March in Sunnyvale averages a daily high of 18.5°C with nights around 8.2°C. Expect roughly 10.2 wet days totalling 45.4mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Sunnyvale is May–October.
Based on MOFFETT FEDERAL AIRFIELD, CA US (4.2km), 1995–2024. 20 years of March data.