Is Indiana seeing more tornadoes than in the past? The answer is complicated and nuanced

Yahoo

04-04-2025

As Hoosiers clean up from severe storms Wednesday that battered central Indiana, scientists studying the climate say the state is likely to see an increase in the number of tornado outbreaks in the future.
That prediction is based on research by the Midwestern Regional Climate Center based at Purdue University and the National Weather Service. Scientists with the two organizations reviewed published studies in an effort determine if there is a link between climate change and tornadoes — and what that could mean for Indiana.
Melissa Widhalm, regional climatologist and associate director of the climate center, said any possible relationship between tornadoes and a changing climate is complicated and not fully understood.
'The big takeaway (from our research) is, if you look at the historical tornado occurrences, there is a trend that tornado outbreaks are getting larger,' Widhalm said. 'We're seeing them with more frequency.'
The work by Widhalm and others found the number of large outbreaks — storm systems that spawn 16 or more EF1 and greater tornadoes — are increasing.
Before 1980 there were, on average, about three and a half days per year with 16 or more tornadoes, they found. But since 2000, that average has doubled to seven days per year. However, the number of days when at least one EF1 tornado forms has dropped.
The research Widhalm and others reviewed did not identify any definitive cause for these apparent trends.
'It's really difficult to say human influence is what is causing this,' Widhalm said. 'It makes logical sense that human influence would have some proportion of influence and some of it's probably natural. What that proportion is? We don't know, we're trying to figure that out.'
Scientists also are trying to determine if these trends are expected to continue in the future, but the research is complicated. Advances in computer systems are helping the researchers find answers, Widhalm said, but they're not quite there yet.
Gabe Filippelli, professor of Earth sciences at Indiana University, also said the Midwest could see more tornadoes on average, but there will still be years with very few spinning up — and any increases may or may not be due to the effects of climate change.
"I think climate change is obviously a huge, pressing societal problem," Filippelli said, "but I also want to get the science right, and the science is that we don't necessarily see more tornadoes from climate change, yet it is actually causing us here in the Midwest to have to buckle up a lot more."
One thing that is certain is the population of Indiana is growing and that means more Hoosiers could be vulnerable to tornadoes, Filippelli said.
Some of this growth is due to climate migration, where people are moving away from coastlines facing sea-level rise and moving into the Great Lakes region. Filippelli said Indiana has already seen growth from these climate migrants and as the effects of climate change worsen, the state is likely see more.
Indiana is in a part of the country affected by severe weather, and it is severe weather season now, Widhalm said, so it is important to stay aware of the forecast and have an emergency plan in place with time to prepare.
The National Weather Service has a preparedness guide for all types of severe weather including tornadoes. Here are some rules when a tornado is approaching or strikes:
Move to a basement of safe room
If there's no basement, find a windowless interior room or hallway
Leave mobile homes and find the closest sturdy building
If outside, get into a vehicle, buckle up and drive to a sturdy building
IndyStar's environmental reporting project is made possible through the generous support of the nonprofit Nina Mason Pulliam Charitable Trust.
Karl Schneider is an IndyStar environment reporter. You can reach him at [e-mail]. Follow him on BlueSky @karlstartswithk.bsky.social
This article originally appeared on Indianapolis Star: Indiana likely to see an increase in tornado outbreaks, researcher says