Boletín de aludes

Salt River and Wyoming Ranges

Bridger-Teton Avalanche Center
Ver en el mapa

Peligro de aludes

Sun
Alta montaña
2 · Moderado
Límite del bosque
2 · Moderado
Bajo el límite
1 · Débil
Desactualizado: este boletín caducó 2 years ago. Estás viendo condiciones pasadas, no el boletín vigente.

Lo esencial

Triggering a large avalanche failing on weak layers buried 1-3 feet deep is unlikely but carries high consequences. These avalanches are most likely on very steep, rocky, wind-affected terrain. Continue to evaluate the snowpack and use safe travel practices in avalanche terrain.

Problemas de aludes

  • Persistent Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Unlikely
    Tamaño
    1.5–2.5

    Although triggering an avalanche involving buried weak snow layers has become unlikely, it can still occur, especially above 8000 feet in terrain connected to very steep (>35°) slopes. This problem type can appear inactive - the last reported avalanche in this zone occurred 9 days ago on January 9th in Cliff Creek - but should remain a concern to backcountry users due to its difficult-to-predict nature. You're most likely to trigger a large hard slab avalanche 1-3 feet deep on the north half of the compass - where snowpack depth is variable. These avalanches are easiest to trigger in spots where the snowpack is thin. Signs of a thin snowpack include wind-scoured snow near ridges, cliff bands, and rocks sticking out of the snow. Signs of instability, such as collapsing and cracking, might not be present before triggering a persistent slab avalanche. 

    Larger triggers, such as groups, snowmobiles, or falling cornices, will increase the odds of impacting these weak layers. This avalanche problem is currently a low-likelihood but high-consequence scenario. Snowpack evaluation and safe travel practices remain the best methods for avoiding triggering an avalanche involving the old snow layers.

    (1/13/2025)

    This photo shows an example of where you can trigger persistent weak layers. 

Avalanche Discussion

The Salt and Wyoming Ranges received up to 5" of new snow with light winds from the NW. It’s unlikely these conditions have created a fresh avalanche problem, but exceptions may be found. Stay alert for isolated pockets of wind-drifted snow that may have developed at high-elevation ridgelines. Keep an eye out for signs of instability such as cracking, and the formation of small drifts. These avalanches will most likely be small but could carry high consequences in complex terrain. Move to terrain sheltered from the wind if you notice signs of instability. 

The spatial distribution of overall snow depth varies across this forecast zone. Areas of the Salt River Range contain around 20” of more snow than areas of the Wyoming Range. This is important to acknowledge as areas with a shallower snowpack generally have a weaker snowpack. A shallower snowpack also means that the overlying slab above the persistent weak layers is thinner and easier to trigger. Therefore, if you’re traveling around the Wyoming Range or any area with a shallower snowpack, you should use more conservative terrain choices. While the likelihood of triggering an avalanche has decreased, persistent slab avalanches are difficult to predict. Obvious signs of instability such as recent avalanches, collapsing, or shooting cracks may not be present before triggering an avalanche. We have been seeing positive trends of increased stability in the buried weak layers during our travels last week. We are not out of the weeds woods quite yet though. Be patient, there will be plenty of days later in the season where stepping out into more complex terrain will be safer with less severe consequences.

Salt River Range:  Total Snow Depth- 68" (Commissary Ridge 9,330')

Wyoming Range: Total Snow Depth- 44" ( Blind Bull 9,000')

Regiones cubiertas