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000
FXUS61 KCTP 251912
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
312 PM EDT Mon Sep 25 2023

.SYNOPSIS...
The easterly wind off the ocean will keep moisture flowing into
the state into Tuesday, resulting in lots of clouds and patches
of rain. High pressure nosing down from eastern Canada will
provide a brief dry period during mid-week. An upper level
trough will then move across the area later in the week.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Low clouds and areas of drizzle persisting across central PA
this afternoon as deep easterly flow around eastern Canadian
anticyclone with deep fetch over the Atlantic reinforces the
llvl moisture. Simultaneously high level moisture increasing
from the west as shortwave trough approaches from Ohio. Upper
trough slides PA tonight, with its forcing acting on lingering
moisture to produce another round of light rain showers and
drizzle to especially the central and western parts of PA.
QPF will be on the light side, and POPs are well collaborated
with our western neighbors for tonight into Tuesday morning..
Temps tonight will dip into the upper 40s NE to mid 50s Lower
Susq.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
The showers will last into the morning, with the focus shifting
slightly to the south into the srn counties. Drying tries to
occur throughout the day. The big sfc high over Que and New
England will build and raise the pressure along the spine of the
Appalachian Mtns. This action, and the slow exit of Ophelia
should dry it up for the afternoon. Not much hope for sun to
break through in the SW half of the area. But, the NE should
have clouds start to break toward sunset. Will hold SCT/CHC PoPs
in the SW thru the entire day. Will continue to hold maxes like
we had them Sun and Mon without much hope for sun/mixing and
slight cold advection in the lower atmos.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Latest guidance supports a gradual trend toward drier/brighter
weather on Wednesday as expansive high pressure over Quebec
nudges south. A lingering, upsloping easterly flow could cause
low clouds/showers to persist over the Laurel Highlands, while
the greatest confidence in brighter skies is across Northeast
PA.

By late week the focus shifts to an upstream trough over the Grt
Lks. Latest GEFS and ECENS track this feature across PA Friday,
with a weak accompanying surface low passing south of the state.
A fairly tight gradient between the weak surface low and a
strong high north of New England should result in a fairly
decent easterly flow/plume of the Atlantic moisture into the Mid
Atlantic Region. This, combined with large scale forcing ahead
of the trough, may result in a period of rain Thursday into
Friday, especially where orographic forcing is best over the
Laurel Highlands.

Upper level troughing and a persistent easterly flow off of the
Atlantic should result in below normal temperatures through
much of the upcoming week. However, a return to brighter,
warmer and drier weather appears likely next weekend, as the
upper trough exits the coast and ridging builds in from the Grt
Lks. Temperatures will trend +5 to +10 degrees compared to
normal for beginning of next week with above normal
temperatures and below normal precipitation expected into the
first week of October.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
The persistent stretch of restrictions will continue for the
next few days. All sites should improve to MVFR this afternoon
for at least a few hours before an increase in shower activity
arrives later this evening. All sites except IPT will dip to IFR
overnight as ceilings lower and visibility reductions become
more widespread.

Conditions will gradually improve from northeast to southwest
during the day on Tuesday, with scattered showers continuing
into the afternoon across the Laurel Highlands and south central
mountains.

Outlook...

Tue...Lingering -RA early, more scattered -SHRA PM.

Wed-Thu...Morning fog, otherwise VFR with a few -SHRA across
the west.

Fri...Sct -SHRA areawide early, clearing to the west late.

&&

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

&&

$$

SYNOPSIS...DeVoir/Dangelo
NEAR TERM...DeVoir/Dangelo
SHORT TERM...DeVoir/Dangelo
LONG TERM...Fitzgerald/Banghoff
AVIATION...Colbert/Banghoff