You can carry a torch. That works. But no, we don't know wether you will have to enter a cold area before getting the jacket but because of the open nature of the game I would suspect that you can find warm clothing in the great plateau so you can approach the cold in different ways.We don't know if you'll have to enter the cold areas before you get this cold weather jacket. . . so the cold weather elixirs might be needed in the game. Or some other way of not freezing in the snow.