Last updated: July 2, 2025
In Birrwil, Switzerland, understanding the UV Index is crucial for the well-being of residents and visitors alike. As the sun’s rays can be deceptively intense, especially during peak hours from 11:00 AM to 3:00 PM when the index reaches a high of 9, staying informed about UV levels is essential for sunburn prevention and maintaining long-term skin health. With the region's temperate oceanic climate, residents face unique UV exposure risks during the warmer months, making it vital to check the UV Index regularly and take necessary precautions to enjoy the sun safely.
The UV Index reveals a dynamic day of sun exposure, peaking at 9 between 1 PM and 2 PM, indicating a notably high risk of harm from unprotected sun exposure. Early risers find the day starts with a comfortable 1 at 7 AM, gradually rising to 3 by 9 AM. By 11 AM, it reaches 7, encouraging outdoor enthusiasts to take precautions. The intensity continues to climb, soaring to its maximum at noon with an 8, before stabilizing at 9 during the early afternoon. As the sun begins its descent, the UV Index dips to 6 by 4 PM and further decreases to a 3 by 6 PM, finally settling at 1 as night falls. Enjoy the daylight, but remember to shield your skin 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 | 5 | moderate | 30 min |
| 11:00 | 7 | 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 |
During the year, UV index levels fluctuate significantly, indicating varying risks for skin damage from sun exposure. The low-risk months are January, December (UV Index 2), and November, February, October (UV Index 3), where exposure is generally safe with longer burn times of 30-45 minutes. As the season progresses into March and April (UV Index 5-6), caution is advised as burn times decrease to 25-30 minutes. The high-risk months, notably May through August (UV Index 8-9), present very high UV exposure, with burn times shortening dramatically to just 15 minutes. In September, risk lowers slightly (UV Index 6) but remains significant with a burn time of 25 minutes. Visitors and residents are strongly encouraged to protect their skin, especially during peak UV months, by wearing sunscreen, protective clothing, and seeking shade whenever possible to minimize potential harm.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Basel UVI | 2 | 3 | 5 | 6 | 8 | 9 | 9 | 8 | 6 | 4 | 2 | 1 |
| Bern UVI | 2 | 3 | 5 | 6 | 8 | 9 | 9 | 8 | 6 | 4 | 2 | 2 |
| Birrwil | 2 | 3 | 5 | 6 | 8 | 9 | 9 | 8 | 6 | 4 | 3 | 2 |
| Zurich UVI | 2 | 3 | 5 | 6 | 8 | 9 | 9 | 8 | 6 | 4 | 3 | 2 |
| Geneve UVI | 2 | 3 | 6 | 7 | 8 | 10 | 9 | 8 | 7 | 5 | 3 | 2 |
| Lausanne UVI | 2 | 4 | 6 | 7 | 8 | 10 | 9 | 9 | 7 | 5 | 3 | 2 |