January in Portage Park averages a daily high of -0.2°C with nights around -7.7°C. Expect roughly 11.2 wet days totalling 51.3mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Portage Park is August–September.
Based on CHICAGO OHARE INTERNATIONAL AIRPORT, IL US (13.8km), 1995–2024. 30 years of January data.