082
FXUS61 KPBZ 300535
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
135 AM EDT Wed Jul 30 2025

.SYNOPSIS...
Hot and humid through Wednesday with daily storm chances.
Cooler and drier Friday and beyond.

&&

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

- Warm and muggy overnight hours with lows 10 degrees above
  normal.
- Areas of fog likely by morning.
---------------------------------------------------------------

Coverage of showers and storms has now waned in our area with
the last convective cluster sliding south out of our northern
West Virginia counties. In its wake, dry weather will take hold
overnight with a weak gradient providing light to calm wind and
some streaks of cirrus.

Continued heat is expected overnight with lows nearly 10 degrees
above normal in bountiful near-surface moisture. Patchy fog is
likely yet again, likely most dense in northern West
Virginia/far southwestern Pennsylvania where the most rain fell
today; in areas where the 12z HREF had rain this afternoon,
probability for dense fog is elevated as high as 60%.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
KEY MESSAGES:

- Hot and humid with some storm chances carrying low-end flood
  and severe threats.
----------------------------------------------------------------

In the last 24 hours, both the overall coverage of rain as well
as the severe/flooding threats have trended down across the
area with a gradual weakening trend in the shortwave and a
response in CAMs showing less convective coverage. Coverage is
expected to be isolated to scattered at best, with the best
chances in the ridges with orographic uplift.

The more interesting tidbit is that HREF 25th to 75th
percentile SBCAPE is 1000 J/kg to 3000 J/kg and DCAPE is 1000
J/kg to 1300 J/kg. Suggesting there is severe wind potential
conditional on mature storm development, but at this point this
remains low probability, as the degree of dry air aloft may also
be inhibitive of updraft grown itself with entrainment in an
environment with otherwise lack-luster forcing apart from pulse
convection. The only way we materialize severe potential may be
a strong enough outflow or multiple storms wet-bulbing a local
environment. For flooding, with weak flow and PWATs nearer the
75th percentile, it is possible, but low probability and
conditional on training. Major heat risk continues Wednesday for
most with daytime maximum heat indices in the mid-to-upper 90s,
touching 100F in isolated urban and valley locations that do
not see rain.

As the main front itself drops through on Thursday, the theta-e
gradient is likely to tighten, and forcing will be stronger for
the presence of storms themselves. As moisture rides up
southwest flow preceding the frontal passage, PWATS will
heighten to roughly the 1.8" to 2" range, though flow on the
front will be generally 20kts to 30kts. This will maintain a
marginal flood threat for training segments. This moisture
keeps DCAPE relatively low in the 400 J/kg to 600 J/kg range,
not to say that a linear, shear- oriented, strong cell
accelerating on the front couldn`t produce severe winds, though
at this time, it just remains low predictability.

Temperatures actually trend closer to normal on Thursday night
behind the cold front with surface dew points dropping
accordingly. This will leave the region comfortable with patchy
fog by daybreak Friday.

&&

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

- Dry and cool this weekend.
-------------------------------------------------------------------

There is high confidence in a seasonably cool and dry airmass
behind the cold front passage Friday and into Saturday.
Clustered height fields in in the eastern CONUS all have less
than 2dm of height variability, indicating high confidence in
this pattern.

There is also high confidence this pattern relaxes quasi-zonal
into early next week over top of a flat central CONUS ridge.
This might allow for a gradual warming to near normal with
increasing, but still low, chances of rain.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Fog development will be most dense over areas that received
rainfall, particularly south of KPIT. Dry conditions are
expected today but an isolated thunderstorm can`t be ruled out
south and east of KPIT. Light and variable winds will remain.
Fog development will be possible again during the upcoming
night.

Outlook...
Precipitation and restriction chances become more
widespread into Thursday with the approach and passage of a cold
front.

High confidence in a prolonged period of VFR (save for more
river valley steam fog) with dry weather Thursday night into the
weekend.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...Heat Advisory from noon today to 8 PM EDT this evening for
     OHZ068-069.
WV...Heat Advisory from noon today to 8 PM EDT this evening for
     WVZ012-021-509.

&&

$$

SYNOPSIS...Milcarek
NEAR TERM...MLB/Milcarek
SHORT TERM...Milcarek
LONG TERM...Milcarek
AVIATION...88