Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors in Santiago Atitlán, Mexico, given the area's unique climate and high exposure to sun. As a breathtaking destination in a region with a temperate, yet sunny, climate, knowing the UV levels can help you protect your skin from harmful rays, preventing sunburn and promoting long-term skin health. With peak UV Index values reaching 14 during the afternoon hours, awareness of these levels is essential for enjoying outdoor activities safely. Whether you're hiking along stunning trails or soaking in the beauty of Lake Atitlán, being informed about UV exposure risks can help you make the most of your experience without compromising your well-being.
The UV Index throughout the day paints a vivid picture of sun intensity, peaking dramatically around noon. Starting at a modest 1 at 7:00 AM, the index gently climbs to 3 by 9:00 AM, before hitting a striking 6 at 10:00 AM. As the sun rises higher, the UV Index reaches its zenith at 12:00 PM with a blistering score of 12, and then surges to a peak of 14 by 1:00 PM. The intensity begins to wane in the afternoon, dropping to 11 at 3:00 PM and further declining to 4 by 5:00 PM. As evening approaches, a safe 2 is reached by 6:00 PM, and the day ends with a gentle 1 by 7:00 PM. It’s a clear reminder to stay protected during the peak hours when the sun’s rays are at their strongest!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 9 | very high | 15 min |
| 12:00 | 12 | extreme | 10 min |
| 13:00 | 14 | extreme | 10 min |
| 14:00 | 13 | extreme | 10 min |
| 15:00 | 11 | extreme | 10 min |
| 16:00 | 8 | very high | 15 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, seasonal UV changes reveal significant variation, particularly between January and October, where the UV Index frequently reaches extreme levels. The high-risk months are clearly identified as February to September, with the UV Index peaking at 15 in May and July, which corresponds to a burn time of just 10 minutes. Visitors and residents are strongly advised to take precautionary measures during these months, including wearing protective clothing, applying broad-spectrum sunscreen, and seeking shade when possible. Outside of these high-risk months, the UV Index remains very high in January, November, and December, suggesting that caution should still be exercised year-round to minimize the risk of skin damage from UV exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Guadalajara UVI | 9 | 11 | 14 | 14 | 14 | 13 | 13 | 13 | 13 | 12 | 9 | 8 |
| Iztapalapa UVI | 10 | 12 | 14 | 15 | 14 | 14 | 14 | 14 | 14 | 12 | 10 | 8 |
| Ecatepec de Morelos UVI | 10 | 12 | 14 | 15 | 15 | 14 | 14 | 13 | 14 | 12 | 10 | 8 |
| Mexico City UVI | 10 | 12 | 14 | 15 | 15 | 14 | 14 | 13 | 14 | 12 | 10 | 8 |
| Santiago Altitlan | 10 | 12 | 14 | 14 | 15 | 14 | 15 | 13 | 14 | 12 | 10 | 9 |
| Puebla UVI | 10 | 12 | 14 | 15 | 15 | 15 | 15 | 14 | 14 | 13 | 10 | 9 |