Grand Coulee, WA has a semi-arid climate with hot summers and relatively mild winters. The average high temperature in July is 84 degrees Fahrenheit and the average low temperature in January is 25 degrees Fahrenheit. Precipitation levels are relatively low year round, with most of the area receiving around 10 inches of rain per year. Snowfall can occur in winter but usually occurs only at higher elevations. Grand Coulee, WA is located in the rain shadow of the Cascade Mountains which keeps it drier than areas to the west and south.
Grand Coulee, Washington gets 11 inches of rain, on average, per year. The US average is 38 inches of rain per year.
Grand Coulee averages 19 inches of snow per year. The US average is 28 inches of snow per year.
On average, there are 194 sunny days per year in Grand Coulee. The US average is 205 sunny days.
Grand Coulee gets some kind of precipitation, on average, 92 days per year. Precipitation is rain, snow, sleet, or hail that falls to the ground. In order for precipitation to be counted you have to get at least .01 inches on the ground to measure.
Weather Highlights
Summer High: the July high is around 87 degrees
Winter Low: the January low is 22
Rain: averages 11 inches of rain a year
Snow: averages 19 inches of snow a year