510
FXUS61 KLWX 260903
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
403 AM EST Fri Dec 26 2025
.SYNOPSIS...
High pressure will hold firm over Quebec while low pressure dives
from Ohio to off the Virginia coast through tonight. High pressure
will briefly gain control Saturday before a strong frontal system
moves through late Sunday into Monday. Another weaker front may
approach by the middle of next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
1031 mb high pressure over James Bay is pushing southward, with
a cold air damming pressure pattern already evident in the
isobars east of the Appalachians. While high level clouds are
increasing, the shortwave trough responsible for driving the low
pressure system later today is still in the upper Midwest. There
are some spotty light warm advection shower across the Ohio
Valley. While some of these will approach the western CWA toward
sunrise, they likely won`t produce much precipitation and
eventually evaporate as they encounter the dry low level air
east of the mountains.
East of the Allegheny Front, not much measurable precipitation
may arrive until this afternoon. The passage of the deepest
moisture is actually somewhat brief and coincident with the mid
level trough passage between mid afternoon and mid evening.
Combined with better forcing being displaced to the north, it
may be difficult to precipitate long enough, hard enough, to
saturate the very dry low level airmass. High precipitation
amounts continue to be along the I-68/I-70 corridor and along
the Allegheny Front, with a secondary increase east of I-95 as
the surface low develops off the coast. Without heavy
precipitation, it may be easier for more locations to rise above
and stay above freezing for the duration of the event. The quick
erosion of the surface high also allows winds to become
southerly rather quickly. It`s possible southern portions of the
existing advisory don`t get much freezing rain...the main threat
is on the ridges. The Ice Storm Warning may also be marginal at
best (around one quarter inch) due to the lower precipitation
amounts and potential for warm air to take over by evening. The
only area that may need to be monitored is western Pendleton and
all of Highland Counties, where some light freezing rain could
fall depending on the timing of precipitation vs. temperatures.
The window for sleet may narrower as well as much warmer air
aloft moves in not long after precipitation begins.
Precipitation will wind down in the late evening to early
overnight hours, lasting longest over northeastern Maryland, as
the low pulls off the coast. While low level moisture/clouds
will linger, the ensuing northerly wind is not the most
favorable for drizzle except perhaps along the Allegheny Front.
Most areas will remain above freezing overnight, though some
places near the Pennsylvania border may hover right around 32.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
High pressure builds back in from the north Saturday and
Saturday night. A lingering baroclinic zone and wind direction
turning more northeasterly may allow for some patchy drizzle to
develop, especially along the I-95 corridor. Low clouds likely
remain in place much of the day as well, keeping highs in the
upper 30s to mid 40s. Locations south of a line from Petersburg
WV to Charlottesville have the greatest chance for some sun and
highs rising into the 50s. Cloud cover will further increase
Saturday night, though lows may still be able to reach the upper
20s and lower 30s.
Ridging will be in place aloft Sunday and Sunday night as the
next low pressure system approaches from the mid Mississippi
Valley. Some showers will be most probable across the northern
half of the area, closer to vorticity advection and the warm
frontal zone aloft. While wind direction will technically be
southerly, low clouds may remain in place beneath an inversion
as the mid levels warm faster than the low levels. Highs in the
50s may be ambitious, with 40s more likely across much of the
area. Temperatures won`t drop much Sunday night as the cold
front remains to the west.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
Next week begins with a pair of upper lows in the vicinity of the
Canadian Maritimes held in place by ridging over Greenland. Over the
CONUS, brief/transient ridging will be in place along the East Coast
ahead of a deepening trough over the Great Lakes and Midwest. This
trough will dig toward the Mid-Atlantic as ridging pokes into the
western CONUS downstream of a deep upper low over the Gulf of Alaska.
The approaching trough and associated surface frontal system will
have its forward progress slowed thanks to the blocky pattern
downstream over the North Atlantic. Eventually, the trough merges
with the upper lows over the Canadian Maritimes carving out a deep
trough over the eastern CONUS heading into the middle of next week.
Milder air ahead of the trough/front will result in rain showers
into the day on Monday. Following the front, winds will increase as
cold air rushes in late Monday through Tuesday. Given the amplified
pattern, strong pressure gradient in the amplified flow, and strong
cold/dry advection, wind gusts could feasibly exceed 40 mph for a
good portion of the area (especially at higher elevations). This
will drive wind chills into the teens and 20s Monday night, perhaps
as low as the single digits to around 10 below zero over the highest
peaks of the Alleghenies. Depending on how much moisture is left and
the exact wind direction in the wake of the early weak front, some
upslope snow is possible.
Most of the second half of next week looks mainly dry. Another front
may slide through mid week, perhaps aiding in a few snow showers
over the mountains if enough moisture is to be had. Otherwise,
December will end just as it started - colder than normal.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
Precipitation with today`s event has generally trended later
(most notable precipitation during the late afternoon and
evening) and lighter. IAD/DCA could see some sleet pellets
around the onset but may largely just see some light rain
showers/sprinkles. While BWI/MTN/MRB most likely see
precipitation, some in the form of sleet and possibly freezing
rain, they also may rise/remain just above freezing and preclude
too much impact. CHO may not see much precipitation at all. Most
guidance doesn`t lower ceilings until this evening. Wind
direction starts the day northeasterly but will swing around to
the southeast or south by late afternoon.
In the wake of this event tonight, MVFR to IFR ceilings likely
continue, except at CHO. Winds turn back to northerly as low
pressure moves off the coast and high pressure builds in from
the north. Ceilings should improve Saturday, except at
BWI/MTN/DCA, where a more northeasterly wind could provide some
drizzle at times. Gusts to around 20 kt are also possible at
these terminals Saturday.
A prolonged period of sub-VFR ceilings is possible from Saturday
night through Sunday night. Some improvement is possible during
the daytime hours, with CHO having the highest chance of
reaching VFR. Some rain showers may cross at times Sunday and
Sunday night but shouldn`t be too heavy. Winds become southerly
Sunday, with some gusts to 20 kt possible Sunday night.
Sub-VFR conditions likely linger well into Monday with rain showers
around. Gusty W/NW winds and a return to VFR are expected late
Monday into Tuesday. Gusts could exceed 30 knots during this
time.
&&
.MARINE...
North to northeast winds are resulting in advisory conditions
south of the bay bridge early this morning. These winds should
diminish shortly after sunrise. The northern waters could see a
wintry mix this afternoon into the early overnight hours. By
late tonight, a shift to northerlies is expected with some
channeling effects possible at times over the wider waters of
the Chesapeake Bay. Small Craft Advisories may be needed for
this surge during the day Saturday. High pressure will provide
lighter winds Saturday night.
Southerly winds stay below SCA criteria throughout the day on
Sunday, before increasing overnight as a low pressure system
approaches from the west. Advisories will likely be needed.
Southerly flow channels ahead of a strong front through early Monday
with gusts around 25 knots likely. Strong cold air advection will
result in blustery conditions in the wake of a front late Monday
into Tuesday, with gales possible.
&&
.TIDES/COASTAL FLOODING...
Some locations may reach action stage tonight as low pressure
moves off the coast. Annapolis will come closest to minor flood.
After a brief dip in northerly winds Saturday, tides will
rebound in southerly flow Sunday into early Monday. Annapolis
may near the minor flood threshold again.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Winter Weather Advisory from 2 PM this afternoon to 3 AM EST
Saturday for MDZ008-507-508.
Winter Weather Advisory from 10 AM this morning to 11 PM EST
this evening for MDZ003-502.
Winter Weather Advisory from noon today to midnight EST
tonight for MDZ004>006-011-503-505-506.
Ice Storm Warning from 8 AM this morning to 1 AM EST Saturday
for MDZ501-510.
Winter Weather Advisory from 8 AM this morning to 7 PM EST
this evening for MDZ509.
VA...Winter Weather Advisory from 10 AM this morning to 11 PM EST
this evening for VAZ027-028-030-031-507.
Winter Weather Advisory from noon today to midnight EST
tonight for VAZ505.
WV...Winter Weather Advisory from 10 AM this morning to 11 PM EST
this evening for WVZ050>053-055-502>504.
Winter Weather Advisory from 8 AM this morning to 7 PM EST
this evening for WVZ501.
MARINE...Winter Weather Advisory from 2 PM this afternoon to 3 AM EST
Saturday for ANZ530.
Small Craft Advisory until 7 AM EST this morning for
ANZ531>534-537-539>541-543.
&&
$$
SYNOPSIS...DHOF
NEAR TERM...ADS
SHORT TERM...ADS
LONG TERM...DHOF
AVIATION...ADS/DHOF
MARINE...ADS/DHOF
TIDES/COASTAL FLOODING...ADS
NWS LWX Office Area Forecast Discussion