just like most in midwest here in NW Indiana the temps change day to day 50 one day 5 the next...water big problem but like alot have said a fan on low works great

 

I've heard a bike cover with a low watt light bulb in a drop light under it will cure it. Never tried it myself.

 

Run an extension cord out to the garage and put a trouble light under the bike. Use a 60 to 75 watt bulb. It will keep the motor warm enough to keep from building moisture up both on the outside and inside.

This is a very old shade tree mechanic trick to help a car start in cold weather.