Last updated: August 1, 2025
Understanding the UV Index in Biritiba Mirim, Brazil, is essential for safeguarding your skin health and preventing sunburn. This vibrant region experiences a Cfa climate, characterized by warm summers, which can lead to increased UV exposure, particularly during midday hours. From 10 AM to 2 PM, UV levels often peak, hitting a maximum of 7, making it crucial to be aware of these fluctuations. By staying informed about UV levels, residents and visitors can take effective precautions, ensuring a safer and healthier outdoor experience in the beautiful landscapes of Biritiba Mirim.
At dawn, the UV Index starts off low, with a maximum of 1 at 07:00 and 08:00. As the sun rises higher, it reaches 3 by 09:00, before climbing to a peak of 7 at 12:00. This midday intensity signifies a need for sun protection, especially during the height of the day when UV exposure is most potent. The index begins to decline in the afternoon, dropping to 5 at 14:00 and settling back to 1 by 17:00. By 18:00 and into the evening, the UV Index sharply drops to 0, marking a safe time to enjoy outdoor activities without the risk of sunburn. Stay sun-safe!
| 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 | 9 | very high | 15 min |
| 13:00 | 8 | very high | 15 min |
| 14:00 | 6 | high | 25 min |
| 15:00 | 4 | moderate | 30 min |
| 16:00 | 2 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 0 | low | 45 min |
| 19:00 | 0 | low | 45 min |
The UV Index exhibits significant seasonal changes, peaking between January and April with extreme levels ranging from 15 to 16, which translates to a rapid burn time of just 10 minutes. Following this intense period, May marks a decrease to a very high index of 8, with a slightly longer burn time of 15 minutes. From June to July, the UV exposure remains high, with indices of 6 to 7, allowing for up to 25 minutes of safe sun exposure. As summer fades, August sees a rise again to a very high index of 9, followed by a return to extreme levels in September and throughout the fall months into December, where the index consistently hovers around 14 to 15 with a 10-minute burn time. Consequently, the highest risk months for UV exposure are from January to April and September to November. Visitors and residents are strongly advised to take necessary precautions during these periods, such as using sunscreen, wearing protective clothing, and seeking shade to minimize the risk of sunburn and long-term skin damage.
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 |
| Biritiba Mirim | 16 | 15 | 12 | 11 | 8 | 6 | 7 | 9 | 11 | 13 | 14 | 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 |