Strong to severe convective development shifted east of the Lake Erie region into northwest Pennsylvania, within a zone of broader vertical ascent extending downstream from an upper level wave migrating into the Great Lakes region. Isolated straight-line wind damage occurred around a supercell that moved across northern Warren into McKean County. Heavy thunderstorm rains also produced localized flooding and flash flooding.

Flash Flood in WARREN, PENNSYLVANIA
From 28-MAY-13 20:26:00 to 29-MAY-13 03:45:00 (EST-5)
Location: COLUMBUS
Flood cause: Heavy Rain
Property damage: 2.50K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy thunderstorm rains caused flash flooding and closed portions of US Route 6 in Columbus Township, SR 69 (Jackson Run Road) and SR 59 (Kinzua Road) in the northern part of the county. Warren Fire units were called for a water rescue on Brown Run Road as Brown Run came out of its banks and over-flowed the bridge. The flood waters also impacted one home on the south-side of Kinzua Road.

Flood in MCKEAN, PENNSYLVANIA
From 28-MAY-13 22:32:00 to 29-MAY-13 03:45:00 (EST-5)
Location: WEST BRANCH
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Heavy thunderstorm rains produced flooding across northwest McKean County. The flooding was primarily confined to rural areas, but a few secondary roads were closed around Bradford.

Thunderstorm Wind in WARREN, PENNSYLVANIA
From 28-MAY-13 20:41:00 to 28-MAY-13 20:41:00 (EST-5)
Location: RUSSELL
Magnitude: 50.00 EG
Property damage: 2.00K
Reported by: Social Media

Thunderstorm winds estimated near 60 mph knocked down trees along Route 62 near Russell.

Thunderstorm Wind in WARREN, PENNSYLVANIA
From 28-MAY-13 20:30:00 to 28-MAY-13 20:30:00 (EST-5)
Location: BEAR LAKE
Magnitude: 50.00 EG
Property damage: 2.00K
Reported by: 911 Call Center

Thunderstorm winds estimated near 60 mph knocked down trees along Swamp Road near the Pennsylvania-New York border.

Thunderstorm Wind in WARREN, PENNSYLVANIA
From 28-MAY-13 20:15:00 to 28-MAY-13 20:15:00 (EST-5)
Location: YOUNGSVILLE
Magnitude: 50.00 EG
Property damage: 2.50K
Reported by: Public

Thunderstorm winds estimated near 60 mph knocked down several trees near Youngsville.

Thunderstorm Wind in MCKEAN, PENNSYLVANIA
From 28-MAY-13 21:50:00 to 28-MAY-13 21:50:00 (EST-5)
Location: SOUTH BRADFORD
Magnitude: 50.00 EG
Property damage: 2.50K
Reported by: 911 Call Center

Thunderstorm winds estimated near 60 mph knocked down trees and utility wires on Dennis Lane near the Pitt-Bradford campus.

Thunderstorm Wind in WARREN, PENNSYLVANIA
From 28-MAY-13 20:40:00 to 28-MAY-13 20:40:00 (EST-5)
Location: NORTH WARREN
Magnitude: 50.00 EG
Property damage: 2.50K
Reported by: Social Media

Thunderstorm winds estimated near 60 mph knocked down trees and utility wires on Farm Colony Road near the Allegheny Forest Supervisor Office just off of Route 62 north of Warren.

Thunderstorm Wind in WARREN, PENNSYLVANIA
From 28-MAY-13 20:40:00 to 28-MAY-13 20:40:00 (EST-5)
Location: NORTH WARREN
Magnitude: 78.00 EG
Property damage: 10.00K
Reported by: NWS Storm Survey

NWS meteorologists determined that straight-line winds caused structural damage at a baseball field located just north of Backup Corners near Route 62 in Pine Grove Township. The bleachers, fencing and roof of the concession stand were damaged. A large building had its roof removed, a flag pole was bent, and a light pole was collapsed.