Avalanche Details
- Location: East Vail, backcountry southeast of Vail Ski Area
- State: Colorado
- Date: 2014/01/07
- Time:
11:15 AM
- Summary Description: 4 riders caught, 1 injured, 1 killed
- Primary Activity: Sidecountry Rider
- Primary Travel Mode: Ski
- Location Setting: Accessed BC from Ski Area
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Number
- Caught: 4
- Partially Buried, Non-Critical: 0
- Partially Buried, Critical: 2
- Fully Buried: 0
- Injured: 2
- Killed: 1
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Avalanche
- Type: HS
- Trigger: AS - Skier
- Trigger (subcode): u - An unintentional release
- Size - Relative to Path: R3
- Size - Destructive Force: D3
- Sliding Surface: O - Within Old Snow
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Site
- Slope Aspect: E
- Site Elevation: 11600 ft
- Slope Angle: 36 °
- Slope Characteristic: Planar Slope
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Avalanche Comments
This was a hard slab avalanche, triggered by a skier or snowboarder, medium size for the avalanche path but large enough to destroy a timber structure, and broke into old snow layers (HS-AS-R3-D3-O). The avalanche broke at the top of a layer of depth hoar, which was the lowest layer in the snowpack. It stepped down to the ground below the first cliff band. The avalanche spanned two adjacent avalanche paths. The crown face was 4 to 6 feet (measured) near the western flank, but at least 10 feet deep near the center (estimated). The avalanche was close to 900 feet wide and ran 1463 feet vertically. There was some tree destruction along the lower portion of the path. One broken tree found near the bottom of the path was close to 12 inches in diameter. Other broken tree branches were 4 to 6 inches in diameter.
Weather Summary
Skies were clear at the time of the accident, but clouds were building to the southeast. There had been no new snow at the nearby Vail Ski Patrol Headquarters (PHQ) over the past 24 hours. Winds at PHQ were light from the northwest.
From the 6 AM weather observation at Vail Ski Patrol headquarters on January 1, to the 6 AM observation on January 6, 18.5 inches of new snow (HN) had fallen. The snow had a water content (HNW) of 1.91 inches. Over that period, winds were consistently strong from the west and northwest.
Snowpack Summary
Early season snow from October and November had formed a weak basal layer of 4 mm depth hoar grains along the rim of the East Vail Chutes. Periods of snowfall in early and late December buried the depth hoar. Another period of snowfall occurred January 1 to 6. Northwest winds were noted as '"exceptionally strong," during that period, creating wind drifts 1 to 4 feet deep. The East Vail Chutes are particularly prone to wind loading from west and northwest winds.
At the time of the accident, a hard slab of snow ranging from three to ten feet thick rested on a layer of depth hoar along the rim of the East Vail Chutes. A similar snowpack structure had become reactive to skier-triggering across the Front Range and Vail/Summit forecast zones over the two weeks prior to the January 7 accident.
Events Leading to the Avalanche
A group of four sidecountry riders assembled on the morning of January 7 (Group 1, Riders are numbered by the order of their descent). All four were equipped with avalanche safety equipment, and were aware of the danger ratings in the CAIC forecast. They were all familiar with the terrain in the East Vail Chutes.
Rider 3 and Rider 4 met at the base of Gondola 1 in Vail Village at 9 a.m. They rode lifts to the top of Vail Ski Area's Chair 4 and went inside a restaurant to wait for Rider 2. After meeting Rider 2 the group proceeded to the bottom of Platter Lift 22 and met Rider 1. The group put on skins and ascended to the top of 11,816 foot Red (also known as Abrahams) at about 11:15 a.m.
Rider 1 and Rider 2 descended an avalanche path known as Tweeners. Tweeners is the northern-most of the three adjacent avalanche paths. Then they traversed south, to their right, and stopped on the left flank of an avalanche path known as Nothing But Air (NBA). Rider 2 stopped along the southern edge of a group of medium sized spruce trees, and took out a camera and prepared to take some pictures. Rider 1 traversed about 30 to 50 feet further south, or rider’s right, along a line of small trees that ran along the top of a cliff band.
From the summit of Red, Riders 3 and 4 skied down the ridge approximately 100 ft. They stopped on the ridge above Rider 2's location. Rider 3 descended next, made several turns, and stopped to the left of Rider 1’s location. Rider 4 began their descent to the rider’s right of Rider 3. Rider 4 made several turns before cutting left, crossing Rider 3's track and stopping just below Rider 2. Rider 2 began to place his camera into his pack, partially zipping it closed. At this moment Rider 1 was looking upslope and saw a fracture open, then everyone heard a loud 'Boom'.
Accident Summary
Instantly all four riders were caught in the avalanche.
The avalanche swept Rider 1 over the cliffs. Rider 1 came to a stop against a large spruce tree. Rider 1’s head was buried about 12 inches deep (partial burial-critical).
Rider 2 was caught a few feet south of the left flank. The avalanche swept Rider 2 30 to 40 ft down slope before going over the cliff. After landing, Rider 2 was swept another 25 to 35 feet down slope. One leg was under avalanche debris when the avalanche stopped.
Rider 3 briefly held onto a small tree before being swept over the cliffs and coming to rest on a rock ledge. Rider 3 lost both skis and a pole.
Rider 4 was swept down slope over the cliff band before coming to rest against a large spruce tree. Rider 4 was about 50 to 75 feet below Rider 2, and at about the same elevation as Rider 1.
Rescue Summary
Riders 1, 2, and 3 quickly established voice contact. They quickly realized that Rider 4 was unaccounted for. The group yelled to turn their avalanche transceivers to receive. Rider 2’s transceiver read 25, Rider 1’s 37. Meanwhile Rider 3, highest on the slope, began to work their way down through the cliff band before traversing left towards Rider 2.
Rider 2 saw Rider 4's boots and a ski pole above the avalanche debris. The group raced to this location and began to excavate Rider 4. The group found Rider 4 unresponsive and began CPR. A member of Group 1 called 911 at 11:45 a.m.
Another party, Group 2, was a distance to the north and witnessed the avalanche. Group 2 knew Group 1 was planning to descend the area of the avalanche. They called a member of Group 1 and were told that they had been caught in an avalanche. Group 2 called Vail Ski Patrol.
About 15 minutes after the avalanche, Rider 5 was standing at the top of Red and got a phone call from a friend asking if they were in East Vail and “ok.” Rider 5 said “yes,” and was told to look for a large avalanche. Rider 5 saw no recent activity to the north, so proceeded south, down to Tweeners. Rider 5 saw the avalanche debris, and soon had voice contact with Group 1. Rider 5 assisted with first aid.
Vail Ski Patrol and Vail Mountain Rescue evacuated the party members and recovered Rider 4’s body.
Comments
The East Vail Chutes are popular and easily accessed avalanche paths adjacent to the Vail Ski Area. These chutes are comprised of a number of avalanche paths with unofficial names. The high point of the East Vail Chutes is called Red on the USGS quadrant map Red Cliff. Locals have several names for this point, most common are “Abraham's” and “Siberia Peak.” The first avalanche path to the south, or riders right, of Red is “Tweeners”. Tweeners has a narrow choke through a cliff band. South, or rider’s right, of Tweeners is “Nothing But Air” (NBA). NBA often has a convex wind roll at the top. The slope angle is less than 35 degrees near the rider’s left tree line. The slope angles steepen to the south, towards “Charlies Death Chute” (CDC). The avalanche spanned NBA and CDC. An avalanche fatality occurred in CDC on January 4, 2008, and in NBA on December 3, 1992.
This area is rimmed with several sandstone cliff bands. Depth hoar commonly forms in and above the cliffs in the late fall and early winter. To the west of the ridge is a large, open area with a few trees. This is a prime fetch for snow transport. Snow drifts build rapidly at the top of the avalanche paths when the area sees moderate to strong west and northwest winds. The wind drifts taper thinner below the ridge. Hard slab avalanches are often triggered from areas of shallower snow, where a rider can more easily effect the weak layers.
Media
Video
Images
Snowpits
Figure 20: A fracture-line profile from the north side of the crown.