Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

093
FXUS61 KLWX 290621
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
221 AM EDT Thu Oct 29 2026

.WHAT HAS CHANGED...
Expansive low clouds are developing east of the Blue Ridge, with
river valley fog to the west. Rain chances for Sunday into Monday
continue to decrease.

&&

.KEY MESSAGES...
- 1) Above normal temperatures through Friday, then seasonable
  with increasing clouds this weekend.

- 2) Rain chances remain uncertain for the first half of next
  week.

&&

.DISCUSSION...
KEY MESSAGE 1...Above normal temperatures through Friday, then
seasonable with increasing clouds this weekend.

A couple of consecutive days of light onshore flow has increased
low-level moisture enough to result in (1) river valley fog west
of the Blue Ridge (locally dense at times), and (2) low clouds
banking along and east of the Blue Ridge and Catoctin Mountains.
Clouds/fog are more expansive relative to Wednesday morning, but
should burn off and lift by midday to early afternoon as winds
shift from southeast to southwest.

The NAM seems to be handling the low-level moisture profiles
best, with low clouds favored east and areas of fog west (as
opposed to a lot of other guidance which maintains a dense fog
threat to the east with minimal fog to the west).

After the clouds break, mixing on these light southwest winds
should allow temperatures to reach into the lower to middle 70s
(60s mountains). Low temperatures tonight will be seasonable
in the 40s to lower 50s, but may be rather variable over short
distances depending on where goes calm and where holds onto a
light southwest wind. Higher elevations will actually hold on to
more southwest breezes and be poking up into the warming airmass,
and could therefore be some of the warmest spots tonight.

Well above normal temperatures persist Friday, despite a cold
front crossing the region. Cold air advection lags behind this
front, and downsloping flow likely allows for highs to push
well into the 70s (60s mountains). One caveat is if some
stratocumulus develops on northwest flow, but the background
airmass is rather dry so the chance of that happening and it
having a significant impact on temperatures is limited.

Eventually, some cooler temperatures will filter into the region
Friday night through the weekend. Expect seasonable and dry
conditions as high pressure holds firm, with any precipitation
becoming less likely through at least Sunday evening.


KEY MESSAGE 2...Rain chances remain uncertain for the first
half of next week.

Strong high pressure will remain overhead Sunday and only gradually
drift eastward through the first half of next week. The Mid-Atlantic
will be caught in between more prominent but slow moving troughs
(or closed lows) near Florida/the Bahamas, the Plains, and eastern
Canada. Some models still show potential for a shortwave trough
to ride around the departing ridge, but at this point the chance
for rain has dropped to 30 percent or less between Sunday night
and Tuesday night. Even though conditions may largely remain dry,
expect more cloud cover between onshore surface flow and a warm
advection pattern aloft. Temperatures will likely remain a little
above normal through this period despite the extra clouds. The
Plains trough may eventually increase rain chances Wednesday or
Thursday as it moves eastward, but its progression is uncertain
as well.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
Low clouds (FL025-FL035) will continue to bank up the east side
of the Blue Ridge and Catoctin Mountains, expanding across the
I-95 corridor through daybreak. Ceilings may gradually lower,
possibly breaching IFR 11Z-13Z, though given recent trends MVFR
may be more favored. Some guidance continues to produce LIFR in
fog, though that potential seems lower given the MVFR cloud
deck. MTN could have intermittent IFR VSBY as they will be the
last to get under the cloud deck, and CHO has a bit higher
chance of IFR as well given added moisture pooling in proximity
to the Blue Ridge. To the west, low clouds may attempt to sneak
up the Potomac River Valley, but south to southwest flow likely
keeps clouds to the east of MRB. Here, fog is developing, and
may become dense at times for several hours from 09Z-13Z. Light
SE flow early this morning becomes SW today through tonight with
VFR expected to return 15Z-18Z. Low cloud/fog potential appears
lower tonight given a persistent albeit light SW wind.

VFR is likely Friday as winds shift to the northwest. Gusts of
20-25 knots are likely around midday into mid afternoon as a dry
cold front crosses. Winds become lighter Friday night into
Saturday while shifting to the north, with light east to calm
winds Saturday night as high pressure builds.

Significant weather is unlikely Sunday and Monday as high pressure
moves eastward. However, some low chances of sub-VFR ceilings and a
few rain showers exist Monday depending on how the weather pattern
evolves.

&&

.MARINE...
Light south to southwest winds are expected through tonight,
though a few gusts around 15 knots are possible at times. A dry
cold front will shift winds to the northwest Friday, with near
shore and narrower waterways having the potential to see gusts
to near 20 knots at times. Northerly channeling Friday night may
prompt Small Craft Advisories before diminishing Saturday. Winds
then shift to the east Saturday night as high pressure builds.

Light winds will likely continue Sunday and Monday as high pressure
gradually moves offshore.

&&

.TIDES/COASTAL FLOODING...
Tidal anomalies remain elevated, though have been slowly
decreasing so far tonight. Some fluctuation is possible over the
next 12-24 hours which could send vulnerable shoreline to near
minor flood stage this evening.

Offshore flow decreases tide levels Friday into Saturday. Winds
turn back around out of the south at low speeds which could
cause a modest rebound in tides by Sunday.

&&

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

&&

$$

DISCUSSION...ADS/DHOF/CPB/SRT
AVIATION...ADS/DHOF/CPB/SRT
MARINE...ADS/DHOF/CPB/SRT
TIDES/COASTAL FLOODING..DHOF