Turnagain Pass and Girdwood

Avalanche problems

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  2–3

  Recent avalanches: Following the widespread natural avalanche cycle last weekend, the most recent human-triggered avalanche occurred on Wednesday, Jan. 21 when a skier remotely triggered an avalanche on the front side of Sunburst, taking out several sets of existing ski tracks. There was also another goat-triggered avalanche near Girdwood yesterday.

  We're looking at another day of quiet weather with unusually warm temperatures at higher elevations, and not much has changed with the dangerous snowpack we've been dealing with. The problem is a layer of weak, faceted snow buried 2 to 4' deep that has been producing large avalanches, rolling collapses, and poor stability test results all week. This is not the typical new-snow avalanche problem we are used to, and it has been catching even experienced travelers by surprise. These persistent weak layers are slow to heal, and there is still a good chance a person will trigger a very large avalanche today.

  A few things to keep in mind as you plan your day:

  • Multiple avalanches have been triggered remotely over the past week, from flat terrain connected to steeper slopes.
  • We've seen people trigger avalanches that wiped out several sets of previous tracks.
  • The most recent known human-triggered avalanche occurred six days after the last major loading event.
  • The combination of a stiff slab sitting on top of a deeply buried weak layer means we may not see any warning signs (collapsing, shooting cracks, poor test results), even though conditions are primed to trigger a big avalanche.

  The best way to manage this challenging snowpack is to use simple, low-angle terrain. This includes limiting overhead terrain exposure, since multiple large avalanches have been triggered from the flats. It also means avoiding slopes with terrain traps, which increase the consequences of being caught in a slide. This extended spell of warm, quiet weather is slowly giving the snowpack time to adjust, but for now we are still tiptoeing around while the weak layer heals.

  Loose Snow Avalanches: Ice climbers have reported loose snow avalanches initiating in steep, rocky upper elevation start zones and running through gullies. While these have not been big enough to bury a person, they can pose a major threat if they were to pull you off of a climb. They will be most likely on steep solar aspects.