in a weakening state may approach the
Alleghenies this evening. Should the storms be in a more
organized linear state as they approach, some residual gusty
winds would be possible, though the prospect for severe weather
(i.e. 58+ mph winds) looks low given loss of daytime
instability. Other than a few weakening showers west of I-81,
the night should be dry with lows in the 60s to lower 70s.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A pronounced upper jet/mid-level shortwave trough will deepen
and pivot northwest of the local area on Saturday. At the
surface, a strong cold front will cross from west to east. Cloud
cover may hamper heating and instability west of the Blue Ridge
and especially west of I-81, but further to the east
temperatures are likely to climb well into the 80s to near 90.
This heat, combined with dew points well into the 60s to near
70, will result in 1000-2000 J/kg MLCAPE despite weak mid-level
lapse rates. Flow in the 700-500 hPa layer will also increase
to 30-50 knots, resulting in adequate shear for organized
thunderstorms that develop as a result of convergence along the
strong front. The main threat appears to be damaging wind gusts
given unidirectional flow, steepening low-level lapse rates,
and weak mid-level lapse rates. There may be some brief training
element to storms as they approach the I-95 corridor late/into
the evening, but the recent very dry weather should preclude
most if not all flooding issues.

After the front crosses, northwest breezes will usher in a
fall-like airmass Saturday night through Sunday night. The
elevated winds and lingering clouds likely prevent full
radiational cooling Saturday night, keeping lows in the 50s to
lower 60s (upper 40s over the Appalachians). Highs Sunday look
to be about 10-15 degrees cooler than Saturday (70s, with 60s at
higher elevations). Lows Sunday night will have a chance to dip
a bit cooler given lighter winds and clearer skies, with 30s
possible for some of the high elevation valleys.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Another week where it feels more like early Fall compared to the end
of Summer. Synoptically, we`ll continue to monitor the progression
of a seasonably strong longwave trough as it pushes toward the
Canadian Maritimes and a large area of Canadian high pressure
dropping south from the northern Plains and Upper Midwest
Monday. This high pressure system will dominate the forecast
through much of next week as it works toward the northern Mid-
Atlantic Tuesday and off the northern New England coast
Wednesday into Thursday next week. Despite high pressure at the
surface, broad longwave troughing looks to persist across much
of the northeastern U.S. throughout the week and even into the
upcoming weekend. This is reflected in both the 6-10 and 8-14
day outlooks from the Climate Prediction Center which suggest
below average temperatures and below average precipitation
through the middle part of September.

Expect forecast high temperatures in the low to mid 70s
throughout the week for most with overnight lows in the upper
40s and low to mid 50s. Mountain locations will remain cooler
with highs in the upper 50s to mid 60s with overnight lows in
the 40s and low 50s. High elevation valley locations Monday,
Tuesday, and Wednesday mornings could see lows in the low to mid
30s given how dry the incoming airmass is.

Another cold front will cross the area Thursday before wedging high
pressure returns late next week. Rain chances look meager on both
ensemble and deterministic solutions furthering the concern for
potential drought expansion across the region; this is due largely
to a very dry August and start to September across the region.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
VFR conditions are expected to prevail through the valid TAF
period, and likely through the upcoming weekend. Some exceptions
will be in patchy fog/low clouds (mainly near CHO/MRB), and in
any SHRA/TSRA Sat PM; TS Sat could be accompanied by gusty
outflow winds. S/SW flow with daytime gusts of 15-20 kts is
expected through Sat, becoming NW Sat night-Sun.

VFR conditions look to prevail Monday through Thursday.
Northerly winds Monday will shift to the east and northeast
Tuesday into Wednesday at less than 10 kts.

&&

.MARINE...
Winds will become light out of the south to southwest through
this morning before increasing again this afternoon into this
evening. SCAs may be needed at times both in S/SW flow through
Saturday ahead of a cold front, and in NW flow behind the front
heading into Sunday. Winds turn northerly Sunday night as high
pressure builds toward the region. Otherwise, gusty t-storms
may affect the waters Saturday afternoon/evening.

SCA level northerly winds will likely linger into Monday morning
before decreasing Monday afternoon as high pressure builds in from
the Ohio River Valley. Onshore winds below sub-SCA levels are
expected Tuesday into Wednesday next week.

&&

.TIDES/COASTAL FLOODING...
Water levels likely decrease a bit today as a cold front
fizzles out, but minor flooding is still possible at a few
locations tonight as southerly flow strengthens again ahead of
the next front. This front will bring a wind shift Saturday
which will decrease water levels.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Coastal Flood Advisory until 8 AM EDT this morning for MDZ011.
     Coastal Flood Warning until 9 AM EDT this morning for MDZ014.
     Coastal Flood Advisory until 4 AM EDT early this morning for
     MDZ016-018.
     Coastal Flood Advisory from 6 AM to 11 AM EDT this morning for
     MDZ508.
VA...Coastal Flood Advisory until 4 AM EDT early this morning for
     VAZ057.
WV...None.
MARINE...Small Craft Advisory from 1 PM this afternoon to 3 AM EDT
     Saturday for ANZ530>534-537-539>543.
     Small Craft Advisory until 6 AM EDT early this morning for
     ANZ532>534-537-540>543.
     Small Craft Advisory from 1 PM this afternoon to 7 PM EDT this
     evening for ANZ535-536-538.

&&

$$

SYNOPSIS...EST
NEAR TERM...DHOF
SHORT TERM...DHOF
LONG TERM...EST
AVIATION...DHOF/EST
MARINE...DHOF/EST
TIDES/COASTAL FLOODING...LWX