Originally Posted by
Seattle Forrest
You don't want the warmest jacket you can find, those are for standing in line at the ski resort. Wear one while you're moving, and you'll drown in sweat. Why would you spend $200 on a jacket that you can only use in such limited conditions? Get one that isn't insulated - even a wind breaker will do with the temps you're talking about - and wear a wool sweater under it when it's very cold. Take the sweater off when it gets warmer.
+1
I found a wool vest on sale and grabbed it for just this purpose. I like the vest option better because the arms can get a bit tight on my jacket. I can always add arm warmers if necessary. I was snowshoeing last winter in single degree temps with just a mid-weight wool base layer and a vest. I had a shell on but it wasn't windy and I was getting too hot. On a bike you want the wind protection.