Water evaporating off lakes can increase air humidity and encourage cloud formation and precipitation in areas near shorelines. As cold air moves over a water body such as a lake, it picks up moisture; then, when the clouds reach the shoreline, the air moves upwards in what is called the orographic effect. This, in turn, creates concentrated bands of precipitation that then release precipitation within relatively short distances of shorelines.

Some record snowfalls have been documented as a result of the lake effect. For example, on January 17, 1959, 51 inches (129.5 centimeters) of snow fell on Bennetts Bridge, New York, over a 16-hour period. Buffalo, New York, is infamous for being buried in snow because of its proximity to Lake Erie. The winter of 1976 to 1977, for instance, saw the city experience 30-foot snow drifts. Storms with 70-mile-(113-kilometer)-per-hour winds and bitter temperatures led to the deaths of 29 people that season.