The original “Fujita” scale was developed and published by Dr. Theodore Fujita in 1971. In 2007 the National Weather Service updated the scale terming it the Enhanced Fujita Scale.
Since the original scale was developed before computers were widely used the National Weather Service decided to update and standardize the scale.
The most important thing to remember is that this is a DAMAGE scale and it is surveyed as assessed after the tornado has hit an area. Usually the next day, National Weather Service crews look at the damage and compare it to standardized photos and construction standards to estimate the damage the winds have caused in an area.
|EF Rating||3 Second Gust (mph)|