Last updated: October 30, 2025
September in Yongsan, South Korea, offers a blend of mild temperatures and moderate rainfall. With maximum temperatures reaching up to 30°C (87°F) and an average of 21°C (70°F), the month provides a comfortable climate for outdoor activities. However, the weather can turn quite variable, with a minimum plunge to 10°C (50°F) at night. Expect 182 mm (7.2 inches) of precipitation spread over approximately 10 days, contributing to a fairly humid atmosphere at 77%. This combination of warmth and moisture fosters lush greenery, making September a beautiful time to experience the vibrant landscapes of Yongsan.
In September, Yongsan, South Korea, experiences a delightful transition from the sweltering summer into the gently cooling embrace of autumn. With minimum temperatures averaging around 10°C (50°F) and maximums peaking at 30°C (87°F), the month delivers a comfortable average temperature of 21°C (70°F). This seasonal shift is marked by a gradual decline in heat, following August's sultry days, making September an ideal time for outdoor exploration. Visitors can enjoy pleasant weather, highlighted by longer daylight hours, which encourage leisurely strolls through parks and vibrant street markets. As the leaves start to change, the crispness in the air offers a refreshing reminder that autumn is on its way.
In September, Yongsan, South Korea experiences a remarkable transition as the monsoon recedes, yielding a total precipitation of 182 mm (7.2 in) over 10 rainy days. This marks a significant decrease from the heavier rainfall of August, which recorded 229 mm (9.0 in) across the same number of days. The lingering effects of summer are still evident, yet September's rainfall reflects a gradual shift towards drier months, with precipitation levels dropping substantially from the peak July and August figures. As the season changes, residents can anticipate a refreshing shift in the air, often accompanied by lingering clouds and crisp breezes, setting the stage for autumn's arrival.
As summer transitions to autumn, September in Yongsan, South Korea, offers a slight reprieve from the intense humidity of July and August, which peak at a sweltering 91%. With the arrival of September, humidity levels drop to a more comfortable 77%, signaling the end of the muggy summer months. This decrease not only makes the early fall more enjoyable but also highlights a gradual trend of fluctuating humidity throughout the year. Following September, humidity slightly rises again in October, reaching 78%, but the overall trend indicates a shift towards drier conditions as the year winds down. The annual cycle clearly shows elevated humidity from late spring through the summer, making September a refreshing month for those seeking relief before the onset of the cooler autumn air.
As September unfolds in Yongsan, South Korea, residents and visitors experience a very high UV Index of 10, indicating that while the sun is still strong, it’s slightly less intense than the peak summer months. With a recommended burn time of just 15 minutes, the urgency for sun protection remains critical. This trend mirrors the previous months of June through August, where exposure levels reached an extreme peak, especially in August with an index of 12. The gradual decline in UV levels from summer to early autumn signifies a shift towards more moderate exposure, yet vigilance is still advisable. For ongoing updates and insights, visit Yongsan UV Index. Keep your skin protected as you enjoy the beautiful early fall days!
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As summer gently fades into autumn, September in Yongsan, South Korea, offers a charming transition with 243 hours of sunshine. This month, though slightly less radiant than the vibrant summer peak of 303 hours in May, still boasts ample light, allowing for lingering outdoor activities. Interestingly, the sunshine hours gradually decline from the blue-skied exuberance of summer, with a noticeable dip from July's 265 hours to September's more moderate warmth. However, this decline is accompanied by the crisp, refreshing air of fall, making September an ideal time for exploration and enjoyment of the city's beautiful parks and cultural sites. Embracing the balance of warmth and brightness, Yongsan's September serves as a gentle reminder of the season’s fleeting splendor.
In Yongsan, South Korea, September brings a 36% chance of sunny weather, marking a slight improvement over the summer months where sunshine dips to 25% in July and 27% in August. This gradual increase hints at a more hopeful transition into autumn, although it's still below the city’s annual peak later in the year. As the days grow shorter and temperatures cool, the chance of encountering clear skies starts to align with the more favorable odds seen in the fall and winter months, particularly as October offers a more promising 50% chance of sun. Overall, while September may not guarantee abundant sunshine, it represents a subtle shift towards brighter days ahead.
As summer wanes, September in Yongsan, South Korea, offers a gentle transition with 12 hours of daylight, starting to hint at the approaching autumn. This month marks a gradual decrease from the vibrant, sun-drenched days of July and August, each boasting a full 14 hours of daylight. Historically, daylight duration begins its descent after the peak of summer, and by September, the sunlight gently recedes, providing a perfect backdrop for the shifting colors of the season while still ensuring ample time for outdoor activities. As daylight hours continue to dwindle into October, reflecting this rhythmic pattern, nature prepares for the cozy embrace of fall.
As September sweeps into Yongsan, South Korea, the winds begin to pick up slightly with an average speed of 2.8 m/s (6 mph), a refreshing contrast to the calm summer months. This increase from August’s gentle breezes of 1.9 m/s heralds the transition into autumn, invigorating the air as the city's vibrant colors start to emerge. Throughout the year, Yongsan experiences its peak windiness in the late fall, with wind speeds rising again in November to 2.6 m/s. However, September holds a sweet spot—it's not just a prelude to the gustier days ahead but also a time when the warmth of summer lingers, making it perfect for outdoor explorations. As the days grow shorter and the temperatures begin to cool, the September winds signify change, inviting both locals and visitors to embrace the beauty of the season.
Weather in Yongsan varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Yongsan, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present starkly contrasting weather patterns. In September, temperatures range from a minimum of 10°C (50°F) to a maximum of 30°C (87°F), with an average of 21°C (70°F). This month also sees significant rainfall, with about 182 mm (7.2 in) of precipitation over approximately 10 days, accompanied by relatively high humidity at 77%. In sharp contrast, January experiences much colder temperatures, ranging from a minimum of -20°C (-4°F) to a maximum of 13°C (55°F), with an average of -1°C (30°F). Precipitation drops significantly to only 25 mm (1.0 in) over just 4 days, and the humidity is slightly lower at 71%. For a more detailed look at January weather, you can visit Yongsan weather in January.
September and February present striking contrasts in weather. In September, temperatures range from a minimum of 10°C (50°F) to a maximum of 30°C (87°F), with an average of 21°C (70°F), creating a warm and humid atmosphere with 182 mm (7.2 in) of precipitation over about 10 days. In contrast, February experiences much colder conditions, with temperatures dipping as low as -15°C (5°F) and averaging only 1°C (34°F), yet reaching highs of 22°C (71°F). Additionally, February sees significantly less precipitation, with only 34 mm (1.3 in) falling over approximately 4 days, and a lower humidity level of 66%. For more specific insights on February weather, you can refer to Yongsan weather in February.
September and March present distinctly different weather patterns. In September, temperatures range from a mild 10°C (50°F) at night to a warm 30°C (87°F) during the day, with an average temperature of 21°C (70°F). This month also sees considerable rainfall, with 182 mm (7.2 in) of precipitation over approximately 10 days and a high humidity level of 77%. In contrast, March experiences much cooler conditions, with nighttime temperatures dropping to -5°C (23°F) and daytime highs reaching 24°C (75°F), averaging at 8°C (46°F). Precipitation is significantly lower in March, totaling 65 mm (2.5 in) over 8 days, and the humidity is reduced to 64%. For further details on March weather, check out Yongsan weather in March.
The weather in September is notably warmer than in April, with average temperatures reaching 21°C (70°F) compared to April's 13°C (55°F). September experiences a wider temperature range, peaking at a maximum of 30°C (87°F), while April can reach a maximum of 29°C (85°F). In terms of precipitation, September sees significantly more rain, with 182 mm (7.2 in) over approximately 10 days, while April has just 69 mm (2.7 in) spread over around 6 days. Both months have relatively high humidity levels, but September is slightly more humid at 77% compared to April's 74%. For a detailed look at the specific weather conditions in April, you can visit Yongsan weather in April.
When comparing the weather in September and May, September tends to be warmer overall, with average temperatures reaching 21°C (70°F) compared to May's 18°C (65°F). Interestingly, while September has a higher maximum temperature of 30°C (87°F), both months experience relatively similar maximums, with May peaking at 31°C (89°F). Precipitation levels are notably different, as September sees 182 mm (7.2 in) over 10 days, whereas May has only 82 mm (3.2 in) over 8 days, indicating September is the wetter month. Humidity levels are comparable, with September at 77% and May slightly higher at 79%. For a closer look at May weather conditions, you can check Yongsan weather in May.
In comparing the weather between September and June, we observe some notable differences. September generally experiences slightly lower temperatures, with averages around 21°C (70°F) compared to June's average of 22°C (73°F). While both months have similar minimum temperatures, June can reach higher maximums, peaking at 34°C (94°F) versus September’s 30°C (87°F). Precipitation is more pronounced in September, totaling 182 mm (7.2 in) over roughly 10 days, whereas June sees less rainfall, accumulating 102 mm (4.0 in) in about 8 days. Humidity levels are relatively high in both months, with September at 77% and June slightly higher at 82%. For a more detailed look at June weather, check out Yongsan weather in June.
When comparing the weather in September and July, one can observe notable differences in temperature and precipitation. September features a wider temperature range, with minimum temperatures dropping to 10°C (50°F) and maximums reaching up to 30°C (87°F), while the average temperature stands at a comfortable 21°C (70°F). In contrast, July is warmer, with minimum temperatures starting at 17°C (62°F) and peaking at a scorching 36°C (98°F), and an average temperature of 25°C (78°F). However, July also sees higher humidity at 91% and more rainfall, accumulating 222 mm (8.8 in) over 16 rainy days compared to September's 182 mm (7.2 in) over just 10 days. For a more detailed look at July weather, visit Yongsan weather in July.
In comparing the weather of September and August, September generally experiences a notable drop in temperature, with minimums around 10°C (50°F) compared to August's warmer 16°C (60°F). The average temperature in September is 21°C (70°F), which is significantly cooler than August's average of 26°C (79°F). Additionally, September tends to see slightly less precipitation at 182 mm (7.2 in) over 10 days, while August has a higher precipitation amount of 229 mm (9.0 in) across 16 days. Humidity levels are also elevated in August at 91%, compared to September's 77%. For a detailed view of the weather in August, check out Yongsan weather in August.
In September, the weather tends to be warmer and wetter, with average temperatures ranging from a minimum of 10°C (50°F) to a maximum of 30°C (87°F) and precipitation reaching 182 mm (7.2 in) over about 10 days. In contrast, October experiences a significant drop in average temperature to around 14°C (58°F), with minimum temperatures dipping to 0°C (32°F) despite the maximum reaching 31°C (88°F). Precipitation decreases notably to 73 mm (2.9 in) over just 6 days, and humidity remains quite consistent at 78%. For more information about the weather in October, you can visit Yongsan weather in October.
September and November present stark contrasts in weather patterns. In September, temperatures range from a mild 10°C (50°F) at night to a warm 30°C (87°F) during the day, with an average of 21°C (70°F). This month also experiences significant rainfall, with 182 mm (7.2 in) over about 10 days, contributing to a humidity level of 77%. In contrast, November sees a significant drop in temperatures, with nightly lows plunging to -5°C (23°F) and daytime highs reaching only up to 21°C (70°F), resulting in an average temperature of just 8°C (46°F). Additionally, November is considerably drier, with only 31 mm (1.2 in) of precipitation over about 5 days, coupled with a slightly higher humidity level of 80%. For more details on November weather in Yongsan, visit Yongsan weather in November.
September and December present stark contrasts in weather. In September, temperatures range from a mild 10°C (50°F) at night to a warm 30°C (87°F) during the day, with an average temperature of 21°C (70°F). This month also sees considerable rainfall of 182 mm (7.2 in) over about 10 days, contributing to a humidity level of 77%. In contrast, December brings a much chillier climate, with temperatures dropping to a minimum of -13°C (8°F) and averaging just 1°C (33°F). The maximum temperature reaches only 15°C (59°F), and precipitation is significantly lower at 24 mm (1.0 in) over just 3 days, with humidity slightly decreased at 76%. For more detailed information, check out Yongsan weather in December.
As we transition into September, Yongsan’s weather begins to showcase a delightful mix of warmth and refreshing coolness, distinguishing it from the sweltering summer months. With average temperatures settling comfortably at around 21°C (70°F), the days are still pleasantly warm, reaching up to 30°C (87°F), while the nights invite a cooler ambiance ideal for cozy evenings. This month also sees an increase in humidity at 77%, accompanied by 182 mm of rain spread over 10 days, making September a transitional period filled with bursts of refreshing showers that breathe life into the autumn season. For a more detailed look at Yongsan’s climate patterns throughout the year, check out Yongsan Climate.