This avalanche was triggered by a solo powsurfer, a rider on a snowboard with no bindings, on Colorado Mines Peak (Mines Peak), east of Berthoud Pass, in an area locally known as High Trail Cliffs. High Trail Cliffs is a series of four steep, rocky, northwest-facing avalanche paths that are easily accessed from the parking area at the top of the pass. It was a hard slab avalanche. The avalanche was medium-sized relative to the path and destructive enough to injure, bury, or kill a person. It released on a weak layer of buried faceted crystals and stepped down to the ground, entraining the entire season’s snowpack (HS-ARu-R3-D2-G). The crown face averaged about 2 feet deep and was about 550 feet wide across all four of the avalanche paths in the High Trail Cliffs. The avalanche ran about 525 vertical feet through sparse trees and rocky terrain. The avalanche broke small trees, and the debris and broken limbs piled up on a bench below the slope. Debris was over 7 feet deep in places. Portions of the debris reached the historic maximum trimline of the avalanche path.

The Colorado Avalanche Information Center’s (CAIC) forecast for the area around Berthoud Pass for February 22, 2025, rated the avalanche danger at Considerable (Level 3 of 5) near and above treeline and Moderate (Level 2 of 5) below treeline. A Special Avalanche Advisory was in effect. The primary problem was Persistent Slab avalanches on west through north to east-facing aspects at all elevations, on southeast-facing slopes near and above treeline, and on south and southwest-facing aspects in the above treeline elevation band. The likelihood was Possible, and the expected size was large to very large (up to D3). The second problem was Loose Wet avalanches on southwest, south, and southeast-facing slopes near and below treeline. The likelihood was Likely, and the expected size was small (up to D1.5). The summary statement read:

A Special Avalanche Advisory is in effect from Friday evening through Sunday evening for most of the Front Range, the mountains of Summit County, and the Gore Range. Avalanche conditions are dangerous. You likely won't see or hear any warning signs before triggering a deeply breaking, deadly avalanche. Several big avalanches were triggered over the last few days after multiple tracks were placed on a slope. Avalanches can be triggered from flat areas below steep slopes and lower-angle connected slopes. To stay safe in these conditions, give suspect slopes a wide berth. Choose lower-angle terrain and smaller slopes without terrain traps.

There were a few small storms in October. There were scattered patches of snow in the trees on northwest-facing slopes. A series of storms led up to Thanksgiving, and a large storm from November 25 to 27, 2024. A snowpack started to form on northwest-facing slopes. The snow on the ground faceted and became weak in December before a stormy period from December 24 to January 6. That snow settled into a dense layer. There was another period of dry, cold weather, and another faceted layer formed in the surface snow. Small storms trickled in through the remainder of January and early February. It snowed almost every day from February 12 to February 21. The Winter Park Ski area, located 4 miles north of the accident site, recorded 71 inches of snow during this period. During the 48 hours preceding the accident, the CAIC Berthoud Pass weather station, 0.5 miles west of the accident site, recorded winds from the northeast with an average wind speed of 10 miles per hour and peak gusts of 30 miles per hour. It was clear and sunny on the day of the accident.

Rider 1 arrived at the Berthoud Pass parking lot around noon on February 22, 2025, for a day of powsurfing. He made a handful of runs in less steep terrain. Sometime before 4:30 PM, he skinned toward the top of Mines Peak and transitioned to his powsurfing board.

The High Trail Cliffs are visible for a long distance in both directions from US Highway 40 over Berthoud Pass. Multiple motorists witnessed the avalanche catch Rider 1, saw the size of the avalanche, and called 911. Grand County Sheriff’s Deputies, Grand County Search and Rescue (GCSAR), and a Flight For Life helicopter carrying an avalanche dog team from Breckenridge Ski Area were dispatched to the scene.

A family called 911 and continued driving downhill toward Winter Park. At the second hairpin turn on the north side of the pass, they saw two backcountry skiers (Rescuers 1 and 2) and alerted them to the accident. The skiers called another member of their party who was in the Berthoud Pass parking area and started skinning toward the avalanche site. The rider in the parking area and another recreationist who overheard the conversation (Rescuers 3 and 4) started toward the accident site as well.

It took the Rescuers 1 and 2 about 15 minutes to ascend from the road to the avalanche debris. They turned their avalanche rescue transceivers to search and got a faint signal. Rescuers 3 and 4 arrived about 20 minutes later. The four refined the search area to a deep pile of debris on a bench near the bottom of the avalanche path. Broken trees in the avalanche debris hindered searching. Two more backcountry skiers arrived, and the growing group continued to narrow down the signal. The transceiver signal was fluctuating, but they found a location where their transceivers indicated a 1.5 meter (5 feet) burial. They got a probe strike and started to dig through the dense debris. They uncovered Rider 1’s leg first and were eventually able to excavate his head. About an hour had passed since the avalanche, and there were no signs of life.

GCSAR transported the victim’s body back to the Berthoud parking area.

All of the fatal avalanche accidents we investigate are tragic events. We do our best to describe each accident to help the people involved, and the community as a whole, better understand them. We offer the following comments in the hope that they will help people avoid future avalanche accidents.

Traveling alone in the backcountry is riskier than traveling with a partner or in a group. Challenging situations or injuries that are more easily addressed by a team can be difficult or even insurmountable for an individual. Although difficult situations can be easier to manage with a group, there is nothing inherently wrong with traveling in the backcountry alone. People are drawn to the mountains by their beauty and the opportunity for adventure. We each choose how we want to face the challenges they offer and decide what is acceptable risk for ourselves. Traveling alone in avalanche terrain is not wrong, but it is a choice that allows little room for error.

Rider 1 was traveling alone but wearing an avalanche rescue transceiver. If you choose to accept the increased risk of traveling in the mountains alone, being searchable will help rescuers if you are involved in an accident. This puts fewer rescuers at risk because it is easier to find you. It decreases the time rescuers are exposed to danger and uses less of their very limited resources. In this event, members of the public went out of their way to assist in a rescue.

Members of the public who responded to the incident had difficulty locating a strong transceiver signal and had multiple phantom signals. It took them some time to rule out multiple burials. This could have been due to interference or an older transmitting or searching beacon. Checking that you are using up-to-date technology that is regularly serviced makes for maximal search efficiency. Understanding sources of signal interference and techniques to combat them is important.

The feature that Rider 1 chose to descend is a very visible piece of terrain close to the road. Other riders had put tracks in a separate gully north of the area where Rider 1 descended. Tracks on slopes and proximity to trailheads, ski area gates, or the road do not mean a slope is safe. The choice of terrain did, however, mean that the avalanche was witnessed and other travelers were able to respond, eliminating a long search but not avoiding a tragic outcome.