Tornado Alley
Although the official boundaries of Tornado Alley are not clearly defined, its core extends from northern Texas, Oklahoma, Kansas, Nebraska, into South Dakota. States such as Missouri, Iowa, Minnesota, Wisconsin, Illinois, Indiana, and western Ohio are sometimes included in Tornado Alley. Some research suggests that tornadoes are becoming more frequent in the northern parts of Tornado Alley where it reaches the Canadian prairies.
Tornadoes in the United States
Florida is one of the most tornado prone states, with only Texas, Kansas and Oklahoma reporting more storms. During the period 1950 to 2006, Florida reported 2,884 tornadoes according to NCDC figures. However, Florida tornadoes are usually weak in comparison with those that strike the Plains and the Southern states – there have been only four reports of F4 strength tornadoes since 1950 and none of F5 strength. Florida experiences more thunderstorms than any other state but fewer supercell storms. Florida tornadoes are more often spawned by the frequent ordinary thunderstorms that occur over the state. Hurricanes and other tropical storms can generate large numbers of tornadoes. Non-supercell tornadoes are rarely as strong as supercell-generated storms.