Coldest packing lists

Cold weather packing is all about layers.

You can't bring three sweaters or jackets, but you can bring two or three outerwear pieces with various levels of insulation, and mix and match as you go.

With climates that get cooler at night, day packs are a must just so you can conveniently store extra layers which you can swap in or out as the day progresses. Super annoying to start a brisk morning off with a light jacket on and then have to carry the jacket around all day after you take it off.