Originally Posted by Bob Ross

I haven't read any of the responses so I apologize if I'm repeating what's (hopefully) already been said. You'll do better with a base layer. You want to separate the moisture-transport functions from the insulating functions in your winter apparel. A good base layer will move the sweat away from your skin so that you don't get chilled. The air space between that base layer and your outer layer -- or, in colder weather when you're using a 3-layer system, the insulating layer between that base layer and your outer layer -- provide the warmth. A thermal jersey makes an excellent insulating layer, but doesn't do as well for moisture transport.