Turnagain Pass

A few new observations of glide avalanches came in from Seattle Creek yesterday, but the exact timing of when they released is uncertain. Otherwise no new avalanche activity was reported.

Two recently released glide avalanches on the far side of Seattle Creek. Photo from Troy Tempel 12.28.2023

Today promises to bring another day of cold and clear weather with very light winds. Yesterday, we observed some active wind transport on higher elevation ridgelines which could form small wind slabs 1-2′ deep in exposed areas. These fresh wind slabs are mixed in with widespread wind affected snow along upper elevation ridgelines from the stormy weather over the weekend, which could make them difficult to identify. Keep an eye out for shooting cracks in small pockets of wind transported snow that could be sensitive to the weight of a skier or rider. These avalanches are probably too small to bury a person but could easily knock you off balance in steep terrain.

Prior to the storm last weekend there was a widespread layer of surface hoar on the surface that we have been searching for in the snowpack because of the potential to cause avalanches at the storm snow interface, which is roughly 2′ deep. So far our field observations have not turned up any concerning results at this interface, but it is worth keeping in mind if you are venturing into new terrain today. Surface hoar can be difficult to identify visually in a snow pit, but tends to reveal itself if you use a compression test or extended column test to check the stability of the snowpack in the area you are travelling.

Dry loose avalanches are very likely in steep wind sheltered terrain. We recommend making a plan to manage your sluff if you are travelling in steep and complex terrain.

Wind affected snow surfaces along upper elevation ridgelines could produce a surprise avalanche in steep terrain. Photo 12.28.2023

Over the past week or 10 days there has been a notable spike in the number of glide avalanche releases across the region. This type of avalanche is not well understood. All we really know is that they can spontaneously release under any conditions and when they release they take the entire snowpack and are highly destructive. The glide avalanche on Cornbiscuit on Wednesday was roughly 5-6′ deep and ran almost all the way to Bertha Creek. The short story is that you definitely do not want to mess with this type of avalanche and we strongly recommend giving glide cracks a wide berth and minimizing the amount of time you spend underneath them. Take a careful look at the slopes above you and consider setting a new skin track or riding off the beaten path if you can find a way to avoid travelling underneath glide cracks.

It was sobering to peer into this recent glide release and see the destruction it caused in the runout zone. Photo 12.28.2023

The facets over the Thanksgiving crust are still lingering 4-6′ deep in the snowpack. The lack of recent avalanche activity on this layer despite many storm systems adding stress over the past few weeks is a good indicator that the layer is dormant, but we are continuing to monitor it due to the history of crusts producing very large avalanches in our region. It is possible that layers like this can re-activate later in the season if the snowpack structure becomes weaker or if melt water pools on top of the crust. Hopefully continued snowfall will bury this crust so deeply that we can soon remove it from the forecast.