Summit Lake

Avalanche problems

• 

  Glide Cracks

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  2–3

  Cooling temperatures doesn't necessarily mean the glide activity will slow down. These avalanches are unpredictable, not human triggered, and could release at any time. We may sound like a broken record, but we recommend staying out from underneath glide cracks or "brown frowns" and their runout zones. These avalanches take the entire seasons snowpack to the ground and it would be difficult to survive being caught. The glide crack pictured here is in Turnagain, but there are many just like this in the Summit area.

  

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  2–3

  It's been several days since we have gotten any information from Summit Lake and the persistent slab avalanche problem is tricky. It may not give any warning signs before releasing. The poor structure (slab over weak snow) that produces this type of avalanche is widespread in the Summit area and the only way to completely avoid this problem is to stick to slopes less than 30 degrees.

  We don't know yet how the weak snow at the base of the snowpack is handling the weight of the new rain, snow and wind from the last few storms. The mountains in the Summit zone have wind scoured ridgelines like the one pictured here. However, there is plenty of snow in the gullies and on slopes protected from the wind that could produce a large avalanche as a result of the poor structure that exists. 

  

• 

  Wind Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Likely

  Size

  1–2

  A wind slab is the most likely problem that could get us into trouble in the alpine today. The wind is still blowing and could be creating fresh wind slabs throughout the day. These "pillows" of windblown snow are typically found below ridgelines and in gullies. A small test slope is a good way to see how the newly deposited snow is bonding to the old snow beneath. 

  These slabs could have different character since the wind has been blowing strong for several days with just a little bit of new snow. There could be touchy fresh wind slabs 1' deep or less or there could be a more stubborn wind slab that could be 2' deep from older blowing snow. There is a smaller chance of triggering one of these stubborn and larger wind slabs, but these are the ones that might let you get way out onto the slope before releasing above you.

  Wet loose: With temperatures cooling off, all of the wet snow in the mid elevations should be freezing and locking up into a crust, which makes wet avalanches unlikely. If you find yourself in a place with wet snow there could be a chance you could trigger a wet loose avalanche. These avalanches can be difficult to escape so watch for trees, cliffs, or gullies that you might get carried into if you were to get caught. 

  Rough guess at snowfall storm totals above 2,500' (7pm Tuesday to 6am Thursday):Girdwood Valley:  18"Portage Valley:  20 to 40"Turnagain Pass:  8"Summit lake:  1" Seward/Lost Lake:  6 to 10" close to the coast in the upper elevations