Last updated: August 1, 2025
In Sun Valley, United States, being aware of the UV Index is crucial for protecting your skin and maintaining your overall health. Understanding UV levels helps prevent sunburn and long-term skin damage, especially in this beautiful but sun-drenched climate. The UV Index reaches its peak during midday hours, with values climbing to 12—indicating an extreme risk of harm from unprotected sun exposure. With the typical Csb climate offering ample sunshine throughout the year, it's essential for residents and visitors alike to stay informed about UV levels and take necessary precautions to enjoy the outdoors safely.
Throughout the day, the UV Index displayed a dynamic pattern, peaking at an intense 12 around 1 PM. Starting off gently at 1 by 7 AM, it climbed steadily, reaching 9 by 11 AM, a clear sign to take precautions. As the sun approached its zenith, the index swelled to its maximum at 12 PM, emphasizing the importance of sun safety. Following the midday peak, the index gradually decreased, dropping to 9 by 3 PM, then tapering off further to 2 by 6 PM and 1 by 7 PM. This data underscores the significance of shielding oneself from the sun's harmful rays during the day, especially when the UV Index is at its highest.
| 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 | 8 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 5 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV Index levels vary significantly, impacting the risk of skin damage from sun exposure. January starts with a moderate UV Index of 4, where burn time is generally 30 minutes, while February sees an increase to 6, classified as high, shortening burn time to 25 minutes. The high-risk months span from March to August, peaking in May and June with an extreme UV Index of 11-12, where burn time dramatically decreases to just 10 minutes. In September, the UV Index drops to 10, still considered very high, with a burn time of 15 minutes. As the year progresses into October, it falls to 7 (high), and finally stabilizes in November and December at indices of 4 and 3, respectively (moderate), allowing for longer burn times of 30 minutes. Visitors and residents are advised to take precautions such as wearing sunscreen, protective clothing, and seeking shade, especially during high-risk months when UV exposure is at its peak.
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 |
| Sun Valley | 4 | 6 | 8 | 9 | 11 | 12 | 12 | 11 | 10 | 7 | 4 | 3 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |