ibex94, Michigan has frequent tornadoes in the spring and summer months. Global warming? Who knows. I remember them as a child and my hometown, Kalamazoo, had a humdinger in 1980 that changed the face of our downtown for ever. Massive loss of historic trees and some buildings.
Our tornadoes seem different from those I see in "Tornado Alley", Oklahoma, Texas etc. Because we are not flat but filled with hills, valleys, rivers and lakes our tornadoes seem rather wet and usually short lived. Tree damage is often the biggest problem. So many trees go down and they cause much of the damage after the tornado itself. We have about 20 per year most in what would be the cuff of the Michigan mitten.