Avalanche forecast

Olympics

Northwest Avalanche Center
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Avalanche danger

Mon
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

If you move into wind-stiffened snow, it will be easy to trigger an avalanche on Sunday. Likely locations for wind loading include areas near ridgelines, and above treeline terrain where textured snow surfaces or pillow-like drifts can help you identify and avoid the problem. Below treeline, avalanches triggered in stiffened snow may step down to a poorly bonded crust. Avalanche danger remains higher than forecast in the southern or eastern Olympics following 1-2 ft of snowfall since Friday.

Avalanche problems

  • Wind Slabs

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

    Winds picked up into the moderate range late Saturday, building shallow but reactive slabs. We're expecting moderate winds Saturday night, which will add to the problem. We don't have recent reports from exposed alpine terrain lending some uncertainty at these elevations. Consider avoiding large, open alpine terrain features where you are most likely to trigger a large avalanche unless you are confident that the snow remains loose and unconsolidated. Near treeline, slabs may be smaller and most likely to be triggered near ridgelines or within unsupported wind-stiffened snow. Shifting winds may form reactive slabs on either or both sides of a ridgeline. Visual clues such as rounded snow pillows may help you identify areas to avoid. Difficult trail breaking, settlement of the snow as you travel, and shooting cracks all serve as a reminder that you're entering the wind-affected or wind-loaded terrain where you'll want to keep your slope angle under 35 degrees.

    Below treeline, human-triggered avalanches 10-12" deep Friday and Saturday confirm that you can trigger an avalanche within a wind-affected or denser snow layer that can step down to the 2/24 crust. This crust (likely on W-S-E aspects) has a thin layer of facets on it, which means that the problem will not heal by Sunday. These slabs have ripped out just above poorly supported road cuts and we expect this potential to continue.

     

    (3/4/2023)

    Shallow slab avalanche stepping down to the the poorly bonded 2/24 crust down 12". 40 degree, E aspect, 4600 ft.

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    If the sun makes an appearance, all the recent dry snow will quickly destabilize in the strong March sunshine. These avalanches may initiate naturally off of shedding trees or rocks. If the snow becomes sticky or wet, navigate to colder shaded slopes not receiving direct sunshine. The first sign of rollerballs typically provides a short window of opportunity for you to move to safer terrain.

    Small dry loose avalanches were moving quickly in steep, wind-protected terrain Thursday-Saturday. This problem may become more limited to NW-N-NE aspects if the sun makes a serious appearance. Expect surface snow to destabilize and move with you in terrain approaching 40 degrees or steeper. These avalanches warrant greater caution above cliffs, depressions in the terrain, or rocks.

     

    Example: Rollerballs like this are often indicators that the snow surface is becoming weak and wet loose avalanches may soon follow.  

    Photo: Robert Hahn

Avalanche Discussion

IF YOU'RE TRAVELING IN THE SOUTHERN OR EASTERN OLYMPICS: Expect higher than forecast avalanche danger following 1-2 ft of new snow. In these areas a careful snowpack evaluation is necessary.

The snow settled 3" at Hurricane Ridge over the last 24 hours with only a skiff of new snowfall.  Hurricane Ridge, another 4" of low-density snow fell on Friday with light winds, adding to around 6" of snow fell on Thursday.  2 ft of right-side-up snow sits above the 1 cm 2/20 crust. In addition to the 2/24 crust-facet layer, we're monitoring a layer of slightly faceted snow just beneath the 2/20 crust. Although we don't believe the latter is a current cause for concern, it's always worth keeping an eye out for evidence to the contrary. If you hear whumphs or settlement, this layer may be problematic in your area. Snow coverage is currently excellent with forests now filled in above 4500 ft.

The photo gallery shows the snow structure responsible for a small human-triggered avalanche on Saturday in addition to a natural avalanche (from Thursday) and two human-triggered avalanches on Friday, all of which would be large enough to ruin your day in higher-consequence terrain. 

 

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