Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Hennef, Germany, as it provides essential information about the sun's strength and potential risks associated with UV exposure. Recognizing UV levels helps in preventing sunburn and maintaining skin health, making it an important aspect of outdoor activities, especially during the warmer months. With Hennef’s Cfb climate, characterized by mild summers and moderate sunshine, it's vital to be aware of the UV Index—particularly as levels peak between 12:00 PM and 2:00 PM, reaching up to 8. Being informed allows residents to protect themselves and enjoy the sun safely, reducing the risk of harmful effects associated with overexposure.
Starting the day with a gentle UV Index of 1 at 7:00 AM, the sun gradually climbs higher. By 10:00 AM, the index reaches 5, signaling a noticeable increase in sunlight intensity. The peak UV Index occurs between 12:00 PM and 2:00 PM, soaring to 8, emphasizing the need for sun protection during these hours. As the afternoon unfolds, the index slightly dips, dropping to 6 by 4:00 PM, and further declining to 3 by 6:00 PM. As daylight fades, the UV Index returns to 1 by 7:00 PM, marking the end of a day bathed in sunshine. Remember to stay safe in the sun 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 | 6 | high | 25 min |
| 12:00 | 8 | very high | 15 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 | 3 | moderate | 30 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 |
| Hennef | 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 |