171
FXUS61 KLWX 240800
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
300 AM EST Tue Feb 24 2026
.WHAT HAS CHANGED...
Winter Weather Advisories have been issued for the western favored
slopes of the Alleghenies later this evening through Wednesday
morning. Widespread precipitation chances return Thursday with a
lower confidence on winter weather impacts late Thursday afternoon
into Friday morning as the storm system departs.
&&
.KEY MESSAGES...
-1) Upslope snow showers diminish over the mountains this morning.
Winter Weather Advisories have been issued for additional
accumulating mountain snow late tonight into Wednesday morning.
-2) A wave of low pressure will bring widespread precipitation
chances to the area Thursday into Thursday night.
-3)After a dry and seasonable start to the weekend, another low
pressure system may affect the area early next week.
&&
.DISCUSSION...
KEY MESSAGE 1...Upslope snow showers diminish over the mountains
this morning. WInter Weather Advisories have been issued for
additional accumulating mountain snow late tonight into Wednesday morning.
Special Weather Statements have been issued for residual scattered
snow shower activity over the western slopes of the Alleghenies
this morning. An additional coating to perhaps 2 inches of snow is
possible at elevations above 2000 feet. This activity should diminish
by daybreak with a brief lull for the afternoon and evening hours.
Winter Weather Advisories have been reintroduced to the western Alleghenies
(i.e Garrett, western Grant, western Pendleton, and western Highland counties)
from 03z-15z/10pm tonight-10am Wednesday. Accumulations of 3 to 6 inches are
possible with locally higher amounts pending any heavier rates during
the predawn period Wednesday morning when the bulk of the snow will fall. Snow
ratios won`t be all that impressive running between 10:1 to start increasing to
12-13:1 during the the event. This will yield a wet snow with
average QPF between 0.30-0.50 inches. A light glaze of ice is
also possible in the cold air drainage along the eastern slopes
of Garrett down into Pendleton counties (mainly above 2500
feet) as temps warm Wednesday morning. Plan for additional
travel disruptions along I-68/US-40 west of Frostburg, MD,
US-219 from the PA/MD line to WV line, US-48 west of Moorefield,
WV, and US-33/WV-28 west of Franklin, WV. Some spillover is
possible to the east although FROUDE numbers will increase from
0 to 3 during the event leading to predominantly blocked flow.
Elsewhere, a few rain/snow showers cannot be ruled out, mainly north of I-66/US-50 where
the better lift resides. Any snow accumulations will be confined to the Catoctins,
Parr`s Ridge, and locally high spots along the PA/MD border where a light
coating of snow is possible. Confidence in this is low with main lift/moisture source
remaining north/west of the area.
Dry conditions are expected today outside of the precipitation threat tonight.
Highs today will range from the upper 20s and low 30s across the mountain/PA/MD
line to low 40s in the central VA. Lows tonight will fall into the upper 20s
low 30s outside the mountains with increased cloud cover. Expect decreasing winds
as well with gusts 15 to 20 mph this afternoon. Wind chills this morning will be
at or below zero over the mountains with single digits and teens to the east. These
values improve into the 30s (teens mountains) this afternoon.
KEY MESSAGE 2...A wave of low pressure will bring widespread
precipitation chances to the area Thursday into Thursday night.
Drier conditions return Wednesday with a cold front set to cross
late Wednesday afternoon into Wednesday evening. Meanwhile, a fast
moving area of low pressure will drop south in northwesterly flow
across the Midwest and Ohio Valley Wednesday night, before tracking
eastward near the local area Thursday into Thursday night. This
system will be a bit stronger, and will have more moisture to work
with compared to the Tuesday night/Wednesday system.
Spread amongst model guidance still remains high although many
ensemble/deterministic solutions are now favoring a soaking rain
compared to any wintry precipitation across the forecast region. For
instance, the probabilities of at least 0.01" of freezing rain
yesterday were around 20 to 30 percent across areas north of I-66/US-
50. Guidance this morning has dropped those probabilities to less
than 15 percent. Similar probabilities have also been noted for
snowfall.
Current 00z guidance still varies on the placement of a stalled
boundary to the south and high pressure to the north. The stalled
boundary will act as a track for the low as it ejects from the Mid-
South into the central/southern Apps and eventually off the
Carolinas/coast of VA. American guidance is leaning toward a low
over the central Apps moving toward the VA/NC coat while the
European/Canadian guidance is further south. Overall looking at a
progressive system with beneficial precipitation to eat away at
current drought concerns. A general 0.25-0.50" of precipitation is
likely with higher totals over the Alleghenies. Some localized
runoff/nuisance flooding is possible, especially over the terrain
given the added snowpack.
KEY MESSAGE 3...After a dry and seasonable start to the weekend,
another low pressure system may affect the area early next week.
Thursday`s frontal system should be exiting to the southeast Friday
morning. Clearing skies and seasonable temperatures can be expected
in its wake. High pressure will build overhead Friday night and push
to the south and east Saturday, allowing for a further warming
trend. Meanwhile, low pressure will be passing well to the north in
Canada, sending a cold front toward the area Sunday. This front may
initially pass through dry. Strong high pressure will be building to
its north, drawing colder air toward the area. However, model spread
increases appreciably during this time, both in temperatures and how
the next trough will evolve. If a system were to line up with colder
temperatures, some wintry precipitation could occur early next week.
Right now, chances are fairly low given the disparate model
solutions, but it is a period worth monitoring.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
VFR conditions are expected at all terminals through Wednesday.
Winds will remain elevated out of the west/northwest this morning
into midday with gusts between 20 to 30 kts outside of KCHO. Winds
will diminish later this afternoon into tonight while slowly
switching to a southerly direction with gusts less than 15 kts.
SOme temporary sub-VFR conditions are possible from light rain/snow
showers working east of the mountains late tonight into Wednesday
morning as a warm front lifts into the region. Did add PROB30s in
the corridor although confidence is low for 4-6SM -SN between 07-
15z/2a-10am. The bigger concern to aviator will be LLWS. Hi-res CAMS
and soundings show this with southerly flow during the 06-13z/1am-7am
Wednesday timeframe. Did include this at all the core terminals
within the corridor outside of KCHO where confidence was lower.
Winds will shift to the south with the front with gusts 15 to 20 kts
Tuesday night into Wednesday.
Next chance of sub-VFR conditions arrives Thursday into Thursday
night as low pressure bring widespread RA to the region. Winds will
switch from the south back to the east and northeast as low pressure
passes to the south. Gusts will remain less than 15 kts.
VFR conditions are expected to return Friday and Saturday as high
pressure builds into the area.
&&
.MARINE...
Small Craft Advisories are in effect through midday across all
waters as gusty northwest winds continue. Winds quickly diminish
later this afternoon and evening dropping below Small Craft Advisory
criteria.Northwest winds shift to southerly this evening with
southerly channeling leading to additional Small Craft Advisories
tonight through Wednesday afternoon. Southwest winds become light
and variable Wednesday night. Small Craft Advisories are possible in
E/SE flow becoming W/NW as low pressure passes late Thursday. Rain
is likely Thursday, as well.
Wind speeds should trend downward Friday as high pressure builds
into the area. Wind direction will flip from northwest Friday to
south by early Saturday.
&&
.TIDES/COASTAL FLOODING...
Offshore flow will maintain below normal water levels through this
morning`s tide cycle. Southerly flow this evening will result in
rising water levels that could push minor flooding thresholds,
especially at Annapolis. In fact, some of the more aggressive
guidance brings Annapolis close to moderate flood stage, but the
brevity of favorable flow should keep any flooding that occurs below
this level.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 4 PM EST this afternoon for MDZ008.
Winter Weather Advisory from 10 PM this evening to 10 AM EST
Wednesday for MDZ509-510.
VA...Winter Weather Advisory from 10 PM this evening to 10 AM EST
Wednesday for VAZ503.
WV...Winter Weather Advisory from 10 PM this evening to 10 AM EST
Wednesday for WVZ501-505.
MARINE...Small Craft Advisory until 4 PM EST this afternoon for
ANZ530>543.
&&
$$
DISCUSSION...EST
AVIATION...ADS/EST
MARINE...ADS/EST
NWS LWX Office Area Forecast Discussion