Area Forecast Discussion
Issued by NWS Sterling, VA

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326
FXUS61 KLWX 300029
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
829 PM EDT Fri Aug 29 2025

.SYNOPSIS...
High pressure will slowly drift north and east of the area this
weekend into early next week. Cooler than normal temperatures and
mainly dry conditions look to continue as a result, outside of a
passing shower or thunderstorm over the Alleghenies. More
substantial rain chances do not look to return until the latter half
of next week as a series of fronts cross the region.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Synoptically, not too much has changed in the overall forecast.
Longwave troughing will remain over the eastern CONUS as surface
high pressure builds south and east from the Great Lakes region. The
cold front from earlier this afternoon will continue to exit the
area this evening with a subtle jet streak set to pass aloft heading
into the front half the overnight period. The jet streak combined
with the exiting front and lagging high pressure system will promote
some residual high clouds over the region heading into the pre-dawn
hours of Saturday morning. This may result in a slower drop in
temperatures across the region. Even with that said, expect a cooler
start Saturday morning with lows in the upper 40s and low to mid
50s. City centers will see lows in the upper 50s while high valley
and mountains locations see lows in the mid 30s to low 40s. Typical
colder pockets such as the The Glades of Garrett Co. MD, Mill Gap,
VA, and the Cabin Mountain/Canaan Valley, WV cold drainage could see
lows below freezing if low clouds don`t develop. Confidence in this
is low given some subtle onshore flow as winds change to more of a
northeasterly direction. Some patchy fog is possible in the river
valleys west of I-81 tonight pending on how quickly cloud cover
clears out.

High clouds will quickly dissolve Saturday leading to mostly sunny
conditions across the region. Meanwhile, surface high pressure will
begin to wedge south as it works into the eastern Great Lakes and
interior Northeast. Dry conditions will prevail with cooler than
normal temperatures continuing. Highs Saturday will push into the
mid to upper 70s for most locations with mid 60s to low 70s across
the mountains. Overnight lows Saturday night will fall back into the
upper 40s and low to mid 50s.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
Broad upper level troughing will continue to maintain cooler than
normal temperatures and mostly dry conditions through the short term
period. A more prominent shortwave trough will pivot across the area
Sunday which may increase cloud cover. Moisture will pool along an
inverted trough draped over the central Appalachians, so a few
showers and thunderstorms are possible in the southwestern corner of
the CWA (i.e Virginia Allegheny Highlands region over to the central
Blue Ridge), especially during the afternoon hours. Most locations
will remain dry with wedging high pressure nearby. Highs Sunday will
push back into the mid to upper 70s and low 80s with mid 60s and low
70s over the mountains. Lows Sunday night will fall back into the
low to mid 50s with both the Baltimore/Washington DC city centers
hovering around 60 degrees.

High pressure further wedges itself down the eastern face of the
Appalachians Monday. This will lead to a return of dry conditions
across the entirety of the region as shortwave energy kicks east and
the inverted trough waivers south and west. Highs Monday will push
into the mid to upper 70s and low 80s. Mountain locations will be a
a touch cooler in the upper 60s and low to mid 70s. Lows Monday
night will fall back into the 50s. Skies will trend partly
cloudy under light easterly flow.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Wedging high pressure will shift toward the southern New England
coast Tuesday into Wednesday. Meanwhile, a cold front will work east
from the Midwest and Ohio River Valley with a secondary low pressure
system set to work out of the lower Mississippi River Valley toward
the Carolina coast. The coastal low pressure system looks to remain
offshore as the cold front pushes into the area Thursday and Friday.
This is our next opportunity for rain across the area. Chances appear
to be scattered to widespread Thursday and Friday with a focus
especially west of the Blue Ridge and east of I-95. Rain will be
much needed at this point given one of the driest August`s on record
across the region.

As for severe weather, the threat remains low with a focus on
Thursday into Friday as the front pushes in. SPC gives us a
honorable mention on Day 7 with CSU learning probs highlighting 5-15
percent probs and the CIPS/NSSL probs highlighting 10 percent probs
across the region. If severe weather, were to occur it would be in
the form of wind and hail given the drastically cooler airmass
behind the front fro the upcoming weekend ahead. High pressure
returns for the start of the weekend with a secondary cold front to
follow beyond the long term period.

Temperatures will remain cooler than normal throughout much of next
week. Expect highs in the mid 70s and low 80s with lows in the 50s.
Mountain locations will be a touch cooler in the mid 60s and low 70s
with lows in the 40s and 50s.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions are expected through the valid TAF period as a cold
front departs the area and high pressure builds in from the Great
Lakes region. SCT-BKN cumulus will break up this evening with some
residual high level clouds as a jet streak aloft passes
through. Wind gusts will also drop with a shift to the north and
northwest overnight and eventually northeast heading into
Saturday at less than 10 kts. VFR conditions will continue into
the holiday weekend and early next week as wedging high pressure
wedges north of the area. This will lead to dry conditions
across the area outside of some spotty showers and thunderstorms
mainly west of KSHD and south of KCBE where an inverted trough
will linger nearby. Highest chances for precipitation at these
terminals will be on Sunday afternoon and evening. There is also
the potential for low clouds and fog near and west of KMRB/KCHO
Sunday through Tuesday night given the light onshore
east/northeast flow.

VFR conditions look to continue through Wednesday as high pressure
shifts toward the southern New England coast. Shower and
thunderstorm chances return late next week as a series of fronts and
low pressure systems cross the region.

&&

.MARINE...
Northerly channeling may result in near SCA level gusts tonight, but
it may be marginal/brief in nature. Otherwise, high pressure will
start building north of the area over the weekend. Weaker pressure
gradients should keeps winds less than advisory criteria as they
shift to northerly Saturday and northeasterly or easterly Sunday.

High pressure lingers over southern New England into NY for the
start of next week. This will mostly keep winds below SCA levels in
the Chesapeake Bay and other local waters. The pressure gradient on
the southern periphery of the ridge could strengthen Monday night
into Tuesday morning, and this could bring winds closer to SCA
levels.

&&

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

&&

$$

SYNOPSIS...EST
NEAR TERM...CPB/EST
SHORT TERM...EST
LONG TERM...EST
AVIATION...CPB/EST
MARINE...CPB/EST