Avalanche forecast

East Slopes North

Northwest Avalanche Center
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Avalanche danger

Sat
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low
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Out of date — this forecast expired 3 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Expect that you can encounter slab avalanches on leeward sides of ridges near and above treeline. Avalanches will be larger and easier to trigger at the highest elevations. You may see some wet rollerballs or small avalanches below treeline, but they shouldn't be significant enough to be dangerous

Avalanche problems

  • Wind Slabs

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

    Watch for fresh avalanches, blowing snow, and cracking to indicate which slopes will be prone to avalanches. Steer around pillows, and convexities on leeward slopes below ridges and at the base of cliffs. Both southeasterly and southwesterly winds will be strong enough to drift new slabs at upper elevations. Expect that around 6" of new snow could drift into 1-foot-deep slabs. Slabs will build overnight and may continue forming throughout the day. You may be able to trigger avalanches more easily on northerly aspects and at upper elevations. Cooler temperatures and shade may have formed a weak layer over a slick crust at the new/old snow interface. Use quick tests and dig just below the surface to look for this weak layer.

    (4/4/2023)

    Crown on NNE Aspect of Silver Star Mountain. This avalanche likely occurred due to wind loading. 

    Photo: Willie Webster

Avalanche Discussion

Information is very limited in the zone and our confidence in the forecast is low. As of Thursday evening, the storm has brought only a dusting of snow and temperatures are staying colder than expected. There may be a chance for wet avalanches. This could be an issue on low elevation, northerly aspects well-west of Washinton Pass, as well as on steep sunny slopes as clouds break Saturday afternoon.

Up 4-8" of snow accumulated from March 31st to April 3rd. Prior to the current storm, northerly aspects and upper elevations may have harbored weak snow surfaces and which may form a poor bond at the new/old snow interface. While we're now well into April, the avalanche conditions and snowpack are closer to that which we typically see in mid to late winter. Much of the snowpack is nowhere near transitioning to typical spring melt-freeze conditions.

As access has become difficult in many areas, we have minimal precise information from the zone. On Tuesday, Willie Webster went on an aerial tour of the zone and produced some great images of the current snow cover and recent avalanche activity. Notable were a couple of older avalanches including a very large natural slab avalanche on a NNE aspect of Silverstar Mtn and a natural glide avalanche on Hinkhouse Peak. See the photos below. On March 30th, Willie reported large debris piles on Harts Pass. The road was melting out quickly near Deadhorse Pt. He found a mix of sun crusts on the surface, though higher elevations looked to hold a cold, layered snowpack. 

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