Dude, you should at least wear knee warmers. Riding in shorts in cold weather can be hard on your knees. I cover my knees for any temps lower than 65 F. You may be young and fearless, but things like that will catch up with you when you get older.

Temps were in the mid-20s F here, which felt warm after 15 yesterday and 9 the day before. However, I dressed quite a bit lighter, so felt just as cold riding. Pushed the pace a little to warm up, but the red lights weren't cooperating. My water bottle was slushy when I got to work; yesterday it was frozen solid.