Sometimes (at least in my opinion) what you keep/put in the car during winter can be as important as the preparations you make to the vehicle itself.
Back with my first car (a 1980 Dodge Aspen) [eek], I had an experience that the following items in the trunk would have proven invaluable:
Shovel
Small bag of rock salt and sand.
Jumper cables
a thick blanket and/or big warm jacket
a cell phone
It was a very cold night, and I had none of the above in the car. There was about 4 inches of snow on the ground, which typically didn't cause me any troubles in my area. I was dropping off a friend (who lived in a VERY small town, out in the sticks, with lots of curves and hills, and a very limited plowing crew) it was about 1:30am when I got him home.
On my way out of his area, there are only 2 roads out. About 4 miles into my journey home I reached a hill (on a curve) that I couldn't get enough momentum to make. On about the 4th attempt, the car made it maybe half way up, spun and went nose first into a huge snowbank. The car was in the snow up to the center of the front tires and the rest of the car was sticking out accross the road.
After numerous attempts to pull out, (or even dig out with my hands) I realized I was freezing and I wasn't making any progress. I left the hazard lights on in hopes someone would see the car before plowing into it (no street lights either), and set on my way to find a house so I could call my friend.
About a mile down the road I found a house, had to wake the people to use their phone (tough sell in the dead of the night being a 6 foot tall guy, with running eyes, nose and a beet red face). My buddy came out and we got it out (eventually).
The moral of this story is, if I had the above things in the car I likely would have "recovered" in 5-15 minutes with minimal trouble. But instead, the car wouldn't start by the time we got back to it, the entire ordeal took well over an hour, I got really sick, and there are a few areas that are just a couple miles further out where it's likely I wouldn't have made it to a phone at all, and probably wouldn't be here today to write this incredibly long-winded story
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