Last updated: August 1, 2025
In Tentziantla, part of the beautiful San Marcos region of Mexico, awareness of the UV Index is crucial for everyone enjoying the sunny climate. Understanding UV levels not only aids in sunburn prevention but also plays a significant role in maintaining long-term skin health. With a humid subtropical climate (Cfa) and peak UV Index readings reaching a staggering 14 during midday hours, it’s essential to be informed and take precautions to protect yourself from harmful UV rays. Whether you're hiking, relaxing outdoors, or just soaking in the vibrant culture, knowledge of UV exposure risks can help you enjoy the sun safely.
The UV Index today follows a striking pattern, peaking dramatically through the midday sun. Starting off gently at 1 during the early hours of 07:00 and 08:00, the index climbs steadily, reaching a moderate 3 by 09:00. As the day progresses, anticipation builds, leading to a notable surge at 10:00 with a peak of 5. However, it's 11:00 to 14:00 where the sun truly asserts itself, with the UV Index soaring to 9 at 11:00, hitting an impressive 12 at 12:00, and reaching its apex at 14:00 with 14. The intensity begins to decline post-noon, slipping to 12 at 15:00, 9 at 16:00, and tapering off to 2 by 18:00, before returning to a safe 1 by 19:00. Stay protected during those peak hours when the sun's rays can be particularly harsh!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 0 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 13 | extreme | 10 min |
| 14:00 | 13 | extreme | 10 min |
| 15:00 | 11 | extreme | 10 min |
| 16:00 | 8 | very high | 15 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
The UV Index experiences significant seasonal variations, peaking during the summer months. From January to March, the index is relatively high, with values reaching up to 9 in January but climbing to an extreme 14 by April through July. February and March pose particular risks, with extreme levels and burn times as short as 10 minutes. The summer months of June and July maintain this extreme index, while August and September see a slight decrease but remain at 13. As October approaches, the UV Index remains critical at 12, transitioning to safer levels in November and December with values of 10 and 8, respectively. Visitors and residents are strongly advised to take precautions during high-risk months, particularly from February to October, by wearing appropriate sun protection, seeking shade, and limiting sun exposure to avoid skin damage.
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 |
| Tentziantla (San Marcos) | 9 | 11 | 13 | 14 | 14 | 14 | 14 | 13 | 13 | 12 | 10 | 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 |
| Puebla UVI | 10 | 12 | 14 | 15 | 15 | 15 | 15 | 14 | 14 | 13 | 10 | 9 |