Powerline Pass Trail

We toured down Powerline Pass to examine the hiker-triggered avalanche from yesterday. We accessed the slide path, conducted a flank crown profile, and captured video to help communicate current conditions.

The avalanche appears to have failed on multiple layers. We suspect an initial failure on a wind slab over weak facets, stepping down into deeper layers including December facets (~30 cm above ground) and basal depth hoar. At lower elevations, the avalanche likely entrained wet snow, transitioning into a wet component.

Debris was very firm—set up like concrete—and contained broken tree trunks and large blocks (some the size of mini fridges). This points to a deep, persistent slab failure with significant mass and destructive potential.

We conducted a crown profile at ~2,800' on a flank, avoiding the main crown due to hangfire concerns. Results were consistent with Alaska Mountain Rescue Group observations, highlighting two primary layers of concern: depth hoar and December facets. Moisture was present to the base of the snowpack, indicating water percolation and rounding of basal facets.

At lower elevations (~2,200'–2,400'), we were able to sink to the ground in lower-angle terrain, confirming a saturated and weakening snowpack.

We observed numerous wind slab avalanches in gullies on NE aspects along the Powerline Pass trail, many of which appeared filled in by subsequent wind transport. Aside from the two recent human-triggered avalanches, we suspect most of this activity occurred naturally during the major wind loading event late last week.