Bollettino valanghe

Olympics

Northwest Avalanche Center
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3 · Marcato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
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In sintesi

Warming temperatures may cause cornices to fail naturally and trigger large and potentially deadly avalanches on the slopes below.  Be mindful of other parties while traveling along or beneath ridgelines and avoid lingering below slopes with large overhanging cornices.  Wet snow avalanches are possible on steep sunny slopes as the day warms. 

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    2

    Natural cornice fall triggered at least two large wind slab avalanches between Friday afternoon and Saturday afternoon in the Hurricane Ridge area.   Avoid steep open slopes directly below ridgelines where you find firmer wind drifted snow and avoid lingering below slopes with large overhanging cornices.  Whether triggered naturally or by backcountry travelers, these slab avalanches can break down to recent storm layers and become large enough to bury, injure or kill you.  You can stick to lower angle slopes not capable of producing large avalanches.  You are most likely to trigger a wind slab avalanche on northerly aspects near and above treeline. 

    Large cornices have formed along ridgelines following several days of stormy weather.  Be mindful of parties below you if traveling along ridgelines.  Make sure to give cornices a wide berth as they often break back further than you expect.  With high freezing levels in the forecast, cornices may fail naturally again on Sunday.   

    (1/8/2022)

    Crown (red line) of a large avalanche on North Bowl in Hurricane Ridge area that released sometime Friday afternoon - Saturday (1/8). The avalanche was likely triggered by natural cornice fall.  Estimated by NPS: HS-NC-R3/D2.5, northerly asp 5300'.   

    Photo: ONP Rangers

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    We have high confidence the weather will be mild and become sunny on Sunday but we don't know how widespread or how big loose wet avalanches may become, especially since some areas have already seen loose wet avalanches.  Avalanches can run faster and become larger on steep slopes where recent snow overlies a firm crust. If you see pinwheels, natural loose (point releases or sluffs) wet avalanches or find yourself sinking into the snow surface deeper than your ankle, it's time to seek out lower angle terrain or a different aspect.  Don't let a smaller slide catch you off-guard and slam you into trees or other terrain traps. 

    (1/6/2022)

    Some wet loose activity already ran this week with the warm-up.  Large (D2) Wet Loose avalanche with some slab-like characteristics. Tunnels slide Path. Path terminus at Hurricane Ridge Road around 3000 ft.

    Photo: ONP Rangers

Avalanche Discussion

Hurricane Ridge picked up nearly 3 feet of snow over the last week but was spared relative to the snow-pocalypse that the Cascades experienced Wed night - Friday.  It's worth noting the southern portion of the Olympics received far more precipitation and likely saw a different peak in avalanche conditions.  On Saturday, NPS rangers and observers noted that S-SW aspects along ridgelines were largely stripped of snow and had a semi-breakable crust.  On northerly aspects and away from wind effect, the storm snow was largely right side up.  This storm cycle had produced few slab avalanches until the last 24 hrs when large cornice fall triggered two large slab avalanches on the slopes below.   On Friday, NPS staff noted a handful of wet loose (size small to large) avalanches in south and east-facing gullies that ran during the course of the storm cycle including Goat Creek.

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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