FARIBAULT, Minn. - Several means exist to gauge the temperature of a lake.
"Comparable to my hot tub way turned down," says Chrissy Craig, as she watches her children from a lawn chair, dangling her feet in Cannon Lake.
T.J. DeBates method is more scientific. "Water temperatures right around, 80 to 81 degrees," announces the DNR fisheries supervisor from Waterville after upon dropping a water temperature monitor into the lake.
You know it's been warm when 80 degree lake water represents a cool-down. But on Cannon Lake that's exactly the case.
Earlier in July, the DNR was measuring water temperatures in southern Minnesota "pushing 90 degrees in some of our shallow lakes," according to DeBates. "This is probably the hottest weather I've seen since I've been with the DNR."
The results have been predictable: fish kills on 25 Lakes across 32 southern Minnesota counties. One of the largest kills occurred on Freeborn County's Lake Geneva, where thousands of fish, mostly northern pike, died.
In shallow lakes, DeBates explained, "they really have nowhere to go" to escape the oxygen-depleted warm water. "When it's warm like this, it's a very natural occurrence."
But it's not just southern lakes that are experiencing warmer than average temperatures. Recent readings on Lake Superior at Duluth have been 20 degrees above normal, the warmest surface temperatures in decades.
One bit of good of news: the Minnesota Pollution Control Agency confirms it's seen no more beach-closing algae blooms than usual this summer, possibly due to favorably-timed rains and brisk winds, breaking up the algae and doing swimmers a favor.
Of course it's only the end of July.
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