UV Index in Charleston, United States

Last updated: July 2, 2025

In Charleston, South Carolina, understanding the UV Index is crucial for protecting your skin and overall health. Excessive sun exposure can lead to painful sunburns and increase the risk of skin cancer, making it essential to stay informed about UV levels throughout the day. With a Cfa climate characterized by hot summers and moderate humidity, Charleston residents and visitors face unique challenges related to UV exposure. During peak hours, especially around noon, the UV Index can soar to severe levels (as high as 10), highlighting the importance of taking proactive measures to safeguard your skin while enjoying the region's beautiful sunshine.

Hourly UV Index in Charleston

The UV Index chart reveals a dynamic daily pattern of solar intensity. Starting early in the day, the UV Index remains low, peaking at 1 by 08:00. However, as the sun reaches its zenith, the index surges dramatically—hitting 7 by 11:00 and soaring to a maximum of 10 between 13:00 and 14:00. This signals a critical window for sun exposure, where protection is essential. As the afternoon progresses, the UV levels begin to decline, dropping to 4 by 17:00, before tapering off to 1 again by evening. To stay safe, it's vital to be cautious during those peak hours!

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	1	low	45 min
08:00	1	low	45 min
09:00	3	moderate	30 min
10:00	5	moderate	30 min
11:00	7	high	25 min
12:00	9	very high	15 min
13:00	10	very high	15 min
14:00	10	very high	15 min
15:00	9	very high	15 min
16:00	7	high	25 min
17:00	4	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Charleston

Throughout the year, UV exposure varies significantly, with the high-risk months spanning from April to September. During this period, the UV Index reaches very high levels, peaking at 10 in May, June, July, and August, where the burn time is as short as 15 minutes. In contrast, January, February, November, and December present moderate risk with an Index of 3 to 5, allowing up to 30 minutes of safe sun exposure. Residents and visitors should take precautions during the spring and summer months, including wearing protective clothing, using sunscreen with high SPF, and seeking shade during peak hours to minimize the risk of sunburn and long-term skin damage. Remember, even on cloudy days, UV rays can still penetrate, so remain vigilant year-round.

Monthly Maximum UV Index for Charleston, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Charleston. 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 Charleston, 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 Charleston UV Index with Other United States Cities

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

Charleston's solar exposure compared to other cities in United States. Generated using Copernicus Atmosphere Monitoring Service information.
	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Chicago UVI	3	4	6	8	9	10	10	9	8	6	4	2
Brooklyn UVI	3	5	6	8	10	10	9	9	8	6	4	2
New York City UVI	3	5	6	8	10	10	9	9	8	6	4	2
Charleston	3	5	7	9	10	10	10	10	8	7	5	3
Los Angeles UVI	4	6	8	9	10	11	11	10	10	7	5	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5