Eastside Region

Lawinenprobleme

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  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Very Likely

  Größe

  1.5–3

  Winds are expected to continue at strong to extreme speeds today. You can expect continued slab development throughout the day and resulting wind slabs are likely to be large and reactive. While most concerning near and above treeline, Strong winds can redistribute snow in unexpected ways. Don’t be surprised to find reactive wind deposits in relatively sheltered areas below treeline and further down slopes than you may typically expect to find them. Be suspect of terrain features that encourage drifting such as the leeward sides of ridgelines, gully features, and cross-loaded depressions.  Large to very large natural and human-triggered avalanches are likely today. Avalanches may run long distances and into lower angle, or treed terrain you may typically think of as “safe”.

  

• 

  Storm Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Possible

  Größe

  1–2

  Snowfall rates during the last 48 hrs hit periods of well over 2” an hour and storm totals over 70” have been recorded throughout the range. This recent storm snow is expected to gain strength relatively quickly today, however, avalanches breaking within the new snow are likely to be large in size. Approach steep terrain over 30° today with caution and be cognizant of your exposure to terrain features that increase the consequences of avalanches. This includes road cuts, gully features, cliff bands, and mid-slope depressions.

  

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  Deep Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Unlikely

  Größe

  3–3.5

  The weight of a skier or rider is not likely to be enough today. A larger trigger such as a wind slab avalanche or large cornice break will be necessary to trigger a deep slab avalanche. While unlikely, an avalanche breaking near the ground has the potential to be very large and destructive. Steep and unsupported slopes, large avalanche paths, and areas with shallow trigger points, are areas to consider. Uncertainty around deep slab instabilities is very high and managing this problem requires extensive evaluation and deliberate terrain choice. Deep slab avalanches often fail without warning, they can propagate across and beyond terrain features that would otherwise confine surface instabilities such as wind or storm slabs, and in some cases avalanches can be remotely triggered from adjacent slopes. Give yourself a wide safety margin, be wary of hazards that may reside above you, and use terrain choice to limit your exposure.