Area Forecast Discussion
Issued by NWS Pittsburgh, PA

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639
FXUS61 KPBZ 042054
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
354 PM EST Thu Dec 4 2025

.SYNOPSIS...
High pressure will promote clearing skies and light wind which,
combined with existing snow cover, will result in overnight
lows dipping into the single digits to mid-teens. Additional
light snow chances and below- normal temperatures should
continue into early next week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
KEY MESSAGES:

- Erosion of area clouds continue as cold air mass settles into
  the region
- Near-record low temperatures Friday morning
---------------------------------------------------------------

As flow aloft lightens and becomes more zonal, surface high
pressure will slide over the upper Ohio River Valley through
tonight. This will continue to erode area stratocu and any
lingering flurries in the post- frontal environment while
allowing the colder air mass to settle into the region.

The combination of the cold air mass, clearing skies, residual
snowpack and light wind creates high confidence in it being the
coldest night of the season as temperature falls into the
single digits (north of Pittsburgh) to teens. This puts daily
low records at risk of being broken for most of the region`s
climate sites (see Climate Section for specific values at play).
However, there remains a decent spread in potential low
temperatures that creates uncertainty in those records falling,
in small part due to some locations see enough wind mixing to
limit cooling. More likely, for areas near/south of I-70, the
variability in the outcomes is being driven by the potential for
increasing mid to high level clouds south of Pittsburgh from
the southern approach of a weak shortwave and surface low. And
for areas to the north, that variability is similar (i.e. extent
of cloud coverage) but tethered to some uncertainty in the
erosion of Lake Erie influenced stratocu.


&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
KEY MESSAGES:

- Near-record low temperatures Friday morning.
- Low confidence in snow Friday.
----------------------------------------------------------------

Generalized zonal flow over the Ohio Valley on Friday will be
marred slightly by a flat mid-level wave, with a surface
reflection tracking across the Deep South. The most likely
scenario remains a round of light snow for the WV ridges of
under an inch. The total range of scenarios run from a far
south storm track with no snow at all in the forecast area, to
a partial re-curve along the Atlantic Coast that could push
light snow as far north as Pittsburgh, and provide a few inches
to the ridges of Preston/Tucker Counties. Given the pattern, the
former seems like a more reasonable outcome than the latter.
Any snow would depart by sunset, leaving a dry and cold Friday
night.

&&

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

- Below normal temperatures continue into early next week.
- More winter weather potential.
-------------------------------------------------------------------

The troughing pattern continues through the extended period,
continuing the trend of below-normal temperatures. Periodic
shortwaves within the longwave pattern will provide several
chances for snow through the period. At this time there is not a
signal for any large event, but in any case, there is generally
a 20 to 50 percent chance according to the NBM of a total snow
accumulation of one inch or more through the period. The highest
chances of any accumulations would be for the PA/WV ridges, and
the lowest would be in eastern Ohio. A reinforcement of cold
temperatures appears likely; maximum values in the 30s
Saturday/Sunday have a 70 percent chance or greater of falling
below freezing on Monday.

Mid-to-late week temperature uncertainties would be more tied
to amplitude uncertainty of the semi-persistant eastern trough.
A stronger prevailing trough would allow for cooler conditions,
with higher chances of low-QPF snowfall. A weaker trough would
likely correlate to warmer conditions with higher QPF potential
in mixed precipitation events.

&&

.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
KEY MESSAGES:

- Snow is ending
- Clearing is expected tonight with much colder temperatures
-------------------------------------------------------------------

The cold front that dived south across Lake Erie and across the
forecast area will continue to drop southeast. Expect some MVFR
and even IFR cigs to continue through the afternoon before
seeing some clearing tonight. By 22Z across the area, most
locations should clear out and become VFR. The lone exception
would be FKL and DUJ in the north as the MVFR conditions hold on
for a bit longer as the HREF probs still give a 60% prob of
cigs at 3 kFT or lower.

Winds will gust out of the northwest through this evening with
some gusts reaching 20 knots at times. Winds will then become
calm overnight with some light and variable winds expected
tomorrow.

Outlook... Restrictions are possible again Saturday and Sunday
with a crossing cold front. This will create another snow shower
event where MVFR and IFR restrictions are possible.

&&

.CLIMATE...
At least four of our climate sites have a chance to challenge
record low temperatures for December 5 on Friday morning. Two
other sites are less likely to approach their record lows.

                 Current 12/5          Forecast
Site             Record Low               low
----             ----------           ------------
Pitt Intl        12 (1976)            11
Morgantown       11 (1974)            14
DuBois           10 (1991)            7
Wheeling         12 (1944)            12
Zanesville       3 (1957)             11
New Philadelphia 2 (1966)             9

&&

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

&&

$$

SYNOPSIS...CL/88
NEAR TERM...Frazier
SHORT TERM...CL/88
LONG TERM...CL/88
AVIATION...Shallenberger