The air temperature matters less than the temperature of your battery. The motors and electronics (except maybe the barometer) don't care how cold it is (unless it's really cold or you've made the mistake of oiling your motor bearings). I've flown at -5°F (-20°C) with room-temperature batteries and had no issues.
On the other hand I've flown at 20°F with fully charged batteries I inadvertently left in my truck overnight and got the low-battery warning the second I spun up the motors.
Those chemicals just don't react well when it's cold!