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Boreal Community Media

Great Lakes water temperatures soar after recent heat

Jul 06, 2018 11:56AM ● By Editor

 By Mark Torregrossa of MLive.com - July 5, 2018


The Great Lakes surface water temperatures have warmed considerably in the past few weeks. Most of the Great Lakes are at the warmest average temperature right now compared to this date over the last five years.

Current water temperatures

Just above are the current surface temperatures on the Great Lakes. Lake Superior is the only Great Lake currently not much warmer than long-term averages. Lake Erie and Lake Ontario are much warmer than long-term averages.

Lake-superior-temp-vs-avggif 
Lake Superior water temperatures

Lake Superior average surface water temperature now (red line) is almost right on the long-term average (blue line).

Lake-Michigan-temp-vs-avg-jul5gif 
Lake Michigan is much warmer than average

Lake Michigan's surface water temperature has surged over the past few weeks. The entire lake average surface temperature is 67.8 degrees. The long-term average is 61.9 degrees, making Lake Michigan 5.9 degrees warmer than the long-term average. That's a lot of extra heat for that large amount of water.

Lake-Huron-temp-vs-avg-jul5gif 
Lake Huron even warmer than average

Just above is the Lake Huron average surface water temperature. Lake Huron is 6.2 degrees (F) warmer than the long-term average.

Lake Erie is seven degrees warmer than average

Lake Eire's average surface water temperature is now 77 degrees, which is seven degrees warmer than the long-term average. The warm water will be one factor in the severity of Harmful Algae Blooms in the next few months. Warmer water will increase the risk of a Harmful Algae Bloom.

Lake Ontario the warmest from normal

Lake Ontario's surface water temperature graph shows the water temperature going straight up. Lake Ontario is now 7.5 degrees warmer than average, making it the Great Lake farthest from its long-term surface average.

We usually see these water temperatures by late August. With the continuation of warmer than average weather, the Great Lakes could get really warm by late July.

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