Area Forecast Discussion
Issued by NWS Pittsburgh, PA

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812
FXUS61 KPBZ 252348
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
648 PM EST Tue Nov 25 2025

.SYNOPSIS...
Rain is favored through early Wednesday before a strong front
crosses the region, ushering cooler but drier air through
Wednesday night. Seasonably cool temperature is likely through
the weekend, with potential for accumulating lake effect snow
mainly for areas near and north of interstate 80.

&&

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

- Rain continues into the overnight period but becomes more
  scattered in nature.
- Warm advection plus overcast conditions will maintain a steady
  temperature state
---------------------------------------------------------------

A decaying shortwave trough currently traversing the area will
continue to foster widespread rain amidst modest warm advection
through this evening. Area temperature could see momentary rises
in rain breaks but will otherwise hold steady near the daily
average.

Exiting of the upper level shortwave tonight is expected to end
the widespread, continuous rain occurrence. However, a deepening
trough over the western Great Lakes fostering large scale ascent
within the warm, moist southwest flow around the upper Ohio
River Valley should maintain isolated to scattered rain showers
into Wednesday morning. Due to excessive cloud cover and warm
advection ahead of the next upper trough, temperature will see
little nocturnal fluctuation as they hold steady in the upper
40s to lower 50s.

&&

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

- Rain tapers off morning/early afternoon
- Gusty wind through Thursday
- Falling temperatures Wednesday afternoon, colder Thursday
- Snow showers Wednesday night through Thursday night N of I 70
- Lake enhanced snow along/north of I 80 Thursday and Thursday night

----------------------------------------------------------------

The mentioned upper trough will cross the Great Lakes on
Wednesday with the associated cold front crossing late in the
morning and into the afternoon. Temperatures will fall after
FROPA with strong cold advection behind the front. A tightening
pressure gradient, and steepening lapse rates in cold
advection, will lead to gusty winds after FROPA, continuing into
Thursday. Gusts from 30-40mph are likely for much of the area.
Wind gusts could approach advisory levels (above 45mph) across
the ridges, with NBM showing the highest probability of this
occurrence across the higher terrain of eastern Tucker county
WV. The current forecast uses a 50/50 blend of NBM and NBM90 for
gusts, and eastern Tucker is still the only forecast zone at
advisory levels.

As the upper trough axis crosses the upper Ohio Valley region
Wednesday night, rain will change over to snow with strong cold
advection. Model soundings indicate a lack of saturation in the
dendritic layer which should keep snow rates relatively low.

The focus for snow will be largely north of PGH on
Thanksgiving, as a vort max rotates through the main upper
trough. There could also be some lake enhancement north of I-80
as the boundary layer flow begins to veer from SW to WSW, though
the more favorable area for lake enhancement is just north of
the forecast area. This is supported by latest analogs as well.

As the boundary layer flow veers more to the NW Thursday night,
another shortwave/vort max rotates through the main trough.
Scattered snow showers are expected with this trough across much
of the region, with more numerous lake enhanced snow showers
near and north of I-80. A Winter Weather Advisory looks like it
will be need to be issued for this time period. Will hold off
for now with the hopes that the next suite of hi-res model runs
hone in better on any banding. Current NBM probabilities for
advisory level snow range from 30-75 percent (increasing from
south to north) across the tier of counties north of I-80, and
have continued to include this in the Hazardous Weather
Outlook. Stay tuned for updates./

Much colder temperatures are expected by Wednesday night,
continuing through Thursday night, with readings 10 to 15
degrees below average.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
KEY MESSAGES:

- Snow showers gradually taper off from S-N Friday
- Temperatures moderate over the weekend through early next
  week
- Unsettled weather continues

-------------------------------------------------------------------

With the trough axis east of the forecast area on Friday and
surface high pressure building in from the west, boundary layer
winds will become more southwesterly, and snow should gradually
decrease through the day from S-N, though lingering lake
enhancement could bring additional snow accumulations mainly
north of I-80.

Another shortwave trough is expected to rapidly track from the
Midwest to the Upper Ohio Valley region late Saturday into
Sunday, with rain and snow chances returning. Another trough in
the amplified pattern aloft is expected to approach the region
Monday, with mainly rain chances, though some snow is possible
at the precip onset. Temperatures are expected to gradually
moderate through the period.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Broad ascent with warm and moist southerly flow overnight will
continue to allow the chance of passing rain showers at most
ports, though the predominant conditions will largely be
precipitation free. With nocturnal trends and saturation, cigs
will likely remain low, with LIFR forecast to continue
overnight at FKL/DUJ, and IFR mostly elsewhere. Some slight
downslope drying influence in southerly flow may temporarily
keep MGW/LBE up to VFR/MVFR briefly before 06Z. Chances of IFR
(and VLIFR at FKL/DUJ) drop below 50% in the 10Z to 13Z
timeframe with diurnal trends and mixing and stronger south-
southwesterly winds at daybreak. Given near-saturation and
continued low instability, an occasional shower cannot be ruled
out in the morning, but is generally unlikely until the frontal
passage in the late morning and early afternoon. Southwest winds
will continue to accelerate to 25kts to 35kts with mixing.

This frontal passage will pack the potential for some gusty
showers and perhaps the highest winds of the day with
temperature drops of 15-20 degrees. Along with it, dry and cold
advection will ensue, shifting winds west-southwest all the
while. Tempos mentioned brief 40kt gust potential, matching
about what the NBM max wind projects Wednesday. Whatever cig
restrictions are left come the frontal passage will likely be
replaced by a VFR stratocu deck. Shallow saturation in the
mixed layer and cooling temperatures could also allow a brief
period of light snow showers at the end of the TAF period.

Outlook...
Most terminals maintain VFR by Wednesday night with increasing
subsidence and strong dry advection as upper troughing positions
north of the region, though MVFR cigs could linger near
FKL/DUJ.

Lake effect snow will encroach FKL/DUJ Thursday morning
depending on the angle of the 850mb wind, with a more likely
push of lake bands coming late Thursday night into Friday.
Height rises with surface high pressure should erode any
restriction/snow by Friday night before the next low pressure
system arrives Sunday morning.

&&

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

&&

$$

SYNOPSIS...Frazier
NEAR TERM...Frazier
SHORT TERM...88
LONG TERM...WM/88
AVIATION...Milcarek