Here’s where tornado activity is shifting across the U.S.

A new analysis reveals that tornado activity in the United States is shifting eastward and spreading across more months of the year, putting some Southern communities at greater risk. 

Tornado activity shifts eastward

Big picture view:

According to the analysis, published by the U.S. Census Bureau on Wednesday, the nation recorded approximately 1,559 tornadoes last year, about 27% above the 30-year average from 1991 to 2020.

During that period, tornado activity decreased by 25% in the West while increasing 12% in the East.

The analysis said that the shift is particularly concerning in parts of the South, where tornado activity is increasing and large numbers of residents live in manufactured homes.

The National Weather Service said people living in mobile homes are 15 to 20 times more likely to be killed in a tornado than those living in site-built housing.

In Greene County, Alabama, tornado events increased 171% from 2010 to 2025, and in St. Helena Parish, Louisiana, saw a 67% increase in tornado events during the same period. In Scott County, Mississippi, tornado events increased 12%.

Tornado season also expanding

Dig deeper:

But the changes aren't limited to geography, according to the analysis. Tornado activity is also spreading beyond the traditional late-spring-into-summer season.

Between 1950 and 2009, nearly two-thirds of U.S. tornadoes occurred between April and June. From 2010 to 2025, tornado activity increased during January through April, as well as in October and December.

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The South has seen some of the most pronounced changes, with Alabama, Louisiana and Mississippi experiencing tornado activity extending across seven months during the cooler parts of the year.

What They’re Saying: "This growing threat of near year-round tornadoes is most pronounced in the South, particularly the Gulf Coast states of Alabama, Louisiana and Mississippi, where moisture-rich air creates an uninterrupted, seven-month tornado season in the cooler months," the census wrote.

Tornadoes among costliest weather hazards

Tornadoes are also among the costliest weather hazards in the country. Since 1980, they have accounted for nearly half of all billion-dollar weather disasters, according to NOAA.

As tornado activity shifts geographically and extends into more months of the year, officials say accurate detection, warning systems and information about vulnerable communities will remain critical to helping people prepare.

Severe WeatherU.S.