Seasons

 

As is true of all mountainous regions, weather in the Sierra Nevada can change rapidly at any time of the year. Elevation plays a major role in temperature and precipitation variability. Since Yosemite varies in elevation from 2,000 feet to over 13,000 feet, the lower foothills of the park can be experiencing the rebirth of spring while the higher elevations remain in the grip of winter. The higher you go, the colder and more temperamental the climate gets. March, April, October, and November are transitional months when warm, sunny days can suddenly become stormy. Although summer in the Sierra is known for its sunny days, it is not unheard of for clouds to build up suddenly, creating a downpour that could last a few hours or several days.

The conditions mentioned below try to portray what's most likely, but conditions often vary significantly from year to year (there is no "normal" fall, winter, or spring). (See additional climate information.)

November through February

Winter in the Sierra is cold and wet, with over 70 percent of the year’s precipitation falling between November and March, usually as snow. The first snows of autumn are usually light and melt within a few hours or days, but by mid-November, the ground is generally cold enough for snow to accumulate, particularly at elevations above Yosemite Valley (4,000 feet). At higher elevations, snow may fall as early as September or October. The snowpack increases during winter and reaches maximum depth in March. Typically, snow coverage is consistent at elevations above 6,000 feet but by November or December, you should be prepared for snowy conditions throughout the park. While the floor of Yosemite Valley may not always be snowy, you will encounter snow as you ascend from Yosemite Valley, Wawona, or Hetch Hetchy.

It only takes a few inches of snow to completely obscure trails, requiring navigation by GPS (with paper map and analog compass as a backup). Additionally, hiking in the snow is very difficult and increases your chances of injury, so cross-country skis or snowshoes are best.

You should be prepared for snow and rain. In a big storm, you may need to stay sheltered for days. Be sure to bring extra food and stove fuel. Snow depths can be up to dozens of feet at higher elevations.

Be sure to check current conditions before making a plan.

March through April

Spring is a time of transition in Yosemite. While lower elevations may be in full spring bloom, higher elevations are still buried in snow, with rain or snow still possible. Weather can be warm and sunny one day, and cold, wet, and stormy the next. As snow melts, streams and rivers fill or overflow with runoff. Backpacking options remain very limited during this time. With warm and dry weather, the snow line may be higher. In March, it may be around 5,000 feet; in April, it could be around 6,000 feet. However, conditions vary considerably from year to year, especially in spring and fall. Yosemite Valley, Wawona, and Hetch Hetchy are all around 4,000 feet, so, assuming warm and dry conditions, it may be possible to hike to places like Little Yosemite Valley, Chilnualna Falls, or Rancheria Falls without encountering much snow. Even in good conditions, it is likely you’ll encounter some areas of ice and snow, along with sections of trails flooded. Traction devices for boots, along with waterproof boots, are a good idea.

Creek crossings may be difficult and you should be alert for snow bridges (which can form over creeks but may not be strong enough to support your weight). In addition, many trees may be down across trails in some years.

Be sure to check current conditions before making a plan.

May through June

Late spring into summer is a period of transition and varied conditions. Conditions for this time of year are the most difficult to predict as they depend so much on the winter snowpack and spring weather.

Even as temperatures warm and precipitation is less common, much of the Yosemite Wilderness remains wintry. Snow line is often around 7,000 feet in May to 8,000 or even 9,000 feet later in June. The higher elevations, 10,000 feet and up, usually remain snowy until mid-June or later. So, while many trails leaving Yosemite Valley, Wawona, and Hetch Hetchy are typically snow-free (until you have gone up in elevation several thousand feet), trails from Glacier Point and Tioga Roads (including Tuolumne Meadows) are still snowy (and often flooded in areas where snow has already melted). Tioga Road usually opens in late May or June; Glacier Point Road usually opens in May. Depending on the winter's snowpack, access to higher elevations may be limited until July or even later. Backpacking options remain limited through May and sometimes into June.

The Half Dome cables are normally up the Friday before the last Monday in May (Memorial Day) and come down the day after the second Monday in October, conditions permitting. (A permit is required to ascend the Half Dome cables when the cables are up.)

Creek crossings may be difficult and you should be alert for snow bridges (which can form over creeks but may not be strong enough to support your weight). In addition, many trees may be down across trails in some years until trail crews can move them.

Be sure to check current conditions before making a plan.

July through October

Summers in the Sierra are warm and dry. Yosemite receives less than five percent of its annual precipitation in summer, mostly as rain from thunderstorms. Daytime temperatures in Yosemite Valley sometimes reach 100°F (38°F) during summer, while nights are cool. Temperatures in Tuolumne Meadows (8,600 feet) in mid-summer are usually in the 70s°F (low 20s°C) in the daytime and around freezing at night. Though skies are usually clear, thunderstorms can be a daily occurrence in summer afternoons. Usually forming at higher elevations, thunderstorms form suddenly and can provide intense but brief downpours, lightning, thunder, hail, and gusty winds. Typically, by nightfall skies are clear once again.

In most years, most trails except those at the highest elevations typically have little or no snow by early July and this remains the case until we get our first significant snow, which is typically sometime in October.

The loss of snow also means less streamflow. Late in summer, smaller creeks may be completely dry. Even larger creeks may only have puddles to filter water from. The Merced and Tuolumne Rivers, along with lakes, are reliable water sources all year.

Fire activity also increases through the summer both in the park and regionally, with one to three weeks of unhealthy or worse air quality common from August through September (but possible anytime during summer and fall).

Overnight parking is prohibited on the Tioga Road (from Tuolumne Grove to Tioga Pass) and Glacier Point Road starting October 15. This includes trailhead parking lots, turnouts, and side roads. If you plan to exit the wilderness after October 15 or start a wilderness trip October 15 or later, you will need to get a ride. No public transportation is available. The earliest recent seasonal closure of Tioga Road was on October 16; if the road closes during this time, it could remain closed until late May or June.

The Half Dome cables normally come down the day after the second Monday in October, conditions permitting.

Be sure to check current conditions before making a plan.

Roads

Tioga Road (Highway 120 through the park) and the Glacier Point Road are closed by snow each winter from about early November to late May. (See a list of Tioga Road opening and closing dates since 1980.)

The Glacier Point Road is plowed to the Badger Pass Ski Area from mid December through March. The Glacier Point Road typically reopens around the end of May or early June.

Once the roads reopen, there may still be significant snow and water on trails in the area; most facilities do not open for a few weeks after the roads open.

In addition, overnight parking is prohibited on the Tioga Road and Glacier Point Road beyond Badger Pass beginning October 15 each year. Overnight parking is available at the ski area from around mid-December through March (when the ski area is open, conditions permitting).

Travelers coming to Yosemite during late fall, winter, and early spring should carry tire chains in their cars, as they may become mandatory on park roads at any time.

Current Conditions

Our current conditions page has links for current weather, road closures, trail closures, facilities closures, webcams, river flow information, and more.

For information on current snow pack conditions, visit the California Cooperative Snow Survey website. (River drainages in Yosemite are the Tuolumne and Merced Rivers, courses 157 through 180.)