August Weather in Charleston, United States

Last updated: June 24, 2025

In August, the average temperature in Charleston, United States hovers around 23°C (74°F), offering a pleasant climate for outdoor activities. Expect minimum temperatures to dip to 13°C (55°F), while highs can reach up to 34°C (93°F). With 114 mm (4.5 in) of precipitation spread across about 15 days, don’t forget your umbrella! The average humidity is a comfortable 73%, ensuring a refreshing atmosphere throughout the month.

August Temperature in Charleston

In August in Charleston, the average temperature is 23°C (74°F). Maximum temperatures can reach 34°C (93°F), while minimums can drop to as low as 13°C (55°F). This pleasant climate makes Charleston an ideal destination for travelers seeking a comfortable and enjoyable experience during their visit.

August Weather in Charleston: Daily Temperature Highs, Lows, and Averages

The chart illustrates August temperature patterns in Charleston, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Charleston, August typically has an average temperature of 23°C (74°F), with highs reaching up to 34°C (93°F) and lows dropping to around 13°C (55°F).
JanFebMarAprMayJunJulAugSepOctNovDec364247566672767470604641
Data source: Temperature data for Charleston generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

August Precipitation in Charleston

In Charleston in August, the precipitation amount is 114 mm (4.5 in) spread over a duration of 15 days.

August Precipitation Trends in Charleston

The chart displays monthly precipitation patterns in Charleston, with values for each month alongside August’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how August’s conditions compare to those of other months. In Charleston, August typically receives around 114 mm (4.5 inches) of precipitation spread over approximately 15 days.
JanFebMarAprMayJunJulAugSepOctNovDec10115211913415915412411410311778124
Data source: Precipitation data for August generated using information from the Copernicus Climate Change Service.
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August Humidity in Charleston

In Charleston in August, humidity is 73%. With an average temperature of 23°C (74°F), this humidity feels like a warm, enveloping blanket, making traveling a bit sweaty and heavy, but still pleasant if you stay hydrated and take breaks in the shade.

August Average Humidity in Charleston

This chart illustrates the average monthly humidity levels in Charleston, with August’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In August, average humidity in Charleston is approximately 73%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec88%88%88%87%82%84%82%73%74%81%89%86%
Data source: Humidity data for August generated using information from the Copernicus Climate Change Service.

August UV Index in Charleston

In Charleston in August, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in Charleston.

Maximum UV Index Levels in Charleston for August

The chart shows the monthly maximum UV Index (UVI) for Charleston in August, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In August, the maximum UV index in Charleston typically reaches 10, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec3579101010108753
Data source: Charleston August UVI data generated using 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.

How August Weather in Charleston Compares to Other Months

Weather in Charleston varies notably across the year, with each month offering distinct climate conditions. This page compares August’s weather to other months in Charleston, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Charleston, showing how August’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather2°C (37°F)101 mm (4.0 inches)88%moderate
February Weather5°C (42°F)152 mm (6.0 inches)88%moderate
March Weather9°C (48°F)119 mm (4.7 inches)88%high
April Weather13°C (56°F)134 mm (5.3 inches)86%very high
May Weather19°C (66°F)159 mm (6.3 inches)82%very high
June Weather22°C (72°F)154 mm (6.1 inches)84%very high
July Weather25°C (77°F)124 mm (4.9 inches)82%very high
August Weather23°C (74°F)114 mm (4.5 inches)73%very high
September Weather21°C (70°F)103 mm (4.0 inches)73%very high
October Weather16°C (61°F)117 mm (4.6 inches)81%high
November Weather8°C (46°F)78 mm (3.1 inches)89%moderate
December Weather5°C (41°F)124 mm (4.9 inches)86%moderate

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