Last updated: July 2, 2025
Understanding the UV Index is essential for residents of Vista West, United States, where the sunny BSk climate brings both warmth and increased exposure to ultraviolet radiation. Being aware of UV levels is crucial not only for preventing sunburn but also for maintaining long-term skin health. With peak UV Index values soaring as high as 12 during midday hours, it's vital to take protective measures to avoid harmful effects. By keeping track of the UV Index, you can enjoy the sun safely while protecting your skin from potential damage.
As the sun rises, the UV Index (UVI) steadily climbs, beginning with a safe level of 1 at 07:00. By 09:00, it reaches 4, signaling a stronger need for sun protection. The peak intensity occurs between 12:00 and 13:00, where the UVI hits an alarming 12, illustrating the importance of taking precautions during these hours. As the afternoon wanes, values start to recede, dropping to 9 at 15:00 and further declining to 2 by 18:00. Wrap up your outdoor activities as the sun dips below the horizon, as the UVI falls back to 1 by 19:00. Always remember to stay safe under the sun, especially during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | 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 | 11 | extreme | 10 min |
| 15:00 | 9 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
As the seasons change, so do the UV Index levels, impacting sun exposure and burn times significantly. January begins with a moderate UV Index of 4 and a burn time of 30 minutes, but by April, the index escalates to an extreme level of 11, drastically reducing burn time to just 10 minutes. The highest risk months are June and July, featuring an extreme UV Index of 12 and a minimal burn time of 10 minutes, highlighting the need for caution. As summer transitions to fall, the UV Index begins to decline, with September at 9 (very high) and October back to 6 (high). November and December see moderate levels again with indices of 4 and 3 respectively, allowing for longer burn times of 30 minutes. It is essential for visitors and residents to remain vigilant during high-risk months (April through September), utilizing sunscreen, protective clothing, and limiting sun exposure during peak hours to ensure safety while enjoying the outdoors.
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 |
| Vista West | 4 | 6 | 7 | 11 | 10 | 12 | 12 | 11 | 9 | 6 | 4 | 3 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |