Avalanche forecast

Galena Summit & Eastern Mtns

Sawtooth Avalanche Center
View on map

Avalanche danger

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Out of date — this forecast expired 3 years ago.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

Highlights

Human-triggered avalanches large enough to bury people or destroy houses are very likely to occur. Large natural avalanches are possible. Slides can be triggered from flat terrain a long distance from where they release. Avalanches may impact roads, trails, and structures in the valley bottom. Stay off of and out from below steep slopes—slopes steeper than about 30 degrees.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    2–3

    You're very likely to trigger a large, unsurvivable avalanche. Some of these slides will be powerful enough to destroy a house.  A week of heavy snowfall is overloading weak layers near the base of the snowpack. These layers of facets and/or surface hoar on shadier aspects and crust + facet combinations on sunnier slopes are incredibly fragile and can be found on most slopes.Multiple Persistent Slab avalanches were triggered in the past several days. Yesterday, The Sun Valley Ski Patrol ski-triggered a large avalanche in closed terrain. The slide was 2-4 ft thick, 100 ft wide, and broke branches during its 900 ft vertical run (photo). These avalanches can release in surprising ways. You can trigger them from flat or low-angle terrain long distances away from steep slopes. Avoid avalanche terrain, including the base of slopes that are threatened from above. 

    This large remotely-triggered persistent slab avalanche on a NE slope at 9400' above the East Fork of the Big Wood broke 250 feet wide and ran over 1000' downslope.

  • Storm Slabs

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

    This zone picked up an additional 10-18" of snow in the last 24 hours. This rounds out a week of storms that brought anywhere from 2-4' of snow. Expect to find thick, touchy, slabs in areas that were affected by recent SE wind. These dunes, drifts, and pillows will be masked by ongoing snowfall and may be hard to identify.  While less likely, slab avalanches are also possible on steep slopes that are sheltered from the wind. Cracks shooting out from under your feet indicate you have found a sensitive slab.

    Loose snow avalanches are a real concern. These will be easy to trigger and may release naturally if the sun pops out this afternoon. Importantly, any of these smaller slides can trigger the much larger, much more dangerous Persistent Slab Avalanches described above.

Avalanche Discussion

An AVALANCHE WARNING is in effect, and the danger is HIGH. Natural avalanches may occur, and destructive human-triggered avalanches are very likely. Very large triggered avalanches over the past week clearly indicate that many slopes are teetering on the edge. Last night's burst of intense snowfall has just made things worse. 

Travel in avalanche terrain is not recommended. If you do head out, understand that even a low-angle ridge walk has consequences. Consider the very real possibility that a slide you trigger may affect an unsuspecting party below. Simply put, It's just plain dangerous out there.

Regions covered