October in Wheaton averages a daily high of 17.2°C with nights around 5.5°C. Expect roughly 10.8 wet days totalling 78.6mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Wheaton is May–June.
Based on CHICAGO WEST CHICAGO DUPAGE AIRPORT, IL US (12.4km), 1995–2024. 28 years of October data.