Last updated: July 2, 2025
Awareness of the UV Index is crucial for residents and visitors in Bayan, Mongolia, as it provides key insights into the sun's intensity throughout the day. Understanding these UV levels is essential not only for preventing sunburn but also for maintaining overall skin health. With Bayan's semi-arid climate (BSk), exposure to harmful UV rays can significantly increase during the day, peaking around noon with an index hitting 9. Knowing when to seek shade or apply sunscreen can help protect your skin while you enjoy the great outdoors in this beautiful region.
As the sun rises, the UV Index begins its ascent, starting at a modest 2 at 07:00. By 08:00, it climbs to 3, and then ramps up to 4 by 09:00. As the day progresses, the UV levels peak at 9 from 12:00 to 13:00, indicating a high risk of harm from unprotected sun exposure. The intensity starts to decline after 14:00, dropping to 8 at 14:00 and then decreasing steadily to 6 by 15:00. As the afternoon fades into evening, the index falls further to 4 at 16:00, and then diminishes to a safe 1 by 18:00 and 19:00. It’s crucial to protect your skin during those peak hours to avoid any adverse effects from the sun!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 4 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Seasonal UV changes highlight a significant increase in UV exposure from winter to summer. January and February present low to moderate UV levels, with burn times ranging from 30 to 45 minutes. However, by March and April, the UV Index escalates to moderate and high levels, respectively, with increased caution advised. The months of May through August are particularly high-risk, marked by very high UV levels (Indices 8-9) and a dangerously short burn time of just 15 minutes. As we transition into September, the UV Index drops to high but still poses a risk, while October through December return to low UV levels. Visitors and residents should prioritize sun safety measures during the high-risk months of May to August, including wearing sunscreen, protective clothing, and seeking shade, to minimize the risk of sunburn and long-term skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Darhan UVI | 1 | 3 | 5 | 6 | 8 | 9 | 9 | 8 | 6 | 4 | 2 | 1 |
| Erdenet UVI | 2 | 3 | 5 | 7 | 8 | 9 | 9 | 8 | 6 | 4 | 2 | 1 |
| Bayan | 2 | 3 | 5 | 6 | 8 | 9 | 9 | 9 | 6 | 4 | 2 | 2 |
| Ulan Bator UVI | 2 | 3 | 5 | 7 | 9 | 9 | 9 | 9 | 6 | 4 | 3 | 1 |
| OElgii UVI | 2 | 3 | 5 | 7 | 10 | 9 | 9 | 9 | 7 | 5 | 2 | 1 |
| Khovd UVI | 2 | 3 | 6 | 7 | 10 | 10 | 9 | 9 | 7 | 5 | 2 | 1 |