April in Indianapolis averages a daily high of 17.9°C with nights around 6.3°C. Expect roughly 11.8 wet days totalling 110.5mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Indianapolis is September–October.
Based on INDIANAPOLIS INTERNATIONAL AIRPORT, IN US (12.5km), 1995–2024. 30 years of April data.