The summer-like trend will carry over from the weekend and last through midweek. We made it to 83° Saturday and 82° on Sunday, but the warmest day this week will arrive on Tuesday.
But the summer like weather will bring the threat for showers and storms in the early evening. A stalled boundary currently in central Illinois will lift across northern Illinois this afternoon, in response to an incoming low pressure in the plains. This brings a chance for rain and storms to ride along the front, combining with areas of energy and lift that ride along a ridge over the area. However, with the placement of the front, the best coverage in storms will be in Wisconsin and along the Wisconsin stateline but also south through Rockford. That area is also where there is an enhanced risk for strong to severe storms. A slight risk encompasses our far southern counties.
In storms later today, we're watching the threat for heavy rain, strong wind, and even potentially hail in this MCS system. Best timing would be from the late afternoon and early evening, or between 4pm-10pm.