Avalanche forecast

East Slopes Central

Northwest Avalanche Center
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Avalanche danger

Wed
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

Winds have blown from multiple directions over the past few days, so don't be surprised if you find wind-drifted snow in unusual areas. Any triggered avalanche in wind-drifted snow has the potential to grow much larger and could be unsurvivable. So, seek out more sheltered slopes that are less than 30 degrees. 

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–3

    You can trigger avalanches that fail on weak layers that exist 2-4 ft below the snow surface. It's been several days since the last known persistent slab avalanche in the east-central, but observers as of Sunday reported multiple whumping collapses in the Blewett Pass area. Unfortunately, this structure is widespread throughout the zone and in many parts of the region. Additionally, a  layer of buried surface hoar from January 2nd sits an inch or two above a crust from December 30th and has been the culprit of several avalanches in the southern part of the zone. Persistent slabs take persistent patience. So, your best mitigation tool will be to stay off open steep slopes to reduce the odds of you triggering one. 

    (1/10/2024)

    Backcountry travelers near Lake Wenatchee remotely triggered this avalanche from a low angle adjacent slope. This avalanche ran on weak, facted snow over the Solstice Crust.

    Photo: Pat Riffie

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    Winds have blown from multiple directions (including from the east) in the past days, so don't let your guard down as you change aspects. As you travel, use visual clues to help you identify where the problem exists. Look for textured surfaces, pillow-like slabs, or sharp drifts to help you spot where wind slabs could lurk. As always, pump the brakes and default to less exposed terrain if you notice shooting cracks or hollow-sounding snow under your feet or sled. 

    Any triggered wind slab could step down to more deeply buried weak layers, become very large, and propagate across terrain features. So increase your margins from these pockets if you are in wind-exposed terrain. 

    (12/1/2023)

    Shooting cracks are an obvious sign of instability that should not be ignored.

    Photo: Joe Dellaporta

Avalanche Discussion

Backcountry travelers continue to report notable signs of instability, such as whumphing collapses and propagating test results. It's been a quiet few days, avalanche-wise, but that may change soon as a weather system rolls into the region on Wednesday. To make the situation more complicated, observers across the region have also reported pockets of surface hoar and near-surface facet growth from the recent cold, dry spell. So if you're out Tuesday, be sure to track surfaces and be ready to dial it back as snow starts tricking in. 

Over 3ft of snow has fallen in most areas of East Central this week, with around 1.5ft in the easternmost portion of the zone. NWAC forecasters went to the lower slopes of Cashmere on Saturday and found small faceted grains over a crust above 3,000ft. This is the classic weak structure that can result in a persistent slab avalanche. Another NWAC forecaster visited the Salmon La Sac area on Wednesday. At 4600ft, she found around 70cm of new snow with a thin melt-freeze crust from a brief warmup midstorm buried 45cm down. This new melt-freeze crust showed potential for propagation in a snowpack test. Weak snow beneath the Solstice Crust also showed propagation in these test results. 

If you get out, let us know what you see by submitting a public observation!

 

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