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Tornadoes are swirling in unusual places. Why twisters are shifting east.

Tornadoes are touching down across the United States in seemingly unusual places, from Virginia to Michigan. On Sunday, tornadoes damaged buildings in Indiana, and forecasters see a risk of more this week linked to the expected Hurricane Helene in the Southeast.

But these events outside Tornado Alley – the Great Plains region known for its massive, slow-moving twisters – might not be as atypical as they seem. 

Why We Wrote This

Research suggests tornado patterns in the United States are changing, as twisters arrive later in the year and land farther east. We explore factors behind the trend and what residents can do to be ready.

Researchers suggest that the shift might represent a larger trend, with a recent study finding that the number of tornadoes is decreasing in the Great Plains while increasing elsewhere in the Midwest and in the Southeast.

The timing has also changed. Tornadoes outside the Great Plains tend to occur in the fall and winter, rather than in the summer. So that means that the eastward trend in the most tornado-prone regions of the U.S. is also accompanied by a shift in the season in which tornadoes are occurring.

The cause of the shift is difficult to pinpoint, and could be related to climate change or oscillations in the ocean, says Tim Coleman, director of forensic meteorology at WeatherBell Analytics.

Tornadoes are touching down across the United States in seemingly unusual places, from Virginia to Michigan. On Sunday, tornadoes damaged buildings in Indiana, and forecasters see a risk of more this week linked to the expected Hurricane Helene in the Southeast.

But these events outside Tornado Alley – the Great Plains region known for its massive, slow-moving twisters – might not be as atypical as they seem. 

Researchers suggest that the shift might represent a larger trend, with a recent study finding that the number of tornadoes is decreasing in the Great Plains while increasing elsewhere in the Midwest and in the Southeast.

Why We Wrote This

Research suggests tornado patterns in the United States are changing, as twisters arrive later in the year and land farther east. We explore factors behind the trend and what residents can do to be ready.

Why are tornadoes moving east?

The cause of the shift is difficult to pinpoint, says Tim Coleman, director of forensic meteorology at WeatherBell Analytics and lead author of a study on shifts in tornado activity published in June in the Journal of Applied Meteorology and Climatology. 

“It could be related to climate change,” he says. “We don’t prove or disprove that. It could also be related to these regular multidecadal oscillations in the ocean, and it could be something else. We don’t know.”

Grady Dixon, a meteorologist and climatologist, says climate change might be behind the geographical shift. He notes that the shift in tornadoes has been coupled with fewer tornado days but more tornadoes on each day. “That pattern of ‘fewer but bigger’ events seems to be common in other climate change-fueled weather patterns,” says Dr. Dixon, also a professor at Fort Hays State University in Hays, Kansas. “It fits the model.”

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