Last updated: October 30, 2025
September in Goyang-si, South Korea is characterized by a pleasant average temperature of 21°C (71°F), with maximums soaring up to 30°C (86°F) during the day, while cooler nights can drop to around 9°C (48°F). This transitional month brings an average humidity of 77%, making the air feel a bit more muggy. Rainfall is also notable, with 135 mm (5.3 in) of precipitation falling over 9 days, providing much-needed hydration to the lush landscape. Enthusiasts of autumn foliage will delight in the stunning scenery as the month progresses, making it a perfect time to explore this vibrant city.
As September arrives in Goyang-si, South Korea, the weather begins to shift towards a more temperate climate, marking a delightful transition from the sweltering summer months. With temperatures ranging from a pleasant 9°C (48°F) at night to a warm 30°C (86°F) during the day, the average sits at a comfortable 21°C (71°F). This month stands out as a perfect time for outdoor activities, as the oppressive heat of August subsides, creating ideal conditions for enjoying the vibrant autumn foliage. The gradual decline in temperatures heralds the approach of fall, making September a month of both comfort and beauty in Goyang-si, as nature prepares for its next seasonal transformation.
In September, Goyang-si experiences a notable transition in its precipitation patterns, receiving 135 mm (5.3 in) of rainfall over 9 days. This marks a significant drop compared to the preceding months, particularly August, which saw a hefty 262 mm (10.3 in) across 16 days. The month serves as a bridge between the intense summer rains of July and August and the drier conditions of October. Historically, September retains a higher precipitation level than earlier months like January and February, yet it reflects a cooling off from the peak summer downpours. This trend underscores a typical shift towards autumn, where rainfall becomes more moderate but remains essential for replenishing the landscape before the colder months arrive.
In September, Goyang-si experiences a notable dip in humidity, measuring at 77%, which marks a shift from the sweltering heights of 91% seen in both July and August. This decrease signifies the gradual transition from the oppressive summer months, where humidity peaks, to the more temperate autumn season. Interestingly, September's humidity remains elevated compared to the earlier months of the year, such as January and February, where levels hovered around 71% and 65%, respectively. Overall, September’s moderate humidity contributes to a pleasant climate, inviting residents to relish the outdoors before the cooler October settles in with a slight rise to 79%.
In September, Goyang-si experiences a UV Index of 9, marking a return to very high exposure levels after the intense summer months. With a burn time of just 15 minutes, it's clear that sun safety remains paramount as autumn approaches. This trend mirrors the preceding months of July and August, where the UV Index peaked at 11 and the risk was categorized as extreme. As we transition into the fall, the gradual decline in UV intensity, dropping to 6 in October, suggests a welcome reprieve. However, it’s crucial to stay vigilant about sun exposure during this month. For a deeper dive into the UV trends and safety tips, visit Goyang-si UV Index.
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In Goyang-si, South Korea, September basks in a pleasant 262 hours of sunshine, marking a decline from the summer months yet still providing ample light for outdoor activities and exploration. The month begins to transition from the vibrancy of summer, which peaked in June with 317 hours of bright sunshine, gradually tapering off over the following months. September's sunshine hours are a comfortable middle ground between the energetic summer and the cooler, cloudier days of autumn, reflecting a broader trend where daylight gently diminishes. As Goyang-si heads into October, residents can look forward to 263 hours of sunlight, maintaining a similar level, yet hinting at the cozy embrace of fall that awaits.
In Goyang-si, South Korea, the likelihood of sunny weather in September shows a modest 42% chance of sunshine, slightly recovering from the summer months where the probability dips as low as 32% in July and August. This trend suggests a gradual return to brighter skies as the region transitions into autumn, providing a refreshing shift from the typical rainy season. Interestingly, the sunny prospects in September are comparable to those in April and October, which hover around the 43% mark. As the year progresses, the likelihood of sunny days markedly increases in the colder months, reaching 61% in November and peaking at 64% by December, pointing to a seasonal rhythm that many in Goyang-si eagerly anticipate.
As summer transitions to autumn in Goyang-si, South Korea, September ushers in a gentle decline in daylight, with approximately 12 hours of sunlight each day. This marks a noticeable shift from the 14 hours enjoyed during the peak of summer, creating a softer, mellower atmosphere. The gradual reduction in daylight hours, which begins in May, continues its trend downward, ushering in the cooler months of October and November. While the daylight diminishes, the rich hues of early autumn begin to emerge, offering a beautiful backdrop for enjoying the changing seasons amidst the lively urban landscape of Goyang-si.
In September, the winds of Goyang-si begin to gently shift, with an average speed of 2.4 m/s (5 mph), reflecting a subtle transition in the weather as summer fades into autumn. This slight uptick from the calmer August (2.2 m/s) demonstrates a trend where winds usually pick up after the warm summer months, though they remain relatively mild compared to the stronger gusts of early winter. From this data, it's evident that Goyang-si experiences a natural ebb and flow in wind speed throughout the year, with the most vigorous breezes generally observed in the colder months, particularly in January and December. As the days grow shorter and cooler, the September winds serve as a gentle reminder of the changing seasons, inviting residents to enjoy the refreshing outdoor atmosphere before the chill of autumn sets in.
Weather in Goyang-si varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Goyang-si, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather. In September, temperatures range from a cool 9°C (48°F) to a warm 30°C (86°F), with an average of 21°C (71°F). The month experiences considerable rainfall, with 135 mm (5.3 in) of precipitation over about 9 days and a humidity level of 77%. In contrast, January offers a much colder climate, with temperatures dipping as low as -18°C (0°F) and averaging -3°C (27°F), reaching a maximum of 12°C (55°F). Precipitation is minimal at 19 mm (0.7 in) over just 2 days, and humidity is slightly lower at 71%. For a detailed look at January weather conditions, check out Goyang-si weather in January.
September and February present strikingly contrasting weather conditions. In September, temperatures range from a mild 9°C (48°F) at night to a warm 30°C (86°F) during the day, with an average of 21°C (71°F). The month sees considerable rainfall, with 135 mm (5.3 in) occurring over roughly nine days, and humidity levels averaging around 77%. In contrast, February is much colder, with temperatures plummeting to a minimum of -15°C (5°F) and averaging only 0°C (31°F), while the daytime high reaches 17°C (62°F). Precipitation is minimal at 21 mm (0.8 in) over just three days, and humidity is lower at 65%. For more insights on February weather, you can visit Goyang-si weather in February.
September and March weather present a striking contrast, reflecting the transition from late summer to early spring. In September, temperatures can range from a chilly 9°C (48°F) at night to a warm 30°C (86°F) during the day, with an average of 21°C (71°F). This month also sees higher humidity at 77% and significant precipitation, totaling 135 mm (5.3 in) over about 9 days. In contrast, March is much cooler, featuring temperatures that dip as low as -8°C (19°F) at night and reach a maximum of 21°C (69°F) during the day, averaging only 6°C (44°F). The month offers less rainfall, with 43 mm (1.7 in) over about 5 days and lower humidity at 65%. For detailed weather patterns, you can check Goyang-si weather in March.
In September, the weather is notably warmer, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 30°C (86°F), averaging around 21°C (71°F). This month experiences higher precipitation levels, with about 135 mm (5.3 in) falling over 9 days and humidity sitting at 77%. In contrast, April is much cooler, with temperatures fluctuating between a minimum of -2°C (29°F) and a maximum of 28°C (82°F), and an average of 12°C (54°F). Rain is less frequent in April, totaling 52 mm (2.1 in) over 7 days, and the humidity is slightly lower at 75%. For more insights on April weather, you can check Goyang-si weather in April.
September and May present distinct weather patterns, with September showcasing warmer temperatures and higher humidity. In September, temperatures range from a minimum of 9°C (48°F) to a maximum of 30°C (86°F), averaging around 21°C (71°F). The month experiences 135 mm (5.3 in) of precipitation over 9 days, with humidity levels at 77%. In contrast, May has slightly cooler temperatures, with a minimum of 5°C (41°F) and a maximum of 31°C (88°F), averaging 18°C (64°F). The precipitation in May is less, totaling 112 mm (4.4 in) over the same number of days, with humidity at 81%. For more detailed weather insights, you can visit Goyang-si weather in May.
When comparing the weather in September and June, several notable differences emerge. September features a temperature range with a minimum of 9°C (48°F) and a maximum of 30°C (86°F), leading to an average temperature of 21°C (71°F). In contrast, June starts off warmer with a minimum of 12°C (55°F) and reaches a maximum of 35°C (96°F), averaging 22°C (73°F). Additionally, September experiences higher precipitation levels, totaling 135 mm (5.3 in) over 9 days, compared to June's 79 mm (3.1 in) over 8 days. Humidity in June is slightly higher at 85%, while September maintains a humidity level of 77%. For a more detailed look at the conditions in June, you can check out Goyang-si weather in June.
In comparison to July, September offers a noticeably cooler climate, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 30°C (86°F), while July's temperatures are significantly higher, featuring a minimum of 18°C (64°F) and reaching up to 36°C (97°F). The average temperature in September stands at 21°C (71°F), making it more comfortable for outdoor activities compared to July's warmer average of 26°C (79°F). However, September experiences a higher number of rainy days, with around 9 days of precipitation totaling 135 mm (5.3 in), compared to July's 14 days of rain and a total of 217 mm (8.6 in). Additionally, the humidity in July is more intense at 91%, while September's humidity is slightly lower at 77%. For further details, you can check Goyang-si weather in July.
In comparing the weather of September and August, September offers much cooler temperatures, with a minimum of 9°C (48°F) and an average of 21°C (71°F), while August records higher temperatures, peaking at a maximum of 38°C (100°F). August also experiences more days of rainfall, totaling 16 days with 262 mm (10.3 in) of precipitation, compared to September’s 9 days and 135 mm (5.3 in). Moreover, the humidity in August is noticeably higher at 91%, compared to 77% in September, contributing to a more uncomfortable atmosphere in late summer. For a detailed look at August weather, you can visit Goyang-si weather in August.
September and October present distinct shifts in weather patterns. In September, temperatures range from a mild 9°C (48°F) at night to a warm average of 21°C (71°F) during the day, peaking at 30°C (86°F). With 135 mm (5.3 in) of rainfall over 9 days, the month is characterized by a notable level of warmth and humidity at 77%. In contrast, October brings a cooler climate, with nighttime lows dipping to -1°C (30°F) and an average temperature of 14°C (58°F), while daytime highs reach 28°C (83°F). Rainfall decreases significantly to 59 mm (2.3 in) over just 6 days, and humidity slightly rises to 79%. For a detailed overview of October's weather, visit Goyang-si weather in October.
The weather in September marks a notable contrast to that of November. In September, temperatures range from a mild 9°C (48°F) at night to a warm 30°C (86°F) during the day, with an average of 21°C (71°F). The month experiences significant rainfall, totaling 135 mm (5.3 in) over 9 days, coupled with a humidity level of 77%. In stark contrast, November brings much cooler temperatures, with nighttime lows plummeting to -8°C (18°F) and daytime highs reaching a comfortable 21°C (70°F), resulting in an average of just 7°C (44°F). Precipitation is significantly lower in November, at 47 mm (1.8 in) over only 5 days, and humidity slightly increases to 80%. For more details about the weather specifics, you can refer to Goyang-si weather in November.
In September, the weather is generally warm and pleasant, with average temperatures around 21°C (71°F) and peaks reaching up to 30°C (86°F). The month sees significant rainfall, totaling 135 mm (5.3 in) over approximately 9 days, and humidity levels remain high at 77%. In contrast, December brings a stark drop in temperatures, with averages sinking to -1°C (31°F) and lows plummeting to -16°C (4°F). Although precipitation is much lower, totaling only 20 mm (0.8 in) over about 4 days, humidity decreases slightly to 74%. For more detailed weather information, check Goyang-si weather in December.
As summer transitions to autumn, September in Goyang-si showcases a beautiful blend of warm days and cooler evenings. The average temperature hovers comfortably around 21°C, offering a pleasant escape from the intense heat of July and August. While the month still experiences occasional rainfall, totaling about 135 mm over nine days, it feels less oppressive than the summer downpours. The increased humidity at 77% serves as a reminder of the lingering summer, yet the dip in minimum temperatures down to 9°C introduces a refreshing change. This unique weather pattern makes September a delightful period for both locals and visitors to enjoy the stunning scenery of Goyang-si. For more insights into the climate, check out Goyang-si Climate.