South Korea Weather December 2025. In this photo provided by south korea presidential office, south korean president yoon suk yeol speaks during a press briefing at the presidential office in seoul, south korea,. Jeju in december has very similar weather to busan, with average temperatures ranging from 5°c | 42°f and 11°c | 52°f.
In seoul, in december, it is raining for 7.4 days,. 30 mm (1 inch) in busan;