Last updated: July 2, 2025
In Sao Mateus, Brazil, understanding the UV Index is crucial for protecting your skin and overall health. The UV Index measures the strength of ultraviolet radiation from the sun, which can lead to sunburn and long-term skin damage if proper precautions aren't taken. With a tropical climate characterized by high UV exposure, especially during peak hours between 10 AM and 2 PM, awareness of these levels can significantly reduce the risk of harmful effects. Knowing when the UV Index peaks—reaching as high as 8—empowers residents and visitors to make informed decisions about sun protection, ensuring a safer and more enjoyable experience in sunny Sao Mateus.
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 |
During the year, UV index levels show significant variation, with January to April consistently experiencing extreme levels (UV Index 15-12) and minimal safe exposure times of just 10 minutes, indicating high-risk months for skin damage. This trend continues with a notable increase in November and December, which also see extreme UV conditions. May marks a shift to very high exposure (UV Index 9) with a slightly extended burn time of 15 minutes. Throughout the summer months, June to August, UV levels remain high to very high (UV Index 7-10), allowing for longer safe exposure times of up to 25 minutes in June before returning to 15 minutes in July and August. September and October then revert to extreme conditions (UV Index 12-14) with a reduced burn time of 10 minutes. Given these fluctuations, it is crucial for visitors and residents to adopt protective measures—such as wearing sunscreen, protective clothing, and seeking shade—particularly during the high-risk months of January to April and September to November.
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 |
| Sao Mateus | 15 | 15 | 13 | 12 | 9 | 7 | 8 | 10 | 12 | 14 | 15 | 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 |