At temperatures that cold it is much more difficult for the liquid co2 to change to a gas. You'll shoot hot when liquid co2 enters your valve. There's really nothing you can do about it.
A long time ago we used to set our co2 tanks around the fire (during the winter) and try to warm our the bottles after getting fresh fills. Many a burst disc blew when the tanks were over-filled (which is easy to do if you're not using a scale during the winter).