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139
FXUS61 KCTP 080139
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
939 PM EDT Mon Jul 7 2025

.SYNOPSIS...
* Hot and humid today with thunderstorm downpours concentrated
  in the northwest Alleghenies and near the I-95 corridor
* Thunderstorms will be focused primarily over the southeastern
  half of the Commonwealth Tuesday afternoon
* Seasonably warm and muggy for the rest of the week with
  scattered thunderstorms during the afternoon and evening

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Partly cloudy skies are over all of Central PA this afternoon
with the remnants of Chantal now pushing east of the area and
more widespread showers and storms along a cold front not quite
into our area yet. Hot and humid conditions continue today with
max temps in the mid 80s to low 90s or 5-10F above the
historical average for early July. Max HX values will approach
100 in many of the central and eastern valleys.

The main hazard of concern today will be scattered showers and
thunderstorms along/ahead of a slow- moving cold front pushing
southeastward from the Lower Great Lakes. Around 25-30kt of
effective shear in northwest PA amid a diurnally destabilizing
boundary layer will allow for loosely organized multicell
clusters capable of producing isolated wind damage (svr tstm
risk level 1 out of 5 or MRGL). HREF 3hr QPF PMM signal also
highlights a locally heavy rain threat across this area (peaking
18-21Z downwind of Lake Erie) with >1.5" pwats supporting some
isolated point amounts of 2+ inches possible. A Slight Risk of
excessive rainfall is in place for much of northwest PA where
scattered instances of flooding are possible.

Farther southeast, modest instability will continue to sustain
some stronger updrafts despite waning shear profiles. Gusty
winds and heavy rain are possible with any storms that fire,
though it will likely take multiple rounds of storms to produce
flooding and wind gusts should be isolated/short-lived.

Coverage of showers fades overnight with a good signal for post
frontal low clouds over the western mtns and areas of fog across
the central and eastern valleys. Another warm and muggy night in
most locations with low temps in the 65-75F range.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Max temps drop 5-10 degrees behind the front over the western
1/2 of the CWA on Tuesday. The latest guidance shows the front
stalling out or becoming quasi stationary over CPA by 00Z Wed.
Latest D2 outlooks from SPC and WPC include an upgrade to slight
risk for severe storms(level 2 out of 5) and excessive rainfall
(2 out of 4) mainly for areas to the southeast of the frontal
zone where there will be plenty of MLCAPE and 70+ dewpoints.
Tall or thin profiles suggest heavy rain potential along with
water-loading/severe downdraft potential. Latest CAMs depict
scattered thunderstorms congealing into a line of storms Tuesday
afternoon with an attendant increased risk for damaging straight
line winds.

Ahead of the rain, there also remains some concern for max HX
values to reach or exceed the century mark in the LSV Tuesday
afternoon. A heat advy may be needed; for now we coordinated
with PHI to not include any of the Lehigh/Lower Susq zones but
will continue to highlight in the HWO.

Best odds for a thunderstorm on Wednesday remains along the MD
line where the best moisture/instability overlay will exist. At
this time, t-storms are expected to be non-severe with heavy
rain risk shifting to the south of the Mason Dixon line. Max/min
temps remain seasonably warm for early/mid July.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
PoPs rise again Thursday with the approach of another shortwave
trough. The forecast for Friday and the weekend is more
uncertain, with some guidance suggesting a break in the
unsettled pattern, and others suggesting active weather
continues. An active pattern would favor continue heat/humidity
while a quieter pattern could support the intrusion of lower
dewpoints and more refreshing conditions.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
Isolated showers and storms are diminishing, but will continue
to briefly affect many TAF through about 04Z/8th ahead of a
slow moving cold front.

Patchy fog is possible at all TAF sites late tonight and
Tuesday morning. However, cloud cover and a light breeze from
the west later tonight will likely negate a significant threat
for widespread fog. IFR/LIFR ceilings are favored for several
hours at BFD and JST with MVFR likely at IPT, UNV, and AOO.

A few showers could develop by midday on Tuesday, but showers
and thunderstorms will become more widespread into the
afternoon. Brief restrictions are possible everywhere except
BFD, with storms starting in the vicinity of a line extending
from JST/AOO to UNV to IPT and then moving east-southeastward
and affecting MDT and LNS later in the afternoon/early evening.


Outlook...

Tue PM...Showers fade, fog possible across much of the region
into Wednesday morning.

Wed...Best chance for storms and restrictions in southern PA.

Thu-Sat...Potential for showers and thunderstorms, mainly
aftn/eve.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...Steinbugl/Banghoff
NEAR TERM...Steinbugl/Banghoff
SHORT TERM...Steinbugl/Banghoff
LONG TERM...Lambert/Banghoff
AVIATION...Banghoff/Gartner