I'll take a cold snow during the rut anytime over a hot temp rut. While the books say the shorter daylight brings on the rut I've seen over and over a warm spell kill any daylight activity. So if you are hunting and your rut is on, the cold temp will heighten the activity, seen it too many times to argue. Get out and hunt beats anything else especially work. The deer may take that late morning stretch and being there when they move is what's it's all about.