I see a lot of people here in heavy winter coats, goggles, insulated gloves and so on, at 45 degrees. Not that I'm laughing at them - I have a windshield so I'll be the last one to put on a macho air about it. But for what it's worth I've learned that keeping your lower legs warm helps keep your feet warm, and the same goes for forearms and hands. Then cover the face somehow (wrap, balaclava, helmet plate or whatever), and as long as you can keep a good pace up you're golden for the temperatures we mostly get around here.