December in Saint Joseph averages a daily high of 5.5°C with nights around -6°C. Expect roughly 5.6 wet days totalling 30.9mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Saint Joseph is April–May.
Based on ST JOSEPH ROSECRANS MEMORIAL AIRPORT, MO US (5.4km), 1995–2024. 29 years of December data.