Last updated: July 2, 2025
Understanding the UV Index is essential for residents and visitors of Ciudad Vieja, Guatemala, especially given its unique Cwb climate, characterized by a mix of tropical and temperate conditions. As UV levels can soar as high as 14, especially between noon and early afternoon, awareness of these values is crucial for preventing sunburn and maintaining skin health. With a typical climate that can expose individuals to high UV radiation throughout the day, taking proactive measures can protect against the harmful effects of the sun and enhance your overall well-being. Stay informed and enjoy the beautiful vistas of Ciudad Vieja safely!
The UV Index rises steadily through the morning, starting at a gentle 1 at 07:00 and escalating to a peak of 14 by 12:00. As the sun reaches its zenith, the index hits a blistering 12 at 11:00 and maintains an impressive 13 at 13:00, signaling ideal conditions for sunbathers and outdoor enthusiasts. However, the intensity of UV rays begins to wane after 14:00, dipping to 10 and further declining to 3 by mid-afternoon. As evening approaches, the index falls sharply to 1 by 17:00 and settles at 0 by 19:00, marking a gradual retreat from peak sun exposure. For safety, sunscreen and protective clothing are essential during the midday hours, especially from 10:00 to 14:00 when UV radiation is at its strongest.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 7 | high | 25 min |
| 10:00 | 10 | very high | 15 min |
| 11:00 | 12 | extreme | 10 min |
| 12:00 | 14 | extreme | 10 min |
| 13:00 | 13 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
The UV Index experiences significant variability throughout the year, peaking from February to July, where it reaches extreme levels of 12 to 14 with a consistent burn time of just 10 minutes. March sees the highest index at 14, closely followed by April, May, and June. As summer fades into autumn, slight decreases are noted, with August and September at 13, followed by October at 12. The risk remains high through November and December, although the indices drop to 10 and 9 respectively, resulting in slightly longer burn times of 15 minutes. Visitors and residents are strongly advised to take precautions, especially during peak months by utilizing broad-spectrum sunscreen, wearing protective clothing, and seeking shade during peak sunlight hours to minimize the risk of harmful UV exposure. Always remain vigilant, even in winter months, as UV radiation can still pose a significant threat.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ciudad Vieja | 11 | 12 | 14 | 14 | 14 | 14 | 14 | 13 | 13 | 12 | 10 | 9 |
| Petapa UVI | 11 | 13 | 14 | 15 | 14 | 14 | 14 | 14 | 14 | 13 | 10 | 10 |
| Villa Nueva UVI | 11 | 13 | 14 | 15 | 14 | 14 | 14 | 14 | 14 | 13 | 10 | 10 |
| Mixco UVI | 11 | 13 | 15 | 15 | 14 | 14 | 14 | 14 | 14 | 13 | 11 | 10 |
| Guatemala City UVI | 11 | 13 | 15 | 15 | 14 | 14 | 14 | 14 | 14 | 13 | 11 | 10 |
| San Juan Sacatepequez UVI | 11 | 13 | 15 | 15 | 14 | 14 | 15 | 14 | 14 | 13 | 11 | 10 |