The most severe tornadoes can reach wind speeds of 320 kilometers an hour or more. The resulting paths of damage can be up to three kilometers wide, while the smallest widths are less than 10 meters. In some cases, the paths of damage can extend more than 480 kilometers.
With a tornado, bigger does not necessarily mean stronger. Large tornadoes can be weak. And some of the smallest tornadoes can be the most damaging. But no matter what the size, tornado winds are the strongest on Earth. Tornadoes can carry trees, cars and homes from one place to another. They can also destroy anything in their path.
Tornadoes have been observed on every continent except Antarctica. But experts say they are most commonly seen in the United States. On average, more than 1,000 are reported nationwide each year.
The National Oceanic and Atmospheric Administration keeps records of tornado sightings. It says tornadoes kill 70 people and injure 1,500 others nationwide in an average year.
Tornadoes are observed most often in the center of the United States, where the land is mostly flat. The area where the most violent tornadoes usually happen is known as “Tornado Alley.” This area extends from Texas to South Dakota between the Rocky Mountains and the Appalachians.
Tornadoes can happen any time of the year. But most happen from late winter to the middle of summer. In some areas, there is a second high season in autumn.
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25