September weather forecast
South Korea

September ushers in the autumn season in South Korea, a period marked by gradually cooling temperatures and a decrease in humidity. In Seoul, the average temperatures range from 16°C (60.8°F) to 26°C (78.8°F), while Busan experiences slightly warmer conditions, with average temperatures between 19°C (66.2°F) and 26°C (78.8°F).

Rainfall continues to decrease in September, with an average of about 150mm (5.91"). The majority of this rainfall typically occurs in the first half of the month, with the latter half seeing a considerable reduction in precipitation and humidity, leading to clear, crisp days.

In comparison to August, September brings cooler temperatures, less rainfall, and reduced humidity, providing a welcome respite from the intensity of the summer season. The changing foliage, from lush green to vibrant hues of red and yellow, begins to signal the onset of the full autumn season. As the country moves into October, these autumnal conditions become more pronounced, with further reductions in temperature and increasingly vibrant fall colors.

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• Seoul - September »
  In Seoul during September, the rain falls for 9.1 days and regularly aggregates up to 169mm (6.65") of precipitation. In Seoul the average relative humidity in September is 69.2%.
• Busan - September »
  In Busan in September, it is raining for 9.1 days, with typically 69mm (2.72") of accumulated precipitation. September brings a gradual cooling trend to Busan, with temperatures dropping from August highs to a comfortable 24.5°C (76.1°F).
• Incheon - September »
  In Incheon during September, the rain falls for 8.2 days and regularly aggregates up to 154mm (6.06") of precipitation. In Incheon, in September, during 8.2 rainfall days, 154mm (6.06") of precipitation is typically accumulated.
• Daegu - September »
  In Daegu, South Korea, in September, during 10.6 rainfall days, 71mm (2.8") of precipitation is typically accumulated. On the first day of September in Daegu sunrise is at 05:57 and sunset at 18:53.
• Daejeon - September »
  On the last day of September, in Daejeon, sunrise is at 06:24 and sunset at 18:15 KST. In Daejeon, in September, during 11.8 rainfall days, 82mm (3.23") of precipitation is typically accumulated.
• Gwangju - September »
  In Gwangju, South Korea, in September, during 9.5 rainfall days, 40mm (1.57") of precipitation is typically accumulated. On the first day of September in Gwangju, sunrise is at 06:05 and sunset at 18:59.
• Ulsan - September »
  In Ulsan, during September, the rain falls for 13.2 days and regularly aggregates up to 124mm (4.88") of precipitation. In Ulsan, in September, the average water temperature is 24.1°C (75.4°F).
• Suwon - September »
  In Suwon, during September, the rain falls for 8.7 days and regularly aggregates up to 154mm (6.06") of precipitation. In Suwon, during September, the rain falls for 8.7 days and regularly aggregates up to 154mm (6.06") of precipitation.
• Goyang - September »
  In Goyang, in September, the average water temperature is 21.9°C (71.4°F). In Goyang, the average seawater temperature in September is 21.9°C (71.4°F).
• Gumi - September »
  On the first day of September in Gumi sunrise is at 05:58 and sunset at 18:54. On the first day of September in Gumi, sunrise is at 05:58 and sunset at 18:54.