Tornado Warning 26, NWS Pittsburgh, PA

Area Forecast Discussion
National Weather Service Pittsburgh PA
150 PM EDT Thu Jun 25 2026

.WHAT HAS CHANGED...
Confidence in localized severe thunderstorms with large hail and
damaging wind gusts has increased for the northern 2/3rds of the
forecast area, and SPC has issued a SLGT risk of severe
thunderstorms accordingly for this afternoon and evening.

&&

.KEY MESSAGES...
1) Isolated strong to severe storms possible this afternoon and
evening.

2) A stalled boundary keeps rain chances in the forecast Friday
and Saturday, with some potential for isolated heavy rainfall
totals and instances of flooding.

3) High confidence in the development of hot and humid
conditions next week.

&&

.DISCUSSION...
KEY MESSAGE 1...
Mid-level troughing swings across the Great Lakes into the
northeast CONUS through tonight. Coincident with this, surface
low pressure tracks across Michigan towards the Saint Lawrence
River by 12Z Friday. This will push a surface boundary towards
the Upper Ohio VAlley by this evening. Lift will also be
supported by the left exit region of a 65 knot 500mb jet streak.
0-8km shear is in the 60-70 knot range creating long straight
hodographs that are favorable for splitting supercells with
large hail. There is broad model agreement on the development
of scattered to numerous showers and thunderstorms across Ohio
and far northwest Pennsylvania by mid- afternoon, with activity
spreading east and southeast through the late afternoon and
evening.

Shear in the 0-6km layer is certainly supportive of organized
convection, with HREF/REFS means of 40-50 knots during peak
heating. However, there are limiting factors that should temper
the severe weather threat somewhat. Surface dewpoints mainly in
the lower 60s are forecast, which will inhibit CAPE levels
somewhat. HREF probabilities of 1000 J/kg or greater are 30
percent or less across a good portion of the CWA, save for
potentially portions of far NW PA/eastern OH where buoyancy
could be a bit greater. MLCAPE of 500-1,000 j/kg along with the
shear support marginally severe hail up to 1.25 to 1.50". Low
level shear will be marginal for strong tornadoes, mainly in the
10-15 knot range during the daylight hours and increasing a bit
to 15-20 knots in the evening. Steep 0-3km lapse rates and
relatively high LCLs should limit tornado potential to 1 or 2
weak brief events at most.

DCAPE values of 500-800 j/kg are marginally supportive of
damaging winds, which would be more likely later in the event as
merging cold pools provide more concentrated wind threat.
What seems more certain is that heavy rain/flooding threats
will remain largely squashed by sufficient storm motion and non-
remarkable precipitable water values.

KEY MESSAGE 2...

As the front loses much of its upper support and becomes
parallel to quasi-zonal mid-level flow, much of its forward
speed will be lost, and it should eventually ooze to a nearly
stationary position either in or just south of the forecast
area, where it would likely remain through at least Saturday.
Additional shortwave energy should provide support for rounds of
showers and thunderstorms, especially Friday night and
Saturday, with best coverage generally south of US-422. Severe
weather risk from this activity appears relatively low given the
daytime heating issues this pattern could provide. However,
building precipitable water south of the boundary (1.7-1.8 inch
values eventually) and the potential for training thunderstorms
supports the notion of a risk for at least isolated flooding
issues across the southern CWA into Saturday. A marginal risk of
excessive rainfall covers much of the forecast area south of
I-80 for Friday and Friday night. By Sunday, the front may more
decisively nudge to our south, bringing an end to the heavy
rain threat.

KEY MESSAGE 3...
The boundary is set to lift back north of the region Monday.
There is broad model agreement on a strong 500mb upper high on
the order of 597 dm forming over the Ohio Valley in the vicinity
of southern Indiana. The main impact of this pattern is likely
to be the season's first sustained run of heat and humidity,
with the NBM indicating 70 percent or greater chance of 90+ high
temperatures over most of the non- ridge areas Tuesday through
Thursday. Accordingly, probabilistic Heat Risk guidance shows
70% or greater chance of Major (level 3 of 4) or higher impacts
over most of the CWA. We have deterministic Heat Indices in the
lowlands of 100 to 105 both Tuesday and Wednesday which are
representative. Looking at the NBM Wednesday July 1st 21z
Apparent Temperature percentiles, the 10th and 90th range from
93F-104F at KPIT, but for Downtown Pittsburgh the values are
100-115F. Those large spreads are typical and during heat waves
the daily cloud cover and thunderstorms chances also cause
uncertainty but the main message is hot and humid next week.

Secondary to the heat will be the eventual reintroduction of
some level of severe weather risk. Most likely, given the
abundant buoyancy potential and weak flow, this would come in
the form of typical mid-summer wet downburst wind threats.
There is a lower-end potential for a suppressed ridge by the end
of the week, which could create a upper level northwest flow
setup, a pattern which has been responsible for notable severe
weather events in the past. Of course, there is plenty of time
to monitor for that potential.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Continued broken to overcast VFR decks remain most likely
through the afternoon and overnight period in any area that is
not imminently experiencing a storm.

At the most recent update, timing for storms remain generally
unchanged. A brief prevailing group was added this afternoon in
the 18Z to 21Z window for storms at BVI, FKL, and DUJ, tracking
upstream development and an anticipated upward trend in
intensity. The main development window in eastern Ohio and
northwest PA around the 20Z to 22Z hour, with chances drawing
southeast, and ending for most by 04Z, save MGW were chances may
linger longer. Gusty and erratic winds remain possible in any
storm that might occur, with temporary MVFR/IFR restrictions.

Where it does rain today, the chances of low fog and low cigs
will increase overnight. Visibility restrictions are most likely
and denoted at only FKL/DUJ for now, where locally dense fog
will be possible.

Elsewhere, there a 75% chance of a MVFR deck for Friday morning
and a 25% chance of an IFR deck, with chances maximizing from
12Z to 18Z. Lifting is expected thereafter until restriction
chances increase overnight Friday.

Outlook...
Starting Friday night, an active pattern is favored through the
weekend featuring multiple rounds of showers and thunderstorms
within quasi-zonal flow.

&&

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

&&

DISCUSSION...Craven
AVIATION...Milcarek

Hazardous Weather Outlook
National Weather Service Pittsburgh PA
102 PM EDT Thu Jun 25 2026

OHZ039>041-048>050-057>059-068-PAZ007>009-013>016-020>022-029-073-
074-077-078-WVZ001>003-261200-
Tuscarawas-Carroll-Columbiana-Coshocton-Harrison-Jefferson OH-
Muskingum-Guernsey-Belmont-Noble-Mercer-Venango-Forest-Lawrence-
Butler-Clarion-Jefferson PA-Beaver-Allegheny-Armstrong-Washington-
Westmoreland-Higher Elevations of Westmoreland-Indiana-
Higher Elevations of Indiana-Hancock-Brooke-Ohio-
102 PM EDT Thu Jun 25 2026

This Hazardous Weather Outlook is for east central Ohio, western
Pennsylvania, and northern West Virginia.

.DAY ONE...This afternoon and tonight.

There is a slight risk of severe thunderstorms this afternoon and
evening with the threats for large hail and damaging wind gusts.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

There is a marginal risk of excessive rainfall for much of the area,
with the most likely area being along and south of I-70 Friday night
into Saturday.

Heat will begin to build in the lowlands by Tuesday and Wednesday
with Highs in the lower 90s and heat indices of 100 to 105 possible.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to Standard Operating Procedures.

OHZ069-PAZ031-075-076-WVZ004-012-021-509>514-261200-
Monroe-Greene-Fayette-Higher Elevations of Fayette-Marshall-Wetzel-
Marion-Monongalia-
Ridges of Eastern Monongalia and Northwestern Preston-Preston-
Eastern Preston-Western Tucker-Eastern Tucker-
102 PM EDT Thu Jun 25 2026

This Hazardous Weather Outlook is for east central Ohio, southwest
Pennsylvania, and northern West Virginia.

.DAY ONE...This afternoon and tonight.

While thunderstorms are possible tonight, the severe weather threat
is expected to remain north of the area.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

There is a marginal risk of excessive rainfall Friday night into
Saturday with local amounts of 2 to 3 inches and flash flooding
possible.

Heat will begin to build in the lowlands by Tuesday and Wednesday
with Highs in the lower 90s and heat indices of 100 to 105 possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

Craven

Special Weather Statement
National Weather Service Pittsburgh PA
1138 AM EDT Thu Jun 25 2026

OHZ041-PAZ007>009-013>016-020-022-251745-
Columbiana-Mercer-Venango-Forest-Lawrence-Butler-Clarion-
Jefferson PA-Beaver-Armstrong-
Including the cities of East Liverpool, Salem, Columbiana,
Sharon, Hermitage, Grove City, Oil City, Franklin, Tionesta,
New Castle, Ellwood City, Butler, Clarion, Punxsutawney,
Brookville, Aliquippa, Beaver Falls, Ambridge, Monaca,
Kittanning, and Ford City
1138 AM EDT Thu Jun 25 2026

While current showers moving through the area are not severe,
thunderstorms are expected to develop around 3 pm in the
Columbiana and New Castle areas and move along the I-80 corridor
into the Butler/Franklin areas around 4 pm and over to Clarion and
Punxsutawney by 5 to 6 pm. Large hail up to quarter to half
dollar size and damaging wind gusts are possible with these
storms. An isolated tornado can't be ruled out along with brief
torrential downpours.

OHZ039-040-048>050-057>059-WVZ001-002-251745-
Tuscarawas-Carroll-Coshocton-Harrison-Jefferson OH-Muskingum-
Guernsey-Belmont-Hancock-Brooke-
Including the cities of New Philadelphia, Dover, Carrollton,
Malvern, Coshocton, Cadiz, Steubenville, Zanesville, Cambridge,
Martins Ferry, St. Clairsville, Weirton, Follansbee,
and Wellsburg
1138 AM EDT Thu Jun 25 2026

Thunderstorms are expected to develop over central Ohio between 3
and 4 pm this afternoon and then move into east central Ohio by 5
to 7 pm. Large hail up to quarter to ping pong size and damaging
wind gusts are possible with these storms. An isolated tornado
can't be ruled out along with brief torrential downpours.

OHZ068-069-PAZ021-029-073-074-077-078-WVZ003-004-251745-
Noble-Monroe-Allegheny-Washington-Westmoreland-
Higher Elevations of Westmoreland-Indiana-
Higher Elevations of Indiana-Ohio-Marshall-
Including the cities of Caldwell, Woodsfield,
Pittsburgh Metro Area, Washington, Canonsburg, Murrysville,
Greensburg, New Kensington, Lower Burrell, Latrobe, Monessen,
Ligonier, Donegal, Indiana, Armagh, Wheeling, and Moundsville
1138 AM EDT Thu Jun 25 2026

Thunderstorms are expected to develop over central Ohio between 3
and 4 pm this afternoon and then move into southeast Ohio and
western Pennsylvania including the Pittsburgh area by 6 to 8 pm
this evening. Large hail up to quarter to half dollar size and
damaging wind gusts are possible with these storms.  An isolated tornado
can't be ruled out along with brief torrential downpours.

Craven