Because of the extreme elevation range in the parks, weather varies greatly from area to area, and mountain weather can change quickly. Opening and closing dates for facilities and services may change due to weather or other circumstances.
Most people who travel to these parks come in summer. Temperatures in the sequoia groves are comfortable and offer a break from the heat in the foothills. Reservations are strongly recommended for summer camping and lodging.
Beginning in September, weather usually begins to cool at night, though days may still be warm. The weather changes quickly, with hot days followed by stormy days. Light snows that melt quickly may begin in late October. Facilities begin to reduce hours or close, and fewer ranger programs take place. The Mineral King and Cedar Grove areas close for the snowy season.
When it begins to snow, sequoia groves are snowy, peaceful, and cold, and rangers offer free outdoor activities. The timing of our snowfall varies widely and can be difficult to predict. Tire chains can be required along park roads at any time. In the foothills, temperatures are cool and ideal for hiking. Hillsides are green and decked with wildflowers starting as early as January. Solitude is abundant.
Depending on the elevation, spring in these parks generally lasts from April to mid-June. Sequoia groves are often still snowy at this time of year, though snow begins melting at most elevations. Late spring snowstorms are common, and it's a good idea to check weather forecasts before you visit. Tire chains may still be required along park roads at this time of year. Rivers and creeks become especially swift, cold, and dangerous. Spring brings warm weather and abundant wildflowers to the foothills.