Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Herval, Brazil, as it highlights the daily risks from ultraviolet radiation. Awareness of UV levels is vital for preventing sunburn and maintaining long-term skin health. In Herval, a humid subtropical climate (Cfa), the sun’s rays can be particularly intense during midday, peaking with a UV Index of 4 around noon. This means that even on seemingly mild days, it's essential to protect your skin to minimize exposure to harmful UV radiation. Stay informed and safe to enjoy the beautiful Brazilian sunshine responsibly!
The UV Index throughout the day reveals a dynamic pattern of sun intensity. In the morning, it starts off low, peaking at 1 by 09:00. As the sun climbs higher, we see a steady increase with the index reaching 3 by 11:00. The highest point occurs from 12:00 to 13:00, where the UV Index hits a robust 4, indicating a need for sun protection during those hours. Following this peak, the index gradually declines, returning to 2 at 15:00, and then dropping back down to 0 by 18:00, marking the end of significant UV exposure for the day. Plan your outdoor activities accordingly to stay safe under the sun!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 0 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 1 | low | 45 min |
| 10:00 | 2 | low | 45 min |
| 11:00 | 3 | moderate | 30 min |
| 12:00 | 4 | moderate | 30 min |
| 13:00 | 4 | moderate | 30 min |
| 14:00 | 3 | moderate | 30 min |
| 15:00 | 2 | low | 45 min |
| 16:00 | 1 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 0 | 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 |