Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

913
FXUS61 KLWX 110857
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
357 AM EST Thu Dec 11 2025

.SYNOPSIS...
A cold front attached to a clipper system will exit into the
Atlantic this morning. Another fast moving frontal system will
cross south of the region by Friday. A strengthening wave of
low pressure may impact the area Saturday night into Sunday
before Arctic high pressure moves in by early next week. This
ridge exits offshore by mid-week ahead of the next frontal
system.

&&

.NEAR TERM /THROUGH TONIGHT/...
The current synoptic pattern features a deep closed low along
the Ontario/Quebec border. This is part of a broader longwave
trough which extends down into the Great Lakes and northeastern
U.S. While the lead frontal system has exited into the western
Atlantic, a secondary surge is underway in response to the next
cold front. This is most evident in the uptick in west to
northwesterly winds with gusts rising to 20 to 25 mph, with 30
to 40 mph in the mountains. The well mixed boundary layer and
downsloping component to the flow has kept temperatures up
across areas east of the Alleghenies. 08Z/3 AM readings are
currently in the mid 30s to low 40s. However, temperatures
remain much colder across the Allegheny Front where snow showers
and windy conditions continue.

As of the writing of this discussion, Blizzard Warnings remain
in place until 10 AM across western sections of Garrett,
Pendleton, and Grant counties. Based on traffic cameras and
known observations, these warnings could be ended early and
converted to Winter Weather Advisories. Will continue to monitor
such trends over the next few hours. Otherwise, Winter Weather
Advisories also remain until 7 AM across eastern Garrett and
western Highland counties. For travelers that plan on crossing
the Alleghenies, ensure to stay winter weather prepared.

Mountain snow showers are expected to taper off through the
morning before the next round arrives by early Friday.
Otherwise, outside of the Alleghenies, expect increasing
sunshine heading toward the lunch hour. However, this does come
with another day of below average temperatures along with a
blustery northwesterly wind. Forecast highs will range from near
freezing to around 40 degrees, but with upper teens to 20s in
the mountains. Afternoon wind gusts are likely to top out around
25 to 30 mph, locally up to 40 mph across the Allegheny
ridgetops. Wind chills will fall into the single digits to mid
teens over the higher elevations.

The deep upper low initially over southwestern Quebec will slide
across New England toward the Canadian Maritimes late tonight.
However, in the wake, a broad west-northwesterly flow regime
sets up which comes with a series of embedded progressive
shortwaves. This steers additional mid/upper moisture toward the
area overnight. Clouds will thicken through the night with low
temperatures falling into the low/mid 20s, with teens across
mountain locales. Any precipitation chances should hold off
until daybreak Friday.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
As a series of waves dig across the Ohio Valley toward the
southern Mid-Atlantic, the accompanying frontal system will
track south of the region. Light snow spreads from the
Alleghenies toward the central Shenandoah Valley and to the I-64
corridor. Moisture is rather scant in this clipper pattern
which would overall limit the snow potential on Friday. Perhaps
an inch of snow is possible, locally a bit higher where
orographic lift augments totals. Heading toward the D.C. and
Baltimore metro areas, will maintain a 20 to 30 percent chance
for light snow. However, chances do appear better back toward
the mountains and well south of the metros.

With the frontal system tracking south of the local area,
gradients remain on the weaker side which favors lighter winds
than previous days. The forecast remains chilly with Friday`s
highs confined to the 30s (20s in the mountains). This is all
underneath mostly cloudy skies and the mentioned light snow
threat in spots. Heading into Friday night, the focus for any
wintry precipitation remains back along the Alleghenies in the
form of scattered snow showers. Forecast lows drop into the 20s
with light winds and continued cloud cover.

An active high-amplitude pattern continues into the weekend as
an upper low drops down from Manitoba toward the Great Lakes.
The parent upper low crosses far southern Ontario by Saturday
while trailing jet energy digs through the Midwest. This
positive-tilted trough shifts toward interior New England down
through the Ohio Valley on Saturday night. How this feature
evolves and tracks toward the Mid-Atlantic will eventually
dictate what snow threats will emerge starting late Saturday
night. At this point, a number of 00Z models show some
accumulations reaching areas east of the Blue Ridge into the
metros. Stay tuned but there does appear to be an increasing
signal of accumulating snows heading into early Sunday.

Ahead of this possible system, Saturday provides the mildest day
of the period. Mild is all relative given the forecast is still
around 5 degrees below average for mid-December. High
temperatures will range from the upper 30s to mid 40s, with mid
20s to mid 30s in the mountains. Skies turn overcast by
nightfall with low temperatures falling into the upper teens to
20s. Along the Alleghenies, single digits are more likely.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
The long term period will start out primarily dry as surface high
pressure moves over the mid-atlantic. The exception will be upslope
snow showers possible along the Alleghenies. As a cold airmass moves
overhead, well below temperatures can be expected Sunday and Monday.
High temperatures top out in the mid 30s each day with higher
elevations staying in the teens and 20s. Warmest wind chills on
Sunday will rise into the mid teens to lower 20s with the
Alleghenies staying in the negatives. Overnight low temperatures
will be in the teens to single digits.

Cold conditions continues to be the main theme on Monday as a
Canadian airmass moves over the east coast. High temperatures will
be in the 20s to low 30s with the Alleghenies staying in the teens.
Overnight low temperatures will drop into the teens. Dry conditions
continue Tuesday as temperatures begin to moderate. High
temperatures will be in the 30s to low 40s with overnight lows in
the 20s.

Precipitation chances increase Wednesday night as high pressure
shifts offshore and return flow ushers in increased moisture.
Additionally, a warm front tracking across the western portions of
the area will bring mountain rain showers earlier in the day. High
temperatures will be the warmest of the long term with highs in the
upper 30s to mid 40s. Overnight lows will be in the 30s across the
area.


&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
VFR conditions are expected through tonight behind the exiting
clipper system. A blustery west to northwesterly will impact all
terminals through sundown today with gusts to around 25 to 30
knots. Expect winds to diminish through the night as weak high
pressure builds in. The next system in the chain tracks south of
the local area on Friday. Some light snow accompanies this
feature, particularly down toward I-64 near KCHO. To the north,
increased cloud cover could yield some restrictions. Gradients
are weaker which keeps winds around 10 knots or less.

VFR conditions are likely on Saturday with west to southwesterly
wind gusts to around 10 to 15 knots. Clouds increase into the
evening and night ahead of the next weather maker. This system
could bring accumulating snow to the area by late Saturday
night. Regardless of winter threats, low ceilings should favor
restrictions overnight.

Low ceilings may lead to flight restrictions on Sunday with VFR
conditions returning by Sunday afternoon. Northwest winds gust 20 to
30 knots across the terminals Sunday before diminishing slowly
overnight. VFR conditions continue on monday with north west winds
gusting around 15 knots in the morning before becoming light.

&&

.MARINE...
Behind the exiting clipper system, a blustery west to
northwesterly wind will persist through much of the day. Small
Craft Advisories are in place across the waters through early
this evening given the expectation of 20 to 30 knot gusts. These
may need to be extended a few hours before winds drop off
overnight.

Weaker gradients set up over the waters on Friday and Saturday
which should keep the area advisory-free until later in the
weekend. Overall wind fields will largely be out of the west to
southwest.

Northwest winds gust 20 to 30 knots over the waters on Sunday in the
wake of a cold front. These could intensify through the second
half of Sunday into early Monday which may support gale
conditions. Small Craft Advisories are likely throughout the
day and through Monday morning. However, this may come with
gales over portions of the waters during this period. Winds
diminish as surface high pressure builds over the waters with
sub SCA criteria winds expected Monday afternoon.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 6 PM EST this evening for MDZ008.
     Blizzard Warning until 10 AM EST this morning for MDZ509.
     Winter Weather Advisory until 7 AM EST this morning for MDZ510.
VA...Winter Weather Advisory until 7 AM EST this morning for VAZ503.
WV...Blizzard Warning until 10 AM EST this morning for WVZ501-505.
MARINE...Small Craft Advisory until 6 PM EST this evening for
     ANZ530>543.

&&

$$

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