Mount Lebanon, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

482
FXUS61 KPBZ 052318
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
618 PM EST Fri Dec 5 2025

.SYNOPSIS...
Periodic light snow chances and below-normal temperatures
continue through the weekend.

&&

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

- Flurries/freezing drizzle possible at higher terrain, however,
  precipitation chances decreasing overnight.
- Overcast skies with low temperatures about 10 degrees warmer
  than Friday morning.
---------------------------------------------------------------

A weak shortwave embedded in the flow will continue to pass to the
south, allowing for some weak column lift, particularly when
combined with a subtle inflection point in the upper jet. This has
allowed some flurries to occur well into the forecast area with the
only chance of any light accumulations in the high terrain (50% to
60% chance of any accumulation). In these areas, there is also the
possibility for some freezing drizzle which will be spotty. The
chance for precipitation will decrease overnight.

Cloud cover is expected to fill-in overnight, making radiative
cooling far less efficient. In addition, the sfc-850mb will be much
warmer than the night prior, keeping forecast lows ~10 degrees
warmer than Friday morning.

&&

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

- Below normal temperatures continue
- Additional waves of light wintry precip over the weekend
- Only minor accumulations expected, primarily north of I-80 and
  in the ridges
----------------------------------------------------------------

A series of weak mid-level shortwaves traverse the Great Lakes
and Ohio Valley over the weekend. The first brings low chances
for light snow showers to areas generally near and north of
Pittsburgh on Saturday, with little or no accumulations
expected. This is further confirmed in the NBM with the
probabilities roughly below 20% for the southern/low elevation
areas receiving even a tenth. The second wave is slightly
stronger than the first and brings higher chances for a wintry
mix to the entire area on Sunday. Precipitation is expected to
start at snow (possibly a rain/snow mix in the Mon Valley)
Sunday morning before transitioning to a rain/snow mix across
the lowlands south of I-80 by late morning and afternoon.
Overall accumulations with the Sunday system are still
anticipated to be light, with measurable snowfall appearing most
likely north of I-80 and in the ridges. The latest NBM
probabilities in those areas suggest a 20-40% chance of
exceeding an inch, 10-20% chance for 2 inches, and a nil chance
for 3 inches. This leaves locations such as Pittsburgh a 40% to
60% chance for just a 20% to 30% chance for even a half inch.

A cold front brings a reinforcing shot of cold air and
northwest flow late in the day Sunday into Sunday night,
will slowly bring an end to the precipitation just about
everywhere by Monday morning. The ridges will likely keep the
flurry activity going through dawn on Monday morning but will
still come to an end rather quickly.

Highs on Saturday and Sunday reach the mid to upper 30s for much
of the area. Lows Saturday night continue a slight warming
trend and remain in the mid to upper 20s, while lows Sunday
night drop back into the teens and low 20s under post-frontal
northwest flow and cold advection. Keep in mind that these
temperatures are still below normal.

&&

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

- Below normal temperatures continue the middle of next week.
- Another round of winter weather potential towards mid week.
-------------------------------------------------------------------

Dry post-frontal flow and building surface high pressure keep
the area dry and cold to start next week. The mentioned high
will keep any precip from lifting north into the forecast area,
as a low pressure system is expected to pass to the south. While
Tucker and Preston counties could see some light snow on Monday,
the amounts will be less than an inch with the rest of the
forecast area remaining dry. In fact the NBM probs give a less
than 10% for even a inch of snowfall.

The Tuesday and into Wednesday disturbance will feature a
strong and progressive low pressure system track in from the
northwest as the trough over the east continues to filter into
the region colder air and precip chances. However, given some
warm advection in from the south on Wednesday, there will likely
be a change over to rainfall. There also stands the chance for
some freezing precip to mix in at times. The Tuesday and
Wednesday shortwave will be one to watch as well as the long
term period features an active pattern. This in conjunction with
the overall colder than normal temperatures expected, can
expect the potential for snow in the extended. Colder air will
filter in behind the front on Thursday.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Staunch MVFR to occasionally IFR stratus covering the southeast
2/3rds of the forecast area appears more and more likely to
remain in place through the overnight period. HREF model data
supports this thought with 70-90% probabilities for MVFR or
lower ceilings to exist at most terminals, with some hint at NW
expansion with weak southerly flow. There remains a non-zero
chance for this region to experience enough lift for localized
light snow or (if ice crystals don`t form) freezing drizzle.
Will preclude TAF mention of that at this time, but it will bear
monitoring. For areas outside of the stratus deck (BVI/FKL),
light wind and radiational cooling may favor IFR/LIFR freezing fog
development that is likely to wane if/when the stratus cloud
deck reaches the terminal.

Increased mixing/lift Saturday morning ahead of an incoming
shortwave should result in some improvements to overnight
restrictions (less likely at FKL/DUJ where warm frontal
convergence occurs). However, any VFR conditions are likely to
be short-lived as the afternoon passage of the shortwave of
surface front re-introduce an MVFR stratocu deck and lower
probability light snow showers (FKL/DUJ having greatest
likelihood for visibility impacts due to snow).

Outlook...
The overall weather pattern through late next week strongly
favors shortwave movement within upper troughing that occurs
almost every other day. Each system will feature varying degrees
of precipitation chances (type mainly snow, save for short
periods of rain at southern terminals), intensities, and either
the continuation of or reintroduction to MVFR-IFR restrictions.

&&

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

&&

$$

SYNOPSIS...Shallenberger
NEAR TERM...Milcarek/Lupo
SHORT TERM...Shallenberger
LONG TERM...Shallenberger
AVIATION...Frazier