Last updated: February 24, 2025
August weather on Sullivan's Island, United States, is marked by warm temperatures and increased humidity. Expect maximum highs around 31°C (89°F) and a comfortable average of 27°C (81°F), with cooler nights averaging 23°C (73°F). However, this picturesque month typically brings significant rainfall, with 197 mm (7.8 in) of precipitation over 21 days, resulting in an 81% humidity level. Visitors should be prepared for brief showers amid the warm coastal atmosphere, making it essential to embrace both the sun and the rain during their stay.
In August, Sullivans Island embraces the peak of summer with temperatures that create a warm, inviting atmosphere. The minimum temperature hovers at a mild 23°C (73°F), making early mornings and evenings pleasantly balmy. This warmth culminates in an average of 27°C (81°F) and a maximum of 31°C (89°F), perfect for beachgoers seeking sun-soaked days. As the month progresses, the coastal breeze offers a refreshing contrast to the heat, reinforcing August as a beloved time for relaxation and exploration along the island's shores. The transition from July’s similar temperatures shows a slight increase, solidifying August as a prime summer month to enjoy all that Sullivans Island has to offer.
In August, Sullivans Island experiences its peak precipitation, accumulating 197 mm (7.8 in) of rain over 21 days, making it the wettest month of the year. This significant increase from July's 171 mm (6.7 in) and 16 days of rain highlights a pattern of heightened rainfall as summer draws to a close. Following a gradual rise throughout the summer months—where June and July also recorded substantial precipitation—August stands out as a time of both temperature and moisture, preparing the landscape for the transitions of early fall. With such frequent rainfall, this month's weather profoundly influences the island's lush vegetation and the vibrant ecosystem that thrives in the humid summer atmosphere.
August in Sullivans Island typically experiences humidity levels of 81%, reflecting a slight dip from the peak of 82% in July. As summer edges toward its close, the humidity remains relatively high, consistent with the coastal climate's traits. This steady humidity pattern from May through September hints at the lingering warmth of summer, with only minor fluctuations. Interestingly, the humidity begins to decrease in the fall months, dropping to 78% in October and stabilizing around 82% in November. Overall, August serves as a transitional month, where the lush, tropical feel of summer gradually gives way to the crisper air of autumn.
In August, Sullivans Island experiences a significant UV Index of 11, categorizing it as extreme exposure. This consistent high level of UV radiation, similar to the peak intensity observed in July, indicates that sun protection is essential, with a burn time of just 10 minutes for unprotected skin. As summer unfolds, the trend showcases a gradual increase from January's moderate UV Index of 4 to the extreme levels of July and August. As the months progress from May to August, inhabitants and visitors should remain vigilant about sun safety, ensuring they are equipped to enjoy the sun while safeguarding their skin. For more detailed information, visit Sullivans Island UV Index.
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August on Sullivans Island is a sun-soaked delight, boasting 321 hours of sunshine—a peak in summer warmth that follows the vibrant July, which recorded 345 hours. The steady decline in daylight hours begins as autumn approaches, but August still shines bright, offering more than enough sunlight to enjoy the beautiful beaches and coastal scenery. With the increase in sunshine from January’s 190 hours to August’s totals, one can appreciate how the months of April through August create a climate perfect for outdoor activities. This consistent trend of increasing sunshine hours ultimately sets the stage for a glorious summer, making Sullivans Island an enticing destination during these warm months. As September rolls in, the days start to shorten, but the lingering warmth of summer is still palpable, allowing for a graceful transition into the cooler seasons.
In August, Sullivans Island experiences a 32% chance of sunny weather, one of the lower probabilities throughout the year. This trend follows a steady decline in sunshine likelihood from the sunnier months of April and May, which boast 57% and 53% chances respectively. As summer progresses, the likelihood dips further, with June and July seeing only 30% and 36% sunny days. While August may not be the most reliable month for sun-seekers, the subsequent September rebounds to a more favorable 52%, hinting that the island's weather can be capricious even in the height of summer.
In Sullivans Island, August marks a transition as daylight begins to wane slightly from the long, sun-filled days of summer. With 13 hours of daylight, August maintains the same generous sunlight as May and April, providing ample time for beachgoers and outdoor enthusiasts to enjoy the warm weather before the gradual decline begins. As the year progresses, daylight hours peak in June and July with 14 hours, showcasing the island's vibrant summer season. Following August, the days shorten steadily, dipping to 12 hours in September, and ultimately wrapping around to 10 hours by November. This trend underscores the island's seasonal rhythm, allowing residents and visitors to savor the lingering summer days while anticipating the cozy, shorter days of fall.
In Sullivan’s Island, August brings a notably gentle breeze, with the average wind speed dipping to 3.9 m/s (9 mph), a decrease from the more robust winds earlier in the summer months. This trend highlights a gradual decline in wind strength as summer transitions into fall, following July's peak of 4.4 m/s (10 mph). The consistent rhythm of the seasons is stark, as winter months typically see a resurgence of wind, with January and March leading the year at 5.2 m/s (12 mph). As the warm summer air lingers, the mellow winds of August invite a relaxed atmosphere, making it a perfect time for leisurely beach outings and serene coastal walks, contrasting the brisk breezes that will soon return.
The weather in Sullivans Island 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 Sullivans Island and find detailed weather information for every month.
The weather in August and January presents a stark contrast, highlighting the seasonal extremes. In August, temperatures range from a mild 23°C (73°F) to a warm 31°C (89°F), accompanied by high humidity at 81% and significant rainfall totaling 197 mm (7.8 in) over 21 days. In contrast, January offers a much cooler experience, with temperatures dipping as low as -5°C (24°F) and averaging around 12°C (53°F), reaching a maximum of 21°C (70°F). Precipitation in January is considerably lower at 66 mm (2.6 in) and occurs over just 8 days, while humidity remains similar at 83%. For a detailed look at what to expect during January, check out Sullivans Island weather in January.
August and February present a striking contrast in weather conditions. While August boasts warm temperatures with a minimum of 23°C (73°F) and an average high of 31°C (89°F), February experiences much cooler temperatures, ranging from a chilly minimum of 2°C (36°F) to a mild maximum of 21°C (70°F). The summer month of August also sees considerable rainfall, averaging 197 mm (7.8 in) over 21 days, coupled with high humidity at 81%. In contrast, February has significantly less precipitation, totaling 91 mm (3.6 in) over just 11 days, while maintaining a slightly lower humidity level of 79%. For more detailed insights, you can check out Sullivans Island weather in February.
The weather in August is characterized by warmer temperatures and higher humidity compared to March. In August, the average temperature reaches a balmy 27°C (81°F), with maximums soaring up to 31°C (89°F), while March sees a much cooler average of 15°C (60°F) and highs of only 23°C (74°F). Additionally, August experiences considerable rainfall, with around 197 mm (7.8 in) spread over 21 days, whereas March has much lighter precipitation at 62 mm (2.4 in) over just 7 days. Despite the slight difference in humidity levels—81% in August and 79% in March—it's clear that August brings more heat and wet conditions compared to the milder, drier weather of March. For more details, you can visit Sullivans Island weather in March.
When comparing the weather in August and April, significant differences emerge in both temperature and precipitation. August tends to be much warmer, with average temperatures ranging from a minimum of 23°C (73°F) to a maximum of 31°C (89°F), while April experiences cooler conditions, with temperatures varying from a minimum of 6°C (42°F) to a maximum of 27°C (81°F). Additionally, August sees higher humidity levels at 81% compared to April's 78%. Precipitation is also notably different; August records a substantial 197 mm (7.8 in) across 21 days, while April is drier, with only 105 mm (4.1 in) over 8 days. For more detailed insights on April weather, you can visit Sullivans Island weather in April.
When comparing the weather in August to that of May, significant differences emerge. August features higher temperatures, with a minimum of 23°C (73°F) and an average of 27°C (81°F), while May sees a cooler minimum of 12°C (55°F) and an average of 23°C (74°F). Both months share a maximum temperature of 31°C (89°F), but August experiences much more rainfall, with 197 mm (7.8 in) across 21 days, in contrast to May’s 82 mm (3.2 in) over just 8 days. Additionally, humidity levels are slightly higher in August at 81%, compared to May’s 78%. For more details, you can check out Sullivans Island weather in May.
In comparing the weather between June and August, we see that August tends to be warmer, with an average temperature of 27°C (81°F) compared to June's 26°C (79°F). However, August also brings more humidity, at 81%, slightly higher than June's 78%. Additionally, August experiences more precipitation, measuring 197 mm (7.8 in) over 21 days, while June records 144 mm (5.7 in) over 17 days. This means that if you're planning outdoor activities, June might offer a slightly drier experience. For more insights, check out the detailed Sullivans Island weather in June.
In comparing the weather between July and August, both months experience a similar average temperature of 27°C (81°F), with August having slightly higher minimum and maximum temperatures (min 23°C/73°F and max 31°C/89°F) compared to July's min of 22°C (72°F) and max of 32°C (89°F). However, August is marked by increased precipitation, totaling 197 mm (7.8 in) over 21 days, compared to July's 171 mm (6.7 in) over 16 days, indicating a wetter month. The humidity levels are also comparable, with August at 81% and July at 82%. For more details about July weather specifically, you can check Sullivans Island weather in July.
August typically presents a warmer climate compared to September, with average temperatures around 27°C (81°F) and peaks reaching up to 31°C (89°F). In contrast, September sees a slight decrease in minimum temperatures, averaging 16°C (61°F), while maintaining a similar average of 26°C (79°F) and occasionally rising to a maximum of 32°C (90°F). Despite both months experiencing high humidity levels of 81%, August is marked by significantly more rainfall—197 mm (7.8 in) over 21 days—while September records slightly less precipitation at 188 mm (7.4 in) over just 14 days. For more detailed insights on September weather, you can check Sullivans Island weather in September.
August and October present strikingly different weather patterns. In August, temperatures are high, with minimums around 23°C (73°F) and maximums reaching 31°C (89°F), alongside significant humidity at 81%. This month also sees considerable rainfall, averaging 197 mm (7.8 in) spread over 21 days, making it one of the wetter months of the year. In contrast, October experiences milder conditions, with minimum temperatures dropping to 7°C (46°F) and maximums reaching 29°C (85°F). The average temperature is a comfortable 23°C (73°F), with much lower precipitation of 85 mm (3.4 in) over just 10 days and humidity slightly lower at 78%. For more detailed insights, visit Sullivans Island weather in October.
August and November present starkly contrasting weather conditions. In August, temperatures are warm, ranging from a minimum of 23°C (73°F) to a maximum of 31°C (89°F), with an average of 27°C (81°F). This month experiences high humidity at 81% and significant precipitation of 197 mm (7.8 in) spread over 21 days, making it feel quite muggy. In contrast, November brings cooler temperatures, with a low of 3°C (38°F) and a high of 26°C (79°F), averaging 16°C (62°F). Although there is still some rainfall, totaling 103 mm (4.1 in) over just 8 days, humidity remains similar at 82%. For more detailed insights on November weather, you can check out Sullivans Island weather in November.
August and December present a stark contrast in weather conditions. In August, temperatures are significantly warmer, ranging from a minimum of 23°C (73°F) to a maximum of 31°C (89°F), with an average of 27°C (81°F). This month experiences high humidity at 81% and considerable precipitation, with 197 mm (7.8 in) falling over 21 days. In contrast, December’s temperatures are much cooler, with a minimum of 0°C (33°F) and an average of 13°C (56°F), peaking at 22°C (72°F). Rainfall is less frequent, accumulating to 141 mm (5.6 in) over just 10 days, while humidity rises slightly to 84%. For a deeper insight into December's climate specifics, visit Sullivans Island weather in December.
As August rolls in, Sullivans Island experiences a noticeable shift in its weather patterns compared to other months. With average temperatures soaring to a warm 27°C (81°F), the island feels particularly humid, complemented by nearly three weeks of precipitation. This humidity, often reaching around 81%, paired with an average of 197 mm of rain, creates a lush atmosphere but can also lead to unpredictable afternoon showers. While summer’s warmth continues, August stands out for its combination of heat and rainfall, reminding visitors to enjoy the outdoor beauty while staying prepared for the elements. For a deeper dive into its unique weather traits, visit Sullivans Island Climate.