December in Oshkosh averages a daily high of 0.1°C with nights around -7.7°C. Expect roughly 9.6 wet days totalling 41mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Oshkosh is May–September.
Based on OSHKOSH, WI US (1.3km), 1995–2024. 30 years of December data.