Area Forecast Discussion
Issued by NWS Sterling, VA

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927
FXUS61 KLWX 201902
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
202 PM EST Thu Nov 20 2025

.SYNOPSIS...
Cloudy and dry conditions look to continue through tonight with weak
wedging high pressure nearby. Rain chances return Friday into early
Saturday as an area of low pressure and series of fronts cross the
region. High pressure briefly builds back into the area Sunday and
Monday. Another wave of low pressure and front look to cross the
area Tuesday into the middle part of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
It`s another cloudy/gray afternoon across the region with cool
daytime temps and relatively mild lows. Highs will range from
the low to mid 40s along the PA/MD border to mid 50s across the
central VA Piedmont/Shenandaoh Valley. Lows will fall back into
the upper 30s and low to mid 40s with increased clouds and light
south/southeast winds at less than 10 mph. Dry conditions will
prevail for most locations with perhaps some patchy
drizzle/sprinkles across the western slopes of the Allegheny
Mountains at times this afternoon and evening.

High pressure will continue to push east across northern New England
today while remaining wedged east of the Appalachians. This will
lead to the continuation of a weak/hybrid CAD setup across the area
which will promote abundant cloud cover compared to sun. Some
filtered sun has been noted up across central/northeast MD this
morning and down across areas south of I-64 this afternoon
Unfortunately this will be short lived with cloud cover
thickening as low pressure approaches from the Ohio River
Valley.

Winds will remain light and variable this afternoon before switching
to the south and southeast this evening. This may help scrub out
some of the low level cloud cover east of the Alleghenies with
increasing mid and high level cloud cover expected through the
the evening/overnight hours.

Patchy fog is possible again late tonight given increased low level
moisture across the region. Confidence is low due to increased cloud
cover although areas north of I-66/US-50 could see a few breaks
leading to greater fog development. Dry conditions will prevail with
scattered rain showers moving into the western mountains and
Shenandoah Valley at or around daybreak Friday morning.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
Wedging high pressure will gradually buckle Friday morning as a warm
front lifts toward the Mid-Atlantic region. The warm front will lead
to some overrunning light rain shower activity, mainly west of the
Blue Ridge prior to daybreak Friday before spreading north and east
Friday afternoon. Rain shower activity looks to be light and
scattered across the area. Temperatures will also warm despite the
shower activity and added cloud cover with highs pushing into the
mid 50s and low 60s. Mountain locations will also warm into the low
50s making this an all rain event.

Low pressure will approach the area from the mid-Mississippi and
Ohio River Valleys late Friday afternoon and evening before crossing
overhead Friday night. The associated cold front with this system
will cross the area Saturday morning into Saturday midday. Some
uncertainty still remains in the overall timing and placement of
these features given the split flow jetstream pattern. The northern
stream remains much more amplified compared to the southern
jetstream which will likely inhibit the push of cold air advection
behind the front as the mean upper level trough advances east across
eastern Canada. Either way the area looks to see another round of
widespread beneficial rainfall Friday night into Saturday mid-
morning. Rainfall amounts of a tenth to a quarter of an inch can be
expected with locally heavier totals across the higher terrain. This
should help quell fire weather concerns for another few days
with additional rain chances by the middle part of next week
(see Long Term).

Low Temperatures Friday night will hold steady in the mid 40s to low
50s with highs Saturday back into the mid 50s and low 60s. Some
clearing may take place late Saturday afternoon and evening as the
cold front pushes east of the area. Cold air advection appears weak
with north to northwest flow (gusting 15-25 mph) in the wake of the
boundary. The colder air does not look to catch up until Saturday
night with lightening northerly winds and clearing skies across the
area. Lows Saturday night will fall into the upper 20s and low 30s.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
In the wake of Saturday`s cold front, slightly cooler temperatures
are expected Sunday, with highs only in the mid 50s (mid to upper
40s in the mountains).

A brief period of upper-level ridging will build over the region on
Monday. Expect slightly warmer temperatures as a result, with
continued dry conditions. This will continue for the first half of
the day on Tuesday. However, a strong upper trough begins to take
shape over the central CONUS during this time as well.

The details beyond this point become a bit murky, as there are
several pieces of upper-level energy to keep track of. Generally
speaking though, this trough moves toward the Northeast through the
middle portion of the week. There are hints at a powerful frontal
system developing and pushing through, but timing is very uncertain.
There also may be a system ahead of the main front around Tuesday.
However, guidance is still very split on how the upper-level pattern
actually evolves at this time.

High temperatures will be in the 50s and 60s each day with highest
elevations staying in the upper 40s. Overnight low temperatures drop
into the 30s and 40s each night.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
MVFR conditions look to continue amongst the terminals this
afternoon with a pocket of IFR conditions in and around the Potomac
Highlands/Catoctin Mtns (i.e KFDK/KMRB/KOKV). MVFR conditions look
to persists throughout the day at most of the terminals given light
onshore northeast to southeasterly flow. Some improvements to VFR
are possible later into the evening, especially across central and
northeast MD (i.e BWI and MTN) and down KCHO/KSHD where cigs have
already lifted. This is due largely in part to light northeast winds
switching to the southeast this afternoon which will weaken a
subsidence inversion aloft. As a result, expect less low level
clouds (outside of KMRB) and a scattered/broken mid-high level
cloud deck.

With increased low level moisture expect a continuation of a chaotic
cigs forecast as most of the terminals bounce between low end VFR
and MVFR throughout the day with pockets of IFR mainly west of a
line from MRB/CHO as low pressure approaches from the Ohio River
Valley. AMDs will be needed throughout the day to encompass these
near term trends. Cloudy skies continue tonight with rain shower
activity moving into locations west of KMRB/KCHO near daybreak
Friday. Some fog is also possible in areas that see breaks within
the clouds. Highest confidence for this would be north of KIAD and
KDCA although uncertainty remains with added cloud cover.

Winds shift to the south Friday as a warm front slowly lifts
through. Some sub-VFR conditions are possible in lower CIGs and -RA
at times. Low pressure and its cold front will follow Friday night
into Saturday with increasing potential for lower CIGs and VSBYs due
to more widespread rain through early Saturday morning. VFR is
expected to return by late Saturday afternoon as the cold front
moves away and drier air moves in.

VFR conditions are expected on Sunday and Monday with light
southwest winds on Sunday before turning light and variable on
Monday under high pressure.

&&

.MARINE...
Sub-SCA Level winds are expected through Friday morning. Winds will
remain light and variable this afternoon while switching to the
southeast at less than 10 kts. Southerly winds are expected Friday
as a warm front slowly lifts across the waters. The front will bring
a few light scattered showers to the waterways late Friday morning
into Friday afternoon. More widespread rain shower activity holds
off until Friday evening and night as an area of low pressure and
cold front cross the region.

Winds may increase out of the south (leading to channeling) for a
short time window ahead of the low pressure system late Friday, then
increase a bit more readily in the wake of the cold front Saturday.
SCAs are possible late Friday through Saturday before winds become
lighter under building high pressure Saturday night.

Southwest winds around 10 knots are expected on Sunday before
turning more variable in direction on Monday under high pressure.

&&

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

&&

$$

SYNOPSIS...EST
NEAR TERM...EST
SHORT TERM...EST
LONG TERM...CJL
AVIATION...CJL/EST
MARINE...DHOF/CJL/EST