Late September sand castle near Otter Creek, on the shore of Lake Michigan just west of Traverse City. Temperatures are dropping here, and this well could be the last sandcastle of the season. Once daily high temperatures dip into the mid-60s, most of us lose interest in spending long days at the beach. And lounging in the sand lacks the charm of a hot summer day when skies are overcast and wind-driven sand grains pelt your skin. But the Lake Michigan beach still offers a great taste of nature – you just have to bundle up a bit.