Tornadoes start deep within vast thunderclouds, where a column of strongly rising warm air is set spinning by high winds streaming through the clouds's top. As air is sucked into this swirling column, or mesocyclone, it spins very fast, stretching thousands of feet up and down through the cloud, with a corkscrewing funnel descending from the cloud's base - the tornado.
What's the difference between a tornado and a hurricane? Find out . . .
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