Lawinenlagebericht

Olympics

Northwest Avalanche Center
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Lawinengefahr

Sun
Hochgebirge
4 · Gross
Waldgrenze
3 · Erheblich
Unterhalb
3 · Erheblich
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Kernpunkte

Dangerous avalanche conditions will develop in most areas Friday night and Saturday as a strong storm rocks the Olympics.  Expect wet snow avalanches at lower elevations where snow transitions to rain.  Backcountry travel is not recommended at upper elevations where heavy snow and wind will increase the likelihood of larger avalanches. 

Lawinenprobleme

  • Storm Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Very Likely
    Größe
    1–2

    Strong to extreme winds, heavy snow and a warming trend through mid-day Saturday are a recipe for unstable snow.   Storm slabs that are small near treeline may become large in wind-drifted areas. The winds should be strong enough to distribute new snow further downslope and below ridgelines than usual.  This will be a difficult day for route finding anywhere near ridgelines.  Avoid lingering in the runouts below large avalanche paths where natural slides could run from above. 

    A red flag observation like natural slab avalanches (like this small one above the Hurricane Ridge road cut) will tell you instability is on the rise.  (12/30/2020) 

  • Loose Wet

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Very Likely
    Größe
    1–1.5

    Rising snow levels will push rain into the 4000-5000' range Saturday morning.  Any new snow that falls overnight will be primed to come down as a wet loose avalanche.  Most wet loose avalanches should be small, but in isolated areas, wet loose avalanches could gouge down to older snow that fell earlier in the week.  If you start to sink into wet snow deeper than your ankles or see natural wet loose avalanches occur,  take nature's cue and move to lower angle terrain.  The same elevations where you're most likely to see wet loose avalanches are the same places where snow cover is thinnest; think about what happens if you get knocked off your feet near a terrain trap.  

    Small wet loose avalanches like the ones in this photo can grow larger in areas where temperatures warm and there's more cold snow to entrain. Photo: Sam Luthy 12/31/20. 

Avalanche Discussion

During the workweek moderate winds sculpted the snowscape in the Hurricane Ridge area.  On Thursday, NWAC Observer Sam Luthy and NPS staff found wind rolls,  new cornices, and stripped windward surfaces all along ridgelines.   Directly below lee ridgelines, 6-8" of denser wind-affected snow could be found.  No new avalanches were observed in the Maggie's area. 

Heading into this weekend's storm and outside of wind affected areas, the snowpack is generally right side up and about 3' (1m) deep above 4500' in sheltered areas.  The landscape has filled in nicely at mid and upper elevations, but we aren't close to mid-winter depths. Keep an eye out for sharks lurking not too far below the snow surface at lower elevations (rocks, logs, etc).  Observers are tracking a weak snow (facet) crust combination about 3' down on northerly aspects near treeline in the Hurricane Ridge area.  No known avalanches have been reported on this layer, but it's worth keeping an eye on while we head into a stormy weekend.  At the bottom of the snowpack, you can find a thick crust from late November. 

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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