646
FXUS61 KPBZ 090010
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
810 PM EDT Fri Aug 8 2025

.SYNOPSIS...
High pressure will remain anchored over the northeast states
through the weekend bringing mainly dry weather and a gradual
warming trend. A slow moving front will drift into the area
Tuesday through Friday bringing shower and thunderstorm chances
back to the Upper Ohio River Valley.

&&

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

- Dry weather with seasonable temperature continues
---------------------------------------------------------------

1027 mb surface high has been anchored over New England with
surface ridge extending into the forecast area. There is diurnal
cumulus and some of the guidance suggests that showers could
form over the ridges. Probability of measurable rain in any one
place is less than 10% so nothing is mentioned in the base
forecast products. Skies have been a tad hazy, likely due to old
Canadian smoke trapped under the subsident surface high.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
KEY MESSAGES:

- Temperature will rise above normal over the weekend, but
  limited moisture should keep heat indices below criteria.

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

Surface ridge will remain in place and gradually weaken during
the period as it slowly moves southeast. The upper ridge will
also build up the Ohio Valley into the Northeast with heights in
the 5920 meter range, allowing temperatures to push into upper
80s to lower 90s. Dew Points will be mainly in the 60s, so heat
indices should remain below 100F so no headlines appear needed
at this time.

&&

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

- Rain chances increase areawide Tuesday and Wednesday, although
  uncertainty in coverage and timing exists
-------------------------------------------------------------------

Guidance has a trough coming across the Great Lakes on Tuesday
and Wednesday with variance in timing and intensity. In some
cases the ensembles have just a slight flattening of the top of
the ridge, which would result in less thunderstorm chances. The
increase in moisture should lead to at least scattered diurnal
thunderstorm chances as ensembles show Precipitable Water values
increasing into the 1.6 to 2.0" range with diurnal SBCAPE values
climbing above 1,000 j/kg. NBM probabilities of 0.25 to 0.50" do
increase quite a bit so the current probabilities in the 30 to
60% range seem reasonable.

Confidence in forecast for Thursday and Friday is rather low at
this time. Guidance varies on whether ridging or troughing will
dominate, and whether the flow will be southwesterly or
northwesterly aloft. So large spread in possibilities and not
much to offer other than waiting for guidance to come into
better agreement.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Light to calm wind expected overnight with the loss of the cu
deck. A few cirrus may stream by but otherwise an unimpactful
night. Some valley fog is possibly in the morning hours, but
given persistence from the past several nights, probability of
impacts to any given terminal is low. Included mention of MVFR
haze at AGC during early to mid morning Saturday before the
onset of daytime heating and mixing should help to raise
visibilities back to VFR, similar to this morning.

Outlook...
VFR is generally expected through Monday under a ridge of high
pressure. Low chances for showers and thunderstorms return
Tuesday as a cold front approaches.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...Air Quality Alert until 11 PM EDT this evening for WVZ001>004-
     012-021-509>514.

&&

$$

SYNOPSIS...Craven
NEAR TERM...Craven
SHORT TERM...Craven
LONG TERM...Craven
AVIATION...Cermak/MLB