When the Weather Outside is Frightful, Skidding into a Tree and Catching Fire is NOT Delightful
The most dangerous time to be driving when poor weather conditions exist is when the rain or snow first begins. This is because the oil and dust on the road has not yet had a chance to be washed away, so the pavement is at its most slippery. Slow down, and turn on your windshield wipers, headlights, defroster, and radio. Radio optional.
If the weather is really bad (you cannot see more than 100 feet ahead of you), reduce your speed to 30 mph or even less, depending on the road conditions and heaviness of traffic. You now have to watch out for snowmen as well as pedestrians, and snowmen move much more slowly. Their line of vision is also often obscured by a carrot.
If you live in a particularly snowy climate (aka all of New Hampshire), keep chains in your trunk and know how to use them. These are to be fitted to your tires, NOT to keep prisoners secured in your dungeon, but who are we to judge?