December in Uppsala averages a daily high of 1.3°C with nights around -3.5°C. Expect roughly 14.5 wet days totalling 44.8mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Uppsala is May–September.
Based on UPPSALA AUT, SW (0.5km), 1995–2024. 30 years of December data.