Last updated: August 1, 2025
Understanding the UV Index in Herval, Brazil is essential for anyone looking to protect their skin and health under the sun. With the region's Cfa climate, which features warm summers and mild winters, the UV levels can significantly affect your well-being, especially during peak hours. Being aware of the UV Index helps in preventing sunburn and reducing long-term skin damage, allowing you to enjoy outdoor activities safely. Typically reaching a maximum of 4 around midday, it's crucial to plan ahead and take protective measures on days with higher exposure risks, ensuring your sun-filled adventures remain fun and safe!
The UV Index throughout the day clearly illustrates its early morning calm before reaching the peak around midday. Starting at a maximum of 0 at 07:00, the index gradually rises to 1 by 08:00 and remains slight until it hits 2 at 10:00. The real intensity is felt between 11:00 and 13:00, where it peaks at 4, emphasizing the importance of sun protection during these hours. As the afternoon unfolds, the index steadily declines, dropping back to 2 by 15:00 before tapering off to 1 at 16:00 and returning to 0 by 18:00. Overall, this data underscores the significant variation of UV exposure throughout the day, encouraging us to be mindful of sun safety during its highest points.
| 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 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Herval | 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 |