Turnagain Pass and Girdwood

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

  2–3

  The set up in Turnagain Pass was already upside down with 2' of heavy snow from Monday's storm sitting on weak snow (near surface facets). Today another foot or more of snow, and rain below 2,000' with strong wind is adding more stress. This is a day to let the mountains adjust to this new load even if the storm moves out before the sun sets.

  Dry snow avalanches: By the time the sun comes up the mountains will have recieved over 1" of new water (10 to 12" of new snow above 2,000') since last night. This is a 'rapid load' and a red flag. Storm snow avalanches are very likely during the precipitation period and shortly after it turns off (24 to 48 hours). These avalanches could be 1' deep with just the new snow or 3' deep or more taking Monday's storm snow as well. 

  With ridgetop winds blowing in the 20s and 30s mph wind slab avalanches are likely occurring and could be 2 to 4' deep or more depending on how much of the snowpack they bring along for the ride.

  If all that wasn't enough, cornices will be growing and they tend to be reactive during  periods of warm and intense weather. A cornice fall could trigger a large slab avalanche, which is another reason to stay away from avalanche terrain and runout zones today.

  Wet snow avalanches: We don't  know if the amount of rain falling on the current surface crust below 2,000' will be enough to melt it away, but if it does, there will be good chances a person could trigger a wet avalanche including loose wet and potentially a wet slab. Roller balls and lack of a surface crust will be the indicators that this has become a problem.

  Glide avalanches: The last full glide avalanche (there was a partial release last week on Tincan) we know of was December 22 east of Girdwood near Kern Creek. There have been many reports since then of glide cracks moving slowly downhill so we are keeping this on our radar.