May in Renton averages a daily high of 19°C with nights around 9.4°C. Expect roughly 10.6 wet days totalling 43.7mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Renton is July–August.
Based on RENTON MUNICIPAL AIRPORT, WA US (1.4km), 1995–2024. 26 years of May data.