Lawinenlagebericht

Snake River Range

Bridger-Teton Avalanche Center
Auf der Karte ansehen

Lawinengefahr

Thu
Hochgebirge
2 · Mässig
Waldgrenze
2 · Mässig
Unterhalb
1 · Gering
Open full map
Veraltet — dieser Lagebericht ist 6 months ago abgelaufen. Du siehst vergangene Verhältnisse, nicht den aktuellen Bericht.

Kernpunkte

Triggering a large hard slab avalanche that fails on buried weak layers is possible in very steep, north facing terrain above 8,000’ today. Signs of instability will likely not be present, so avoiding suspect slopes is key. Watch for shallow wind slab formation above 9,500’ as wind speeds increase this afternoon. 

Lawinenprobleme

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1.5–3

    Weak layers of snow including surface hoar and facets are buried 2-4 feet below the surface on shaded slopes. While the sensitivity of this layer is decreasing, riders may still be able to trigger a large, hard slab avalanche in very steep terrain over 35 degrees. Northerly aspects above 8,000’ are where this layer is weakest and where the majority of recent persistent slab activity has been observed. Signs of instability including fresh avalanches and collapses in the snowpack may not be present before triggering. Giving very steep, north facing slopes a wide margin is the best way to manage hazard right now due to the difficult to predict nature of this problem, and the high consequence of triggering an avalanche of this size.

    Wind speeds are expected to increase slightly this afternoon. Be on the lookout for shallow pockets of newly formed wind slab if travelling above 9,500’ today. These slabs will be small, but could knock a rider off their feet in consequential terrain. 

    A large natural persistent slab avalanche that happened around the last storm 2/25.

     

Avalanche Discussion

Warm, spring-like weather continues today. A good overnight freeze and some cloud cover today should limit wet snow instabilities. However, avoid steep, south facing terrain if surface crusts break down and the upper foot of the snowpack becomes wet and unconsolidated. 

While it certainly feels like spring has come early, cold snow and persistent weak layers remain on north facing slopes above 8,000’. These weak layers are slowly gaining strength, but have not changed as quickly as the weather. Large human triggered avalanches involving weak snow from January were reported within the past week. The snow from our February storms has settled and become strong, making it difficult to impact the weak snow underneath. Despite this, there are still thin spots in the overlying slab where a rider may be able to trigger an avalanche. Very steep, north facing slopes are the bullseye for instability. Use caution and build some margin into your travel plans around these terrain features for the time being.

Abgedeckte Regionen