Being Comfortable In the Clothing You Are Wearing In Those Precious Moments Of Travel Is Just As Important As All the Other Plans for Accommodation Car Hire Et Cetera.So here is my advice.

When the sun is out, even at 0° it can create discomfort if you’re dressed  in heavy garments by creating sweating.Full sun will make a vast difference to your physical discomfort, and if you’re wearing only one or two heavy garments, like a heavy Jacket and a heavy jumper,and you feel like you have to take them off ,and then you’re only wearing a T-shirt you will go from one extreme to another and feel the discomfort of exposure to the cold. This is why layering has become the new buzzword.Everybody will have different choices, mine, over 50 years of enjoying the experience of cold climate landscapes,  whilst searching for vintage clothing  for ABC television productions and major Australian feature film…have handled just about every fibre ever created… and  having experimented with both synthetic and natural fibre, have settled on this combination:

1.Silk T-shirts, I have found these to be outstanding in letting the sweat evaporate from your body, T-shirts… Particularly “quality”cotton can make you sweaty,…. nature makes you sweaty to cool the body down, and this is exactly what happens in extreme cold, you become colder besides being clammy with T-shirt trapped sweat. Another quality of silk is that it dries almost instantly after washing, a good feature whilst travelling

2.The next layer is a clever fabric technology from  silkliving click the link.It is a waffle texture fabric that they have named cellular, for obvious reasons made out of primarily silk 80%, and merino wool 20%. This is a longsleeved and I have a crew style and also one with a high neck zip, if the weather warms up, I might take the layer  no:3 …which I am describing next,which is the, “icebreaker” piece off, and  the silk body becomes quite classy as an outer piece also…. Or I might even wear one of their other formulations over the cellular… it is called “silkspun”, outerwear, made up of 72% silk, 13% Merino, and 15% cotton for a bit of extra strength, this gives another very subtle variation in temperature control when you didn’t quite want to go to the warmth of the merino. 

3.Another sophisticated,particularly for the outdoors, NZ clothing brand is the next piece to layer with from  icebreaker icebreaker I have several different styles from this company, several  sleeveless vests,… Tops,longsleeved high collar with zip tops, these come in three different weights, and I have more than one of each, for different colour codes…. I also where their underwear in the trunk style, on the odd occasion that I wear longjohns I prefer silk body, I find the full Merino a bit stuffy.

4.The final outer piece of clothing is a puff jacket with a hood (as long as it’s not raining when I would wear Gore-Tex) a jacket with a hood keeps the warm air circulating all through the upper part of your body without being released, if you just wear a jacket your neck is exposed and your head, this particular piece is not only my favourite jacket become iconic for many people, it is clever because it’s quite a thin layer but exceptionally warm, so you don’t feel like a snowman in a big puffy feather or puffy synthetic one. The name of this synthetic is Primaloft ( it’s just a word defining the fabric, as Gore-Tex is just the “fabric” made up by many different brands,..

5.My favourite brand for Primaloft is from a U.K. brand...montane .click on the brand word for link,this garment comes in different weights, defined in grams, my favourite ( when worn with all the previously described garments in 1. 2 .and 3. is their 40 g which is the lightest, this group of clothing along with moleskin trousers which I will describe separately will take you down to 0° comfortably.
Just

Just as a footnote: there are of course many other good brands I think another U.K brand  RAB the brand word for link, for their Primaloft. Another company I admire is smartwool smart barwool USA they have really luscious socks besides nice tops et cetera in fine Merino, all of these companies have a sophistication in the styles, finish, and technical quality of the garments
These are the garments I find make my travel experience no matter how harsh the conditions eminently bearable at the same time with great comfort, these companies know nothing of me it is just my discerning choices that put them in my wardrobe