Visitors are urged to avoid arriving at park mid-day, due to anticipated high visitation
From The National Park Service:
Yosemite National Park anticipates an extremely busy Memorial Day weekend. Its been a very busy year so far and the park expects high visitation, especially from Friday afternoon until Sunday. Visitors are strongly urged to avoid arriving at the park during the peak hours of 10:00 a.m.to 2:00 p.m. Arriving early in the day or late in the afternoon are the best ways to enjoy the park. Once in the park, visitors are urged to park their vehicles, and enjoy the park utilizing the free shuttle bus service, bike paths, and hiking trails.