Mark,
Here in SC we sailed all winter long. Of course, the lakes don't freeze,  but 
I've gotten to the boat only to find frost and some ice on the hull. It  
warms up nicely by mid day, but a good hot pot of coffee goes a long ways until  
the sun warms things up.
The IMF main grunts and groans a few times coming out and the genny likes  to 
stay curled up until the sun warms it, but it is all worth it. There are few  
recreational boaters out on those days, mostly fisherman and their numbers 
are  few.
 
Rummy