I've let meat hang as long as 7 days before, with know problems, and know people that let it hang for 10 days, especially when it barely gets above freezing during the day. When it's as cold as you say it is, the meat isn't going to go bad. Even if the day temps get up near 45 to 50 degrees, and you keep the meat in the shade, you shouldn't have any problems for a few days. Just make sure that the blood shot meat and the hide are removed, and you won't have any problems.