A wavy and nearly stationary frontal boundary was in place near the Mason-Dixon Line.  Morning clouds hindered destabilization somewhat, but afternoon clearing and the arrival of a mesoscale low allowed storms to blossom during the afternoon and evening.  Although a few wind damage reports were received, flash flooding was the main focus of this event.  Hardest hit were Allegheny, Washington, and Westmoreland Counties in Pennsylvania.  Here, numerous reports of roadway flooding were received, along with a few instances of creek overflows and residential basement flooding.

Flash Flood in FAYETTE, PENNSYLVANIA
From 10-JUN-18 20:16:00 to 10-JUN-18 22:27:00 (EST-5)
Location: BOWEST JCT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Baldridge Avenue in South Connellsville was closed due to flooding.

Thunderstorm Wind in FAYETTE, PENNSYLVANIA
From 10-JUN-18 17:29:00 to 10-JUN-18 17:29:00 (EST-5)
Location: VANDERBILT
Magnitude: 50.00 EG
Property damage: 0.50K
Crop damage: 0.00K
Reported by: Public

Trees were reported to be blown down just south of Vanderbilt.

Thunderstorm Wind in FAYETTE, PENNSYLVANIA
From 10-JUN-18 17:33:00 to 10-JUN-18 17:33:00 (EST-5)
Location: LEISENRING
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Public

Power lines were blown down on Highland Street in Leisenring.

Flash Flood in WESTMORELAND, PENNSYLVANIA
From 10-JUN-18 18:15:00 to 10-JUN-18 22:27:00 (EST-5)
Location: GROTZTOWN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flooding was reported at 258 Sutersville Road in Grotztown.

Flash Flood in WESTMORELAND, PENNSYLVANIA
From 10-JUN-18 18:39:00 to 10-JUN-18 22:27:00 (EST-5)
Location: COLLINSBURG
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: State Official

Residential flooding was reported on 1st Avenue in Sutersville.

Flash Flood in WESTMORELAND, PENNSYLVANIA
From 10-JUN-18 18:46:00 to 10-JUN-18 22:27:00 (EST-5)
Location: LOWBER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: State Official

Flooding was reported on Lily and Daisy Streets, and at 184 Lowber Road in Lowber.

Flash Flood in WESTMORELAND, PENNSYLVANIA
From 10-JUN-18 19:35:00 to 10-JUN-18 22:27:00 (EST-5)
Location: MIDDLETOWN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Flooding was reported on Middletown Road.

Flash Flood in WESTMORELAND, PENNSYLVANIA
From 10-JUN-18 19:43:00 to 10-JUN-18 22:30:00 (EST-5)
Location: STONEVILLA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Multiple roads in Greensburg were reported to be closed due to flooding.  Portions of US Highway 119 were closed, and severe basement flooding was observed in multiple homes.

Flash Flood in WESTMORELAND, PENNSYLVANIA
From 10-JUN-18 20:00:00 to 10-JUN-18 22:27:00 (EST-5)
Location: LOWBER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Multiple homes were flooded in the village of Lowber, with some debris washed onto roads.

Flash Flood in FAYETTE, PENNSYLVANIA
From 10-JUN-18 16:20:00 to 10-JUN-18 23:00:00 (EST-5)
Location: VANDERBILT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flooding was reported on multiple roads in Dunbar Township.

Flash Flood in WESTMORELAND, PENNSYLVANIA
From 10-JUN-18 19:52:00 to 10-JUN-18 22:30:00 (EST-5)
Location: FIVE PTS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flooding was reported at the intersection of Route 819 and Trees Mills Road.

Flash Flood in WASHINGTON, PENNSYLVANIA
From 10-JUN-18 17:29:00 to 10-JUN-18 22:27:00 (EST-5)
Location: THOMAS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Several roads were reported to be flooded in Nottingham Township.

Flash Flood in WASHINGTON, PENNSYLVANIA
From 10-JUN-18 17:29:00 to 10-JUN-18 22:27:00 (EST-5)
Location: GASTONVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Several roads were reported to be flooded in Union Township.

Flash Flood in WASHINGTON, PENNSYLVANIA
From 10-JUN-18 18:29:00 to 10-JUN-18 22:27:00 (EST-5)
Location: GINGER HILL
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

A water rescue took place at the intersection of Mingo Creek Road and Little Mingo Road.

Flash Flood in WASHINGTON, PENNSYLVANIA
From 10-JUN-18 18:30:00 to 10-JUN-18 20:45:00 (EST-5)
Location: LINCOLN HILL
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

A motorist was reported to be trapped by flood waters at the intersection of West Chestnut Street and Franklin Farms Road.

Flash Flood in WASHINGTON, PENNSYLVANIA
From 10-JUN-18 18:39:00 to 10-JUN-18 22:27:00 (EST-5)
Location: FINLEYVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: State Official

A vehicle was reported to be stuck in flood waters at Airport Road and Rankintown Road.

Flash Flood in WASHINGTON, PENNSYLVANIA
From 10-JUN-18 18:48:00 to 10-JUN-18 20:45:00 (EST-5)
Location: WASHINGTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

State Route 18 was closed at South Main Street by flooding.

Flash Flood in WASHINGTON, PENNSYLVANIA
From 10-JUN-18 20:05:00 to 10-JUN-18 22:27:00 (EST-5)
Location: VAN VOORHIS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: State Official

A vehicle was reported to be stranded by flooding at the intersection of Pittsburgh Road and Hetherington Road.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 17:37:00 to 10-JUN-18 22:27:00 (EST-5)
Location: COCHRANS MILL
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Peters Creek was reported to be flooding at the intersection of Peters Creek Road and Gill  Hall Road in Jefferson Borough.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 17:38:00 to 10-JUN-18 22:27:00 (EST-5)
Location: LARGE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flooding was reported along Route 51 in Jefferson Hills.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 17:38:00 to 10-JUN-18 22:27:00 (EST-5)
Location: LARGE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flooding was reported at 1675 State Route 51 in Jefferson Hills.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 17:41:00 to 10-JUN-18 22:27:00 (EST-5)
Location: BOSTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flooding was reported at the intersection of Long Run Road and Cool Springs Road.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 17:43:00 to 10-JUN-18 22:27:00 (EST-5)
Location: ELIZABETH
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flooding was reported at the intersection of 6th Street and Burnett Street.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 18:38:00 to 10-JUN-18 20:45:00 (EST-5)
Location: BRENTWOOD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Becks Run Road was closed by flooding between Brownsville Road and Raven Street.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 19:09:00 to 10-JUN-18 20:45:00 (EST-5)
Location: CHALEANT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: State Official

Flooding was reported at the intersection of Thompson Run Road and Larimer Avenue.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 19:10:00 to 10-JUN-18 22:27:00 (EST-5)
Location: DRAVOSBURG
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Flooding was reported at Sandy Lake along Marc Arthur Drive.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 19:36:00 to 10-JUN-18 22:27:00 (EST-5)
Location: LINCOLN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

A creek was reported to be flooding Glenn Avenue in Port Vue.

Flash Flood in ALLEGHENY, PENNSYLVANIA
From 10-JUN-18 20:12:00 to 10-JUN-18 22:27:00 (EST-5)
Location: MC KEESPORT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: 911 Call Center

The intersection of Long Run Road and Rippel Road was reported to be flooded.