Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

283
FXUS61 KLWX 240803
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
403 AM EDT Thu Sep 24 2026

.WHAT HAS CHANGED...
A Coastal Flood Warning was issued for Alexandria. This replaces
a Coastal Flood Advisory and Coastal Flood Watch that were
previously in place.

&&

.KEY MESSAGES...
- 1) Dry, breezy conditions and below normal temperatures are
  expected for today and Friday.

- 2) Remaining breezy while turning warmer this weekend despite
uncertainty in regards to impacts from coastal Nor`easter nearby.

&&

.DISCUSSION...
KEY MESSAGE 1... Dry, breezy conditions and below normal
temperatures are expected for today and Friday.

The upper trough axis that has lingered to our west for several
days now will finally progress off to our east today. Dry
conditions are expected locally, but winds will remain gusty
out of the north as high pressure remains in place to our north
and a coastal low starts to develop offshore. There will be
enough remnant low-level moisture around for a stratocumulus
deck to form in response to daytime heating. Temperatures will
run well below normal, with highs in the 60s at lower
elevations, and 50s in the mountains.

Skies are expected to clear out tonight as drier air works in
from the north. The pressure gradient may weaken just enough
tonight for some of the more sheltered valleys in the
Alleghenies to decouple. If this occurs, some of the highest
mountain valleys may get a little frost, with temperatures
dropping back into the 30s. Current thinking is that coverage of
the frost will be low enough to preclude the issuance of a
Frost Advisory for those locations, but we`ll continue to
monitor the situation. Further east, we`ll likely maintain
enough of a pressure gradient for winds to persist. Overnight
lows are generally forecast to be in the 40s to the west of
I-95, and lower 50s to the east of I-95.

Sunnier skies are forecast tomorrow, along with slightly warmer
temperatures. Winds will remain gusty out of the north (gusts to
around 20-25 mph possible), and temperatures are forecast to
reach into the lower 70s at lower elevations, with 60s in the
mountains.

KEY MESSAGE 2...Breezy and warmer this weekend, but forecast
remains uncertain as Nor`easter impacts Northeast U.S.


Anomalously strong surface ridge (by late September standards)
finally weakens this weekend as a strong Nor`easter develops off the
East Coast. Ensemble members still show quite a bit of spread
regarding the exact track of the Nor`easter. A few members show
the possibility the low tracks closer to the NJ / Delmarva coast
this weekend. Regardless of exact position, we are likely to be
on the drier (subsidence) side of the system with northwest
winds bringing in breezy, warmer, and mostly dry conditions. If
the Nor`easter tracks closer to our area that could bring some
rain chances to the area, especially along/east of I-95, along
with the potential for increasing winds. Safe to say that there
isn`t a definite trend for this weekend, so be sure to keep
track of the forecast for any changes in the coming days.

The Nor`easter is eventually pushed offshore at the start of next
week as high pressure builds in from the OH Valley and Great Lakes.
Mid-level ridging builds over much of the eastern CONUS during the
middle of next week, marking the return of much warmer temperatures
and continued dry conditions.

&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
VFR conditions are expected at the terminals through the
upcoming weekend into early next week. There will be a broken
deck of stratocumulus clouds around FL030 to FL040 through much
of the day, and a few MVFR clouds can`t be entirely ruled out
shortly after sunrise. Those clouds likely dissipate by this
evening.

Winds are forecast to be gusty out of the north to northeast
today, north tomorrow, and north to northwest this weekend.
Gusts to around 20-25 knots appear likely today. The magnitude
of the gusts Friday through Sunday will be dependent on the
track of a coastal storm. Lighter northwesterly winds are
forecast for Monday.

&&

.MARINE...
Gale Warnings for the waters surrounding Southern Maryland drop
back to Small Craft Advisories at 6 AM. SCAs are then in effect
for all waters in north to northeasterly flow through 6 AM
Friday. Forecast uncertainty increases substantially later
Friday through the weekend as a coastal low strengthens and
then potentially retrogrades westward toward the Mid- Atlantic
coast. SCA conditions appear to be the most likely scenario
during the daylight hours Friday, but a few Gale gusts could be
possible. The forecast gets considerably more interesting
Friday night into Saturday. At least SCA gusts appear likely to
persist through this time period in northerly to north-
northwesterly flow. However, if the coastal low were to track
very close to the coast (as advertised by the 00z Euro), Gale
conditions would be likely, and even a few Storm force gusts
couldn`t be ruled out. Due to the unusually high level of
forecast uncertainty during that time period, no additional
headlines were issued overnight. But if solutions continue to
trend toward the closer to the coast solution, Gale Watches may
potentially need to be issued today. SCA level gusts likely
persist in northwesterly flow on Sunday as the system pulls
away, before winds finally drop back to sub-SCA levels on
Monday.

&&

.TIDES/COASTAL FLOODING...
A long duration coastal flood event within persistent onshore
flow is underway. Coastal Flood Warnings are in effect for
Annapolis, Straits Point, and Alexandria through Friday. Coastal
Flood Advisories are in effect for DC, Dahlgren, and Solomons
Island through Thursday night. Further north along the Bay
(Baltimore northward) anomalies are forecast to be lower due to
a significant northerly component of the wind.

The forecast gets very complicated later Friday into Saturday as
a coastal low strengthens and potentially retrogrades westward
toward the area. Model guidance shows an extreme amount of
forecast spread with respect to tidal levels Friday afternoon
through the weekend. This uncertainty is tied to uncertainty in
the placement of the aforementioned coastal low, and whether its
associated wind field will allow water to be able to start to
drain out of the mouth of the Bay. Further coastal flood
headlines may be needed during this time period, but it`s also
possible that water levels begin to decrease significantly
starting Friday night.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Coastal Flood Advisory until 9 AM EDT Friday for DCZ001.
MD...Small Craft Advisory until 6 AM EDT Friday for MDZ008.
     Coastal Flood Warning until 11 AM EDT Friday for MDZ014.
     Coastal Flood Advisory until 7 AM EDT Friday for MDZ016.
     Coastal Flood Warning until 5 PM EDT Friday for MDZ017.
     Coastal Flood Advisory until 8 AM EDT Friday for MDZ018.
VA...Coastal Flood Advisory until 7 AM EDT Friday for VAZ057.
     Coastal Flood Warning until 10 AM EDT Friday for VAZ054.
WV...None.
MARINE...Small Craft Advisory until 6 AM EDT Friday for ANZ530>532-535-
     536-538>540.
     Gale Warning until 6 AM EDT early this morning for ANZ533-534-
     537-541>543.
     Small Craft Advisory until 6 AM EDT Friday for ANZ533-534-537-
     541>543.

&&

$$

DISCUSSION...KJP/KRR/EST
AVIATION...KJP/KRR/EST
MARINE...KJP/KRR/EST