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986
FXUS61 KPBZ 281210
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
810 AM EDT Sat Jun 28 2025

.SYNOPSIS...
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Flooding and isolated damaging wind risks will be possible ahead
of slow front this afternoon. Dense fog potential early tomorrow
morning. Drier weather is expected Sunday, followed by another
active period Monday to Tuesday.
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&&

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

- Warm and wet pattern continues today
- Downburst wind and flooding threats increase after 1pm today
- Dense fog potential increases after midnight

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A few isolated showers have developed early this morning, likely
triggered by lingering outflow boundaries from the past 12
hours. A cold front currently stretches across northern Ohio,
with a few thunderstorms forming along it--bringing heavy
rainfall and occasional non-severe wind gusts.

This advancing cold front will serve as the main focal point
for convective initiation this afternoon in our region,
initially along the I-80 before advancing southeast. Ensembles
continue to advertise plentiful instability (1500-2500 J/kg of
sfc-based CAPE) in a low-shear environment. A bit more dry air
aloft, along with potential for 600-800 J/kg of DCAPE, will
present an isolated downburst wind threat once again. PWAT
values also remain high, which indicates potential for more
heavy rainfall and localized flash flooding with training storms.
WPC has maintained a Marginal Risk for excessive rainfall
across most of the area.

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 most of the area rain-free by
midnight.

However, with abundant residual moisture in the boundary layer,
calm surface winds, and some clearing skies will increase the
potential for fog development after midnight.
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&&

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

- Early morning fog Sunday
- Mostly dry conditions Sunday
- Storm and heavy rainfall chances return Monday and Tuesday.
- Temperatures remain above-average, but below heat advisory
  criteria.

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

Fog is expected to linger across the region early Sunday morning
through at least 8am. The fog could be dense at times and may
prompt either a Special Weather Statement or a Dense Fog
Advisory.

The cold front is expected to stall just south of the Mason-
Dixon line on Sunday, keeping most showers and storms south of
our area. The exception may be a few showers/storms across the
WV ridges Sunday afternoon. Temperatures will remain above-
normal under increasingly zonal 500mb flow.

The front will begin to lift back northward late Sunday night
into Monday, with showers likely returning to the area Monday
morning. Elevated PWATs with southwesterly flow and plentiful
instability will again mean flooding low-end severe threats are
on the table. WPC has maintained a Marginal Risk for excessive
rainfall Monday/Monday night. Rain will finally clear with
another cold frontal passage Tuesday, leaving drier conditions
for the remainder of the day. Northwesterly flow and meager cold
advection will keep temperatures closer to seasonal norms
Tuesday afternoon.
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&&

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

- A drier and more seasonable air mass arrives by Wednesday and
  persists through at least Thursday.
-
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The break in our more active pattern continues Wednesday into
Thursday as temperatures return to a more seasonable level under
quasi-zonal flow aloft. Low probability rain chances may return
Thursday afternoon and Friday as more wavy mid-level flow
develops. Details and timing remain unclear at this point.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...

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Shower and thunderstorm development is expected mainly after 18Z
as a slow moving cold front advances from the north. However,
stray showers can`t be ruled early this morning, triggered from
remnant outflow boundary over the last 12 hours. Have put in
some PROB30 to account for this development into the afternoon
at just about all the terminals. Development should wane and
dissipate between 00Z to 03Z.

With potential clearing, light winds, and an abundant amount of
remnant moisture near the surface the potential of fog increases
across the region. Fog could be dense at times, mainly between
the time period of 08Z to 11Z. Surface heating will likely help
improve vis conditions after 12Z.

Probability of showers and storms is elevated south of HLG with
a stalled frontal boundary on Sunday. Out of all the terminals,
MGW would be the most likely candidate to experience a few
stray showers.

Outlook... Showers/storms return again Monday with an
approaching cold front.
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&&

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

&&

$$

SYNOPSIS...Hefferan/Rackley
NEAR TERM...Hefferan/Rackley
SHORT TERM...Rackley
LONG TERM...Rackley/CL
AVIATION...Hefferan/Shallenberger