Turnagain Pass

It has been several days since a 3-day storm with high winds averaging 40mph subsided leaving behind stiff pockets of wind-loaded snow. There have been no recent reports of natural or human triggered avalanches, however the potential for triggering a wind slab in steep terrain still exists.

Wind slabs tend to be found in isolated pockets that can break above you. Avoid smooth pillow-like features on steep convexities, especially if high consequence terrain (rocks, trees, cliffs) is below you. Pay attention for shooting cracks or hollow sounding snow – these are obvious clues that a wind slab is unstable.

Evaluate the snow as you travel by probing with your ski pole to measure the stiffness and depth of the slab. Practice safe travel rituals like traveling one at a time in steep terrain and look for islands of safety to spot each other.  There are plenty of scoured ridges left behind from the 3-day wind event. Use these routes for safe travel into the alpine.

We have been actively tracking a buried surface hoar layer over the last two weeks. This layer is widespread throughout Turnagain Pass and has a 2-3’ slab sitting on top. The recent wind event has made the slab denser and more suportable. This is good news, as it will take more force to trigger this kind of avalanche. The bad news is the consequences are still high, and if you find the right spot it could propagate a large avalanche.

Avoid trigger points like shallow areas around rocks and convexities in steep terrain.  A cornice fall or wind slab avalanche could be enough weight to trigger a persistent slab. Give cornices a wide berth and pay attention to wind slabs in steep terrain as described in the primary concern.

An avalanche of this size could run into treeline. Keep in mind the runout zones and be aware of people traveling in steep terrain above you.