Bollettino valanghe

Mt Hood

Northwest Avalanche Center
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Pericolo valanghe

Wed
Alta quota
2 · Moderato
Limite del bosco
1 · Debole
Sotto il limite
1 · Debole
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In sintesi

You can trigger an avalanche on slopes steeper than 35 degrees where you find wind-drifted snow or wet slushy slow 6" or deeper. Upper elevations may remain cold enough for wind slab formation. A potential changeover to rain at these elevations also makes wet loose avalanches possible.

Problemi valanghivi

  • Wind Slabs

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

    As snow levels rise, winds may thicken existing slabs or create new ones that you can trigger above treeline. These slabs sit on a firm crust formed January 6th. Wind slabs could be reactive to human traffic on unsupported slopes greater than 35 degrees. Cornices have grown significantly in the past week and may act as triggers for wind slabs on the slopes below. Navigate away from areas of active snow deposition or below sharp, fresh cornices. Assess small test slopes before committing to larger terrain features at upper elevations. Cracking of the snow under your feet or evidence for recent avalanche debris should guide you toward supported slopes sheltered from the wind. 

    In the alpine, at least one very large natural avalanche occurred during the recent storms. Although similar avalanches are unlikley, this outlier event should give you pause if you venture high on Mt Hood. 

    Example: Wind slab triggered on lee slope of ridgeline.

    Photo: Andrew Kiefer

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    You're most likely to encounter wet avalanches large enough to harm you in areas changing to rain for the first time. Snow levels rose to 6000 ft by Monday afternoon on Mt. Hood. As warming reaches higher elevations, expect wet loose avalanches in less wind-affected areas that are more likely to take you for an unwanted ride above treeline. Seek out slopes with low consequence away from terrain traps where you find wet, unconsolidated snow surfaces.

    (1/7/2022)

    Small natural wet loose avalanche (D1) along Hwy 35 (NE aspect, 3100ft)

    Photo: Andrew Kiefer

Avalanche Discussion

Several inches of snowfall on Monday changed to rain up to around 6000 ft, producing small avalanches mostly confined to the new snow.  Expect cloudy, windy, and very mild weather to continue Tuesday and Wednesday with periods of light precipitation.

A major loading event January 2-7 brought 5-7+ feet of snow and caused a widespread natural avalanche cycle, but had a chance to settle and stabilize over the weekend.  Mt Hood Meadows Ski Patrol triggered a handful of wind slabs 6-12in deep with explosives Saturday and Sunday. Reports over the weekend indicated few signs of unstable snow. 

The most notable avalanche from the cycle last week was a very large natural on the upper Newton Clark Glacier. The crown was easily 10ft deep in places and debris reported ran 4500ft down into Newton Canyon. A public observation highlights this avalanche, in addition to another notable avalanche near treeline. Many smaller avalanches ran during the storm in wind drifted snow as well, along with reports of natural cornice falls. Wet avalanche activity was also widespread below the treeline. Surfaces on Tuesday will depend on your elevation with rain rills at lower elevations, increasingly moist and dense snow above a crust at mid-elevations, and scoured icy surfaces or deep wind drifts in the alpine.

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