677
FXUS61 KPBZ 011154
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
754 AM EDT Sat Nov 1 2025

.SYNOPSIS...
Periodic light showers and seasonable temperatures expected
throughout the week as a series of weak disturbances pass by the
local area.

&&

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

- Chance of lake-effect showers continues north of I-80 through
  this evening before tapering tonight;
- Dry and seasonable elsewhere through today, followed by a
  slight chance for a passing light shower south of I-70 tonight
---------------------------------------------------------------

Much of the area remains under the influence of weak ridging and
surface high pressure through the next 24 hours. This will keep
most of us dry, however WNW winds will continue the 20-30
percent chance for lake-effect showers north of I-80 through
this afternoon/evening.

Tonight, lake-effect activity tapers off north of I-80, but an
upper low over the central Mississippi Valley dives southeast
over the lower Ohio and Tennessee valleys. Depending on how far
south the upper low goes before translating eastward towards the
Southeast Atlantic coast, there is a low chance for a few light
showers to make their way into areas south of Pittsburgh
overnight tonight. The latest HREF suggests the only area where
measurable precipitation may occur is the WV ridges (10-20%
chance), while the NBM remains slightly more "bullish" with
10-20% probabilities across most of eastern OH south of I-70 and
all of northern WV. Regardless, even if measurable precip does
occur, accumulation would be extremely minor (on the order of a
couple hundredths of an inch), with the more likely scenario
tonight being increased cloudiness and therefore potentially
some warmer/milder low temperatures south of Pittsburgh.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
KEY MESSAGES:

- Slight chance for showers south of Pittsburgh on Sunday and
  north of Pittsburgh on Monday as disturbances pass to our
  south and north, respectively.
----------------------------------------------------------------

Sunday and Sunday night, an upper low passing to our south
continues to support low-end chances for some passing light rain
showers south of Pittsburgh. Meanwhile, farther north, dry
weather is expected as low-level winds shift to south or
southwesterly and lake-effect activity ceases.

Monday and Monday night, the low to our south departs the
Southeastern CONUS out over the western Atlantic, bringing any
associated shower activity along with it and returning a dry
forecast to areas south of Pittsburgh. However, at the same time
an upper shortwave trough traversing the northern Great Lakes
and southern Canada will bring rain chances back to the I-80
corridor where low-level winds swing back to west-northwesterly
and lake-effect showers redevelop.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
- Periodic chances of light precipitation as a series of weak
  troughs move across the region
- Generally seasonable temperatures
-------------------------------------------------------------------

A brief period of zonal flow or perhaps weak ridging aloft
keeps the forecast dry Tuesday and Tuesday night, followed by
another passing upper shortwave trough that brings precip
chances back to much of the area late Wednesday into early
Thursday. This disturbance will be far from a washout, with the
latest NBM probabilities for 24-hr measurable rainfall (>0.01")
around 40-50% for much of the area (50-70% northeast of
Pittsburgh). Meanwhile, upping that 24-hr threshold to a meager
tenth of an inch drops probabilities to 20-30% west and south of
Pittsburgh and 30-50% to the northeast.

The active pattern continues thereafter through the remainder of
the long term, with a period of ridging and dry weather briefly
setting up Thursday into Friday, and another trough with precip
chances Friday into the weekend.

Generally speaking, temperatures remain steady and near (or
slightly above) seasonal through the long term period, as none
of the shortwave troughs/ridges passing overhead are high
enough in amplitude to provide much variation.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
As evidenced by morning satellite, there is a bit of high-based
8kft stratocumulus is sliding through the area. This is remnant
moisture trapped below a stark subsidence inversion on the 12Z
sounding at high pressure in the 8kft to 10kft layer.

Modeled moisture is a bit more prevalent in the I-80 corridor,
where daytime mixing may allow for a brief period of MVFR in the
late morning/early afternoon window at FKL and DUJ with 30% to
50% probability. Elsewhere, VFR is very likely with high-based
cumulus.

Some wind gusts are expected throughout the day, but chances of
>25kts are <10%. Winds are expected to subside overnight with
decoupling.

Chances of MVFR cigs increase again after 06Z for FKL and DUJ as
lake moisture and ceilings approach from the north in west-
northwest flow aloft.

.OUTLOOK...
High pressure and ridging will continue to allow high confidence
(>80% chance) of VFR through the period. Low chances of rain
approach from the south Sunday evening and from the north on
Monday.

&&

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

&&

$$

SYNOPSIS...Cermak/Milcarek
NEAR TERM...Cermak/Hefferan/Milcarek
SHORT TERM...Cermak/Shallenberger
LONG TERM...Cermak/Shallenberger
AVIATION...Milcarek