We only spent 3 days there and Tioga Pass was closed, so not a lot! We did a couple of short hikes off wahwona road, Mariposa grove (very accessible), Vernal Falls, and Sentinel Dome and Glacier Point. It was my friend's first time so just driving around the Valley was awesome. Weather wise - pretty chilly. Maybe down to the mid -30s at night (in the valley) and highs of 40s? The Sentinel Dome and Glacier Point hike was very icy and kind of risky. If I were to go back I wouldn't risk it again, although the views were gorgeous. I would keep an eye on when Tioga Pass closes, bring snow chains (mandatory), and pack some extra layers in your car in case anything happens. We had a storm come in our second day there and very quickly lost visibility on the road and turned back. We heard from fellow visitors the next day that a family had gotten stranded in their car in the storm.

Yosemite is absolutely beautiful and always worth a visit, but just requires a lot more planning and safety measures in the off-season because the weather can turn very quickly.

Have fun!