December in Decatur averages a daily high of 12.6°C with nights around 1.8°C. Expect roughly 10.4 wet days totalling 153.3mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Decatur is April–May.
Based on DECATUR 4 SE, AL US (5.6km), 1995–2024. 23 years of December data.