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A weak tornado that was seen in Southeast Colorado.
Click on image for full size
Courtesy of University Corporation for Atmospheric Research, Photo by Linda Lusk

Sizes of Tornadoes

Tornadoes have three sizes. The size of the tornado shows how big the tornado is and how long it will live.

A weak tornado is the most common size of tornadoes. These tornadoes last for a very short time. The wind from this size of tornado is rather small compared to the other sizes. Weak tornadoes can cause minor damage.

Strong tornadoes are the middle of the size range for tornadoes. More people have died from strong tornadoes than from weak tornadoes. Strong tornadoes last for 20 minutes or longer. Strong tornadoes can rip trains of their track and turn them over.

Violent tornadoes do not happen very often, but they are very dangerous and deadly. A violent tornado can last longer than an hour. Winds from this size of tornado are very fast. The violent tornado destroys everything in its path.

Last modified June 11, 2008 by Vanessa Pearce.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA