981
FXUS61 KCTP 030926
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
526 AM EDT Mon Jun 3 2024

.SYNOPSIS...
A warm and moderately humid airmass over the Commonwealth
will be with us through Tuesday with just an isolated afternoon
or evening shower or thunderstorm each day.

An approaching cold front will bring more widespread showers
Wednesday afternoon into early Thursday.

A slow moving upper low will drift southeast from the Great
Lakes, bringing cooler and unsettled weather for late this week
and this weekend with scattered mainly afternoon and evening
showers and thunderstorms.

&&

.NEAR TERM /UNTIL 8 PM TODAY/...
Variable amounts of strato cu and alto cu clouds and rainfree
conditions were found across Central PA early today.

A weak ridge of high pressure at the Sfc and aloft Western and
Central PA should keep rain chances at a relative min (below 15
percent) across that part of the state, while the western edge
of a weak mid level thermal trough dropping south and brushing
our eastern counties could create a few mid to late afternoon
and early evening showers or a brief thunderstorm.

EFS 850mb temps of around in the mid teens C support high temps
this afternoon in the mid mid 70s over the highest elevations
of the Alleghenies, to the low and mid 80s respectively in the
Central and Southern Valleys.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
Skies will become clear to partly cloudy tonight with light
wind as the upper level ridge builds overhead and remains there
through Tuesday. A nearly calm wind may promote patchy valley
fog late tonight, primarily in the favored deep/river stream
valleys of North Central PA.

The upper level ridge and relatively warm temps aloft (with
little llvl forcing from discernible boundaries) is progged to
lie directly over PA Tuesday, suppressing convection in general.

An isolated PM pulse-type shower/tsra is possible though, as
high-level heating promotes favors convection developing over
the SE facing slopes/ridgetops of Central PA.

Ensemble 850mb/2m temp plumes indicate highs may be a degree or
two warmer Tuesday.

The next notable chance for rain arrives on Wednesday afternoon
as a low pressure system drifting across the Great Lakes helps
bring surging Gulf Coast moisture into the northeast. Increasing
clouds on Wednesday will keep temperatures in check with highs
most likely in the mid 70s to low 80s. The chance for showers
and thunderstorms will increase into Wednesday evening.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
The most concentrated showers and possible tsra should come
with the passage of the low level jet just ahead of the
cold/occluded front passage Wed PM into early Thursday. Strong
upper level diffluence and +1-2SD pwats support a decent
rainfall for most of the area. Ensemble plumes suggest most
likely areal average rainfall Wed-into early Thu is around a
half inch.

Latest GEFS and EPS indicate drier weather will arrive by
Thursday PM, as the low level jet/plume of highest pwats shift
east of PA with the exiting cold/occluded front. However,
scattered, diurnally-driven showers appear probable Thu PM
through next weekend, especially over the NW Mtns, associated
with a closed upper low pivoting across the Eastern Grt Lks.
GEFS 2m temp anomalies support highs several degrees below
average Fri-Sun. A decent pressure gradient supports an active
northwest breeze into the nighttime hours, likely holding min
temps near normal for early June.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
Not a lot of change for the 06Z TAF package. Next to no shower
activity occurred on Sunday, hard to see any today or on Tuesday
either.

Main thing will be low CIGS and a bit of fog this morning across
the western mountains. UNV and AOO, and also IPT are less
likely to to have fog, but MVFR CIGS at times will prevail at
these sites. Sites like MDT and LNS are likely to remain VFR.

For late Monday night and early Tuesday morning, lower
conditions will be possible again.

Earlier discussion below.

Rain showers should be east of the central PA airspace by 5-6Z
as forcing wanes. MVFR ceilings will continue for the western
airfields and develop farther east into UNV/AOO/IPT later this
evening through tonight. Fog and IFR Ceilings will be possible
late tonight/early Monday morning for these same spots as
westerly flow results in upslope and stratus development.

Sunrise will bring an improvement to sub-VFR conditions at the
central and eastern terminals. However, the western sites will
take a couple of hours to rise to MVFR then finally VFR. The
instability and left over moisture could spark a SHRA or two
Monday afternoon, but coverage is not expected to be enough to
warrant mention for any site. There is the possibility (15-20%)
for a TSRA at MDT/LNS/IPT in the afternoon, but again have kept
mention out given the low probability at this time.

Outlook...

Tue...AM fog/IFR possible SE. Otherwise, no sig wx.
Wed...Sct SHRA/TSRA with restrictions possible PM.
Wed night-Thurs...CFROPA with numerous SHRA/TSRA. Flight
restrictions likely (70%). IFR possible (30%).
Friday...AM fog poss, sct PM SHRA/TSRA.

&&

.CLIMATE...
Prelim May and Spring 2024 Temperature & Precipitation Rankings

Harrisburg: T12th warmest; 76th driest May
 T3rd warmest; 33rd wettest Spring

Williamsport: 9th warmest; 22nd wettest May
4th warmest; 11th wettest Spring

Altoona: 9th warmest; 13th wettest May
2nd warmest; 3rd wettest Spring

Bradford: 4th warmest; 36th driest May
Warmest; 21st wettest Spring

&&

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

&&

$$

SYNOPSIS...Lambert
NEAR TERM...Lambert/Fitzgerald
SHORT TERM...Lambert/Fitzgerald
LONG TERM...Fitzgerald
AVIATION...Guseman/Dangelo/Martin
CLIMATE...Steinbugl