Last updated: May 3, 2025
Understanding the UV Index is essential for everyone in Porto Alegre, Brazil, where the climate offers warm, humid summers and occasional intense sun exposure. Recognizing the UV levels throughout the day helps you protect your skin from sunburn and long-term health issues. With peak UV readings reaching 6 at noon, the potential for harm increases significantly, making awareness crucial for maintaining skin health. As you navigate the city's sunny days, keep an eye on the UV Index to enjoy the outdoors safely while minimizing your risk of skin damage.
The UV Index over the day shows a dynamic range of exposure, starting off calm in the early hours. At 07:00 and 08:00, it remains at a gentle 1, perfect for a leisurely morning. As the sun climbs higher, the index rises steadily, reaching 2 by 09:00 and peaking at 6 around 12:00, indicating caution is necessary for outdoor activities. The intensity slightly dips from there, down to 5 by 13:00 and then to 4 at 14:00, before gradually decreasing to 1 by 16:00. Finally, the UV exposure diminishes to 0 by 18:00, signaling a safe end to the day. Stay mindful of those peak hours for a fun and safe experience in the sun!
| 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 | 3 | 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 | 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, seasonal UV changes show extreme levels from January to March, with a UV Index peaking at 14 during these months and a rapid burn time of just 10 minutes. As spring progresses, April sees a decrease to a UV Index of 9, indicating a very high exposure category, with burn times extending to 15 minutes. By May, the UV Index drops to 6 (high), where residents can spend up to 25 minutes in the sun without burning. The summer months of June and July bring about a moderate UV Index of 4 and 5 respectively, allowing for 30 minutes of sun exposure before a burn occurs. However, from August to October, a rise to high and extreme levels returns, urging caution with burn times shrinking back down to 15-10 minutes in September and October. November and December again reflect extreme conditions, with Ultraviolet exposure remaining a concern. Visitors and residents are strongly advised to employ sun protection measures—such as wearing sunscreen, hats, and protective clothing—especially during the high-risk winter and early spring months, to minimize the risk of skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Porto Alegre | 14 | 13 | 12 | 9 | 6 | 4 | 5 | 7 | 9 | 12 | 13 | 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 |