How much Washington’s snow accumulates during the annual snow season has implications throughout the year. The snowpack is considered a crucial climate-related variable in the Pacific Northwest that affects water supplies to agriculture, to fish, to hydropower production and recreation.

Washington’s rivers, lakes and reservoirs rely on the mountain snow to supply water through the summer months. The state’s agriculture and outdoor recreation industries also depend on the snowpack for irrigation and water to support salmon and other fish habitats. The annual snow season typically lasts from October to May each year.

We’re tracking this season’s snowpack through maps and charts to better understand our water supply in 2022.

CURRENT SNOW SEASON

This snow season started in November below the 1991-2020 median for most of the Washington. The Olympic and Northern Cascade ranges were slightly above normal. However, warmer than normal temperatures and above average rainfall at the start of December, have dropped almost all of Washington’s basins to far below normal, especially in the southern and central Cascade range and in the eastern basins of Spokane and Walla Walla.

Last November saw most of Washington’s basins well over the 1981-2010 median. December 2020 saw a slight decrease across most all of Washington, except in the eastern basins where warmer temperatures kept the snowpack at or below the 90% to 109% levels into the month of January. Colder temperatures brought more snow in mid-February to mid-April, increasing and holding last season’s snowpack well above the 30-year norm (1981-2010) for most of Washington. Warmer temperatures in late April caused the snowpack in some basins east of the Cascade Mountains to melt early. The first week of May saw the Lower Yakima Basin under 60% for the 30-year norm. The Spokane and Lower Snake both dropped to 70% of norm for the month of May.

DECEMBER SNOWPACK

Comparing 2021’s snowpack to the past season’s for select basins on the first reading of the day. The annual snow season lasts from October to May.


NOVEMBER SNOWPACK

Comparing 2021’s snowpack to the past season’s for select basins on the first reading of the day. The annual snow season lasts from October to May.


FIRST SNOWFALLS AT SNOQUALMIE AND STEVENS PASSES

Historically, Stevens Pass gets its first snow before Snoqualmie Pass does. This year at Stevens Pass, 1 inch of snow arrived on Nov. 2. Last year, Stevens Pass had 2 inches on Oct. 11. This year at Snoqualmie Pass, there were 2 inches of snow on Nov. 6. Last year, Snoqualmie Pass had 1 inch on Oct. 24.