Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in Viseu, Portugal, as it serves as an essential guide to sun safety. With the Mediterranean climate producing warm summers and mild winters, awareness of UV levels can significantly help in preventing sunburn and promoting healthy skin. During peak hours, particularly between 11:00 AM and 3:00 PM, the UV Index often escalates to levels as high as 10, indicating an increased risk of harm from unprotected sun exposure. Keep an eye on the UV Index to protect yourself from the sun and enjoy all that Viseu has to offer safely!
As the sun rises, the UV Index begins its gentle ascent, starting at 1 at 07:00. By 09:00, it climbs to 3, hinting at the day's potential for sun exposure. The heat peaks around 12:00, reaching a blistering 9, and hits its maximum at 13:00 and 14:00, both at a high of 10—a critical time for sun safety. As the afternoon transitions to evening, the UV Index gradually dips; by 18:00, it's down to 2, and as twilight approaches, it settles back at 1 by 19:00. Plan your outdoor activities wisely to stay safe in the sun!
| 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 | 9 | 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 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
The UV Index shows significant seasonal variation, with highest levels occurring during the summer months. From April to August, UV Index values reach their peak, particularly in June with an extreme index of 11, making it crucial for individuals to take precautions during these high-risk months. In comparison, winter months like January and December exhibit lower UV exposure, classified as moderate to low, where burn time can extend up to 45 minutes. Visitors and residents alike should be vigilant during March (UV 6) and the late spring to summer months, ensuring protection through sunscreen, clothing, and seeking shade, especially during peak hours when burn times decrease significantly.
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 |
| Porto UVI | 2 | 4 | 6 | 8 | 9 | 11 | 10 | 9 | 8 | 6 | 4 | 2 |
| Viseu | 3 | 4 | 6 | 9 | 10 | 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 |