January in La Mesa averages a daily high of 21.1°C with nights around 6°C. Expect roughly 6 wet days totalling 59.3mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit La Mesa is March–June.
Based on EL CAJON, CA US (9.6km), 1995–2024. 28 years of January data.