603
FXUS61 KCTP 231132
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
732 AM EDT Thu May 23 2024

.SYNOPSIS...
A cold front over Northwestern PA will push southeast through
the region by early this afternoon preceded by an area of
showers and thunderstorms.

A ridge of high pressure will slide east across the state
Friday brining a nice day with dry conditions and comfortably
low humidity.

More clouds and an uptick in humidity will arrive for the
upcoming weekend and persist through Memorial day with a period
or two of showers and possible thunderstorms, mainly on Saturday
and Monday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A period of enhanced meso-B lift will accompany the nose/left
exit region of a rather potent, 90 kt upper level jet headed our
way from the middle ohio valley.

An expanding cluster of fast, NEWD moving showers and
thunderstorms were impacting the Western (and soon the Central
Mtns and Susq West Branch Valley) over the next 1-3 hours.

Stronger convective cells are capable of localized strong wind
gusts as their water and small hail-loaded cores collapse
through the 35 to 40 kts 850-700 mb speed max.

The cold front will drift south to near the Mason/Dixon line by
the mid afternoon hours and stretch out more in an east/west
direction. This will limit any chance for showers or a
thunderstorm to primarily the southern tier counties of PA
after 18Z today.

SFC dewpoints behind the cold front will fall quickly through
the 50s and into the 40s several hours behind the front later
this morning and this afternoon with sunshine being filtered by
high clouds.

The high level cloudiness extending into Northern PA should
hold temps down with expected highs ranging from the mid 70s to
low 80s, which are still slightly above climo for this time of
year.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
Rain chances trend lower from north to south tonight into
Friday as surface and upper level ridging builds over the area.
Max POPs 25-35% are over the southern tier of central PA near a
stalled/pivoting quasistationary front and axis of highest
PWATs. Friday looks like a pleasant day across most of the
region with temperatures in the upper 70s to mid 80s and a good
amount of sunshine.

The front lifts back to the north as a warm front Friday night
with showers likely by Saturday morning over the western
Alleghenies. More widespread showers and storms will develop
Saturday afternoon with daytime heating and some enhancement
with a prefrontal trough. Saturday will not be a washout by any
means, but those with outdoor plans should monitor the weather
and head inside if you hear thunder.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Compared to Saturday, the chance for showers and thunderstorms
on Sunday will be lower, owing to a weak surface high building
across the Lower Grt Lks into PA. However, with a warm front
approaching, we do carry slight chance to chance PoPs Sun
afternoon, with PoPs increasing to likely Sunday night as the
warm front crosses through the region.

A deepening upper trough will then likely result in a period of
unsettled weather continuing into Memorial Day and the first
half of the upcoming week with mainly scattered, diurnally-
driven convection expected.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
Thunderstorms across the eastern airspace will continue moving
eastward early this morning with MVFR vsbys/cigs with locally
lower reductions. Rain is expected to continue for the next
couple of hours with MVFR cigs/vsbys expected. Improvement is
expected by late morning with the majority of the area trending
towards VFR conds by 16-18Z Thursday. Some clear skies remain
possible across N PA later this afternoon.

Guidance has started to indicate some chance of low vsbys and
cigs overnight Thursday into Friday morning, with recent GLAMP
guidance and RAP guidance suggesting JST to experience an
extended period of IFR/LIFR conditions. Given some uncertainty
with regards to extent, have kept restrictions limited to JST at
this time after 08Z Friday.

Outlook...

Fri-Mon...Mainly VFR, but chance of showers/AM patchy fog.

&&

.CLIMATE...
Daily record maximum temperatures for 5/22:

Harrisburg96/1941
Williamsport95/1941
Altoona88/2013
Bradford84/2013
State College89/1975

&&

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

&&

$$

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