| A localized and violently destructive wind storm occurring over land and characterized by a funnel-shaped cloud extending towards the ground. A tornado is a violently rotating column of air in contact with and extending between a convective cloud and the surface of the earth. It is the most destructive of all storm-related atmospheric phenomena. They can occur anywhere in the world given the right conditions, but are most frequent in the United States in an area bounded by the Rockies on the west and the Appalachians in the east. |