December in Athens averages a daily high of 13.7°C with nights around 2.5°C. Expect roughly 10.5 wet days totalling 115.1mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Athens is March–May.
Based on ATHENS BEN EPPS AIRPORT, GA US (4.9km), 1995–2024. 30 years of December data.