Most people tend to way overdress when they run in the cold. Not me. After all, I was hatched and raised in the islands. RULE OF THUMB: Wear more than you think you need. You can always take off a layer.
When I began running today it was 32 degrees. I found the experience totally invigorating and refreshing. You should try it sometime. Your snot freezes, which in itself makes the experience worthwhile. I even wore mittens. They were snug and believe it or not they really do keep your hands warm.
The moral of the story? Don't stop running just because it's cold outside. Layer, and be sure to keep your hands and feet warm.