Last updated: July 2, 2025
Understanding the UV Index is crucial for residents and visitors of San Juan Bautista, Peru, where the climate is characterized as BWk, resulting in notable UV exposure throughout the year. Awareness of UV levels can significantly aid in sunburn prevention and promoting skin health, especially during peak hours when the index reaches dangerous levels of 10 to 11 between 11:00 AM and 1:00 PM. With these high readings typical for this region, it’s vital to take proactive measures to protect your skin from potential harm, ensuring you enjoy the sunny Peruvian days safely.
As the day unfolds, the UV Index reaches its peak between 11:00 AM and 12:00 PM, soaring to a striking 11. The morning starts gently, with the index at a modest 1 by 7:00 AM, slowly climbing to 4 by 9:00 AM. The sun then intensifies, pushing the index to a strong 10 at 11:00 AM, signaling it's time to seek shade and protect your skin. By 2:00 PM, it begins to wane, dropping to 8, and further decreases to 5 by 3:00 PM. As the afternoon progresses, the index continues to fall, reaching 2 at 4:00 PM, and finally settling at 1 by 5:00 PM and 0 as the sun sets at 6:00 PM. Stay aware and shield yourself during those crucial midday hours!
| 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 | 7 | high | 25 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 5 | 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 exhibits significant seasonal variation, with extremely high levels persisting throughout the year. From January to March, the UV Index remains at 16, indicating an extreme risk of harm from unprotected sun exposure, with a burn time of just 10 minutes. In April and May, while the Index decreases slightly to 14 and 12, respectively, the risk remains within the extreme category, still demanding vigilance. The summer months see a marginal drop in June to 10 (very high) before rising back to high levels in July and August. September returns to an Index of 14, and the levels peak again in November at 17. Given this data, it is crucial for visitors and residents to take appropriate sun safety measures, especially during these high-risk months. Always wear sunscreen, protective clothing, and seek shade whenever possible, particularly during midday hours, to minimize risk of harmful UV exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Callao UVI | 14 | 14 | 14 | 12 | 10 | 9 | 10 | 11 | 12 | 13 | 14 | 13 |
| Lima UVI | 14 | 14 | 14 | 12 | 10 | 9 | 10 | 11 | 12 | 13 | 14 | 13 |
| Trujillo UVI | 15 | 15 | 15 | 14 | 12 | 11 | 11 | 11 | 13 | 14 | 14 | 14 |
| Chiclayo UVI | 14 | 15 | 15 | 14 | 13 | 11 | 11 | 12 | 15 | 14 | 14 | 13 |
| San Juan Bautista | 16 | 16 | 16 | 14 | 12 | 10 | 11 | 12 | 14 | 16 | 17 | 16 |
| Arequipa UVI | 18 | 17 | 17 | 15 | 12 | 10 | 11 | 13 | 15 | 17 | 18 | 17 |