Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors in Ascona, Switzerland, a picturesque town known for its stunning lakeside views and sunny climate. With UV levels reaching a peak of 10 during midday hours, being aware of these fluctuations is essential for preventing sunburn and maintaining overall skin health. Ascona’s climate, classified as Dfc, brings both delightful warmth and elevated UV exposure risks, especially in the summer months. Staying informed about the UV Index helps you enjoy the outdoors safely while protecting your skin from harmful effects.
At dawn, the UV Index begins its climb, starting at a mild 1 at 07:00. As the sun rises higher, it steadily ascends, reaching 2 by 08:00 and escalating to 3 by 09:00. The peak of the day arrives at noon with a striking 9, just before it hits its maximum of 10 from 13:00 to 14:00, signifying a need for sun protection. The intensity begins to taper off after that, dropping to 9 at 15:00, then descending through 7 at 16:00, and winding down to 4 by 17:00. As evening approaches, the UV Index dwindles to 3 by 18:00 and finally returns to 1 by 19:00, illustrating the clear and powerful influence of the sun throughout the day.
| 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 | 8 | very high | 15 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 9 | very high | 15 min |
| 16:00 | 7 | 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 shows significant seasonal variations, indicating changes in the sun's intensity. January and December have the lowest UV levels (2), categorized as low exposure, allowing for longer burn times of up to 45 minutes. However, as we transition into February and March, the index rises to moderate (4) and high (6) categories, respectively, with reduced burn times of 30 and 25 minutes. The most critical months for sun exposure are from April to August, where the UV Index reaches its peak at 10 during June and July, classified as very high exposure with a rapid burn time of just 15 minutes. The UV levels then gradually decrease in September to high (7) and back to moderate levels in October and November. Visitors and residents are advised to take extra precautions during the high-risk months of April to August, by wearing protective clothing, applying sunscreen frequently, and minimizing sun exposure during peak hours.
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 |
| 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 |
| Ascona | 2 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 7 | 5 | 3 | 2 |