Big, strong, violent tornadoes don't happen that often around here. That all changed on May 31, 1985. At the time, the National Severe Storms Forecast Center noted that the atmosphere was ready for an explosive day. An unprecedented 44 tornadoes ripped across Pennsylvania, Ohio, New York, and Ontario, Canada. Nine of those twisters right in our backyard ranging from F-zeros to *** violent F5. This outbreak produced Pennsylvania's first and only F5 tornado. The violent twister coming out of eastern Ohio, crossing into PA near the community of Wheatland and Mercer County with estimated winds over 300 MPH. Damage continued for *** few more miles into the town of Mercer. Homes were blown clear off the foundation. Trucking plant twisted in the borough of just 1100 people. 6 people were killed, more than 40 homes demolished, and over 95% of Wheatland's trucking and steel industries were destroyed. Another strong tornado carved *** nearly 40 mile track across Beaver and Butler counties. Big Beaver was especially hit hard. Former WTAE chief meteorologist Joe Donardo recounts the aftermath. The following day we got in our helicopter and we flew the track of one of those tornadoes that went through Beaver County and the shopping center there one side of the street. There were no problems at all. Homes were standing. Directly on the other side of the street, homes totally demolished. This is the very same spot that Joe Denardo and Sky4 flew over almost 40 years ago to the day. The shopping center, it's been rebuilt *** little smaller these days with brand new tenants. The tornado actually then crossed the Beaver River and continued destruction in parts of Butler County. The severe damage across seven western Pennsylvania counties reminding meteorologists at the time of images from Tornado Alley. These tornadoes were not only strong, deadly, and destructive, but were on the ground for *** long time. *** F-4 tracked 56 miles across Mercer, Venango, and Forest counties. 65 Pennsylvanians lost their lives, making this the Keystone State's deadliest tornado day. The tragic twisters destroyed more than 1000 homes. There's not been *** day like it since. The damage from that day was inconceivable, and it really changed our area's perspective on strong and violent tornadoes. In NOAA's survey of this event, it said that perhaps the biggest lesson learned was under proper atmospheric conditions, major tornadoes can occur irrespective of location or terrain, end quote. Reporting in Big Beaver, Beaver County, Jill Swed, Pittsburgh's action weather.