Last updated: July 2, 2025
Staying informed about the UV Index is crucial for residents and visitors in Niteroi, Brazil, where the tropical climate presents unique challenges when it comes to sun exposure. Understanding UV levels is essential not only for preventing sunburn but also for protecting your skin health in the long run. With an average UV Index peaking at 7 during midday, Niteroi's sun can be intense, particularly in the summer months. By being aware of these levels, you can take necessary precautions to enjoy the beautiful beaches and outdoor activities this vibrant city has to offer while safeguarding your skin.
The UV Index reveals an early morning reprieve, starting at a gentle 1 at 7:00 AM and remaining low through 9:00 AM. However, as the sun climbs, intensity increases sharply, peaking at a 7 around noon, signaling the most potent UV exposure of the day. The early afternoon maintains a respectable UV level of 6 at 1:00 PM before gradually tapering off. By mid-afternoon, it drops to 4, then swiftly declines to 1 by 4:00 PM, and finally settles at 0 by 6:00 PM, marking the day's end for UV concern. This hourly trend underscores the importance of sun safety during peak hours, especially between 10 AM and 2 PM.
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 | 6 | high | 25 min |
12:00 | 7 | 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 |
Throughout the year, UV Index values experience significant fluctuations, with January, February, March, September, October, November, and December categorized as high-risk months due to their extreme exposure levels (UV Index 13-15) and a rapid burn time of 10 minutes. In contrast, April and August will see very high readings (UV Index 10 and 9, respectively) with a burn time of 15 minutes, while May, June, and July present a high exposure risk (UV Index 6-7) but with extended burn times of 25 minutes. To protect themselves, visitors and residents should strictly limit sun exposure during these high-risk months, seek shade whenever possible, and apply broad-spectrum sunscreen regularly, especially during peak sun hours.
UV Risk Categories
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Niteroi | 15 | 14 | 13 | 10 | 7 | 6 | 7 | 9 | 11 | 12 | 13 | 15 |
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 |