Illinois has had more tornadoes over the past forty years and the trend is likely to continue.
That’s the conclusion of a new study that looks at the shifting location of the nation’s severe weather. The research shows more tornadoes east of the Mississippi River and a slight decrease in the historical “tornado alley” of the Great Plains and Texas.
“Over the past 40 years, Illinois has an increasing trend in both the reports and the environments that produce those reports,” said Victor Gensini, a professor of atmospheric science at Northern Illinois University and lead author of the report. “So it’s pretty consistent with what we’d expect to see.”
In addition to a shift in where property damage occurs, there’s a human element that comes into play when assessing the latest information.
“When you shift to the east, more people are likely to die,” Gensini said. “That was shown in a 2007 study. As these storms continue to move farther to the east, there’s more targets with a higher population density, but there’s also a lot more people living in poverty and mobile homes where they are very, very vulnerable to these types of events.”
Gensini is hesitant to offer an official explanation for the increase in tornadoes east of the Mississippi River.
“There’s a change, and the change is consistent with what some of the models have shown with the drying out of the Great Plains,” Gensini said. “It’s very hard in general to say that any given tornado is due to climate change. The short answer is it could be climate change, it could be natural variability, we just don’t know.”
The study looked at changes in patterns since 1979. Researchers examined the number of tornadoes reported, but also closely examined meteorological conditions that lead to severe weather breakouts.
“It’s important for things like setting insurance premiums and for FEMA targeting where we should be doing education and outreach,” Gensini said. “For example, if you’re in southern Illinois or Kentucky or Tennessee and the trend in your location is upward, then the trend across time is you’re more likely to be hit by one of these damaging events.”
Texas still has more tornadoes than any other state, but the four deadliest states for tornadoes are Alabama, Missouri, Tennessee and Arkansas.