A cold front moved across the Ohio Valley and southern Great Lakes on the afternoon of Sunday, November 5th, 2017. Unseasonably warm and humid air was in place across the region ahead of the front. The cold front gradually progressed across the Ohio Valley and thunderstorms initiated and swept east ahead of the front. The storms formed in a very strong wind field and allowed the storms to move very rapidly east at speeds of 60 to 80 mph.  A tornado was reported near Erie and strong winds downed many trees across the area.

Thunderstorm Wind in CRAWFORD, PENNSYLVANIA
From 05-NOV-17 19:00:00 to 05-NOV-17 19:00:00 (EST-5)
Location: LINESVILLE
Magnitude: 50.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds downed several large trees.

Flash Flood in ERIE, PENNSYLVANIA
From 05-NOV-17 20:01:00 to 05-NOV-17 22:00:00 (EST-5)
Location: NORTH EAST
Flood cause: Heavy Rain
Property damage: 40.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Strong storms with torrential rainfall moved over portions of Erie County during the evening of the 5th. By 800 pm, reports came in of significant flooding in North East. Most of the downtown district had flood waters over a foot deep with numerous businesses and homes seeing flooding in their basements and about a half dozen with water in their first floor. The flooding was the result of torrential rainfall with rainfall rates estimated over 5 inches per hour.

Flash Flood in ERIE, PENNSYLVANIA
From 05-NOV-17 19:48:00 to 05-NOV-17 23:00:00 (EST-5)
Location: EAGLEHURST
Flood cause: Heavy Rain
Property damage: 270.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Warm humid air over the region supported strong thunderstorms and torrential rainfall. A rain gauge network in Mill Creek Township measured an instantaneous rainfall rate of over 7 inches per hour around 630 pm. The storms produced a measured 3.85 inches of rainfall  in the Erie/Mill Creek area. The intensity of the rainfall ultimately overwhelmed storm drainage systems causing significant overland flooding. In Mill Creek some roads were reported to have as much as five feet of water with numerous water rescues conducted. Some structures sustained damage and the Mill Creek Fire Department had to evacuate. The most significant damage occurred in on East 30th Street in Erie where a basement wall collapsed from the water pooling on the outside, trapping and ultimately drowning two residents. The flooding was likely exasperated by the poor drainage, but ultimately it was the torrential nature of the rainfall that caused the damages.

Thunderstorm Wind in ERIE, PENNSYLVANIA
From 05-NOV-17 18:05:00 to 05-NOV-17 18:07:00 (EST-5)
Location: (ERI)ERIE INTL ARPT
Magnitude: 50.00 EG
Property damage: 125.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm downburst winds downed trees and caused minor damage to homes in Millcreek Township.  Most of the damage was along and south of West 26th Street (U.S. Route 20) just to the southeast of Erie International Airport.

Tornado in ERIE, PENNSYLVANIA
From 05-NOV-17 18:07:00 to 05-NOV-17 18:09:00 (EST-5)
Location: WESTMINSTER
Tornado F-scale: EF0
Property damage: 500.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

An EF0 tornado touched down in Millcreek Township near the intersection of Butt Street and Sterrettania Road.  The tornado continued east northeast and damaged a few homes and a shopping plaza along Legion Road.  Most of the damage was from lost roofing.  Several trees were uprooted in the area as well.  The tornado strengthened to EF1 intensity as it approached Intestate 79.   Several businesses in the area sustained damage.  After crossing Interstate 79 the tornado traveled several more blocks and weakened to EF0 intensity. The tornado eventually lifted as it approached Greengarden Boulevard after being on the ground nearly two miles.  Dozens of trees were downed along the damage path.