Sammamish (WA) monthly weather averages

Average daytime temperature

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

Sammamish average temperature chart (Celsius) Sammamish average temperature chart (Fahrenheit)
Average monthly temperatures in Sammamish (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 6.7 9.5 11.1 13.6 17.2 20.3 23.1 23.1 20 15.1 9.9 7.1
°F 44.1 49 52 56.5 62.9 68.5 73.6 73.5 68.1 59.2 49.8 44.7

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.

Sammamish monthly rainfall chart (mm) Sammamish monthly rainfall chart (inches)
Average monthly rainfall in Sammamish (mm and inches)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
mm 180 128 123 92 68 59 30 41 66 108 177 186
inches 7.1 5.1 4.8 3.6 2.7 2.3 1.2 1.6 2.6 4.3 7 7.3
Rainy days 17 15 16 13 10 8 5 6 9 12 17 18

Average annual rainfall in Sammamish: 1182.5mm (465.6 inches)

Average daily sunshine

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

Sammamish average daily sunshine chart
Average daily sunshine Sammamish
  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 5.1 2.7 2

Day / night temperatures

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

Sammamish average minimum / maximum temperatures (Celsius) Sammamish average minimum / maximum temperatures (Fahrenheit)
Maximum and minimum daily temperatures in Sammamish (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Min °C 1 2.2 2.7 4.4 7 10.1 11.8 11.9 9.7 6.5 3.6 1.6
Max °C 6.9 9.7 11.3 13.9 17.4 20.6 23.4 23.4 20.3 15.4 10.1 7.2
Min °F 33.7 35.9 36.9 39.8 44.6 50.1 53.2 53.3 49.5 43.6 38.4 34.9
Max °F 39 42.6 44.6 48.4 54 59.5 63.7 63.7 59 51.6 44.2 39.9

Sea temperature

The graph below shows the average sea temperature.

Sammamish average sea temperature chart (Celsius) Sammamish average sea temperature chart (Fahrenheit)
Average sea temperature around Sammamish 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.

Sammamish average winspeed by month (km/h) Sammamish average winspeed by month (mph)
Average wind speed in Sammamish (mph and kmh)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
km/h 14 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.

Sammamish relative humidity averages
Average relative humidity in Sammamish
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
79% 76% 73% 69% 67% 66% 64% 67% 72% 78% 80% 81%