340
FXUS61 KLWX 230844
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
344 AM EST Tue Dec 23 2025

.SYNOPSIS...
A warm front will lift into the area today, with a cold front
following this evening. Another transient area of high pressure on
Wednesday may give way to a warm front Thursday. A cold front
will push through Thursday night and stall to the south, with a
wave of low pressure riding along the boundary Friday. A
stronger cold front arrives toward the end of the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
High pressure is moving offshore this morning while low pressure
moves toward Lake Superior. Several bands of precipitation
extend across the warm advection regime ahead of the low.
Interestingly, the coldest air in the forecast area is along the
ridges in Highland and southern Pendleton Counties, and to an
extent the Blue Ridge. While models have been suggestive of
cold air getting hung up in this area, the steady warm advection
regime hasn`t been quite as effective as progged. With that
said, it is a matter of time, and most valley locations are
right at to a few degrees above freezing. Thus think the Special
Weather Statement should be sufficient to cover any light
freezing rain since precipitation is light and intermittent
with only localized freezing temperatures. Some cold air also
lingers across northeastern Maryland, but most observations have
been largely trending above freezing. So far, most obs of
precipitation reaching the ground have been rain. Suppose there
could still be some snow or sleet especially across northeastern
Maryland, but little to no accumulation is expected. There is
still plenty of low level dry air, so precipitation will be
light in nature. With current hydrometeors serving to saturate
the low levels, most models still show the main push of any
measurable rain (less than a tenth of an inch, except higher
amounts west of the Allegheny Front) between 5 AM and noon. Will
be monitoring for any wet bulb effects which may pull
temperatures below freezing. However, the light nature of the
precipitation won`t be efficient for accomplishing this, and the
ongoing warm and moisture advection may win out.

There`s some uncertainty with how quickly/how much clouds can
clear out today. They will hang around longest across northern
and western parts of the area (where upslope rain showers will
continue in the Alleghenies). The clouds will have a large
impact on temperatures, not to mention how much low level
saturation occurs from precipitation. The coolest readings in
the 40s are expected in north central/northeast Maryland, with
an eventual increase to near 60 across the central Shenandoah
Valley and central Virginia.

A low level jet will also increase as the trough axis
approaches. The higher elevations along the Allegheny Front may
approach Wind Advisory criteria today into this evening, but
the low levels will be stable and relatively saturated, so less
wind is expected in the lower elevations.

The associated cold front eventually moves through by this
evening. Dry advection will follow the front, but not much cold
advection as ridging and a warm airmass remain over much of the
nation`s mid section. Low temperatures will only drop to the
30s to lower 40s.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Surface high pressure will build in from the west on Wednesday. Dry
weather is expected, but mid and high level clouds will start
to increase in the afternoon. A thermal gradient will remain
across the area, with another wide range of highs from the mid
40s to near 60 expected.

The next shortwave trough and area of isentropic lift will approach
the area Wednesday night. There`s still uncertainty with how
much and how quickly any precipitation will spread eastward,
with chances increasing the second half of the night into
Thursday morning. There`s a low end potential that if the
precip catches up to residual cold air in northeastern Maryland
that it could be wintry, but this seems like an unlikely
scenario at this time. Most of the area will have temperatures
safely above freezing, even in the mountains. A weak surface low
may draw a warm front into the area Thursday, but it may not
make it entirely through. Thus, temperatures may again range
from the mid 40s north to near 60 south. Any showers should end
by afternoon as the wave passes, except for some lingering
upslope rain showers in the Alleghenies.

There will be a stronger low moving through Quebec with a
strong area of high pressure in its wake. This will push the
composite front south of the area Thursday night with colder and
drier air arriving in its wake. How exactly this unfolds will
set the stage for the next system Friday.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
After a significant shift southward with a disturbance 12-24 hours
ago, model guidance has somewhat settled in for the time being on
the overall track of this system. To explain how drastic of a shift
this was, the NBM at IAD 24 hours ago had a high of 66 on 12/26. The
latest NBM has a high of 36. Some guidance that has yet to make it
into the NBM has highs not making it above freezing for the northern
half of the FA Friday. As a result, many solutions now show wintry
precipitation across the northern half of the forecast area (roughly
I-66/US-50 northward). Of the solutions that do have wintry
precipitation, most favor freezing rain and sleet, but some snow
can`t be completely ruled out depending on the ultimate track of the
system. Further shifts in storm track are likely as this disturbance
moves into better sampled areas of the Pacific Ocean/West Coast.

The aforementioned system will progress off to our east by Saturday,
leading to drier conditions locally. A much deeper closed upper
level low is expected to approach from the northwest on Sunday,
potentially leading to the next chance for rain. A very strong
Arctic front will likely move through later Sunday into Sunday night
as the system departs. Windy and much colder conditions are expected
by Sunday night, with precipitation potentially ending as a little
upslope snow in the mountains into Monday.

&&

.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
Several bands of light precipitation are moving across the area
this morning ahead of a warm front. Based on observations and
modeled thermal profiles, most terminals will just see light
rain. There is still some potential for a bit of snow to mix in,
mainly near MTN. The light nature of the precipitation and dry
low levels will likely preclude much in the way of
ceiling/visibility reductions until the precipitation ends
around mid morning. The best chance of MVFR ceilings into the
afternoon appears to be at MRB, BWI, and MTN. A cold front
crossing late this afternoon into the evening will shift
southerly winds to westerly and likely clear out any lower
ceilings, although some clouds may linger into the night.

VFR conditions are expected with high pressure on Wednesday,
although northwesterly winds may gust to around 20-25 kt through
the first half of the day. Clouds may begin lowering with
chances of rain increasing the second half of Wednesday night
into Thursday morning as a warm front and wave of low pressure
approach. MVFR ceilings are most probable Thursday, although
any rain showers will likely be light. It appears conditions
will improve Thursday night as a cold front passes.

A wintry mix could bring sub-VFR conditions Friday with a mixture of
precipitation types possible along with accumulating wintry precip
(most likely freezing rain at this time). Precip could linger into
early Saturday, with clouds persisting (likely above any
restrictions). Winds look relatively light, and direction is a bit
uncertain at the moment, but consensus favors easterly winds Friday
and northeasterly winds Saturday.

&&

.MARINE...
A Small Craft Advisory remains in effect for much of the
Chesapeake Bay and lower Potomac this morning. South winds of
10 to 15 kts are expected with gusts up to 20 kts at times.
Winds diminish below SCA levels this afternoon. A cold front
will push through this evening, shifting winds to the west and
eventually northwest. Additional SCAs will likely be needed
late tonight through Wednesday afternoon with gusts of 20-25
kt. High pressure settles overhead late Wednesday, providing
lighter winds.

A wave of low pressure will pass through the area Thursday.
Brief and marginal advisory conditions could occur in southerly
flow on Thursday, and then in northerly flow behind the
associated cold front Thursday night.

Sub-SCA level winds appear likely on both Friday (easterly) and
Saturday (northeasterly).

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until noon EST today for ANZ531-532-539-
     540.
     Small Craft Advisory until 3 PM EST this afternoon for ANZ533-
     534-537-541-543.

&&

$$

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