I ride year round. Of course, it only dips down into the mid 30s here during the coldest months but I do commute in those temps. It was in the low 40s twice this week alone and I still rode to work. I find that if I'm cold starting out I'm usually fine by the end of my ride since it always warms up a few degrees, and so do I, by the end of a ride. If I dress so that I'm warm starting out I'm usually too warm within 20 minutes.

This morning I set out on a ride in 52 degree weather wearing only my bibs, short sleeve jersey and arm warmers. It was mighty chilly at first but it warmed up to the mid 60s by the end of my ride and I was totally comfortable when I pulled into my driveway.

It doesn't take much to ride in 30 degree weather though. Full finger gloves, wool socks, some heavy tights, a decent base layer along with a full sleeve jersey and a windproof outer layer. A headband that covers your ears helps greatly too. You could probably have picked up all that gear for the price you paid for those bibs.