Deer most certainly are effected by severe conditions. Just ask Maine, who despite having relatively low deer densities still have winter loss regularly, and at times a significant portion of the herd.
Deer burn alot of calories just walking through that stuff, and staying just staying warm in very cold conditions.
Deer might be able to reach a very slight bit higher up , but remember, they dont walk on top of snow. The very small narrow shape of the feet and legs are not conducive to walking on snow like a snowshoe hare. They sink straight down into it.
There will most likely be losses. Perhaps not as severe as some states, but some fawns of the year wont fair well.