Last updated: August 1, 2025
In Sao Francisco de Assis, Brazil, staying aware of the UV Index is crucial for safeguarding your skin's health. Understanding UV levels helps in preventing sunburn and reducing the risk of long-term skin damage. With its Cfa climate, the region experiences a unique pattern of UV exposure risks, peaking around midday when UV Index readings reach up to 5. By being informed about these daily fluctuations, residents and visitors can take proactive steps to enjoy the sun safely while protecting their skin from harmful effects.
At dawn, the UV Index starts at 0 at 07:00, offering a safe environment for morning activities. By 08:00 and 09:00, it creeps up to 1, indicating that while the sun is rising, precautions are still minimal. As the day progresses, the sun intensifies—hitting 2 by 10:00 and surging to 5 at both 12:00 and 13:00, the peak hours for UV exposure. It’s the perfect time to apply sunscreen and seek shade if needed. The intensity begins to wane in the afternoon, dropping to 4 at 14:00 and gradually descending to 3 by 15:00. As the sun sets, the UV Index falls back to 1 at 17:00, and finally returns to 0 by 18:00 and 19:00, signaling the end of a day marked by fluctuating UV levels that necessitate careful planning for sun exposure.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 5 | moderate | 30 min |
| 12:00 | 7 | high | 25 min |
| 13:00 | 7 | high | 25 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 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
The UV Index in this region displays significant seasonal variations, peaking in the winter months with extreme exposure levels. From January to March, the UV Index remains alarmingly high (ranging from 14 to 15), indicating high-risk months for sunburn with a burn time of just 10 minutes. As spring arrives in April, the index drops slightly to 9 (very high), allowing for a longer burn time of 15 minutes. During the summer months of June and July, the UV Index stabilizes around 5 (moderate), providing somewhat safer conditions with 30 minutes of burn time. However, it rises again in August at 7 (high) and returns to 9 in September (very high). As autumn transitions to winter, October, November, and December re-enter extreme levels with UV indices between 12 and 14 (10-minute burn times). Visitors and residents are advised to take precautions, using sunscreen, wearing protective clothing, and seeking shade, particularly during the high-risk months from January to March and again in October to December.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sao Francisco de Assis | 15 | 14 | 12 | 9 | 6 | 5 | 5 | 7 | 9 | 12 | 14 | 14 |
| 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 |