Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

939
FXUS61 KLWX 221514
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1014 AM EST Sun Feb 22 2026

.WHAT HAS CHANGED...
No changes in the winter headlines as of now. We are monitoring
radar across the region and noticed that snow is beginning to
mix with rain along the Shenandoah Valley, along I-66 in
northwestern and northern Virginia, and into parts of central
Maryland. It appears, based on cameras, that light snow accumulations
are mainly confined to higher elevation so far. We are also monitoring
trends for the placement of the inverted trough and coastal low
pressure system.

&&

.KEY MESSAGES...
-1) Winter Storm Warnings and advisories remain in effect for
 portions of the area through early Monday. Locally significant
 snowfall accumulations and gusty winds will result in travel
 disruptions later this evening and into the Monday morning
 commute.

-2) Fast moving systems move through Tuesday night into
 Wednesday, and then again on Thursday, bringing additional
 chances for precipitation.

&&

.DISCUSSION...
KEY MESSAGE 1... Winter Storm Warnings and advisories remain in
effect for portions of the area through early Monday. Locally
significant snowfall accumulations and gusty winds will result
in travel disruptions later this evening and into the Monday
morning commute.

As of 10am, big snowflakes or light intermittent snow was mixing
with light rain and was noticed on radar and traffic cameras in
the Shenandoah Valley, along northern Virginia highways and just
northwest of Washington D.C. Elsewhere, light rain is occurring
and will soon be mixing with snow through the rest of this
morning and through much of this afternoon. Precipitation will
become a widespread mix of rain and snow across the region with
exception to all snow in the northwest zones this afternoon
before becoming predominantly light to moderate snow late this
afternoon and continuing into this evening. Snow accumulations
will be mainly higher elevations through mid-afternoon before
accumulating everywhere at all elevations late this afternoon.
Snow ratios will climb from single digits late this morning to
the middle teens by later this afternoon.

Temperatures remain in the middle to upper 30s with little
movement in either direction. They are expected to hold steady
for the most part with a slight and gradual trend toward the
freezing value the rest of the day.

The greatest impact from snow locally is expected later this
evening through predawn Monday morning as the coastal low tracks
off the Delmarva and the upper axis trough moves overhead.
Expect two areas of enhanced snowfall: one with the coastal low
that will encompass the western shore of the bay up into the
northeast/central MD and another with the inverted trough (or
norlun trough) across the Catoctin/Potomac Highlands. In
addition to this expect heavy upslope snow/squalls over the
Alleghenies given strong north/northwest flow.

The first area of enhanced snowfall rates will be close to
Chesapeake Bay, where mid- level frontogenetic forcing to northwest
of the coastal low will be strongest. Uncertainty remains in how far
west this area of heavier snow gets, but most solutions show it only
impacting the counties immediately adjacent to Chesapeake Bay in our
forecast area (St.Mary`s northward through Cecil). Snowfall rates
could approach an 1-2 inches per hour at times in this area between
roughly 7 PM and 3 AM. Near blizzard conditions are also possible
with gales over the waters and gusts in excess of 30-40 mph.

The second area of enhanced snowfall rates will be along an inverted
trough axis (sometimes referred to as a Norlun trough) that will
extend north to south through north-central portions of the forecast
area. Dynamically, this will occur along a low-level trough axis (in
the 900-700 hPa layer) where northeasterly winds in response to the
developing coastal low offshore converge with northwesterly winds
advancing beneath the upper trough. Model guidance remains in good
agreement that such a feature will occur, but there is still some
uncertainty with respect to the positioning. 00z CAMS have trended
slightly west with this features extending from Washington/Frederick
counties down through Jefferson/Loudoun/Fauquier counties. Such
features typically are very, very narrow in width (likely only 10-20
miles from west to east), and are notorious for producing very heavy
snowfall rates. Most guidance shows hourly QPF values of around 0.2-
0.4 inches, which would translate to 1-2 inches per hour of snow.
This feature will likely be either stationary or very slow moving
over several hours tomorrow evening into early tomorrow night. A
narrow band of 6-12 inches could occur as a result. Due to position
uncertainty, we spread this enhancement in precipitation out over a
slightly wider location than will likely occur in reality. Our
current forecast hedges the placement slightly more toward the
eastern solution (Washington County to Loudoun County), but has an
enhancement over that broader region. This is also why the Winter
Storm Warning extends southward in Fauquier Co. and wraps around the
DC Metro area.

The immediate DC Metro will likely fall within a relative min
between these two areas of precipitation enhancement, but will still
experience several hours of accumulating snow this evening into
tonight. Another localized minimum will be between the inverted
trough and the Allegheny Front where downslope flow could diminish
accumulations especially in eastern Mineral and eastern Grant
counties. Very little in the way of snow may end up falling in the
shadow of the mountains just to the east of the Allegheny Front and
also in the Central Shenandoah Valley.

Snow totals will be heavily elevation and snow rate dependent. With
such marginal temperatures in place, a lot of the snow will be lost
to melting at lower elevations with surface temperatures above
freezing, while higher elevations have lower temperatures and
accumulate more efficiently.

Snowfall: 2-4 inches is expected in the DC Metro, although there
could be locally lower totals at the lowest elevations if warmer
temperatures and lighter precipitation rates verify. 4-7 inches is
expected along the Bay shore from St. Mary`s northward through
Baltimore City, with higher totals of 6-12" from Carroll eastward
toward Cecil. Higher totals of 8-16 inches are expected in the
Catoctins, where snow will accumulate more efficiently throughout
the event. Snow will also accumulate efficiently southward along the
Blue Ridge, where a general 6-12 inches of snow is expected. To the
west of the Blue Ridge, snow totals will be heavily elevation
dependent, with 3-6 inches expected at higher elevations between the
Allegheny Front and Blue Ridge, while lower elevations in the
Central Shenandoah Valley and Potomac Highlands see little in the
way of accumulation. A general 1-3 inches is expected at lower
elevations along the I-70 corridor to the west of the Blue Ridge,
with the exception of near Hagerstown, where they could receive
significantly more snow under the inverted trough. For now, that
inverted trough area which extends southward from near Hagerstown
into Frederick and Loudoun is forecast to receive around 3-6", but
as mentioned before, the gradient will likely be tighter than
depicted, and the max there will likely be between 6 and 12 inches.
In the Alleghenies Winter Storm Warnings are in effect. Snow will
linger much longer there throughout Monday within upslope flow
behind the departing low. Snowfall accumulations there are expected
to reach 6-12 inches by Monday evening. Elsewhere, snow should wind
down by mid-morning Monday. For more details on the storm, including
exact placement of Winter Weather Advisories and Winter Storm
Warnings, see www.weather.gov/lwx/winter.

KEY MESSAGE 2..Fast moving systems move through Tuesday night into
Wednesday, and then again on Thursday, bringing additional chances
for precipitation.

A fast moving clipper low embedded within northwesterly flow aloft
will track to our north across the southern Great Lakes Tuesday
night, and then eastward across the Northeast on Wednesday. This
system looks to be rather moisture starved in nature, but should
produce some upslope snow in the mountains, with potentially a few
light snow showers spilling further east. A couple of inches of snow
accumulation may be possible in the Alleghenies during that time.

Another fast moving area of low pressure will descend down in
northwesterly flow across the Midwest and Ohio Valley Wednesday
night, before tracking eastward across the local area on Thursday.
This system appears as though it may be a bit stronger, and will
have more moisture to work with compared to the Tuesday
night/Wednesday system. Spread in model guidance is still high at
this time range, but many ensemble members show a soaking rain, and
a few show a bit of wintry precipitation as well.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
MVFR cigs and VFR vsbys expected for another couple of hours
into mid-afternoon hours, then falling even more to IFR and
LIFR as rain and snow mix transitions to all snow and becomes
heavy later this afternoon and into this evening. Precipitation
intensity will be light with a rain/snow mix for most of the day
outside of the mountain terminals. No accumulation is expected
at any of terminals through the 18z TAF period. Beyond 00z is
where snowfall accumulations look to become an issue especially
at MRB, IAD, BWI, MTN, and perhaps DCA as the coastal low surges
north and the inverted trough swings overhead. The heaviest
snow looks to occur between 02-07z where 1-2"/hr rates are
possible. Snow character will be wet for ground crews with
temperatures at or around freezing. Snow accumulations (slushy,
wet, and heavy consistency) right now look to sit between 2-6
inches across the corridor with higher totals north/east of
BWI/DCA/IAD. These totals are subject to change based upon any
shifts in the track of the coastal low and placement of the
upper level low nearby. Snow will taper off Monday, although it
is somewhat uncertain how quickly it moves out of the metro
terminals. Winds will also pick up out of the north to northwest
tonight, and remain gusty out of the northwest on Monday. Gusts
to around 30-35 knots appear likely within northwesterly flow
during the day Monday as VFR conditions return. Winds will
decrease Tuesday with VFR conditions continuing.

VFR conditions and south to southwesterly winds are expected on
Wednesday. Sub-VFR conditions appear possible at times on Thursday,
along with rain. Winds on Thursday will initially be out of the
south to southwest, before shifting around to out of the northwest
behind a cold front Thursday night.

&&

.MARINE...
Winds increase this afternoon, reaching SCA levels within
northerly flow. Gale Warnings have been issued south of the Bay
Bridge and across the lower tidal Potomac tonight within north
to northwesterly flow as low pressure strengthens offshore. Gale
Warnings remain in effect for all waters within northwesterly
flow on Monday as low pressure tracks off to our north and east.
SCA conditions likely linger within northwesterly flow through
Tuesday.

SCA conditions appear possible within south to southwesterly flow on
Wednesday and Thursday, as well as within northwesterly flow
Thursday night.

&&

.TIDES/COASTAL FLOODING...
As strong low pressure moves off the coast, northwesterly gales will
cause a sharp drop in water levels (blowout during low tide) Monday.
Some locations could approach low water thresholds, although the
latest forecast is not quite that low.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Winter Weather Advisory from 5 PM this afternoon to 10 AM EST
     Monday for DCZ001.
MD...Winter Storm Warning from 3 PM this afternoon to 10 AM EST
     Monday for MDZ003>006-008-011-014-017-018-503-505>508.
     Small Craft Advisory from 4 PM this afternoon to 2 AM EST
     Monday for MDZ008.
     Gale Warning from 2 AM to 6 PM EST Monday for MDZ008.
     Winter Weather Advisory from 5 PM this afternoon to 10 AM EST
     Monday for MDZ013-016-504.
     Winter Storm Warning until 6 PM EST Monday for MDZ501.
     Winter Weather Advisory until 7 AM EST Monday for MDZ502.
     Winter Storm Warning until midnight EST Monday night for
     MDZ509-510.
VA...Winter Storm Warning from 3 PM this afternoon to 10 AM EST
     Monday for VAZ031-501-505-506.
     Winter Weather Advisory from 5 PM this afternoon to 10 AM EST
     Monday for VAZ040-051-053>057-502-526-527.
     Winter Weather Advisory until 7 AM EST Monday for VAZ027>030.
     Winter Storm Warning until midnight EST Monday night for
     VAZ503.
     Winter Weather Advisory until 10 PM EST this evening for
     VAZ504.
     Winter Storm Warning until 7 AM EST Monday for VAZ507-508.
WV...Winter Storm Warning from 3 PM this afternoon to 10 AM EST
     Monday for WVZ051>053.
     Winter Storm Warning until 6 PM EST Monday for WVZ503.
     Winter Weather Advisory until 7 AM EST Monday for WVZ050-055.
     Winter Storm Warning until midnight EST Monday night for
     WVZ501-505.
     Winter Weather Advisory until 10 PM EST this evening for
     WVZ506.
MARINE...Winter Storm Warning from 3 PM this afternoon to 10 AM EST
     Monday for ANZ530.
     Small Craft Advisory from 4 PM this afternoon to 2 AM EST
     Monday for ANZ530-531-535-536-538-539.
     Gale Warning from 2 AM to 6 PM EST Monday for ANZ530-531-535-
     536-538-539.
     Small Craft Advisory until 5 PM EST this afternoon for
     ANZ532>534-537-540-541-543.
     Gale Warning from 5 PM this afternoon to 6 PM EST Monday for
     ANZ532>534-537-540>543.

&&

$$

DISCUSSION...ADS/KLW/KJP/EST
AVIATION...KLW/KJP/EST
MARINE...KLW/KJP/EST