910
FXUS61 KPBZ 311222
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
822 AM EDT Sun Aug 31 2025

.SYNOPSIS...
More seasonable and mostly dry conditions prevail through
Tuesday. Rain chances return Wednesday and Thursday with the
approach and passage of a cold front. The front passage is most
likely Thursday afternoon with gusts of 30mph to 40mph possible.
Cooler and relatively drier weather returns late-week.

&&

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

- More seasonable and dry, save a low chance of rain in Tucker
  County, WV.
---------------------------------------------------------------

With 850mb temperatures slightly warmer than the day prior,
highs are expected in the mid to upper 70s for most (near to
slightly below normal). Once again, some shallow moisture may
allow for an afternoon fair weather cumulus deck.

Models continue to hint on the low chance of a shower or
sprinkle in the West Virginia mountains on the far southern
periphery of the high and ridge-top convergence with perhaps a
hint of a slightly less pronounce capping inversion, though
models are far from optimistic. There a 75% chance the area sees
no rain at all, but in the event of a shower (reliant on deeper
instability) absolute maximum totals would be <1" according to
HREF.

Another radiational cooling night is expected late Sunday under
mostly clear skies and only a light northeast wind. This will
allow another night of temperatures dropping 10 degrees below
normal and valley fog potential.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
KEY MESSAGES:

- Valley fog chances each morning with seasonable temperatures.
----------------------------------------------------------------

Labor Day will be nearly picture perfect. 850mb temperatures
will warm some, allowing daytime highs to sit slightly warmer
than Sunday: in the mid-to-upper 70s for the rural areas and
higher terrain, and close to 80F (seasonable levels) for valleys
and urban areas. A scattered fair weather cumulus cloud deck is
possible with meager low-moisture. Humidity will remain low,
making the air feel comfortable despite the temperature
uptick. Skies remain mostly clear and calm overnight with low
temperatures a tad warmer, but still slightly below normal, with
more Atlantic moisture advection in the low-levels in easterly
850mb flow. Valley fog possible yet again.

A slight return in moisture in southerly flow and a weak
Appalachian trough establishing may see an uptick in clouds
Tuesday, through conditions likely remain stagnant from the day
prior: near average temperatures and dry. While the deterministic
GFS brings rain into the I-68 corridor, its an outlier in
ensemble guidance and would only occur if we receive rather
prolific moisture return from the southeast. Clusters hint this
would rely on the low probability event of a faster eastern
closed low departure. Increased moisture in southerly flow may
keep a few clouds around Tuesday night with a light south wind.
This might locally reduce fog chances and keep temperatures a
couple degrees warmer yet again.

&&

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

- Rain chances return Wednesday and Thursday.
- A cold front likely to drop temperatures late Thursday into
  next weekend accompanied by some gustier winds.
-------------------------------------------------------------------

There is generally high confidence in the pattern for Wednesday
with a northeast closed low departure and an incoming mid-west
trough, placing the region in mostly southwest flow with
increased moisture return in a weak surface trough preceding a
cold front passage. Ensemble mean PWATS jump from ~0.75" late
Tuesday to ~1.15" late Wednesday. This will result in an uptick
in cloud cover yet again with increased precipitation chances.
But most uncertainty Wednesday doesn`t have to do with low
moisture, but rather deep moisture. Most ensemble skew-T plumes
show a nearly saturated profile, with a bi-modal distribution
of some with continued dry air aloft. This will affect
Wednesday rain chance and temperatures. In the deeper moisture,
and slightly more likely scenario, rain total may be 0.2" to
0.5" and highest west of I-77 while high temperatures could be
as low as the low-to-mid 70s. In the drier scenario, the area
may struggle to see any rainfall with temperatures closer to
the 80F mark. An increased pressure gradient with the incoming
trough may also allow some areas to see winds up to 20mph to
30mph occasionally.

Thursday there will high confidence in a longwave trough passage
with a cold front. This will bring a more certain shot of rain
and perhaps a few rumbles of thunder as it passes, with much of
the variability in rainfall totals (>=75%) showing less than 1",
with the highest totals (1.5" to 2" only possible in the event
of the trough cutting off upstream, passing slower, and drawing
in more moisture. Temperature spread maximizes in the 2pm to
5pm hour, indicating the most likely passage of the system
through the area. The combination of the afternoon frontal
passage timing with fairly deep mixing into a ~50kt 500mb jet,
combined with the front speed itself, indicated there may be
some gusts Thursday up to 30mph (40% to 65% chance), or possibly
40mph on the high end (5% to 15% chance).

Friday is likely the coolest day of the forecast period, with
many areas close to or below the 70F mark for highs (10F below
normal). More cool temperatures are forecast for next weekend
with much of the forecast uncertainty tied to the speed of the
trough progression. One cluster with a small subset (10%) of
guidance rushes straight to ridging for the weekend which would
keep temperatures near-normal, but most either show a slower
progression or cut-off that slowly draw away with a gradual
climb of temperatures to near-normal early next week. Though,
regardless, precipitation chances remain low with the only very
low chance of a shower coming from lake-enhancement.

&&

.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
Confidence remains high that a large portion of the TAF period will
experience VFR conditions. Dry and a few fair weather cu expected
with winds light from the northeast.

Overnight, winds will remain light and become more easterly.
Although skies remain relatively clear overnight, the wind doesn`t
become completely calm. This will likely inhibit any river
valley fog development.

.OUTLOOK...
Restrictions are likely to return Wednesday into Friday with the
passage of cold front bringing rain with the possibility of isolated
thunderstorms. With a strong vertical wind profile associated with
the passage of this low pressure disturbance, wind shear and/or wind
gusts are possible as well.

&&

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

&&

$$

SYNOPSIS...Milcarek
NEAR TERM...Milcarek
SHORT TERM...Milcarek
LONG TERM...Milcarek
AVIATION...Hefferan/Lupo