https://www.cbsnews.com/news/tornado-all...oma-study/
The study, conducted by two severe weather researchers, Harold Brooks of NOAA's National Severe Storms Laboratory in Oklahoma and Dr. Victor Gensini of Northern Illinois University, noted "significant increasing trends (of tornadoes) in portions of Mississippi, Alabama, Arkansas, Missouri and Illinois."
The increased risk of disaster is due to a combination of a factors, but greater vulnerability is apparently the biggest.
In part, that vulnerability stems from the mid-South being more densely populated, meaning more people are exposed. In addition, there are more trees in the region and that, combined with wetter, "rain-wrapped" storms make the tornadoes harder to see.
I'm a little surprised by the states they mentioned. I was in Nashville this summer and they were talking there about them now being in the epicenter of tornado activity. If Illinois is at greater risk, Tennessee and Kentucky are too. And maybe Indiana.
I'm also not sure that some of these states have 'more dense' of a population than say north Texas which is part of the old 'Tornado Alley' but I guess they're talking more about Oklahoma, Nebraska and the Dakotas?