The EF Scale: How tornadoes are rated - KFVS12 News & Weather Cape Girardeau, Carbondale, Poplar Bluff

The EF Scale: How tornadoes are rated

(Source: Raycom Media) (Source: Raycom Media)
(KFVS) -

A "tornado" is a violent, rotating column of air extending from a thunderstorm to the ground.

Each year, the United States averages 1,000 tornadoes. That's a lot to keep up with.

Scientists saw the need to classify tornadoes in order to prevent or minimize future loss of life and property. 

In 1971, Dr. Ted Fujita created the "Fujita Scale," which estimated tornado wind speed on a scale from F0 to F5 according to the damage it produced.

Over the years, some weaknesses in the scale were found.

For instance, it overestimated wind speeds over F3 strength, and oversimplified damage descriptions.

In the early 1990s, a panel of meteorologists and engineers began to make adjustments and in 2007 released the "Enhanced Fujita" scale.

The changes made the scale more consistent in rating damage.

Characteristics such as building age, code, siting, and construction methods can affect the amount of damage caused by a tornado.

Half of all tornadoes are EF0 strength, and little or no damage is found with winds up to 85 miles per hour.

Winds up to 110 miles per hour produce EF1 damage—shattering glass, flipping mobile homes and uprooting trees.

The rarest of tornadoes is the EF5. Its 200 miles per hour wind utterly destroys everything in its path.

Tornadoes can spawn from severe thunderstorms in a matter of minutes, so it's important to know where you live on a map.

Also, you should be able to tell the difference between a tornado "watch" and "warning."

  • Tornado Watch – Conditions are favorable for tornadoes
  • Tornado Warning - A tornado has been sighted or indicated by radar.

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