The Midwest is in for a warm, then chilly active week. Thunderstorms will move through areas in Wisconsin, Iowa and Illinois today and tomorrow, with severe weather possible. Tuesday looks to be the warmest day, with widespread 80s generally south and east of Minneapolis. Then as we head into Wednesday and mostly Thursday an area of upper level low pressure will separate itself from the jet stream and stick around well into the weekend. Notice in the video the circular isobars and abundant energy in the Midwest. Usually these storms are steered by the upper level patterns, but since it is a "closed low" and separate from the jet stream it will meander for days, with unsettled rain showers (some snow possible) and clouds.