May in Round Rock averages a daily high of 29.6°C with nights around 17.9°C. Expect roughly 9.1 wet days totalling 133mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Round Rock is February–April.
Based on AUSTIN GREAT HILLS, TX US (13.4km), 1995–2024. 17 years of May data.