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162
FXUS61 KCTP 231406
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1006 AM EDT Thu May 23 2024

.SYNOPSIS...
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A cold front over Northwestern PA will push southeast through
the region by early this afternoon. 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.
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&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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Deep convection associated with 0-6km 40kt maximum in bulk shear
which propogated across south central PA has pushed east of the
Commonwealth at mid morning. Deep layer moisture is decreasing
nicely over NW PA with sfc dewpoints dropping through the 50s
over the NW Mountains, and clearing pushing into the Central
Mountains. Diffuse and stalling cold front is settling through
the Central Mountains and the deeper layer moisture across the
southern half of PA in the vicinity of this boundary can still
touch off an isolated shower or thunderstorm at the diurnal
heating max this afternoon.

Adjusted sky grids for earlier clearing over the central
mountains and subsidence behind the early morning convective
complex for some bonus sunshine. This could add a few degrees to
afternoon highs, and still expecting a range from the mid 70s
north to the lower 80s.
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&&

.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 /14Z 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/DeVoir
NEAR TERM...DeVoir/De Koning
SHORT TERM...Lambert
LONG TERM...Lambert/Fitzgerald
AVIATION...NPB
CLIMATE...Steinbugl