Last night I told you about the Fujita-scale, which is used to rank tornado intensity. The scale goes from 0 to 5, with 5 being the strongest. We’ve never recorded an F4 or F5 around here, but there have been a few F3’s. One of the most recent occurred on this date back in 1994, in Chester County, PA.

That tornado touched down around 11pm. It was on the ground for about 4 miles with a path as wide as a football field. Eleven people were injured and property damage was several million dollars.

Though this tornado was rated F3, only a very small percentage of the area affected by the tornado actually received F3 damage. You see, a tornado’s F-scale rating is assigned based on the WORST damage done by the tornado. Even in a typical F5, less than 1% of the area in the path of the tornado actually gets F5 damage.