September in Federal Way averages a daily high of 21.6°C with nights around 12°C. Expect roughly 7.7 wet days totalling 44.2mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Federal Way is July–September.
Based on TACOMA NUMBER 1, WA US (11.2km), 1995–2024. 26 years of September data.