September Weather in Gwangju, South Korea

Last updated: October 30, 2025

In September, Gwangju, South Korea, experiences a delightful transition into autumn, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 30°C (86°F), resulting in an average of 21°C (70°F). This month boasts a total precipitation of 142 mm (5.6 in) over approximately 9 days, contributing to the city's lush landscapes. With an average humidity level of 77%, mornings can feel particularly refreshing, making September an inviting time for outdoor activities and exploration in this vibrant city.

September Temperature in Gwangju

In September, Gwangju, South Korea, enjoys a delightful transition from the sweltering summer months to the crispness of autumn. With minimum temperatures averaging around 9°C (48°F) and delightful afternoons reaching a pleasant 30°C (86°F), the city experiences comfortable days that invite outdoor exploration. The average temperature settles at 21°C (70°F), creating a perfect climate for enjoying the vibrant fall foliage that begins to emerge. As the heat recedes from the heights of summer—where August boasted scorching maximums of 38°C (100°F)September offers a refreshing reprieve that showcases Gwangju's seasonal beauty and charm, making it an ideal time for visitors to enjoy the city’s cultural and natural attractions.

September Weather in Gwangju: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Gwangju, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Gwangju, September typically has an average temperature of 21°C (70°F), with highs reaching up to 30°C (86°F) and lows dropping to around 9°C (48°F).
JanFebMarAprMayJunJulAugSepOctNovDec273144546372787969574430
Data source: Temperature data for Gwangju generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Gwangju

September in Gwangju, South Korea, sees a notable shift in precipitation, with 142 mm (5.6 in) of rain falling over 9 days. This marks a significant decrease from the heavy downpours of the preceding months—July and August recorded 278 mm (10.9 in) and 285 mm (11.2 in), respectively. As summer transitions to autumn, the rainfall begins to taper off, yet September still holds its own as one of the wetter months of the year. This period serves as a refreshing reprieve from the sweltering heat, while the abundant rainfall nourishes the lush landscapes of Gwangju, preparing the region for the drier months ahead.

September Precipitation Trends in Gwangju

The chart displays monthly precipitation patterns in Gwangju, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Gwangju, September typically receives around 142 mm (5.6 inches) of precipitation spread over approximately 9 days.
JanFebMarAprMayJunJulAugSepOctNovDec2224536711794278285142655623
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Gwangju

In September, Gwangju, South Korea, experiences a noticeable shift in humidity as it begins to decline from the peak summer levels. The average humidity for the month stands at 77%, which is significantly lower than the tropical-like conditions of 91% experienced in both July and August. This reduction marks a transition into autumn, where the weather starts to become more comfortable. Throughout the year, humidity in Gwangju fluctuates, starting at 71% in January, peaking during the summer months, and then tapering off as the cooler months approach. September serves as a bridge, hinting at the upcoming autumn with more moderate humidity levels, while still retaining a hint of the lingering summer warmth.

September Average Humidity in Gwangju

This chart illustrates the average monthly humidity levels in Gwangju, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Gwangju is approximately 77%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec71%65%65%75%81%85%91%91%77%79%80%74%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Gwangju

In September, Gwangju, South Korea experiences a very high UV Index of 9, requiring just 15 minutes of unprotected sun exposure before risking a burn. This trend follows an intense summer where July and August peaked at an extreme index of 11, emphasizing the need for caution during outdoor activities. As the seasons transition into autumn, the UV Index begins to dip, reverting to high levels in October. However, the persistent very high reading in September highlights the lingering strength of the sun, reminding residents and visitors alike to stay vigilant and protect their skin. For more information, visit the Gwangju UV Index.

Maximum UV Index Levels in Gwangju for September

The chart shows the monthly maximum UV Index (UVI) for Gwangju in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Gwangju typically reaches 9, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec346891011119643
Data source: Gwangju September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Gwangju

September in Gwangju, South Korea, showcases a delightful transition from the vibrant summer months, with the city basking in 256 hours of sunshine. This abundant sunlight reflects a gradual decline from the bright peaks of summer, notably May and June, which recorded 305 and 310 hours respectively. As the days shorten and autumn approaches, the sunshine hours dip, but September still offers a warm embrace of light, reminding us of the lingering warmth of summer. Interestingly, this month stands as a gentle precursor to October, which maintains a similar brightness with 257 hours. Overall, September acts as a bridge, blending the lively energy of the summer sun with the crispness of fall.

Monthly Sunshine Duration in Gwangju: September Highlighted

The September sunshine duration represents the total number of hours Gwangju experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec198h240h277h282h305h310h283h275h256h257h229h234h
Data source: Gwangju September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Gwangju During September

In Gwangju, South Korea, the likelihood of sunny weather shows a fascinating trend as the year progresses. September records a 39% chance of sunshine, reflecting a slight increase from the mid-summer months when the probability dips to 29%. This suggests a shift towards clearer skies as the oppressive heat of summer wanes. Notably, the sunny prospects continue to rise into the fall, with October boasting a 42% chance, further hinting at a delightful transition as the seasons change. While September may not guarantee endless sunshine, it offers a hopeful reprieve from the summer gloom, inviting residents and visitors alike to embrace the charm of early autumn in this vibrant city.

Percentage of Sunny Days in September in Gwangju

The chart illustrates the percentage of sunny days in Gwangju throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Gwangju experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec57%55%44%44%36%34%30%29%39%42%57%65%
Data source: Gwangju September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Gwangju in September

As September arrives in Gwangju, South Korea, the city experiences a gradual transition towards shorter days, with 12 hours of daylight illuminating the landscape. This decrease follows the peak of summer, where June through August basked in a consistent 14 hours of sunlight, encouraging outdoor activities and a vibrant social scene. The month of September serves as a gentle reminder of the upcoming autumn, as daylight subtly tapers off, leading to a cozy ambiance. Following the September shift, daylight will continue to dwindle, reaching 11 hours in October and further descending into the winter months. This rhythmic pattern of daylight not only marks the changing seasons but also shapes the lifestyle and activities of Gwangju's residents throughout the year.

Average Daylight Hours in Gwangju for September

The chart illustrates the variation in daylight duration in Gwangju throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 53m10h 47m11h 57m13h 9m14h 10m14h 41m14h 25m13h 32m12h 23m11h 11m10h 9m9h 36m
Data source: Gwangju daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Gwangju

In September, Gwangju, South Korea, experiences a gentle breeze with an average wind speed of 2.2 m/s (5 mph), marking a slight increase from the summer months' calm airflow. This uptick continues the trend of gradual wind revival after the quieter summer, where July and August recorded their mildest speeds, averaging only 1.7 m/s and 2.0 m/s, respectively. As autumn approaches, these subtle shifts in wind provide a refreshing contrast to the stillness of summer, foreshadowing the invigorating winds of the months to come. Notably, September's winds are a prelude to October’s return to 2.0 m/s, showcasing Gwangju's transition into a season where the air feels a bit crisper, inviting exploration and outdoor enjoyment.

Average September Wind Speed in Gwangju

The chart displays monthly wind speed patterns in Gwangju, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec2.72.92.42.52.51.91.72.02.2 m/s2.02.32.5
Data source: Gwangju September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Gwangju Compares to Other Months

Weather in Gwangju varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Gwangju, focusing on differences in temperature, rainfall, humidity, and UV levels.

September and January present strikingly different weather experiences. In September, temperatures range from a mild minimum of 9°C (48°F) to a warm average of 21°C (70°F), peaking at a maximum of 30°C (86°F). This month is marked by higher humidity at 77%, and precipitation is more frequent, with rain on about 9 days, totaling 142 mm (5.6 in). In contrast, January is characterized by frigid temperatures, with a minimum of -19°C (-2°F) and an average of -3°C (28°F), only rising to a maximum of 12°C (54°F). The winter month sees significantly lower precipitation at just 22 mm (0.9 in) over 2 days and slightly lower humidity at 71%. For more detailed insights, check out Gwangju weather in January.

September and February present stark contrasts in weather patterns. September features a warmer climate with temperatures ranging from a cool 9°C (48°F) to a hot 30°C (86°F) and an average of 21°C (70°F). It also experiences significant rainfall, with 142 mm (5.6 in) over 9 days, contributing to a higher humidity of 77%. In contrast, February is characterized by much colder temperatures, ranging from a frigid -15°C (6°F) to a mild 18°C (65°F), averaging around 0°C (32°F). Precipitation is minimal at just 24 mm (0.9 in) over 4 days, and the humidity is lower at 65%. For more detailed insights on February weather, you can refer to Gwangju weather in February.

In comparing the weather between September and March, it's clear that September offers significantly warmer temperatures, with an average of 21°C (70°F) and highs that can reach up to 30°C (86°F). In contrast, March experiences much cooler conditions, with average temperatures around 6°C (44°F) and lows plummeting to -7°C (20°F). Additionally, September is characterized by higher humidity levels at 77%, along with more precipitation, accumulating to 142 mm (5.6 in) over about nine days. March, however, sees less rainfall at 53 mm (2.1 in) and lower humidity at 65%, making for drier conditions. For a more detailed look at what to expect, you can check out Gwangju weather in March.

In comparing the weather between September and April, we can see notable differences in temperature and precipitation. September typically experiences a wider temperature range, with minimums around 9°C (48°F) and maximums soaring up to 30°C (86°F), leading to an average of 21°C (70°F). In contrast, April starts off chillier, with minimum temperatures dropping to -1°C (30°F) and averaging 12°C (54°F), while reaching a maximum of 27°C (81°F). Additionally, September sees higher precipitation levels, with 142 mm (5.6 in) over 9 days, compared to April's 67 mm (2.7 in) over just 6 days. The humidity remains relatively high in both months, at 77% in September and 75% in April. For more details on April weather, you can visit Gwangju weather in April.

In September, temperatures range from a cool 9°C (48°F) at night to a warm 30°C (86°F) during the day, with an average temperature of 21°C (70°F). This month experiences more rainfall, totaling 142 mm (5.6 in) over 9 days and maintaining a humidity level of 77%. In contrast, May is slightly cooler with minimum temperatures of 5°C (41°F) and an average of 17°C (64°F), while daytime highs can reach 32°C (90°F). May's precipitation is somewhat less at 117 mm (4.6 in) over the same number of rainy days, and humidity is slightly higher at 81%. For a detailed look at May weather, you can check Gwangju weather in May.

In comparing the weather between September and June, September tends to be slightly cooler with average temperatures ranging from a minimum of 9°C (48°F) to a maximum of 30°C (86°F), while June sees higher temperatures ranging from a minimum of 12°C (54°F) to a maximum of 34°C (94°F). Additionally, September experiences more precipitation, with 142 mm (5.6 in) over 9 days, compared to June's 94 mm (3.7 in) over the same number of days. The humidity levels are also quite high in both months, with September at 77% and June even higher at 85%. For more detailed information about June weather, you can visit Gwangju weather in June.

September weather is generally milder than July, featuring a minimum temperature of 9°C (48°F) and an average of 21°C (70°F), with a maximum that can reach up to 30°C (86°F). In contrast, July experiences warmer conditions, with minimum temperatures starting at 17°C (63°F) and an average of 25°C (78°F), peaking at 35°C (96°F). Rainfall also distinguishes the two months; September sees 142 mm (5.6 in) of precipitation over 9 days, whereas July is much wetter, accumulating 278 mm (10.9 in) over 15 days, contributing to a humidity level of 91%. For more detailed information on July weather, you can refer to Gwangju weather in July.

In comparing the weather of September to August, September experiences a noticeable drop in temperature, with minimums around 9°C (48°F) and averages reaching 21°C (70°F), in contrast to August’s minimum of 15°C (59°F) and average of 26°C (79°F). While August can be quite hot, peaking at 38°C (100°F), September's maximum temperature is more moderate at 30°C (86°F). Additionally, September sees a significant decrease in precipitation, receiving 142 mm (5.6 in) over 9 days compared to August's 285 mm (11.2 in) across 17 days, resulting in a less humid atmosphere, with September's humidity at 77% compared to August's 91%. For more detailed information, check out Gwangju weather in August.

The weather in September is characterized by warmer temperatures, with a minimum of 9°C (48°F) and an average high of 30°C (86°F), making it feel quite summer-like for a good part of the month. However, it also brings considerable rainfall, totaling 142 mm (5.6 in) over 9 days and a humidity level of 77%. In contrast, October experiences a significant drop in temperatures, with a minimum of -1°C (30°F) and an average high of 28°C (83°F), indicating the onset of autumn. The month sees much less precipitation, with only 65 mm (2.5 in) over 6 days, and slightly higher humidity at 79%. For more details, you can check out Gwangju weather in October.

September and November present strikingly different 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 (70°F). This month also experiences considerable rainfall, totaling 142 mm (5.6 in) over 9 days, while humidity hovers around 77%. In contrast, November sees a pronounced drop in temperatures, with nighttime lows plummeting to -7°C (20°F) and daytime highs reaching a maximum of 20°C (69°F), averaging just 7°C (44°F). Precipitation decreases significantly to 56 mm (2.2 in) over 5 days, coupled with a slightly higher humidity level of 80%. For more detailed information, you can check Gwangju weather in November.

September and December present strikingly different weather patterns. 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 (70°F). This month also experiences significant rainfall, totaling 142 mm (5.6 in) over about 9 days, paired with high humidity at 77%. In contrast, December brings a much colder climate, with temperatures dropping significantly, featuring a minimum of -16°C (4°F) and an average of -1°C (31°F), peaking at 12°C (54°F). Precipitation is notably lower at 23 mm (0.9 in) over just 4 days, and humidity decreases slightly to 74%. For more details, check out Gwangju weather in December.

Compare Gwangju's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Gwangju

As summer transitions into fall, September in Gwangju offers a refreshing escape from the heat, with average temperatures settling comfortably around 21°C. Unlike the sweltering months preceding it, this month experiences a notable decrease in maximum temperatures, while the evenings can feel quite cool, dipping to as low as 9°C. Though precipitation remains significant, with about nine rainy days, the air feels consistently humid, averaging 77%. This combination of milder temperatures and increased rainfall makes September a unique and transitional month, perfect for outdoor activities amid the changing scenery. For a deeper understanding of the region's climate patterns throughout the year, visit Gwangju Climate.