288
FXUS61 KCTP 270008
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
808 PM EDT Sun Jul 26 2026

.WHAT HAS CHANGED...
No significant changes.

&&

.KEY MESSAGES...
1) A few gusty thunderstorms possible across portions of the
Lower and Middle Susquehanna Valley this afternoon and evening.

2) Turning more humid and unsettled early in the upcoming week
with the highest probability for showers and thunderstorms
Monday afternoon and evening and again on Tuesday and Tuesday
night.

&&

.DISCUSSION...
KEY MESSAGE 1:  A few gusty thunderstorms possible across
portions of the Lower and Middle Susquehanna Valley this
afternoon and evening.

A weak upper level disturbance embedded in the NW flow aloft
will race SE and over a favorable zone of convergence along a
lee trough that will be situated across the Middle and Lower
Susq Valley this afternoon/early evening.

Surface dewpoints in the low to mid 60s convergence and the
passage of the left exit region of a 90 kt jet max over Ohio and
SW PA late this afternoon will provide the fuel and favorable
larger scale UVVEL for some pulse and small clusters of
strong to potentially svr multicell TSRA across the I-81 and RT
11/15 corridors in southern PA within a fairly narrow corridor
of sfc-based CAPE between 1000-1500 J/KG between 18Z-00Z.
Though dry air aloft and weak shear should help to limit updraft
strength, a few stronger storms may produce isolated strong to
severe wind gusts this afternoon. SPC has maintained the
marginal risk for severe weather across the Susquehanna Valley.


KEY MESSAGE 2: Turning more humid and unsettled early in the
upcoming week with the highest probability for showers and
thunderstorms Monday afternoon and evening and again on Tuesday
and Tuesday night.

There is still some uncertainty regarding the coverage of
storms during the day on Monday as upper level forcing is
expected to remain weak. We should see at least scattered
thunderstorm development during the afternoon as modest
instability develops, but shear will remain weak. The severe
threat appears to be low, but a few strong to severe wind gusts
will be possible with any stronger storms. Some models show an
MCS diving south from the Great Lakes Monday night which could
impact western portions of the area, but confidence is low on
timing and placement of this feature.

Tuesday will likely see the most widespread showers and
thunderstorms of the week as a potent shortwave approaches from
the west and its associated surface low tracks over the region.
Showers and storms will likely be ongoing across parts of
Central PA Tuesday morning and should continue through the rest
of the day. The potential for severe weather remains uncertain
as it will depend on much we are able to destabilize behind the
morning showers and storms. SPC has areas roughly along and
south of I-80 in a marginal risk for severe weather and they
have included far southern portions of the area in a slight
risk.

Heavy rain will also be a concern Monday evening into Tuesday
with any storms that develop as PWAT values will climb to around
1.8 inches. Storms will be very efficient rainfall producers and
areas that see repeated rounds of thunderstorms may see some
flash flooding concerns develop. WPC has placed nearly all of
Central PA in a marginal risk for excessive rainfall for both
Monday and Tuesday.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
Shower/thunderstorm activity will gradually diminish this
evening along the north-south moisture/convergence boundary
near KIPT/KMDT/KLNS, with largely rain-free conditions elsewhere
through tonight. Localized MVFR-IFR restrictions would be
possible underneath these cells, though confidence in these
pulse-y cells being overhead at KIPT/KMDT/KLNS is too low for
TAF inclusion (<30% chance). Otherwise, patchy fog is expected
overnight given light/variable winds and the gradual uptrend in
low-level moisture over the past few days, with highest
confidence in overnight fog currently for KBFD.

Patchy morning fog will give way to primarily VFR conditions
during the daytime on Monday, with scattered showers/storms
ahead of a shortwave over the Great Lakes & Ohio Valley
bringing another chance for localized MVFR-IFR restrictions.
Meager deep-layer wind shear (0-6 km shear around 15 kts) will
support pulse-y cells/clusters, with typical summertime moisture (PWATs
of around 1-1.5") and a well-mixed boundary layer (0-3 km lapse
rates of around 8-9 C/km) driving the chance for visibility
restrictions and localized wind gusts. Chances for TSRA at any
one terminal is around 30% at this time, given the broadly
supportive yet diffuse lifting mechanism at play.

Outlook...

Tue...Restrictions likely with scattered -SHRA/-TSRA.

Wed-Thu...Restrictions possible as -SHRA/-TSRA becomes less
numerous. Patchy overnight fog possible.

Fri...VFR favored with slight chance for -SHRA. Patchy overnight
fog possible.

&&

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

&&

$$

WHAT HAS CHANGED...Bauco
KEY MESSAGES...Lambert/Bauco
DISCUSSION...Lambert/Bauco
AVIATION...Teare