If you swam Superior late this summer you will have noticed the warm water temperatures. Infosuperior has heard reports from swimmers utilizing inshore areas deep in protected bays, also from swimmers who have enjoyed Superior’s waters at locations around the tips of the Black Bay and Sibley Peninsulas, which jut well out into Lake Superior on the Canadian side. Reports are all the same, surprisingly warm.
On the U.S. side of Superior at Park Point, on the open lake side of the long sand spit bordering Duluth’s inner harbour, temperatures remained at about 70 degrees F or 21 degrees C for weeks. In fact, the average temperature for the entire lake hit 21 degrees C or 68.5 in late August.
On a related note, small algae blooms have been noted in Lake Superior waters at Meyers Beach, just west of the Apostle Islands in Wisconsin. Examination of samples by microscope showed plenty of blue-green algae.
Superior seems to have exhibited two key themes over the summer, high water levels (about a foot above the long-term average) and warm water temperatures. Also, a major event for Superior was the massive storm which hit the south shore in mid-July. Many will have read of the storms incredible impacts at Saxon Harbour, on the Wisconsin/Michigan border. In addition to the major damage to roads, infrastructure boats and marinas, satellite photos taken after this major rain event showed a massive sediment plume extending well out into Superior, on a very long stretch of the south shore.
A Minnesota Public Radio article provides more information about this summer’s water temperatures, long-term temperature trends and how a given Lake Superior location can change from very warm, to very cold, in a matter of hours.
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