Seward and Lost Lake

Problemi valanghivi

• 

  Storm Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Very Likely

  Dimensione

  1.5–2.5

  Recent avalanches: Large natural avalanches were observed near Girdwood and at Crescent Lake in the Summit Zone yesterday. We expect natural avalanches have also been occurring in the Seward zone due to heavy precipitation, very strong winds, and a very weak snowpack. 

  Very dangerous avalanche conditions exist throughout the region. Please avoid travel in avalanche terrain. Natural avalanches are likely, and human-triggered avalanches are very likely.  The current snowpack (see Problem 2) can be triggered remotely from flat terrain below, and avalanches will likely run down to valley bottoms. The atmospheric river pointed the fire hose at southcentral Alaska yesterday and overnight. There is a buffet of avalanche issues in the mountains today, all good reasons to find alternative activities to mountain recreation.  With 2+ feet of new snow at upper elevations and more forecast to fall today, storm slabs will be sensitive and easy to trigger.  Easterly winds have been strong and sustained, helping build large wind slabs in the alpine. Below approximately 1500', where rain has been falling, wet loose avalanches could also be a concern.  An avalanche failing in the upper snowpack may also step down to the buried weak layer, creating a much larger avalanche. 

  Upper elevation estimated storm totals since Wednesday night are listed below:

     Snowfall  Snow Water Equivalent (SWE)  Girdwood  2-3'  3.0  Portage  2-3'  3.0  Turnagain  1-2'  1.4  Summit  1-2'  1.4  Seward  2-3'  2.5

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Very Likely

  Dimensione

  2–3

  There is a very well-documented layer of weak snow that formed in December, now buried 2 to 4' deep, as my good friend Wendy liked to say, "funny business" in the snowpack. We are very concerned about avalanches failing on this layer and being very large and connected. These have the potential to be very dangerous and destructive. There were multiple human-triggered avalanches on this layer in Turnagain over the past week, and the snowpack in the Seward zone is very similar. The heavy precipitation and wind loading are now adding stress to it, and knowing this spooky weak layer is lurking is a great reason to steer clear of avalanche terrain altogether.