584
FXUS61 KPBZ 170618
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
218 AM EDT Wed Sep 17 2025

.SYNOPSIS...
Other than a shower or two in the higher elevations this
morning, high pressure will keep the weather warm and dry into
the upcoming weekend. Rain chances return to the forecast next
week, though the chance for widespread wetting rain remains low.

&&

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

- An isolated light rain shower or two through the morning in
  the higher elevations; otherwise dry
- Continued above-normal temperatures
---------------------------------------------------------------


Low pressure tracking northward up the eastern seaboard is
expected to degrade to an open wave as it meanders towards New
England. A shower or two may linger in the Laurels/WV ridges
this morning, but any minimal rain chances will end this
afternoon as the system departs. Elsewhere, dry weather
continues to dominate the forecast under the influence of high
pressure. Highs this afternoon once again reach the low to mid
80s except for the higher elevations east of Pittsburgh, where
more dense cloud cover associated with the passing low will
help keep temperatures in the 70s.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
KEY MESSAGES:

- Dry weather and above normal temperatures continue
--------------------------------------------------------------

The departing trough kicks out into the Atlantic by Thursday
night in response to building mid-level ridging over the Lower
Ohio Valley. Clouds will pull east with time, leading to mostly
clear skies Thursday and Thursday night save for some scattered
diurnal cumulus in the afternoon. This, combined with height
rises due to the building ridge, will allow for stronger
heating/mixing and high temperatures climbing back to around 10
degrees above normal (mid 80s areawide). Overnight lows continue
to trend just a few degrees above normal as the dry air allows
for more efficient radiative cooling. Can`t rule out some patchy
river valley fog during late night and early morning hours with
calm winds and clearing skies.

&&

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

- Still dry and warmer than normal through the weekend
- Minimal rain chances return early next week
- Temperatures slightly cooler but still above normal Monday and
  Tuesday
------------------------------------------------------------------

The dry pattern continues into the weekend with high confidence
as the upper ridge axis crosses the Upper Ohio Valley. The
passage of a weak frontal boundary on Friday will do nothing to
dent the developing drought. With the continued rise in 500mb
heights, temperatures around 10 degrees above normal are still
expected for much of the area, save for I-80 north where slightly
better cold advection behind the weak front helps temperatures
remain slightly cooler - around 5 degrees above normal.

Ensembles are continuing a slowing trend with the approach of
the next upstream trough. Differences remain, but it appears
that the axis of the disturbance remains back over the Upper
Midwest and lower Ohio Valley during the Sunday/Monday period.
This leads to a downward trend in the already low PoPs that were
in place, with only a sub-20 percent chances mentioned north
and west of Pittsburgh through Monday. By Tuesday, uncertainty
in the depth and position of the shortwave continues to grow,
but clusters still show decent confidence in only a minor
eastward displacement, resulting in only slightly better rain
chances (20% areawide, 30% north of I-80). For now, there
remains little potential for a much-needed widespread wetting
rainfall.

This uncertainty extends to the temperature forecast as well. A
faster/slightly deeper trough could lead to temperatures closer
to climatology, while the slower solutions would continue the
warmer pattern. This latter solution seems more likely given the
ongoing dryness and better ensemble support, so temperatures
close to 10 degrees above normal have been maintained in the
forecast.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
High confidence VFR continues through the TAF period as high
pressure remains across the region. Winds will remain light and
variable, though generally easterly. Mid/High level scattered
cloud coverage will continue to filter in, associated with a
coastal surface low near SE Virginia.

Cloud coverage should mitigate most fog potential this morning.

.OUTLOOK....
High pressure will continue to dominate the weather pattern,
promoting VFR and light easterly wind. Clear sky nights may
result in patchy river fog during the pre-dawn hours.

&&

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

&&

$$

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