With the harsh winter behind us, things on the Great Lakes should be warming up for summer. But thanks in part to the harsh winter’s extensive ice cover, Lake Superior’s surface water temperature is predicted to be its lowest since 1979. 
 
“In a follow-up to evaporation studies funded by the Great Lakes Integrated Sciences and Assessments Center, a federally funded collaboration between U-M and Michigan State University, Lenters and his colleagues developed a map-based water-temperature forecasting tool called SLATE, which stands for Seasonal Lake Temperature Energetics model.
 
The experimental model was used to generate the Lake Superior forecast and may later be used to create similar surface-water temperature forecasts for all five Great Lakes—possibly even evaporation forecasts. SLATE is believed to be the first map-based forecasting tool that shows anticipated variations in surface-water temperature from place to place across one of the Great Lakes.
The Lake Superior forecast is expected to be of interest to swimmers, boaters, anglers and others who will be affected by chilly water temperatures not seen since perhaps as far back as 1979.
 
‘If you’re planning to go swimming in Lake Superior this summer, you should probably stay close to shore,’ said Peter Blanken, a co-investigator from the University of Colorado.
 
The U.S. Coast Guard in Marquette has already expressed interest in using the Lake Superior forecast to help plan summer search-and-rescue operations. And a long-distance swimmer who is planning a trek from Milwaukee to Chicago in Lake Michigan this summer has also asked about water temperature forecasts.”
Read more about the temperature forecast as well as predictions about Lake Superior’s water levels at the link above.

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Join the 2026 Great Lakes BioBlitz! 🌎🦋📸Starting Earth Day, educators, students, youth groups, and families are invited to help document biodiversity across the Great Lakes region using iNaturalist. A kick-off webinar is scheduled for April 16th at 2 pm CT.Participate anytime during the four‑week event. Snap photos, make observations, and contribute to real conservation data while getting students outside and engaged with nature. Learn more and get ready to explore: https://sites.google.com/wisc.edu/annual-great-lakes-bioblitz/2026 #TeachingTuesday#GreatLakes
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