West Slopes Central

Lawinenprobleme

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  Storm Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Likely

  Größe

  1–2

  Observers reported touchy conditions over the last several days, with natural and human triggered avalanches occurring up to destructive size 2. Avalanches broke mainly on recent new/old snow interfaces one to two feet beneath the surface. After a brief period of blue skies and calm, snowfall intensity and wind are increasing throughout the day on Thursday. The danger is not expected to rise by the end of the day, but make note of changing weather conditions and how it is affecting the snow. 

  Snow that fell since the weekend was heavier than what fell at the start of the weekend. This caused an “upside down” snowpack, where the heavier snow is sitting over a lighter layer. These conditions are oftentimes alarming, as avalanches usually fail easily on the light snow, with the denser snow acting as a slab. Stay alert for this by noticing thicker surface snow which then punches down to the lighter underlying layer. This upside down snowpack is present and reactive throughout the zone. Additionally, you will find even more touchy conditions on leeward slopes at upper elevations where wind may have deposited snow into thicker and more reactive slabs. With both of these concerns, avoid slopes steeper than 35 degrees, especially ones with signs of wind loading, and consider traveling around the runouts of large steep slopes as well.

  

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  Deep Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Unlikely

  Größe

  2–3

  The mid January deep persistent layer is getting buried deeper making it more difficult to trigger, and observers are also finding that its strength is increasing. Over a week has passed since the last avalanche occurred on this layer. Despite this, keep it on your mind as you are traveling through the backcountry. An avalanche failing on this layer is unlikely, but even the smallest possibility is alarming. Uncertainty remains, and this weakness presents a very serious low likelihood/high consequence scenario. If you are in an avalanche which fails on this deep slab you would probably not survive. 

  Large triggers like cornices or motorized users have the best chance at affecting such a deeply buried weak layer. Continue to build in a wide margin for error and approach steep open slopes above 4500ft with a cautious mindset. Utilize good travel practices like riding one at a time and keeping eyes on your partners. If you must travel near or below steep upper elevation slopes, your best options are areas where avalanches on this layer already occurred.