I usually use two or three different layers on the torso as the temperatures drop towards freezing and below.

The role of the outer layer is to protect you from the wind since it can easily pull all the warmth away from your body. Most any wind resistant material (e.g. nylon) should work. I avoid wind block materials like GoreTex since they don’t breathe adequately despite all the marketing hype.

Some tips to look for in good cycling outwear are:

• Is it light in color and with reflective striping? The days are shorter in the winter so you may be riding more in the dark. You need to be seen.
• Is there a zipper flap? Without a small amount of fabric behind the zipper, wind can rush right through the zipper.
• Is the back cut a little longer? You’re bent over when cycling and you don’t want that part of you exposed in any way.
• Is there venting? Sometimes you’re just going to generate more heat than you need. Rather than overheat, your jacket should have a means for venting some of that heat. I prefer rear back flaps but it seems more manufacturers are into pit zips.

This winter I’ve been wearing Patagonia’s Cold Track jacket. It’s has a thin internal layer of insulation, which seems to work. I prefer my outer layer to be minimal because it can be worn many more times without getting washed. Minimal washing is a good thing for outer layer durability, especially those that rely on embedded materials for their water resistance.

I’ve also had very good luck with an MEC cycling jacket as well as some from Pearl Izumi. Unlike Patagonia’s offerings, these are more generous with the reflective materials, including Scotch-lite reflective taping.

Under this outer protection, I’ll wear an insulating layer of varying thickness. My typical choices for this layer from lightest to heaviest are Patagonia’s lightweight Capilenne, R0.5, and R1 tops. I really like the Patagonia R0.5 and R1 material. The internal waffle design seems very efficient at moving perspiration. In additi0n, they resist odors better than most synthetics.

Now in very cold conditions I will sometimes throw a thin mesh sleeveless layer on as my first layer. I have some from REI, Patagonia, and Pearl Izumi. I think they all work the same.

One other tip is if you’re unsure about whether you are dressed warmly enough (or too warmly), do a short 1-2 mile practice loop and circle back near your starting point. This gives you the chance to make adjustments as needed. But, as you ride more in the winter, picking the right clothes for the conditions will become second nature.