Two snowmobilers were racing up a snow-covered backcountry mountain when, suddenly, deep cracks appeared around the one leading the way. Snow poured down the slope, swallowing the second rider.

It could have been deadly. But both snowmobilers survived the Feb. 11 incident in Colorado’s Birdseye Gulch near Leadville, the highest-elevation town in the United States. Their close call was captured on video and shared on Facebook over the weekend by the Colorado Avalanche Information Center.

“He was buried up to his neck," center director Ethan Greene told The Washington Post. "So a few inches or a foot more of snow, and it would have been a very serious situation.”

The video shows the danger avalanches can pose to adventurers in backcountry parts of Colorado. Heavy snowfall this month has caused “moderate” to “considerable” avalanche danger in the areas around Aspen, Telluride and Breckenridge, according to the Avalanche Information Center, which has issued forecasts for nearly 50 years.

Avalanches happen when weaker layers of snow collapse under added weight, Greene said, likening it to a floor of an apartment building giving out after others are added. Since 1950, avalanches have killed more people in Colorado than any other natural hazard, reports the Avalanche Information Center, with 287 deaths in all. The state far outweighs the rest of the country, accounting for a third of the avalanche deaths.

In recent weeks, Colorado has seen what Greene called “kind of tricky avalanche conditions” due to the structure of the snowpack and the continued snowfall.

On Feb. 16, two men riding snowbikes — similar to dirt bikes, but made for traversing snow — died after accidentally setting off an avalanche north of Vail. The snow piled into a gully, burying the two in eight to 10 feet of snow, according to a report by the Avalanche Information Center. The Vail Daily News identified them as Dillon Block, 28, and Cesar Almanza-Hernandez, 30.

Yesterday February 15, three motorized snowbike riders were caught in an avalanche east of Red and White Mountain in...

Posted by Colorado Avalanche Information Center - CAIC on Sunday, February 16, 2020

A Vail local who was in the area described trying to help the trapped snowbikers.

“Between 10 of us, we each dug and dug for hours,” Hunter Schleper wrote in a Facebook post. He added, "It was clear that there was no chance of survival from early on.”

Greene said the fatal and the near-fatal avalanche accidents demonstrate the importance of checking the forecast, carrying rescue equipment including transceivers, probes and shovels, and having an understanding of the dangers.

He said the Avalanche Information Center shared the video of the two snowmobilers, which “is very close to being something very different,” to try to help build awareness among those who seek out backcountry experiences. With a little knowledge, he said, the risks can be managed.

“The reason people go out there is these are amazing environments,” Greene said. “They’re beautiful, they’re rugged, they’re challenging, and people are looking for that type of experience. And avalanches are just one of many hazards out there.”

Read more:

An injured trail runner tied shoes to his knees and crawled for 10 hours until help arrived

NASA’s Mars lander discovers quakes and a surprising magnetic field

A couple vanished in the woods on Valentine’s Day. More than a week later, they were found alive.