889
FXUS61 KPBZ 301718
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
118 PM EDT Wed Sep 30 2026

.WHAT HAS CHANGED...
Rain chances for the weekend continue to gradually shift
southward, otherwise no major changes were made to the latest
forecast.

&&

.KEY MESSAGES...
1) Shower chances tonight north of Pittsburgh, then dry and warm
Thursday. Showers return with a Friday cold front.

2) Cooler and mainly dry from this weekend into early next week

&&

.DISCUSSION...
KEY MESSAGE 1...
A ridge of high pressure will maintain dry weather into this
evening. Much of the area should remain dry tonight, though a
weak shortwave is progged to advance eastward tonight, crossing
the Lower Great Lakes region. This wave, and warm advection,
should produce scattered showers for area north of PIT
overnight.

Ridging is expected to strengthen again across the Upper Ohio
Valley region on Thursday, ahead of a trough approaching from
the Midwest. Dry and warm weather is expected, with highs around
10 degrees above average.

The shortwave, and an associated surface cold front, is expected
to approach and cross the region on Friday. The progression of
the front has increased some, resulting in a faster arrival of
cloud cover and showers. This will further limit any possible
destabilization. Shear does increase with faster flow aloft,
though ML CAPE is progged to remain below 250 j/kg. This should
limit not only the severe weather potential, but the overall
chances for thunder. Showers are expected though, with the area
in the right entrance region to an upper jet. Generally expected
1/4 to 1/2 inch of rain with the front, with NBM probabilities
for an inch of rain at 20 percent or less.

KEY MESSAGE 2...
Model ensembles indicate broad upper troughing should persist
across the NE CONUS from the weekend into the middle of next
week. A southern stream shortwave could bring a few showers to
areas south of PIT on Sunday, otherwise mainly dry and
seasonably cool weather is expected through the period as
surface high pressure builds under the broad trough by early
next week.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR conditions are forecast for most of the TAF period as high
pressure ridging is forecast. Mostly scattered cumulus may
continue to provided an occasional MVFR ceiling at DUJ this
afternoon. Southerly wind of 5 to 10 knots persists through
sunset.

Mainly mid and upper clouds are forecast tonight, which should
help to keep fog less widespread as compared to this morning.
Clouds may be thin enough to allow some development near ZZV and
MGW towards sunrise though, and have used TEMPOs for this. In
addition, a weak shortwave riding on top of the ridge may
produce scattered showers north of I-80 overnight. PROB30 groups
were used at FKL and DUJ.

Past sunrise, VFR conditions continue as the ridge intensifies a
bit. Southwest wind around 10 knots is forecast with the onset
of diurnal mixing.

Outlook...
Restrictions in showers are likely with a Friday cold front.
Restrictions are possible south of I-70 Saturday, and across the
remainder of the area Sunday, with crossing disturbances.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.

&&

$$

DISCUSSION...WM
AVIATION...CL