Last updated: August 1, 2025
Staying informed about the UV Index is crucial for ensuring skin health in Arroio Grande, Brazil, where the subtropical climate exposes residents and visitors to varying levels of ultraviolet radiation throughout the year. Understanding UV levels helps in preventing sunburns and reducing long-term skin damage, making it essential to monitor these values, especially during peak sun hours from 11:00 AM to 3:00 PM, when the UV Index can reach levels of 4. With the region's characteristic high humidity and warm temperatures, being aware of the UV Index can empower locals and tourists alike to take protective measures and enjoy the sun safely.
The UV Index today starts low, with maximum values reaching 0 by 7:00 AM. As the sun rises, it gradually climbs to 1 at 8:00 AM and stays steady until 9:00 AM. By 10:00 AM, the index jumps to 2, marking the onset of more direct sunlight. The UV exposure peaks at 4 from 12:00 PM to 14:00 PM, signaling a critical time for sun protection. Following this peak, it dips back to 2 at 15:00 PM before easing further to 1 by 16:00 PM. Finally, the day wraps up with 0 UV exposure by 19:00 PM, making the late afternoon a much safer time for outdoor activities. Don't forget to apply sunscreen during the midday hours!
| 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 | 5 | moderate | 30 min |
| 12:00 | 6 | high | 25 min |
| 13:00 | 6 | high | 25 min |
| 14:00 | 5 | moderate | 30 min |
| 15:00 | 3 | moderate | 30 min |
| 16:00 | 2 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, UV Index levels vary significantly, with the highest values occurring in the winter months. From January to March, the UV Index consistently peaks at 14 to 12, placing these months in the extreme exposure category where unprotected skin may burn within 10 minutes. Following this, April sees a decrease to 8, categorized as very high, with a burn time of 15 minutes. By May and June, the index drops to moderate levels of 5 and 4, allowing for safer sun exposure at about 30 minutes for unprotected skin. However, as summer transitions to fall, September and October witness a rise again to 9 and 11, categorized as very high and extreme respectively, with burn times of 15 and 10 minutes. November and December return to extreme levels, mirroring the beginning of the year. Visitors and residents are strongly advised to prioritize sun protection, especially from January through March and during October and November, by wearing sunscreen, protective clothing, and seeking shade when necessary to mitigate the risks associated with high UV exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Arroio Grande | 14 | 13 | 12 | 8 | 5 | 4 | 4 | 6 | 9 | 11 | 13 | 14 |
| Rio de Janeiro UVI | 15 | 14 | 13 | 10 | 7 | 6 | 7 | 9 | 11 | 12 | 13 | 15 |
| Sao Paulo UVI | 16 | 15 | 12 | 11 | 8 | 6 | 7 | 9 | 11 | 13 | 14 | 15 |
| Belo Horizonte UVI | 17 | 16 | 14 | 12 | 9 | 7 | 8 | 10 | 12 | 13 | 14 | 16 |
| Salvador UVI | 14 | 14 | 14 | 13 | 10 | 9 | 9 | 12 | 12 | 15 | 15 | 14 |
| Fortaleza UVI | 14 | 14 | 15 | 15 | 13 | 11 | 11 | 12 | 13 | 13 | 13 | 13 |