December in Gatchina averages a daily high of -2°C with nights around -6.8°C. Expect roughly 20.6 wet days totalling 56.4mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Gatchina is May–August.
Based on BELOGORKA, RS (19.7km), 1995–2024. 23 years of December data.