Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors of Santo Antão, Portugal, where the sun can be both a friend and a foe. As a stunning island with a Mediterranean climate, it boasts breathtaking landscapes but also poses significant UV exposure risks. Monitoring UV levels is essential for preventing sunburn and protecting skin health, particularly during peak hours when the index can reach an alarming 11. With UV intensity rising sharply from late morning through the early afternoon, awareness of these levels is key to enjoying the sun safely while exploring all that this beautiful destination has to offer.
The UV Index throughout the day reveals a dramatic rise in intensity as the sun climbs higher in the sky. Starting off gentle at 1 by 07:00, it gradually increases to 2 by 09:00. The sun's rays peak sharply at 12:00, reaching a sizzling 9, and then escalate to an intense 11 between 13:00 and 14:00. As the afternoon wanes, the index begins to decline, dipping to 8 by 16:00, and continuing to decrease, landing at 3 by 18:00 and finally 2 at 19:00. This data underscores the critical importance of sun safety during the peak hours around noon to early afternoon—be sure to protect your skin when the UV Index is at its highest!
| 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 | 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 | 10 | very high | 15 min |
| 16:00 | 8 | very high | 15 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 2 | low | 45 min |
As the seasons change, so do the UV index levels, with highest risks typically occurring from April to September. During these months, especially in June when the UV index reaches an extreme level of 11, the burn time is as short as 10 minutes. Visitors and residents should be particularly vigilant during this period, taking necessary precautions such as applying sunscreen with a high SPF, wearing protective clothing, and limiting sun exposure during peak hours. Conversely, during the winter months from January to March, the UV levels are substantially lower, categorized as moderate to high, allowing for safer outdoor activities with burn times ranging from 25 to 30 minutes. It’s crucial to remain aware of these seasonal changes to protect skin health throughout the year.
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 |
| 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 |
| Santo Antao | 3 | 5 | 7 | 9 | 10 | 11 | 10 | 10 | 9 | 7 | 4 | 3 |