Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Cerro Largo, Brazil, where the subtropical Cfa climate brings varied and often intense sun exposure. Being aware of UV levels is essential not only for preventing sunburn but also for maintaining long-term skin health. During peak hours, particularly around noon when levels can reach 5, the risk of harmful UV rays is notably higher, making it vital to take appropriate precautions. As you engage in outdoor activities, staying informed about the UV Index can help ensure you enjoy the beautiful Cerro Largo weather while protecting your skin from potential damage.
The UV Index data reveals a dynamic progression throughout the day. Starting at 0 at 7:00 AM, the intensity begins to rise slowly, reaching 1 by 8:00 AM and 9:00 AM. By 10:00 AM, it escalates to 3, indicating a moderate level of UV exposure. 11:00 AM sees the index peak at 4, and the sun reaches its zenith by noon with a UV Index of 5, marking a high risk level. The afternoon maintains this peak at 5 until 1:00 PM, before gradually declining to 4 at 2:00 PM and further down to 3 by 3:00 PM. As the sun sets, the UV radiation drops sharply, returning to 1 at 4:00 PM and 5:00 PM, and finally back to 0 from 6:00 PM onward. Awareness of these fluctuations can guide outdoor plans, ensuring protection during the peak UV hours!
| 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 | 3 | moderate | 30 min |
| 11:00 | 4 | moderate | 30 min |
| 12:00 | 5 | moderate | 30 min |
| 13:00 | 5 | moderate | 30 min |
| 14:00 | 4 | 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 reveal significant fluctuations, with the highest UV Index levels recorded from January to March, where the index hits an extreme 15, necessitating only 10 minutes for skin to start burning. As spring approaches, April sees a decrease to a very high level of 10, allowing for slightly longer exposure at 15 minutes before burning. The summer months of May to July feature a moderate UV Index ranging from 5 to 6, with burn times extending to 25-30 minutes. However, high-risk months return in August, and from September to November, where UV levels reignite to extreme and very high categories. Notably, October and November pose significant risk again with indices of 13 and 14, respectively, allowing for just 10 minutes before burn. Residents and visitors are advised to take precautions, especially during January through March and October through November, by utilizing protective clothing, sunscreen, and limiting sun exposure during these peak times to avoid skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cerro Largo | 15 | 14 | 12 | 10 | 6 | 5 | 5 | 7 | 10 | 13 | 14 | 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 |