Last updated: May 3, 2025
In Flagstaff, United States, understanding the UV Index is crucial for protecting your skin and overall health amidst its unique climate. With elevation and sun exposure prominent, the UV levels can reach alarming heights, especially during midday hours—peaking at 12, where the risk of sunburn is significantly increased. Regularly monitoring UV levels not only aids in preventing painful sunburns but also promotes long-term skin health. As Flagstaff enjoys a mild climate with sunny days, being informed about the UV Index allows residents and visitors to enjoy the outdoors safely while safeguarding their skin from harmful UV radiation.
The UV Index for the day reveals a dynamic shift in sun exposure, peaking dramatically between 11:00 AM and 1:00 PM. Starting the morning with a mild maximum of 2 at 7:00 AM, the index steadily rises, reaching 12 by midday—an indication of high risk for harm from unprotected sun exposure. As the afternoon progresses, it dips to 10 at 2:00 PM and then gradually decreases to a more moderate level of 4 by 4:00 PM. By the evening, the UV Index settles back down to 1 by 6:00 PM, signaling a safe time to enjoy the outdoors again. Be sure to protect your skin during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 6 | high | 25 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 11 | extreme | 10 min |
| 12:00 | 12 | extreme | 10 min |
| 13:00 | 12 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV Index levels fluctuate, indicating varying risks for skin exposure. The high-risk months are primarily from March to September, where the UV Index peaks at 13 in both June and July, classified as extreme, resulting in a burn time of only 10 minutes. Visitors and residents should prioritize skin protection during these months with appropriate sunscreen, protective clothing, and seeking shade during peak hours. The months of February and October also present very high UV levels of 8, with shorter burn times of 15 minutes, necessitating caution. Conversely, January, November, and December feature moderate to high UV levels, with more forgiving burn times, though protective measures should still be considered. Emphasizing sun safety year-round is essential for both health and well-being.
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 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |
| Flagstaff | 5 | 8 | 9 | 11 | 12 | 13 | 13 | 12 | 11 | 8 | 6 | 4 |