Greetings Paladin I dove on Lake Huron quite a bit last season and many divers wore farmer Johns 7mm or 8mm.
The average dive times of a wet diver are in the 20-30 minute range, dry suit divers are 40-60 minutes on the shallower wrecks.
It was a blast up there last season and I can second the GLWC to find good dive ops.
Great Lakes Diver aka Bruno's Dive Shop would be one to start with.
They are a great group of instructors and friends who can put you on good wrecks with in your skill range and have fun doing it.
They have a house in Port Sanilac that they allow camping and the Blue Water Pub is outstanding cold beverages / pizza!
Out of Chicago Windy City can put you onto several wrecks that are excellent.
They just purchased another dive boat so they will be offering even more dive ops in 2012!
We started our wreck season with them in Lake Mich. them over to Huron for the rest of the summer.
If you had time the Ship Wreck Museum at Whitefish Point in MI is outstanding.
The Chris Kohl books are a great start to the research that make diving the Great Lakes a blast.
The history in them will make you numb and the exploration still going on today will excite you!
A group of divers discovered a new wreck last season in 60' of water and still many wrecks unaccounted for.
The Great Lake experience is unlike any other the waves, swells, currents, cold, and the divers you will meet!
More fun than should be allowed awaits you!
That sums up my wreck season last year!
Come on up and enjoy, I can set you right up with the people to make it happen!
CamG Keep Diving....Keep Training....Keep Learning!