191
FXUS61 KCTP 051658
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1158 AM EST Fri Dec 5 2025

.SYNOPSIS...
* Low, non-precipitating will blanket the region through tonight
  leading to much higher, but still cold overnight lows tonight
* Light snow accumulation likely over the western and central
  Alleghenies later Sunday through Sunday night
* Reinforcing cold weather pattern and clippers provide
  additional opportunities for snow next Tuesday-Friday

&&

.NEAR TERM /THROUGH TONIGHT/...
North south axis of well-defined llvl streamline convergence is
in place across central PA and has resulted in quick nwd
advection of an extensive albeit shallow, stratus layer that
now covers practically the entire CWA late this morning.

Some additional lowering of this cloud deck will occur through
this afternoon and tonight, that will eventually intersect the
highest ridges overnight.


Previous Discussion...
Hires models and "goal-post" sounding profiles suggest that the
expanding and low cloud deck beneath a strong inversion may be
capable of producing some patchy freezing drizzle or snizzle
later today and tonight - something to monitor going forward.
The clouds may also add a few degrees to min temps currently
fcst in the 20-25F range (much warmer than this morning!)

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Passage of weak sfc trough will add a SWly breeze on Saturday
helping to push max temps closer to early December climo with
highs +5-10F warmer day/day in most locations. Lake effect snow
trajectories marginally improve by Saturday night over the NW
mtns before lowering inversion heights and backing low level
winds keep light snow accums mainly confined to the I90 corridor.

Split/northern stream trough swings through on Sunday and likely
brings some light (lake/terrain enhanced) snow primarily to the
western and northern Alleghenies. NBM snow accum favors sub-
advisory level accumulation for most areas, with the best odds
for 1-3/2-4" across the NW mtns along and north of US-6.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
A cold but quiet start to next week will be followed by a
reinforcing cold weather pattern with clippers providing
at least 2-3 opportunities for snow. Confidence remains high in
below normal temperatures; Monday night could be another frigid
period with lows -5F to +15F by daybreak Tuesday.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Stratus has spread north to cover all of the Central PA TAF
sites as of this midday hour. Ceilings will initially drop to
MVFR as these clouds move in, but most guidance continues to
indicate that further reductions to IFR are likely across most
of central PA during the evening and overnight. Once IFR
ceilings develop, they will likely persist at BFD, JST, and LNS
through the rest of the 12Z TAF period. The other sites may see
ceilings rise to MVFR before sunrise.

Model soundings show a fairly deep saturated layer below the
dendritic growth zone late this morning and during the
afternoon, which could support patchy freezing drizzle.
Confidence on this occurring remains too low to include in the
TAFs at this point.

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

Sun...A compact but more amplified upper level trough with a preceding
low level south to southwesterly wind max will likely bring a 4
to 6 hour period of mainly light snow with IFR vsbys and MVFR to
IFR CIGS (targeting mainly Central and Northern PA) late
Sunday/Sunday night.

Mon...Mainly VFR

Tue...Snow/restrictions possible mostly in the second half of
the day

&&

.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)*

** record broken
*  record tied

&&

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

&&

$$

SYNOPSIS...Lambert/Steinbugl
NEAR TERM...Lambert/Steinbugl
SHORT TERM...Steinbugl/Banghoff
LONG TERM...Steinbugl/Banghoff
AVIATION...Lambert/Bauco
CLIMATE...NPB