October in Arlington Heights averages a daily high of 17.1°C with nights around 6.8°C. Expect roughly 10.8 wet days totalling 79.3mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Arlington Heights is May–September.
Based on CHICAGO PALWAUKEE AIRPORT, IL US (7.2km), 1995–2024. 27 years of October data.