601
FXUS61 KCTP 271859
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
259 PM EDT Mon May 27 2024

.SYNOPSIS...
Severe weather is likely today, mainly over the eastern half of
the state as a low pressure area passes over the Upper Great
Lakes and drags a cold front through by late evening. An upper
level trough will build into the region for the remaining
portion of the week. Occasional showers and a few thunderstorms
are expected Tuesday and Wednesday. The week will end dry and
the dry forecast should last through Sunday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Earlier widespread cloud cover and rather strong low to mid
level shear and the approach of the unfavorable left entrance
region of the Swrly upper level jet has kept any deep convection
in check so far today.

Recovery of the airmass and increasing instability from partial
clearing will support an additional round or two of showers and
TSRA, some of which could become strong to severe, mainly across
the Susq Valley and points east where the highest pwats still
reside and the best low level convergence and directional
shear.

SVR TSTM Watch #333 is in effect for roughly the eastern half of
PA until 01Z Tuesday.

Lowest POPS of just 30-40 PCT will be over the western half of
our CWA. Still a gusty late day/early evening TSRA can`t be
ruled out as a cold front and favorable left exit region of an
upper level jet with enhanced mesoscale UVVEL approaches from
the west.

We should see a few to several deg F rebound in the sfc temps
in most places, which will lead to high temps around 70-72F
across the northern tier counties of the state and mid to upper
70s respectively over Central and Southern PA.

Following the Cfropa early tonight, drier air advects into the
region with SFC dewpoints falling into the 50s late and staying
in the low to mid 50s during the day Tuesday. Clearing within
the well-defined dry slot currently covering much of Ohio and
far Western PA will last the longest over the Central and SE
part of our CWA, while strato cu will move back quickly into the
NW Mtns and shortly afterward across the Laurel Highlands.

The clouds will be too shallow to preclude any showers late
tonight/early Tuesday morning. Low temps will vary from the mid
50s in the north and west and upper 50s to low 60s across the
Central Mtns and Susq Valley.


&&

.SHORT TERM /TUESDAY/...
Upper level energy and 700 mb temps cooling to between -2C and
+2C will help to support increasing vertical depth of the cloud
cover and lead to SCTD-NMRS showers in the afternoon and the
Central and Western Mtns with rainfall amounts ranging from just
a few hundredths of and inch over the Central Mts to between 1-2
tenths over the NW Mtns and Laurels.

Temps may peak only in the low 60s across the highest terrain of
the north and west with 70s in the Central and Southern Valleys.

Westerly winds will frequently gust into the upper teens to low
20s (KTS).

Kept the 30+ PoPs along and north of a line from KAOO-KSEG, but
isold convection is expected in the SE.

The cores of the tallest TCU/CB across the south could get
sufficiently above the -10C level to produce a strike or two of
lightning, but any TSRA (confined to the afternoon hours) will
be isolated and quite low-topped.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
A period of relatively cool weather will stick with us through
Thursday, as a deep upper level trough pivots southeastward from
the Great Lakes. Cold temps aloft should support diurnally
driven showers/storms on Tuesday, with the highest PoPs being
over the elevated heat source of the Allegheny Plateau during
the afternoon hours. There will be a better chc of
showers/storms areawide on Wednesday with the passage of a more
significant shortwave.

PoPs should fall to slight chance on Thursday, as one final
shortwave crosses the region on the back side of the departing
upper trough.

After that, we will trend towards drier and warmer weather
Friday into Saturday, as the upper level trough axis shifts east
of PA and high pressure builds into the region. An approaching
frontal system could bring our next round of showers/storms in
the Sunday/Monday timeframe.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
VFR to occasional high end MVFR will dominate through this
evening with KIPT, KMDT and KLNS possibly dipping very briefly
into the IFR range INVOF any stronger TSRA between 21Z Mon -01Z
Tue.

Cigs will trend higher across the Central and SE Zones tonight
drier air works in from the west with a light breeze continuing
into the overnight hours.

A BKN-OVC MVFR cloud deck will return to the NW Mtns and the
Laurel Highlands during the mid to late night hours as a pool of
much cooler air aloft arrives.

Outlook...

Tue-Wed...Brief restrictions are possible in scattered showers,
but much of the time should be VFR.

Thu-Fri...Predominantly VFR.

&&

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

&&

$$

SYNOPSIS...Lambert/Dangelo
NEAR TERM...Lambert/Dangelo
SHORT TERM...Lambert/Dangelo
LONG TERM...Evanego/Colbert
AVIATION...Lambert/NPB