Snow and colder will be the weather picture for this weekend. The snow will start by this afternoon with most of the accumulations tonight . The snow will decrease from the west late tonight and Sunday. Northwest Iowa has the greatest snow potential of 4 to 8 inches. Lesser amounts are expected to the north, with 1 to 3 inches from Huron to Brookings South Dakota and Marshall Minnesota. Northerly winds will cause some drifting snow, and wind chills will drop below zero as colder air arrives.