185
FXUS61 KCTP 311844
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
244 PM EDT Fri Jul 31 2026

.WHAT HAS CHANGED...
* No significant changes

&&

.KEY MESSAGES...
1) Potential for heavy rain and flooding concerns Sunday-Tuesday

&&

.DISCUSSION...

KEY MESSAGE 1: Potential for heavy rain and flooding concerns
Sunday-Tuesday

Strengthening south-southwest flow in advance of a slow moving
upper trough in the Ohio Valley will drive anomalous PW 1.5-2"
into CPA along and ahead of an approaching cold front on Sunday.
Strong warm advection and moisture transport/LLJ combined with
favorable upper dynamics should support active/elevated
convection reaching west-central PA as early as late Saturday
night with max POPs centered on the 24hr Sunday window. Cloud
cover and early day rain showers continue to cast a shadow on
conditional severe wx potential through Sunday afternoon and
evening; however stronger shear values amidst a relatively low
CAPE environment is worth calling out particulalry if there are
breaks of sunshine.

It now appears there will be at least some potential for heavy
rain/flooding through early next week as the upper trough
closes off or trends slower to eject out of the Ohio Valley.
While WPC plans to trim the level 2/4 excessive rain outlook
back a bit over NW PA for Sunday/D3, we will need to watch for
sneaky +RA signal to shift over eastern portions of the CWA
where the level 1 marginal risk will be expanded with the next
ERO issuance later this afternoon.

---------------------------------------------------------------
July = record-setting month in terms of convective warnings.
WFO CTP issued 12 Tornado Warnings in July, which is the most
since 1996 when we issued 25. 95 Severe Thunderstorm Warnings is
the 3rd most in any July on record, behind 1996 (96) and 2021
(122). Year-to- date, 226 Severe Thunderstorm Warnings is the
most on record, passing 2019 (221), and 24 Tornado Warnings is
4th most behind 1998 (55), 2011 (37), and 1996 (30). 250 total
Severe Thunderstorm Warnings + Tornado Warnings is the most on
record year-to-date, passing 2019 (241).

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Scattered convectively driven cumulus clouds blanket most of PA
this afternoon. To start the night, these clouds will give way
to mostly clear skies. A high level (~20kft) cloud deck will
begin to move in from the west overnight.

Prevailing visibility restriction chances look low for
tonight/early tomorrow morning. HREF chances for <5mi visibility
are under 20% at this time across much of the state, but some
signal is present of fog nearby BFD & IPT sites. VCFG was
included in their TAF sites to account for this, but confidence
remains low at this time it will be widespread enough to cause
restrictions.

Winds will be out of the south tomorrow with high level deck
continuing to overspread the area.

Outlook...

Sat...Mainly VFR early with increasing chances of SHRA/TSRA
later in the evening hours. Restrictions possible.

Sun...More widespread SHRA with PM TSRA possible, increased
chances of restrictions in heavier SHRA/TSRA.

Mon...AM SHRA with PM TSRA possible. Restrictions possible,
especially SE where chances for SHRA/TSRA are higher.

Tue...Upper-lvl low over the Ohio Valley may bring SHRA/TSRA
with possible restrictions to the Commonwealth, though lower
confidence in SHRA/TSRA compared to previous days.

Wed...Upper-lvl low moves out, but restrictions still possible
in lingering SHRA/TSRA.

&&

.CLIMATE...
Here are a few key climate callouts to wrap up July 2026:

2nd wettest at Bradford (7.78"/+3.62" above normal)

6th wettest at Altoona (6.18"/+2.70" above normal)

10th wettest at State College (6.09"/+2.30" above normal)

6th most # of days with maxT >=100F at Harrisburg (3)
T3rd most # of days with maxT >=100F at Williamsport (2)

Looking ahead to August, the daylength decreases by 2-2.5
min/day with a total loss of daylight of ~ 70 minutes.

&&

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

&&

$$

WHAT HAS CHANGED...Steinbugl
KEY MESSAGES...Steinbugl
DISCUSSION...Steinbugl
AVIATION...Lambrech
CLIMATE...Steinbugl