Seattle (WA) monthly weather averages

Contents

Average daytime temperature

The bar chart below shows the average monthly peak daytime temperatures at Seattle

Seattle average temperature chart (Celsius) Seattle average temperature chart (Fahrenheit)
Average monthly temperatures in Seattle (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 7.2 9.9 11.7 14.1 17.8 20.9 23.5 23.5 20.5 15.5 10.4 7.5
°F 44.9 49.9 53 57.3 64 69.6 74.4 74.3 68.8 59.8 50.7 45.5

Please note: these are the average peak daytime temperatures (usually around mid-afternoon) so do not show daytime / night highs and lows. To see the daily range of temperatures have a look at the temperature max / min chart below.

Average rainfall & rainy days

The graph below shows the average rainfall and number of rainy days per month.

Seattle monthly rainfall chart (mm) Seattle monthly rainfall chart (inches)
Average monthly rainfall in Seattle (mm and inches)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
mm 149 105 95 66 46 41 21 31 49 87 150 151
inches 5.9 4.1 3.7 2.6 1.8 1.6 0.8 1.2 1.9 3.4 5.9 5.9
Rainy days 18 15 16 13 11 8 5 6 9 12 17 18

Average annual rainfall in Seattle: 914.633mm (360.1 inches)

Average daily sunshine

The bar chart below shows the average daily sunshine hours in Seattle

Seattle average daily sunshine chart
Average daily sunshine Seattle
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Hrs sunshine 2.5 4.1 5.9 7.2 8.6 9.4 10.8 9.8 7.8 5 2.7 2

Day / night temperatures

The graph below shows the daily range of temperatures for each month.

Seattle average minimum / maximum temperatures (Celsius) Seattle average minimum / maximum temperatures (Fahrenheit)
Maximum and minimum daily temperatures in Seattle (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Min °C 1.7 2.9 3.6 5.1 8 11.1 12.8 13.1 10.9 7.6 4.5 2.4
Max °C 7.3 10.1 11.9 14.3 18 21.2 23.8 23.8 20.7 15.7 10.6 7.7
Min °F 35.1 37.2 38.4 41.2 46.4 51.9 55 55.5 51.6 45.6 40 36.2
Max °F 40.1 43.7 45.9 49.5 55.4 61 64.9 65.1 60.4 52.9 45.5 41

Sea temperature

The graph below shows the average sea temperature.

Seattle average sea temperature chart (Celsius) Seattle average sea temperature chart (Fahrenheit)
Average sea temperature around Seattle in degrees centigrade and fahrenheit
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 8.1 8 8.3 9.1 10.5 12 13.1 13.4 12.8 11.2 9.7 8.6
°F 46.5 46.4 47 48.4 50.9 53.6 55.5 56.2 55.1 52.1 49.5 47.5

Wind speed

The graph below shows the average wind speed.

Seattle average winspeed by month (km/h) Seattle average winspeed by month (mph)
Average wind speed in Seattle (mph and kmh)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
km/h 15 14 14 14 13 13 13 12 12 12 14 14
mph 9 9 9 9 8 8 8 7 7 7 9 9

A monthly average windspeed of over 16km/h or 10mph suggests a location is fairly windy.

Relative humidity

The graph below shows the average relative humidity.

Seattle relative humidity averages
Average relative humidity in Seattle
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
80% 77% 74% 71% 69% 67% 65% 68% 73% 79% 81% 81%
Seattle

Other monthly averages

UV index Best time to go?

Beta

Current (hourly) weather 15 day forecast

Seattle weather stats

Seattle weather statistics
Hottest month: August 23.5°C 74.3°F
Driest month: July 21mm 0.8ins
Sunniest month: July 10.8hrs
Coldest month: January 7.2°C 45°F
Wettest month: December 151mm 5.9ins
Warmest sea: August 13.4°C 56.1°F
Map showing location of Seattle (47.60621, -122.33207) Seattle map pin © Google

Locations nearby

Top United States locations