Lawinenlagebericht

Olympics

Northwest Avalanche Center
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Lawinengefahr

Mon
Hochgebirge
2 · Mässig
Waldgrenze
2 · Mässig
Unterhalb
2 · Mässig
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Kernpunkte

Unseasonably warm weather maintains the threat for glide avalanches. Two glide avalanches in the last 3 days serve as a reminder not to linger beneath slopes with large open cracks where the entire season's snowpack could fail unexpectedly. 

Lawinenprobleme

  • Glide Cracks

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Unlikely
    Größe
    1–2

    Water has been draining the snowpack at Hurricane Ridge for over a week  during an unusual January period with 12 days of mostly above-freezing weather. Warm temperatures enable the continue of the melt that lubricates the base of the snowpack. Recent avalanche activity tells us that the threat of glide avalanches continues. A D1.5 glide avalanche was reported 1/21 on a N aspect on the way toward Hurricane Ridge. A small D1 (SSE, 4600 ft) glide avalanche failed during the day on Thursday and covered half of the Hurricane Ridge road. On Sunday, large natural glide avalanches remain possible in isolated areas, primarily on slopes where large cracks have already formed. Small glide avalanches are possible in specific areas such as steep, unsupported slopes with underlying bedrock. Limiting your exposure to potential glide avalanche slopes is the best way to limit your danger.

    (1/13/2022)

    Glide crack on a road cut near Hurricane Ridge

     

    Photo: Sam Siemens-Luthy

Avalanche Discussion

Temperatures hit nearly fifty degrees on Saturday at Hurricane Ridge with temperatures remaining well above Friday night.  ONP rangers reported crusts on all aspects but slightly more softening on N aspects.

Near-record temperatures for multiple days in a row would typically have us very concerned. However, there are several factors that have prevented a more widespread avalanche cycle this time around: 1) Long winter nights and generally clear skies this time of year have contributed to the snowpack refreezing. 2) The low sun angle limits the duration of sunshine on any given surface. 3) Two wet avalanche cycles and 12 days of predominantly above freezing temperatures have transitioned the snowpack to be able to handle more unseasonable warmth.

Expect the snowpack to have sunken into the terrain significantly after consolidating 22 inches in the past 2 weeks. More unseasonable warmth is on the way Saturday night and Sunday, with temperatures remaining above freezing and highs once again approaching 50F.

Hurricane Ridge received 0.42" of rainfall Wednesday night through Thursday morning. Below the crusts, you will find plenty of rounded grains. On Thursday, observers noted a 2-inch crust on northerly aspects with the crusts breaking down during sunshine on southerly aspects. Wet loose avalanche activity had mostly subsided as the snowpack adjusted to sustained mild temperatures. We are not tracking any layers of concern at this time.

Adopt a spring mindset for travel in the Hurricane Ridge terrain:

  1. Challenging travel exists during the morning hours at all elevations and may continue throughout the day on many aspects. Make sure you can self-arrest before crossing a slope.
  2. Large cornices remain a hazard as warm temperatures continue to weaken them. Give them a wide birth on the ridges as you travel and don't linger on the slopes beneath them.
  3. As soon as the winds die down, crusts will begin to soften on aspects directly facing the sun. Pay attention for areas of "isothermal" snow developing first around rocks. Once this transition occurs, you can trigger small wet loose avalanches on steep SW-S-SE slopes once the crusts break down. These avalanches are primarily a concern near terrain traps where they could push you into rocks, trees, creek beds, or over a cliff.

2021-22 Forecast Schedule: Avalanche danger ratings will be issued for the Olympics every Friday through Sunday and during mid-week holidays. During the week when the Hurricane Ridge road is closed, forecast information will be updated daily to include expected conditions and relevant travel advice under the No Rating label.

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