Quick report
- Slope Angle
- 40°
Avalanche
- Slab Width
- 30 m
- Weak Layer
- Facets
- Trigger Type
- Skier
- Vertical Fall
- 91 m
- Avalanche Type
- Soft Slab
- Slab Thickness
- 61 cm
- Trigger Detail
- Unintentionally Triggered
- Start Zone Aspect
- Southwest
- Avalanche Problem
- Persistent Weak Layer
- Start Zone Elevation
- 3018 m
SS-AS-D1-R1. While skinning up towards Pole-line/Cardiff pass, we noticed a small avalanche on the southwest side of the Flagstaff shoulder with one ski track entering the crown, and we were unable to see any ski tracks exiting the debris or slope. We shifted directions towards the avalanche, and once at the bottom still could not see any tracks exiting. Despite the small size of the avalanche, we were concerned about a potential hangup in the trees within the path for the involved party. We decided to send two from our group of 5 up to perform a transceiver signal search because it appeared that the individual may have been traveling alone. The remaining group members stayed in the flats, keeping eyes on the hanging snow above, and called Alta Central to inform them of the situation, so Alta Ski Patrol could standby if the signal search yielded results. We turned our beacons to search at the toe of the debris, and continued to switchback up the slope, spacing out ~50 feet. The debris in the open snow, for the most part, was not deep enough to bury a human. On the trees there was debris piled up to 7 feet deep.
After we reached the stauchwall(roughly) we were finally able to see a ski track exiting to the skier's right, through the trees, traversing far out on the slope away from the avalanche. Given the traversing nature of the track, it was almost impossible to see from a downhill angle. At this point, we put our transceivers back into send, and communicated the info back down to the rest of our party below so they could communicate back to Alta Central. Out of an abundance of caution, we sent one skier up to the uppermost trees, the last point where anyone involved in the avalanche could have been pinned. It seemed that the involved party had indeed arrested, pinned, or otherwise stopped against these trees, and then skied out. Hard to tell exactly, but this is my best guess. From here I traversed over to the crown to perform a quick profile, then skied back down to the rest of the group. Picture of the trees from uphill included below. Thankful there wasn't any serious involvement in this avalanche!
Photos below:
Photo 1: The whole scene, our skintrack up, and ski tracks down. If you look closely, you can see the involved parties exit track on the right side of the trees.
Photo 2: Crust step-down below the crown.
Photo 3: Looking up at the crown from the upper trees.
Photo 4: looking down at the upper trees
Photo 5: another photo of the avalanche