June in St. Louis averages a daily high of 30°C with nights around 19.9°C. Expect roughly 9.5 wet days totalling 122.3mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit St. Louis is April–May.
Based on ST LOUIS SCIENCE CENTER, MO US (6.3km), 1995–2024. 20 years of June data.