CAIC: Colorado Avalanche Information Center

2018/12/18 - Colorado - West Fork of Clear Creek, north of Jones Pass

Published 2018/12/24 by Jason Konigsberg - Forecaster, CAIC

Avalanche Details

  • Location: West Fork of Clear Creek, north of Jones Pass
  • State: Colorado
  • Date: 2018/12/18
  • Time: 11:00 AM (Estimated)
  • Summary Description: 1 backcountry skier caught, partially buried, and injured
  • Primary Activity: Backcountry Tourer
  • Primary Travel Mode: Ski
  • Location Setting: Backcountry


  • Caught: 1
  • Partially Buried, Non-Critical: 1
  • Partially Buried, Critical: 0
  • Fully Buried: 0
  • Injured: 1
  • Killed: 0


  • Type: HS
  • Trigger: AS - Skier
  • Trigger (subcode): r - A remote avalanche released by the indicated trigger
  • Size - Relative to Path: R2
  • Size - Destructive Force: D2
  • Sliding Surface: O - Within Old Snow


  • Slope Aspect: SE
  • Site Elevation: 12400 ft
  • Slope Angle: 40 °
  • Slope Characteristic: Gully/Couloir

Avalanche Comments

The avalanche was a hard slab avalanche remotely triggered by a skier, medium sized relative to the path and had the destructive force to bury, injure or kill a person (HS-ASr-R2-D2-O). The avalanche likely failed on a layer of faceted snow near the ground that formed in mid-November. Rescuers estimated that the crown face ranged from 24 inches to 96 inches. The avalanche released on a southeast-facing slope around 40 degrees in steepness.

Weather Summary

An early season snow storm affected northern Colorado at the end of October and into early November. From October 30, 2018 to November 5, 2018 the snow height increased 18 inches at the Jones Pass SNOTEL site (elevation 10,400 ft, 2.6 miles southwest of the accident site). A dry period of weather followed for the next two weeks before a series of storms brought about a foot of snow to the area from November 22 to 25. Small snowfall events continued through the first half of December. The last snow height increase prior to the accident was 2 inches on December 12 at the Jones Pass SNOTEL site.

Winds during the second week of December were generally light until the morning of December 11. On the 11th winds increased out of the northwest at the Berthoud Pass CAIC weather station (elevation 11,861 ft, 6 miles east of the accident site). There were sustained speeds of 40 to 50 mph with gusts of 50 to 70 mph. The winds stayed at these speeds for over 24 hours before decreasing to moderate speeds during the day on December 12. 

Snowpack Summary

Snow from the late-October storm faceted during the dry weather of mid-November. The faceting of early season snow was widespread in the Northern Mountains. This layer of faceted snow crystals was buried by a storm in late November, after Thanksgiving. Avalanche activity followed, with 32 avalanches recorded in the Front Range zone from November 22 to December 1. Avalanche activity breaking on the faceted layer tapered off in December without any major loading events. The wind event on December 12 resulted in intense snow transport and the development of hard slabs of wind-drifted snow on easterly aspects near ridge lines. 

Events Leading to the Avalanche

Two friends went ski touring on Tuesday, December 10. They started from the Jones Pass trailhead. Their goal was to reach a high point on the ridge at the top of the West Fork of Clear Creek drainage. They ascended low-angle slopes to reach an unnamed peak at 12,666 feet in elevation. On the ascent they did not observe any cracking in the snow or whumpfing sounds.

Accident Summary

Skier 1 descended from the peak and made about twelve turns. Skier 1 tucked beneath a large rock outcrop and yelled for Skier 2 to begin skiing. After about two turns Skier 2 noticed a large crack in the snow which started about 15 feet to his left and shot further to the left. Skier 2 turned to the right and looked downhill. He saw that a large avalanche had released about 30 to 50 feet below his location. From Skier 2's location he could not see Skier 1 in his waiting spot but he did see a large amount of snow flowing over the rock outcrop Skier 1 was sheltering below. Skier 2 looked for Skier 1 but did not see him in the avalanche or after the avalanche stopped.

Rescue Summary

Skier 2 descended the path looking for clues to Skier 1's location. He did not see any. Skier 2 reached the avalanche debris and began calling for Skier 1. A short time later he heard a response from Skier 1. Skier 2 continued to yell and hear a response. He followed the sound of Skier 1's replies. Skier 2 noticed something small and colored sticking out of the snow. It was Skier 1's head.

Skier 1 was buried from his neck down. Skier 2 dug out Skier 1 and assessed his injuries. Both Skier 1 and Skier 2 have first responder or higher medical training. Skier 2 concluded that Skier 1 had likely suffered a leg fracture and needed help.

Skier 2 gave Skier 1 as much extra clothing as possible and left to find help. Skier 2 heard a snowmobile in the area and skied towards the snowmobile. He tracked down the snowmobiler to ask for help. The snowmobiler rode to the trailhead. There he got in his vehicle and drove about a half mile down the road to a construction trailer. From the trailer the snowmobiler was able to call 911 and ask for assistance. The Clear Creek County Sheriff's Office and Alpine Rescue Team were notified of the accident and dispatched to the Jones Pass trailhead.

Clear Creek County and Alpine Rescue Team personnel traveled from the trailhead towards Jones Pass in a snowcat. The snowmobiler that made the 911 call guided them towards the accident site. The snowcat was not able to get all the way to the site. They were joined by other rescue team members on snowmobiles and continued up the drainage.

After contacting the snowmoibler, Skier 2 went back up to Skier 1. Skier 2 eventually heard the rescue team snowmobiles and skied towards the sound. He guided them to the accident site where they assessed the patient. The rescue team decided to transport Skier 1 to a hospital and called Flight for Life. They moved Skier 1 to a location where the helicopter could land and he was flown to a medical facility.