Lethal avalanche may have caught Fort Collins men just as it began to dissipate
January 26, 2012
Steamboat Springs — The avalanche that claimed the life of 24-year-old Tyler Lundstedt, of Fort Collins, on Saturday night or Sunday morning started well below the tree line, fell 140 vertical feet and was of moderate power.
"It broke into old snow and was about 2 feet at the deepest," Ethan Greene, director of the Colorado Avalanche Information Center said Wednesday evening.
Greene and a companion spent most of the day Tuesday at the scene assessing snow conditions and the terrain in the vicinity of the avalanche path. Greene ultimately will write a report about the fatal avalanche, but it won't be complete until he can interview the victim's brother Jordan Lundstedt, 21. Jordan Lundstedt partially was buried in the avalanche but survived after extricating himself from the snow. He located his brother by using an avalanche beacon but not in time to rescue him.
"We won't really know what happened until I can talk to him," Greene said. But after examining their tracks leading into the slide path, he concluded the two men may have decided they were climbing higher than they should have in avalanche country and made a course change shortly before the avalanche struck them. The two men were on foot after abandoning a snowmobile and were presumed to be trying to return to a parking area near the Grizzly Creek Campground on the opposite side of Buffalo Pass and the Continental Divide from Steamboat Springs.
"They were climbing out of a creek and along a bench in a climbing traverse," Greene said. "I can't say for certain, but it looked like they had recognized they were moving up into steeper terrain and started to go back down, and that's when they triggered the avalanche."
Greene and his companion snowmobiled in as far as they could on Jackson County Road 43D and skied the rest of the way to the scene.
They soon observed the three primary signs that they were in an area of potential avalanche hazard. They spied recent larger avalanches on steeper terrain than the one that struck the Lundstedts. They observed cracking and collapses in the slope they were on, and they heard a telltale "whoomphing" sound.
"We had all of those," Greene said. "We were very careful. We climbed up to the fracture line to inspect it, but we did it in such a way as to not expose ourselves. We were very worried there could still be another avalanche."
The avalanche ran down a north-facing slope at 9,400 feet with only a few trees. Greene described it as being "a little bit concave," possibly with a rocky outcropping at the top and taller elevations on either side.
Avalanche experts gauge the size and force of an avalanche with two scales, each running from one to five, with one being the mildest and five the greatest, Greene said.
The R factor weights the avalanche with regard to its size relative to the path it followed. An R-4 is an avalanche that widens the boundaries of a path and an R-5 is big enough to make a path of its own. This was an R-3.
"It was a good-sized avalanche for that path," Greene said.
The second measurement, the D scale, describes the force of an avalanche. The Chedsey Creek slide was a D-2.
"It was deep enough to kill someone. It had enough force to kill somebody. A car might have been pushed around by that slide, but it wouldn't have been" heavily damaged, Greene said.
The debris from the slide included some broken tree branches, but it was not strong enough to break tree trunks. He described it as a hard slab avalanche of moderate density.
"It's what we could call a hard slab because of some of the debris we saw," Greene said. "There were chunks of hard snow that survived the avalanche. But it wasn't like (what one might see on) Berthoud Pass where gusty winds form super hard slabs."
Avalanche experts measure the hardness of slabs with a simple hand test. If you can punch your fist into the hard crust, it's at the moderate end of the scale. The test continues using four fingers, one finger, a pencil and finally a knife. The Chedsey Creek slabs were hard.
"The snow on top was fist hard, but as you went down, it was one-finger slab chunks."
Greene said the two men weren't carried more than 10 feet by the avalanche.
That's due in part, he said, to something that isn't typical of human-triggered avalanches but is indicative of current conditions and something the Avalanche Information Center has been warning the public about for much of the winter.
The three phases of an avalanche are the start zone, the path and the run-out, where the slope decreases to the extent that the avalanche slows and finally stops.
The Lundstedt brothers were close to the beginning of the run-out when the avalanche overtook them.
"They triggered it from right where the debris starts to pile up, which is unusual but fits with this snow structure," Greene said. "We've been saying for weeks it's possible to trigger avalanches from lower-angle slopes. We've been worried about this scenario happening more than in other years."
— To reach Tom Ross, call 970-871-4205 or tross@SteamboatToday.com