Boletín de aludes

Presidential Range

Mount Washington Avalanche Center
Ver en el mapa

Peligro de aludes

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

Lo esencial

You could trigger a large avalanche in wind-drifted snow in steep easterly terrain above 3000 feet. Larger, more destructive avalanches are possible to trigger on east-facing and south-facing slopes above 3000 feet if you find a thin spot in the snowpack. Carefully planned route finding, terrain management, and snowpack assessment are critical for safe travel in avalanche terrain today.

Problemas de aludes

  • Wind Slabs

    • Alta montaña
    • Límite del bosque
    • Bajo el límite del bosque
    Probabilidad
    Possible
    Tamaño
    1–2

    What and where is it:Wind slabs 5 - 15 inches thick that formed from yesterday’s snow and wind can be found primarily on easterly aspects and where the terrain has created protection from the wind. These slabs may be sensitive to the weight of a person.

    How can you recognize it: Look for rounded, smooth pillowy areas of new snow. Cracking under your feet, or softer snow that is deeper than the top of your boot are warning signs of the avalanche problem. Deeper drifts represent a bigger avalanche problem. Features that may be harboring a more sensitive wind slab could be underneath ridgelines, cliffs, convex features, or in narrow gullies.

    How can you manage it:Identify wind-loaded areas and assess your exposure based on the consequences of a slide. Using a ski pole, probe, or your boot penetration will help you to assess the size. To limit your exposure to avalanche hazards, avoid the thicker wind slabs. Pay attention to slope angle as you travel, your chance of triggering a slide in a new wind slab increases as the slope angle increases above 30 degrees.

  • Persistent Slabs

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

    What and where is it:Old, hard slabs are sitting on a buried persistent weak layer showing potential for instability above an ice crust bed surface. Forecasters have identified this structure as having the potential to slide on east and south aspects above 3000 feet, specifically in the Summit Snowfields, Summer Lion Head Trail, and gully entrances on the south face of Tuckerman Ravine. These slabs are up to 1 meter deep and could produce a dangerously large avalanche with serious consequences. Note that this avalanche problem exists just to the north of where the Lion Head Trail leads to Split Rock on the summit cone.

    How can you recognize it: Identifying this avalanche problem is difficult without digging a deep pit, as there will be no visible clues. "Whumping" sounds as a warning are unlikely, and the slopes will likely appear unreactive.

    How can you manage it:Understanding where there are likely trigger points for this avalanche can be challenging or impossible. Careful and strategic route finding, terrain management, and minimizing exposure time are critical if you choose to travel in avalanche terrain.

Avalanche Discussion

Multiple observations from yesterday (Obs 1, Obs 2) showed the newly formed wind slab to be reactive to a person’s weight. As wind-loading continued through the afternoon and evening yesterday, wind slabs today have the potential to be larger, and more connected across east and south-facing avalanche terrain than they were yesterday. Actively take steps to identify areas of concern and use travel techniques that minimize your hazard exposure. 

The MWAC team has been identifying locations of a persistent weak layer on east-facing and south-facing terrain that has developed enough to be a concerning avalanche problem moving into the foreseeable future. Triggering this layer is unlikely, however, finding a thin spot in the slab, where your energy can more effectively affect the buried weak layer, could trigger a dangerous, large, hard slab avalanche. Without digging down into the snowpack, it won’t be possible to assess the reactivity and potential size of this avalanche problem. This is a risk that should be actively debated within your group before entering avalanche terrain. If you do decide to travel in avalanche terrain, take steps to minimize your exposure with strategic travel techniques and terrain management.

OBSERVATIONS: Please consider submitting an observation on our website or in the new Avy phone app of what you are seeing in your travels. Submitting an observation hones your skills, informs other users, and improves our forecasts.

Regiones cubiertas