By the day's end, MacKenzie was sitting on a mountain with critical injuries suffered as he was carried nearly two kilometres down the slope in an avalanche, which struck late Thursday afternoon in a remote area near Pemberton.
Light was falling and the weather was deteriorating as MacKenzie, a 30-year-old patroller at the Whistler Blackcomb resort, waited with another skier for help.
That help came too late.
"It took a considerable amount of time for search-and-rescue ground crews to gain access and ultimately determine he had succumbed to his injuries," Sgt. Peter Thiessen of the RCMP said in an interview Friday.
"One of his close buddies remained with him on the cold, dark mountain waiting for help while his buddy was dying, and you can only imagine what that must have been like for that individual."
MacKenzie is the second person to die in an avalanche this season, which in recent days has been marked by heightened avalanche risks throughout much of British Columbia, including where the four skiers were on Thursday.
The avalanche occurred as the skiers were making their final descent of the day. The RCMP said MacKenzie was swept away and travelled about 1,800 metres down the mountainside.
When his companions found him, he was severely injured and unconscious, said the RCMP. One skier stayed with him and administered CPR, while the other two went for help.
Helicopters were dispatched from Canadian Forces Base Comox, but the remote terrain and poor weather prevented them from reaching the scene.
By the time a search crew arrived hours later, MacKenzie was dead.
Search-and-rescue personnel returned Friday afternoon and recovered MacKenzie's body, said Thiessen.
MacKenzie had worked at Whistler Blackcomb since October 2000.
"All four members of the party were highly skilled backcountry ski tourers," said the news release from the Whistler Blackcomb resort, which confirmed MacKenzie's identify.
"(MacKenzie) was a keen athlete and outdoor enthusiast."
Various online postings and websites identify MacKenzie as a frequent backcountry skier, who, in the off season, also built mountain-biking trails.
Eric Berger, a professional photographer, first met MacKenzie through his work photographing skiing for Whistler Blackcomb. He soon came to call MacKenzie a friend.
"He was a super-strong skier, and he was obviously passionate about the mountain," said Berger.
"He decided to pursue a career as a ski patroller on Whistler Mountain. It's not something you can just walk into; it requires a lot of dedicated and training. I think it's a testament to his knowledge and passion."
Berger said MacKenzie's death will be a huge loss for the skiing community in Whistler.
"He was a real positive guy, always positive and always smiling," he said.
"I've never seen him in a bad mood."
The Canadian Avalanche Centre has been warning that mild temperatures have created heightened risks throughout British Columbia. The centre's latest bulletin for the area put the risk at considerable at lower elevations and high in alpine areas.
"You can only prepare and equip so much and then mother nature will take over," said Thiessen of the RCMP.
"And unfortunately this terrible tragedy, yet again. We have seen it in previous years and hopefully we won't see any more this season, but I'm not confident in that. We have seen many deaths every winter in the backcountry because of avalanches, here."
Eleven people died in snow slides in Western Canada in the 2010-2011 season.
— By James Keller in Vancouver