Turnagain Pass

Wind slabs: Over the last few days several wind events combined with over a foot of new snow have created wind slabs up to 20” thick on leeward features. The good news is this new snow seems to be bonding well with the old snow below, however not enough time has passed for this hazard to have completely healed. Yesterday we received reports of skiers triggering pockets of wind slab on steep wind-loaded slopes. Trigging an isolated wind slab in the wrong place, like over a cliff or above a terrain trap, could have high consequences. As wind slabs get older they get stiffer and may allow for travel out onto them before they release. Watch for shooting cracks and avoid hollow sounding snow.

Cornices: Already large cornices have received additional stress from the new snow load and strong winds earlier in the week. These have a tendency to break farther back than expected and can send you for an undesirable ride.  Approach ridgelines with caution and avoid being on or directly below cornices features. 

Image from FS National Avalanche Center.

In places protected by the wind 12” of loose unconsolidated snow could be fast moving in steep terrain. Loose snow can easily knock a person off of their feet or take them for a ride over a cliff or into a terrain trap. Manage your ‘sluff’ and avoid terrain features with high consequences. Skiers have reported being surprised by these conditions over the past couple days. 

Today at Treeline (the 1,000’ – 2,500’ elevation band) on all aspects, pay attention to and AVOID glide cracks. These can lead to glide avalanches that are very unpredictable as we have seen over the past few days. Yesterday there was a large release on the South face of Sharks Fin. The cracks on Corn Biscuit were recently observed and continue to grow.  There is no discernable pattern to predict a failure, as they tend to fail naturally and on their own schedule. Warm temperatures can trigger them and so can cooling temperatures. Cracks can form and release in seconds or days later or sometimes a glide crack won’t release at all. The new snow has made it harder to see the existing cracks and glide releases in the terrain. 

It is best to give glide cracks a wide berth.  AVOID spending time underneath and if skiing or riding in terrain with glide cracks, try and map them out before your travels so as not to end up directly on top of or inside one.  Remember, when these do fail, they tend to be destructive, failing to the ground and bringing the entirety of the snowpack with them.

Don’t mess with the ‘Brown Frown’!!!