(Davenport, IA) — Illinois’ latest wind-chill advisory stretches from the northwestern tip of the state almost to St. Louis. The National Weather Service is leaving the advisory in place for the northern half of the state until at least 10 a.m. today. Forecasters say the wind chill will dip to as cold as 25 degrees below zero in some places. That’s cold enough to cause frostbite in as little as 30 minutes.