Last updated: June 2, 2025
In Franco da Rocha, Brazil, understanding the UV Index is crucial for protecting your skin and overall health. High UV levels can lead to sunburn and increase the risk of skin cancer, making it essential to stay informed about daily UV exposure, especially during peak hours. With a Cfa climate characterized by warm and humid summers, residents and visitors alike should be aware of the typical risks associated with UV radiation throughout the day. From a moderate index of 2 at 9 AM to a peak of 6 around noon, knowing when to seek shade or apply sunscreen can make a significant difference in maintaining skin health while enjoying the outdoors.
The UV Index throughout the day presents an interesting fluctuation, starting off quite low with a maximum of 1 at both 07:00 and 08:00. As the sun rises higher, the intensity increases sharply, peaking at 6 from 11:00 to 13:00. This is the critical time to protect your skin, as a UV Index of 6 indicates a moderate risk of harm from unprotected sun exposure. The afternoon sees a gradual decline, with numbers dropping back to 2 by 15:00 and returning to 1 by 16:00 and 17:00. Finally, as the day comes to a close, the UV Index falls to 0 by 18:00 and remains there through the evening, reminding us that while the sun's rays can be strong during the day, they also retreat as the sun sets.
| 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 | 6 | high | 25 min |
| 12:00 | 6 | high | 25 min |
| 13:00 | 6 | high | 25 min |
| 14:00 | 4 | 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 |
The UV Index exhibits significant seasonal fluctuations, with the highest levels consistently occurring in the winter months of January and February, where both register at 16, categorizing exposure as extreme and necessitating a mere 10 minutes of sun exposure before burning. Following closely, March through April also showcases extreme UV levels, before tapering slightly in May, where the index drops to 8 but remains in the very high range. June and July see mild reductions, landing at 6 and 7, respectively, representing high exposure risks with a burn time of 25 minutes. Nevertheless, as the season transitions back to fall, September and October return to extreme levels, particularly notable in September at 11 and October at 13, while November maintains a high index of 14. Visitors and residents should remain vigilant from January through April and again in September and October, as these are critical months for high UV exposure risks. It's advisable for everyone to adopt protective measures, including wearing sunscreen and protective clothing, during these high-risk periods to minimize adverse effects from UV exposure.
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 |
| Franco da Rocha | 16 | 16 | 13 | 11 | 8 | 6 | 7 | 9 | 11 | 13 | 14 | 16 |
| 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 |