When to Go
Summers tend to be very warm, and triple-digit temperatures are not uncommon; luckily this means fewer crowds, especially on weekdays. Spring, particularly March and April, is the most popular season, as this is the prime time for viewing spectacular displays of lupine, poppies, and other wildflowers. Though late September can still be quite warm, fall is a great time to visit if you want to enjoy cooler temperatures and fewer crowds. Winters are cold by California standards, but this is an opportune time to hike, especially the High Peaks, where most of the trails are in the sun. On the other hand, the temperatures in the deeply shaded areas such as the Balconies Trail can reach below freezing.
One thing to keep in mind: Bear Gulch Cave, on the east side, is one of the most popular hikes and attractions, but it's also home to a large colony of Townsend's big-eared bats. This protected species raises its young in the late spring and summer, so the cave is closed from about mid-May to mid-July. If your plans include visiting the cave, check the park's website (www.nps.gov/pinn/planyourvisit/cavestatus.htm), which provides updates on closures.