Last updated: July 2, 2025
Understanding the UV Index in Viseu, Portugal is crucial for safeguarding your skin and overall health. With the region's Csb climate, residents and visitors alike need to be aware of fluctuating UV levels throughout the day. The UV Index can spike to 10 around midday, indicating very high exposure risks that can lead to painful sunburn and long-term skin damage. By monitoring these levels, you can take proactive steps to protect yourself—shielding your skin with clothing and sunscreen during peak hours, typically from 11 AM to 3 PM. Stay informed and enjoy the beautiful sunny days in Viseu safely!
The UV Index is a dynamic measure of solar intensity throughout the day, peaking dramatically at 12:00 PM with a notable 9, reaching its zenith at 1:00 PM and 2:00 PM with a maximum value of 10. During this period, it's essential to protect your skin from harmful UV rays. Early morning hours remain quite low, peaking at just 1 by 08:00 AM, while by 10:00 AM the index climbs to 5. As the sun continues to rise, it climbs swiftly to 7 by 11:00 AM, making midday the crucial time for sunscreen and shade. As the afternoon wanes, the UV Index gradually decreases, falling back to 5 by 5:00 PM, and finally settling at 1 by 7:00 PM, signaling a safe return to outdoor activities. Stay vigilant 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 | 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 | 5 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 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 |