You guys are freezing me!
One big thing to watch for, and it don't have to get much below freezing, is water freezing in the small line to the unloader (check the compressor to see how the unloader works on the particular model) that can cause the pump to fail to relieve pressure while in the stop mode. When the tank pressure falls to the start setting the motor will then have to try and start the pump turning while under pressure which requires a great deal more torque. If the motor has enough starting torque and the belts are tight enough it may start ok but it still is a heck of a load on the motor and quite often it will fail to start and trip the breaker or it may start slowly causing overheating problems on the motor or it could damage the belts and possibly the motor itself, a drop of water is all it takes to cause some big problems!