Last updated: July 2, 2025
Understanding the UV Index is crucial for residents and visitors of Les Clayes-sous-Bois, France, as it plays a vital role in preventing sunburn and promoting skin health. With a climate classified as Cfb, the area experiences varied UV exposure throughout the day, peaking around noon to mid-afternoon when levels can soar to 8. This makes it essential to stay informed about UV levels, especially during the hotter months, to protect yourself from harmful rays and enjoy the beautiful French outdoors safely. So, whether you’re lounging in a park or strolling through the charming streets, keep an eye on the UV Index to ensure your skin stays healthy and sunburn-free!
As the day begins, the UV Index stays low, peaking at 1 during the early hours from 07:00 to 08:00. However, as the sun rises higher, the intensity of ultraviolet radiation climbs sharply. By 10:00, it reaches 4, and by midday, it escalates to an impressive 7. The afternoon is marked by the highest levels between 13:00 and 15:00, where the UV Index soars to 8—a potent reminder of the sun's power. As the sun begins to dip, the UV levels gradually decline, settling at 5 by 17:00 and tapering off to 2 by 19:00. This hourly data highlights the importance of sun protection during peak hours, especially from 11:00 to 15:00, when UV exposure is at its highest.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 5 | moderate | 30 min |
| 12:00 | 7 | high | 25 min |
| 13:00 | 8 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 2 | low | 45 min |
Throughout the year, UV levels vary significantly, with the highest risk months occurring from May to August, where the UV Index reaches a peak of 9 in June and remains at 8 during July and August, indicating a very high exposure category and a critical burn time of just 15 minutes. In contrast, winter months see much lower UV levels, with January and November registering a UV Index of 2 and December dropping to 1, categorized as low exposure. Visitors and residents should exercise caution during the high-risk months by minimizing sun exposure, wearing protective clothing, and applying sunscreen regularly, particularly between late spring and early fall when UV radiation is at its strongest.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Paris UVI | 2 | 3 | 5 | 6 | 8 | 9 | 8 | 8 | 6 | 4 | 2 | 1 |
| Les Clayes-sous-Bois | 2 | 3 | 5 | 6 | 8 | 9 | 8 | 8 | 6 | 4 | 2 | 1 |
| Lyon UVI | 2 | 3 | 5 | 6 | 8 | 10 | 9 | 8 | 6 | 5 | 3 | 2 |
| Nice UVI | 2 | 4 | 6 | 7 | 8 | 10 | 9 | 8 | 7 | 5 | 3 | 2 |
| Marseille UVI | 2 | 4 | 5 | 7 | 9 | 10 | 9 | 8 | 7 | 5 | 3 | 2 |
| Toulouse UVI | 2 | 4 | 6 | 7 | 9 | 10 | 10 | 9 | 7 | 5 | 3 | 2 |