September in Olympia averages a daily high of 22.3°C with nights around 8.1°C. Expect roughly 8.6 wet days totalling 55.1mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Olympia is July–August.
Based on OLYMPIA AIRPORT, WA US (7.9km), 1995–2024. 30 years of September data.