Last updated: October 30, 2025
September in Yongsan-dong, South Korea presents a delightful blend of warm temperatures and occasional rainfall. With maximum daily highs reaching 31°C (88°F) and an average of 21°C (70°F), the weather is generally conducive to outdoor activities. However, expect the cooler touch of the season, as temperatures can dip to a minimum of 10°C (50°F). The month sees a sizable precipitation total of 133 mm (5.2 in) spread over 9 days, contributing to a humid environment with levels around 77%. Travelers and locals alike should prepare for a mix of sunshine and refreshing rain, making September a unique month to experience in Yongsan-dong.
In September, Yongsan-dong experiences a delightful transition as the summer heat gives way to milder temperatures. With minimums around 10°C (50°F) and averages climbing to 21°C (70°F), the month offers comfort reminiscent of early fall. The peak temperatures can reach up to 31°C (88°F), maintaining a warm ambiance that encourages outdoor activities. This trend marks a shift from the scorching summer highs, while still embracing the warmth that defines late summer. As the days grow shorter, September stands out as a pleasant month, perfectly blending the tail end of summer with the serene onset of autumn.
In September, Yongsan-dong experiences a noticeable shift in its precipitation patterns, receiving 133 mm (5.2 in) of rainfall over 9 days. While this marks a decline from the record highs of the previous two months—July and August, which saw an impressive 252 mm (9.9 in) and 269 mm (10.6 in) respectively—September still delivers a substantial amount of rain, suggesting the lingering effects of the summer monsoon season. This moderate rainfall is a stark contrast to the drier months ahead, with October's average dropping to just 63 mm (2.5 in). Overall, September serves as a transitional month, balancing the tail end of summer's wetness with the onset of autumn's cooler, drier conditions.
As summer fades, September in Yongsan-dong offers a slight reprieve from the oppressive humidity that characterizes the peak months of July and August, both averaging a high of 91%. In September, humidity drops to 77%, signaling a transition as autumn approaches. This decrease brings a welcome comfort after the sweltering summer, yet it still remains noticeably high compared to the earlier months of the year—where humidity levels hovered around 65% in winter and early spring. As the year progresses into October, Yongsan-dong retains a relatively humid environment with levels at 79%, but September marks a distinct turn as the city prepares for the milder, drier days of fall.
As summer transitions into autumn, September in Yongsan-dong, South Korea, continues to showcase a significant UV Index of 9, categorized as very high, with a burn time of just 15 minutes. This marks a slight decrease from the extreme levels of July and August, which had UV Index values peaking at 11. Despite this reduction, September's intensity still highlights the need for protective measures against UV exposure. Visitors and residents alike should remain vigilant, ensuring they apply sunscreen and wear protective clothing when outdoors. For more detailed information on UV trends throughout the year, check out the comprehensive guide on Yongsan-dong UV Index.
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As September unfurls in Yongsan-dong, South Korea, the city basks in 262 hours of sunshine, marking a gentle decline from the sun-soaked highs of summer. With the peak of June at 317 hours, the daylight gradually tapers as autumn approaches, yet September still offers a warm embrace of sunlit days. This month showcases a comfortable balance, serving as a transition from the 311 hours of May and the lush vibrancy of the preceding summer months. The sun's descent invites a cozy ambiance, making it an ideal time to explore the vibrant streets of Yongsan-dong, where the fading sunlight dances across the bustling scenery.
In Yongsan-dong, South Korea, the likelihood of sunny weather in September reflects a slight resurgence after the typical summer months, with a 41% chance of sunshine. This marks a gentle uptick compared to the peak summer months of July and August, which both see a 30% chance of clear skies. As the region transitions into autumn, September offers a reprieve from the summer humidity, positioning itself between the fading summer and the clearer skies of October, which sees a 43% probability of sun. This trend suggests that while not the sunniest month, September in Yongsan-dong can still surprise with beautiful, sunny days, making it an appealing time to enjoy outdoor activities before the chill of winter sets in.
As the summer months gradually fade, September in Yongsan-dong, South Korea, brings a gentle transition in daylight, offering about 12 hours of sunlight. This marks a slight decrease from the peak of 14 hours seen during the vibrant months of June through August. While daylight starts to wane, the month still retains a significant amount of light compared to the earlier winter months, creating a balanced blend of warmth and coolness. Following the lively scenes of summer, September serves as a reminder of the approaching autumn, with daylight durations continuing to decline until they settle at 9 hours by December. This rhythmic change in daylight not only shapes the daily activities of residents but also enhances the beauty of Yongsan-dong as it transitions into fall.
In Yongsan-dong, South Korea, the September wind offers a gentle caress with an average speed of 2.4 m/s (5 mph), marking a slight uptick from the languid breezes of summer. This subtle increase reflects a gradual transition toward the brisker winds of autumn. From January to August, the wind speeds consistently hovered between 1.8 m/s and 3.1 m/s, with the summer months experiencing the calmest conditions. September's refreshing gusts herald the changing seasons, as the wind begins to mirror the vibrant rhythm of falling leaves and cooler temperatures, while the average wind speed remains steady as it continues into October. The overall trend indicates a comforting consistency, weaving the serene whispers of Yongsan-dong’s landscape into the fabric of daily life.
Weather in Yongsan-dong varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Yongsan-dong, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather. September boasts a mild temperature range, with minimums of 10°C (50°F) and maximums reaching up to 31°C (88°F), averaging around 21°C (70°F). This month is characterized by significant rainfall, totaling 133 mm (5.2 in) over 9 days, and a humidity level of 77%, creating a warm and often humid atmosphere. In contrast, January experiences frigid conditions, with temperatures plunging to a minimum of -18°C (1°F) and a maximum of just 13°C (55°F), averaging -2°C (28°F). Precipitation is minimal, at 19 mm (0.8 in) over just 2 days, and the humidity is lower at 71%, resulting in a dry and cold winter month. For a detailed look at Yongsan-dong's January weather, check out Yongsan-dong weather in January.
September and February present stark contrasts in weather conditions. In September, temperatures range from a pleasant 10°C (50°F) at night to a warm 31°C (88°F) during the day, with an average of 21°C (70°F). The month is relatively humid, at 77%, and experiences significant rainfall, totaling 133 mm (5.2 in) over about 9 days. In sharp contrast, February's climate is much colder, with temperatures dipping as low as -14°C (7°F) and peaking at 18°C (65°F), averaging around 0°C (32°F). Precipitation is minimal in February, at just 22 mm (0.8 in) over 4 days, and the humidity is lower, at 65%. For more details, you can check Yongsan-dong weather in February.
September and March present strikingly different weather conditions. In September, temperatures are mild to warm, ranging from a minimum of 10°C (50°F) to a maximum of 31°C (88°F), with an average of 21°C (70°F). The month experiences considerable rainfall, with 133 mm (5.2 in) over about 9 days and a high humidity level of 77%. In contrast, March is much cooler, featuring temperatures that range from a minimum of -7°C (20°F) to a maximum of 21°C (70°F), with an average of only 7°C (44°F). Precipitation is lower in March, at 46 mm (1.8 in) spread over 5 days, and humidity sits at a more comfortable 65%. For a detailed look at March weather, check out Yongsan-dong weather in March.
September and April present contrasting weather characteristics. In September, temperatures range from a cool 10°C (50°F) at night to a warm 31°C (88°F) during the day, with an average of 21°C (70°F). The month typically sees 133 mm (5.2 in) of rain over about 9 days, and humidity levels are relatively high at 77%. In contrast, April experiences much cooler temperatures, with lows of 0°C (32°F) and highs reaching 28°C (82°F), averaging at 12°C (54°F). Precipitation is significantly lower at 55 mm (2.2 in) over 6 days, and humidity is slightly less at 75%. For more detailed weather insights during April, you can check Yongsan-dong weather in April.
In comparing the weather of September and May, we see noticeable differences in temperature and precipitation. September typically has a warmer average temperature of 21°C (70°F) compared to May's cooler average of 18°C (64°F). However, May can reach a slightly higher maximum temperature of 32°C (89°F), while September's maximum is 31°C (88°F). Both months experience approximately 9 days of precipitation, but September has a marginally higher total rainfall at 133 mm (5.2 in) versus May's 111 mm (4.4 in). Humidity levels are also slightly elevated in May at 81%, compared to September's 77%. For a closer look at conditions in May, you can visit Yongsan-dong weather in May.
In September, the weather tends to be slightly cooler compared to June, with average temperatures ranging from a minimum of 10°C (50°F) to a maximum of 31°C (88°F), while June sees temperatures ranging from 12°C (54°F) to a hotter 35°C (94°F). Although September has higher precipitation levels at 133 mm (5.2 in) over 9 days, June is not far behind with 86 mm (3.4 in) over 8 days. Additionally, September's humidity is a bit lower at 77%, compared to June's humidity of 85%. For more specific details on June weather, you can visit Yongsan-dong weather in June.
In comparing the weather of September and July, it’s evident that July tends to be hotter and more humid. July features a minimum temperature of 18°C (64°F) and an average of 26°C (79°F), with maximums reaching 36°C (97°F). In contrast, September has a cooler minimum of 10°C (50°F) and an average temperature of 21°C (70°F), peaking at 31°C (88°F). Additionally, July experiences more precipitation, with 252 mm (9.9 in) over 15 days, compared to September's 133 mm (5.2 in) over 9 days. This results in a significantly higher humidity level in July at 91% versus September’s 77%. For more details on July weather, you can visit Yongsan-dong weather in July.
August typically presents warmer and more humid conditions compared to September, with average temperatures reaching up to 26°C (80°F) and rare maximums of 38°C (101°F). In contrast, September experiences a more moderate climate, with an average temperature of 21°C (70°F) and maximums of 31°C (88°F). August also sees higher precipitation levels, totaling 269 mm (10.6 in) over approximately 16 days, while September has significantly lower rainfall at 133 mm (5.2 in) across 9 days, resulting in a shift toward drier weather. For a closer look at the August weather patterns, you can check this link: Yongsan-dong weather in August.
In September, the weather is considerably warmer, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 31°C (88°F), averaging around 21°C (70°F). It experiences higher humidity at 77% and more precipitation, totaling 133 mm (5.2 in) over 9 days. In contrast, October sees a notable drop in temperature, with a minimum of 0°C (32°F) and an average of 14°C (58°F), while the maximum reaches 28°C (83°F). The month is drier, with only 63 mm (2.5 in) of rain over 6 days and slightly increased humidity at 79%. For more detailed information on October weather, check Yongsan-dong weather in October.
In September, the weather tends to be much warmer and more humid, with temperatures ranging from a pleasant 10°C (50°F) at night to a maximum of 31°C (88°F) during the day, and an average of 21°C (70°F). However, it also sees significant rainfall, with 133 mm (5.2 in) of precipitation over roughly 9 days. In contrast, November experiences a dramatic shift in climate, with cooler temperatures ranging from a minimum of -7°C (21°F) to a maximum of 21°C (70°F) and an average of only 7°C (45°F). Precipitation decreases to 54 mm (2.1 in) over just 5 days, while humidity slightly rises to 80%. For a closer look at how November weather unfolds in this region, you can visit Yongsan-dong weather in November.
September and December are strikingly different in terms of weather. In September, temperatures average around 21°C (70°F), with highs reaching up to 31°C (88°F) and a relatively humid atmosphere at 77%. The month sees a significant amount of rainfall, with 133 mm (5.2 in) of precipitation spread over 9 days. In contrast, December experiences much colder temperatures, averaging -1°C (31°F) and peaking at only 12°C (54°F). The precipitation is minimal, totaling just 22 mm (0.9 in) over 4 days, and humidity levels drop slightly to 74%. For more detailed information, you can check Yongsan-dong weather in December.
As September unfolds in Yongsan-dong, residents experience a vibrant transition from the sweltering summer heat to more temperate conditions. Unlike the scorching peaks of August, September offers a delightful average temperature that invites outdoor activities, yet still showcases a maximum warmth that hints at the lingering summer sun. This month sees a modest amount of rainfall, refreshing the landscape while the humidity remains notably high, creating a lush atmosphere. With nine days of precipitation, September offers a balanced climate, setting the stage for the crisp autumn days ahead. For a deeper understanding of the local weather patterns, explore Yongsan-dong Climate.