Here's How Many Tornadoes Your State Sees In A Typical Year

Tornadoes can occur in any month of the year across the United States, and it should come as no surprise that the Plains states have the highest frequency of twisters in an average year.

NOAA's National Centers for Environmental Information (NCEI) compiled the 20-year annual average for every state based on data from 1991 to 2010. The NCEI data have been illustrated on the map below.

The number in each state depicts the average annual number of tornadoes, with various colors representing higher and lower averages.

States shaded in green in the Northeast and parts of the West each have five or fewer tornadoes in a typical year.

The yellow-shaded states in the mid-Atlantic, Great Lakes, Ohio Valley, mid-South, parts of the Southeast, as well as Montana, Wyoming, New Mexico and California, typically have between 10 and 30 tornadoes in an average year.

States shaded in orange in portions of the South, Mississippi Valley and Northern Plains have 31 to 45 tornadoes per year, on average.

The red-shaded states, including Florida, Illinois, Iowa, Nebraska, Oklahoma and Colorado, typically have between 51 and 66 tornadoes annually.

The two most active states for tornadoes are Texas, with 155, and Kansas, with 96, in an average year. They are both located in the heart of Tornado Alley, a nickname given to an area in the Plains between Central Texas and South Dakota that has some of the most tornadic activity in the world.

As a whole, the U.S. averaged 1,233 tornadoes annually from 2000 to 2019, 54% of which occurred between April and June.

When and Where the Most Tornadoes Typically Occur

Although strong tornadoes can occur in any month, weather history shows that April, May and June are the months with the highest potential of having both the greatest number of tornadoes and the most violent tornadoes in a given year.

May typically has the most tornadoes each year, with an average of 281. This is followed by June and April, which average 196 and 194 tornadoes per year, respectively.

(MORE: The Most Dangerous Three Months for Tornadoes in the U.S.)

Historically, the highest threat of tornadoes migrates from the South into parts of the Plains and Midwest as we advance through April, May and June.

For example, the potential for tornadoes in the South is much lower in June compared to April. Although moisture is abundant across the southern U.S. in late spring, the strong jet stream winds needed to make conditions favorable for tornadic thunderstorms move northward toward the Canadian border.

By summer, tornadoes can occur virtually anywhere nationwide because warmth and humidity are the most widespread of any time of the year.

A secondary peak in tornado activity occurs in the fall in the Gulf Coast states, some of which can be attributed to tropical storms and hurricanes. Tornadoes can sometimes spread northward to the Ohio Valley and southern Great Lakes in the fall.

From late fall through winter, the greatest chance of tornadoes moves back to the South with the warmest air and much of the moisture.

Click through the slideshow below to see where the average tornado risk area is during each month.

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