Area Forecast Discussion
Issued by NWS Pittsburgh, PA

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956
FXUS61 KPBZ 271635
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
1235 PM EDT Sun Sep 27 2026

.WHAT HAS CHANGED...
Rain chances east of Pittsburgh this afternoon and evening were
raised slightly. Higher confidence in above-normal temperatures
by Thursday, with increased chances of highs reaching 80. No
other notable changes.

&&

.KEY MESSAGES...
1) Light rain to the east of Pittsburgh on the outer fringes of
the nor`easter
2) A mostly dry stretch of weather from Monday through Thursday with
warming temperatures, before a late week front returns
precipitation

&&

.DISCUSSION...
KEY MESSAGE 1...
The nor`easter spinning just off of the coast of New Jersey is
still expected to spread more cloud cover into the Upper Ohio
Valley during the afternoon and evening hours. Wraparound
precipitation has been making westward progress across PA and is
still expected to reach as far west as Forest, Clarion,
Armstrong, and Westmoreland Counties during the early evening,
with perhaps a few sprinkles further west. Abundant amounts of
dry air below 500mb, as noted on the 12Z PBZ sounding, will
limit rainfall extent and intensity, such that generally 0.10"
or less is expected. A decent pressure gradient and good mixing
should keep northerly 20 to 30 MPH wind gusts going until
sunset stabilizes the boundary layer somewhat.

Rain chances decrease later tonight as the nor`easter starts to
waddle northeastward towards Cape Cod, but a few upslope showers
may linger along the ridges southeast of Pittsburgh as surface
wind backs slightly towards northwest. Clouds should linger
into Monday night.

KEY MESSAGE 2...

As the coastal trough associated with the nor`easter pulls
offshore, 500mb ridging will be able to build across the Upper
Ohio Valley by 12Z Wednesday. Dry weather will result into
Thursday, with that latter day representing the peak of a
warming trend as southwest flow amps up behind a Carolina
surface high. NBM probabilities for 80F or greater high
temperatures that day have risen to between 50 and 80 percent
for most non-ridge locations south of I-80. That said, dewpoints
topping out in the low 60s will keep heat risk concerns
relatively muted. Currently, probabilities for moderate or
higher heat risk levels are 10 percent or less.

There are differences in opinion in the longer-range models
regarding the strength and timing of the next shortwave trough
crossing the Canadian prairies and potentially the Great Lakes
later in the week. Still, at least scattered shower activity
becomes more likely Thursday night/Friday in the moistening warm
sector, with rain chances lingering into the weekend. Severe
weather potential looks muted by meager instability, and
probabilities for significant rain are low (40 percent less or
chance for >0.50 inch in any 24-hour period). Given the
increased clouds and rain chances, temperatures should tumble
back to, or perhaps a bit below, climatology by Saturday.

&&

.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
Light rainfall remains possible across our eastern ports this
evening on western periphery of coastal storm with clouds and
precipitation backing in from east of the mountains. Gradual
moistening of the column will result in VFR ceilings gradually
dropping to MVFR in the evening.

Ceilings will continue to drop becoming IFR at FKL and DUJ
by tonight. Tomorrow morning, IFR ceilings are likely as far
west as KPIT. There is greater than a 60% probability of IFR
ceilings sticking around through Monday morning for most.

Outlook...
Restrictions will gradually improve during the day on Monday.
Due to the chance for radiation fog, there is chance for them
to return Tuesday morning, otherwise conditions will remain VFR
until the next disturbance moves into the area mid to late week.

&&

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

&&

$$

DISCUSSION...CL
AVIATION...Craven/Lupo