Weather In Korea September 2024. In this south korea guide, i cover everything you need to know for an amazing south korea trip (not related to a specific month) from basic information about. In september in south korea, the average air temperature ranges from 26 °c (79 °f) during the day to 20 °c (68 °f) at night.

In gangneung in september, the average. Daily high temperatures decrease by 8°f, from 81°f to 73°f, rarely falling below 66°f or exceeding 86°f.