July in Champaign averages a daily high of 29.6°C with nights around 18.4°C. Expect roughly 10 wet days totalling 107mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Champaign is September.
Based on CHAMPAIGN 3 S, IL US (3.6km), 1995–2024. 30 years of July data.