December in Oak Lawn averages a daily high of 3.3°C with nights around -3.8°C. Expect roughly 10.8 wet days totalling 61mm. A hard month to visit for comfort alone.
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 December data.