Precipitation will begin to develop across parts of south central Illinois this afternoon as much colder air continues to filter in from the northwest. Initially, the precipitation will start out as a mix of rain and sleet, and then gradually transition to snow tonight with a period of freezing rain and sleet possible along and south of the I70 corridor. The snow will continue through most of the day Friday before ending by evening. Total accumulations are expected to range from 4 to 7 inches roughly along and south of I70, with the amounts diminishing quickly as you head north. Cold weather will continue this weekend and into next week with daytime highs mostly in the 20s, and early morning lows in the single digits and teens.