Bulletin d’avalanche

Salt River and Wyoming Ranges

Bridger-Teton Avalanche Center
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Danger d’avalanche

Tue
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
1 · Faible
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Périmé — ce bulletin a expiré 2 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Triggering an avalanche 1-3 feet deep at the middle and upper elevations today remains possible. Wind-affected areas hold the highest odds of triggering a large avalanche & can be identified by pillowed drifts or dunes, cornices along ridge crests, and stiffened snow surfaces. Consider moving to sheltered, low-angle terrain if you observe signs like cracking or collapsing, though these signs may not present before an avalanche releases, particularly as time passes. Avalanches are unlikely at low elevations except in isolated pockets of very steep terrain.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1–2

    New snow and consistent winds continue to form soft slabs 1-3 feet thick that may be sensitive to a person's or machine's weight today. It will be more likely to trigger these slabs in terrain over 35° in steepness and where the wind has deposited the new snow. Larger triggers, such as groups and snowmobiles, will also increase the odds of triggering. Multiple tracks can be on a slope before it releases.

    Slabs will have formed further down and across slopes than usual. Wind-affected areas can be identified by pillowed drifts or dunes, cornices along ridge crests, running down sub-ridges, and stiffened snow surfaces. Watch for signs of unstable snow, such as recent avalanches, shooting cracks, and whumping. 

     

    (2/7/2025)

    A D1 windslab NE, ~8500’ from two days ago in the Teton Zone. Note the drift formation and thicker crown in the center. 

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1.5–2.5

    Weak snow that formed during a dry period in the second half of January has been buried 3-5 feet deep by snowfall from the early February storms. These slabs sit on a variety of interfaces, including crusts on solar aspects and facets on shaded aspects. The likelihood of triggering slabs at this interface is decreasing over time. However, activating this layer may still be possible in very steep terrain. Large triggers such as a surface avalanche or multiple riders on a slope will increase the odds of impacting these layers in the middle of the snowpack.

    (2/3/2025)

    A large avalanche triggered from below near the Smith Fork.

    Photo: Ray Landry

Avalanche Discussion

Since the beginning of January, snowpacks across the state have nearly doubled. Recent snowfall has fallen on older, weak snow from January (~3-5 deep), in addition to a recent interface consisting of crusts/facets in the top portion of the snowpack (1-3 feet deep). This layer in the upper snowpack is the primary concern and remains reactive, trending stubborn to triggering. Though time will illustrate decreasing instability, the snowpack may not show us its cards while in this tapering process. This puts us, as backcountry users, in a particularly low-feedback scenario. Avalanches occur, get covered up by more snowfall, are blown in by the wind, happen overnight, go unreported, and are never seen. Understanding that we see a small spectrum of what happens in a mountain range on a given day or storm cycle is important. Even with so many user observations- helpful to the community and for which we are incredibly grateful- many have a bias toward frequented locations. They may be less representative of deeper or less visited areas. Keep this in mind when making travel plans today.  Snow will be less reactive over time, but uncertainty as to exactly which slopes in a range will stay just reactive enough for longer is unknown. Expect to find unstable snow in very steep, wind-loaded terrain.

If you see avalanche activity today, please consider submitting an observation HERE. Observations allow everyone to gain a better and more complete understanding of conditions. Thanks!

Régions couvertes