Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

622
FXUS61 KLWX 182030
AFDLWX

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

.WHAT HAS CHANGED...
The Winter Weather Advisory for this afternoon has been trimmed
to Cecil County. A Small Craft Advisory has been issued Monday
and Monday night. A Cold Weather Advisory has been issued Monday
night into Tuesday morning for locations along and west of the
Allegheny Front.

&&

.KEY MESSAGES...
- 1) Low pressure passing offshore will result in a second round
  of rain and snow, mostly along and east of Interstate 95
  through early evening.

- 2) Very cold conditions are expected over the region Monday
  night through Tuesday night.

- 3) Seasonal conditions Thursday turn cold into next weekend
  with the possibility of wintry precipitation.

&&

.DISCUSSION...
KEY MESSAGE 1...Low pressure passing offshore will result in a
second round of rain and snow, mostly along and east of
Interstate 95 through early evening.

Low pressure is located east of the Outer Banks this afternoon,
moving northeastward. A mid/upper level trough and associated
jet streak are interacting with the trailing baroclinic zone to
spread precipitation well west of the low track. Light
precipitation is entering central Virginia and southern
Maryland areas, with the edge of the precipitation shield
trailing into the central Carolinas. Temperatures east of the
Blue Ridge are largely in the mid to upper 30s. Across southern
Maryland, even the dew points are still above freezing, although
dry low level air continues to advect on northwest winds. Thus
some areas may initially see rain, although snow will become
increasingly common as the precipitation advects northward into
and is undercut by the colder/drier air. Given the marginal
thermal environment and relatively short duration of potential
snow (perhaps 3-4 hours at most), forecasts for additional
accumulations have trended downward. Most locations will see an
inch or less. If a changeover occurs quickly enough, southern
Maryland could end up with the highest amounts. Secondarily,
Cecil County will also be near the western edge of the steadier
precipitation, and with colder air in place there (especially
the northern part of the county), have left the existing Winter
Weather Advisory in place until 6 PM. While there is still a bit
of uncertainty, the back edge of steadiest precipitation is
still expected to closely align with Interstate 95, although a
westward bulge has resulted in brief snow around the
Charlottesville area which will lift northeastward through the
piedmont.

The low will pull away and precipitation will end early this
evening. Given cold temperatures and not a lot of wind, any
residual moisture will likely refreeze on untreated surfaces
overnight given low temperatures from the mid teens to mid 20s.

Secondarily, some light snow showers or flurries are affecting
the Allegheny Mountains this afternoon due to shallow moisture
and lift in the DGZ. However, minimal accumulations are
expected.

KEY MESSAGE 2...Very cold conditions are expected over the
region Monday night through Tuesday night.

An Arctic front will sweep through the area Monday, ushering in
gusty winds and a very cold airmass. Westerly winds will gust 20
to 35 mph during the day, with locally to around 45 mph in the
higher elevations. It will be close to Wind Advisory criteria
there, but think areas with higher gusts will be isolated. While
highs will reach the 30s and lower 40s in the lower elevations
during the day, temperatures will rapidly fall after sunset.
Winds will decrease somewhat overnight, but air temperatures
will drop to the teens, with single digits in the higher
elevations. Monday night will have the lowest wind chill values,
generally 0 to 10 in the lower elevations and below 0 in the
higher elevations. A Cold Weather Advisory has been issued along
and west of the Allegheny Front where there will be widespread
wind chills between -10 and -20. This advisory will continue
through 1 PM Tuesday, as temperatures will be slow to climb and
winds will remain gusty. Temperatures have trended upward
slightly for Tuesday, with locations across central Virginia and
southern Maryland potentially rising above freezing briefly.
Most other locations will stay in the mid to upper 20s. Winds
will also be slightly less than Monday but still keep wind
chills from getting any higher than the teens and lower 20s.

A shortwave trough will also cross the northwestern part of the
CWA as the Arctic front passes. Some scattered upslope snow
showers will be possible Monday along the Allegheny Mountains.
Very little moisture is expected, but high snow ratios in the
cold airmass could result in a fluffy inch of snow in spots.

The center of the strong high will build over Tuesday night with
mostly clear skies in place. Due to the radiational cooling
component with lighter winds in place, some of the outlying
valleys could have colder air temperatures compared to Monday
night (single digits). Otherwise lows in the teens are expected
across the lower elevations. Some residual wind in the higher
elevations could result in wind chills below 0.

As the high slides east Wednesday, gusty south winds will push
most of the area into the mid 30s to lower 40s. During the
afternoon and overnight, some snow showers may enter the
Alleghenies as the next low pressure system moves into the Great
Lakes.

KEY MESSAGE 3...Seasonal conditions Thursday turn cold into next
weekend with the possibility of wintry precipitation.

Surface high pressure slides offshore Thursday as an area of low
pressure passes by to our north. The return of southerly flow brings
highs up to their seasonal values in the low to mid 40s east of the
mountains. An approaching upper trough and an associated surface
cold front bring a period of upslope mountain snow showers, with
several inches of accumulating snow possible. The cold front crosses
the area Thursday evening/night.

An Arctic airmass settles in over the region Friday into next
weekend, with well below normal temperatures possible. We could be
looking at highs in the 20s and 30s for next weekend, and overnight
lows in the teens to low 20s. Truly frigid air could arrive next
Sunday night into the start of the following week.

Models continue to indicate the interaction of the northern and
southern jet streams over the central U.S. producing a potent area
of low pressure. There is a lot of uncertainty regarding the timing,
location, and track of this system. Depending on what occurs, there
could be wintry precipitation of varying types across our area
sometime next weekend. To add some probabilistic perspective, the
13Z NBM has around a 30pct chance for 1-2 inches of snow, and around
a 20pct chance for a glaze of ice. Continue to monitor the forecast
during the upcoming week.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
As a wave of low pressure moves off the coast, the secondary
area of precipitation is spreading northward from the Carolinas,
although it is battling dry air on the northwest side. With that
said, precipitation is reaching the ground on the western side
of the model guidance envelope, even if it won`t accumulate
much (should be less than 1 inch). Snow has reached CHO, and
will likely graze IAD for an hour or so as well. At this rate,
snow is more certain for DCA/BWI/MTN, with the longer duration
at the latter two. However, it should only be a 3-4 hour
duration at most, and could start as rain for a time. While IFR
conditions are possible, the snow will most likely remain light
in intensity. Snow should end by 23Z with VFR conditions
returning, but temperatures will quickly fall and winds will
remain rather light out of the northwest, so any residual
moisture could refreeze on untreated surfaces.

Winds will become south or southwest by Monday morning, then an
Arctic front will sweep through during the midday hours,
shifting winds to the west. No precipitation is expected, but
these winds will gust 20-30 kt during the afternoon and early
evening before subsiding somewhat overnight. Wind gusts of 20-25
kt will return Tuesday, becoming light Tuesday night as high
pressure builds overhead. In its wake, southerly winds may gust
to 20 kt on Wednesday.

VFR conditions likely continue into Thursday when a cold front moves
through the area. Winds veering from southwest to northwest from
morning to evening, and could see gusts to around 20 knots.

&&

.MARINE...
North to northwest winds will remain elevated into the night as
low pressure passes offshore. A Small Craft Advisory is in
effect for most of the waters until 4 AM. A period of rain/snow
is also expected this afternoon into early evening. Winds shift
briefly to southerly Monday morning ahead of a reinforcing
Arctic front which will turn winds west to northwest Monday
afternoon through Tuesday. Gusts of 20 to 30 knots are most
likely from roughly midday Monday through Monday evening,
gradually decreasing late Monday night. A Small Craft Advisory
has been issued for this period as well, and a few gusts could
approach gale force Monday evening. Advisories will likely be
needed for most if not all waters Tuesday as westerly winds
remain gusty, but not as strong as Monday. Light winds are
expected Tuesday night as high pressure builds overhead.
Southerly winds will quickly increase in its wake Wednesday,
with SCAs likely needed into Wednesday night.

SCA conditions are possible Thursday as a cold front moves across
the local waters.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 4 AM EST Monday for MDZ008.
     Small Craft Advisory from 9 AM Monday to 6 AM EST Tuesday for
     MDZ008.
     Winter Weather Advisory until 6 PM EST this evening for MDZ008.
     Cold Weather Advisory from 8 PM Monday to 1 PM EST Tuesday for
     MDZ501-509-510.
VA...Cold Weather Advisory from 8 PM Monday to 1 PM EST Tuesday for
     VAZ503.
WV...Cold Weather Advisory from 8 PM Monday to 1 PM EST Tuesday for
     WVZ501-503-505.
MARINE...Small Craft Advisory until 4 AM EST Monday for ANZ530>534-537-
     539>541-543.
     Small Craft Advisory from 9 AM Monday to 6 AM EST Tuesday for
     ANZ530>534-537>543.
     Winter Weather Advisory until 6 PM EST this evening for ANZ530.
     Small Craft Advisory from 9 AM Monday to 1 AM EST Tuesday for
     ANZ535-536.

&&

$$

DISCUSSION...ADS/KRR
AVIATION...ADS/DHOF/KRR
MARINE...ADS/KRR