It's been 40 years since western Pennsylvania endured one of the worst tornado outbreaks ever to hit the area.

Keystone State, including the first and only F5. This WTAE archive video shows some of the widespread damage in Pennsylvania.

It was "one of rarest" tornado outbreaks on record, says a tornado expert, but "things like that are possible." ...

The outbreak produced Pennsylvania's first and only F5 tornado, a violent twister that came out of eastern Ohio and crossed ...

A warm spring day turned to terror for residents of Pennsylvania, Ohio and southern Ontario 40 years ago this weekend.

Timeline: Hurricane Milton's tornado outbreak in Palm Beaches, Treasure Coast ...