181
FXUS61 KCTP 210546
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1246 AM EST Fri Nov 21 2025

.SYNOPSIS...
* Mostly cloudy skies continue through Saturday morning
* Period of light rain later Friday through Friday night
  precedes a drying trend with more sunshine over the weekend
* Mild pattern with rain prior to Thanksgiving turns decidedly
  colder with temperatures below average by next weekend

&&

.NEAR TERM /UNTIL 7 AM THIS MORNING/...
Cloud deck has consumed the entire CWA and is low enough to
touch the ridge tops. Drizzle is falling here and there, mainly
in the SW quarter of the CWA right now. Forcing is so weak that
it is tough to pick out the mechanism generating it. However,
the NAM does have a bead on it, and slides the light QPF it
makes to the east slowly tonight. Have added areas of DZ and FG
to most of the area. The conditions may get worse overnight
(vsby) but they won`t get any better. We will consider a dense
fog advy if the vsby creeps lower than the ridge tops.
Thankfully, unlike last night, the temps and dewpoints are
above freezing and no black ice/freezing fog is expected to
form. Temps will waggle within a couple of degrees of current,
and may even rise a tiny bit in some places.

&&

.SHORT TERM /7 AM THIS MORNING THROUGH 6 PM SATURDAY/...
Will see what the new guidance gives in a coule of hours, but we
may need to add some PoPs to the NW for Fri AM/early aftn as the
short wave trough passing over Lower ONT generates a few/isold
SHRA over wrn NY. A couple could dip into NW PA (at the same
time the srn rain is trying to sneak in).

Prev...
Split stream flow aloft eventually sends a cold front through
CPA to end the week, driving a period of rain most likely from
late Friday afternoon through Friday night/AM Saturday. Earlier
in the week, we were watching the tilt and strength of an upper
trough drifting across the Great Lakes as a signal for how much
rain would fall. The trough has trended weaker and less
negatively tilted, which will lead to a lack of phasing with the
surface low and an overall lack of strong forcing. As such, QPF
has continued to trend lower. The heaviest rain will fall across
the southern tier and several models now keep rain suppressed
entirely south of the Turnpike/I-76. Some pockets of mixed
precip may be possible on the northern edge of the precip by
early Saturday morning, but the southward suppression of QPF
would render this precipitation type uncertainty a moot point.
Max temps Friday bounce 5-10F to the upside reaching the 45-55F
range.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Drying trend expected over the weekend behind the cold frontal
passage. Upper level trough pivoting through the Great Lakes may
deliver some rain/snow showers to the northern tier on Sunday.
On balance, it should be a quiet weekend with temps remaining
close to the historical average. We`ll see much more sunshine
later Saturday through Monday, which will be a welcome change.
Sunday morning is the coldest morning of the week ahead, with
partly cloudy skies supporting lows in the 20s.

A storm system will move through the eastern US toward the
middle of next week. While the exact timing remains uncertain
(typical fast/low biases evident in the GFS/ECMWF), a period of
rain appears most likely in the Tuesday or Wednesday time frame
ahead of the next split stream system tracking eastward from the
Central U.S. Temperatures will be mild as the main slug of
moisture moves through, with rain as the predominant
precipitation type. Colder air wrapping around the system could
produce some snow showers in the northwest mountains late in the
week. By next week, ensemble model data continues to advertise
a pattern shift toward colder/below average temperatures after
Thanksgiving.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
Low clouds and fog will prevail much of the time overnight into
Friday morning or early aft.

Sites that can keep a bit of a breeze like JST will have the
best chance of not having as much fog.

Some showers with the cold front, but overall not much on
Friday.

A fast moving wave is likely to form along the cold front.
This wave may bring some more rain to the area Friday night,
mainly across the southern part of PA.

Outlook...

Sat...Improvement to VFR at most terminals. Fog may return Sat
night.

Sun-Mon...Mainly VFR.

Tue...Restrictions in widespread rain possible.

&&

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

&&

$$

SYNOPSIS...Steinbugl/Banghoff
NEAR TERM...Dangelo/Banghoff
SHORT TERM...Steinbugl/Banghoff
LONG TERM...Steinbugl/Banghoff
AVIATION...Martin