My former club used to fly every January 1st no matter what, and at least one January or February "Chili Fly" with hot chili provided. 0ºF is pretty cold, -10ºF is very cold, but the glow engines did fine. The Monokote occasionally burst like a drum-head on a hard landing, and the batteries don't have the juice they do in balmy 45ºF weather, but the engines run fine.