There are two reasons why it's not wise to drive a car with a near-empty gas tank. First, condensation is more likely form in the fuel tank, which can cause starting and operating troubles.

Second, if you must drive in blizzard-like conditions, an empty gas tank could be very costly. Traffic delays are often greater with bad winter weather; what might otherwise be a short journey may become long and you could very well run out of fuel. Also, if your car breaks down and you're stuck on the side of the road, you'll need fuel in your gas tank to keep the interior warm.

Related Autos links:
How to survive being stranded
Your first winter: What to expect and how to cope