Swimming in Superior: warmer, sooner

Swimmers may be able to remain in Lake Superior a few minutes longer and perhaps earlier than usual this year – that, according to a report in today’s Minneapolis StarTribune.

The lake, often numbingly cold even in midsummer, is running warm this spring after a warm winter and lack of ice cover, said Jay Austin, a University of Minnesota Duluth lake researcher. Surface water that would usually have frozen never got colder than about 35.6 degrees during the winter, he said, and relatively warm water remained unusually close to the surface without losing much heat.

Now, the lake's summer "turnover," in which the warm water from below replaces cooler surface water, may occur in early June instead of the customary early July. Austin said, "It's going to be a great year for swimming.”