Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

167
FXUS61 KLWX 291100
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
700 AM EDT Tue Sep 29 2026

.WHAT HAS CHANGED...
Increased sky cover into the mostly cloudy category today. It`s
looking increasingly likely that there is rain in the area at
some point this weekend, but timing and coverage remains
uncertain.

&&

.KEY MESSAGES...
- 1) Tranquil weather is expected through Thursday with climbing
  temperatures.

- 2) Well above normal temperatures continue through Friday,
  but forecast confidence decreases moving into the weekend as
  rain chances increase.

&&

.DISCUSSION...
KEY MESSAGE 1...Tranquil weather is expected through Thursday
with climbing temperatures.

What`s left of the Nor`easter is over the Gulf of Maine today,
with cyclonic flow aloft still affecting the Mid Atlantic. A
broad moisture shield around the low continues to bring clouds
across the area, although several breaks and layers are noted on
satellite and in observations. Some patchy fog could develop in
any extended breaks (as seen at St. Inigoes MD).

This moisture remains pretty consistent throughout the day, so
mostly cloudy skies (with some breaks) will likely continue.
While temperatures may be held back a few degrees, high
temperatures should still reach the lower to mid 70s for most
locations. Some models are printing spotty light QPF this
afternoon as instability increases beneath the trough axis.
However, moisture will be shallow, likely limiting any
precipitation to sprinkles.

Skies should clear some tonight as ridging builds in at the
surface and aloft. This set up could be favorable for fog to
develop, although the coverage remains somewhat uncertain at
this time. Lows will be close to the dew points in the 50s.

The surface high will move off the coast late Wednesday into
Thursday while heights continue to increase. Temperatures will
climb further, with more locations reaching the 80s. Some spots
could even approach 90 by Thursday. Developing southerly flow
will lead to more sunshine. Dry weather is expected both days.
While nightly fog is possible, increasing southwesterly flow
just above the surface may limit low level saturation.


KEY MESSAGE 2...Well above normal normal temperatures continue
through Friday, but forecast confidence decreases moving into
the weekend as rain chances increase.

Another day of well above normal temperatures is expected on Friday.
850 hPa temperatures of around 16-18C should yield high temperatures
in the mid 80s to near 90 at lower elevations, and 70s in the
mountains. Clouds will be on the increase through the day, and a few
showers can`t be ruled out in western Maryland or the West Virginia
Panhandle during the afternoon as a cold front approaches from the
northwest. Guidance varies substantially from model to model and
ensemble member to ensemble member regarding the positioning of this
front through the upcoming weekend. With the frontal boundary in the
vicinity, there will be at least some chance for showers either day
this weekend, with ensemble guidance favoring higher chances on
Sunday. Forecast uncertainty remains high however, with ensemble
members showing high temperature solutions ranging from the upper
50s to low 90s Saturday, with cooler temperatures more likely by
Sunday. The frontal zone is likely to clear the area by Monday,
leaving below normal temperatures in its wake.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Moisture wrapping around what`s left of the Nor`easter will
continue to bring ceilings through today, although they will
most likely remain VFR. The overcast is widespread enough that
fog appears unlikely this morning, although a few patches could
develop if there are any breaks before sunrise. Light northwest
winds continue through the day.

Clouds should break tonight with light winds forecast. That
could result in fog, although coverage is uncertain. MRB and CHO
would have higher chances of lower visibilities, but will play
TAFs conservatively now until confidence increases.

VFR conditions will continue Wednesday and Thursday as high
pressure passes, with light winds turning southerly. Fog looks a
little less likely Wednesday and Thursday nights but can`t be
ruled out.

VFR conditions and southwesterly winds are expected on Friday.
Depending on the positioning of a front, sub-VFR conditions could be
possible on Saturday, but forecast confidence during that time
period remains low.

&&

.MARINE...
High pressure moving toward the area will provide light winds
through Wednesday. A northwesterly direction today will turn
southerly on Wednesday.

Southerly winds begin to pick up in strength on Thursday, with some
channeling effects possibly bringing gusts to near 20 knots
over the Chesapeake Thursday night.

Sub-SCA level winds are expected on Friday in south to southwesterly
flow. Winds are currently forecast to shift to out of the northeast
on Saturday, but forecast confidence remains low with a frontal
boundary nearby. SCA conditions are possible depending on the
frontal position.

&&

.TIDES/COASTAL FLOODING...
Some uncertainty exists for the remainder of the week as tide
levels remain elevated. Any subtle shifts upward could result in
minor flooding, particularly at Annapolis. However, Alexandria,
Dahlgren, and Havre de Grace may also be close at times. Minor
flooding could occur as soon as this evening`s high tide.
Evening tides would be favored going forward as well since they
are astronomically higher.

&&

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

&&

$$

DISCUSSION...ADS/KJP
AVIATION...ADS/KJP
MARINE...ADS/KJP