380
FXUS61 KPBZ 022322
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
722 PM EDT Wed Jul 2 2025

.SYNOPSIS...
Valley fog is possible tonight, with isolated thunderstorms
expected Thursday afternoon, with dry weather for the Fourth and
Saturday. Temperatures will gradually climb into the lower 90s
through the weekend into the start of next week.

&&

.NEAR TERM /UNTIL 7 AM THURSDAY MORNING/...
KEY MESSAGES:

- Patchy valley fog tonight.
---------------------------------------------------------------

Any lingering clouds will dissipate with the loss of mixing this
evening and early tonight, giving way to mostly clear skies and
light to calm wind. This efficient cooling might suggest lows
around average, dropping to near dewpoint observations in the
lower 60s and upper 50s. As temperatures approach dews, fog will
be possible; most likely in river valleys and sheltered
surrounding areas. Fog will burn off after sunrise.

&&

.SHORT TERM /7 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
KEY MESSAGES:

- Slight chance for showers and thunderstorms Thursday, mainly in
the northern PA counties.
- Dry and sunny weather for the Fourth.
- Temperatures a few degrees above average.

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A trough and its associated surface cold front, is expected to track
southeastward across the Upper Ohio Valley region on Thursday. Very
dry air aloft will likely inhibit updraft growth, limiting the
chance for showers and thunderstorms. Still, isolated thunderstorms
are possible (30%-45% chance) over the following PA counties:
Forest, Venango, Butler, eastern Mercer, Clarion, Jefferson,
Armstrong, Indiana, and northeastern Allegheny.

Given the dry air aloft and substantial surface-based CAPE, there
will be a conditional threat for downbursts IF more robust updrafts
are able to develop. Machine learning guidance does marginally
support a low-end severe weather threat as well. Will continue to
monitor this threat. Any convection will quickly diminish after
sunset with loss of daytime heating.

Afternoon temperatures forecast to be few degrees above seasonal
average, while temperatures Thursday night may drop a degree or two
below average.

Beautiful weather looks to be in store for the Fourth with sfc high
pressure and ridging overhead. Models do develop a few isolated
diurnal showers and thunderstorms in Ohio, but this is likely to
remain west of Coshocton and Muskingum counties. Otherwise, the
forecast looks great for outdoor plans and evening fireworks.
Temperatures will run no more than 5 degrees above average under
partly to mostly sunny skies, and heat indices in the mid to upper
80s outside of the ridges. Temperatures fall back to near-normal
Friday night.

&&

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

- Dry on Saturday.
- Increasingly hot and humid with shower and thunderstorm
  chances returning Sunday and Monday.

-------------------------------------------------------------------

Sfc high pressure and ridging aloft should promote mainly dry and
warm weather again Saturday. Rising heights and southerly flow
should boost area highs into the upper 80s to near 90F. NBM probs
for 90F are highest across eastern Ohio, northern West Virginia
panhandle, and the Pittsburgh urban heat island (70%-85%). For other
areas, probabilities are generally around 35%-45% or lower in the
higher elevations.

The ridge is then progged to flatten Sunday into early next week,
with westerly flow aloft across the Upper Ohio Valley region.
Disturbances embedded in this flow aloft are expected to
periodically cross the region, with daily shower and thunderstorm
chances returning.

On Sunday and Monday, 500 mb heights are still expected to approach
590 dam, bringing hot and humid conditions across the region. High
probability (70%-90%) of maximum temperatures at or above 90 degrees
on Sunday and Monday. The chances of Heat Advisory criteria remain
low as heat indices remain in the 90s.

&&

.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
Remaining diurnal clouds will dissipate during the early
evening, with patchy high clouds overnight. Fog is forecast to
be less widespread Thursday morning, confined mainly to valley
locations, especially east of PIT. Included mention at MGW and
LBE for now, with potential MVFR/IFR impact.

Any valley fog should dissipate by 13Z, with scattered to broken
VFR cumulus once again by midday. A cold front dropping south
into the region during the afternoon may support isolated to
scattered showers/thunderstorms after 18Z, although moisture
depth is limited overall. Used a PROB30 at DUJ, the site with
the best chance of being impacted, and closest to a shortwave
dropping southeast across New York State. Mention may be needed
at other sites like FKL, LBE, and potentially even PIT/AGC if
future hi-res runs indicate better coverage potential.

Light and variable wind overnight will take on more of a
northwesterly direction under 10 knots by late morning.

Outlook...
VFR is expected through Sunday as high pressure moves across
the region, with precipitation chances and isolated restrictions
potentially returning Monday.

&&

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

&&

$$

SYNOPSIS...Rackley/Lupo
NEAR TERM...Milcarek
SHORT TERM...Rackley/Lupo
LONG TERM...Rackley/Lupo
AVIATION...CL