Places / Yosemite Valley
UV index at Yosemite Valley, California
Check another placeLoading today’s UV…
- Low 0 to 2
- Moderate 3 to 5
- High 6 to 7
- Very high 8 to 10
- Extreme 11+
Hour-by-hour numbers
| Time | UV index | Level |
|---|
The next few days
Each day’s UV curve and peak, drawn on the same scale so you can compare. The forecast reaches roughly four days ahead.
What to do today
About Yosemite Valley
Yosemite Valley sits at about 4,000 feet (1,220 m), ringed by granite walls and waterfalls. Its best-known hikes, including the Mist Trail, Upper Yosemite Fall and Half Dome, climb out of the valley floor into open, bright terrain.
Elevation and your real UV
The forecast on this page covers the general area around Yosemite Valley. Weather models don’t resolve individual peaks and valleys, so treat it as the level of Yosemite Valley (about 4,000 ft). The WHO says UV rises by 10% to 12% for every 1,000 metres you climb. Using that rule of thumb:
| Place | Elevation | Compared with baseline |
|---|---|---|
| Yosemite Valley | 1,220 m (about 4,000 ft) | Baseline |
| Glacier Point | 2,199 m (7,214 ft) | about 10% to 12% more UV |
| Half Dome summit | 2,693 m (8,839 ft) | about 15% to 18% more UV |
| Tuolumne Meadows | 2,620 m (about 8,600 ft) | about 14% to 17% more UV |
Read the peak UV from the chart above, then adjust it up for where you’ll actually be. There’s a worked example in UV at altitude, on snow and under clouds.
When UV is strongest here
Summer brings long, mostly clear days and the strongest UV. The high country around Tuolumne Meadows and Glacier Point opens once the snow clears, usually in late spring or early summer. In winter and spring, snow on the ground reflects UV back up at you.
On the trail
The valley floor has patches of shade, but the switchbacks up to Yosemite Falls, granite slabs and dome summits are open and bright. On the Mist Trail the spray keeps you cool, which makes it easy to forget you’re still in strong sun.
Sun protection tips for Yosemite Valley
- Start Half Dome or Upper Yosemite Fall at dawn so you’re off the open granite before the midday peak.
- Wear a brimmed hat with a chin strap. It’s often windy on the domes.
- Cool spray doesn’t mean low UV. Reapply sunscreen after the Mist Trail.
- Bring thin gloves for the Half Dome cables. They also cover the backs of your hands.
Similar places
Related guides
- What to Wear Hiking for Sun Protection: A Practical Guide
- UV at Altitude, Snow and Clouds: Why You Burn Faster
- When Is UV Strongest During the Day? Best Times to Hike
Elevations are rounded published figures. UV forecasts are model estimates for the area and can differ from what you experience on the ground. This is general information about sun safety and isn’t medical advice. Last updated September 20, 2026.