I don't have any suggestions, but I feel for you. We're in Indiana too and getting one heck of a beating with this wind. My baby is still at the breeders, so I don't have to worry about her right now. Our big Golden loves the snow! As a matter of fact, she'd rather be out than in.
Do you keep them on a harness when you take them out?
I think as long as you have an area shoveled for them, they'll be fine
Good Luck and stay warm!
BTW, HAPPY BIRTHDAY!