816
FXUS61 KCTP 061111
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
711 AM EDT Mon May 6 2024

.SYNOPSIS...
A slow moving cold front will bring scattered showers and
possibly a few thunderstorms across south central PA this
afternoon. The front will come back north as a warm front late
Tuesday through Tuesday night, bringing more widespread showers
and storms. The most widespread rainfall will occur Wed night
into Thursday, followed by scattered showers lingering for
Friday and the weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Widespread fog has developed across central PA overnight, with
a handful of obs reporting quarter mile vsby. A dense fog
advisory remains in effect through 10 AM for the lower Susq
Valley north through Schuylkill County, where PennDOT RWIS obs
have recorded vsby under 1000 ft on portions of Interstate 81.
Daytime heating will mix out the low level moisture and lead to
dissipation of the fog by mid morning in most areas.

A weak cold front pushing eastward through the area has a few
showers along it early this morning. As it moves south of
Interstate 80 this afternoon, it will tap into enough moisture
and instability to support more numerous showers and perhaps a
few thunderstorms as the front approaches the Maryland border.
The highest chance for a few lightning strikes will be across
the Laurel highlands, where MLCAPE is progged to reach 750-1000
J/kg. Meanwhile, enough dry air will nudge into northern PA for
a few peeks of sunshine.

Temperatures will rise into the mid 70s for much of central PA
this afternoon, which will feel noticeably warmer than this
past weekend.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
Most model guidance shows the convective activity along the
southern tier waning tonight with the loss of daytime heating,
but isolated to scattered light rain showers will likely
persist. Some fog is possible tonight as well, though
confidence in fog is not as high as it was last night. Low temps
will range form the mid 40s along the NY border to around 60F
in the southern tier, with the north to south gradient in
moisture playing a large role in overnight cooling.

Upper level ridging over PA indicates warmer conditions are
likely Tuesday with highs reaching the upper 70s to near 80F.
A warm front lifting out of the Ohio Valley and a 500mb short
wave trough will result in increasing clouds with a PM
shower/tsra, primarily across the western counties. Showers and
a few storms will overspread the area Tuesday night.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Unsettled weather will continue into the extended period.
Wednesday looks to be another warm day, with ensemble mean
850mb temps of 16C suggesting max temps well into the 80s
across the Lower Susq Valley.

The best chance for widespread showers and thunderstorms
continues to be focused on Wed night into Thursday, with a
deepening upstream trough and sfc low pressure riding up the
Ohio Valley and across the area. The SPC highlights our area in
a MRGL risk for severe weather during this time frame, on the
periphery of a SLGHT-ENH risk area over the Ohio Valley.

The surface low and deepest moisture is progged to shift east
of the area Thursday night. However, falling heights ahead of
the upper trough will likely support scattered diurnal
convection Friday through Sunday, along with a downward trend
in temperatures.

&&

.AVIATION /11Z MONDAY THROUGH FRIDAY/...
A moist southeast flow off of the Atlantic Ocean will maintain
stratus over Central PA tonight with widespread IFR/LIFR cigs
and ridgetop fog. Improving flying conditions look likely
Monday as high pressure builds into the region from the Grt Lks,
causing winds to shift from southeast to north. Latest forecast
soundings and ensemble prob charts support a transition to MVFR
during early afternoon and potentially VFR by late in the day.
Low pressure lifting up the Ohio Valley could spread showers
and reduced cigs into the southern tier of PA Monday evening.

Outlook...

Tue...AM low cigs/showers possible southern tier of PA. Isold
evening tsra impacts possible W Mtns.

Wed...AM low cigs/tsra possible.

Thu...Rain/low cigs likely.

Fri...Showers/low cigs possible, mainly AM.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 10 AM EDT this morning for PAZ057>059-
065-066.

&&

$$

SYNOPSIS...Colbert
NEAR TERM...Colbert
SHORT TERM...DeVoir/Colbert
LONG TERM...Fitzgerald/Evanego/Colbert
AVIATION...Fitzgerald/RXR