Will Lake Michigan Freeze Over?January 20th, 2009 at 5:09 am by Bill Steffen under Bill's Blog, Weather
This is a map of Great Lakes ice cover on Feb. 19, 1979. Satellite pictures can now give us a good idea of how much ice is on Lake Michigan, at least on those rare days when it’s clear. This is the MODIS satellite picture from Monday PM. Before satellites we can only guess as to whether Lake Michigan was ever solidly frozen over. Even in 1979, I had pilots tell me that they could always see some open water. In an average year, the ice on Lake Michigan only reaches a maximum of about 40%. Much of that is shoreline ice, plus Green Bay, Traverse Bay and the stretch from Beaver Is. to the Mac. Bridge. 1977 and 1994 also saw significant ice on Lake Michigan. The maximum ice cover in On the other hand, 1998 was just shy of 15%. Lake Erie is the Great Lake farthest south, yet it’s also the Great Lake that usually gets the highest percentage of ice cover. That’s because Lakie Erie is the shallowest of the Great Lakes, with an average depth of 62 feet and a greatest depth of 210 feet. Lake Michigan averages 279 feet deep, with a maximum depth of 925 feet. Lake Erie is freezing up now. When it does freeze up, you turn off the lake-effect snow from that lake, and you’d see a bit more sunshine. Also, the cold Arctic air would see very little modification crossing a mostly frozen lake. The cold nights with Arctic air and light winds will help create ice on the lakes. There is a lot of shore ice now, it’s getting hard to see open water from the Michigan shore. It’s only Jan. 20, so we may have four weeks to work toward maximum ice, which should bring us to one of the stellar years for Great Lakes ice if this weather pattern continues.