Wow...but not by much! I can't imagine what your winters look like. Hope you get a good winter coop together. We put our chickens in the barn for the winter and on nice days they get outside...just not alot of them! Well...except this year it was pretty nice.
Chickens can be pretty cold hardy, especially certain breeds. What breeds do you have? My flock has lived through rain and sun and taken a beating from the elements. They seem to enjoy themselves.
Don't hesitate to ask any questions you might have, and enjoy the site.