Last updated: July 2, 2025
Understanding the UV Index is crucial for residents and visitors in Alfena, Portugal, where sunny days and mild temperatures can lead to high levels of ultraviolet radiation. With peak UV levels reaching 10 around midday, awareness of the UV Index can play a vital role in preventing sunburn and maintaining overall skin health. As part of the Csb climate zone, Alfena experiences significant UV exposure during the warmer months, making it essential to check daily UV forecasts to enjoy the outdoors safely while protecting your skin from the harmful effects of the sun. Stay informed and bask in the sun responsibly!
The UV Index peaks dramatically as the day unfolds, starting from a mild 1 at 7:00 AM and rising steadily. By 10:00 AM, it reaches 5, indicating more significant exposure risk, but it's not until 11:00 AM that it surges to 7—the sun is truly shining bright! The intensity escalates to a maximum of 10 at both 1:00 PM and 2:00 PM, marking the hours when sun protection is most crucial. As the afternoon wanes, it gradually dips, settling at 4 by 5:00 PM and returning to a safer 1 by 7:00 PM. It's essential to stay mindful of this UV trend, especially during peak hours, to protect your skin and enjoy the sunshine safely!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | 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 | 10 | very high | 15 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 8 | 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 |
As the seasons change, so do the UV levels, which significantly impact skin safety for both visitors and residents. The UV Index starts low in January (2) and December (2), indicating a low risk for sunburn. However, as we move into the spring and summer months, particularly from March (6) to August (9), the risk escalates, with April (8) and the peak in June (11) classified as extreme. The high-risk months are primarily from April through August, where burn times are notably short, especially in June, with only 10 minutes until skin damage occurs. It is crucial for individuals during these months to take necessary precautions, such as wearing sunscreen, protective clothing, and limiting sun exposure, especially during peak hours. As fall approaches, the UV Index gradually decreases, but awareness remains essential for safe outdoor activities.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Braga UVI | 2 | 4 | 6 | 8 | 9 | 11 | 10 | 9 | 8 | 6 | 4 | 2 |
| Alfena | 2 | 4 | 6 | 8 | 9 | 11 | 10 | 9 | 8 | 6 | 4 | 2 |
| Porto UVI | 2 | 4 | 6 | 8 | 9 | 11 | 10 | 9 | 8 | 6 | 4 | 2 |
| Amadora UVI | 3 | 5 | 6 | 9 | 10 | 11 | 10 | 9 | 8 | 6 | 4 | 3 |
| Lisbon UVI | 3 | 5 | 6 | 9 | 10 | 11 | 10 | 9 | 8 | 6 | 4 | 3 |
| Setubal UVI | 3 | 5 | 6 | 9 | 10 | 11 | 10 | 9 | 8 | 6 | 4 | 3 |