Tornado seasons are the result of wind and weather patterns. During spring, warm air moves north and mixes with cold air remaining from winter. In autumn, the opposite happens. Cold weather moves south and combines with the last of the warm air from summer.
Tornadoes can strike with little or no warning. Most injuries happen when flying objects hit people. Experts say the best place to be is in an underground shelter, or a small, windowless room in the lowest part of a building.
People driving during a tornado are advised to find low ground and lay flat, facedown, with their hands covering their head. People in the path of a tornado often just have minutes to make life-or-death decisions.
The deadliest American tornado on record was the Tri-State Tornado of March 18, 1925. It tore across Missouri, Illinois and Indiana. Six hundred ninety-five people were killed.
Between March and May of 2011, there were 1,159 confirmed tornadoes across the United States. Scientists say that is the most on record for any three-month period. The most active month was April 2011, when 758 tornadoes were confirmed. That is the most ever for any month.
That April, the country broke a 37 year old record for the largest tornado outbreak. A “tornado outbreak” is commonly defined as six or more tornadoes produced by the same weather system within a day.
Scientists say the 199 tornadoes on April 27, 2011, were the most for any single day. They say the storms killed 316 people – the most ever in modern records for a 24 hour period.
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25