Tornadoes are measured on the EF Scale, which replaced the Fujita Scale in 2007. The scale measures wind speeds of tornadoes by looking at the damage caused on the ground after it has dissipated.

F5 tornado raked through two northern Illinois counties on the far southwestern edge of Chicagoland. The twister tore a ...

The Plainfield tornado touched down on Aug. 28, 1990, and remains the only F-5 tornado ever recorded in the state of Illinois. Even more staggering, it remains the strongest August tornado on record ...

Following tornadic storms Sunday in Denver, the National Weather Service will conduct storm surveys to determine their intensity and path length. The Enhanced Fujita scale is used to rate tornadoes.

For example, if a tornado rated before 2007 was an F5, the rating remains an F5, although its estimated wind speed may now be considered slightly lower than originally thought, according to the NWS.

The Enhanced Fujita Scale is a tornado rating that determines the wind speed by the damage the tornado produces but do we need to adjust it?

A massive tornado that tore through Lubbock on May 11, 1970, killed 26 people, left more than 500 injured, and caused $100 million in damages.

For example, if a tornado rated before 2007 was an F5, the rating remains an F5, although its estimated wind speed may now be considered slightly lower than originally thought, according to the NWS.

For example, if a tornado rated before 2007 was an F5, the rating remains an F5, although its estimated wind speed may now be considered slightly lower than originally thought, according to the NWS.