Tom Novak of Novak Weather expects an "explosion of thunderstorms" as the evening progresses Monday in Minnesota. 

Large hail, damaging winds and isolated tornadoes are all possible. Novak is monitoring an area along and south of the Interstate 94 corridor for severe potential. 

"The threat is increasing since we have a subtle boundary overhead & winds are turning in our atmosphere," Novak said. "Plenty of energy for these storms to tap."

He said storms should explode between by 9 p.m.