Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors in São José, Brazil, where the climate is characterized by warm temperatures and abundant sunshine. Awareness of UV levels is essential for preventing sunburn and protecting skin health, especially during the peak hours when the index reaches levels 4 and 5. With typical UV exposure risks heightened between 10 AM and 2 PM, being informed can help you enjoy the vibrant outdoor lifestyle in São José while minimizing your risk of skin damage. Stay savvy about the UV Index, and safeguard your skin under the Brazilian sun!
As the sun rises, the UV Index begins at a low 1 at 7:00 AM, indicating minimal sun exposure risk. By 9:00 AM, it climbs to 2, suggesting it's time to start thinking about sun protection. The intensity peaks at 12:00 PM and 1:00 PM, reaching a high of 5, at which point it's crucial to apply sunscreen and seek shade. As the afternoon progresses, the index gently declines to 4 by 2:00 PM and further down to 2 by 3:00 PM. By 5:00 PM, the risk decreases significantly to 1, before tapering off to 0 after 6:00 PM, signaling a safe window for evening activities. Be mindful of the sun’s strength during the midday 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 | 3 | moderate | 30 min |
| 11:00 | 4 | moderate | 30 min |
| 12:00 | 5 | moderate | 30 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 |
Throughout the year, UV exposure tends to peak in the winter months of January, February, and March, with an extreme UV Index reaching as high as 15 and a quick burn time of just 10 minutes. As we transition into April, the index drops slightly to 10 but remains in the very high category, demanding care in sun exposure—burn time increases to 15 minutes. The intensity continues to decrease through May and June, where the UV Index falls to 7 and 5, respectively, making these months high to moderate risk for sunburns, with times to burn of 25 to 30 minutes. August shifts back to a high category, while September sees a resurgence of very high UV levels. Late fall and winter months, particularly October through December, re-enter the extreme exposure zone with UV Index values of 12 and 14, emphasizing the need for protective measures. Visitors and residents are strongly advised to stay vigilant during the high-risk months of January, February, March, October, November, and December, ensuring proper sunscreen application and limiting sun exposure during peak hours.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sao Jose | 15 | 14 | 12 | 10 | 7 | 5 | 5 | 7 | 10 | 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 |