We really haven't had a whole lot of cold air around, but that is going to change in a little less than a week.
After snow Sunday, there are a couple more storm systems worth watching for next week. The first one arrives Tuesday afternoon and evening. Earlier in the week it appeared as if a cold front would combine with an area of low pressure moving up from the south, spreading rain into Northern Illinois and Southern Wisconsin. Forecast models are now suggesting the cold front on Tuesday comes through a little sooner pulling down very cold air aloft, but shifting the low from the south further to the southeast with the precipitation bypassing the Stateline. If that does in fact happen, we would likely end up dry Tuesday and Wednesday.
Following the cold front Wednesday and beyond temperatures are going to take a big tumble. Arctic air rushes down over the Plains and Midwest pushing high temperatures down into the 20's and overnight lows into the low teens. Surface winds will strengthen Thursday which could push wind chills during the day into the single digits and near zero degrees Thursday and Friday mornings.