Turnagain Pass Avalanche Forecast

The snowpack in and around Turnagain Pass is tired, stiff and needs a good re-fresh. A little snow did fall last night, a trace in some places with 1-2″ in others. With a sunny day ahead, keep in mind that we are still concerned about a weak layer 1-2′ below the surface. This is the notorious Nov 16th buried surface hoar (image below). Although we have not seen an avalanche release in this layer for almost a week, there are many slopes away from the ‘popular’ zones that have yet to be tested. These are the areas most suspect. 

The good news is, with time triggering an avalanche becomes less and less likely. During the past couple weeks the slab above the weak layer has been ‘faceting‘ away with the cold temperatures. This process turns the slab into loose unconsolidated snow and removes it from the equation; a ‘slab’ is a necessary ingredient for a slab avalanche. The other side of the coin is where the winds have formed new slabs over the weak layer. These are the areas to be most concerned about and look for if you head into the more remote zones. To be clear, we know that most of the high traffic slopes folks have been skiing/riding avalanched weeks ago and have been filled back in, this is why those slopes are generally stable. A tricky situation when heading for fresh lines in the back bowls! 

Photo: The notorious Nov 16 buried surface hoar found in Seattle Creek drainage yesterday where an old wind slab remained. The steeper slopes above harbored loose faceted snow (no slab) as mentioned above.

There is a significant amount of wind affected snow out in the mountains and on our favorite slopes. Ridgelines sport wind slabs, wind crusts, scoured areas that are covered by an inch or two of fluffy new snow. That said, there are still many pockets of sheltered soft settled powder that can be found. 

Watch for fresh shallow wind drifted snow today. We saw drifts along Seattle Ridge yesterday and although they were touchy, they were too small to affect a person. In areas with more snow and wind, the slabs could be large enough to knock you off your feet. The most concerning aspect is getting on a wind slab that breaks deeper in the pack in the buried surface hoar. Older wind slabs are stubborn but a person could still pop one out on steep rocky terrain where slabs have no support from below.

Photo: Wind affected snow on Seattle Ridge.