Lawinenlagebericht

Togwotee Pass

Bridger-Teton Avalanche Center
Auf der Karte ansehen

Lawinengefahr

Mon
Hochgebirge
2 · Mässig
Waldgrenze
2 · Mässig
Unterhalb
Keine Stufe
Veraltet — dieser Lagebericht ist 4 years ago abgelaufen. Du siehst vergangene Verhältnisse, nicht den aktuellen Bericht.

Kernpunkte

Firm wind slabs in the upper elevations remain the primary avalanche concern. Look for isolated terrain features where wind has deposited snow creating drifts and stiffened surfaces. Although less likely, triggering deeper slabs on weak layers buried throughout the snowpack remains possible. Keep an eye on changing snow instability as temperatures increase throughout the day. 

Yesterday a skier triggered a D2 avalanche south of JHMR above No Name Canyon  in the Teton Forecast Zone while riding complex terrain, carrying them over cliffs and requiring a full helicopter rescue from TCSAR. 

Lawinenprobleme

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1–2.5

    Buried weak layers continue to haunt our snowpack. Avalanche activity on these layers has decreased over time, but the poor structure still exists with propagating test results in snow pits. These weak layers are scattered throughout the entire snowpack creating poor overall structure. This low probability, high consequence type of avalanche problem is difficult to manage. Areas with a shallower snowpack generally have a weaker snowpack that should be a concern due to the trends of human triggered avalanches this season. These areas also need a firm, cohesive slab to avalanche. Dig down and identify these weak layers before committing to complex and consequential terrain. 

     

    (2/5/2023)

    This recent avalanche failed on weaker snow near the base of the snowpack.

    Photo: Dawson Hatch

  • Wind Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1–2

    Snow from Feb 8th has been accompanied by moderate to strong primarily westerly winds of varying direction over the last several days creating firm, cohesive slabs. Most slab will be less than a foot deep, but could be up to 2 feet deep in heavily wind deposited terrain. These slabs will be confined to the upper elevations mainly on easterly aspects in areas with obvious wind effect in the form of scoured and deposited snow. Look for these slabs on exposed ridgelines, above cliff features and confined spaces such as couloirs. The avalanche yesterday on No Name Canyon has not been investigated, but appears to have some influence of wind slabs based on photos and proximity to the ridgeline.  

    Monitor rapidly changing conditions as rising temperature throughout the day increases the overall reactivity of the snowpack. Look for obvious signs of instability such as wet surfaces, rollers, and natural point triggers. Wet loose activity could be seen in very isolated terrain features on southerly aspects near cliffs and rocks. 

     

    (2/11/2023)

    Wind slab on West Angle that likely has some solar influence increasing reactivity. 

Avalanche Discussion

The forecast area has not seen any new snow since Feb 8th, yet human triggered avalanches are still occurring. This is due to the fairly widespread wind effect in the upper elevations that has created reactive wind slabs in isolated terrain. As good weather continues, skiers and riders are venturing into more obscure and hard to reach terrain. This is a natural progression as backcountry users gain knowledge of the snowpack and expand their terrain choices. Fresh tracks also become more elusive. Don’t let these human factors cloud your judgment though. Stay humble and remember that new terrain requires a new perspective. The variability of our current snowpack requires constant reassessment in new terrain, with a high amount of uncertainty in snowpack structure within all three forecast zones. Look for those avalanche problems described above as you travel through terrain, dig down in the snow, and monitor the snowpack during changing conditions such as increased temperature. 

 

Abgedeckte Regionen