Nearly 300 climate monitoring stations (SNOTEL sites) scattered across Washington state hold the data to our largest and most valuable reservoir: The Winter Snowpack. As of early February 2022, our water year began typically but has trended warm. We did get plenty of snow in the Cascades and Olympics – the critical mountain ranges that store our state’s water future. Read on for Part 1 of our two-part series, where we’ll distill the SNOTEL data, and then come back in the spring to see how the 2022 snowpack fed water resources in the Pacific Northwest.
A look at Mount Shuksan during some backcountry ski touring. This area around Mount Baker receives some of the highest snowfall in the Pacific Northwest. In the spring, the melting snowpack feeds major rivers in Northwest Washington, across Whatcom and Skagit County.
Snowpack is the Key to Fish, Flows, and Agriculture
Snowpack is vital to Washington’s water supply; we all depend on this resource as it piles in our mountains in the winter and melts in the spring to replenish streams and groundwater. Its impact is counted on by:
Farmers – To grow crops with irrigation water from streams fed by snowpack
Cities and Counties – To supply homes from groundwater replenished by snowpack
Industries – To generate hydroelectric power from rivers fed by snowpack
Salmon – To feed cool and clear water to critical fish habitat
Winters of below-normal snowpack add strain to the teetering balance of water supply and demand and challenge water managers throughout the state. Fortunately, this strain does not come as a blindside because of the SNOTEL network.
Basin-filled map showing percent of median across Washington State on February 1, 2022.
SNOTEL Surveys Washington’s Water Future
A growing network of nearly 300 climate stations (SNOTEL sites, short for SNOwpack TELemetry) monitor our changing snowpack reservoir in real-time, revealing whether the snowpack is below- or above-normal. This is managed by the U.S. Department of Agriculture, who provide this free publically available data. This allows regulatory agencies to make early decisions to manage the level of risk in receiving more or less water than planned for in spring, when the ‘reservoir’ stored in the snow transforms into streamflow that replenishes rivers and groundwater basins throughout the state.
Snow Water Equivalent – Not Just for Skiers and Boarders
Many people may associate snowpack in terms of snow depth. However, in the context of water supply to fish/flows/communities, of greater importance is the snow water equivalent (SWE). If you take a volume of snow and melt it, the volume of water left is SWE. SWE is a better measure of how much water is available in the spring meltout. The water content of falling snow can be highly variable: five feet of dry powdery snow is not equivalent to five feet of wet heavy snow.
How’s it looking? A Summary of Washington February 2022 Snowpack
Water year 2022 (‘Water Year’ always starts on October 1 annually, unlike the calendar year) began typical and uneventful; however, by mid-November, a battering of atmospheric rivers delivered warm and wet conditions to the state. While rainfall records were shattered (wettest fall in recorded Seattle history), warm temperatures quickly erased any progress of previous snowpack development and the 2022 snowpack (the black line) initially fell under the normal line (see green line below). As we crossed into December, the snowpack regained momentum, crossing above the normal line. By January and into February, the state’s snowpack plateaued, ending right at the normal values, to date.
Snow Water Equivalent (SWE) in Pacific Northwest Region. The black line shows 2022 SWE trends to date. The green line shows normal “median” snowpack blue and red lines show the max and min (% median).
As of early February 2022, the Pacific Northwest snowpack is 102 percent of normal. In Washington, the highest reading of SNOTEL data in the State were at 109 percent of normal in the Lower Columbia Basin. The Lower Yakima has the lowest reading at 83 percent of normal.
Using SNOTEL to See Our Water Reservoir Forecast
As the SNOTEL data illuminates, our snowpack story is fluid. This year, so far, is trending around normal. However, the value of having 300 monitoring stations is mountains of data to measure our state’s water health. This gets more and more important as the weather turns warmer and farmers, fish, and communities seek out the meltout from the reservoirs in the mountains. Check back in April 2022 for Part 2 of our SNOTEL water summary where we’ll look back at how our 2022 snowpack reservoir turned out.