Area Forecast Discussion
Issued by NWS State College, PA

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189
FXUS61 KCTP 030322
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1022 PM EST Mon Mar 2 2026

.WHAT HAS CHANGED...
* Forecast on track, with a light wintry mix developing from
  southwest to northeast overnight, before gradually changing
  over to plain rain on Tuesday.

&&

.KEY MESSAGES...
1) A light wintry mix with light freezing rain accumulations
beginning overnight and continuing into Tuesday.

2) Periods of rain with temperatures running much above average
from Wednesday onward.

&&

.DISCUSSION...
KEY MESSAGE 1: A light wintry mix with light freezing rain
accumulations beginning overnight and continuing into Tuesday.

A light wintry mix will spread from southwest to northeast
across the area overnight into Tuesday morning, as a surge of
moisture is lifted over the colder/slightly sub-freezing air at
the surface. A few to several thousand ft thick layer of
slightly "above" freezing air streaming in from the southwest
will create a favorable setup for light freezing rain across
much of the region, which could impact the Tues morning
commute.

The precipitation could start as a few hour period of light
sleet and snow across the northern mountains and Susquehanna
Valley. Sub-freezing readings could last into the afternoon
hours across NE PA, which will prolong the freezing rain threat
there.

Light ice accumulation from freezing rain of generally 0.10 of
an inch or less is likely across the bulk of Central PA, with
slightly higher amounts possible on the ridges.

KEY MESSAGE 2: Periods of rain with temperatures running much
above average from Wednesday onward.

An amplifying mid/upper level ridge off the SE U.S. coast for
Wed-Fri will support a big sfc high parked off the East Coast.
These features will direct plenty of warm and moist air at the
surface and aloft northward into the region for the rest of the
week and into the weekend.

Temps are slated to be well above average, with sfc dewpoints
climbing in to the 40s and possibly lower 50s in some areas
later in the week. The W-E frontal boundary does become pretty
stationary around our latitude, but it will be wavy. There is a
possibility of a small surge of cooler air sliding down from
the NE (backdoor cold front) Friday-ish. But, by then, the temps
will be so warm that no threat exists for any wintry precip. It
should all be plain rain. Our wavy front will be the pathway
for repeated shots of forcing and constant lift, and it will be
a wet stretch of time. But, that`s not necessarily a bad thing,
considering some of the area is still in a long-term drought.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
Not a lot of change for the 00Z TAF package.

Main change was to add a line to take the mixed precipitation
to just plain rain later Tuesday aft.

VFR conditions will continue into early tonight for all but the
Laurel Highlands (near and to the south of KJST). For the north,
clear skies will continue into early tonight before high clouds
in the south begin to spread back to the north across the
state.

Winds will gradually become southeasterly to southerly for the
overnight hours. This will usher in increasing moisture at low
levels and MVFR ceilings. Low clouds will spread northward
across the rest of Central PA through the late evening and
gradually lower late tonight, likely falling to IFR for most of
the region by 12Z Tuesday.

Freezing drizzle will be possible at JST, AOO, and UNV after 04Z
as the clouds thicken ahead of a warm front lifting northward
into the region.

Steady precipitation will enter from the southwest and will
expand to the north and east through the late night hours,
likely reaching all TAF sites by sunrise Tuesday. Most of this
will fall as freezing rain, though some snow or sleet may
initially mix in, mainly to the east of UNV.

There is low potential for LLWS to develop at the western TAF
sites towards the end of the 12Z period as southwesterly winds
at 2000 feet increase to around 40 knots, but we will keep it
out of the TAFs for now as it appears to fall just short of
criteria for now.

Outlook...

Wed-Sat...Restrictions at times in periods of rain.

&&

.CLIMATE...
It was a very dry meteorological winter (Dec-Jan-Feb).
Some of our long-term climate stations cracked the top-ten of
their driest winter seasons (Dec 1st-Feb 28/29th).

Station        Total Precip    Rank    Period of
                 (inches)    (Driest)  Record (since)
------------   ------------  --------  --------------
Altoona            4.15         5th      1948
Bradford           4.25         2nd      1957
Harrisburg         6.05        17th      1888
Johnstown          4.93         3rd      1892
Williamsport       5.24        15th      1895

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 7 AM to 1 PM EST Tuesday for
PAZ004-005-010>012-045-046-049>053-058.
Winter Weather Advisory from 8 AM to 4 PM EST Tuesday for
PAZ006-037-041-042.
Winter Weather Advisory from 4 AM to 1 PM EST Tuesday for
PAZ017>019-025>028-056-057-059-063-065-066.
Winter Weather Advisory until 1 PM EST Tuesday for PAZ024-
033>036-064.

&&

$$

WHAT HAS CHANGED...Evanego
KEY MESSAGES...Evanego
DISCUSSION...Lambert/Dangelo/Evanego
AVIATION...Lambert/Martin
CLIMATE...Dangelo