December in Helong averages a daily high of -4.7°C with nights around -15.6°C. Rain is rare — about 2.7 wet days and 4.2mm across the month. A hard month to visit for comfort alone.
Across the year, the best time to visit Helong is May.
Based on YANJI, CH (54.9km), 1995–2024. 26 years of December data.