Decomp posted some good things ya could do if ya happen to find yourself sittin in a broke down car on the side of the road in a blizzard the other day. All of em were good ideas. Nothing wrong with anything he suggested.
In addition to his ideas, I would suggest ya might put a box or a bag of "possibles" (things which you could possibly use) in your vehicle. A blanket or sleeping bag, a flashlight, a portable radio (weather radio) Spare batteries. I have a POSSIBLES box in my truck and back when I was working I had a possibles drawer in my desk so that if I got snowed in there I could make it.

Liberals are like a "Slinky". Totally useless, but somehow ya can't help but smile when you see one tumble down a flight of stairs!