Last updated: September 1, 2025
Understanding the UV Index is crucial for the residents and visitors of Zacatecas, Mexico, where the combination of high altitude and a dry, arid climate often results in intense sun exposure. Being aware of UV levels not only helps prevent painful sunburns but also plays a significant role in maintaining long-term skin health. With peak UV Index values reaching as high as 12 during midday, it's essential to take proactive measures against the harmful effects of ultraviolet radiation. Whether you're exploring the historic streets or enjoying outdoor activities, staying informed about the UV Index can make all the difference in protecting your skin while embracing the beautiful sun-soaked days of Zacatecas.
At dawn, the UV Index starts low, peaking at 1 around 7:00 AM and remaining steady until 9:00 AM. As the sun climbs higher in the sky, exposure increases, hitting 4 by 10:00 AM. The intensity escalates sharply, reaching a striking 10 at 12:00 PM and peaking at 12 between 1:00 PM and 2:00 PM—the hottest moment of the day. Following this peak, the UV Index gracefully declines, dropping to 5 by 5:00 PM and further to 3 by 6:00 PM. As evening approaches, it wraps up with a return to 1 by 7:00 PM. It's a clear reminder to seek shade during peak hours and protect your skin!
| 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 | 4 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 min |
| 15:00 | 9 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV Index values display significant seasonal variation, with higher risks typically occurring from February to September. The months of April through September highlight an extreme exposure category with a peak UV Index of 12, resulting in a very short burn time of just 10 minutes. Notably, February and March also present high to very high risks, contributing to the overall increase in UV exposure during spring. As we move into the colder months, October to December, UV levels decrease, though November and December still pose moderate risks with burn times of 25 minutes. To ensure safety, visitors and residents are advised to take precautions—wearing sunscreen, protective clothing, and seeking shade during peak hours, especially during the high-risk months of April to September.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Zacatecas | 7 | 9 | 10 | 12 | 12 | 12 | 12 | 12 | 11 | 10 | 7 | 6 |
| 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 |
| Puebla UVI | 10 | 12 | 14 | 15 | 15 | 15 | 15 | 14 | 14 | 13 | 10 | 9 |