Last updated: July 2, 2025
Understanding the UV Index in Mountain View, United States is crucial for safeguarding your skin and overall health. With the region's Dfb climate, residents and visitors alike are exposed to varying UV levels throughout the day, peaking between late morning and early afternoon. The UV Index reaching as high as 12 means that even a short stroll outside can lead to sunburn if precautions aren’t taken. Being aware of UV levels helps in planning outdoor activities and reinforces the importance of sun safety, allowing you to enjoy Mountain View's sunny days while protecting your skin from potential damage.
The UV Index throughout the day presents a fascinating journey of sun intensity. Beginning with a gentle rise, the index starts at a mere 1 at 07:00. As the morning unfolds, it climbs steadily, reaching 3 by 09:00. The sun's power peaks dramatically at 12:00, hitting a blistering 11, just before hitting its apex of 12 at 13:00. After this zenith, the intensity begins to wane, descending to 10 by 15:00 and gradually tapering off to 5 by 17:00. The evening sees a return to softer sunlight, with the index dropping back to 1 by 19:00. Be sure to protect yourself during those peak hours when the sun fires up the scale!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 9 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 12 | extreme | 10 min |
| 14:00 | 12 | extreme | 10 min |
| 15:00 | 10 | very high | 15 min |
| 16:00 | 8 | very high | 15 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, the UV Index exhibits significant seasonal variations, peaking during the summer months of May to August, where it reaches extremes of 11 to 12. The highest risk occurs in May, June, and July, with burn times as short as 10 minutes under these conditions. March and April also present considerable UV exposure, categorized as very high, with burn times of just 15 minutes. Visitors and residents should exercise caution from late winter through summer, especially during these high-risk months, by seeking shade, wearing protective clothing, and applying broad-spectrum sunscreen regularly to minimize the risk of skin damage. As the season transitions into fall and winter, UV levels decrease, offering more moderate exposure from October to December.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chicago UVI | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 8 | 6 | 4 | 2 |
| Brooklyn UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| New York City UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Mountain View | 4 | 6 | 8 | 10 | 11 | 12 | 12 | 11 | 10 | 7 | 5 | 3 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |