Packing for winter travel

We pack nearly same for winter and summer. Our short sleeve shirts become long sleeve, add long underwear, medium weight wool sweater replace the light weight sweater. Add a fleece vest under the rain jacket, add a scarf, stocking cap,gloves and, maybe - if it is really going to be cold, a synthetic turtleneck. Adds very little additional weight.

I know I've said this in other posts, but silk can be very warm, and takes up very little room in your suitcase. I bought silk longjohns and undershirt. I bought a beautiful silk blouse. I just love wintersilks.com. It's affordable. I don't work for them, just a happy customer, so this is not spam!
One week from today, I'm going to Italy! Because I'm going to the Swill Alps also, I shopped for winter clothes. I'm traveling only with a medium sized backpack, and I fit in my silks and everything else very well. I wish I packed warm clothes like this last November when I went to Berlin and Prague! COLD!!
PS. Silk is great for men as well as women. I love men in silk!! LOL!

Pack essentially the same. The only real difference between winter and summer travel - where you would have packed lightweight acrylic socks and sweaters, instead pack medium weight wool sweaters or polar fleece and wool socks.

I don't really do long underwear (unless I'm skiing) but silk is warm, very light and can be hand washed/dried easily. It takes up almost no room in your suitcase.

Waterproof shoes are a plus. If you know it will be freezing, pack a knit cap, scarf and gloves. Otherwise just pick them up in Europe if you find you need them.

Your wind and rain shell should be the same but will probably get a lot more use. Still rely on layers for warmth rather than packing a heavy coat.

I second the rec for silk long underwear. Also, I generally only take one or two sweaters--since they aren't next to your body and don't need daily cleaning, you can wear them the whole trip.

Dress and travel like an onion ;-))

Layers!
Trains and stores in Europe can be very overheated while winter is happening outside.
I travel all over the world:
long (silk if you can) underwear +
regular clothes + sweater,
+ Gilet (down-vest) and a lightweight-coat.
Everything light weight - you'll be good to go!
I take chashmere scarfs for warmth, variety and color. European women love scarfs, so that is a good fit and easy accessoire.
Happy travels!
Good socks, comfortable walking shoes.

Unless you will be hiking the Alps in January

As Corinna and others have said, think layers. Start with a rain shell (no insulation, just the shell). That keeps you dry and the wind out. Then you add/remove layers as needed based on your activity level (walking, sitting, etc) and the surrounding temp.

You can find lots of info on the web if you google the topic.