Terrifying twisters and severe storms were reported in Tennessee, Missouri, Arkansas, Indiana, Iowa and Kentucky.
One area hit very hard was Fairview, Ill., where a department store wall collapsed, killing a 54-year-old man.
Tom Lewis was just leaving the K & G store as the storm approached.
"It looked pretty ominous outside," he
"As soon as we got inside, the windows started to shimmer, to shake, and that's when I yelled at my wife and son and everybody in the store to get back to the back of the building, because I was afraid a tornado was coming. It was pretty scary at that point."
Lewis says it was business as usual in the store "until I started yelling, and then everybody else was yelling, you know, to get back to the back of the store, and it was pretty much mayhem at that point.
"And so we got back to the back of the building, and by the time we reached the rear of the building, that's when the wall collapsed, right where the cash registers are.
"When I saw the wall crash, it got really scary but, right after that, the roar went away, and I knew that it had hit and gone."
Lewis, whose wife was slightly injured added, "I've seen tornadoes before, but I've never been in destruction like this.
"(The 'wall cloud') was very distinct. Once you see one, you'll know it the next time. It's just a big rolling mass of cloud, and it's really green behind it, usually carrying hail and rain. And it brings a lot of wind."