August Weather in Charleston, United States

Last updated: February 24, 2025

In August, Charleston experiences warm and humid weather, with average temperatures around 27°C (81°F). The month sees peaks of up to 35°C (95°F), creating a sultry atmosphere ideal for enjoying coastal breezes. However, be prepared for frequent rain, as 183 mm (7.2 in) of precipitation falls over 21 days, contributing to the city's lush landscape. The humidity levels hover around 81%, making it essential to stay hydrated while exploring the charming streets and vibrant culture of Charleston during this lively summer month.

August Temperature in Charleston

In Charleston, the month of August brings a warm embrace, with temperatures frequently reaching a maximum of 35°C (95°F). The nights offer a mild retreat, settling at a minimum of 21°C (70°F) and providing a comfortable backdrop for evening strolls. With an average temperature of 27°C (81°F), August embodies the peak warmth of the summer season, following the steady climb from the cooler months of January through July. This month is characterized by high humidity, making the heat feel more intense and encouraging locals and visitors alike to seek out the shade or the cooling waters of nearby beaches. As summer gradually transitions into fall, August stands as a vibrant reminder of Charleston’s sultry allure.

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.
JanFebMarAprMayJunJulAugSepOctNovDec525760667479828178725954
Data source: Temperature data for Charleston generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

August Precipitation in Charleston

In August, Charleston experiences a notable high in precipitation, with 183 mm (7.2 in) of rain falling over 21 days, making it one of the wettest months of the year. This deluge follows the trend set by July, which recorded the most rain at 187 mm (7.4 in), and reflects a peak in the summer months when humidity levels soar. As temperatures rise, the city typically sees increased rainfall, creating a humid yet lush environment. Despite a slight decrease from July's totals, August still maintains substantial moisture levels, with rain showers frequently gracing the city’s vibrant landscape. Looking forward, the precipitation pattern begins to ease as September approaches, yet the summer's complete departure remains just out of reach.

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.
JanFebMarAprMayJunJulAugSepOctNovDec597860101871501871831767993127
Data source: Precipitation data for August generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

August Humidity in Charleston

In August, Charleston experiences an average humidity of 81%, maintaining a level that aligns closely with the previous months of July and February. As summer winds down, this consistent humidity level reflects a subtropical climate that can feel quite sticky at times. Notably, the trend throughout the year showcases higher humidity levels during the winter months, peaking in December at 87% and January at 86%, which emphasizes the area's enduring moisture. Conversely, humidity begins to decline from the intense levels seen in spring and early summer, reaching its annual low of 75% in May and June. As we transition from August to September, humidity climbs slightly again to 83%, marking the return of more humid air as the season shifts. Overall, the persistent humidity of Charleston creates a warm, lush atmosphere that is characteristic of this beautiful Southern city.

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, allowing you to see how August's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec86%81%81%79%75%75%80%81%83%78%85%87%
Data source: Humidity data for August generated using information from the Copernicus Climate Change Service.

August UV Index in Charleston

In August, Charleston experiences an extreme UV Index of 11, keeping the sun-loving residents on alert as their burn time is a brisk 10 minutes. This trend of heightened UV exposure from May through August signifies the peak of summer, where the risk of skin damage is significantly heightened. Following a steady decline from September to December, the UV Index shifts to very high levels, creating a pattern that emphasizes the importance of sun safety, particularly during these sweltering summer months. Whether you're lounging at the beach or enjoying outdoor activities, being mindful of the UV Index is crucial in Charleston. For more detailed information, visit Charleston UV Index.

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.
JanFebMarAprMayJunJulAugSepOctNovDec47910111111119864
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.

August Sunshine in Charleston

August in Charleston shines with 314 hours of glorious sunshine, continuing the warm embrace of summer. This month, while slightly less sun-soaked than July's peak of 341 hours, still stands out for its vibrant days and lingering warmth. Following a steady rise in sun exposure from the early months, the trend shows that the summer months consistently deliver some of the year's best light. As seasons transition and August gives way to the cooler days of fall, the sunlight begins to gradually wane, but the warmth of summer still lingers in the air, inviting residents and visitors alike to enjoy the last rays of the season.

Monthly Sunshine Duration in Charleston: August Highlighted

The August sunshine duration represents the total number of hours Charleston experiences direct sunlight during the month of August, excluding cloudy or obstructed periods. This chart compares the sunshine duration of August with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec186h213h275h306h336h316h341h314h300h288h247h217h
Data source: Charleston August Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Charleston During August

August in Charleston sees a notably lower chance of sunny weather, with the likelihood dropping to a mere 30%. This marks a consistent downward trend from the preceding months, where the probabilities were slightly higher in June (29%) and July (34%). Interestingly, as summer transitions into fall, the sun appears to re-emerge, with September rising sharply to 51% and October maintaining a solid 50% chance. Overall, while August may offer some sun, it tends to be one of the least promising months for sunshine in this Southern coastal city, paving the way for brighter days ahead as the season changes.

Percentage of Sunny Days in August in Charleston

The chart illustrates the percentage of sunny days in Charleston throughout the year, with August highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Charleston experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec45%39%38%56%52%29%34%30%51%50%62%45%
Data source: Charleston August chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Charleston in August

In August, Charleston experiences a delightful 13 hours of daylight, marking a gradual transition as summer winds down. This month showcases a slight decrease from the peak 14 hours recorded in both June and July, reflecting the inevitable approach of fall. The trend throughout the year highlights a significant increase in daylight from 10 hours in January, reaching its zenith in midsummer before beginning to taper off. As the days grow shorter post-August, the contrast between the bright, sun-filled days of summer and the cool, crisp autumn months becomes even more pronounced, inviting residents and visitors alike to savor the lingering warmth of summer evenings.

Average Daylight Hours in Charleston for August

The chart illustrates the variation in daylight duration in Charleston throughout the year, with August highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 14m11h11h 59m13h13h 51m14h 16m14h 2m13h 17m12h 19m11h 19m10h 26m10h
Data source: Charleston daylight hours, calculated by summing the hours between sunrise and sunset for each day.

August Winds in Charleston

In Charleston, August ushers in the calmest winds of the year, with an average speed of just 2.8 m/s (6 mph). This gentle breeze stands out against the backdrop of slightly more vigorous winds earlier in the summer months, where speeds peaked at 4.0 m/s (9 mph) in both March and May. As the summer wanes, wind speeds gradually increase again in September, hinting at the approaching change of seasons. Overall, Charleston experiences its most tranquil wind conditions in August, a transition point that invites residents and visitors to embrace the laid-back charm of the Lowcountry with the softest zephyrs caressing the coastline.

Average August Wind Speed in Charleston

The chart displays monthly wind speed patterns in Charleston, with values for each month shown alongside August's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how August's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.93.84.03.94.03.73.22.8 m/s2.93.23.63.5
Data source: Charleston August wind data, generated using information from the Copernicus Climate Change Service.

How August Weather in Charleston Compares to Other Months

The weather in Charleston changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of August's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Charleston and find detailed weather information for every month.

August and January present stark contrasts in weather conditions. In August, temperatures typically range from a mild 21°C (70°F) to a scorching 35°C (95°F), with an average of 27°C (81°F), coupled with high humidity levels at 81%. This month also sees significant rainfall, with about 183 mm (7.2 in) of precipitation spread over approximately 21 days. In contrast, January experiences much cooler temperatures, with a minimum of -13°C (9°F) and an average of 11°C (52°F), reaching a maximum of 26°C (79°F). January is notably drier, with only 59 mm (2.3 in) of precipitation over 7 days and a slightly higher humidity of 86%. For more details on the weather during this month, check Charleston weather in January.

When comparing the weather in August and February, there is a stark contrast between the two months. August typically sees warm temperatures, with a minimum of 21°C (70°F) and an average of 27°C (81°F), soaring to a maximum of 35°C (95°F). In contrast, February experiences much cooler conditions, with a minimum temperature plummeting to -2°C (29°F) and averaging around 14°C (57°F). While August is characterized by high humidity and considerable rainfall, totaling 183 mm (7.2 inches) over 21 days, February has significantly less precipitation at 78 mm (3.1 inches) across only 9 days. Despite the difference in temperature, both months share the same humidity level of 81%. For more details on February weather, you can visit Charleston weather in February.

August and March present strikingly different weather patterns. August boasts significantly warmer temperatures, with a minimum of 21°C (70°F), an average of 27°C (81°F), and a maximum reaching up to 35°C (95°F). In contrast, March shows a much cooler climate, featuring temperatures that range from a minimum of -1°C (30°F) to a maximum of 28°C (82°F), with an average of 15°C (60°F). Precipitation is notably higher in August, totaling 183 mm (7.2 in) over 21 days, compared to March's 60 mm (2.4 in) over just 6 days. Both months experience high humidity, remaining consistent at 81%. For a more detailed overview of weather conditions during March, you can visit Charleston weather in March.

When comparing the weather in August and April, there's a stark difference in temperatures and precipitation patterns. August boasts much warmer conditions, with average temperatures around 27°C (81°F) and maximums reaching up to 35°C (95°F). In contrast, April experiences cooler temperatures, averaging 19°C (66°F) and peaking at 31°C (89°F). Additionally, August sees significantly more rainfall, with 183 mm (7.2 inches) of precipitation over 21 days, while April has a more moderate 101 mm (4.0 inches) spread over just 8 days. Humidity levels are fairly similar in both months, hovering around 81% in August and 79% in April, contributing to the overall dampness of the warmer month. For more details on the April weather in Charleston, visit Charleston weather in April.

August and May exhibit contrasting weather patterns, highlighting the transition from spring to late summer. In August, temperatures range from a minimum of 21°C (70°F) to a scorching maximum of 35°C (95°F), with an average of 27°C (81°F). The month is also characterized by high humidity at 81% and significant rainfall, totaling 183 mm (7.2 inches) over 21 days. In contrast, May presents a milder climate, with temperatures ranging from a minimum of 9°C (49°F) to a maximum of 37°C (98°F), averaging 23°C (74°F). The precipitation in May is considerably lower at 87 mm (3.4 inches) over just 9 days, and the humidity is slightly less at 75%. For more detailed information, you can check Charleston weather in May.

When comparing the weather in June and August, both months experience similar maximum temperatures, reaching up to 35°C (95°F). However, August tends to be warmer overall, with an average temperature of 27°C (81°F) compared to June's 26°C (79°F). Precipitation levels are higher in August, with 183 mm (7.2 in) over 21 days, while June sees less rain at 150 mm (5.9 in) across 19 days. Additionally, August has a higher humidity level at 81%, compared to June's 75%. For more details about June weather, you can check Charleston weather in June.

In comparing the weather of August and July, we see that both months have quite similar characteristics, with August experiencing slightly warmer temperatures overall. August's average temperature of 27°C (81°F) is just a notch lower than July's average of 28°C (82°F), while the maximum temperatures are also close, with August peaking at 35°C (95°F) compared to July's 34°C (94°F). Precipitation levels are nearly the same, with August recording 183 mm (7.2 in) over 21 days, compared to July's 187 mm (7.4 in) over 20 days. Interestingly, August's humidity sits at 81%, a slight increase from July's 80%. For more specifics on July's weather patterns, you can check out Charleston weather in July.

August typically features warmer temperatures with a minimum of 21°C (70°F) and an average of 27°C (81°F), while September sees a slight drop, with a minimum temperature of 14°C (57°F) and an average of 26°C (78°F). Both months experience high maximum temperatures, peaking at 35°C (95°F) in August and slightly lower at 35°C (94°F) in September. Precipitation levels are relatively similar, with August receiving 183 mm (7.2 in) over 21 days, compared to September's 176 mm (6.9 in) over just 14 days. Additionally, humidity is slightly higher in September at 83%, compared to 81% in August. For more details on September weather patterns, you can check Charleston weather in September.

August and October present quite different weather experiences. In August, temperatures reach a minimum of 21°C (70°F) and soar to an average of 27°C (81°F), with highs peaking at 35°C (95°F). This month is also characterized by significant rainfall, accumulating 183 mm (7.2 in) over 21 days, accompanied by high humidity levels at 81%. In contrast, October offers a milder climate, with minimum temperatures dropping to 3°C (38°F) and an average of 22°C (72°F), reaching a maximum of 31°C (89°F). Rainfall decreases substantially to 79 mm (3.1 in) over just 9 days, and humidity remains relatively comfortable at 78%. For more details on October's climate, visit Charleston weather in October.

August and November present stark differences in weather patterns. In August, temperatures soar with an average of 27°C (81°F), peaking at a sweltering 35°C (95°F), while November offers a much cooler atmosphere with averages around 15°C (59°F) and a maximum of 28°C (84°F). Precipitation is more frequent in August, with 183 mm (7.2 in) over 21 days compared to November’s 92 mm (3.6 in) spread across just 8 days. Humidity remains relatively high in both months, but August sees a slightly lower level at 81% compared to November’s 85%. For a detailed look at November's climate, check out Charleston weather in November.

August and December exhibit starkly contrasting weather patterns. In August, temperatures soar with a minimum of 21°C (70°F) and an average of 27°C (81°F), peaking at a sweltering 35°C (95°F). Humidity is notably high at 81%, accompanied by significant precipitation of 183 mm (7.2 in) over 21 days. In contrast, December brings much cooler temperatures, with a minimum of -3°C (28°F) and an average of 12°C (54°F), reaching a maximum of 25°C (77°F). Although December is drier, with only 127 mm (5.0 in) of rain over 9 days, the humidity remains elevated at 87%. For more details about December weather, you can visit Charleston weather in December.

Compare Charleston's Climate with Cities Worldwide

Conclusion: What to Expect From August Weather in Charleston

August in Charleston brings a distinct blend of warmth and humidity, setting it apart from other months. As temperatures soar, the city experiences its peak heat, with both warmer highs and more frequent rain. The increased precipitation, along with the characteristic humidity, creates a jungle-like atmosphere that envelops the city, making it feel alive and vibrant. While summer's intensity hangs in the air, the lush greenery nourished by the rainfall showcases Charleston's natural beauty. For those looking to understand what to expect, dive deeper into the specifics with our comprehensive guide at Charleston Climate.