Check the tires. Good tread is a must. Check the battery and alternator. Make sure you have a jack, lug wrench and spare tire. Often the reason people get into trouble on the road in winter is failure of the auto itself.
Poor tires are a big factor.
The so called all season radials are OK if all of your driving is on cleared and sanded streets, but if canyon driving or back roads driving is part of your agenda I would highly recommend some town and country tread. Good tread means the difference between getting there or not. You can't get moving at all if the car won't start. That is where the engine tune up and engine heater comes in. Gosh, it's frustrating when you have to be to work and the car won't start.