A tornado is a relatively small-diameter column of violently rotating air developed within a convective cloud that is in contact with the ground, usually in association with thunderstorms during spring and summer.

tornado

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Q: How long do tornadoes last?

The lifetime of a tornado is directly related to its intensity. The strong, intense tornadoes tend to last longer. Most tornadoes are weak, lasting only about two to three minutes on average. A typical lifetime for strong tornadoes is about eight minutes, while violent ones last about 25 minutes. In exceptional cases, violent events can last more than three hours.

Q: Where do tornadoes occur?

Tornadoes are most common on continents in the midlatitudes (between 20 and 60 degrees north and south), where they are frequently associated with thunderstorms that develop in regions where cold polar air meets warm tropical air.

Q: Which country has the most tornadoes?

In absolute numbers, the United States has the most tornadoes by far: more than 1,000 per year have been reported there every year since 1990. It also has the most violent tornadoes, about 10 to 20 per year.

Q: How fast are tornado winds?

Tornadoes can generate the strongest winds known on Earth: wind speeds in the range of 500 kilometres (300 miles) per hour have been measured in extreme events. When winds of this magnitude strike a populated area, they can cause vast destruction and great loss of life, mainly through injuries from flying debris and collapsing structures.

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Written by John Snow

Fact-checked by The Editors of Encyclopaedia Britannica

Last Updated: Aug 9, 2025 • Article History

Key People:: Tetsuya Fujita

Related Topics:: waterspout; How Do Tornadoes Form?; Why Does the United States Have More Tornadoes than Any Other Country?; tornado outbreak; mesocyclone

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What is a tornado?

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News •

On This Date: Brooklyn's First Tornado In Over A Century • Aug. 8, 2025, 3:55 AM ET (The Weather Channel)

'The whole house was shaking,' Huron County woman recalls close call with tornado • July 28, 2025, 6:38 AM ET (CBC)

tornado, a small-diameter column of violently rotating air developed within a convective cloud and in contact with the ground. Tornadoes occur most often in association with thunderstorms during the spring and summer in the mid-latitudes of both the Northern and Southern Hemispheres. These whirling atmospheric vortices can generate the strongest winds known on Earth: wind speeds in the range of 500 km (300 miles) per hour have been measured in extreme events. When winds of this magnitude strike a populated area, they can cause fantastic destruction and great loss of life, mainly through injuries from flying debris and collapsing structures. ...(100 of 8079 words)

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