Last updated: February 24, 2025
September weather on James Island, United States is characterized by warm temperatures and moderate humidity. With a maximum temperature soaring to 35°C (94°F) and an average of 26°C (78°F), the island enjoys a tropical feel, perfect for outdoor activities. However, the month also brings about considerable rainfall, totaling 176 mm (6.9 in) over 14 days, which contributes to the lush scenery. Coupled with high humidity levels at 83%, visitors can expect a mix of sunny and wet days, making it essential to stay prepared for changing weather conditions while exploring the beauty of this coastal paradise.
As September rolls in, James Island experiences a delightful shift in temperatures, signaling the transition from summer to early autumn. The month showcases a minimum temperature of 14°C (57°F), providing a refreshing coolness compared to the previous sweltering summer months. With an average of 26°C (78°F), the days remain pleasantly warm, enticing residents and visitors to enjoy the outdoors. However, temperatures can still peak at a maximum of 35°C (94°F), reminiscent of August’s heat, creating a comforting overlap of seasonal warmth. This blend of cooler mornings and toasty afternoons cultivates a vibrant atmosphere perfect for enjoying the island's natural beauty while basking in the tail end of the summer sun.
In September, James Island experiences a significant precipitation level of 176 mm (6.9 in), contributing to a trend of increased rainfall as the summer months transition into fall. This month's rainfall occurs over 14 days, marking a slight decrease in precipitation frequency from August, which saw 21 rainy days. The uptick in September precipitation, while lower than July and August's peaks of 187 mm (7.4 in) and 183 mm (7.2 in), signals a steady rhythm of moisture that nourishes the region as it heads into the drier season. Overall, this pattern highlights a notable peak in the summer months, with September maintaining a robust rainfall level that enhances the lush landscape characteristic of the island.
In September, James Island experiences a slight increase in humidity, averaging 83%. This marks a continuation of the summer's warm, moist conditions, following July and August, where humidity levels hovered around 80%. As autumn approaches, the humidity remains relatively high, reflecting the coastal climate's lingering warmth before it steadily declines in October. Notably, this month transitions from the summer's peak humidity, yet it remains noticeably higher than the drier months of late fall and winter, hinting at the region's characteristic climate variations. Overall, September serves as a bridge between summer's sultry embrace and the cooler, more comfortable days of fall, making it a vibrant time for the island's lush landscapes.
As September rolls around in James Island, the UV Index remains impressively high at 9, indicating a very high exposure category. Following the intense summer months, where the UV levels peaked at 11, there's a slight dip but still enough intensity to warrant caution. With a burn time of just 15 minutes, it's essential to protect your skin, even as the days start to cool. This trend of elevated UV levels continues into October, suggesting that while summer may be over, UV protection remains crucial in early autumn. For those planning outdoor activities, staying informed about the local UV Index is vital; you can find more details here: James Island UV Index.
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As summer gently transitions into fall, September shines brightly in James Island, boasting 300 hours of sunlight—a delightful peak before the cooler months set in. This month captures the essence of late summer, following a vibrant July with 341 hours, while gracefully tapering off from the sun-drenched heights of May and June. The warm rays of September seem to linger a bit longer, offering a comforting embrace as the days start to shorten. While the sunshine begins its gradual decline into the fall and winter months, with October showing 288 hours, September stands out as a radiant conclusion to the sun-soaked season, inviting residents and visitors alike to savor the beauty of the outdoors.
September on James Island ushers in a noticeable upswing in sunny weather, with a 51% chance of sunshine that marks a significant improvement compared to the summer months. Following the generally gloomy skies of June, July, and August, where chances plummet to as low as 29%, September presents a welcome reprieve. The likelihood of sun in this month hovers just above October's 50%, capturing the essence of fall while still embracing the lingering warmth of summer. As the seasons transition, the chance of bright days returns to a more favorable level, making September an ideal time to enjoy the outdoors before the cooler months set in.
As summer transitions into fall on James Island, September experiences a gentle decline in daylight, with about 12 hours of sun each day. This marks a gradual shift from the longer, sun-soaked days of July and August, which each basked in 14 hours of daylight. Following the peak of summer, the daylight begins to taper off, signaling the approach of cooler seasons. October continues this trend, offering slightly less light at 11 hours, while the shorter days of winter loom ahead. This rhythm of daylight underscores the island’s dynamic seasonal changes, inviting locals and visitors alike to savor every sunlit moment before the darker days set in.
As summer fades into autumn in James Island, September ushers in a gentle breeze with an average wind speed of 2.9 m/s (6 mph). This marks a subtle decline from the previous months, reflecting a summer lull that sees winds become noticeably lighter, particularly when compared to the peaks of March and May, both at 4.0 m/s (9 mph). The shift to cooler temperatures is palpable as the winds begin to pick up again in October with a slight increase to 3.2 m/s (7 mph). This downward trend in wind speed throughout the summer months, culminating in September, highlights the island's transition from the exuberance of summer to the calm of fall, inviting residents and visitors alike to enjoy the serene ambiance of this coastal gem.
The weather in James Island changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in James Island and find detailed weather information for every month.
September and January present stark contrasts in weather patterns. In September, temperatures range from a mild 14°C (57°F) at night to a sweltering 35°C (94°F) during the day, with high humidity levels at 83% and considerable rainfall of 176 mm (6.9 in) over about 14 days. In contrast, January experiences much cooler temperatures, with night lows plunging to -13°C (9°F) and daytime highs reaching a mild 26°C (79°F), while precipitation is significantly lower at 59 mm (2.3 in) over just 7 days. The humidity remains high at 86%, but the overall climate is far more frigid than in September. For more detailed insights, you can check James Island weather in January.
In September, the weather is characterized by warm temperatures with a minimum of 14°C (57°F) and an average of 26°C (78°F), reaching a high of 35°C (94°F). This month also experiences a significant amount of rainfall, totaling 176 mm (6.9 in) over 14 days, and maintains a high humidity level of 83%. In contrast, February brings much cooler temperatures, with a minimum of -2°C (29°F) and an average of 14°C (57°F), peaking at 26°C (79°F). Precipitation is notably lower at 78 mm (3.1 in) over just 9 days, with a slightly lower humidity of 81%. For more details on the January conditions, check out James Island weather in February.
September and March exhibit distinct weather patterns, highlighting the transition from summer to autumn and winter to spring, respectively. In September, temperatures soar with a minimum of 14°C (57°F) and an average high of 26°C (78°F), peaking at a scorching 35°C (94°F). This month also receives significant rainfall, accumulating 176 mm (6.9 in) over approximately 14 days, coupled with high humidity levels at 83%.
In contrast, March presents a much cooler climate with a minimum temperature of -1°C (30°F) and an average high of 15°C (60°F), reaching up to 28°C (82°F) at its peak. Precipitation is considerably lower, totaling 60 mm (2.4 in) over about 6 days, while humidity remains relatively stable at 81%.
For more details on the weather patterns, you can check James Island weather in March.
September presents a warm and humid climate, with average temperatures ranging from a minimum of 14°C (57°F) to a maximum of 35°C (94°F). The month typically experiences substantial rainfall, totaling 176 mm (6.9 in) over about 14 days, contributing to its high humidity of 83%. In contrast, April offers a more temperate experience, with average temperatures between 4°C (39°F) and 31°C (89°F), and a much lower precipitation level of 101 mm (4.0 in) spread over only 8 days. Furthermore, April's humidity is slightly lower at 79%, making it a more comfortable month overall. For detailed insights, you can check out James Island weather in April.
When comparing the weather of September and May, a few notable differences emerge. In September, the temperatures range from a milder minimum of 14°C (57°F) to a warm maximum of 35°C (94°F), with an average temperature of 26°C (78°F). In contrast, May sees slightly cooler temperatures, with a minimum of 9°C (49°F) and a maximum that can reach up to 37°C (98°F), averaging around 23°C (74°F). Additionally, September experiences higher humidity at 83% compared to May’s 75%, and it also sees significantly more rainfall, with 176 mm (6.9 in) over 14 days compared to May's 87 mm (3.4 in) over 9 days. For more insights, you can visit James Island weather in May.
In comparing the weather in September and June, both months feature similar average temperatures, hovering around 26°C (79°F), though September experiences slightly cooler minimum temperatures at 14°C (57°F) compared to June’s minimum of 16°C (61°F). Interestingly, both months can reach maximum temperatures of 35°C (95°F), indicating similar peak heat levels. However, September tends to be wetter, with 176 mm (6.9 in) of precipitation over 14 days, while June has 150 mm (5.9 in) spread across 19 days. Additionally, September has higher humidity at 83%, compared to June's 75%. For more insights into June weather patterns, you can visit James Island weather in June.
When comparing the weather between September and July, several key differences emerge. September experiences a broader temperature range, with minimums dipping to 14°C (57°F) while still reaching a maximum of 35°C (94°F), resulting in an average of 26°C (78°F). In contrast, July showcases a warmer minimum of 20°C (69°F) and an average temperature of 28°C (82°F), peaking at 34°C (94°F). Precipitation levels are slightly higher in July, totaling 187 mm (7.4 in) over 20 days compared to September's 176 mm (6.9 in) across 14 days. Humidity levels are also comparable, with September at 83% and July at 80%. For a closer look at July's climate specifics, check out James Island weather in July.
In comparing the weather of September and August, September experiences slightly lower minimum temperatures, averaging around 14°C (57°F) compared to August's minimum of 21°C (70°F). The average temperature in September is 26°C (78°F), which is just a notch below August's average of 27°C (81°F). Both months share similar maximum temperatures, peaking at 35°C (95°F) in August and 35°C (94°F) in September. August has higher precipitation levels at 183 mm (7.2 in) over 21 days, while September records 176 mm (6.9 in) across 14 days, indicating a slightly drier month. Humidity levels remain relatively close, with September at 83% and August at 81%. For those interested in more details, check out James Island weather in August.
September and October exhibit notable differences in weather patterns, marking a transition from the warm late summer months into the cooler autumn season. In September, temperatures range from a minimum of 14°C (57°F) to a maximum of 35°C (94°F), with an average temperature of 26°C (78°F). The month is also characterized by higher humidity at 83% and significant precipitation totaling 176 mm (6.9 in) over 14 days. In contrast, October brings cooler temperatures, with a minimum of 3°C (38°F), an average of 22°C (72°F), and a maximum of 31°C (89°F). Rainfall decreases to 79 mm (3.1 in) over just 9 days, and humidity drops slightly to 78%. For more details, you can check James Island weather in October.
September and November present a striking contrast in weather. September boasts warmer temperatures, with minimums around 14°C (57°F) and maximums peaking at 35°C (94°F), making it significantly hotter than November, where temperatures range from a chilly -1°C (31°F) at night to a pleasant 28°C (84°F) during the day. Additionally, September experiences higher precipitation levels, accumulating 176 mm (6.9 in) over 14 days, whereas November sees less rain, totaling 92 mm (3.6 in) across just 8 days. Humidity levels remain relatively similar, with September at 83% and November slightly higher at 85%. For more detailed information, check out James Island weather in November.
September weather is characterized by warm temperatures, with a minimum of 14°C (57°F), averaging 26°C (78°F), and peaking at a hot 35°C (94°F). The month experiences significant rainfall, totaling 176 mm (6.9 in) over about 14 days, accompanied by high humidity at 83%. In contrast, December brings much cooler conditions, with temperatures ranging from a minimum of -3°C (28°F) to a maximum of 25°C (77°F) and an average of 12°C (54°F). Precipitation is lower in December at 127 mm (5.0 in) over 9 days, while humidity remains relatively high at 87%. For more on December weather specifics, visit James Island weather in December.
In September, James Island presents a unique blend of warmth and humidity that sets it apart from other months. With temperatures reaching up to 35°C and an average of 26°C, this transitional period ushers in a feeling of summer's end while also hinting at the cooler days ahead. Rain becomes more frequent, with 14 days experiencing precipitation, contributing to a noticeable increase in humidity at 83%. This combination can create a lush, tropical atmosphere, making it a vibrant time to experience the island's natural beauty. To dive deeper into the climatic nuances throughout the year, visit James Island Climate.