Originally Posted by
Gladiator
Frostbite, not breathing, is the main problem in low temps. If it is windy it does not even have to be very cold to do damage.
It still has to be pretty cold to worry about frostbite-- wind chills below -18F (-28C) for 30 minutes on exposed skin. That means actual air temperatures below 0F (-18C) along with high winds. NOAA (the US weather agency) doesn't even issue wind chill warnings until the wind chill is below -25F (-32C), IIRC.