UV Index in Si'an, China

Last updated: May 3, 2025

Understanding the UV Index is essential for residents and visitors in Si'an, China, as it plays a crucial role in protecting skin health and preventing painful sunburns. With the region's Cfa climate, characterized by hot summers and mild winters, Si'an experiences varying UV exposure throughout the year—reaching a peak index of 11 during midday. This highlights the need to be vigilant about UV levels, particularly between 10 AM and 3 PM, when the sun's rays are most intense. By staying informed and taking protective measures, you can enjoy the sun safely while preventing long-term skin damage.

Hourly UV Index in Si'an

The UV Index for the day follows a dynamic trend, peaking during the midday hours. Starting at a modest 2 at 7:00 AM, the intensity gradually intensifies, reaching 4 by 8:00 AM. As the sun climbs higher, the index escalates significantly, hitting a striking 9 at 10:00 AM and reaching its zenith of 11 at 12:00 PM. After this peak, a gradual decline sets in, with the index dropping to 5 by 3:00 PM before tapering off to 1 by 5:00 PM. The day concludes with a UV Index of 0 by 7:00 PM, signaling a clear drop in potential UV exposure. It's a reminder to stay sun-smart, especially during the midday hours when the UV rays are at their strongest!

Average solar exposure data for the current time of the year. Actual values may vary and depend on many factors, such as cloud cover, vegetation cover, surface type, etc.
Time	UVI	Category	Time to Burn
07:00	2	low	45 min
08:00	4	moderate	30 min
09:00	6	high	25 min
10:00	9	very high	15 min
11:00	10	very high	15 min
12:00	11	extreme	10 min
13:00	10	very high	15 min
14:00	8	very high	15 min
15:00	5	moderate	30 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

Monthly UV Index Trends in Si'an

The seasonal UV changes indicate a significant increase in UV exposure as the year progresses, with high-risk months being from March to October, where the UV Index reaches as high as 11 (extreme). Specifically, May to August poses the greatest risk, with a burn time of just 10 minutes in direct sunlight. Residents and visitors are advised to take precautionary measures during these months, including wearing protective clothing, sunglasses, and sunscreen to mitigate harmful effects. As the UV Index begins to decline in September, it remains important to stay vigilant until it drops to more moderate levels by December, when the burn time increases to 30 minutes again.

Monthly Maximum UV Index for Si'an, China

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Si'an. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.

Data source: Statistical UV Index data for Si'an, based on information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

Compare Si'an UV Index with Other China Cities

The table above highlights how UV exposure in Si'an compares to other major locations across China. This comparison helps travelers and residents better understand regional sun intensity and plan outdoor activities with sun safety in mind.

Si'an's solar exposure compared to other cities in China. Generated using Copernicus Atmosphere Monitoring Service information.
	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
Si'an	5	6	9	10	11	11	11	11	10	8	6	4
Shanghai UVI	5	6	8	10	10	11	12	11	11	8	6	4
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