392
FXUS61 KPBZ 040556
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
156 AM EDT Sat Oct 4 2025

.SYNOPSIS...
High pressure remains dominant through Monday, leading to
continued dry weather and warm temperatures. The next chance of
a wetting rainfall arrives Tuesday into Wednesday.

&&

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

- Dry weather continues under high pressure.
- Highs will run 10-15 degrees above average, while lows remain
  just above normal.
-------------------------------------------------------------

Quiet and dry weather continues this morning and through tonight
with upper ridging over the eastern CONUS and surface high
pressure positioned just off the Mid-Atlantic. Weak warm/moist
advection in southerly flow on Friday has subtly increased
boundary layer moisture. With calm winds through sunrise, patchy
river valley fog is be possible in some areas.

Continued warm advection and sunny skies will boost area high
temperatures another 3-6 degrees above Friday observations,
putting most of the region in the lower 80s this afternoon. This
is 10 to 15 degrees above the climatological average. Despite
this, overnight lows will once again cool to just above-average
amid dry conditions, calm/light wind, and mostly clear sky.

&&

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

- Continued dry weather under high pressure
- Temperatures continue to run warmer than seasonal normals,
  especially during the afternoon.
----------------------------------------------------------------

There continues to be high confidence in the current pattern
holding through the weekend, with an upper ridge slowly shifting
eastward across the Ohio Valley and the Appalachians. This will
maintain above-seasonal temperatures and dry weather under
mostly clear skies. Daytime high temperatures will trend 10 to
15 degrees above climatology, while overnight lows will be
closer to (but still slightly above) climatology thanks to the
combination of dry air, clear skies, and light winds allowing
for efficient radiational cooling.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
KEY MESSAGES:

- High confidence in dry and warm conditions Monday
- Good chance of a wetting rainfall Tuesday into Wednesday
- Cooler temperatures from Tuesday on, although it is uncertain
  exactly how much cooler values will be
----------------------------------------------------------------

Clustered ensemble guidance continues to show a high-confidence
pattern for Monday, with the main ridge axis along the Eastern
Seaboard during the morning. This will maintain the dry and warm
pattern for one more day.

Thereafter, guidance generally agrees that an upper trough
pushes across the Great Lakes Tuesday/Tuesday night and
reaches the northeast CONUS by Wednesday. Differences remain
among the various ensembles regarding depth and timing of this
trough, particularly impacting confidence in temperatures. NBM
10th to 90th percentile max temperature spreads are near or over
10 degrees from Tuesday on, with values from a bit below to a
bit above normal all plausible. The current forecast will
continue to mirror the ensemble means, which are near normal
this time of year.

Despite the model differences, this trough still represents the next
decent chance of a widespread rainfall. NBM 48-hour probabilities of
half-inch or more of rain ending at 8 AM Thursday are in the 50
to 60 percent range for the Upper Ohio Valley. This will not be
a drought-ending event by any means, but a welcome wetting
rainfall does appear to be an increasingly likely outcome.
Precipitation timing favors the Tuesday afternoon to Wednesday
morning window, though it could start in eastern Ohio as early
as Tuesday morning and linger in the WV/PA ridges as late as
Wednesday afternoon.

Upper ridging and subsequent dry weather settles in following
the midweek system, but only briefly as ensemble guidance
suggests another upper trough or low pushes into the Great
Lakes and lower Ohio Valley on Friday, bringing precip chances
back to the area as we head into next weekend.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
Patchy river valley fog is possible near dawn, but unlikely to
impact most ports. Probability is highest at LBE, and have
included TEMPO MVFR vsby restrictions there. Otherwise, mostly
clear skies with light wind are expected through the period as
sfc high pressure and ridging aloft remain in control.

.OUTLOOK....
VFR conditions are expected on the whole through Mon as high
pressure centered in the nern CONUS remains assertive. The
exception will be during late night/early morning Sun and Mon
when river-valley fog could ensue coincident with increasing
boundary-layer moisture and diurnal slackening of the wind.

&&

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

&&

$$

SYNOPSIS...CL
NEAR TERM...Rackley
SHORT TERM...Cermak/CL
LONG TERM...Cermak/CL
AVIATION...Rackley