Southern Michigan is bracing for bitter cold and new waves of snow.

Tonight's low temperature in Detroit is expected to be 3 to minus 3, with a high tomorrow of 11 to 15. The National Weather Service expects one to three inches of new snow in the Detroit area tomorrow after more than an inch fell early today.

The service says the coldest air of the season has arrived in the Upper Peninsula and temperatures are expected to remain frigid for the rest of the week.

Thursday night's low could sink to 20 to 25 below zero.

Police in Grand Rapids have declared an extreme cold weather alert starting tomorrow. Police and fire crews plan to visit outdoor spots frequented by the homeless and ask them to come to a shelter for protection.