While there are many trails that are closed for the winter, there are plenty that are still accessible. Many of the lower trails in the Valley, such as Bridalveil Fall, Mirror Lake, Lower Yosemite Falls and the Vernal Falls footbridge on the Mist Trail stay open through the winter. But, trails that take you higher in elevation, like Upper Yosemite Falls and 4-mile Trail are closed. The cables for Half Dome are taken off at the end of October. However, Hetch Hetchy and Wawona remain open all year, and their trails will be snow-covered, but they will be open. You can read NPS’ current conditions before heading out for the day.
Early mornings will be chilly, so be prepared with hats, gloves and warm layers. It will get warmer throughout the day, so bring a daypack where you can put your layers as you take them off. Even though it is cold out, make sure you are still drinking plenty of water throughout the day. Plan on starting your hike around 7 or 8, and make sure you can finish it within 6-8 hours due to the shorter days of winter.