August in Peoria averages a daily high of 29.1°C with nights around 18.2°C. Expect roughly 8.3 wet days totalling 86.9mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Peoria is September.
Based on GENERAL WAYNE A. DOWNING INTERNATIONAL AIRPORT, IL US (8.5km), 1995–2024. 30 years of August data.