Northwestern Wisconsin has experienced the area’s first widespread freeze, with overnight temperatures in the low 20s from International Falls to Hayward, covering the Boundary Waters, Voyageurs National Park, and the Apostle Islands region.. A Freeze Warning was active until 10 a.m. Wednesday morning, with subfreezing temperatures reported. The Canadian-driven cold snap ends the growing season, with expected freeze damage to agriculture in Ashland, Bayfield and Iron counties. In Michigan, freezing temps struck parts of Baraga, Gogebic, southern Houghton, and Ontonagon counties. Residents should put protection of plumbing and outdoor plants on the weekend to do list. Frost will remain along major highways, but skies will clear with warmer temperatures today, then leading to a chance of showers tonight, Friday and Friday night and Sunday.