521
FXUS61 KLWX 180740
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
240 AM EST Sun Jan 18 2026

.WHAT HAS CHANGED...
A Winter Weather Advisory has been issued for western Garrett
County until 7 AM. A Small Craft Advisory has been issued for
portions of the waters from late this morning through tonight.

&&

.KEY MESSAGES...
- 1) Low pressure will ride along a frontal boundary today. A
  mix of rain and snow will transition to all snow.

- 2) Very cold conditions are expected over the region Monday
  night through Tuesday night, with below normal temperatures
  continuing through the remainder of the week.

- 3) A wintry precipitation threat may re-emerge by
  late this week.

&&

.DISCUSSION...
KEY MESSAGE 1...Low pressure will ride along a frontal boundary today.
A mix of rain and snow will transition to all snow.

Temperature this morning (as of 07Z/2AM EST) were holding steady
or slowly rising over the lower elevations, generally in the
lower to middle 30s. Radar returns were beginning to fill in
aloft, with a few reports of precip reaching the ground along
the US-29 corridor. Meanwhile, a persistent band of moderately
heavy snow was oriented parallel to the ridges of western
Garrett County. This small but notable juxtaposition with the
terrain should persist until daybreak, with 2-3 inches total
expected. Elsewhere along and west of the Allegheny Front, a
coating to locally a couple of inches is possible, but minimal
spillover is anticipated (very low FROUDE numbers indicate
blocked flow). Snow should wind down as forcing and moisture
pivot east of the Appalachians after daybreak.

To the east, as fgen and upper jet support both increase over
the next several hours, an initial band of precip will develop
near the Blue Ridge Mountains and pivot east through about
midday. With marginal surface temps (especially southeast of
US-29), rain or a rain/snow mix is likely to start. As the
column cools, precip will change to snow. This highest snow
totals with this first band may focus between the Blue
Ridge/Catoctin Mountains and I-95 (near the US-15/US-29
corridors) where the best forcing overlaps slightly colder
temps. A lull is then expected as the initial forcing wanes.

Heading into this afternoon, a frontal wave of surface low
pressure develops in response to a shortwave exiting the
Southeast. This low will ride up and off the coast through this
evening, with precip on its western periphery likely filling
back in to about I-95. Incoming dry air from the west should
prevent much further westward expansion barring any unforeseen
significant changes with the low track/strength. This precip
should be mostly snow given cold air advection. Downslope drying
effects may be minimized given (1) a more northerly vs.
northwesterly component to the low-level wind, (2) its light
speed, and (3) distance from the terrain along the western shore
of the Chesapeake Bay (east of I-95 essentially). Therefore,
anticipate accumulating snow with this second wave mainly east
of I-95 this afternoon into early this evening.

Low pressure pulls away and precipitation ends. Given cold
temperatures and not a lot of wind especially this evening, any
residual moisture will likely refreeze on untreated surfaces.


KEY MESSAGE 2...Very cold conditions are expected over the region Monday
night through Tuesday night, with below normal temperatures
continuing through the remainder of the week.

An Arctic front will cross the Mid-Atlantic Wednesday, sending
temperatures tumbling to some of their coldest values so far
this season come Tuesday morning. The front will come through
largely dry, though some mountain snow showers are possible as
it crosses the Appalachians. Temperatures falling into the teens
and single digits combined with blustery northwest winds Monday
night into Tuesday morning will result in wind chills in the
single digits are either side of 0, with negative teens and 20s
over the Alleghenies.

Following the front, Tuesday is going to be the coldest day of
the forecast period by far. Would not expect high temperatures
to exceed 30 degrees anywhere, with teens and 20s in the
mountains. It will be particularly cold Tuesday night as well
with lows in the single digits to teens. While not as windy,
there will still be just enough to keep wind chills in the
single digits for most (negatives in the mountains).

A slight warmup is expected Wednesday into Thursday, with
temperatures closer to average by Thursday afternoon.

KEY MESSAGE 3...A wintry precipitation threat may re-emerge by
late this week.

A cold front looks to track across the area sometime Thursday
afternoon/evening. This could bring a rain or a wintry mix to
parts of the area, though precip chances overall are low at 15
to 20 percent due to large discrepancies in the timing of the
front. Cold air surges in behind the front to close the week.

Below normal temperatures will return for Friday into Saturday as
high pressure returns to the region. Another potentially potent
wave is hinted at by a lot of guidance (with ensemble support)
later next weekend that bears monitoring.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Wintry precipitation and rapidly falling ceilings are expected
especially for the metro TAF sites this morning. A brief period
of -SN is possible at KMRB until roughly 12Z-13Z, with some -RA
mixing in near KCHO during the same time. For the metros, a
start as -RA or -RASN is most likely before transitioning to
mostly of all -SN between 11Z-13Z. This first band will pivot to
the east between 14Z-16Z. The lowest VSBY is most likely near
KBWI/KMTN where 1 SM or less is possible; this is also where
potentially plowable accums are most favored, though that
potential does exist at KDCA and especially KIAD as well. Winds
will generally be light out of the N/NW during this period.

Once the first band moves east, winds increase a bit with a few
gusts of 15 to perhaps 20 kts possible heading into the
afternoon. Low pressure developing along the coast may throw
some snow back toward the I-95 TAF sites (KDCA and especially
KBWI/KMTN) from roughly 19Z-01Z. Winds become lighter tonight
after dark as precip exits, then turn S by Mon AM.

VFR conditions are expected Mon-Tue with blustery W/NW winds.
Gusts of 25-30 kts are most likely once winds shift back to the
W/NW Mon afternoon. Gusts will slacken a bit Mon night, but
15-25 kt gusts are possible during the day Tue.

VFR is expected to prevail Wed-Thu with S winds Wed and W winds
Thu gusting 15-25 kts during the day. There are some pieces of
guidance that draw precip into the region Thu, however.

&&

.MARINE...
Northwest winds will increase after a band of rain/snow moves
across the waters later this morning into this afternoon, and
likely remain elevated into the night as low pressure passes
offshore with additional rain/snow possible this afternoon into
the evening. Winds shift briefly to southerly Monday morning
ahead of a reinforcing Arctic front before becoming west to
northwest Monday afternoon through Tuesday. Gusts of 20 to 30
knots are most likely from roughly midday Monday through Monday
evening, with a general decrease in winds through Tuesday night.

Winds shift back to the south Wednesday, then west and northwest
Thursday with SCAs possible both ahead of and behind a front
that could bring some precip near the waters Thursday.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Winter Weather Advisory until 6 PM EST this evening for DCZ001.
MD...Winter Weather Advisory until 6 PM EST this evening for MDZ005-
     006-008-011-013-014-503>508.
     Winter Weather Advisory until 7 AM EST this morning for MDZ509.
VA...Winter Weather Advisory until 6 PM EST this evening for VAZ053-
     054-506-526-527.
WV...None.
MARINE...Small Craft Advisory from 10 AM this morning to 4 AM EST
     Monday for ANZ530>534-537-539>541-543.

&&

$$

DISCUSSION...DHOF/CJL
AVIATION...DHOF/CJL
MARINE...DHOF/CJL

NWS LWX Office Area Forecast Discussion