Instability was able to build ahead of a cold front on May 26th.  CAPE values of 1500 to 2000 J/kg were achieved by afternoon, with sufficient wind shear and frontal support for lines of strong to severe thunderstorms.  Although a few reports of penny to quarter-sized hail were received, wind damage was the primary impact. Many reports of downed trees were received, causing scattered power outages and blocked roads.  A few reports of damage to cars and structures were received, with a patio roof blown off in Greensburg.

Thunderstorm Wind in WASHINGTON, PENNSYLVANIA
From 26-MAY-21 15:26:00 to 26-MAY-21 15:26:00 (EST-5)
Location: CANONSBURG
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Trees were reported to be blown down.

Thunderstorm Wind in ALLEGHENY, PENNSYLVANIA
From 26-MAY-21 16:08:00 to 26-MAY-21 16:08:00 (EST-5)
Location: MT LEBANON
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Multiple reports of trees and wires blown down were received from Mount Lebanon.

Thunderstorm Wind in WASHINGTON, PENNSYLVANIA
From 26-MAY-21 16:08:00 to 26-MAY-21 16:08:00 (EST-5)
Location: MC MURRAY
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Social Media

Pictures confirmed tree damage, with large branches blown down in McMurray.

Thunderstorm Wind in ALLEGHENY, PENNSYLVANIA
From 26-MAY-21 16:15:00 to 26-MAY-21 16:15:00 (EST-5)
Location: MUNHALL
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Several reports of trees down were received from in and near Munhall.

Thunderstorm Wind in ALLEGHENY, PENNSYLVANIA
From 26-MAY-21 16:15:00 to 26-MAY-21 16:15:00 (EST-5)
Location: OPTION
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Several reports of trees down were received from across the city of Pittsburgh.

Thunderstorm Wind in WESTMORELAND, PENNSYLVANIA
From 26-MAY-21 16:32:00 to 26-MAY-21 16:32:00 (EST-5)
Location: MARK ACRES
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: 911 Call Center

A tree was reported to be blown down on Government Road, blocking traffic.

Thunderstorm Wind in WESTMORELAND, PENNSYLVANIA
From 26-MAY-21 16:46:00 to 26-MAY-21 16:46:00 (EST-5)
Location: GREENSBURG
Magnitude: 50.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Public

Trees and power lines were reported to be blown down in Greensburg, along with a blown off roof.

Thunderstorm Wind in WESTMORELAND, PENNSYLVANIA
From 26-MAY-21 16:34:00 to 26-MAY-21 16:34:00 (EST-5)
Location: PLEASANT VLY
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: 911 Call Center

A tree was reported to be blown down and blocking Wedgewood Drive.

Thunderstorm Wind in WESTMORELAND, PENNSYLVANIA
From 26-MAY-21 16:48:00 to 26-MAY-21 16:48:00 (EST-5)
Location: STONEVILLA
Magnitude: 50.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Multiple reports of trees and wires down, blocking roadway, were received from Hempfield Township.

Thunderstorm Wind in WESTMORELAND, PENNSYLVANIA
From 26-MAY-21 17:03:00 to 26-MAY-21 17:03:00 (EST-5)
Location: BRADENVILLE
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Trees and wires were blown down, blocking Sunview Circle in Derry Township.

Thunderstorm Wind in WESTMORELAND, PENNSYLVANIA
From 26-MAY-21 17:20:00 to 26-MAY-21 17:20:00 (EST-5)
Location: NEW FLORENCE
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Social Media

A report of several snapped trees and downed branches was received.

Thunderstorm Wind in WESTMORELAND, PENNSYLVANIA
From 26-MAY-21 16:37:00 to 26-MAY-21 16:37:00 (EST-5)
Location: NEWTONSBURG
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: State Official

Multiple reports of trees and wires blown down and blocking roads were received from Newtonsburg.

Hail in JEFFERSON, PENNSYLVANIA
From 26-MAY-21 12:19:00 to 26-MAY-21 12:19:00 (EST-5)
Location: LANES MILLS
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in JEFFERSON, PENNSYLVANIA
From 26-MAY-21 12:19:00 to 26-MAY-21 12:19:00 (EST-5)
Location: LANES MILLS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in JEFFERSON, PENNSYLVANIA
From 26-MAY-21 12:20:00 to 26-MAY-21 12:20:00 (EST-5)
Location: LANES MILLS
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in WESTMORELAND, PENNSYLVANIA
From 26-MAY-21 11:40:00 to 26-MAY-21 11:40:00 (EST-5)
Location: NEW FLORENCE
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

The local fire department was dispatched to nine incidents of trees and large branches being blown down.  One large downed tree partially closed Route 711 in New Florence.
A large branch was also blown on to a house on 15th Street, and another large branch landed on a house and car on Vine Street.

Thunderstorm Wind in MERCER, PENNSYLVANIA
From 26-MAY-21 13:36:00 to 26-MAY-21 13:36:00 (EST-5)
Location: FARRELL
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Trees and wires were reported to be blown down.