Today was 5 degrees when I left the house, a little wind. I wore:
Capilene longies (top and bottom)
A fleece ear-cover head band
Helmet
Jeans
Knee-high wool socks
Fleecy wicking midlayer
Light rain jacket outer shell
Lobster mitts
I was pretty warm overall but really wished I'd worn a scarf. I don't know why I didn't. It's the first time it's been cold for real this winter so I guess I'm out of practice.