959
FXUS61 KLWX 182013
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
313 PM EST Tue Nov 18 2025

.SYNOPSIS...
Rain chances return this afternoon and evening as an area of low
pressure traverses a stalled front draped south of the Mid-Atlantic
region. Drier weather conditions are expected Wednesday into
Thursday with another wave of low pressure set to approach from the
mid-Mississippi and Ohio River Valleys Friday. Rain chances will
continue through Saturday with high pressure returning Sunday into
early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
The latest multi-channel water vapor imagery shows a closed low
spinning near the Illinois-Wisconsin border. At the same time,
there is plenty of mid/upper moisture being lofted downstream
into the lower Ohio Valley and Mid-Atlantic region. Although
this locally saturated the mid/upper troposphere, the latest
local aircraft soundings show significant dry air from 700-mb
down to the surface. This will certainly have consequences in
terms of initial precipitation efficiency.

At the surface, recent frontal/pressure analysis depicts broad
high pressure along the Mid-Atlantic to Carolina coast. Farther
upstream, a wave of low pressure is sweeping through central
Missouri with the warm front straddling southern Illinois into
western Kentucky. This progressive system is slated to race
toward the east during the next 6 to 12 hours.

Broad ascent within the air mass downstream will continue to
foster the develop of widespread rain showers. This is already
evident on the regional mosaic radar imagery as well as the
local WSR-88D. It is evident the lead activity is at least 2 to
3 hours ahead of most of the high-resolution models. While
impressive in its radar signature given over 40 dBZ on the
lowest tilt, the enhancement is likely owing to bright banding
effects. Current dew point depressions run between 15 to 25
degrees which suggest plenty of virga is being observed.

As the lower 300-mb of the troposphere continue to moisten, a
light to locally moderate rain will overspread the entire area
just after dark. The fast moving nature of this system should
hold the duration of showers to around 6 to 8 hours. While
temperatures will be falling from the mid/upper 40s as
precipitation falls, the only true threat for a wintry mix would
be over eastern Garrett and western Allegany/Mineral counties. A
pocket of cooler air across valley locations in these counties
may lower temperatures enough to allow for a brief period of
light snow and/or freezing rain. The most likely timeframe would
be 6 to 10 PM which could impact travelers on local roads. As
such, a Special Weather Statement continues for this low-end
threat.

After seeing around a quarter to half inch of rainfall (closer
to inch along the Alleghenies), conditions dry out from west to
east overnight. With the frontal system passing by to the south,
local winds largely stay out of the east to southeast. This
onshore component to the winds helps keep low temperatures in
the upper 30s to low 40s, with mid 30s from the Shenandoah
Valley westward. Light winds coupled with saturated grounds will
likely yield some patchy fog, locally dense in some spots. This
also comes with extensive low clouds which helps keep low
temperatures up from previous nights.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
To start off Wednesday, low clouds and patchy fog are likely to
dominant a bulk of the area during the early/mid morning hours.
A wedge setup develops with the cold front settling over the
Carolinas and high pressure building across the interior
northeastern U.S. This yields a prevailing northerly wind
underneath cloudy skies, although some sunshine could mix in
closer the I-64 corridor. The resultant cold advection pattern
should hold high temperatures in the upper 40s to low 50s from
U.S. 50 northward. Off to the south, some mid 50s to low 60s are
possible across the central Virginia Piedmont toward Albemarle
and Nelson counties. These locations are the most likely spots
to see some sun mixing in. Expect plenty of clouds to linger
into the evening and night. Forecast lows fall into the
mid/upper 30s, with spotty low 40s along urbanized portions of
I-95.

Global models show gradual height rises into Thursday as the
northern extent of a ridge centered over the Gulf of America
grazes the Mid-Atlantic states. However, like preceding days,
cloud cover will be widespread in nature. Despite the low-level
wind shift over to south to southeasterly, models show quite a
bit of moistening of the mid/upper column. This is in response
to a thick cirrus shield spreading downstream from an area of
showers and thunderstorms over the Arklatex region. Any showers
should not reach the Allegheny Front until late Thursday.
Forecast highs on Thursday will be in the upper 40s to 50s,
coolest along the Mason-Dixon Line and across the mountains. At
night, light warm advection coupled with cloudy skies is
forecast to keep lows in the low/mid 40s.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Rain chances return after a brief reprieve during the midweek
period. Synoptically, we remain in a split flow jet pattern with the
northern stream remaining much more amplified compared to the
southern stream. This will in turn drive our local weather pattern
through the weekend into early next week.

The next trough of low pressure looks to work across the Hudson
Bay/northern Great Lakes into eastern Canada/New England Friday into
Saturday. Meanwhile, southern stream low pressure will work across
the mid-Mississippi and the lower Ohio River Valleys into the VA/NC
Piedmont during the same aforementioned timeframe. Both of these
systems will deliver another round of widespread light to perhaps
moderate rain to the region Friday into Saturday. Despite the rain
chances and added cloud cover, temperatures look to warm during the
late week period. Highs Friday will push into the upper 50s and low
60s (mid to upper 40s mountains) due to southerly flow.
Mid to upper 50s (upper 40s mountains) are expected Saturday as
winds change back to the west to northwest direction with a cold
front pushing through. Overnight lows Friday night will remain in
the mid to upper 40s and low 50s with mid 30s and low 40s Saturday.

Cooler conditions look to return late Saturday night into Sunday as
a cold front pushes the southern stream low pressure offshore.
Meanwhile, the northern stream low pressure will continue off the
Canadian Maritimes late Friday into Saturday. Still some uncertainty
remains in regards to the placement of the northern and southern
stream low pressure systems, along with their associated fronts
which would dictate how quickly things dry out for the back
half of the weekend. Overall current 06z/12z
deterministic/ensemble guidance suggests rain chances lingering
through Saturday morning with drier conditions in the afternoon
and evening as high pressure returns.

Sunshine makes its way back into the forecast Sunday as high
pressure settles over the central Appalachian region. The high
will slide off the VA/NC coast Monday with another front set to
approach from the Ohio River Valley by the middle part of next
week. Upslope rain and snow showers will likely return to the
mountains Tuesday with shower chances increasing to the east
Wednesday and Thursday next week as the front stalls to the
south.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
A frontal system approaching from the Upper Great Lakes will
gradually introduce lengthy restrictions to the area. Initial
winds have been relatively light and somewhat variable in
nature. While showers have moved in earlier than expected at
KCHO, other terminals should see such activity move in just
after dark. Winds turn more southeasterly as this occurs with
any sub-VFR conditions holding off until the mid/late evening.
As rainfall decreases in intensity, ceilings should further
lower to IFR during the second half of the night. The light
onshore flow coupled with saturated grounds will foster the
development of some patchy fog. At this time, have not lowered
visibilities below 4 SM.

While the shield of rainfall exits before daybreak, IFR to MVFR
ceilings are expected to dominate much of Wednesday. This is in
response to a wedge setup with high pressure to the north and
persistent northerly winds funneling into the area. The best
chance for any breaks in the overcast would be at KCHO. Heading
into Wednesday night, skies remain mostly cloudy which aviation
guidance favors more sub-VFR ceilings. Thick cloud cover
continues into Thursday with winds shifting to southeasterly. A
number of models favor MVFR ceilings through the day before rain
arrives overnight.

Temporary restrictions are possible at times Friday and Saturday
with rain showers around. Expect periods of MVFR with perhaps
pockets of IFR depending upon the intensity of rainfall across the
region. Overall light to moderate rain is expected as low pressure
and its associated fronts pass through the area. South to
southwest winds are expected to gusts 15 to 25 kts with winds
switching back to the north and northwest Saturday into Sunday.
Gusts this weekend will remain between 5 to 15 kts.

&&

.MARINE...
Gradients have weakened over the past 12 to 24 hours.
Consequently, the prevailing south to southeasterly winds have
largely seen gusts topping out around 10 to 15 knots. A frontal
system approaches from the west this evening before passing by
to the south early Wednesday. As the cold front sags southward
into the Carolinas and high pressure builds over the interior
Northeast, northerly winds begin to strength and may channel.
Small Craft Advisories could be needed early Wednesday evening
into portions of the night, especially across wider portions of
the Chesapeake Bay. Thursday is the transition period as the
next system churns across the Missouri Valley. Marine wind gusts
during this time will mainly stay around 10 knots or less.

Small Craft Advisories may be needed for portions of the waters
Friday into Saturday. Some south to southwesterly channeling is
possible Friday with breezy north to northwest winds in the wake of
the cold front Saturday. Sub-SCA level winds are expected Sunday
into Monday next week with high pressure nearby.

&&

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

&&

$$

SYNOPSIS...EST
NEAR TERM...BRO
SHORT TERM...BRO
LONG TERM...EST
AVIATION...BRO/EST
MARINE...BRO/EST