A Winter Weather Advisory has been issued for Winnebago, Boone, McHenry, Ogle, Lee and DeKalb counties until 4am Monday morning. Light snow has been moving across northwest Illinois Sunday evening, lifting into southern Wisconsin as low pressure moves across Iowa. Most of the snow will fall over Wisconsin, where accumulations of a couple inches are possible by morning.
Closer to the Stateline accumulations of up to an inch are possible, but mostly across far northwest Illinois from parts of Jo Daviess and Stephenson counties, and then into southwest Wisconsin. As this system lifts to the north, drier air in the middle part of the atmosphere may lead to the development of freezing drizzle during the night. The greatest impacts will be on untreated and elevated surfaces as those could become slick, as well as parking lots and sidewalks. You may also notice some ice on your cars in the morning if you left them outside. Temperatures will warm above freezing mid to late morning Tuesday, ending the threat for any frozen precipitation.