August in Oak Lawn averages a daily high of 28.4°C with nights around 19.4°C. Expect roughly 9.2 wet days totalling 102.7mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Oak Lawn is August–September.
Based on CHICAGO MIDWAY AIRPORT 3 SW, IL US (3.3km), 1995–2024. 30 years of August data.