023
FXUS61 KPBZ 280135
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
935 PM EDT Wed Aug 27 2025

.SYNOPSIS...
Mostly dry weather expected Wednesday. A crossing cold front
returns rain chances late Thursday into early Friday. Dry
weather returns for the weekend with gradually warming, but
still below normal, high temperatures

&&

.NEAR TERM /THROUGH THURSDAY/...
KEY MESSAGES:

- Mostly dry today
- Temperature near 10 degrees below normal
---------------------------------------------------------------

Evening Update...The forecast is on track for the most part with
mid and high level cloud cover moving into the region. Some
instances of fog will be possible. There will also be the
potential for low temperatures at Canaan Valley to drop into the
mid 30s again and possibly lower. Have mentioned this in the AFD
and some social media posts but the impact is not widespread
enough for a headline and really in a microclimate. Some
instances of isolated frost will be possible.

Previous discussion...Lake effect precipitation through today
will be lesser than the previous two days with detrimental
effects from a sinking subsidence inversion under building high
pressure and drier low- levels. A shower or two is possible
primarily north of Pittsburgh, but most should remain dry today.
Diurnal cumulus will blanket the area through sunset with
achievement of convective temperatures and a thin layer of
moisture to work with around 700 mb on our morning sounding.

Flat mid-level ridging will also build in the wake of a departing
trough and allow for slight recovery in temperatures compared to
yesterday. That said, still persistent surface northwest flow will
hold highs 8-10 degrees below climatological norms.

Upper 40s for most are favored for lows tonight with typical warmer
urban areas in the low 50s, though with increasing cloud cover as a
shortwave passes overnight we likely won`t bottom out as much as
last night. Canaan Valley dipped down to 28F Tuesday night with
surrounding terrain obs in the 30s/low 40s, so expect another
similar trend down that way tonight.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
KEY MESSAGES:

- Rain returns late Thursday
- Coolest day of the week on Friday
----------------------------------------------------------------

Brief mid-level ridging will come to an end on Thursday as yet
another unseasonably deep low establishes over Quebec. Surface high
pressure will simultaneously migrate toward Delmarva and offshore.
The upper low will throw a shortwave around the base of the trough
as a cold front moves through locally in the late afternoon
and evening hours.

Moisture return ahead of the boundary will be weak despite a period
of southwest flow with 40s dew points extending all the way down
into KY/TN; ensemble mean PWAT values reach to right around an inch
locally. Both the NBM and HREF suggest that measurable precip probs
extend about as far south as the Mason Dixon line and highest north
of US-422 (60-70%). The chance for >0.25" is only about 20-30% to
the north, so outside of very low probability convective enhancement
(MUCAPE unlikely to exceed 500 J/kg), this will be a light rain for
most.

A few showers may linger in the ridges and along the I-80
corridor Friday morning with upslope and lake enhancement, but
dew points will come crashing back down in the wake of
Thursday`s cold front and shut off precip quickly for the
lowlands. Low level cold advection in northwest flow will drop
850 mb temperatures to 6-8C, and a shallow layer of moisture
will likely reinforce stratocu coverage, so highs will struggle
to reach out of the 60s north of Pittsburgh and in the higher
elevations. Low 70s are expected elsewhere with a gusty wind at
times.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
KEY MESSAGES:

- Quiet weekend with rebounding temperatures
- Remaining dry into the beginning of next week
-------------------------------------------------------------------

The upper trough departs headed into the weekend allowing for
heights to gradually rise beginning on Saturday. One ensemble
cluster, dominated largely by the GEPS, suggests a slightly slower
trough departure and lower heights locally which would point
toward temps being slightly cooler than currently forecast, but
this solution is low probability. More likely is that low 70s
return for most on Saturday with mid to upper 70s on Sunday, dry
weather under high pressure, and a quite pleasant weekend to
close out August.

That theme continues into the beginning of next workweek with highs
inching back closer to climatological normals, though a drastic
warmup appears unlikely with ensembles converging on a troughing
solution locally as ridging builds across the western half of the
country. Surface high pressure looks to remain in control with a 20%
or less chance of rain through the beginning of the week.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
High pressure in place over the region will make for a night of
dry weather. A few instances of fog will be possible towards
dawn but otherwise, VFR conditions will prevail. Light winds are
expected through dawn and into late morning.

A cold front is expected to dive southeast into the region
through Thursday afternoon and evening. This will bring some
showers and thunderstorms to impact the northern terminals.
Thus, some MVFR and evening IFR is possible at locations such as
FKL, DUJ, and BVI. Some PROB30s were used to cover this. Winds
have the potential to gust up to 20 knots during the afternoon
and evening.

.OUTLOOK...
Approaching upper trough may lead to area showers and
restrictions favoring northwest PA Thursday evening into Friday
morning. This will give way to VFR and dry weather over the
Labor Day weekend.

&&

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

&&

$$

SYNOPSIS...MLB
NEAR TERM...MLB/Shallenberger
SHORT TERM...MLB
LONG TERM...MLB
AVIATION...Shallenberger