Lake-effect Snow in the Great Lakes Region

During the late fall and winter seasons in the Great Lakes region, the flow of cold air masses across the relatively warm waters of the Great Lakes waters results in the production of dramatic lake-effect snowfall downwind of the lakes, particularly on the southern and eastern shores. This lake-effect produces increased seasonal snowfall amounts compared with communities farther inland, as well as located upwind of the Great Lakes. 

The Upper Peninsula of Michigan features one of the largest and most distinct snowbelts in the United States. Due to their large area and depth, the surface waters of Lake Superior, Lake Michigan, and Lake Huron freeze less completely. With open lake water throughout the winter months, lake-effect snow can fall continually across the Upper Peninsula and Canadian snowbelts. From the Porcupine Mountains and the Keweenaw Peninsula to Whitefish Point, snowfall is dramatically enhanced by lake effects. In some areas, annual snowfall totals commonly exceed 250 inches (635 cm) per year. The Keweenaw Peninsula, which averages more snowfall than any location in the United States east of the Mississippi River, owes much of its winter snowfall to lake effects. For comparison, Duluth, Minnesota, which lies outside the lake effect zone at the southwestern tip of Lake Superior, receives 78 inches (198 cm) per season.

Western Michigan, Northwestern Lower Michigan, and Northern Indiana can experience heavy lake-effect snow. As winds pass over Lake Michigan and generate snow, areas near Traverse City (MI), Muskegon (MI), Grand Rapids (MI), Kalamazoo (MI), South Bend (IN), and Elkhart (IN) can experience significant, often disruptive, lake-effect snowstorms. These snowfall events can reach far across Michigan and Indiana, but typically result in reduced snowfall totals before reaching areas such as Lansing (MI) and Fort Wayne (IN). When these cold winds flow across the short axis of a given lake (e.g., west to east across Lake Michigan), multiple effects of bands are predominant. In contrast, when these cold winds flow along the long axis of a given lake (e.g., north to south across Lake Michigan), a single band of lake-effect snow is often produced. Under cold northerly flow down the length of Lake Michigan, intense, but localized, lake-effect snowfall can be observed in Northwestern Indiana. 

The region east and southeast of Lake Ontario frequently sees daily snowfall totals that are higher than anywhere in the United States. Syracuse, New York, receives significant lake-effect snow from Lake Ontario, averaging 116 inches (294 cm) of snow per year. Lake Erie produces a lake effect zone stretching from the eastern suburbs of Cleveland, Ohio to Buffalo, New York. Due to its relatively shallow depths, Lake Erie has the distinction of being the only Great Lake capable of completely freezing over. As it freezes throughout the winter,  and the supply of moisture from the lake surface is cut off, lake-effect snow events cease.

Overall, snowfall has increased in northern lake-effect zones in the Great Lakes basin even as snowfall totals in Illinois, Indiana, and Ohio have declined with rising temperatures. Warmer Great Lakes surface water temperatures and declining Great Lakes ice cover have likely driven the observed increases in lake-effect snow. As global temperatures continue to rise and further warm the Great Lakes, areas in lake-effect zones will continue to see increasing lake-effect snowfall. ¹ Areas in more southern lake-effect zones may see lake-effect snow replaced by lake-effect rain, as winter temperatures will warm and be less suitable for snow.