Travel Monday along and around the south end of Lake Michigan into northwest Indiana will become hazardous, as roads become snow-covered and slick, due to heavy lake-effect snows complicated by some blowing and drifting. See the pictorial below prepared by the Chicago National Weather Service.
Two to 6-inches-plus heavy snows are likely Monday into Tuesday around the south end of Lake Michigan into Northwest Indiana. Lesser amount are expected along and just inland of the Cook County Lake Michigan shoreline with the higher-end 6-inch totals most likely occurring farther east as you cross Lake and Porter Indiana Counties into St. Joseph, La Porte, Starke and Marshall Counties. Hazardous travel will also extend north into Berrien County, Michigan.
Gale warnings will be up on Lake Michigan Monday/Monday night and the north winds gusting over 40 mph will build 5 to 10-foot waves along the Illinois Lake Michigan Shoreline and 10 to 15-foot waves along the Indiana Lake Michigan shoreline resulting in extensive Lakeshore flooding.
Low pressure will deepen as it moves north along the Appalachian Mountains developing strong northerly winds on the backside of the strengthening system. Widespread rains are expected along the eastern seaboard with heavy snows expected over portions of Ohio, West Virginia, and Pennsylvania.