On Monday, Hilaree Nelson, 49, slipped and appeared to fall into a 2,000ft (600m) gap in the ice, known as a crevasse, only 15 minutes after reaching the summit of the 26,781ft peak, reported BBC.
Ms Nelson had earlier in the day scaled the summit of Mount Manaslu — the world’s eigth tallest peak — in Nepal with her partner Jim Morrison.
The couple had taken photos with their three Sherpa guides, who used a satellite phone to share the good news with Jiban Ghimire, owner of Shangri-La Nepal Trek, the outfitter that organized their expedition, reported The New York Times.
After climbing the summit, they made their way down from the 8,163-metre (26,781-foot) peak.
Fifteen minutes later the guides reportedly radioed Mr Ghimire again and said: “Big problem.”
Other climbers who were with the couple said that “her ski blade skidded off and [she] fell off the other side of the peak”.
It is not known whether Ms Nelson survived the fall. After the incident, Mr Morrison was able to make it back to base camp, reports said.
The couple are among the most accomplished alpinists and backcountry skiers in the world.
Ms Nelson is a North Face-sponsored athlete who has two children and is based out of Colorado.
“With a career spanning two decades that includes dozens of first descents through more than 40 expeditions to 16 different countries, Hilaree Nelson is the most prolific ski mountaineer of her generation,” North Face said about the mountaineer on their website.
While Ms Nelson has been a guide herself on several of Nepal’s highest peaks, weather conditions changed quickly on Monday, as they often do in high mountain ranges.
On foot, “it takes three days to reach the incident site from base camp”, said Mr Ghimire.
“Weather is hampering search and rescue operations.”
He added that the company would send out a helicopter on Tuesday morning to the crevasse where Ms Nelson disappeared. He added that Mr Morrison is in good health and will be on the helicopter for the rescue mission if the weather is conducive to flying.
In a separate incident on Monday an avalanche on Mount Manaslu swept away climbers, porters and Sherpas, killing one and reportedly injuring 14 others.
Authorities have not yet been able to launch helicopters to reach the stranded group.
In 2019, an avalanche on Mount Manaslu killed nine climbers.
In 1972, another avalanche killed 16 climbers.