We have over a foot of snow and sub zero temperatures. I still open the chicken door for the chickens and guineas to get out during the day if they want. Since the snow, they have been staying inside or within 6 feet of the door. Three guineas decided to fly up to the trees and not come in at night------HaHaHa, I left them out, boy were they ready to come in the next morning. Every few days another (or same?) guinea or two decides they don't want to go up and has to relearn that freezing in the trees with the owl hooting around all night is not something they want to repeat. (the chickens seem afraid of the snow, they don't come out just step out and return,) I have Twenty Guineas and Forty Chickens sharing the coop, the Guineas hog the top bars of the roost.