A weak upper-level disturbance will pass over the Chicago area Sunday morning, spreading some accumulating light snow over the region, creating some minor accumulation and slick spots slowing travel and making for snow covered slippery slick streets and sidewalks. For the most part less than an inch is expected, although closer to two-inches could fall in counties farther north along the Illinois-Wisconsin border. The Chicago National Weather Service has prepared a nice pictorial below on amounts expected between mainly 5AM and noon.
A major storm system seems more and more likely to move out of the Texas panhandle Monday, tracking northeast, passing to our south through southern Illinois Monday night. There will likely be a Winter Storm Watch issued here before long, if the low pressure continues to develop. We could end up with snow accumulations of 6-inches or more later Monday/Monday night into Tuesday north of Interstate-80 and a wintry mix to the south. A preliminary National Weather Service pictorial is shown below.