Weeks of hot weather, scant precipitation, and low winds have pushed the water temps into near-record temps in four of the five Great Lakes. Lower Saginaw Bay is expected to reach 80F later this week.
NOAA is reporting that water temperature is running 6 to 10 degrees above normal, resulting in setting new records on lakes Michigan-Huron, Erie, and Ontario. The biggest surprise is Lake Superior with water temps near 70F along the western shore near Duluth, Ashland, and Ontonagon.
Lake Huron, Saginaw Bay Water Temperature Forecast
NOAA’s surface water temperature forecasts show the entire southern Lake Huron basin hovering around the upper 70’s. This makes for pleasant swimming but curbs its temperature moderation along the shore. Area temps along the Lake Huron shore can typically be around 10 degrees cooler than inland. The record surface temps will undoubtedly impact that moderating effect.
But Will It Mean Smelly Muck from Blue-Green Algae?
There is a concern that the record-setting Great Lakes water temps could lead to the growth of cyanobacteria; specifically with high Saginaw Bay water temps. With clear water, sunlight manages to penetrate the depths and grow the algae at the bottom of the lake. When algae die it floats to the surface and acts like a sponge, capturing E.coli and fecal runoff from farm fields sprayed with animal waste and overflow septic systems. The first reports of the smelly black muck were reported near Nayanquing Point State Wildlife Area on the western edge of Saginaw Bay. However, if the lack of rain continues then the risk of an algae bloom is reduced.
More Lake Effect Snow A Possibility
If the warm temperatures continue to rise the surface temps of the Great Lakes it’s possible that more lake effect snow may occur, particularly in Michigan’s Upper Thumb. If the lakes don’t freeze over during the winter months the open water provides cold prevailing winds a source of moisture for snow. Open water along three sides of Huron County at the tip of the Thumb could mean a very snowy winter.