Last updated: July 2, 2025
Understanding the UV Index in Lousa, Portugal is crucial for safeguarding your skin against harmful ultraviolet radiation. With extensive exposure to the sun, especially during those peak midday hours when the UV Index can soar to a striking 10, it's essential to be aware of these levels to prevent sunburn and maintain overall skin health. Lousa's mild Mediterranean climate, characterized by warm summers and ample sunshine, can intensify UV risks, making awareness even more vital. Whether you're enjoying outdoor activities or simply soaking in the beautiful surroundings, keeping an eye on the UV Index is your best defense against the sun's potentially damaging effects.
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 |
As the seasons change, so too does the UV Index and the associated risk of sunburn. From January to February, the UV Index remains moderate (3-4) with a burn time of 30 minutes. However, in March, it escalates to high (6), reducing burn time to 25 minutes, signaling the start of increased caution. April and May are particularly high-risk months with very high indices (8-9) and short burn times of just 15 minutes. The intensity peaks in June at an extreme level (11), where unprotected skin can burn in as little as 10 minutes. July and August follow closely with very high indices (9-10) and continued caution advised. A gradual decline starts in September (UV 8) and continues through October, where the risk decreases to high (6) before settling back to moderate in the late fall (November and December, UV 3-4). Residents and visitors are strongly advised to wear sun protection during high-risk months, especially from March through September, to reduce the risk of harmful UV exposure.
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 |
| Lousa | 3 | 4 | 6 | 8 | 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 |