Last updated: July 2, 2025
Understanding the UV Index is crucial for residents and visitors in Barra do Piraí, Brazil, where the subtropical Cfa climate contributes to fluctuating UV levels throughout the day. Awareness of UV levels can significantly aid in sunburn prevention and promote overall skin health, as high exposure can lead to immediate discomfort and long-term effects. During peak hours, particularly between 11:00 AM and 1:00 PM, UV Index values reach a maximum of 7, indicating a heightened risk for harmful effects on unprotected skin. With this knowledge, you can make informed choices to protect yourself against the sun's intense rays while enjoying the vibrant outdoors of this beautiful Brazilian town.
The UV Index for the day provides a clear picture of sun exposure. Starting off gently at 1 in the early hours, the intensity gradually builds, reaching a peak of 7 between 11:00 and 12:00. This is the ideal time for sun protection, as skin can burn quickly. As the afternoon progresses, the index declines, dropping to 3 by 15:00 and further down to 1 by late afternoon. After sunset, the UV Index falls to 0, indicating safe conditions. Stay sun smart, especially during the peak hours for maximum protection!
| 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 | 7 | high | 25 min |
| 13:00 | 6 | high | 25 min |
| 14:00 | 5 | moderate | 30 min |
| 15:00 | 3 | moderate | 30 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 |
The seasonal UV changes demonstrate that UV exposure remains particularly high during the first half of the year, with extreme levels peaking from January to April, where a burn can occur in as little as 10 minutes of unprotected sun exposure. High-risk months include January through April and September through November, all classified under the extreme exposure category, signaling the need for heightened sun safety measures during these times. As the year progresses into May, the UV Index drops to very high before transitioning to high levels in June and July, allowing for slightly longer burn times of 15 to 25 minutes. Visitors and residents are advised to take precautions year-round, but especially during the extreme months, by wearing sunscreen, protective clothing, and seeking shade to mitigate the risk of UV-related health issues.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 |
| Barra do Pirai | 16 | 15 | 13 | 11 | 8 | 6 | 7 | 9 | 11 | 13 | 13 | 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 |