August in Tustin averages a daily high of 30°C with nights around 18.4°C. Rain is rare — about 0.2 wet days and 1.7mm across the month. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Tustin is April–July.
Based on SANTA ANA FIRE STATION, CA US (3.8km), 1995–2024. 30 years of August data.