India, April 28 -- Severe thunderstorms are expected to rumble over a large portion of the United States on Monday, with the Upper Midwest perhaps experiencing the worst devastation.

From northern Minnesota to southwest Texas, 36 million people are at risk of severe storms that could bring with them powerful tornadoes, hail and dangerous straight-line winds.

Monday is expected to see two rounds of storms: one that will move across Minnesota by midday, and another that is expected to occur by the afternoon and last into the evening.

Minnesota, Wisconsin, and northern Iowa are expected to be hit with a number of catastrophic storms.

The tornado risk is reliant upon the storm's composition and the amount of sunlight on Monday afternoon....