588
FXUS61 KPBZ 141638
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
Issued by National Weather Service Charleston WV
1238 PM EDT Wed May 14 2025

.SYNOPSIS...
A Flood Watch has been issued for excessive rainfall along the
ridges of Pennsylvania and West Virginia today with additional
showers and storms this afternoon and evening. There is the
potential for severe weather late this week ahead of a passing
cold front.

&&

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

- Showers and thunderstorms return this afternoon/evening
- Flood Watch in effect through 10pm tonight for Preston,
  Tucker, Westmoreland, and Fayette County for potentially slow
  moving storms; 1-2 inches possible
- Fog expected after midnight

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Mostly quiet conditions are expected through 3pm with weak
forcing and weak instability across the region. High resolution
models have been consistent that heavy rain, for showers and
storms, are expected to develop in central West Virginia
between 17Z to 20Z this afternoon and could cause training
along the ridges into the evening hours. With 1-2 inches of rain
over the last 24 hours in Fayette, Westmoreland, Preston, and
Tucker County, a Flood Watch has been issued through 10pm; some
areas could receive 1-2 inches of rain if storms train. Note,
PWATs still remain above average at 1.25 to 1.50 inches, which
is unseasonably moist for this time of year. Damaging wind gusts
are unlikely with DCAPE value trending below 300J/kg. Lightning
and heavy rain will be the main threat.

Probability of heavy rain and thunderstorms decreases after
10pm. However, there is a potential for fog with rich low-
level moisture and light winds. A Dense Fog Advisory may be
needed for the overnight time period.

&&

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

- A cold front approaches the area Thursday night into Friday,
  bringing a threat for strong to severe thunderstorms during
  that time.
- All modes of severe weather (damaging winds, hail, and
  tornadoes) appear possible at this time.

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A lead shortwave trough, ahead of a main central CONUS trough,
is expected to approach and cross the region late Thursday
night, along with its associated surface cold front. Speed and
directional shear is expected to increase with the approach of
the trough as instability is maintained Thursday night. Severe
storms are likely to develop to the west of the region late
Thursday, tracking eastward across the Upper Ohio Valley
Thursday night. The greatest uncertainty is the amount and
eastward extent of instability that remains across the Upper
Ohio Valley region, which would impact the severe weather
potential. Latest model data continue to indicate that these
storms could be maintained well into the overnight hours.

Model ensembles indicate a trough will track slowly eastward
across the Upper Midwest to the Upper Ohio Valley region Friday.
The surface front is expected to slow its progress as the upper
level flow becomes more parallel to the front. Enough
destabilization and shear is expected again by late Friday morning
and afternoon to support a threat for strong to severe storms.
Confidence is still low on the Friday threat, however, due to
the possibility that early morning convection (noted in the
paragraph above) impacts the afternoon near-storm environment.

&&

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

- Unsettled weather continues Saturday as a cold front crosses
  the area.
- High pressure and drier weather build in Sunday into early
  next week in the wake of Saturday`s cold front.
-------------------------------------------------------------------

The trough axis is expected to cross the region on Saturday,
with additional showers possible. Lower chances for showers are
expected on Sunday as the trough finally exits. A high amplitude
ridge forms over the central CONUS early next week between the
departing northern Atlantic trough to the east and another
trough deepening over the western CONUS. This pattern brings dry
weather back to the local area Monday into Tuesday.

&&

.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
An upper low will continue across the Ohio Valley today as it
weakens/fills and lifts north this afternoon and evening. VFR cu
should persist through the day, outside of KDUJ and KFKL where MVFR
cigs are expected today. Latest guidance has backed off on afternoon
convection, with best chances for precipitation holding off until
this evening. Have included Prob30s for the scattered showers, and
given timing, have removed TSRA mention for now.

Outlook...
Some patchy morning fog or stratus is possible early Thursday
morning with low level moisture in place. Showers and
thunderstorms are likely late Thursday night into Friday
morning, and again Friday afternoon and evening. Some of these
storms could be severe. Additional showers are possible with a
Saturday cold front. Mainly dry weather and VFR returns Sunday.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...Flood Watch until 10 PM EDT this evening for PAZ073>076.
OH...None.
WV...Flood Watch until 10 PM EDT this evening for WVZ510>514.

&&

$$

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