First hand account of Nov 16 Hourglass avalanche.

Location Name: 
Tamarack Pk - Hourglass Bowl
Region: 
Mount Rose Area
Date and time of avalanche (best estimate if unknown): 
Thu, 11/16/2017 - 09:00
Location Map: 
United States
39° 19' 10.1064" N, 119° 55' 17.5584" W
US


Red Flags: 
Recent loading by new snow, wind, or rain
Obvious avalanche path

Observation made by: Public
Avalanche Observations
Avalanche Type: 
Dry
Slab
Number of people caught: 
2
Number of partial burials: 
2
More detailed information about the avalanche: 

First hand account of incident, submitted by public user to SAC on Nov 21. Additional observations specific to this avalanche including snowpack info are listed here.

"After last Thursday's avalanche on hourglass most of us went deep into work and came up for air on Sunday with time to write up the incident.  Sorry for the delay.  

Thanks for all the great work you do.

Here's what happened............

Hourglass Avalanche

Thursday, November 16 – 9AM

Our party of four skinned to the top of Hourglass near Mt. Tamarack in storm conditions to ski and snowboard for the morning.  We had all checked weather and avalanche conditions and discussed the fluctuations of temperatures and winds overnight which painted a clear picture of high avalanche conditions and a wet morning in the storm.  There were 3-4 vehicles in the pullout when we arrived. We followed an existing track to the summit. The skin up was a normal storm approach with plenty of wind, and a few layers obvious with our pole plants. We did one traverse and switchback at the top of the bowl to the south with a similar aspect, gradient and elevation to the hourglass and had no results and noted no settling whomping or shooting cracks.

On top of the peak we met another party that had already completed at least one run in the bowl of the right Hourglass with similar aspect and elevation as the left hourglass. They made no comments regarding stability.  We discussed our lines and while one of us had skied the left bowl of Hourglass the previous day, the rest had not.  The one who skied the previous day decided to drop in that same line followed by one other.  Myself and the fourth person in our party decided on the low angle rib between the bowls.  The two on the left bowl skied one at a time, the first did a ski cut below the cornice line with no apparent results then dropped in.  When the second person cleared the choke at the bottom I dropped into the rib and stopped at the prominent rock dividing the chokes of each bowl.  The fourth then snowboarded down to me.  After stopping he flipped his board around and the snow around us settled and a few cracks emerged.  Being on the flat part of the ridge, nothing moved.  I looked down to see the first person in our party stopped at the bottom of the run, at the toe of the apron, switching back to skin mode.  The second person was about 100 feet above him still skiing down in the low angle run out.  I looked back up to the top of the bowl about 800 ft above us and saw it release.  I whistled twice and not seeing a response, I yelled “avalanche” twice where upon the one switching over began to run to the side and the other still skiing, began to ski off to the side.  Before they could get to the side of the slide path the wind blast hit them.  We spotted the location of each of them, watched the snow cloud settle and realized both were not visible.  

With the cracks around us and the possibility of a slide as we dropped below the rock, we kept our beacons on transmit and spotted each other as we leap frogged down to the lower angle terrain below the rock.  We took note of no hang fire looming above the slide path where our friends were buried.  As we approached the bottom of the slide path where the two were last seen, the person skiing had dug herself out  and the person switching over had his head and one arm out.  My partner checked in with her and determining she was OK we quickly made our way down to the one buried and dug him out.  

The person who was still skiing when the avalanche hit her was blown out of her skis and  they were buried.  She may have hit a tree and her back began seizing up .  The person buried had both skis but lost a pole and one skin and had a torn ligament in his ankle.  This situation became our larger dilemma as we had two low notches to climb out in deep snow with one injured ankle and seizing back, only one pair of skis which had only one skin (the other skis had a different interface to the skins), and all of us were wet from the storm and digging.  As we probed for gear the two caught in the slide had the shock wear off and the cold seeped in and they could no longer generate enough body heat.  They put on all the extra clothes we had and we began the long slog out sharing skis, splitboards, and packing out the easiest skin track we could.

A few take-aways:

1. We do not know if the bowl, at that particular moment, released naturally, the two who had skied it had a delayed release, my partner and I triggered it remotely or another party above was responsible.  If it was a remote trigger, something we are all well aware of, it became clear how far that trigger can travel - estimated at several hundred feet.

2. Gearing up in a safe zone can be helpful, which in this case was about 15 to the skier’s right and would have saved the person at the bottom switching over.  The switch over spot is also where anyone following steers towards as the finish their run, helping to save the second person.

3. Safe zones are key.  Knowing what a safe zone looks like and riding/skiing from one to the other helped us here.

4. Spotting each other saved us all.  Had we witnessed the slide from the top, there was no way our voices could have alerted them. The voice alert may have played a major role in increasing their chances of survival.

5. In our group we feel comfortable not always following each other and there’s never pressure to do so.  This allowed us to not all be in the slide path at the same time.

6. We succumbed to some common heuristic traps, familiarity with the terrain, no noted instabilities, previous skiers on slope and did not give adequate weight to the possibility of near ground faceting, lack of early season skier compaction and not having allowed the significant amount of new snow to settle adequately.

7. Luck is a rare resource and we all feel we used a few gallons of it this day."