Seattle weather by month › September
Seattle in September: weather and what to expect
It’s fine, but not the best. June and August are more pleasant.
September weather in Seattle
Daytime high70°F 21°C
Night low52°F 11°C
Rain1.6 in 40 mm
AirComfortable
SunModerate sun
In September, Seattle averages highs of 70°F (21°C) and lows of 52°F (11°C), with 1.6 in (40 mm) of rain. The air feels comfortable and the sun is moderate. 1991–2020 averages, not a forecast.
Pack: light layers, a sweater for evenings.
Places with the same weather in September
Match out of 100 for September, one city per country.
Jan · Feb · Mar · Apr · May · Jun · Jul · Aug · Sep · Oct · Nov · Dec