Posted July 1, 2008, 6:32 AM.

The rating is preliminary, and is based on calculated winds of 110 to 120 mph. Dr. Kishor Mehta of Texas Tech Wind Engineering Lab and Tim Marshall, Wind Engineer and meteorologist agreed on the wind speed for the tornado, which was consistent with that needed to topple a railroad car.

The tornado was one of multiple spouts reported near Perris and Moreno Valley. This one overturned a truck on the Interstate 215 freeway and derailed railroad cars on adjacent railroad tracks.

The tornado began at 4:42pm May 22nd and ended near 5:03pm.

Other inland tornados in recent years have been rated F-1, including those that hit Temecula and Fallbrook in 2005.

The enhanced Fujita scale was put in place in 2007, replacing the original Fujita scale. The Perris tornado was the first in California to receive an EF-2 rating. The last tornado to receive a F-2 rating in California occurred in Sunnyvale on May 5, 1998.

Thanks to Jim Purpura of the National Weather Service for this report.