Keep two things in mind as you venture out into the chill. Batteries will drain much more quickly in the chill, so keep your equipment and spare batteries close to your body.
Cold film can become brittle quickly in very low temperatures.
Spare rolls should be kept as warm as possible, then exposed to the cold as briefly as can be accomplished in the process of changing rolls. Finally, when you return, seal your equipment in an airtight plastic bag before entering a warm environment. Open the bag only after your gear has returned to room temperature, thus avoiding the potentially damaging effects of condensation. It takes about an hour or so, and it is worth the wait. The best way to compensate for the excess light is to take your light meter reading close in on your subject.