what is lake effect snow

Lake-effect snow is a weather phenomenon that occurs during cooler atmospheric conditions when a cold air mass moves across long expanses of warmer lake water. This phenomenon is common across the Great Lakes region during late fall and winter. When the cold air passes over the unfrozen and relatively warm waters of the Great Lakes, warmth and moisture are transferred into the lowest portion of the atmosphere. The air rises, clouds form, and narrow bands of intense snowfall are produced on the leeward (downwind) shores. The areas affected by lake-effect snow are called snowbelts. Wind direction and the physical geography of the land and water are important factors in determining which areas will receive lake-effect snow. Lake-effect snow can result in heavy snowfall rates, often leading to significant total snowfall in affected areas