Cold weather is different for all of us. phat gets much more cold than we do down here.

My winter clothing system (for camping) is not jacket based but rather "uniform insulation everywhere" based. I ski with my pack wearing long underwear, a 200 fleece jacket under a paclite parka and paclite zippered pants. When I get to camp I have a goretex shelled expedition parka weighing 40 ounces and a pair of goose down goretex shelled bibs that weighs 32 ounces. Add warm gloves and a hat and its 5 pounds of clothes that I can sit around in at -5 F. Obviously this gear also extends the range of my sleeping bag system. BTW I take the bibs off and put them inside the sleeping bag to keep them warm, and the down coat goes over my torso over the sleeping bag. I wear the large paclite pants over the bibs to keep them dry so no moisture is carried into my sleeping bag.
Jim