702
FXUS61 KPBZ 142355
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
655 PM EST Fri Nov 14 2025

.SYNOPSIS...
High pressure departs tonight with dry weather through most of
tonight. Fast moving low pressure crossing the Great Lakes
tomorrow will bring increasing warmth and moisture along with
the chance of showers and gusty thunderstorms. Brisk and cooler
weather is on tap for Sunday with northwest-flow showers.

&&

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

- Dry for most tonight with above normal low temperatures
- First raindrops may arrive late tonight
---------------------------------------------------------------

The stratocu layer remains thick this evening especially east of
Pittsburgh where mid-level moisture continues streaming through
in northwest flow. Meanwhile, warm advection from the 925-700 mb
layer has driven a scattered deck of lower clouds over the
remainder of the area. Doesn`t look like we`ll be able to
scatter out a whole lot tonight with warm advection continuing
overnight, but the mid-level deck should slide off to the east
with gradual height rises. Overnight lows will hold above
normal and with quite a gradient ranging from near freezing
north of I-80 to values in the mid 40s to the south of I-70.
Enough moisture/isentropic lift may exist after 06Z for the
first drops of light rain to arrive ahead of an approaching warm
front that will cross early Saturday.

&&

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

- Rain chances increase Saturday afternoon and night
- Isolated thunderstorms with gusty wind are possible Saturday
  evening
- Turning blustery and colder Sunday, with showers continuing
----------------------------------------------------------------

The flattening ridge axis crosses the Upper Ohio Valley Saturday
morning, accompanied by the surface warm front. Increasing column
moisture and some modest isentropic lift may continue to fuel some
patchy light rain/showers through the morning. There also could be a
period of several hours that favor an area of advection fog,
particularly north of Pittsburgh, as suggested by HREF visibility
probabilities. This would be in spite of strengthening flow aloft,
although eventually, by midday/early afternoon, wind should become
strong enough, and temperatures warm enough, to lessen the fog
concern.

Attention then turns to the cold front which is slated to cross the
region Saturday evening. A 500mb shortwave will take on a
negative tilt as it crosses the Upper Great Lakes Saturday
afternoon and evening, helping to propel the boundary forward.
CAMs do show shower development along and ahead of the boundary,
but the potential for deep convection still remains
questionable. After weakening a bit in the morning, 0-6km bulk
shear increases into the 45 to 55 knot range during the
afternoon and evening. Instability remains the limiting factor.
A warm layer aloft remains present on model soundings, limiting
CAPE (HREF probs of 200 J/kg generally 50 percent or less from
6PM to midnight), and lapse rates aloft remain poor. Support for
lift to overcome the inhibition remains uncertain. A 250mb jet
will be nosing into the Ohio Valley on Saturday, but timing of
best upper divergence in favored quadrants is not clear. Still,
if evaporative cooling aloft can sharpen lapse rates at least on
a localized basis, some low potential for downward transport of
40-50 knot flow to the surface remains. The SPC day 2 Marginal
severe risk for wind gusts is reasonable. Away from
showers/convection, even modest mixing will allow background
wind gusts into the 20 to 25 knot range. Given the shear and
cold air aloft, some small, graupel-like hail could be possible
in a few cases as well.

Northwest-flow showers should continue behind the front through
Saturday night into Sunday, eventually becoming mainly
concentrated to areas north of US-422 thanks to lake
enhancement. 850mb temperatures falling to subzero values will
allow a mix with, and and eventual change to snow by 00Z Monday,
with any accumulation of note likely holding off until after
sunset. A still-decent surface pressure gradient and better
low- level lapse rates on Sunday should allow for more
efficient mixing, with widespread wind gusts to 30 knots. The
Laurels of course will likely reach higher peaks between 30 and
40 knots. A Wind Advisory may eventually be needed for eastern
Tucker County; NBM probabilities of max gusts greater than 45
MPH are in the 75 to 95 percent range.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
KEY MESSAGES:

- Potential lake effect snow band late Sunday into Monday in
  northwest PA
- Active weather pattern continues, favoring seasonably cool
  temperature
-------------------------------------------------------------------

By Sunday afternoon/evening, cold advection in northwest flow
plus weak vorticity advection will begin to aid development of a
lake effect band over a narrow swath of northwest PA that will
slowly taper off into Monday. The key trends both in global and
initial hi-res model runs suggest slightly cooler 850mb temps
(inching toward -8 degrees C) with subtle wind angle changes
that may create a moisture fetch from Lake Superior through Lake
Erie. If this occurs, a narrow portion of
Venango/Forest/Clarion/Jefferson Counties could see snowfall
accumulations approach/exceed warning criteria (6+) inches.
Confidence remains low without more higher-resolution data as
well as potential variances in the snow band axis, but
highlighted this region for potential snow headlines through the
day Monday.

Otherwise, cold northwest flow with high pressure to the west
will support drying conditions across the region late Sunday
into Monday as area temperature falls back below normal. Residual
pressure gradients and mixing support periods of 25-35mph gusts
through Monday in the lowlands, with potential Advisory level
gusts in the highest terrain of eastern Tucker County. Again, if
confidence increases on this occurrence, wind headlines may be
needed.

The active weather pattern continues Tuesday as lingering
troughing over the eastern CONUS sees a fast-moving embedded
shortwave dip south of the region that will create additional
precipitation chances favoring south of Pittsburgh (current
thermal profiles lends to rain with any snow struggling to
accumulate). Thereafter, long range ensemble models show
increasing variance with placement of upper ridging, suggesting
it either edges east (fostering warming trend and brief dry
period) or remains over central CONUS (maintain cool weather
with intermittent but low accumulation precipitation).

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions are forecast through tonight. Thicker mid-level
clouds will continue to cross with a disturbance aloft as will a
SCT to BKN deck of lower clouds driven by warm advection. Wind
will relax overnight and hold with a very light flow out of the
southwest. For ZZV, surface flow is expected to be light enough
with a lingering low level jet to result in a period of low
level wind shear from roughly 04z-10z at which time the jet will
depart. MGW may be close to wind shear criteria but was not
confident enough to include in the current TAF.

Clouds will thicken and lower tonight with an approaching warm
front. A few non-restrictive light rain showers may begin to
arrive after 06Z and spread north through the morning. With a
crossing warm front bringing a low-level moisture push, model
soundings are suggesting the development of advection fog
beginning around sunrise and overspreading some areas near and
to the north of PIT. Probabilities of MVFR ceilings begin to
spike above 80 percent after 10Z or so, mainly south of I-70,
before overspreading other terminals during the rest of the
morning. IFR visibility probabilities are highest (above 50
percent) in the I-80 corridor from mid-morning into early
afternoon. Thus, at FKL/DUJ, prevailing IFR ceilings were
introduced with fog/mist and light showers. The southern extent
of these restrictions remains a bit uncertain, and PROB30s were
maintained for potential impacts at all other terminals.
Southwest wind will begin to pick up after sunrise, with gusts
to 20 knots possible. A drier period will return for a few hours
in the early afternoon in the open warm sector ahead of an
approaching cold front that will pass late Saturday evening.

Outlook...
Restrictions should become more widespread as Saturday
progresses with better chance for showers and elevated wind
gusts Saturday evening along a cold front. Wind will shift to
the northwest and gust to 20-25 knots late Saturday. Lake-
enhanced precipitation is expected behind the front on Sunday
with the typical scattered nature.

&&

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

&&

$$

SYNOPSIS...Frazier/MLB/CL
NEAR TERM...MLB/CL
SHORT TERM...CL
LONG TERM...Frazier
AVIATION...MLB/CL