Lake MI
I have sailed Lake Michigan for a number of years. Two years spent on an O’Day 22 and the remainder with a 30ft O’Day. Of course, experience is a big factor. Lake Michigan can get ugly quickly. If the experience is there and the weather cooperates, you’ll be fine. My personal choice though would be to sail within sight of the coastline if sailing a 20ft boat - but I prefer to err on the safe side. I got caught in severe weather in my 22ft and had to take both sails down and motor into five footers – not fun. Rain and lighting completed the experience. Try July and early August for the most stable weather patterns. My 30ft boat has increased weight and provides a much dryer ride in rough weather. I often go out in weather that would have kept me at the dock with my 22ft. Best of luck!