Last updated: July 2, 2025
In Sergeant Bluff, United States, staying informed about the UV Index is crucial for maintaining skin health and preventing sunburn. Understanding the daily UV levels allows residents to take appropriate precautions during the sunniest hours, especially since the area experiences a Dfa climate that can lead to varying levels of UV exposure throughout the year. Notably, during peak daylight, such as from noon to 2 PM, UV Index levels soar to a significant 10, underscoring the importance of sunscreen and protective clothing. By keeping a close eye on the UV Index, you can enjoy the outdoors while safeguarding your skin from harmful radiation.
As the sun rises, the UV Index begins its gentle ascent, starting at 1 at 07:00. By 09:00, it climbs to 3, hinting at the day's potential for sun exposure. The heat peaks around 12:00, reaching a blistering 9, and hits its maximum at 13:00 and 14:00, both at a high of 10—a critical time for sun safety. As the afternoon transitions to evening, the UV Index gradually dips; by 18:00, it's down to 2, and as twilight approaches, it settles back at 1 by 19:00. Plan your outdoor activities wisely to stay safe in the sun!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
The UV Index experiences significant seasonal changes, with high-risk months typically from April to September when the levels elevate to very high and extreme categories. Notably, June peaks at a UV Index of 11, indicating an extreme risk of harm from unprotected sun exposure, with a burn time of just 10 minutes. May and July follow closely behind, both maintaining UV indexes of 9 and 10. Visitors and residents are strongly advised to take precautions during these months, including seeking shade, wearing protective clothing, and applying sunscreen regularly to mitigate UV exposure. In contrast, from October to March, the UV Index drops to moderate or low levels, with burn times increasing to 30 to 45 minutes, making sun protection less critical during this period.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sergeant Bluff | 3 | 5 | 5 | 8 | 9 | 11 | 10 | 9 | 8 | 5 | 3 | 2 |
| 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 |