Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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FXUS61 KPBZ 031809
AFDPBZ
Area Forecast Discussion
National Weather Service Pittsburgh PA
109 PM EST Wed Dec 3 2025
.SYNOPSIS...
High pressure provides dry and chilly weather today. A frontal
passage late tonight and early Thursday provides a light snow
accumulation and a reinforcing shot of cold air. Below-normal
temperatures and additional mainly light snow chances should
continue into early next week.
&&
.NEAR TERM /THROUGH THURSDAY/...
KEY MESSAGES:
- Arctic cold front arriving late tonight with some snow
- Threat of refreezing on roads for the morning commute
---------------------------------------------------------------
The current conditions across the forecast area will feature
the overcast layer to remain over the Upper OH Valley through
much of the day today. While there may be a few peaks of sun
through the end of the day, the cloud cover in advance of an
approaching cold front tonight will allow for cloud cover to
increase in coverage. Onset into the northern counties should
occur by just after 00Z this evening.
The amount of cold air advection behind the front will make for
the coldest air of the year. In fact, there is a potential for
broken records on Friday morning. A lack of moisture, but plenty
of cold air will assure the p-type will be snow. Thus, the
probabilities in the NBM are giving a 30% to 40% prob for an
inch or more over the ridges. The rest of the forecast area is
giving less than 20% for over an inch. With the 75th percentile
giving 1.5 inches in the mountains and the 25th giving a half
inch, there is good confidence that amounts over the ridges will
be less than advisory criteria. The winds are expected to
increase with the front as well adding a blowing snow element at
times.
Heading into the day on Thursday, the front will have passed
through in the morning allowing for the winds to shift to a more
northwest direction. This will add some lake enhancement to the
snow showers. Expect this to continue through the day as
temperatures will slowly fall during the day.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
KEY MESSAGES:
- Near-record low temperatures Thursday morning.
- Low confidence in snow Friday.
----------------------------------------------------------------
Clearing will continue behind the cold front, with high
pressure establishing overnight Thursday. For at least the
early overnight period, the entire area is likely to see very
effective radiative cooling with calm and mostly clear
conditions with a surface snowpack. For the latter half of the
overnight period, there will be some uncertainty to the
efficiency of cooling for regions south of Pittsburgh, with
some Euro ensembles showing clouds approaching, while most
American ensembles stay clear (and cooler). This could be
record breaking cold for many area sites (see climate section).
Much of the temperature variability is in the upper single
digits to low teens, with sheltered valleys likely the coolest
locations.
Cloud cover uncertainty is tied to a larger uncertainty in a low
track for the morning Friday. Some solutions have the low
recurving slightly along the coast, providing some snow chances,
particularly southeast of Pittsburgh, while others have the
zonal flow prevailing, shunting the low offshore to the south.
On the high end, an advisory (3" to 6") might be possible for
the WV high terrain, but on the low end, all areas could see
nothing.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
KEY MESSAGES:
- Below normal temperatures continue early next week.
- More winter weather potential.
-------------------------------------------------------------------
A weak reinforcement of troughing has increased in confidence
Sunday into Monday morning, which may allow low chances of
additional snow showers, though chances are low in any
accumulations >1" (15% to 30%), should they occur at all (40%
to 70% chance). The highest chances of any accumulations would
be for the PA/WV ridges, and the lowest would be in eastern
Ohio.
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 /18Z WEDNESDAY THROUGH MONDAY/...
KEY MESSAGES:
- MVFR or below likely with arriving cold front tonight
- Light snow and restrictions return around 06z tonight
-------------------------------------------------------------------
Expect some lingering MVFR/IFR cigs through the afternoon as the
cloud cover struggles to scatter out. There may be a brief
period of VFR this afternoon but conditions will soon crash
afterward. The cold front is expected dive south tonight with
impacts beginning as soon as 03Z tonight. Expect these low cigs
to impact the region through the TAF period. This along with
intermittent reduction is visibility due to the snow. There is a
potential in terminals such as ZZV and MGW that there may be
some clearing and improvement to VFR by the end of the TAF
period.
Winds are expected to shift to a more westerly direction by
tomorrow morning with an increase in winds. Some winds could
gust to 20 knots at times tomorrow through the day.
Outlook...
VFR is expected to return Thursday night and Friday as high
pressure builds in behind the front. Restrictions are possible
again Saturday and Sunday with a crossing cold front.
&&
.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) 9
Morgantown 11 (1974) 11
DuBois 10 (1991) 6
Wheeling 12 (1944) 10
Zanesville 3 (1957) 9
New Philadelphia 2 (1966) 7
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.
&&
$$
SYNOPSIS...CL
NEAR TERM...Shallenberger
SHORT TERM...Milcarek
LONG TERM...Milcarek
AVIATION...Shallenberger