Last updated: July 2, 2025
Understanding the UV Index is essential for residents and visitors in Sao Joao do Piaui, Brazil, where the sun shines brightly throughout the year. As this vibrant city experiences a BSh climate, outdoor activities are abundant, but so are the risks associated with high UV levels, particularly in the midday hours. With peak UV Index values reaching 11 between noon and 1 PM, awareness is crucial to prevent sunburn and protect skin health. By staying informed about the daily UV forecast, you can enjoy all that Sao Joao do Piaui has to offer while safeguarding your well-being under the sun.
The UV Index today peaked dramatically in the late morning, starting from a low of 1 at 07:00 and climbing to an impressive 11 by 12:00. This intense exposure reached its zenith at 11:00, where precautions were essential as the Index hit 10. As the afternoon progressed, the UV levels began to gradually decline, dropping to 4 by 15:00 and further down to a modest 2 by 16:00. By the evening, the sun had softened, bringing the UV Index back to 1 at 17:00, and ultimately fading to 0 by 18:00, when the day's light had nearly vanished. Make sure to stay protected during peak hours to enjoy the sunshine safely!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 5 | moderate | 30 min |
| 10:00 | 8 | very high | 15 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 7 | 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 remains consistently high throughout the year, with extreme exposure categories dominating every month. Notably, January to March see a peak UV Index of 15, marking these months as high-risk for skin damage, where a mere 10 minutes of unprotected sun exposure can lead to burns. The UV levels gradually decrease from April to June, dropping to 11, but still maintaining an extreme level of risk. Even later months into August and September, the UV Index remains significant, reaching 12 and 13, respectively. With high UV levels persisting into October and November (both at 14), it’s crucial for visitors and residents to take proactive measures, including wearing sunscreen, hats, and UV-protective clothing, especially during the midday hours, to mitigate the risks associated with prolonged sun exposure.
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 |
| 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 |
| Sao Joao do Piaui | 15 | 15 | 15 | 14 | 12 | 11 | 11 | 12 | 13 | 14 | 14 | 14 |