Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

205
FXUS61 KLWX 271931
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
331 PM EDT Thu Aug 27 2026

.WHAT HAS CHANGED...
Severe T-Storm Watch is in effect for portions of the eastern
WV Panhandle, northern VA and portions of Maryland through 10pm.
Storm coverage looks to be scattered to broken with some
organization between 4-10pm.

&&

.KEY MESSAGES...
- 1) Warm and humid conditions combined with a front will lead
  to severe storms across parts of area through this evening.


- 2) Dry conditions this weekend with increasingly hot and humid
conditions through next week.

&&

.DISCUSSION...
KEY MESSAGE 1...Warm and humid conditions combined with a front will lead
to severe storms across parts of area through this evening.

Turning active this afternoon and evening as spokes of shortwave
energy/outflows ahead of an incoming cold front pass through the
region. A Severe Thunderstorm Watch will likely be issued for
portions of Maryland, northern-central VA, and the eastern WV
Panhandle. Storms look to initialize along the bay breeze
toward Baltimore/northeast MD and along a spoke of shortwave
energy pivoting between I-81 and the Blue Ridge between now-4pm
as the capping inversion buckles. Expect scattered to broken
lines or clusters of convection pushing northeast from the Blue
Ridge/I-81 impacting a large chunk of the metros between 5-9pm.
Not everyone will see the storms this afternoon and evening, but
something to monitor; especially if you have plans outdoors.

Hi-res guidance continues to struggle a bit in the evolution of
storms this afternoon given the capping inversion and a outflow
boundary zipping southwest from southern NJ/DE down along the
western shore of the Chesapeake Bay. The lead shortwave is up across
southern/central NJ with a secondary shortwave in the vicinity of
southwest and central VA, and the main cold front back toward the
Ohio River. It`s a matter of how these remaining pieces of energy
and lifting mechanisms interact, especially through the remaining
peak heating period for severe weather development.

Damaging winds will be the main threat with storms today given 30-35
kts of deep layer shear and modest instability values up of 1000
j/kg. Moderate mid level lapse rates (7-8 C/km), strong winds in the
upper atmosphere, and relatively light low level winds could also
result in some severe level hail. As mentioned in previous
forecasts, hi-res model guidance is still depicting some decent low-
level curvature to hodographs, especially along the MD/PA border in
northeast MD (due to perhaps a bay breeze/outflow from decaying
storms over southern NJ) which may increase low level shear.
The Storm Prediction Center continues a Slight Risk (Level 2 out
of 5) for severe weather through this evening.

Heavy rainfall will remain a concern given multiple rounds of
convection, especially over central and northeast MD where residual
outflow boundaries could slow up convection. Given relatively
unidirectional flow relative to the surface trough could result
in some training (hinted at by splotches of higher QPF in some
CAMs from Baltimore/Annapolis, MD points northeast; a secondary
area down around Fredericksburg/Stafford/Culpeper, VA). No Flood
Watches are planned at this time, but will need to be monitor
given PWATS over 1.5"+ and likely rain rates of 0.50-1" in a
30-45 minute period. While some showers and storms may linger
into the night, the severe weather threat should be winding down
after 9-10pm.

The slow moving cold front will bisect the area Friday morning while
the mid/upper level trough lags to the west. As a result, expect
additional showers and thunderstorms during the peak heating period,
especially along and south of the front. Highest probabilities for
severe weather appear to be south of I-66/US-50 across southern MD,
the VA Piedmont, and northern neck of VA. Damaging winds will be the
main threat along with locally heavy rainfall. Coverage once again
will be scattered, but highly dependent on where the front resides
and if any cloud cover lingers across the region.


KEY MESSAGE 2...Dry conditions this weekend with increasingly hot
and humid conditions through next week.

A cold front pushes through the area early Saturday morning, likely
stalling just south across southern VA to the Carolinas this
weekend. Surface high pressure builds south into the Mid-Atlantic as
winds shift quickly from north to easterly on Saturday. The high
moves offshore Sunday, bringing the return of southerly winds. While
we remain under broad troughing aloft, the presence of drier air at
the surface will keep rain chances out of the forecast. Lingering
humidity and building heat make for a warm and muggy weekend as
highs reach the 80s to around 90F.

Models are generally in good agreement that a strong mid-level ridge
builds across the southern U.S. and into the Mid-Atlantic during the
early to middle part of next week. This brings us well above normal
temperatures for late August as highs reach the low to mid 90s. Hot
and humid conditions are likely as heat indices reach to the low
100s east of the Blue Ridge.

A series of mid-level disturbances will ride along the top of the
ridge from the northern High Plains to the Northeast next week.
Depending on the exact position of the ridge, some of these
disturbances could be near or over our area come the middle to late
part of the week. For now, Monday and Tuesday look mostly dry,
though cannot rule out a stray thunderstorm or two given the
humid/unstable atmosphere. By Wednesday, the upper ridge begins to
retreat slightly, allowing the shortwave troughs to move over our
area. Several of the AI models indicate increasing severe potential
at some point Wednesday to Friday of next week, which is certainly
possible given the high instability that will be in place, along
with substantial upper-level support from any strong disturbance.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
VFR conditions will continue to prevail through this evening outside
of thunderstorms. Some patches of MVFR have been noted north and
east of BWI/MTN toward LNS/PHL given heavy thunderstorms.

A cold front will approach the region later this afternoon and
evening before pushing south of the area Friday evening. A few
strong to severe storms are possible during the afternoon/evening,
with gusty winds being the primary threat. Areas with the highest
confidence for storms include BWI, MTN, MRB ,and CHO) with slightly
lower confidence toward DCA points south and east. Went with TEMPOS
over these locations with PROB30s at DCA/MRB. Right now have storms
initiating along and west of a line from MRB/HGR to SHD between
now- 20z/-5pm and along the western shore of the bay during
this same time. Eventually activity will shift east likely in a
scattered to broken line between 21-01z/5-9pm. Storms could be
slow to push through, so there may be some prolonged period of
restrictions for those that do get storms through this evening.

Shower and thunderstorm activity may linger into the front half of
the overnight period prior to 5z/1am as the front stalls nearby.
Some MVFR and IFR cigs and vsbys may develop as a result. Current
guidance seems to be favor fog, especially west of the metro areas.
Showers and storms could even redevelop Friday, but unsure if this
would impact any of the terminals (CHO and perhaps DCA would have
the highest chances).

VFR conditions expected this weekend. Northerly winds shifting east
Saturday, then southerly Sunday, but remaining around 10 knots.

&&

.MARINE...
Small Craft Advisories remains in effect through 9pm this
evening for the middle and lower bay as well as lower tidal
Potomac due to southerly channeling.

A cold front will approach from the north and west later this
afternoon and evening bring the risk of strong gusty
thunderstorms. Special Marine Warnings will accompany this
threat, especially later this afternoon and evening. THe severe
threat will gradually diminish later this evening and into the
overnight hours.

Sub-small craft advisory level winds are expected on Friday as a
cold front moves in from the northwest. While some additional
thunderstorms are possible, the greater risk may be south of
Maryland.

Favorable marine conditions expected this weekend, with winds around
10 knots. North winds to start the day Saturday become east by the
afternoon, then south on Sunday.

&&

.TIDES/COASTAL FLOODING...
Increasing southerly flow continues through tonight, leading to
rising water levels. Most locations will only see action
stages, but Annapolis could approach minor flood stage early
Thursday morning. With the latest forecast only barely reaching
flood stage, will hold off on an advisory until confidence in
the water level trends increases.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 9 PM EDT this evening for
     ANZ531>534-537-539>541-543.

&&

$$

DISCUSSION...CJL/KRR/EST
AVIATION...KRR/EST
MARINE...KRR/EST