Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in Rio das Ostras, Brazil, where the tropical climate brings with it a range of UV exposure risks. With peak UV levels reaching as high as 8 during midday hours, awareness of these levels is vital for effective sunburn prevention and maintaining skin health. By tracking the UV Index, individuals can take proactive steps to protect themselves from harmful rays, ensuring enjoyable outdoor experiences while safeguarding against long-term skin damage. Stay informed and embrace the sun safely in this beautiful coastal paradise!
As the sun rises, the UV Index begins its climb, starting at a mild 1 at 07:00. By 08:00, it nudges up to 2, but the real surge begins as we approach midday. At 09:00, it reaches 4, and by 10:00, it hits 6—a clear sign to apply that sunscreen! The peak UV intensity occurs from 11:00 to 12:00, where it soars to an impressive 8, making it crucial to seek shade and wear protective clothing. As the afternoon rolls in, the index gradually decreases—7 at 13:00, 5 at 14:00, before plunging to 2 by 15:00. Finally, from 16:00 to 19:00, the UV Index dwindles down to 1 and finally 0, marking the end of a day where sun safety was paramount during those peak hours. Stay vigilant under the sun!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 7 | high | 25 min |
| 14:00 | 5 | 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, seasonal UV changes exhibit significant fluctuations, particularly peaking during the winter months (January to April) with an extreme UV Index ranging from 11 to 16 and a burn time of just 10 minutes. The high-risk months are notably concentrated in the winter and early spring, where the UV Index remains extreme, suggesting that visitors and residents should take extra precautions by seeking shade and wearing protective clothing. As we transition into late spring and summer, the UV Index decreases to a very high and high level, allowing for slightly longer safe exposure times of 15 to 25 minutes. However, even during these months (May to August), it is crucial to maintain vigilance, especially in September and October, as UV levels rebound to extreme levels again. To stay safe, individuals are advised to consistently check the UV Index and employ sun protection strategies year-round, especially during peak UV times.
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 |
| Rio das Ostras | 16 | 15 | 13 | 11 | 8 | 6 | 7 | 9 | 12 | 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 |