Rural Valley Pennsylvania Weather Forecast Discussion

364
FXUS61 KPBZ 101634
AFDPBZ
Area Forecast Discussion
National Weather Service Pittsburgh PA
1234 PM EDT Fri Oct 10 2025
.SYNOPSIS...
High pressure over New England continues dry and cool conditions
through Saturday. Rain chances rise Saturday night and remain
through the early week especially across the eastern ridges as a
weakening Great Lakes low combines with a developing coastal
storm.
&&
.NEAR TERM /THROUGH TONIGHT/...
KEY MESSAGES:
- Clear, cool and quiet.
- Warmer overnight temperatures than previous nights.
---------------------------------------------------------------
High pressure weakens some and is shunted east through the day as
the upper ridge axis moves off the Eastern Seaboard. Despite this
weakening, today is expected to remain dry with clear skies. Winds
will be light and largely southerly across the region owing to the
retreating high pressure. High temperatures are expected to be near
normal and peak across the region in the mid to upper 60s.
Southerly winds are expected to persist overnight and hamper
efficient radiative cooling, kicking the low temperatures back up
into the low 40s ending our frost/freeze concerns. Cloud cover is
also expected to increase overnight ahead of an approaching trough
moving in from the northwest.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
KEY MESSAGES:
- Slight warming trend and dry conditions through Saturday.
- Rainfall through Monday favors northern and eastern areas.
----------------------------------------------------------------
Our pattern begins to shift as we move through the day Saturday. At
the upper levels the closed upper low from the Great Lakes slides
over central PA and begins to open up as it interacts with the
closed upper low over the Southeast. At the SFC, a Great Lakes low
and its associated cold front begin to drown out and transfer energy
to a budding coastal low climbing the Eastern Seaboard. The coastal
low slowly moves north and east hindered by stubborn high pressure
Sun-Mon.
These interactions look to work in tandem to lower rain chances
across our region as the highest POPs and rainfall totals shift
eastwards over the mountains nearer the developing coastal low. Rain
chances peak across our northern tier counties late Saturday as the
Great Lakes low weakens (near 30%) and then across our eastern ridge
counties Sunday and Sunday night as energy transfers to the coastal
low (40-60%). POPs in the Pittsburgh Metro peak between 25-40% on
Sunday and quickly fall off the further west you go. At this point
it looks as though northern and eastern counties see the highest
chances for showers during this time. Rainfall totals are likely to
be lower across our area, with most of the rain falling across our
eastern counties (0.25-0.50") and then a very sharp gradient
immediately west as totals decline to a few hundredths across the
remainder of western PA. Instability is quite low but there could be
a couple of rumbles of thunder Saturday night mainly north and east
of Pittsburgh as the Great Lakes upper low slides through the area.
High temperatures on Saturday are expected to be in the middle 60s
across the north with more stout cloud cover closer to the
approaching trough and ramping up to the low 70s as you move farther
south. The gradient in temperatures becomes more east-west oriented
by Sunday as the upper trough settles across Pennsylvania. High
temperatures Sunday and Monday are expected to be near normal
(mainly 60s) across western PA but slightly above average (upper
60s/lower 70s) across eastern OH.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
KEY MESSAGES:
- Dry/warm weather continues into Tuesday
- Uncertainty builds mid-week with large-scale pattern
-------------------------------------------------------------------
A persistent ridge axis east of the Rocky Mountains, reaching
into the Ohio River Valley, will bring dry weather and warmer-
than-average temperatures through Tuesday.
By mid-week, it remains uncertain if a trough will form over the
Great Lakes or if the ridge will stay, and long-range ensemble
temperatures indicate about a 10-degree spread between the 25th
and 75th percentile. Should a trough pattern dominate, freezing
conditions could return, accompanied by lake-enhanced
precipitation under a northwest flow.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR and clear skies continue this afternoon and VFR is expected
to continue through the TAF period as high pressure over the
Northeast drifts eastward. Southerly winds are expected to
remain light.
Clear skies again tonight hint at the possibility of steam fog
development over the rivers but impacts to ports appear short-lived
and minor at best. Mid-level clouds begin to build into our
north and west late tonight with an approaching trough.
.OUTLOOK...
Restriction and shower potential returns Saturday night through
early Monday as an upper level low tracks southeast across the
region.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.
&&
$$
SYNOPSIS...Shallenberger/AK
NEAR TERM...Shallenberger/AK
SHORT TERM...Shallenberger/AK
LONG TERM...Hefferan
AVIATION...Rackley

NWS PBZ Office Area Forecast Discussion