Avalanche forecast

Galena Summit & Eastern Mtns

Sawtooth Avalanche Center
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Avalanche danger

Thu
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
2 · Moderate
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Out of date — this forecast expired 2 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

To reduce the chance of triggering large avalanches, avoid steep slopes where the wind has formed drifts or stiffened the snow surface. Wind features— and any avalanches you trigger— will become larger as you gain elevation. In sheltered terrain, triggering large avalanches on deeply buried weak layers is less likely but not out of the question. 

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1.5–3

    Triggering 2-4 foot thick avalanches remains possible, especially in recently wind-loaded terrain. The snowpack has not fully adjusted to the weight of the February storms, and recent wind loading has kept some slopes teetering on the edge. Avalanche activity has been focused on the northern 2/3 of the compass (W-NW-N-NE-E-SE) in middle and upper elevation terrain, failing on faceted snow (commonly associated with crusts) buried about 2-4 feet deep. On SW and S aspects, we've observed less Persistent Slab activity but can't yet rule them out.

    These avalanches can release in surprising ways. You can trigger them from flat or low-angle terrain long distances away from steep slopes, and they can break far above you. Several riders or skiers could safely ride a slope before someone triggers a slide. You may or may not experience snowpack collapsing or other obvious signs of instability before triggering an avalanche.

    Unfortunately, snowpack stability tests will not conclusively determine if a given slope will or will not produce a Persistent Slab avalanche. If your primary goal is to not get caught in an avalanche, staying off of and out from below steep slopes is the most reliable way to reduce your risk.

    Observations indicate these avalanches are most likely as you move to the southern, eastern, and northern portions of this zone, away from Galena Summit. 

  • Wind Slabs

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

    You could trigger soft or hard wind slabs up to 2 feet thick in exposed terrain. Days of loading wind speeds formed slabs, drifts, and cornices near  ridgelines and on the sides of crossloaded gullies. Today's wind may continue building slabs and wind features. In the alpine areas of the White Cloud, Boulder, and Pioneer Mtns, watch for stiff pillows of snow below large cliff faces, chutes, and couloirs.

    The fresh slabs rest above persistent weak layers (crusts, crusts + facets, facets, and possibly surface hoar) on many slopes. How could they behave?

    • Natural cornice fall could trigger wind slabs
    • You could trigger slabs remotely (from above, below, or to the side) - see photo
    • Hard slabs (slabs stiff enough to support the weight of you or your sled) are notorious for breaking above people
    • The slabs could be very sensitive to your weight, even where they are quite soft 
    • Avalanches may be wider than you expect

    Cornices, drifts, dunes, rippled snow surfaces, and chalky snow pillows are visible clues that the wind has been at work. Give large or overhanging cornices a wide berth. If you see cracks shooting out in front of your skis or boards, you've probably found a wind slab. If you feel the snow stiffen beneath your sled or skis, its time to steer clear of large or consequential avalanche paths. 

    (2/27/2024) This slab avalanche was triggered Tuesday from 50 ft away on a low-angle ridgeline. It broke widely in wind-drifted snow on a thin layer of facets above a crust. Cracks extended another 100' cross-slope beyond the crown. Smiley Ck, ENE @ 9,100'.

    Photo: Sawtooth Avalanche Center

Avalanche Discussion

Conditions and stability vary significanlty in this zone.

Alpine areas (White Clouds, Boulders, Pios, Smoky crest): Expect to find freshly wind-loaded slopes, and most of these areas will have well-developed facets and/or crusts beneath the slabs. Large Persistent Slab avalanches are definitely on the table in these places in this zone. Don't trust slopes with stiff new snow on the surface that is not crusty or icy.

Near Galena Summit and the Smoky Crest: This area has a deeper snowpack than the majority of this zone. To reduce your risk, avoid wind-loaded areas and recognize there's an outside chance of triggering large slides on deeply buried weak layers at middle and upper elevations. 

South of Galena Summit: This terrain generally has a thinner snowpack and a greater chance of triggering Persistent Slab avalanches on layers near the bottom of the snowpack. Be careful near all recently wind-loaded slopes. 

Regions covered