October in Vacaville averages a daily high of 26.4°C with nights around 9.9°C. Expect roughly 3 wet days totalling 22.7mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Vacaville is April–May.
Based on VACAVILLE NUT TREE AIRPORT ASOS, CA US (3.4km), 1995–2024. 27 years of October data.