Looks like you're classic June severe weather set up in Minnesota and Wisconsin. Discrete cells look to form in Minnesota in the afternoon hours, soon after the storms form they will merge with each other and head Southeast into Wisconsin as a Squall line. Instability looks to be around 4,500 J kg, with dew points in the upper 60s, winds 18k above the surface look to be around 40-50kts. Cloud cover should not be an issue tomorrow. So radiation will easily be able to reach the ground and heat up the Earth's atmosphere in that area. (edited)