Sloshing Lake Michigan

Cool.

Lake Michigan’s water levels may fluctuate by a foot or two this evening between Sheboygan and Winthrop Harbor, Ill., due to the displacement of water caused by a series of thunderstorms that passed from west to east across Lake Michigan today, according to a marine weather statement issued by the National Weather Service office in Sullivan.

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The storms pushed water to the east side of the lake, the statement says. The water began sloshing back toward the west side of the lake about 3:30 p.m.

Such water movement is known as a seiche (pronounced SAYSH), which is caused by strong, sustained winds that move water from one part of a lake to another.