Windslab Avalanche on Hawkins Peak

The goal of the day was to ski a north facing gully in Woodfords canyon. We had 6 members in the group. Skiers A & B were friends with skiers C & D and skiers E & F, but Skiers C & D had never met Skiers E & F before. The general plan was to skin up Merk canyon and down a north facing couloir, with skiing back down the skin track as a backup option if the couloir did not look good. 

On arriving at the parking lot, it was much windier than expected and we could see active wind transport up high and down low. Skiers A, C and D had skied the couloir before and knew of a lower angle, somewhat scoured side entrance into the couloir.

On the skin up, we observed windy conditions, active wind transport, sheltered cold snow, and wind-affected snow and sastrugi in a variety of places at a variety of elevations and aspects.

Upon arriving at the transition point, Skier A kicked at the edge of a steep windloaded roll over. There was a pencil hard layer of windboard that only cracked when kicking above the skin track, where it was already undercut. These cracks were 7 inches deep and 2 feet long. Skier A did not discuss his thoughts about this test slope with the whole group.

The main entrance to the line was a steep leeward bowl, with a second slightly less steep entrance on the skiers’ right side. The less steep, somewhat scoured side entrance was further down and to skiers’ right. This side entrance was not connected to the upper part of the steeper bowl. After the top pitch, the line mellows out before steepening again at the bottom.

Skier A suggested they ski the lower, somewhat scoured side entrance. Skier B expressed concern about the windloading and skiing below the steep, leeward bowl in a terrain trap. Skier F brought up the unknown steeper terrain at the bottom of the line. The group talked briefly about managing/avoiding the windslab problem by taking the lower entrance and finding safer spots off to the side. There was not a clear consensus about what it would look like or how easy it would be to manage avalanche hazards given the windloading and terrain. The loose plan was to ski down through the lower, somewhat scoured entrance one at a time to an undesignated safe spot in the trees below, before continuing down. No one suggested or requested an alternative to skiing this line.

After transitioning, Skier E skied down to the start of the lower angle entrance. Skier A decided to ski cut the upper right hand side of the bowl near where he kicked earlier. This snow was very firm and the ski cut produced no results. Skiers A, B, E & F approached the entrance to the lower angle entrance. 

Skiers C & D were standing on top of the center of the upper bowl, left of Skier A’s ski cut. Skier C yelled down and signaled to Skier A, asking if he thought skiing the main bowl would be ok. Skier A could not hear due to the wind and did not reply. Believing the lack of results from Skier A’s ski cut to be a green-light, Skier C then skied straight down the middle of the bowl and down to the safe spot. Skiers E & F then skied down the lower-angle, somewhat scoured side entrance to an out-of-sight safe spot with Skier C. 

Skier D then skied into the upper bowl from the far right side, where the slope was slightly less steep, towards skier C’s tracks. Once Skier D had traversed into the bowl, the slab fractured across most of the bowl and approximately 50 ft above Skier D. Skier D slide down approximately 200 feet and stopped on top of the debris. Skier D was uninjured, had all his equipment, and was able hike up the lower-angle entrance to where Skiers A & B were standing on a rock outcropping.

The slide was about 150 ft wide. The crown appeared to vary from about 8 inches deep to as much as 2-3 ft deep. The whole slide ran about 350 vertical feet.

Skier D called skiers C, E, & F. They were unaware of the slide. We reformulated a plan for the lower skiers to skin back up to the group and descent down the skin track. 

Some additional notes from our debrief. 

• Skier A didn’t share his thoughts about the test-slope or ski cut with the whole group. The group did not collectively discuss the characteristics of a hard slab.
• At the top of the line, the group did not carefully discuss how high winds and active wind transport might impact the appropriateness of the terrain for the day.
• Neither Skier B nor Skier F, who both expressed questions/reservations about the terrain, suggested a clear alternative or insisted on their concerns. These were the only two women in the group, and neither had skied this zone before.
• Skier C put too much stock in Skier A’s ski cut. In hindsight, a ski cut in a hard slab where there was compressive support didn’t give much information about the stability. 
• Skier A was initially upset at Skier C center-punching the bowl, but discounted this thought since it didn’t slide. 
• Skier D shared he wouldn’t have skied the line he did, if not for Skier C skiing it first. He also shared that he somewhat rationalized skiing that line since it had a shorter steep pitch and got less steep fairly quickly. 
• Skier A almost said something to Skier D before he dropped in about avoiding that line and coming down to the lower-angle entrance that the group initially talked about. He regrets not saying anything.
• There is uncertainty as to why the slab broke on Skier D instead of Skier C. One possible explanation is that Skier C may have unknowingly skied over the thickest part of the slab, while Skier D skied over a shallower part. It could have also just been luck.
• High winds made communication and decision-making in a spread out group much harder. Radios would have been helpful.
• Skiers A and C had previously skied the entrance that Skier D took today on moderately windy days and avoided the windslab on those days. This terrain familiarity created a false sense of security that contributed to Skier D skiing the line he did. 
• The larger group and lack of existing relationships between some members detracted from our ability to make strong plans with clearly-defined alternatives and consensus about what conditions would trigger those alternatives.
• Skiers A, B, E, & F drove more than 90 minutes to ski this zone, which contributed to continuing with the plan after higher-than-expected winds at the car.