Seoul in December (2026): Weather, Christmas Lights, Winter Festivals and New Year's Eve
December is when Seoul switches on. Department stores wrap their buildings in light shows, a lantern festival fills the Cheonggyecheon stream, Gwanghwamun Square turns into a winter market, and the year ends with the bell at Bosingak and a countdown in Myeongdong. It is also properly cold: this is the month when Seoul’s average low drops below freezing. This guide covers the weather in real numbers, what to wear, and what is on in Seoul in December 2026. Because some events announce their dates late, we have marked which dates are confirmed for 2026 and which are based on last year , so you can tell what is safe to plan around. December in Seoul at a glance • Average high 4.2°C (40°F) , average low −3.4°C (26°F) • Dry: about 23 mm of precipitation over roughly 4 days, and about 6 days with some snow • Sunset around 5:15 p.m. , sunrise after 7:30 a.m. • Christmas Day (Friday, December 25, 2026) is a public holiday; New Year’s Day (Friday, January 1, 2027) too How cold is it r...