How to Measure Tornadoes: The EF Scale

The EF Scale


Tornado outside of Erie Kansas

Amy Price

The EF Scale (below) is the standard way to measure tornadoes based on wind damage.

The original Fujita Scale (or F Scale) was developed by Dr. Theodore Fujita. All tornadoes, and other severe local windstorms, were assigned a number according to the most intense damage caused by the storm.

The enhanced F Scale (EF Scale) was implemented in the United States on February 1, 2007. The EF scale uses three-second wind gust estimates based on a more detailed system for assessing damage, taking into account different building materials.

Note: Click on the chart below to enlarge.


The 2009 Old Farmer's Almanac

Reader Comments

Leave a Comment


this was not helpful

this is helpful

This is helpful to me because you are probably not understanding it as much as I am so ask for help.