The National Weather Service Forecast office in Chicago has issued a Winter Weather Advisory covering the entire Chicago area of northeast Illinois into the northwest corner of Indiana – calling for a total snowfall of 3 to 6 inches from 6AM CST to 6PM CST Monday.
A complex low pressure system is forecast to move east out of the Rockies across the central plains Sunday night and up the Ohio River Valley Monday. Accumulating Snow is expected to spread west to east across the Chicago area Monday forenoon – ending from west to east later in the afternoon. The precipitation could start out as a snow/sleet mix in far southern portions of the area, but turn quickly over to all snow.
Advisories for freezing rain/sleet and accumulating snow are up for central Illinois, while heavy snow Advisories/Warnings are in effect Monday for portions of North Dakota, Minnesota, Wisconsin, Iowa and Missouri, as shown on the National Watch/Warning map below. A wintry mix is expected over Indiana.