If you are thinking of doing some swimming, you may want to pick an inland body of water rather than go to Lake Michigan.

No, there is nothing wrong with the water in Lake Michigan but the water temperature has significantly dropped and it may take a wet suit to do any real swimming.

According to MLive, the National Weather Service has notified the public that beaches along Lake Michigan to make sure to let beach goers know there is the possibility of hypothermia if in Lake Michigan too long.

I have spent a lot of time in Lake Michigan with my son this summer and back in July the water was great. Probably warmer than I had ever experienced and it was consistent for quite some time.

At the end of July my son and I were at Lake Michigan five days in a row and the water temperature dropped quite a bit from the first day to day five.

For example, the beach water temperature in Grand Haven has dropped 20 degrees and right now is only at 43 degrees. Now that's damn cold water, almost Lake Superior like.

NWS meteorologists said, "the water is a little chilly again at the Lakeshore, and downright cold at Grand Haven! Whenever we see northerly winds for a stretch of time during the summer, we tend to see water temperatures drop along the West Michigan Shoreline. This can take days or more than a week to recover, and will depend a lot on wind direction coming up."

If you desire is to swim in Lake Michigan and no other body of water will suffice, you may want to head to the beach in Holland or even further south where water temperatures are a bit higher. Right now the water temperature in Holland is at 58 degrees but even that is a bit chilly.
Don't allow the little ones to be in the water too long either and be on the look out for symptoms of hypothermia.
The best alternative would be to find a friends pool or an inland lake where water temperatures are much higher at this time.