Last updated: July 2, 2025
Understanding the UV Index in Chelles, France is crucial for protecting your skin and overall health. With the region's Cfb climate producing comfortably warm summers, locals and visitors alike should be aware of the varying UV levels throughout the day. This knowledge empowers you to take essential precautions against sunburn and long-term skin damage. Typically peaking around midday with an index as high as 8, Chelles presents notable UV exposure risks; thus, being informed can help you enjoy the outdoors safely and effectively.
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, the UV Index experiences significant fluctuations, with high-risk months identified primarily from April to August, where the index peaks at an alarming 9 in June. During these months, the exposure category escalates to very high, resulting in a burn time of just 15 minutes for unprotected skin. In contrast, January, November, and December have low UV levels, making sun protection less critical, with burn times extending to 45 minutes. As such, it’s essential for both visitors and residents to stay vigilant during the peak months by applying broad-spectrum sunscreen, wearing protective clothing, and seeking shade, especially between 10 AM and 4 PM, when UV rays are strongest.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chelles | 2 | 3 | 4 | 6 | 8 | 9 | 8 | 8 | 6 | 4 | 2 | 1 |
| Paris UVI | 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 |