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916
FXUS61 KPBZ 280357
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
1157 PM EDT Fri Jun 27 2025

.SYNOPSIS...
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Showers and thunderstorms will diminish through the overnight.
Flooding and isolated damaging wind risks will be possible again
on Saturday. Rain chances decrease Sunday, followed by another
active period Monday to Tuesday. Temperatures return to near
normal and conditions trend slightly drier mid- week.
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&&

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

- Showers and thunderstorms diminish this evening.
- Warm overnight temperatures continue.

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

The severe and flooding threats have ended for the night, though
a few scattered showers and thunderstorms remain this evening.
These should continue to diminish over the next several hours,
leaving dry, but warm and humid weather for the remainder of the
overnight. CAMs do introduce low PoPs early this morning
associated with the storms currently moving over Lake Erie and
Ontario, but this activity looks to remain north of our area.
Localized fog development is possible through dawn.

Overnight low temperatures remain roughly 10 degrees above
average.
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&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
KEY MESSAGES:

- Downburst wind and flooding threats in the afternoon and
  evening continue on Saturday.
- A frontal passage leads to a temporary break in the active
  weather pattern later Saturday night through Sunday.
----------------------------------------------------------------

General model consensus continues to show a cold front
extending from eastern Canada low pressure crossing the region
generally during the peak heating period on Saturday. The HREF
advertises a 70- 85% probability of at least 1500 J/kg of
surface-based CAPE in a continued low-shear regime. Although
precipitable water values appear to back off slightly, into the
1.7" to 1.8" range, there certainly will continue to be a threat
of flooding, particularly east of a DUJ-PIT/ZZV line where
convective coverage is likely to maximize ahead of the front and
where soils may be even more saturated after today`s activity.
A bit more dry air aloft returns to model soundings, along with
potential for 600-800 J/kg of DCAPE, will present another
isolated downburst wind threat. Given the cloud and rain
coverage, heat indices should remain low enough to preclude any
extension of heat-based headlines into Saturday.

The passage of the boundary and the diurnal loss of instability
should lead to decreasing convective coverage from north to south
during the evening, with perhaps a precip-free CWA during the
predawn hours. Fog development may be an issue by sunrise.

The boundary is likely to stall near or just south of the Mason-
Dixon Line on Sunday.  Although a few showers/storms may be possible
in the southeast ridges, much of the region may be able to enjoy a
one-day break from the active weather pattern as surface high
pressure tracks just to our north. Temperatures will remain a bit
above normal as increasingly zonal 500mb heights remain
elevated. The front is likely to begin to lift back north later
Sunday night, with perhaps a few showers across our far southern
zones toward sunrise.

&&

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

- Potential for severe storms and locally heavy rainfall
  through at least Monday and possibly on Tuesday.
- A drier and more seasonable air mass arrives by Wednesday and
  persists through at least Thursday.
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There is general model agreement that, with the boundary lifting
north of the region again by Monday, precipitable water values
increase again on southwest flow along with instability. A flooding
threat and at least a low-end severe threat will likely continue
into Tuesday.

There is a likelihood of a frontal passage at some point during the
Tuesday/Tuesday night period that will finally kick this high-
moisture airmass definitively to the east. Although timing
differences remain, there is still generally decent ensemble
agreement on this break to the warm and rainy pattern. Temperatures
will also return to a more seasonable level as Wednesday and
Thursday generally remain dry in the more quasi-zonal flow aloft. So
low rain chances may return by Friday with a bit more wavy mid-level
flow developing.

&&

.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
Much of the first line of thunderstorms has cleared the area east.
Just LBE and DUJ begin with mentions of thunder in the east and both
are expected to be clear by 01z.

Out west storms continue to move in from the west and ZZV also
starts the TAF period with thunder. For all of these ports storms
can bring wind gusts between 30-40KTs and the possibility of reduced
VIS in heavy rain.

Storms are expected to wind down after sunset as we lose daytime
heating. VFR is expected to return for most ports but with recent
rainfall and high dewpoints the risk of fog looms, especially in the
areas of highest rainfall. The most likely ports for restrictions
are DUJ, FKL and LBE where probabilities of MVFR VIS are between 40-
70% between 06-12z.

CIGs will lower from the east Friday night, generally impacting
terminals north and east of PIT in the most saturation and in
proximity to a back- door cold front trapped on the leeward side of
the ridges. More shower and storm chances return tomorrow afternoon.

Outlook... There is a lesser potential for afternoon showers/storms
on Sunday as high pressure briefly brushes by to the north.
Showers/storms return again Monday with an approaching cold
front.

&&

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

$$

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