Extreme weather: Tornado
Where it takes place: Most tornadoes are found in the Great Plains of the central United States which is an ideal environment for the formation of severe thunderstorms. In this area, known as Tornado Alley, storms are caused when dry cold air moving south from Canada meets warm moist air traveling north from the Gulf of Mexico.
How it affects people: Besides causing loss of life, tornadoes move buildings, pluck trees from the Earth and send anything not anchored to the ground flying through the air. Most of the people who live where tornadoes occur regularly have underground shelters to keep them protected as they ride out the storm.
