It has been a rollercoaster of unpredictable weather in the Pacific Northwest so far in water year 2022, yet as of early May, the snowpack remains above normal at 107 percent.
Aspect staff monitoring water levels along the Cedar River in western Washington.
In early May 2022, we’re officially more than halfway through the ‘Water Year’, which starts counting on October 1. This is also the time we typically reach maximum snowpack depth and begin the period of springtime run-off as warmer temperatures and longer hours of sunlight transport the snowpack stored in our mountains downstream into lower basins. If you’re outdoors right now in the PNW and looking near a river or stream, you’ll notice a robust color and churn in the water that only happens this time of year– that is born from the melting snow rushing down into lowland regions.
How is the PNW Water Year Looking in Spring 2022?
Relentless weather cycles have guided our snowpack through periods of below- and above-normal times, resulting in an exciting and volatile track of the 2022 SNOTEL data. Let’s take look back at how we ended up here.
An early trend of warm temperatures and atmospheric rivers in fall 2021 delivered an abundance of rain across Washington state. However, the warm temperatures and exceptional torrents of rain stunted the initial snowpack development state-wide, bringing worries of yet another below-normal snowpack. By early-December, the snowpack was at a dismal 40 percent of normal across the Pacific Northwest Region.
Figure 1. Snow Water Equivalent 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).
Then, cold temperatures accompanied by snow in mid- to late-December 2021 rocketed the snowpack on a trend well above normal. On January 8, 2022, the snowpack was nearly 140 percent of normal – a dramatic comeback from the previous month. Still, the uptrend was short lived and by mid-January and into February, the snowpack growth plateaued.
So Far, Is the Snowpack Feeding Our Water Needs?
Part 1 of this blog series ended with snowpack right near historical normal values. Since then and into spring, we’ve witnessed wild swings in weather resulting in uncertain snowpack conditions. We ended April with colder than average temperatures slowly reviving the snowpack and bringing it once again back above normal.
In Washington, most basins remain above normal, with the central Puget Sound basin leading the state with the highest snow water equivalent values, at 136 percent of normal to date. Only the Lower Yakima basin is below normal, at 90 percent.
Figure 2. Snow Water Equivalent in Washington . As of early May 2022, most basins are above normal.
Not all regions in the western US are faring well in the battle against below normal snowpacks. Zooming out, the northern states of Washington, Montana, Idaho, Oregon, and Wyoming all have snowpacks near or above normal while Nevada, Utah, and Colorado face below normal snowpack and challenging hydroclimate conditions ahead.
Figure 3. Snow Water Equivalent in Western US basins. Most basins to the north are above normal while basins in the south continue to struggle.
SNOTEL Forecast Secrets Unpacked
This two-part blog series that put a magnifying glass on 2022 Pacific Northwest snowpack shows how water supply from our largest and most valuable reservoir is constantly changing.
A useful key to forecast the security of our water supply and adapting to the everchanging conditions is the integrated network of nearly 300 SNOTEL climate monitoring stations scattered across the state.
Forecasting Washington’s water future is vitally important as communities, farmers, industries, and habitat all depend on this resource when the ‘reservoir’ stored in the snow transforms into streamflow that replenishes river and groundwater basins
