Both previous comments offer excellent advice. I'll add one more thought:

If the roads are terrible, don't feel bad about leaving the bike home for a day. Let the plows get out there and do their job and enjoy the ride the following day. I know I have the LEGAL right to be out on the road, but if there is a lot of snow and slush on the road the other vehicles on the road are going to have a hard time passing me. The more I slow down the other vehicles, the more like they are to make an un-safe pass.

Today for instance I left the bike home. There was already a few inches of snow on the road (very drivable for now), but we may get anywhere from 5" to 12" by the time I go home tonight depending on how the wind shifts around. That is just not a good day to be outside on two wheels. My car also has top quality snow tires, so I take car safety seriously as well. Once the snow stops the crews around here do an excellent job of clearing the roads. Usually within 6 to 8 hours of the snow having stopped falling, the roads are so well cleared that even the shoulders are completely clean. So far I've only had to cancle my cycling about 7 times this winter due to bad weather. That means most of the time I am still able to be out there and have a great winter ride.

Don't underestimate the usefulness of studded tires. Even in the early Fall there can be some surprise icy spots on the roads. You only need to go down hard once to realy appreciate what that extra margin of safety will get you.

Happy riding,
André