I haven't spent too much time on the south side of the chain, but I had to rescue a couple of stranded boaters today. They were stuck in the mud on the channel between Fox Lake and Grass Lake just east of Crab Apple Island. My guess is that their boat is still out there. I even had some trouble even though I only draft around 12 inches.
On the plus side, temps are further along than I had thought. Average surface temps were around 55. The highest I saw was 60, so it's probably worth going out - just be careful!