Last updated: August 1, 2025
In Marinha Grande, Portugal, staying informed about the UV Index is essential for protecting your skin and overall health. As a popular destination known for its beautiful coastline and sunny climate, understanding UV levels helps residents and visitors alike avoid harmful sunburns and long-term skin damage. With UV Index readings soaring as high as 10 during midday, there are significant risks of overexposure, particularly in the warm months. Being aware of the UV Index not only enhances your outdoor experience but ensures you enjoy the sun safely.
The UV Index throughout the day presents a dynamic portrait of solar intensity. Early morning hours from 7:00 to 8:00 maintain a gentle glow with a consistent level of 1, suggesting low sun exposure risk. As the day progresses, a noticeable shift occurs; by 9:00, the index climbs to 3, marking the onset of stronger rays. The peak is reached at 1:00 PM and 2:00 PM, where the UV Index soars to an intense 10, indicating very high exposure risk, making sun protection vital. Post-peak, from 3:00 PM onward, the index gradually declines, settling to 5 by 5:00 PM and dwindling further to low levels of 1 by 7:00 PM. This data underscores the importance of being sun-smart during those midday hours when UV radiation is strongest.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 6 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 9 | 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 varies significantly throughout the year, with notable increases during the warmer months. High-risk months include April through September, when the UV Index reaches its peak, particularly in June at an extreme level of 11. During these months, the burn time shortens dramatically, with a maximum exposure of just 10 minutes in June to avoid skin damage. Conversely, the winter months of January, February, November, and December exhibit a moderate risk, allowing for longer exposure times of 30 minutes. Visitors and residents are advised to take precautions during the high-risk period, including wearing sunscreen, protective clothing, and limiting sun exposure, especially between the hours of 10 AM and 4 PM when UV radiation is the strongest.
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 |
| Marinha Grande | 3 | 5 | 6 | 9 | 9 | 11 | 10 | 9 | 8 | 6 | 4 | 3 |
| 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 |