020
FXUS61 KPBZ 111101
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
701 AM EDT Mon Aug 11 2025

.SYNOPSIS...
Dry and hot weather is expected through early Tuesday under
high pressure. Minimal shower and thunderstorm chances return
Tuesday afternoon, with better chances expected on Wednesday
with a weak cold front.

&&

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

- Hot conditions continues
- 14 straight days of dry weather for Pittsburgh
---------------------------------------------------------------

Morning Update: No major changes have been made to this forecast
period.

Previous Dicussion:

Surface high pressure remains centered off of the Mid Atlantic
coast, with an upper level ridge across the Upper Ohio Valley
region. This should maintain dry weather across the region
today. Expect a diurnal cumulus layer to develop by late
morning/early afternoon as convective temperatures are reached.

500 mb heights are expected to similar to yesterday (around 592
dm), with 850 mb  temperatures slightly higher (16-18 deg C.)
This should result in high temperatures a degree or two warmer
than Sunday`s readings. However, index values will likely stay
below 95 degrees.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
KEY MESSAGES:

- Hot with minimal shower/storm chances Tuesday
- Better shower and thunderstorm chances Wednesday
----------------------------------------------------------------

The ridge will remain in place through much of Tuesday, before
beginning to break down later in the day. Model soundings show
capping warm air aloft in place through at least the first half
of the day, with some erosion of the cap in the afternoon. A
few showers and thunderstorms could develop as convective
temperatures are reached, though expect coverage to be minimal
with a lack of forcing.

A shortwave trough, and its associated weak surface cold front,
will advance eastward from the Midwest Tuesday night and
Wednesday. The shortwave will maintain some chance for showers
Tuesday night as it approaches. A thunderstorm is also possible
with limited elevated instability in place.

Higher chances for showers and thunderstorms are expected on
Wednesday as the shortwave trough and weak surface front cross
the Upper Ohio Valley region. The 0-6km shear is expected to be
around 20kt, with stronger flow staying north of the area.
Current model progs indicate a ML CAPE from 1000-2000 j/kg by
afternoon, with some mid level dry air in place. This mid level
dry air could result in a gusty wind/downburst potential in
stronger, more organized storms. PWATS are expected to
increase, ranging from 1.6 - 1.9. Some locally heavy downpours
will be possible, but given the dry antecedent conditions do
not currently expect any significant flood potential. Showers
and thunderstorms should taper off Wednesday night as the
shortwave exits, and the surface front drifts southeastward.

Temperatures are expected to reach the upper 80s to the lower
90s across much of the area on Tuesday, outside of the ridges.
The combination of heat and humidity should result in heat
index values ranging from 90 to 95, which would remain below
advisory criteria. Clouds and shower/storm chances should hold
temperatures in the 80s on Wednesday.

&&

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

- Lingering shower and thunderstorm chances Thursday
- Generally dry and hot Friday through the weekend
-------------------------------------------------------------------

There is some uncertainty on the position of the weak surface
boundary on Thursday, and how fast it will exit the region. A
secondary weak shortwave is progged to track along the front,
generally from near PIT and southward, through the day. This
should keep some chance for showers and thunderstorms across
the area south of I-80 through the afternoon. The shortwave
will exit the area by Thursday evening, with the resulting NW
flow aloft driving the weak boundary south.

Model ensembles have trended toward a stronger ridge across
much of the eastern CONUS Friday through the weekend. This
should maintain dry and hot weather across the Upper Ohio
Valley region.

Highs on Thursday should be in the lower to mid 80s, with
readings returning to between 5 and 10 degrees above average
again Friday into the weekend.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
Persistence forecast due to continued presence of surface
high pressure calls for VFR, few afternoon cumulus between
5-7kft, subtle southerly wind, and dry weather.

Outlook...
The approach of an upper trough may foster isolated convection
Tuesday before more widespread rain chances develop Tuesday
night into Wednesday with its passage. Look for restrictions to
be closely tied with storm occurrence (which may also foster
erratic, gusty wind).

A downward trend in rain potential is favored to end the week
as high pressure develops near New England.

&&

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

&&

$$

SYNOPSIS...WM
NEAR TERM...WM/Hefferan
SHORT TERM...WM
LONG TERM...WM
AVIATION...Frazier