In a typical winter, ice covers approximately 50 percent of the surface of Lake Michigan, but the lake has never completely frozen over. The lake does not freeze due to a vast reservoir of heat that is contained in the lake and the contrast of the wind and wave actions, according to the Great Lakes Environmental Research Lab.
Lake Michigan has a surface area of approximately 22,300 square miles, which makes it the third largest of the Great Lakes. It is also the only one of the Great Lakes that is located entirely in the United States.
Lake Michigan borders the states of Indiana, Illinois, Michigan and Wisconsin. Water temperatures vary from the 60s in July and August and can even reach the 70s if the area experiences temperatures in the 90s for several days. During winter large wave swells often occur that cause the shoreline temperatures to drop. While the lake has never been completely frozen over, it has been 90 percent frozen several times.
A place of many different habitats, the lake features sand dunes, marshes, tall-grass prairies, savannahs and even forests that can reach for hundreds of miles. The lake is also home to a variety of fish including crawfish, smallmouth bass, salmon, trout and walleye. Fisheries are prevalent in the region.