UV Index in Charleston, United States

Last updated: June 2, 2025

Awareness of the UV Index is crucial for residents and visitors in Charleston, United States. Understanding UV levels not only helps in preventing sunburn but also plays a significant role in maintaining overall skin health. With Charleston's warm Cfa climate, the sun's rays can be intense, especially around midday when the UV Index peaks at 11—a level deemed very high. Being informed about these fluctuations allows you to take necessary precautions and enjoy the beauty of this vibrant city safely while minimizing the risks associated with UV exposure.

Hourly UV Index in Charleston

The UV Index for the day showcases a striking pattern, starting moderate at 7:00 AM with a value of 1. As the sun climbs higher, the index steadily rises, hitting 3 by 9:00 AM, and then surging to a peak of 11 between 1:00 PM and 2:00 PM. This indicates a high risk of harm from unprotected sun exposure during midday. Following the peak, the UV Index gradually declines to 4 by 5:00 PM and further decreases to 1 by 7:00 PM, emphasizing the critical importance of sun protection during the intense midday hours. It’s advisable to seek shade and wear sunscreen if you're outside during the peak period!

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.
TimeUVICategoryTime to Burn
07:001low45 min
08:001low45 min
09:003moderate30 min
10:005moderate30 min
11:008very high15 min
12:0010very high15 min
13:0011extreme10 min
14:0011extreme10 min
15:009very high15 min
16:007high25 min
17:004moderate30 min
18:002low45 min
19:001low45 min

Monthly UV Index Trends in Charleston

Throughout the year, UV Index levels exhibit noteworthy seasonal changes, with high-risk months identified from March to August, when exposure reaches very high or extreme levels. In March and April, the UV Index peaks at 9 and 10, respectively, indicating a transition into the more hazardous summer months. May through August experience the highest UV Index of 11, categorized as extreme, which necessitates diligent sun protection within a burn time of just 10 minutes. As September and October arrive, UV levels remain considerable, with a very high index of 9 and 8, and slowly tapering off towards the end of the year. It is crucial for both visitors and residents to take appropriate precautions during these months, such as wearing sunscreen, protective clothing, and seeking shade during peak hours to minimize the risk of UV-related skin damage.

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.
JanFebMarAprMayJunJulAugSepOctNovDec47910111111119864
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.
 JanFebMarAprMayJunJulAugSepOctNovDec
Chicago UVI34689101098642
Brooklyn UVI35681010998642
New York City UVI35681010998642
Los Angeles UVI46891011111010754
Charleston47910111111119864
Houston UVI589111112121110975