In this part of the country, you can have shirtsleeve weather, or a blizzard, or both. You'll wear your heavy clothes for a few hours and then carry them the rest of the day. I hunted a southern CO hunt in 2009, and got 6" of snow one day. I try to carry enough clothes to survive if I had to spend a night out. I don't use wool or down. Heavy fleece works, but my favorite is Korean War era army long johns (slick nylon that slides on your knees). I have found nothing with a better weight to warmth ratio. A cool-max T-shirt, a micro fleece long sleeve shirt, Army jacket liner, Fleece hoodie, Rain Jacket. Those five layers have worked for me through any weather down to zero. Always Gore-tex boots, and gaiters. I wear fleece Glomitts, you can slip your fingers out of the mitten part to shoot, or tie your shoes. Fleece breathes, and keeps your hands from sweating too much. I use light Goret-tex mitten covers for rain or snow. I also carry a small 3/8" closed cell foam pad to sit on in snow or wet grass. Old Army surplus sleep pads are the right color (olive drab) and super light.