Lake Michigan is an inland sea. You cannot sea across it and it get's windy just like the Pacific Ocean. Since there is very little salt content, the sand is a sugary white and so fine that it squeeks under your feet.
You get conditions ranging from flat water big kite to head high waves and small kites.
The best time of year for wind is Fall. It blows starting in early spring but is still pretty cold.
Check out pictures of Grand Haven Michigan here