December in Carlsbad averages a daily high of 19.1°C with nights around 4.4°C. Expect roughly 6.9 wet days totalling 48.5mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Carlsbad is April–October.
Based on OCEANSIDE MUNICIPAL AIRPORT, CA US (6.8km), 1995–2024. 26 years of December data.