Last updated: August 1, 2025
Understanding the UV Index in Guarujá, Brazil is crucial for safeguarding your skin and overall health. With its warm, tropical climate, Guarujá experiences significant sun exposure, particularly during peak hours when UV levels can reach as high as 6 around midday. Being aware of these levels can help you take proactive measures against sunburn and long-term skin damage. From leisurely beach days to outdoor activities, staying informed about UV intensity is key to enjoying all that Guarujá has to offer while protecting yourself from harmful rays. Don't let a sunny day turn into a painful experience—knowledge is your best defense!
The UV Index throughout the day tells a compelling story of sun exposure. Starting at 07:00, the index is a low 1, gradually rising to a moderate 3 by 09:00. As the clock strikes 10:00, it hits 4, indicating increasing intensity. The peak occurs between 11:00 and 13:00, where the index reaches its maximum of 6, suggesting a need for sun protection. From this high point, the index begins to descend, dropping to 5 at 14:00, before tapering off to 3 by 15:00. As daylight wanes, the UV Index falls sharply to 1 by 16:00, ultimately dropping to 0 by 18:00 and staying there through 19:00. This highlights the importance of vigilance during midday hours when UV radiation is at its strongest.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 8 | very high | 15 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 | 0 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, UV Index levels fluctuate significantly, with the months of January through April and September through November marked by extreme exposure (UV Index 11 and above) and a very short burn time of just 10 minutes. Notably, February and November see a peak UV Index of 14, indicating heightened risk. The high-risk months for UV exposure, therefore, are January, February, September, October, and November. Conversely, during the warmer months of May to August, the UV Index decreases to very high and high categories, with longer burn times of 15 to 25 minutes. Visitors and residents are advised to take precautions during these high-risk periods, such as wearing protective clothing, using high-SPF sunscreen, and seeking shade when UV levels are at their peak.
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 |
| Guaruja | 15 | 14 | 12 | 11 | 8 | 6 | 6 | 9 | 11 | 13 | 14 | 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 |