May in Gary averages a daily high of 20.4°C with nights around 9.9°C. Expect roughly 12.6 wet days totalling 113.2mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Gary is May–September.
Based on INDIANA DUNES NATIONAL PARK, IN US (21.9km), 1995–2024. 25 years of May data.