Seattle Weather October 2025. With october's onset, the weather shows a temperature decrease, transitioning from an agreeable 69.6°f (20.9°c) in september to a moderate 58.6°f (14.8°c). Weather.com brings you the most accurate monthly weather forecast for seattle, wa with average/record and high/low temperatures, precipitation and more.

When it comes to the weather in seattle, october brings the greatest change out of any month of the year. Weather.com brings you the most accurate monthly weather forecast for seattle, wa with average/record and high/low temperatures, precipitation and more.