May in Tarneit averages a daily high of 17.1°C with nights around 8.1°C. Expect roughly 9.3 wet days totalling 35.7mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Tarneit is November–April.
Based on LAVERTON RAAF, AS (8.8km), 1995–2024. 30 years of May data.