when...

Boats are gone from Chicago area by Nov 1, Milwaukee about the same,
probably sooner up "at the top" in Michigan. Weather is still sailable,
but can get down to freezing at night. Usually no real cold until well
into December, if then. Storms any time.

April is sailable, but again still might get down to close to freezing
some nights. Boats start appearing in numbers in May.

Also, remember the "Edmond Fitzgerald". The lakes can put up real
weather very fast, any time of year. After getting beat to **** (nothing
to do with his race standings) one summer on the Makanack (sp?) race Ted
Turner publicly ate his words about lake sailing not being "real"
sailing. He skippering a large boat with a prefessional crew.

You have about a 5 month window on the Great Lakes, with a some
allowance at each end for cheating if you can put up with a little cold.

Sorry, can't speak to the east coast - I spent my "formative years" in
Chicago.

Rufus