Last updated: August 1, 2025
Understanding the UV Index is crucial for residents of Fontenay-le-Fleury and visitors alike, as it serves as a vital indicator of the sun’s intensity and potential UV radiation exposure. With France's Cfb climate, warm summers can lead to higher UV levels, particularly between midday and early afternoon. Knowing these levels not only helps in preventing sunburn but also fosters long-term skin health by minimizing the risk of skin damage and related conditions. On a typical sunny day in Fontenay-le-Fleury, UV Index values can peak at 8, highlighting the importance of taking protective measures during the brightest hours. Stay informed and enjoy the sun safely!
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 | 3 | moderate | 30 min |
| 11:00 | 5 | moderate | 30 min |
| 12:00 | 6 | high | 25 min |
| 13:00 | 7 | high | 25 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 1 | 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 |
| Fontenay-le-Fleury | 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 |