Interstate 65 remains closed Monday morning from State Road 26 in Lafayette to U.S. 30 in Merrillville.
An INDOT spokesman says plows have been able to remove snow from the interstate, but the roadway is very slick.
INDOT also closed U.S. 231 in Tippecanoe and White counties until further notice. The stretch from U.S. 52 in Montmorenci to Interstate 65 is impassable.
A spokesperson says snow plows are having a difficult time removing snow.