I may not move fast, but I do move and stay upright. If the snow is light or fresh, I dig my cane through it, and with the combination of sound and touch I can tell what is there. If the snow is too deep to dig through or it is packed and frozen, the cane must find something above the surface to identify as a landmark. Sometimes packed snow on the sidewalk and loose snow beside it show enough difference to help. Taller landmarks are helpful, such as bushes, fences, sign posts, and parked cars.
Snow covers many of the usual landmarks, but it can become a landmark, itself.
One winter it stayed so cold for so long that I used a particular snow bank as a landmark on the way to a friend's house. When the snow is deep and soft, it weighs down branches which hang in front of you. One advantage of a long cane is that you can reach up and tap a branch so it will release its burden of snow before you walk under it. Well, it works sometimes. The world sounds different with a covering of snow.