Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors of Sao Francisco do Sul, Brazil, a picturesque coastal town where sun exposure can vary significantly throughout the day. As the climate falls into the Cfa zone, the warm and humid conditions make it essential to be aware of UV levels to prevent sunburn and protect your skin health. For instance, the UV Index peaks at 6 around midday, indicating a moderate risk, which underscores the importance of taking precautions during those hours. By staying informed about the UV Index, you can better enjoy the sun while safeguarding your well-being in this beautiful sun-soaked destination.
The UV Index today showcased a notable increase from the early morning hours, starting at a gentle 1 at 07:00 and 08:00. As the sun rose higher in the sky, the index climbed steadily, reaching a significant 6 by 12:00, indicating a peak in UV radiation and the need for sun protection. The afternoon saw a slight decline, with values dropping to 4 at 14:00 and falling further to 2 by 15:00. As the day wound down, the UV index returned to a safer range, ending the day at 0 by 19:00. It’s crucial to stay informed and safeguard your skin during those high UV hours!
| 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 | 6 | high | 25 min |
| 13:00 | 5 | moderate | 30 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 |
The UV Index exhibits significant seasonal variations, peaking at extreme levels from January to March and again in October through December, with values soaring to 15. Notably, February and November also maintain an index of 14, indicating extremely high risks for sunburn, with minimal burn times of just 10 minutes. Transitioning into the spring and summer months, the UV Index decreases to a very high level of 10 in April and 8 in August, while the burn time gradually increases to 15 and 25 minutes in May and June, respectively. July and August maintain a high risk, with burn times extending to 25 minutes, before returning to very high in September. Given these data, it's crucial for visitors and residents alike to practice sun safety—especially from January through March and again from October to November—by seeking shade, wearing protective clothing, and applying sunscreen regularly to mitigate the risk of UV exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sao Francisco do Sul | 15 | 14 | 12 | 10 | 7 | 6 | 6 | 8 | 10 | 13 | 14 | 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 |