They are going to get some rain and snow in the Valley this week. As mentioned Glacier Point and the Tioga Pass roads will be closed.
Just drive around the Valley. As you arrive into the Park, keep an eye on the river before the road becomes one-way...nice rocks in the river. Check out the bottom of Lower Yosemite Falls, wander in El Capitan Meadow, take a short hike up to see Vernal Falls from below or a short walk to see Bridalveil Fall. Drive up 120 to see Cascade Creek Falls from the road bridge. Take the shuttle to Happy Isles. Take a stroll along the Merced River...lots of trails.
For culture, check out the Yosemite Renaissance show (multi-media competition) at the Indian Museum.
Take lots of pictures!