Togwotee Pass

Lawinenprobleme

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  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Likely

  Größe

  1–2

  Above freezing temperatures and clearing clear skies will make natural and human-triggered wet avalanches possible on steep slopes that face the sun today. The majority of these avalanches will be on the smaller side, yet some could knock a person over in consequential terrain. These avalanches are most likely to begin around rocks or trees and can entrain large amounts of snow as they move downhill. Temperatures climbed to almost 50 degrees on the pass yesterday and only dipped to the mid 20s F overnight. Any surface crusts will break down quickly as the day warms, leading to unstable conditions on sunny slopes. Be on the lookout for signs of warming, such as natural wet avalanches or slushy unconsolidated snow. Consider moving to shaded, low-angle terrain if these signs are present. Carefully evaluate the terrain above you, given the potential for natural activity.

  

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  Deep Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Possible

  Größe

  1.5–3

  Weak layers of sugary facets exist in the middle of the snowpack and near the ground on most slopes. Avalanches involving these layers will be 2-3 feet deep and up to 5 feet deep on heavily wind-affected slopes. Triggering one of these dangerous avalanches is possible on very steep slopes over 35 degrees. Signs of instability such as cracking, collapsing, or recent avalanches may not be present before triggering a large avalanche capable of propagating long distances. Multiple tracks on a slope do not indicate stability with this problem type. Suspect terrain includes very steep, rocky, and/or wind-affected slopes where thin spots exist, making it possible for humans to impact buried weak layers.

  Above freezing temperatures and recent loading has stressed these buried weak layers and could increase the likelihood of triggering a persistent slab avalanche. Surface slabs could step down to deeper weak layers resulting in a larger avalanche than expected.

  

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  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Possible

  Größe

  1–2

  Wind slabs formed over the past weekend by moderate westerly winds and new snow at upper elevations. Warming temps and a soft overnight freeze in many locations could increase the sensitivity of these older slabs during the heat of the day. These slabs could fail at the old storm interface buried on 3/13 and be up to 2 feet deep on very steep  (>35°), wind-loaded slopes at upper elevations. Likely trigger spots include convex starting zones, cross-loaded couloirs, and steep terrain below cliff bands. Carefully evaluate steep, upper-elevation terrain for signs of unstable wind-drifted snow, such as cracking or hollow-sounding snow. Consider moving to lower-angle terrain if these signs are present or if snow surfaces become wet.

  Cornices are sensitive right now with these warm temperatures. Minimize time spent on slopes with large cornices looming overhead. They can break unexpectedly and act as very large triggers.