January in Wŏnsan averages a daily high of 2.2°C with nights around -5.7°C. Rain is rare — about 2 wet days and 1.6mm across the month. A hard month to visit for comfort alone.
Across the year, the best time to visit Wŏnsan is September–October.
Based on WONSAN, KN (3.5km), 1995–2024. 21 years of January data.