Winter bicycling: a short guide
1. You will probably overdress.
I've found that all you need until it gets to around 15ºF is a t-shirt under your jacket.
Once it gets below 15º and until it gets to around 0º, all you need is a collared shirt under your windbreaker.
Once it gets below 0º, you will probably need to wear tights/long underwear and a light jacket under your windbreaker. But, don't overdress! It is better to be a bit cool than to overheat and sweat. The sweat condenses and you get cold.
You might feel cold for the first mile, but if I do 40-50 pushups before going outside, I stay warm—I know some of you are saying you will need to go to the hospital if you do that! :)
2. Your hands will get cold—unless you wear mittens. I use leather outers and wool inners. We called them "choppers" when I was a kid. The two piece is nice because it allows you to pull the inners out and let them dry if they get wet.
3. Your head will probably be warm enough, but you should invest in a mask-type stocking cap. I usually end up pulling it back, but the neck part is handy for keeping cold air off your chest.
3a. Keep your chest warm. If you don't, you might end up with bronchitis, which is why I suggest a mask type stocking cap. They usually have a neck portion that goes down over part of the chest.
4. Studded snow tires aren't what they are cracked up to be—an exception might be the $200 ones, but I'm not going to find out! I've run studded snows for 3 years now, and they do grab on snow and somewhat on ice, but they slip on corners pretty badly when there is no ice or snow. And the studs come off over time. I won't be replacing them with studded tires when they wear out. Now, if some bicycle tire manufacturer is looking for somebody to test those nice $200 tires, contact me...I ride 11 miles per day, 5 days per week, year round...
5. It is a blast riding in the cold and snow! The most fun is when it is -20ºF and people's jaw drops as you go blasting through an intersection with your beard all frosty and your hat down because you are too warm.
Enjoy the winter—if it ever decides to arrive!