Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Napoleon, United States, where fluctuating levels of UV radiation can significantly impact your skin health. With a Dfb climate, the region experiences warm summers that bring higher UV exposure, particularly around midday when indices can reach as high as 9. Awareness of these UV levels not only helps in preventing painful sunburns but also plays a vital role in reducing the long-term risk of skin issues. By keeping an eye on the UV Index, you can enjoy outdoor activities while protecting your skin and ensuring a healthy summer in Napoleon.
As the sun rises, the UV Index starts low at 1 from 7:00 AM and remains at this safe level until 9:00 AM. However, as the day progresses, it climbs notably, peaking at 9 between 1:00 PM and 2:00 PM, signaling a high risk of harm from unprotected sun exposure. With a maximum reading of 8 at 12:00 PM, it's crucial to take precautions. By late afternoon, specifically at 4:00 PM, the UV Index begins its descent, falling to 6, and continues to decrease to a low of 1 by 7:00 PM. As you enjoy your day, remember to protect your skin during those peak hours!
| 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 | 4 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 9 | 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 |
Throughout the year, the UV Index shows significant seasonal changes, impacting the risk of sun exposure. January and December have the lowest UV levels (2), indicating a low risk for sunburn, with burn times of 45 minutes. As spring unfolds, February and March present moderate UV levels (4-5) and shorter burn times of 30 minutes, signaling the need for increased sun protection. The high-risk months commence in April, peaking in June and July with very high UV Index values (9-10) and critical burn times of only 15 minutes; thus, it’s essential for visitors and residents to take protective measures, such as wearing sunscreen, hats, and UV-blocking clothing. August to September gradually sees a decline, but caution remains crucial with a high level of UV (7) in September and a burn time of 25 minutes. In October and November, UV levels moderate again to 4 and 5, respectively, where sun safety should continue to be a priority until levels drop back to low in December. Always consider the UV Index when planning outdoor activities, particularly during the peak summer months.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Napoleon | 2 | 4 | 5 | 9 | 9 | 10 | 10 | 9 | 7 | 5 | 4 | 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 |