Last updated: July 2, 2025
Understanding the UV Index is essential for residents of Lyons, United States, as it serves as a crucial indicator of the sun's ultraviolet radiation levels. Being aware of UV levels not only helps in preventing sunburn but also plays a significant role in maintaining long-term skin health. Lyons, located in a Dfb climate zone, experiences varied UV exposure risks throughout the day, with peak levels reaching a notable 9 between noon and 2 PM. By staying informed about the UV Index, you can better protect yourself from harmful rays and enjoy the beautiful outdoor environment that Lyons has to offer!
The UV Index for the day showcases a notable rise in intensity as the sun climbs higher in the sky. Starting at a low of 1 at 7:00 AM, the index gradually increases to a moderate level of 3 by 9:00 AM. However, from 10:00 AM onward, things heat up significantly, peaking at a scorching 9 from noon to 2:00 PM. As the afternoon progresses, the UV Index gradually dips back to a friendly 3 by 5:00 PM, then descends further to 1 by the time evening sets in. This pattern underscores the importance of sun protection during peak hours, especially between 11:00 AM and 2:00 PM, when UV levels are at their 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 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 7 | high | 25 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 |
As the UV Index fluctuates throughout the year, residents and visitors should be mindful of the changing sun exposure levels. During the winter months of January and December, the UV Index remains low at 2, allowing for longer safe exposure times of up to 45 minutes. However, as spring approaches, notable increases occur: March sees a rise to 6 (high exposure), while April and May escalate to 8 and 10 respectively, classified as very high, with burn times dropping to just 15 minutes. The peak UV risks are in May and June when the index reaches its highest at 10, making those months particularly hazardous for skin health. July and August maintain high levels, with UV indexes of 9, so protective measures are crucial. As summer gives way to autumn, the UV Index declines to 7 in September (high) and 5 in October (moderate), increasing the burn time. Finally, November drops back to a moderate level of 3. It is advisable for everyone to utilize appropriate sun protection during the high-risk months of April through September, particularly during peak hours, to mitigate the risk of skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Lyons | 2 | 4 | 6 | 8 | 10 | 10 | 9 | 9 | 7 | 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 |