If you are traveling and get caught in a snow storm or blizzard, or slide off the road, this emergency kit will probably save your life. It's easy to get lost or disoriented in a snowstorm. Cars are easier to find than lost people. Conserve your battery. If you are in trouble, flash your lights three times when a car passes.
Batteries go dead fast in cold weather.
Get something that stays warm when wet. Down-filled bags are warm when dry, but you'll freeze if they're wet. Don't eat snow. It takes more energy to melt it than the benefit you get from the moisture. Water-proof matches or Emergency Road Flares to light a fire.