Yosemite is a remarkably different experience in winter . One thing for sure is you will not be bothered by excessive crowds everywhere. If you are lucky to visit just after fresh snowfall or even better while its snowing, I bet you will be transformed to a magical place. If you can find accommodation in the limited lodging facilities with heating that is the best option. While I visited the temperature had dropped I was driving from the warmth of Los Angeles and by the time I reached Yosemite in the evening they were out or heated and I ended up staying overnight la one of their very basic cavas tents with no heating,It was the best of lines and It was the worst of times!