Last updated: June 2, 2025
Understanding the UV Index is essential for residents and visitors of Sao Martinho do Porto, Portugal, where beautiful coastal scenery meets a temperate climate. Being aware of UV levels helps you take proactive steps in sunburn prevention and maintaining long-term skin health. With peak UV exposure reaching a striking 11 during midday hours in the sun-drenched summer months, it’s crucial to stay informed about these levels to protect your skin. The mild climate of Sao Martinho do Porto, classified as Csb, features significant UV risks, especially between 11 AM and 2 PM, making it vital to check the UV Index regularly for a safe, enjoyable time outdoors.
The UV Index throughout the day showcases an intriguing pattern of intensity. Starting low at 07:00 and 08:00, with a manageable score of 1, the sun's rays gradually intensify. By 09:00, the index climbs to 3, hinting at a warmer day ahead. The peak arrives at noon, hitting a striking 9, and just a little later, the UVI reaches its zenith at 13:00 and 14:00, both at an impressive 11. As the afternoon progresses, the UV exposure starts to wane, dipping to 9 at 15:00 and further decreasing to 5 by 17:00. The evening cools down significantly, with the index returning to the comfortable levels of 3 at 18:00 and finally resting at 1 by 19:00. Stay protected and enjoy the sun, especially during those peak hours!
| 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 | 11 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 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 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 |
| Sao Martinho do Porto | 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 |