790
FXUS61 KCTP 261207
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
707 AM EST Wed Nov 26 2025

.SYNOPSIS...
* Cloudy and damp with light showers across the Northwest Half
  of PA and areas of dense fog in the southeast early today
* A strong cold front will bring a few additional showers later
  this morning and this afternoon, followed by strong gusty
  winds and much colder temps tonight through Friday
* Lake effect snow may result in significant Thanksgiving
  holiday travel disruptions across northwest Pennsylvania,
  while scattered snow showers and a few squalls impact the
  weather across the Central Mtns, Laurel Highlands and possibly
  the Middle Susquehanna Valley Thursday into Friday

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Weak llvl warm advection and the presence of a 95 kt jetlet at
300 mb lifting NE across Wrn and Central PA was supporting
plenty of clouds and numerous, albeit light rain showers through
the predawn hours.

SFC cold front was pushing into Western Ohio attm and will move
across PA during the late morning and afternoon hours, with
another brief/gusty shower mainly over the Western half of the
CWA.

Elsewhere this morning, Foggy conditions with vsbys varying
between 1/4-1/2SM will persist for the next few to several
hours and will be under a Dense Fog Advisory through 13Z today.
The fog formed yesterday evening as a result of significant
breaks in the cloud cover and radiational cooling near, and just
to the north of a slow-moving warm front where llvl moisture was
pooling.

Forecast high temperatures today will be very mild for late
November (ranging from the low to mid 50s across the Northern
and Western Mtns to the low and mid 60s in the southern Valleys

These values could end up being several deg F too high if the
fog lingers longer than expected. This cold front will usher in
much colder air for tonight through Friday.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
Model soundings show the potential for widespread wind gusts
tonight and Thursday morning in the 40 to 55 mph range as winds
at the top of the mixed layer approach 50 knots and the 40 kt
isotach is noted more than half of the way to the ground from
the 4-5 kft top of the mixed layer.

Confidence is highest in the Laurel Highlands, so a Wind
Advisory remains in effect from 00z Thu to 00z Fri. The Wind
Advisory was expanded over the past few hours to include
Clearfield County which contains the heavily traveled I-80 and
where the interstate reaches its highest peak east of the
Mississippi.

Gusty winds continue into Friday, perhaps just a little less
windy than Thursday.

The main focus for this period is still the potential for heavy
lake effect snow across northwest PA. While the low-level flow
will initially be out of the southwest, favoring areas north of
the Pennsylvania-New York border for the heaviest snow, winds
quickly become more westerly by Thursday morning, directing the
snow bands into northwest PA.

Most guidance shows the flow remaining favorable for snow to
continue over northwest PA through Friday. With confidence
continuing to increase in at least portions of Warren and McKean
counties seeing from 6 to 12+ inches of snow, we have upgraded
the Winter Storm Watch to a Lake Effect Snow Warning. Areas that
see the most persistent snow bands may even see snowfall
amounts as high as 15 to 18 inches (if they sit beneath a true
LES band for a several hours where snowfall rates could be in
the 2-3 inch per hour range.

Heavy snow combined with wind gusts up to 40 mph may make
travel difficult to impossible at times. Lake effect snow bands
will almost certainly make it farther south and east than those
two counties, but confidence in placement and snowfall amounts
remains too low to issue any Winter Weather Advisories yet.

Snow showers will also impact the Western Mountains
tonight/Thursday and again on Friday with model RH profiles
showing saturation in the DGZ along with favorable upslope wind
trajectories. Friday may also feature a few snow showers or
squalls that could impact the the I-80 and I-99 corridors,
leading to rapidly changing travel conditions.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
The lake effect snow pattern comes to an end Saturday morning as
low-level flow backs and high pressure begins to build in,
resulting in a lowering subsidence inversion. There is still
some uncertainty with speed/timing, but overall guidance agrees
in returning precip to the area on Sunday. Thermal profiles
appear to be cold enough to initially support snow, then perhaps
mixing with or changing to rain for the last day of November.
Unsettled weather will continue into early next week as cold air
in the middle of the country sets up a strong baroclinic zone
over the eastern US.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
LIFR in fog currently locked in the southeast corner of the
forecast area but this will dissipate in the next hour or so as
winds increase aheads of an approaching cold front. Scattered
-SHRA ahead of this front will move across the central portions
 of the state through the morning with isolated MVFR.

As the day progresses, conditions will gradually become VFR
elsewhere. Along and behind the front, winds will become
westerly (240-280 degrees) and it will turn quite blustery.

Blustery westerly winds will continue overnight. As colder air
continues to filter into the region, snow showers will develop
across the western highlands (BFD/JST) but will occur near the
end of the forecast period and poiints beyond.

Outlook...

Thu-Fri...Windy with gusts 30-35kt from 270-300 degrees;
frequent snow showers/squalls across the NW 1/2 of the
airspace.

Sat...Improving conds; diminishing winds with lingering snow
showers ending.

Sun...Light rain/wintry mix developing from west to east;
restrictions possible.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Lake Effect Snow Warning from 1 AM Thursday to 1 AM EST
Saturday for PAZ004-005.
Winter Weather Advisory from 7 AM Thursday to 1 AM EST
Saturday for PAZ006-010-011.
Wind Advisory from 7 PM this evening to 7 PM EST Thursday for
PAZ017-024-025-033-034.
Dense Fog Advisory until 8 AM EST this morning for PAZ036-
057>059-063>066.

&&

$$

SYNOPSIS...Lambert/Colbert
NEAR TERM...Lambert/Colbert
SHORT TERM...Lambert/Colbert
LONG TERM...Colbert/Bauco
AVIATION...Tyburski