Short term thaw: Temperatures will continue to be above freezing through midnight tonight ahead of a weather system which will bring moderately colder air overnight as rain will slowly changing into snow. Temperatures will dive into the lower 30s as highs Wednesday and stay that way for the remainder of the week.
The Weekend: Another interesting pattern setting up for the weekend as Saturday we will still be dealing with high pressure which moves to the east coast. The movement of this high will allow for a southerly air flow pattern to begin setting up for the weekend. You can see on this image that 850 mb temperatures are still fairly cold on Saturday morning.
Sunday morning your eyes should be drawn to two things one is the large scale low pressure which is moving from the southern Rockies to the Plains. The second is the large red blob that indicates extremely cold air dumping into the northern Rockies. This is the core of the coldest air and has a temperature of -24 C! The big question here is when does this shift to the Great Lakes Region?
As the low moves across Wisconsin on Monday you can see that the cold expands into Minnesota and the Dakotas. Rain will change to snow and it looks like the cold air will be back here by next week.