Last updated: July 2, 2025
In Lewisville, United States, awareness of the UV Index is crucial for safeguarding your skin health and preventing sunburn. Understanding the UV levels throughout the day helps you take proactive measures against harmful UV radiation, especially during the peak hours between 10 AM and 2 PM when the index can soar as high as 11. With Lewisville's Cfa climate, which experiences warm summers and mild winters, residents and visitors alike face notable UV exposure risks. By staying informed about the UV Index, you can enjoy the outdoors while prioritizing your skin's wellbeing.
The UV Index for the day showcases a dramatic rise in intensity as the sun climbs higher in the sky. Starting from a mild 1 at 07:00, it escalates steadily to a peak of 11 between 13:00 and 14:00, making it crucial to prioritize sun safety during these hours. As noon approaches, protective measures become essential with the index hitting a striking 10 at 12:00. Following that, a gradual decline occurs, retreating to 6 at 16:00, then tapering to 2 by 18:00 and settling back to 1 by 19:00. This pattern emphasizes the importance of seeking shade and wearing sunscreen during the midday hours when UV exposure 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 | 5 | moderate | 30 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 min |
| 15:00 | 9 | 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 experiences significant fluctuations, with the highest values occurring from April to August, where levels reach 11 to 12 and are categorized as extreme. This indicates a burn time of only 10 minutes during these peak months. Visitors and residents should be particularly cautious during these high-risk months, as exposure can lead to serious skin damage. March and September also present elevated risks with indices of 8 and 10, respectively, categorized as very high. It's advisable for everyone to take protective measures, such as wearing sunscreen, hats, and protective clothing, especially during midday hours when UV radiation is most intense. In comparison, the months of January, December, and November see lower UV indices (ranging from 4 to 6), where the burn time increases to 25-30 minutes, though sun protection is still recommended.
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 |
| Lewisville | 4 | 7 | 8 | 11 | 11 | 12 | 11 | 11 | 10 | 8 | 6 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |