1. Know the difference between winter weather advisories. The National Weather Service issues several cautions, understand the differences between them before you hit the road:

Winter weather advisories inform of conditions that may be hazardous, but should not become life threatening when using caution.
Winter storm watch means that severe winter conditions may affect your area and is issued 12-36 hours in advance of major storms.
Winter storm warning means a storm bringing four or more inches of snow/sleet is expected in the next 12 hours or six or more inches in 24 hours.
Blizzard warning means that snow and strong winds will produce blinding snow, deep drifts, and life-threatening wind chill.
Let someone know your timetable and travel route. Especially important if you’ll be driving in less-trafficked rural or large park areas.
Prevention is the best Medicine – Driving slowly and maintaining plenty of room between you and the next car is the easiest way to avoid potentially lethal accidents. We all want to get to Christmas dinner faster but that extra 30 minutes could save your life. Allow for more three to 12 times more stopping distance depending on the size of your vehicle.
Stock your car with a shovel, broom, ice scraper, jumper cables, blankets, flashlight, warning devices (flares), sand or kitty litter, and high-calorie non-perishable food.
Keep spare, charged batteries for cell phones in your car. Duracell and others make instant chargers for popular devices like the iPhone. If your car battery dies, you will be glad you spent the extra $15 to reach help. If you regularly travel to very remote areas where cell towers are few and far between, consider investing in a satellite telephone or a service similar to On-Star.
Keep your gas tank full to prevent the fuel line from freezing. Also, make sure the windshield wiper fluid reservoir is full.
Check to make sure your lights and windshield wipers are functioning properly. In most states it is illegal to drive if either is malfunctioning–and in certain weather situations it is also extremely unsafe.
Know your health insurance plan’s emergency care policies. What kind of doctors can you visit? If you are only have in-network benefits what happens if you need medical care beyond your home city or state? Are you charged differently for treatment at a hospital emergency room (without being admitted) or an emergency walk-in clinic?
If you get stuck in the snow, stay in your car—it’s your best shelter. Don’t leave unless help is within 100 yards.
57.8% of accidents are the result of improper driving. Whether you’ve had a bit too much pie or a bit too much pilsner, don’t drive until you are fully awake and not impaired by anything. Most adults know well enough not to drink and drive, but few realize accidents are just as easily caused by being drowsy or impaired by legal drugs like cold medicines. When in doubt, pull to the side of the road or check into a motel for a quick nap.
And a bonus point: carry a first aid kit in the car with you. This is especially important if you have children or the elderly riding with you.