Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

551
FXUS61 KLWX 170125 AAA
AFDLWX

Area Forecast Discussion...UPDATED
National Weather Service Baltimore MD/Washington DC
825 PM EST Mon Feb 16 2026

.WHAT HAS CHANGED...
Possible fog formation overnight. Synoptically, setup appears
favorable tonight for fog to develop with upper ridge building
(i.e.subsidence inversion strengthening), moist ground from
yesterday`s rain, and light winds. However, model guidance show
dewpoints decreasing overnight, which indeed Metar trends show
is happening, and mid-high level clouds increasing. So, overall
confidence is not high for widespread dense fog overnight,
although patchy fog is certainly possible.

&&

.KEY MESSAGES...
- 1) Above average temperatures through Friday before
turning cooler and more unsettled late in the week.

&&

.DISCUSSION...
KEY MESSAGE 1...Above average temperatures through Friday before
turning cooler and more unsettled late in the week.

Behind an exiting shortwave trough that tracks further offshore
tonight, mid/upper heights will build in earnest through the week.
Over the next day, 500-mb heights are forecast to rise in response
to a longwave ridge currently over the middle of the country.
Characterized by 24-hour height rises of around 5-10 dm, this will
carry overall heights to around 560-567 dm. While heights lower a
bit through the latter portion of the work week, expect positive
height anomalies through much of the period. The ridge axis starts
to flatten by Thursday in response to a deep expansive trough
encompassing much of the western U.S. Eventually these lower
upstream heights make their way across the rest of the country by
Friday and into the weekend. The evolution of this trough and
corresponding pattern shift remains complicated at this juncture.
However, global ensemble temperature forecasts do show a downward
fall over the weekend and into early next week.

The surface pattern will feature a broad area of high pressure
tonight into Tuesday. Despite the anticyclone nearby, enough cloud
cover tonight should keep lows close to the freezing mark. The ridge
begins to drop toward the southeast which yields a south to
southwesterly return flow by Tuesday. 850-mb temperatures are
forecast to rebound to around 5-7C which supports the marked warm
up. Although forecast soundings show dry adiabatic mixing to around
900-mb, it does not appear profiles mix up to the 850-mb layer. As
such, this caps Tuesday`s high temperatures in the mid 50s to low
60s (warmest across central Virginia and from I-81 back to the
Allegheny mountain valleys). Looking ahead, Wednesday and Thursday
might be the warmest days of the period as highs soar into the low
to perhaps mid 60s. These could be a tad optimistic though based on
the added cloud cover and some increasing shower chances,
particularly by Thursday. With a west-east oriented frontal zone
arcing just north of the Mason-Dixon Line, any southward shift in
this boundary would also alter the temperature forecast. Mild
temperatures continue into Friday before a return to cooler weather
ensues over the weekend and into early next week.

An unsettled pattern is likely Friday and through the weekend. This
is in response to the initial trough and deep surface low which move
toward the Great Lakes on Friday. Eventually a cooler post-frontal
air mass ensues by Saturday morning. At the same time, the southern
stream begins to undergo some degree of amplification across the
southern U.S. How this system tracks on its eastward trek toward the
Atlantic coast will dictate any notable impacts to the local area.
Random deterministic models show a wintry precipitation scenario for
the second half of the weekend. However, there is still plenty of
uncertainty in this complex pattern that these random signals will
likely show up here and there. Will continue to monitor though.

Arctic high pressure builds across the middle of the nation by early
next week. This sets the stages for a cool start to the next work
week.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...

Low confidence on fog formation overnight due to decreasing
dewpoints and mid-high level clouds increasing. Best chance
still appears to be over BWI and MTN airports.

Guidance remains split on how far SW additional low clouds form
tonight. Currently highest odds across NE near BWI/MTN.

VFR Tue and Wed with mid to high clouds and low chance of
passing shower. Backdoor front brings wind shift Thu, except
perhaps CHO. Chance for rain showers increase Thu PM into Fri.

&&

.MARINE...

SCA conditions are possible Tue night into Thu morning, particularly
across the southern waters due to strengthening flow.

&&

.TIDES/COASTAL FLOODING...
Onshore winds return tonight into Tue which is expected to
result in higher tide levels across the area. Many sensitive
locations could reach Action Stage during high tide, with
Annapolis possibly reaching minor flood stage during the Tuesday
high tide cycles.

&&

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

&&

$$

DISCUSSION...LFR/BRO
AVIATION...LFR/CPB
MARINE...LFR/CPB