Monday March 26, 2012

Lake Michigan water temperature, like our air temperature is much above normal for this time of the year. Typically, we see the last of our lake ice melt away around March 19, each year. However, last week there was no ice to be found anywhere on the Great Lakes with the record warm air temperatures. In fact, the water temperature near shore reached the upper 50's on the southern part of Lake Michigan. One factor that may not be as obvious, is the role of wind speed and direction in the record setting water temperatures last week. The surface water became exceptionally warm because of the low wind speeds kept the vertical mixing in the lake to a minimum. Therefore after a few days with air temps in the 80's and light winds, the surface lake water was able to rise 15-20 degrees in a single week. Last Sunday with the cooler weather we saw how gusty northwest winds brought the surface lake temperatures back down to the low 40's, or 15 degrees cooler than the temperature earlier in the week.