Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors of Si'en, China, as it plays a significant role in protecting skin health and preventing sunburn. With the region's humid subtropical climate (Cfa), Si'en experiences heightened UV exposure, especially during midday when the index peaks at a striking 12—indicating a high risk of harm from unprotected sun exposure. Being aware of UV levels can help you take essential precautions, ensuring a safe and enjoyable experience while soaking up the sun. Stay informed, stay protected, and embrace the beauty of Si'en while keeping your skin health in check!
At dawn, the UV Index starts off gently, peaking at just 1 by 7:00 AM. As the sun climbs higher, its intensity increases rapidly, reaching 4 by 9:00 AM and striking 10 by 11:00 AM—a clear warning to seek shade or slather on sunscreen. The highest reading of 12 occurs at both noon and 1:00 PM, indicating peak solar intensity. Fortunately, as afternoon approaches, the index begins to wane, dropping to 8 by 3:00 PM and further declining to below 5 by 4:00 PM. By the time 7:00 PM rolls around, the UV danger has diminished significantly, settling back to a safe 1. Stay protected during those intense midday hours!
Time | UVI | Category | Time to Burn |
---|---|---|---|
07:00 | 1 | low | 45 min |
08:00 | 2 | low | 45 min |
09:00 | 4 | moderate | 30 min |
10:00 | 7 | high | 25 min |
11:00 | 10 | very high | 15 min |
12:00 | 12 | extreme | 10 min |
13:00 | 12 | extreme | 10 min |
14:00 | 11 | extreme | 10 min |
15:00 | 8 | very high | 15 min |
16:00 | 5 | moderate | 30 min |
17:00 | 3 | moderate | 30 min |
18:00 | 1 | low | 45 min |
19:00 | 1 | low | 45 min |
Throughout the year, UV exposure levels fluctuate significantly, with high-risk months generally spanning from February through September, where the UV Index reaches extreme levels of 11 and higher. Notably, May, July, and August peak at a UV Index of 13, demanding particularly cautious behavior as the burn time drops to just 10 minutes. As we transition to fall and winter, UV levels gradually decrease, with October and November still presenting a very high concern, while January and December return to a high category with more extended burn times of 25 minutes. To protect against the harmful effects of UV radiation, visitors and residents should prioritize sun safety practices—such as wearing protective clothing, applying broad-spectrum sunscreen, and seeking shade—particularly during the high-risk months when UV exposure is at its peak.
UV Risk Categories
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Beijing UVI | 2 | 3 | 5 | 8 | 9 | 9 | 10 | 9 | 7 | 6 | 4 | 2 |
Chengdu UVI | 5 | 6 | 8 | 10 | 12 | 11 | 11 | 10 | 11 | 8 | 6 | 4 |
Shanghai UVI | 5 | 6 | 8 | 10 | 10 | 11 | 12 | 11 | 11 | 8 | 6 | 4 |
Si'en | 7 | 9 | 11 | 11 | 13 | 12 | 13 | 13 | 11 | 10 | 8 | 6 |
Guangzhou UVI | 7 | 9 | 11 | 12 | 13 | 13 | 13 | 12 | 11 | 10 | 9 | 7 |
Shenzhen UVI | 7 | 10 | 12 | 12 | 14 | 13 | 13 | 13 | 12 | 11 | 9 | 7 |