Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in Cachoeiras de Macacu, Brazil, where the tropical climate brings with it an increased risk of sun exposure. With UV levels typically peaking around midday, it’s essential to monitor these values to protect yourself from sunburn and long-term skin damage. On sunny days, the UV Index can reach highs of 8, indicating a very high risk of harm from unprotected sun exposure. By staying informed about UV Index levels, you can enjoy the beautiful outdoors of Cachoeiras de Macacu while safeguarding your skin health and well-being.
As the sun rises, the UV Index begins its ascent, starting at a gentle 1 by 7:00 AM. By 8:00 AM, it nudges up to 2, signaling a mild increase in UV exposure. The intensity heats up quickly, reaching a moderate 4 by 9:00 AM, before hitting its peak of 8 from 11:00 AM to 12:00 PM. This is the prime time for sun safety awareness! After noon, the UV Index gradually declines; by 3:00 PM, it recedes to 3, and as the day wanes, it drops significantly to 1 by 4:00 PM. By evening, UV levels have diminished, reaching 0 by 6:00 PM, offering a reprieve from the sun’s rays.
| 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 | 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 experiences substantial fluctuations, with high-risk months typically being from January to April, as well as September to November, where the index peaks at 16 in January and December, indicating extreme exposure levels with a burn time of just 10 minutes. Visitors and residents should take caution during these months, particularly from mid-winter through spring, and again in the fall. The transition into late spring and early summer sees a significant drop, with the UV Index ranging from 6 to 9, classifying it as high to very high with slightly longer burn times of 15 to 25 minutes. It is vital for everyone to remain vigilant about sun protection year-round, wearing appropriate clothing, applying sunscreen, and seeking shade, especially during peak UV hours in the high-risk months.
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 |
| Cachoeiras de Macacu | 16 | 15 | 14 | 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 |