Last updated: July 2, 2025
In Saint-Louis, France, being aware of the UV Index is crucial for protecting your skin and overall health. Understanding UV levels helps you prevent sunburn and long-term skin damage, allowing you to enjoy the sun safely. With its Cfb climate characterized by mild summers, residents and visitors alike face varying UV exposure throughout the day, especially during peak hours when levels can soar to 9. By staying informed about the UV Index, you can make smart choices about sun protection and keep your skin healthy under the vibrant summer sun.
As the day unfolds, the UV Index rises to its peak, painting a vivid picture of sun intensity. At 7:00 AM, the index starts modestly at 1, making for a gentle morning. By 8:00 AM, we see a slight increase to 2, perfect for a stroll. The sun gains strength, reaching 3 by 9:00 AM and hitting 4 at 10:00 AM. It’s 11:00 AM when things heat up with a 6, leading into the midday sun, where the UV Index surges to a striking 8 at 12:00 PM. The peak occurs at 1:00 PM, with a sizzling 9, holding steady until 2:00 PM. As the afternoon progresses, the index dips gradually, dropping to 8 at 3:00 PM, then further to 6 by 4:00 PM. By 5:00 PM, it eases to 4, followed by a gentle descent to 3 at 6:00 PM. As the sun sets, the index softens to 1 by 7:00 PM, bidding farewell to a day of vibrant sun exposure. Remember to stay protected during those peak hours!
| 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 | 4 | moderate | 30 min |
| 11:00 | 6 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 8 | very high | 15 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, the UV Index demonstrates notable seasonal variations that affect exposure risk. January and February have relatively low to moderate UV levels (Index 2-3), with safe burn times of 45 and 30 minutes respectively. As spring approaches, March sees a rise to an index of 5, and by April, it reaches 6, marking the beginning of high-risk months. The most critical period arrives in May and June, where the UV Index peaks at 8-9, indicating very high exposure risk and a reduced burn time of just 15 minutes. July and August maintain this peak, before tapering off in September with a return to a high risk (UV Index 6). October brings a moderate reduction (Index 4), while winter months November and December drop back to low levels. Visitors and residents should be particularly vigilant during May through September, using sunscreen and protective clothing to minimize harmful effects during these high-risk months.
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 |
| Saint-Louis | 2 | 3 | 5 | 6 | 8 | 9 | 9 | 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 |