Last updated: July 2, 2025
Understanding the UV Index in Altena, Germany is essential for everyone looking to enjoy the outdoors safely. The UV levels in Altena can reach a maximum of 8 during the peak hours of midday, making it crucial to be aware of the potential for sunburn and the long-term effects on skin health. With a Cfb climate that offers plenty of cloudy days yet still exposes residents to significant UV radiation, knowing how to protect yourself from harmful rays can help ensure your outdoor activities are both enjoyable and safe. Stay informed and keep your skin protected!
The UV Index throughout the day reveals a distinct pattern of increasing intensity as the sun rises. At 07:00, the index starts at a mild 1, gradually climbing to 2 by 08:00. As the day progresses, the intensity ramps up, peaking at an impressive 8 during the hours of 13:00 and 14:00—a clear indication that midday sun is at its most potent. After this height, the index begins to descend, dropping back to 6 at 16:00, and later settling at a more manageable 1 by 19:00. This hourly data clearly underscores the importance of sun protection during the midday hour for outdoor activities.
| 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 | 7 | high | 25 min |
| 13:00 | 8 | very high | 15 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 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV Index values fluctuate significantly, indicating varying levels of sun exposure risk. The high-risk months are from May to August, where the UV Index reaches its peak at 7-8, classifying them as high to very high exposure. Specifically, June and July present the greatest risk, with a burn time of only 15 minutes. In contrast, the winter months (January, February, November, and December) show a low exposure category with UV Index values of 1-2, allowing for longer safe sun exposure (up to 45 minutes). To ensure safety, it is advisable for visitors and residents to take protective measures during the high UV months, such as wearing sunscreen, protective clothing, and seeking shade, especially during midday hours.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hamburg UVI | 1 | 2 | 3 | 5 | 7 | 8 | 7 | 7 | 5 | 3 | 2 | 1 |
| Berlin UVI | 1 | 2 | 4 | 5 | 7 | 8 | 7 | 7 | 5 | 3 | 2 | 1 |
| Koeln UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 4 | 2 | 1 |
| Altena | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 4 | 2 | 1 |
| Frankfurt am Main UVI | 2 | 3 | 4 | 5 | 8 | 8 | 8 | 7 | 5 | 4 | 2 | 1 |
| Munich UVI | 2 | 3 | 5 | 6 | 8 | 9 | 9 | 8 | 6 | 4 | 2 | 1 |