Lt. John Flannigan, commander of the Vermont State Police Traffic Safety Unit, told OnTheSnow that speed is the No. 1 contributing factor to winter accidents.

No. 2 is failing to leave enough room between you and the car ahead.

"People say they are going the speed limit, but the speed limit is intended for ideal conditions: daylight, good visibility, dry road conditions. Anything less you really ought to reduce your speed," Lt. Flannigan said.

"In winter you have to reduce your speed to maintain control at all times. If you hit a slippery stretch of road, and go into some type of slide, stepping hard on the brakes isn't going to help you. You have to hit and release, hit and release your brakes so you can lose speed and still maintain control," he said.

"In Northern New England, you can get some really adverse weather. Conditions can change very quickly, in a matter of minutes. You can have a wet road, then temperatures start falling, and you can get icy very quickly," Lt. Flannigan said.

"So first of all, go slow. Then leave sufficient space so you have time to react and come to a safe stop. Under ideal conditions, the 3-second rule is good to follow. That's where the car ahead of you passes something and you pass that same thing 3 seconds later. At faster speeds in inclement weather, back that off and add more time," Lt. Flannigan said.

He also said drivers should make sure they have winter tires for traveling in Northern New England, rather than all season or summer tires.

He suggested a winter kit, with a minimum of blanket and flares, with possibly other safety items such as non-perishable food, in case of getting stuck in remote spots in bad weather, where help might be some time in coming.

"A lot of people rely on cell phones," he said, "but in a lot of places there's no service."

Like cell phones, four-wheel drive vehicles may offer a sense of safety that's not warranted.

"We see a lot of four- wheel drive vehicles off the road. People have a sense of invincibility in a four-wheel drive, but it doesn't really help when you're stopping," Lt. Flannigan said.

"If I had to pick just one thing to talk about, it's speed when it comes to winter driving. Go slower. Drive according to the conditions. That's subjective, but if things are icy and there's snow on the road, you have to assume it's going to be slippery. Give yourself extra time to get to your destination, whether going skiing or going to work," he said.

We were driving on Route 100, southbound to Dover and Mount Snow Dec. 12, when we encountered an accident. The road was quite slick from a quick storm that had dropped wet snow on cold pavement, where it formed a layer of ice. A Chevy Suburban was being pulled back onto the road by a wrecker. A Vermont State Trooper was stopping traffic.

It was a good illustration of everything Lt. Flannigan told us.

More information: OnTheSnow's Winter Driving Guide.