Avalanche Details
- Location: Gunsight Mountain, Elkhorn Mountains
- State: Oregon
- Date: 2024/03/06
- Time:
4:30 PM
(Estimated)
- Summary Description: 1 backcountry skier caught, not buried, and killed
- Primary Activity: Backcountry Tourer
- Primary Travel Mode: Ski
- Location Setting: Backcountry
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Number
- Caught: 1
- Partially Buried, Non-Critical: 0
- Partially Buried, Critical: 0
- Fully Buried: 0
- Injured: 0
- Killed: 1
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Avalanche
- Type: HS
- Trigger: AS - Skier
- Trigger (subcode): u - An unintentional release
- Size - Relative to Path: R4
- Size - Destructive Force: D3
- Sliding Surface: O - Within Old Snow
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Site
- Slope Aspect: N
- Site Elevation: --
- Slope Angle: 47 °
- Slope Characteristic: --
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Avalanche Comments
At approximately 1630 on Wednesday, March 6th, a backcountry skier was killed in an avalanche near Anthony Lakes Ski Area. The accident occurred on the north side of Gunsight Mountain (8342') and involved two skiers. Skier 1 was able to descend the prominent north-facing couloir on Gunsight without incident. Skier 2 triggered the avalanche near the top of the couloir. He was caught, carried, deployed his airbag, and came to rest on the surface of the snow. Skier 1 called 911 and performed life-saving measures. A small group of bystanders assembled in the Anthony Lakes parking lot and assisted Skier 1. Unfortunately, the victim succumbed to injuries at the site. The avalanche failed on a layer of weak, faceted snow and is classified as HS-ASu-R4-D3-O.
Backcountry Avalanche Forecast
There was no forecast in effect on March 6th, 2024. The Wallowa Avalanche Center posts avalanche forecasts with danger ratings Thursday - Sunday and general advisories Monday - Wednesday (these are products without a danger rating).
The general advisory in effect from March 4th - March 6th stated:
Bottom Line: 2-3' of new snow has fallen over the last week, much of this snow fell with moderate winds out of the South. Near and above treeline, storm slabs and wind slabs need time to settle and bond. Carefully evaluate any slope over 30 degrees before committing to riding it.
Discussion: A storm beginning on Monday (2/26), has brought consistent snowfall to the forecast area. The first 4 days of this storm brought moderate to strong winds out of the SE, S and SW. These winds loaded snow onto E through NW slopes. During this storm cycle, natural and human-triggered avalanches have occurred. The past three days winds have decreased and nice low-density snow has continued to fall. This new snow has obscured some signs of wind loading and wind slabs- we must remember that they are still there.
The snowfall is forecasted to continue through Tuesday afternoon. Wednesday looks to be a cool, sunny day with light winds. A prime day to get out into the mountains and perhaps approach some larger objectives. Use caution and carefully evaluate the snowpack, terrain, and consequences of taking a ride before committing to consequential terrain.
Besides wind and storm slabs, we have a few layers of unstable snow buried in the snow to be cautious of. When the Storm began well-developed surface hoar was everywhere. Slopes facing east, south, and west had a melt-freeze crust on them. During the storm, several layers of graupel were deposited. Please read more about these layers below.
Surface Hoar- The layer of surface hoar buried on 2/26 has been found in the Elkhorns, Southern Wallowas and Northern Wallowas. Propagating results were observed in Extended Column Tests on this layer on Saturday (3/2) 50cm down. Sunday (3/3) I found buried surface hoar mixed with graupel sitting on top of the 2/26 crust at 7500' on a NE facing slope in the Northern Wallowas down 80cm. This layer failed in a Compression Test and propagated in an Extended Column Test in extra innings (more than 30 hard whacks from the shoulder). While the distribution of these layers is patchy, it does exist and is reactive. Before riding terrain over 30 degrees with steep convexities it is advised to dig down to look for this layer. A layer of surface hoar buried on Valentine's Day was also found in the Southern Wallowas (3/2).
Graupel- This storm has brought a lot of graupel with it. Graupel is small round BB's of snow, it can look like hail. As you can imagine, a layer of BB's isn't very stable. Storm Slabs were reported failing Saturday (3/2) on a layer of buried graupel 30cm down. These layers of graupel are another source of uncertainty. When our uncertainty increases, our margins of safety should increase too. Make conservative terrain choices and dig down into the snow to look for layers of graupel which could be the weak layer for an avalanche.
In summary: The riding is really good! A major storm cycle is in the process of ending. The weather is going to clear and call us to step out and step up. New snow avalanche problems are present. There are buried weak layers in the snowpack. Use caution and careful evaluation before getting on steep terrain.
Weather Summary
Seasonal snowfall and precipitation data are from the Bourne SNOTEL site at 5,850’, 8.6 miles SE of the accident site, and the Anthony Lake Snolite site at 7,160’ .6 miles N of the accident site. Wind data are from the Anthony Lakes weather station located 1 mile NW of the accident site at 7,979’.
Unfortunately, the Anthony Lakes anemometer stopped recording wind speed and direction on the morning of March 2nd and remained out of service through the afternoon of March 7th.
Starting on January 27th, a warm front pushed through the region, ultimately elevating snow levels to above 8,000 feet. Between the morning of January 27th and the evening of January 31st, temperatures at the Anthony Lakes weather station remained above freezing. During this time, the Bourne Snotel site recorded 1.1” of SWE and the snowpack received rain on snow.
February brought a total of 37” of snow to the Anthony Lake Snolite site while Bourne recorded 3.6” of SWE.
A significant storm system began impacting Northeastern Oregon’s mountains on Monday, February 26th. By March 1st, the Anthony Lake Snolite site had received 17” of snow and the Bourne Snotel had recorded 1.2” of SWE. Between March 1st and the morning of March 5th as the snowfall ended, Anthony Lake Snolite picked up 3” of snow and the Bourne Snotel recorded .6” of SWE
Between February 26th and 28th, temperatures stayed in the single digits to teens (F) before peaking at 26 degrees late morning on the 28th. Temperatures steadily declined with a stretch of sustained cold temperatures in the teens to single digits through the evening of March 6th.
Between the evening of February 28th through February 29th, winds were sustained in the moderate to strong category from the Southeast with gusts in the 50 to 60 mph range. Wind speeds tapered from the afternoon of February 29th through the morning of March 1st. Winds increased again mid-morning on March 1st and continued to blow out of the SE in the moderate to strong category with gusts up to 50 mph. The wind then shifted out of the SW early morning on March 2nd and started to decrease.
Snowpack Summary
The avalanche occurred on a north-facing slope at 8,342’. The average slope angle of the start zone was 47 degrees with a maximum slope angle of 50 degrees. The initial avalanche was 30 feet wide, 1.5-2 feet deep on average, and ran 1100 vertical feet from the top of the couloir. Besides the initial crown, there were additional crowns all failing on the same weak snow layer, which measured up to 7 feet deep (Figure 7). The avalanche is classified as HS-ASu-R4-D3-O.
The snowpack at the crown of the avalanche consisted of a very hard (Knife) bed surface, with a weak layer of (4F) 1mm faceted grains sitting below a slab consisting of (1F) hard snow (Figure 9). A warmup between January 27th and 31st created the hard bed surface the avalanche released on. Nearby weather stations remained above freezing during this period, snow levels were above 8,000’ and the snowpack received rain on snow. The Bourne snotel received 0.7” of SWE from January 26-27th, but it came in the form of rain. Temperatures cooled in early February and a trickle of snow lasted through February 11th, with 1.3” of SWE recorded at the Bourne snotel and 9” of snow at Anthony Lakes. Temperatures were cold during February 1-11, which accounted for the facets that formed above the hard crust.
In the Elkhorn Mountains, the end of February into early March brought a significant storm with HIGH danger in the alpine between February 29 and March 2. On Sunday, March 3 the danger was rated CONSIDERABLE. This was the last day that a danger rating was issued before the fatal avalanche occurred. From February 26th to March 6th there was an increase in snow height at the Anthony Lakes Snolite station of 20”. The Bourne Snotel recorded 1.8” of SWE during this same time.
Accident Summary
A group of 3 departed from the Anthony Lakes parking lot and skinned up into Angell Basin to Lees Peak. A separate group of 2 was planning on meeting up with the first group. They arrived at the parking lot after the first party had departed. They radioed the first group and confirmed they were headed to Lees Peak. As the second group of 2 skinned up to Lees Peak they noted no signs of instability. The second group caught up with the group of 3 at the bottom of the run after skiing Lees Peak. This was the last day of a backcountry ski trip for 2 of the people in Group 1 as they had plans to return home. At this point, all 5 people went back to the Anthony Lakes parking lot.
The group was getting ready to leave when Skier 2 stated he wanted to ski more. Skier 1 said he would go with Skier 2 and they decided to ski Gunsight Mountain. The other 3 people headed down from Anthony Lakes. Skier 1 and Skier 2 started climbing up into Angell Basin towards Gunsight Mountain around 15:30. Upon arriving at Hoffer Lake, Skiers 1 and 2 ran into a solo skier. They talked with the solo skier, who said he would watch them descend off Gunsight Mountain from the parking lot. Skier 1 and Skier 2 kept climbing to the top of Gunsight Mountain, arriving a little before 16:30. They decided that Skier 1 would ski first, riding through the couloir and regrouping out of the runout, then radio up to Skier 2 when he was clear. Skier 1 side stepped up skiers left of the top of the couloir to get some speed and execute a ski cut across the top of the ski run. There were no results. Skier 1 then skied the couloir and stopped clear of the runout in a safe location on the bench where he could see Skier 2 at the top of the run. Skier 1 radioed to Skier 2 and told him he was in a safe spot and Skier 2 started to descend. Skier 1 could not see the full length of the couloir but could see when Skier 2 began. Skier 2 made approximately 4-6 turns when the avalanche released. He was caught in the avalanche and pulled his airbag. Skier 1 lost sight of skier 2. A large powder cloud began to form and the slope directly below the bench skier 1 was standing on released as the avalanche moved past. Once the snow stopped moving, Skier 1 turned towards the Anthony Lakes parking lot and yelled “avalanche” twice.
Rescue Summary
Skier 1 switched his transceiver to search and did not have a signal. He dropped over the large lower left crown (4-5 ft in height) and traversed out into the middle of the path. He spotted Skier 2’s ski pole, then immediately looked downslope and located Skier 2 on the surface of the avalanche debris (Figures 5, 6). Skier 2 was not buried. Skier 1 reached Skier 2 within 1 minute. He removed his skis and began to assist Skier 2 who was injured.
The solo skier who spoke with Skiers 1 and 2 as they were approaching Gunsight Mountain observed the avalanche from the Anthony Lakes Parking Lot. He went into the lodge, called 911, and had an employee of Anthony Lakes stay on the phone with Baker County Dispatch. At this point, he went to the lower parking lot to look for help. A group of friends who were staying at the mountain (Bystanders 1,2,3), two of whom had personal snowmobiles (Bystanders 1 and 2), and a nurse (Bystander 3) began mobilizing towards the avalanche. As Bystander 3 was headed out to the accident site she encountered a physician (Bystander 4) who was staying at one of the yurts on the mountain and asked him to help. The solo skier also made it to the accident site.
At 16:36, Skier 1 called 911 while he was attending to Skier 2. Skier 1 provided the dispatcher with coordinates. He began to hear snowmobiles and moved Skier 2 down the hill. At 16:55 he encountered one of the the bystanders. Bystander 1 helped Skier 1 move Skier 2 further down the hill. Skier 1 and Bystander 1 started CPR as 4 other bystanders arrived. They performed CPR for approximately 30 minutes. At 17:16, a deputy from the Baker County Sheriff's Department arrived at the Anthony Lakes parking lot along with the local Life Flight Helicopter. Bystander 4 (the physician) made the call to stop CPR and pronounced Skier 2 deceased at 17:55. Bystander 1 rode his snowmobile back to the parking lot to update the local sheriff's department and SAR. Bystander 1 came back with a sked. They packaged Skier 2 and got him to a groomed road where a UTV was waiting with the Baker County Sheriff. All members of the bystander responder group and Skier 1 returned to the Anthony Lakes lodge to talk to the Baker Country Search and Rescue and the Baker County Sheriff.
Comments
Fatal avalanche accidents are tragic events. We do our best to describe each accident to help the people involved, and the community as a whole, to better understand them.
Both skiers were experienced backcountry travelers and had completed a Professional Level 2 or equivalent training course. They both carried avalanche transceivers, shovels, and probes and Skier 2 was wearing an airbag. Skier 2 was an avalanche forecaster and avalanche educator who was skiing for personal recreation at the time of the accident. To our knowledge, no other avalanches were observed either natural or human triggered on the layer that failed in this accident.
Victor McNeil of the Wallowa Avalanche Center, along with forecasters Kelly McNeil, Caleb Merrill, and Michael Hatch obtained details of the accident through interviews with group members.
Any questions should be directed to:
Victor McNeil
Executive Director
Wallowa Avalanche Center
Media
Images
Snowpits
Figure 10: Snowpit profile from the highest crown of the avalanche. Observed and recorded two days after the avalanche.
Figure 11: Snowpit profile observed and recorded one day following the avalanche. The location was 5 meters skier’s right of the lowest crown of the avalanche in undisturbed snow.