October in Naperville averages a daily high of 17.7°C with nights around 6°C. Expect roughly 9.8 wet days totalling 94mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Naperville is August–September.
Based on AURORA WATER, IL US (13.4km), 1995–2024. 30 years of October data.