262
FXUS61 KLWX 170218 AAA
AFDLWX

Area Forecast Discussion...UPDATED
National Weather Service Baltimore MD/Washington DC
918 PM EST Fri Jan 16 2026

.WHAT HAS CHANGED...
No changes to current hazards (Winter Weather Advisory and Small
Craft Advisory). Snow totals bumped up slightly across north to
northeast MD for Saturday morning, with a dusting possible in
some other areas. Higher snow totals look to remain east of the
area Sunday, with a dusting along I-95 and possibly up to an
inch in far southern MD.

&&

.KEY MESSAGES...
- 1) An Arctic outbreak is likely early next week, with near to
  below normal temperatures continuing through the remainder of
  the week.

- 2) Multiple disturbances will bring snow to parts of the area
  tonight through Sunday.

&&

.DISCUSSION...
KEY MESSAGE 1...Multiple disturbances will bring snow to parts
of the area tonight through Sunday.

Temperatures have been slowly rising this evening, and in fact,
are the warmest they had been all day. Expect slowly rising
temps overnight due warm air and moisture advection as a warm
front lifts through the area. This decreases the chance of snow
east of the mountains south of I-70. Latest AIFS and EPS
guidance show a downward trend in snow accumulation across
northeast MD through Saturday morning. So not contemplating any
advisories for northeast MD. Across western MD, snow has begun
in the past hour with 2G4 and CKB now reporting snow. Also,
snowfall rate product from a MetOp-B pass at 0132Z showed snow
falling across much of WV and western MD with snowfall rates of
up to quarter inch per hour.

Previous afd...

An upper trough elongates across much of the eastern CONUS this
weekend, with numerous shortwaves traversing the Mid-Atlantic
tonight through Sunday. An associated surface low develops along or
just off the Carolina coastline late Saturday, then pushes offshore
by Sunday night. An arctic cold front crosses the region at the end
of the weekend.

An initial surge of moisture and lifts associated with weak WAA
ahead of the main trough arrives tonight in the Alleghenies. Given
the very cold temps at onset, this event is going to remain all snow
in the mountains with snow beginning this evening. The continued low
FROUDE numbers and a WSW/SW low-level wind flow will focus the bulk
of the precip/lift/snow in far western Grant and western Garrett
Counties. There will be some spillover into western
Pendleton/Highland but the nearby higher terrain will block most of
the precip. Not much change in the model QPF guidance, so will keep
the 2-5" of snow in the Winter Weather Advisory area that begins
late this evening. Elsewhere, a dusting to possibly one inch of snow
is possible through Saturday afternoon. Model soundings indicate the
heaviest bursts of snow will occur Saturday morning when the best
lift is within the DGZ. Hazardous travel conditions expected in the
affected area, with periods of very low visibility with blowing snow.

To the east of the mountains, we are monitoring the possibility for
light snow Saturday morning as a prefrontal shortwave lifts through
the area. Surface temps are marginal east of the Blue Ridge and
south of US-50, plus any precip is going to have to overcome the
very dry surface airmass (dew points in the upper teens to low 20s
Saturday morning). So any snow that falls in this area is likely to
quickly melt. Elsewhere, the light snow could produce a dusting on
grassy or elevated surfaces. The best chance for accumulating
snowfall is going to be in the Catoctins and in north/northeast MD.
12Z high res guidance from this afternoon increased our confidence
in seeing some snow accumulate in this area, though it still has to
overcome the marginal temps and dry air. Those from Parr`s Ridge to
the MD/PA border and Catoctins could see an inch of snow.

Snow turns to rain/snow mix, then all rain by early afternoon as
temps climb to the upper 30s to mid 40s. Any snow that falls is
going to quickly melt with more sunshine also expected. Southwest
winds gust around 20-25 mph at this Saturday afternoon.

For Sunday, a stout shortwave rounding the base of larger scale
troughing over the eastern CONUS pivots across the Deep South toward
the Carolinas Saturday night into Sunday while taking on a neutral
tilt. Precip is going to be mainly forced by the mid/upper jet,
though some low-level FGEN is possible. Most of the guidance has
coalesced around a less amplified solution on Sunday (mostly due to
a more amplified shortwave that brings us snow on Saturday). It
appears that a light snow / flurries are possible east of the Blue
Ridge, with any accumulating snowfall most likely from the
Fredericksburg area to Southern MD - and then we are still talking
about a few tenths of an inch to around one inch of snow.
Temperatures are forecast to be right around freezing, which will
prevent snow from accumulating unless snow rates are at least
steady.

In terms of model guidance, the GFS remains as the outlier with
higher snow totals along/east of I-95. The rest of the guidance
falls within the dusting along I-95 to 1 inch range over Southern MD.
This is where the forecast was slightly adjusted to, keeping in line
with virtually all of the ensemble guidance that has decent 1" snow
probs well east of the area. Snow comes to an end from west to east
Sunday afternoon as the coastal low pulls away. Much colder air
surges into the region Sunday night, dropping lows to the teens to
low 20s.

KEY MESSAGE 2...An Arctic outbreak is likely early next week,
with near to below normal temperatures continuing through the
remainder of the week.

Low pressure will be moving through the Great Lakes Sunday night
into Monday. Southwesterly winds will begin increasing ahead of this
system, but a residual cold airmass will remain in place. This
combination could result in wind chill values of 0 to -10 in the
higher elevations. The associated cold front will cross on Monday.
It will be a dry passage for most areas, but some snow showers with
minor accumulations will be possible along the Allegheny Mountains.
Winds will increase with frontal passage, potentially nearing wind
advisory criteria in the higher elevations. Even through the day
Monday, some of these higher elevations may keep subzero wind chill
values. Strong Canadian high pressure and an Arctic airmass will
follow the cold front. The lowest wind chill values are expected
Monday night, where cold temperatures will overlap with continued
gusty winds. Most of the lower elevations will see minimum wind
chill values of -5 to +5. Locations in the Alleghenies may
experience dangerously low wind chill values between -15 and -30.
Air temperatures are expected to stay below freezing throughout
Tuesday, although winds may not be quite as strong as Monday. The
center of the high will slide overhead Tuesday night, so winds will
be lighter at the lower elevations. However, gusty southwest winds
in the higher elevations may still create wind chills of -5 to -15.

With the high sliding off to the east, a warming trend will ensue
for Wednesday and Thursday. Even by Thursday, temperatures will
likely top out around normal. The next front will likely slide
through at the end of the week. There are some hints that a southern
stream shortwave could interact with this front and result in some
precipitation at some point. However, details are very uncertain at
this juncture, and it`s possible dry weather could just continue
through the end of the week.

&&

.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions expected through tonight as thick cirrus builds
overhead. Some rain/snow showers are possible Saturday morning
at most terminals as a disturbance moves through the area. No
accumulations expected at most terminals, though a dusting is
possible at BWI/MTN. The snow will quickly melt by early
Saturday afternoon as temps warm.

Another round of light snow is possible Sunday morning as an arctic
front crosses the area. Again, little snow accumulations are
expected at area terminals with snow chances at 30-40pct. Cannot
rule out some visibility restrictions, but looking at 4-6SM at worst.

VFR conditions return Sunday afternoon into Sunday night.

VFR conditions should largely prevail Monday through Wednesday. An
Arctic front will bring gusty west winds which will continue through
Tuesday.

&&

.MARINE...

The front moves through the local waters Saturday late morning, then
winds turn west/northwest behind the front. It is possible winds
remain elevated through early Saturday evening, then sub-SCA winds
take hold for Saturday night. An area of low pressure passes by
offshore Sunday and brings some snow or rain/snow mix, especially
over southern MD.

Wind southwest becoming northwest and gusty behind a passing Arctic
cold front Monday. Small Craft Advisories are likely in the post-
frontal airmass from Monday through Tuesday. The high passes Tuesday
night, and southwest winds could reach advisory criteria on
Wednesday.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 4 PM EST Saturday for MDZ008.
     Winter Weather Advisory until 4 PM EST Saturday for MDZ509.
VA...None.
WV...Winter Weather Advisory until 4 PM EST Saturday for WVZ501.
MARINE...Small Craft Advisory until 4 PM EST Saturday for ANZ530>534-
     537>543.
     Small Craft Advisory from 7 AM to 4 PM EST Saturday for ANZ535-
     536.

&&

$$

DISCUSSION...LFR/KRR
AVIATION...ADS/LFR/KRR
MARINE...ADS/LFR/KRR

NWS LWX Office Area Forecast Discussion