Turnagain Pass and Girdwood

Lawinenprobleme

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Likely

  Größe

  1.5–2.5

  Under the skiff of new snow from last night and winds affecting the surfaces is that Valentine's Day buried surface hoar. This weak layer is buried roughly 1 to 2 feet deep and still reactive in places, darnit. There were two parties out on Tincan yesterday that triggered small avalanches on test slopes (pictured here and another photo below). This is a clear sign it can create a larger avalanche on larger slopes.

  If you've been reading along over the last week you'll know this layer caused up to 10 human-triggered avalanches on the backside of Seattle Ridge a week ago (ish). Many of these were triggered remotely (from above or near the slope). The tricky part is, it has shown to be less reactive and not seen on all slopes on the non-motorized side of Turnagain. This makes it really hard to know if a slope is 'OK' or not... For now however, with natural wind slabs and cornice falls happening due to the weather, it's a safe bet to just avoid those bigger slopes, but when the skies clear this issue will make getting onto steeper terrain safely quite tough.

  

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Hochgebirge
  • Waldgrenze
  • Unterhalb der Waldgrenze

  Wahrscheinlichkeit

  Likely

  Größe

  1–2

  The easterly winds ramped up yesterday, have continued overnight, and should remain through today. They are averaging 20-30 mph and gusting near 40-50. They have been accompanied by a trace to a couple inches of snow across the region overnight. Yesterday we saw two natural cornice falls off the Magnum ridgeline and can guess there were others. They did not trigger wind slabs below that we could see, but this also could be happening elsewhere.

  That all said, fresh wind slab avalanches and cornice falls will be likely in the upper elevations. These of course can occur naturally and will be easy for a person to trigger. Wind slabs could be up to 2 feet deep, and even deeper in highly wind loaded spots. Watching for active wind loading and cracking in the snow around you will be key if the skies open a bit today for travel into the upper elevations. Definitely give cornices a wide berth. They have been growing again with this weather and are notorious for breaking off further back than expected. 

  Loose snow avalanches: Dry sluffs should be expected in the upper terrin where dry snow exists. Wet or damp sluffs are likely below 2,000' where the snow is warmer and wetter. 

  Glide Avalanches: Glide cracks are still on the move, and we still don't know when they will release. These avalanches are very large and very unpredictable. The only way to manage them is to avoid spending time under open glide cracks.