Last updated: May 3, 2025
Understanding the UV Index is essential for residents and visitors in Shiwan, China, where sun exposure can lead to serious skin health issues if precautions aren't taken. The UV Index measures the strength of ultraviolet radiation from the sun, making it a critical tool for sunburn prevention and overall skin health. With Shiwan's Cwa climate, characterized by hot summers and moderate UV levels, it's especially vital to be aware of the peak index times—reaching as high as 13 from noon to early afternoon. Protecting your skin from potential damage during these hours can safeguard your health and enhance your outdoor experiences in this vibrant city.
As the sun rises, the UV Index starts its slow climb, peaking at 13 between noon and 1 PM, signaling extreme UV exposure. The day begins gently at 7 AM with a minimal index of 1, but by 10 AM, it reaches 9, urging sun-sensitive individuals to seek protection. The highest reading of 13 persists for two hours, making midday the most critical time for sun safety. As the afternoon rolls in, the index gradually decreases, dipping to 7 by 3 PM, and further waning into the evening with values of 4 at 4 PM, 2 at 5 PM, and falling to a comfortable 1 by 6 PM. Finally, the UV Index settles at 0 after sunset, marking the end of a sun-drenched day.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 5 | moderate | 30 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 12 | extreme | 10 min |
| 12:00 | 13 | extreme | 10 min |
| 13:00 | 13 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, UV index levels fluctuate significantly, indicating varying risks for sun exposure. January and December experience lower UV indices of 7, categorized as high, with a burn time of 25 minutes. February marks the beginning of higher risks, peaking at 9, considered very high, and leading into March, where the UV index reaches an extreme 12, necessitating a burn time of only 10 minutes. This extreme exposure continues through May and June, maintaining a maximum index of 13. The summer months, particularly July, also reflect this intensity, with similar ratings sustained until August and September, where it drops slightly to 12 and 11, respectively. As the year winds down, October and November revert back to a very high index of 9-10, culminating the season's risks. Visitors and residents are strongly advised to take protective measures during the high-risk months of February through September, ensuring they limit their sun exposure, wear protective clothing, and apply sunscreen regularly to prevent skin damage.
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 |
| Shiwan | 7 | 9 | 12 | 11 | 13 | 13 | 13 | 12 | 11 | 10 | 9 | 7 |
| 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 |