Last updated: July 2, 2025
Understanding the UV Index is crucial for residents and visitors in Rio Negrinho, Brazil, where the subtropical Cfa climate brings unique sun exposure challenges. With midday UV levels peaking at 6, the risk of sunburn and long-term skin damage is significant, highlighting the importance of awareness and protection. By keeping an eye on local UV levels, you can take proactive steps to safeguard your skin health while enjoying the outdoors in this beautiful region. Whether lounging in the sun or participating in outdoor activities, being informed about UV risks is essential to help you stay safe and healthy all year round.
Throughout the day, the UV Index escalates to its peak between 12:00 PM and 1:00 PM, reaching a high of 6—a clear indicator to stay protected from the sun's rays. Early morning hours see a gentle start, with a maximum 1 at 7:00 AM and 8:00 AM, gradually rising to 2 by 9:00 AM. As the sun climbs, so does the intensity, spiking to 5 at 11:00 AM and maintaining a steady 6 for the peak hours. Following this brief burst of intensity, the UV Index dwindles swiftly, dropping to 4 by 2:00 PM, then further decreasing to 3 at 3:00 PM, and tapering off to 1 by 4:00 PM. Finally, as daylight fades, the index plummets to 0 by 6:00 PM, marking the end of a vibrant, sunlit day. Remember to stay safe and protect your skin, especially during midday hours!
| 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 | 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 |
Throughout the year, the UV Index in our region exhibits significant seasonal variations, with the highest risk months occurring from January to April, where the UV Index consistently reaches extreme levels between 15 and 13 and the burn time is merely 10 minutes. As we transition into May through July, the UV Index decreases slightly to 7 and 6, categorized as high, allowing for a longer burn time of 25 minutes. However, August experiences a spike again to 8, deemed very high, with a burn time of 15 minutes. In September and October, the UV levels rise back to extremes at 11 and 13, leading into the winter months of November and December, which again reflect extreme UV levels of 15. Visitors and residents should take preventive measures, such as wearing sunscreen, protective clothing, and sunglasses during the high-risk months, especially from January to April, and remain vigilant even in the late summer and early autumn, ensuring safe sun exposure throughout the year.
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 |
| Rio Negrinho | 15 | 15 | 13 | 11 | 7 | 6 | 6 | 8 | 11 | 13 | 15 | 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 |