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King County · Washington

Seattle, WA weather averages

NOAA climate normals for 1991-2020, measured at Seattle Urban Site, 4.9 km from the city centre — month by month temperature, rain and snow.

Quick answer

Seattle averages a daily high of 61.3°F and a daily low of 45.8°F across the year, with 37.72 inches of precipitation. August is the warmest month at 76.2°F and December the coldest at 36°F.

Average annual high
61.3°FWarmest month August
Average annual low
45.8°FColdest month December
Precipitation per year
37.72 inWettest month December
Snowfall per year
5 in23.1 days at or below 32°F

Seattle weather month by month

Normal daily high and low, precipitation and snowfall for each month, 1991-2020.

MonthHigh °FLow °FPrecip inSnow inRange
January48.637.35.470.937.3 to 48.6 degrees
February51.437.13.520.937.1 to 51.4 degrees
March55.439.73.85039.7 to 55.4 degrees
April59.942.92.79042.9 to 59.9 degrees
May65.848.82.01048.8 to 65.8 degrees
June70.753.31.57053.3 to 70.7 degrees
July75.856.50.85056.5 to 75.8 degrees
August76.2570.94057 to 76.2 degrees
September70.853.11.3053.1 to 70.8 degrees
October60.746.83.38046.8 to 60.7 degrees
November52.440.65.980.740.6 to 52.4 degrees
December46.9366.062.536 to 46.9 degrees

Source: NOAA NCEI, U.S. Climate Normals 1991-2020 — station USW00024281, Seattle Urban Site · rates as published for 1991-2020 normals

How to read Seattle climate normals

What a climate normal is, and what it is not.

A normal is the average of thirty years of daily observations at one station — here Seattle Urban Site, 4.9 km from the centre of Seattle. It describes a typical year, so any single year will run warmer, cooler, wetter or drier. Readings taken at an airport on the edge of town usually sit a degree or two below a dense downtown on summer nights. Seattle sees about 1.6 days a year at or above 90°F and about 92 days with a tenth of an inch of precipitation or more.

Other Seattle data on this site.