274
FXUS61 KPBZ 071145
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
745 AM EDT Mon Sep 7 2026

.WHAT HAS CHANGED...
Update to Key Message 1.

&&

.KEY MESSAGES...
1) A passing trough Wednesday into Thursday returns showers and
thunderstorms to the region

&&

.DISCUSSION...
KEY MESSAGE 1...
Confidence remains high that quiet and dry weather will persist
today and tomorrow as high pressure remains over the Great
Lakes and Ohio River Valley. Temperatures will remain near to
slightly above climatological averages, supported by deep
northwesterly flow on the backside of a trough.

Long-range models depict a pattern change Wednesday into
Thursday as low pressure develops and strengthens over the
Pacific Northwest and tracks eastward into southern Canada and
the Great Lakes. This system will weaken the ridge over the
central CONUS and allow more active weather to develop across
the region.

Temperatures will trend above average Wednesday as southwest
flow returns, with dew points rising into the mid to upper-60s
and resulting in increasingly muggy conditions. Heat index
values could approach 90 degrees by late Wednesday afternoon in
a few areas. By late Wednesday into early Thursday morning,
precipitation chances will increase as a trough and associated
cold front moves across the Great Lakes. The probability of
strong to severe storms is currently around 5-15%.

The prolonged passage of the trough may support periods of
moderate to heavy rainfall totals on Thursday, potentially
resulting in isolated flooding near creeks and streams. Some
areas could receive 1 to 1.5 inches of rainfall during this
period.

Drier conditions are expected Friday with the exit of the cold
front and a building ridge.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
High confidence in mostly VFR conditions as high pressure
remains in control. Patchy valley fog will largely dissipate by
13Z, and isolated to scattered afternoon cumulus are expected at
most. Generally light northeast to east wind is forecast.

Outlook...
Restrictions will likely return early Thursday into Friday with
a passing cold front; rain showers and thunderstorms are
expected.

&&

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

&&

$$

DISCUSSION...Hefferan
AVIATION...CL