The New Zealand Mountain Safety Council (MSC) has posted a video of Saturday’s event on social media, showing the "very serious, potentially life-threatening avalanche".
MSC chief executive Mike Daisley said it was one of two avalanches recorded in the Wānaka area at the weekend, and he was now urging backcountry skiers, snowboarders and climbers to be "extremely cautious" and follow advice provided by the NZ Avalanche Advisory (NZAA).
He said the incident was a sobering reminder that avalanche danger was very real.
"While details are still limited at this early stage, both avalanches occurred in backcountry terrain outside the ski area boundary.
"Given the current conditions, travel in avalanche terrain is not recommended in this area."
The NZ Avalanche Advisory showed avalanche danger was "high" in the Wānaka and Queenstown region, following recent spring snowfalls combined with high winds and poor snowpack stability.
"High danger means very dangerous avalanche conditions exist," he said.
"Natural avalanches are likely, and human-triggered avalanches are very likely.
"At this danger rating, the alpine backcountry is not a sensible place to be."
Fortunately, all four skiers were reported safe and sound, and only one of the skiers received minor injuries.
A police spokeswoman said emergency services were alerted to the avalanche about 2.30pm.
Police Search and Rescue and an avalanche response team were advised, but neither attended because all four people were accounted for and safe.
Mr Daisley said anyone entering the backcountry must have the necessary training, skills and equipment to manage avalanche risk.
"It’s vital that backcountry users follow the travel advice in the NZ Avalanche Advisory and adjust their plans accordingly.
"That means avoiding avalanche terrain when the danger is elevated, recognising signs of instability and always carrying the essential rescue gear — a beacon, shovel and probe.
"Preparation and informed decisions save lives," he said.
