Weatheo

Seattle Weather by Month

Average temperatures, rainfall and humidity for Seattle, United States, month by month, built from OpenWeather’s historical records. Use it to see what a typical Seattle month looks like before you travel — then check the live Seattle forecast for the days ahead.

Warmest month

July

26°C average high

Coolest month

February

3°C average low

Wettest month

January

141 mm of rain

Driest month

July

16 mm of rain

Average temperature and rainfall in Seattle by month

Averages of the daily highs and lows recorded in each month, with total rainfall, mean humidity and mean wind speed.

MonthAvg highAvg lowRecord low / highRainfallHumidityWind
January8°C3°C-10°C / 15°C
141 mm
85%10 km/h
February9°C3°C-10°C / 18°C
105 mm
82%11 km/h
March12°C5°C-2°C / 26°C
98 mm
77%12 km/h
April15°C6°C1°C / 31°C
75 mm
71%12 km/h
May20°C10°C3°C / 31°C
50 mm
70%10 km/h
June23°C12°C6°C / 42°C
42 mm
68%10 km/h
July26°C14°C9°C / 35°C
16 mm
65%9 km/h
August26°C14°C9°C / 36°C
38 mm
67%9 km/h
September22°C12°C4°C / 32°C
82 mm
74%9 km/h
October16°C9°C-1°C / 30°C
119 mm
82%10 km/h
November11°C5°C-5°C / 21°C
116 mm
84%11 km/h
December8°C3°C-9°C / 15°C
139 mm
86%11 km/h

Best time to visit Seattle

The most comfortable time to visit Seattle is generally June to August, balancing mild daytime temperatures against the driest stretch of the year. The city has a moderate seasonal swing and rain concentrates around January, totalling about 1,021 mm a year.

Travellers who prefer heat should aim for July, when highs average 26°C. January is the month to avoid if rain would spoil your plans — it averages 141 mm, roughly 9× the rainfall of the driest month (July).

Source: OpenWeather historical and statistical weather data. Values are long-term averages, not a forecast — see the Seattle forecast for what is happening now.

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