Bollettino valanghe

Togwotee Pass

Bridger-Teton Avalanche Center
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Pericolo valanghe

Thu
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
Senza grado
Non aggiornato — questo bollettino è scaduto 3 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

New snow overnight added more weight to a weak snowpack. You could trigger an avalanche today especially in exposed location containing older wind slabs.  Safer conditions can be found on wind-sheltered, lower angled slopes.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    Look for and avoid areas of drifted snow on steep slopes. Wind was light during the past 24 hours so signs of older drifts may be hard to see. These areas are the most likely to be triggered  and may crack a long distance given the weak layer of snow beneath the surface almost eveywhere in this zone. Wind-affected areas can be identified by pillowed drifts, cornices along ridge crests, running down sub-ridges, and/or stiffened snow surfaces. 

    (2/13/2024)

    Togwotee Pass, northwest shoulder Radio Tower, 10,400', northwest aspect. Natural D2 in wind affected terrain, down to December weak snow.

    Photo: Travis Baldwin

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    A new round of weak snow was buried on February 2nd. These weak layers are most consistent on the east, north, and west-facing slopes and have slightly less potential on southerly aspects. This interface is now buried 1-3 feet on average. In the last week, human-triggered avalanches have been reported on this layer. This avalanche problem can be remotely triggered from flat terrain or propagate widely across terrain features.  Shooting cracks or collapses are a clear sign of danger, but these obvious signs of instability will not always show themselves before an avalanche releases.

    (2/11/2024)

    Large recent natural avalanche on Togwotee Pass.

Avalanche Discussion

A snowmobiler was buried and killed in the Sierra Madre Range last Friday when his party triggered an avalanche while riding below a short, steep, wind-loaded and rocky slope. While the avalanche only slid 300-400 feet vertically, it propagated almost 2100' across the slope. The set-up for this avalanche was not that different from the situation you could find in Togwotee, especially tomorrow. A slab of new snow sitting on a very weak layer, made worse by wind loading high on a ridgeline. There are many take-aways from the accident that will be available in a forth-coming report but several jump to mind.   

  • Route finding matters alot. When remote triggering is possible, which is the case whenever you have a deep and sensitive weak layer, give slopes a wide berth.
  • Rescue skills matter. Shovel and probe belong on your back, not your sled. This may not have changed the outcome in this incident, but seconds count. The victim, whose hand and feet were out of the snow, asphyxiated in 4-5 minutes.

Regioni coperte