Tornado Alley States 2020
Tornado Alley is the name commonly use for the corridor-shaped region in the United States Midwest that sees the most tornado activity. While it is not an official designation, states most commonly included are Texas, Oklahoma, Kansas, Nebraska, Missouri, Iowa, and South Dakota.
Florida, while not geographically part of tornado alley, sees more tornados than any other state, especially when accounting for how large the state is. The following list, reported by the National Climatic Data Center shows the seventeen U.S. states with the highest average number of tornadoes per 10,000 sq. miles each year. Figures are for the years 1991 through 2010.
The average tornado only stays on ground for 5 minutes, and approximately 77% are considered between EF-0 and EF-1, with about 95% below EF-3. Only .01% of tornadoes reach the highest category of EF-5. Even so, they can cause many fatalities and significant property damage.
With information available as recently as 2013, tornadoes cause an average of 94-110 fatalities per year, depending on the source of data. Property damage caused by tornadoes is incredibly difficult to calculate, and as such, little current information about damages per state exists.
The best estimation we have about property damage is from insurance claims, and it is still unclear how much damage was caused by tornadoes rather than coterminous weather. On average, tornadoes cause about $6.5 billion in damages across the entire U.S., with peak years reaching close to $14.5 billion in damages. That average is increasing as tornadoes are incurring with increasing frequency each year.
The best information available on a per-state basis is twenty-five years old, the data can be extrapolated over the last two decades as tornado occurrences have increased.
DEFINITION: Total cost of damage from tornadoes during the period 1950 to 1994, in adjusted US dollars.