818
FXUS61 KCTP 040110
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
810 PM EST Wed Dec 3 2025

.SYNOPSIS...
* Arctic cold front brings light snow, gusty winds and travel
  impacts to the Allegheny Front late tonight-Thursday morning
* Plummeting temperatures into Thursday night with frigid to
  record challenging lows Friday morning
* Reinforcing cold pattern locks in below average temperatures
  through the second week of December

&&

.NEAR TERM /THROUGH THURSDAY/...
An arctic cold front will plow southeast across the Lower Great
Lakes late tonight and reach northwest PA by early Thursday
morning. Light snow/snow showers with minor accum (generally
<1") will accompany the front over the western Allegheny Front
(particularly along and west of Route 219) and could spill as
far east as the I99 corridor into the peak morning commute.
We issued a SPS in coordination with PBZ and LWX to highlight
possible (sub-advisory level) travel impacts/disruptions.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
Arctic front sweeps through CPA Thursday morning exiting the
Lower Susq Valley by 18Z/1PM. Frontal lift combined with
orographics and increasingly cold NW flow downwind of Lake Erie
favors persistent snow showers over the NW mtns and Laurel
Highlands through the morning hours.

Snow squall risk is still in-play to some extent with potential
for linear development along the arctic front; however the best
signal remains pegged to the north of CPA in update NY. So
overall confidence remains low, but threat is non-zero.

Fcst snow amounts over the western high terrain remain light
(1" or less) with locally higher amounts up to 2" possible in
the favored lake effect belt in Warren County and ridgetop ski
resorts in the Laurel Highlands.

Temps will plunge behind the arctic front as blustery NW flow
sends readings falling NW->SE by Thursday afternoon. High
pressure building over CPA will decrease the wind Thursday
evening, setting up a frigid night with record challenging min
temps fcst in the single digits to lower teens (15-20F below
the historical average). It won`t take much wind to drop wind
chills below zero especially over the western mtns as gradient
picks back up by Friday morning.

Quite cold, mid-winter feel to end to the week with fcst highs
below the freezing mark in most of the CWA.

Low amplitude, jet-induced low pressure system tracking well south
of PA and developing off the NC coast could brush the southern
tier of CPA with light snow on Friday. Latest NBM probs for >1"
are generally less than 30% for areas south of the PA Turnpike
(slightly higher toward 50/50 odds southeast of US-30 from
Chambersburg to Lancaster). This could impact travel early
Friday so we will continue to monitor; but for now the most
likely outcome is for snow accum to stay south of the MD line.
Weak sfc ridging Friday night holds low cloud cover beneath
the subsidence inversion with min temps trending 5-15 degrees
warmer vs. Thursday night (albeit from near record lows!).

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Series of reinforcing shortwaves offer opportunities for snow
late in the weekend and early next week; however the main theme
in the long term will be the cold pattern with below normal
temps expected to last through the second week of December.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
Stratus with MVFR or lower cigs will persist over the NW
mountains and Laurels (BFD and JST) for much of tonight. UNV and
IPT are right on the edge of the stratus deck, and thus lower
confidence for MVFR conditions (both VFR as of 01z). Latest
satellite imagery also shows a bit of clearing around JST, but
much of the model guidance shows a trend towards IFR and even
LIFR by 06z Thu with the potential for light freezing drizzle or
flurries from that point until cold FROPA Thursday morning.

Main issue for late tonight into Thursday will be the passage of
a strong cold front. This will bring the potential for heavy
snow showers, mainly at BFD and JST, but perhaps also into UNV,
AOO, and maybe IPT between late tonight and mid day Thursday.
The cold air and low level moisture is not real deep, but the
airmass behind the front is abnormally cold, which has the
potential to compensate by providing low level instability.
There is also some potential for marginal LLWS right ahead of
the cold FROPA, but in general the shear will be dissipated by
mechanical mixing via wind gusts.

The weather for Friday into Monday will feature weather systems
to the southeast and northwest of our area, so while low CIGS
and snow showers may prevail at times, not seeing any big storms
at this point.

Outlook...

Fri...Cold start to the day with temps 0-15F. Slight chance of
light snow across the southern half of central PA with
restrictions possible.

Sat-Mon...Restrictions possible, chance of snow showers in the
NW.

&&

.CLIMATE...
Cold temperatures in the wake of the Arctic Front will bring
frigid temperatures to central Pennsylvania, the coldest of this
winter thus far. Multiple locations across the area will be
challenging record low temperatures on December 5th:

Location|Record
Harrisburg | 12 (1926)
Williamsport |   8 (1926)
Bradford | 0 (2007)
Altoona | 13 (1966)

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Steinbugl
NEAR TERM...Steinbugl
SHORT TERM...Steinbugl
LONG TERM...Steinbugl
AVIATION...Martin/Colbert
CLIMATE...NPB