December in Santa Monica averages a daily high of 18.7°C with nights around 9°C. Expect roughly 6.4 wet days totalling 61.2mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Santa Monica is April–November.
Based on SANTA MONICA MUNICIPAL AIRPORT, CA US (4.1km), 1995–2024. 25 years of December data.