With the weather where I live dipping down into the single digits (Fahrenheit, it's been below zero Celsius on a regular basis for weeks), I thought it would be a good time to discuss some strategies for dealing with the cold.
First of all, if money is no object, there is a ton of fantastic cold weather gear out there, both in high-tech synthetics and traditional wool. Most of it works fine, some of it works great, and none of it's cheap. You do get what you pay for, and if you're willing to take the plunge it's worth adding a few items to your riding wardrobe, but be prepared to spend a few hundred dollars for some good winter kit.
For me, the worst thing about cold weather is the wind chill. I'm usually fine with some brisk morning weather, and have lived in much colder places than I do, but when the wind kicks up, it's a whole different matter. Clothes that were warm enough a second ago suddenly feel like lace doilies and fingers and faces turn to pink icicles.
Even if the wind isn't blowing, riding along creates its own wind, which means the more you move, the colder you get, as shown in this chart:
|via Chrome Capital|
So possibly the first winter riding tip I can offer is one that will cost you nothing: ride slower. Not only does slowing down a bit reduce the wind chill, but it gives you more time to watch out for snow and ice. Obviously, you still have to get where you're going, but leave yourself a little extra time and take it a bit easier if you can. Of course, you can also bundle up against the wind chill, in which case riding faster will mean you generate more heat, and you'll be warmer. With a little trial and error you'll find the sweet spot where "working hard enough to keep warm" and "not traveling fast enough to freeze" intersect.
My other favorite free winter riding adaptation is to grow a beard. This may not be possible for all of you, either because of workplace policies, youth or gender. But if possible, letting your winter coat grow in a bit does offer a bit warmth (my beard was full of frost this morning from condensed breath, but it since the icy bits were stuck to my beard and mustache instead of my skin, I was fine) and may make a positive impression on your fellow cyclists and add to your bike shop cred. Of course, if you don't have it in you to grow a full beard, you can always go for the prosthetic option, or... just wear a scarf I guess.
Gloves are essential, as your hands catch a lot of wind but don't move around enough to generate much warmth for themselves. In extreme cold a pair of ski gloves can offer both wind protection and insulation while still allowing you to work brake levers and shifters. For milder weather, I use a pair of work gloves. In particular I like the "mechanic style" gloves, which are elasticized to fit close to the hand and be less bulky than regular gloves. They are very similar to full-finger cycling gloves but at about half the price.
In addition to fingers and faces, ears can be vulnerable to wind chill. If you don't wear a helmet, a simple beanie cap can help with this. If you are a helmet wearer, this can be trickier, as you need something thin enough to fit under your lid. There are commercial headbands, skullcaps and balaclavas (which also help with noses and chins) available, but in a pinch you can get by with a plain old bandanna. Simply fold it into a wide "sweatband" and instead of tucking it up over your ears, use it to cover them. Then put on your helmet (you may have to loosen it just a hair).
|The beard is already defrosted by this point|
|forgive the lousy cell-phone-indoors pics. Also, the goofy-looking model|
As for the rest of your body, generally speaking, for short commutes, regular clothes and a jacket are fine (for example, for a quick couple of miles worth of errands this morning I wore jeans and a heavy sweatshirt), but on longer or more intense commutes you'll find that cotton clothing quickly soaks up moisture and loses any insulating properties it may have had. A number of studies have found that wet cotton actually transfers heat more quickly than bare skin, so you're better off naked than in wet jeans. You may have trouble explaining that to the police however, so wool, silk or synthetics may be your best bet.
While cycling-specific gear, as mentioned above, can quickly get pricey, your local department store often has fitness wear in various moisture-wicking synthetics, and cheap thermal underwear is getting easier to find (avoid the waffle-knit cotton stuff, while it might be plenty warm when you're sitting still, once you sweat it's useless). Look to layer. For example, start out with a moisture-wicking shirt, put a fleece jacket or vest and then add a nylon windbreaker over top and you've got a good upper-body covering down to pretty cold temps. On your legs a pair of synthetic long-johns under some nylon wind pants will work wonders. Warm socks are a must as well. The other advantage of layers as opposed to super-heavy garments is that you can mix and match to suit a variety of weather conditions, rather than only using them on the coldest days.
When I used to live up by Lake Ontario, and sub-zero winter weather was the norm, I turned to Military Surplus polypropylene base layers. These were about the weight and thickness of ordinary sweatpants and a sweatshirt, but way, way warmer. I you can find a set, throw a windblocking layer over top and you're good anywhere in the Lower 48.
There's a saying in the Netherlands, or Denmark, or one of those countries where everybody rides bikes around like it's no big deal all year, that "there's no bad weather for riding, just bad equipment." With a small budget and a little planning, you can tackle the coldest winter rides with relative ease.