UV Index in Charleston, United States

Last updated: May 3, 2025

Awareness of the UV Index in Charleston, South Carolina, is crucial for residents and visitors alike, as it plays a significant role in sunburn prevention and overall skin health. Understanding the daily levels of UV exposure can help you take necessary precautions against harmful rays that can lead to skin damage and increase your risk of skin cancer. Charleston’s Cfa climate brings warm and sunny days, resulting in elevated UV levels, especially during midday when the index peaks at a remarkable 11. With such risks, staying informed about the UV Index is essential for enjoying the region's beautiful outdoors while protecting your skin.

Hourly UV Index in Charleston

As the sun rises, the UV Index remains low, peaking at 1 by 08:00. However, by 10:00, the intensity ramps up to 5, signaling the start of stronger rays. The real surge occurs between 12:00 and 14:00, where the UV Index hits a maximum of 11, indicating a very high risk of harm from unprotected sun exposure. As the afternoon unfolds, from 15:00 onward, the index gradually declines, reaching 4 by 17:00 and dropping further to 1 by 19:00. It's essential to take precautions during peak hours, especially from 11:00 to 14:00, to stay safe under the blazing sun!

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	2	low	45 min
10:00	5	moderate	30 min
11:00	7	high	25 min
12:00	10	very high	15 min
13:00	11	extreme	10 min
14:00	11	extreme	10 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, the UV Index experiences notable fluctuations, with the highest values occurring from March to August. Specifically, May through July are characterized by an extreme UV Index of 11, necessitating caution as the burn time is reduced to just 10 minutes. These peak months represent a high-risk period for sunburn and potential skin damage. In contrast, January and December see the lowest UV exposure, categorized as moderate with burn times of up to 30 minutes. Visitors and residents are strongly advised to take protective measures, such as wearing sunscreen and protective clothing, particularly during the high-risk months of March to August. Staying informed about the UV Index can help ensure a safer experience outdoors.

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
Los Angeles UVI	4	6	8	9	10	11	11	10	10	7	5	4
Charleston	4	6	8	10	11	11	11	10	9	7	6	3
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5