You can go out and spend tons of money on your outer layer, because its the most recognized layer of any outdoor enthusiast, and lets be honest, steeze (how you look) is pretty important right now (even if you dress in all black to keep it low key, that is still your steeze.) But if what is under your expensive outerwear is an accident, then your expensive gear might as well be from walmart. Layering clothes is super important to being comfortable on the mountain and sometimes surviving a nasty night in the winter.
During an average ski day you partake in a ton of different events. You get out of your hot house, to a cold car. Your car warms up, then you get out of it at a cold mountain covered in snow. You sit on a cold lift for 10 minutes then ski your brains out through bumps, airs, carves, jibs and hand drags. Your heart rate increases, you get warmer. You might sweat. Then you get on the chairlift again sitting there and your heart slows down and you cool off. The cycle continues for your whole ski day.
The only way to stay comfortable is to layer up. Here is how I (and lots of other people who know whats up) do it.
BASE LAYER: Touches my skin, it must be made from something that will help regulate the temperature of my core and insulate when i sweat. Typically i wear a lycra spandex on my top and polyester spandex bottoms. I have lighter base layers like a polypro or a steezy golf shirt for warmer days.
THERMAL LAYER(S): A thermal layer is designed to trap air (body heat) thermal layer should be loose. There are a few styles of thermal layers, long john style underwear (with the mini squares) is cotton a time tested thermal layer. Natural fibers tend to be more comfortable (think Seinfeld and Yankees uniforms) . There are wool thermals, fleece, down and polypropylene. Depending on my activity for the day i must choose what layers I will need. If I go out at 4am and hike for 8 hours I am probably going to need 2 thermal layers. I cam shed one when the sun comes up and open my jacket if i get too hot, then put it on when I get to the summit and start to get really cold. I wear gym shorts on my legs, I find that does the trick.
OUTSIDE LAYER: Waterproof, windproof, breathable. The only time I want to take off my jacket is if I am getting my bronze on or totally dying of heat exhaustion. I find that if my outer layer has good vents and the fabric has good breath-ability I can even keep it on often in the most strenuous southerly exposed hikes. I don’t want any insulation on my outside layer if I am going to be moving around that day, because that’s what my under layers are for. If I am going outside to do nothing but sit around in the cold (winter camping) I am going to want a packable down jacket.
AND REMEMBER that when your tall tee is hanging out of your jacket and dragging through the snow, that will get your whole body wet, so if you have a tall tee on over your other layers, tuck it in while you are shreading, take it out apres!