(1) Charge up all available cell phones before you leave.
Even the one you keep in the glove box just so you can dial 911 in a pinch. Get them all charged up, so that you reduce the potential variables that would keep you from being able to call ahead about emergencies and call family and friends to let them know what’s happened with you. The technology is available - use it.
(2) Keep an extra set of clothes or two available to you inside the interior of the vehicle. If you’re in a situation where you have to get out of the automobile for some reason, more layers of clothes are better. Make it as easy as you can for yourself to access these extra clothes.
(3) Take along some extra blankets.
(4) Pack some high-carb snacks.
(5) Put something heavy in the trunk of your car if you have rear wheel or all wheel drive.
(6) Grab your home first aid kit - just in case.
(7) Check two basic things on your car.
(8) If you’re ferrying children, have at least a day’s worth of their basic supplies along.

This list has been severely abridged. To read the full list, view the original post at it’s source:
Eight Frugal Ways to Prepare for Winter Driving (TheSimpleDollar)