695
FXUS61 KPBZ 052345
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
745 PM EDT Sun Oct 5 2025

.SYNOPSIS...
Dry and warm weather continues through Monday under high
pressure. A passing cold front returns rain Tuesday and Tuesday
night ahead of a dry rest of the week and more seasonable
temperatures.

&&

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

- Dry and warm
---------------------------------------------------------------

Clear skies remain overnight with a light south wind as high
pressure is anchored over the Northeast. Lows will dip into the
low to mid 50s, which is also near 10 degrees above average.
Akin to previous nights, expect some river valley fog
development for Monday morning with little impact away from the
valleys.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
KEY MESSAGES:

- Dry and warm weather continues into Monday night
- A soaking rain appears more likely Tuesday afternoon and night
----------------------------------------------------------------

One more dry and warm day is forecast for Monday. The upper
ridge axis pushes off into the Atlantic, with our region still
on the western periphery. Southwest flow does start to moisten
the column somewhat, leading to some afternoon mid-level clouds.
Above-normal temperatures will be maintained, with many areas
in the lower 80s once again. Low temperatures Monday night will
be particularly mild with more cloud cover, with some locations
not dipping below the lower 60s.

The moisture increase continues through Monday night and Tuesday,
eventually leading to precipitable water values around 1.5 inches by
Tuesday evening, near the top end of climatology. This occurs in
ongoing southwest flow, which also provides increasing isentropic
lift. Also, a cold front extending from low pressure well to our
north, in eastern Canada, will approach Tuesday and likely cross the
region Tuesday night. All of this provides our next good chance of a
needed area-wide soaking rainfall. Some light rain is possible prior
to sunrise Tuesday, especially west of Pittsburgh. Still, it will
take some time for steadier rainfall to develop, particularly
considering the antecedent dry air mass and the strength of the
departing ridge. Tuesday afternoon into Tuesday night appears to be
the prime period.

Recent NBM runs are showing higher confidence in soaking rainfall
totals.  System-total probabilities of 0.50" or higher range from 75
to 90 percent, with 1" or more coming in at 30-50 percent. These
amounts will still not a drought-buster, but this will certainly be
helpful. Locally higher totals than an inch will certainly be
possible in any convective elements. Flooding is not considered to
be a threat with the dry antecedent conditions and low stream/river
levels, outside of perhaps very isolated issues in urbanized or poor
drainage areas (clogged drains/culverts from falling leaves in
particular). Some rumbles of thunder are possible during the day
Tuesday in very modest instability, but poor lapse rates/dynamics
and the lack of surface heating should render severe weather a non-
existent threat. Temperatures should be suppressed to just a few
degrees above normal Tuesday/Tuesday night ahead of FROPA.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
KEY MESSAGES:

- Dry weather returns Wednesday with gusty wind
- Temperatures fall to seasonal normals
- Dry weather most likely Friday into the weekend, but pattern
  uncertainty increases
-------------------------------------------------------------------

Ensembles have been trending a touch faster with the boundary,
kicking it out early enough to end precipitation across most areas
by 12Z Wednesday and to provide a mostly sunny sky by afternoon.
Still, a morning shower or two in the northern WV ridges cannot be
ruled out. The cooler air mass will provide temperatures right
around seasonal norms. Northwest wind behind the front should be
gusty behind the front given good mixing and a tightening pressure
gradient. The NBM suggests maximum gusts in the 25 to 30 MPH range
for most of the region.

Flow aloft transitions to a zonal pattern in the wake of the
departing shortwave trough, with surface high pressure traversing
the Great Lakes into the northeast CONUS. This should keep
conditions dry through Thursday night. Low temperatures below
climatology are indicated for Wednesday night, and the sky will
remain clear, but it is questionable whether the surface pressure
gradient relaxes enough to allow for nearly calm wind and good
radiational cooling. This could limit frost potential Thursday
morning, even though some areas could drop into the mid 30s north of
US-422. Temperatures closer to normal are likely for Thursday and
Thursday night, with increasing high cover during the latter period.

Uncertainty in the flow pattern begins to increase Friday and
through the weekend. The majority of ensemble cluster members seem
to favor baggy troughing over the eastern CONUS, with a minority
showing notably higher 500mb heights. The differences magnify for
Saturday and Sunday, as trough/ridge positioning and strength vary.
Overall, most solutions do not seem to favor notable surface systems
that would provide much in the way of precipitation, so a mostly dry
forecast will be maintained for now, in line with NBM suggestions.
Temperatures near or slightly above climatology for this
period currently appear to be the most likely outcome.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
High confidence VFR continues under high pressure and mid-level
ridging. Clear and calm conditions along with persistence nod
towards isolated river valley fog development but impacts are
low probability.

High pressure begins to push eastward tomorrow and a slight
SWerly wind will support increasing moisture that can bring mid-
level clouds to the region amidst continuing VFR.

.OUTLOOK...
Restrictions in showers and a possible thunderstorm are
expected Tuesday and Tuesday night with a crossing cold front.
Wind gusts will be elevated on Wednesday in the wake of the
boundary. VFR then returns through late week under building high
pressure.

&&

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

&&

$$

SYNOPSIS...MLB/CL
NEAR TERM...Rackley/MLB
SHORT TERM...CL
LONG TERM...CL
AVIATION...AK