The Mountain Safety Council says only luck prevented an avalanche tragedy on Ruapehu yesterday.
A spokesman said they were "very close" to experiencing the mountain's worst disaster after rapid warming caused three large avalanches to release above the Turoa ski area.
Andrew Hobman said several skiers and snowboarders walked past the avalanche advisory sign warning people of the danger.
"It was on 'Considerable' which means there is a considerable likelihood of avalanches and it is recommended that only people with expert avalanche skills should travel in the backcountry,' Hobman said.
"People need to be aware that as soon as they step outside the ski area boundary, that they are on their own and need to manage their own risk and make travel decisions accordingly."
The council has praised the ski area's response to the event. Hobman said they knew there were people in the region of the slides and reacted very quickly to search the area, locate the groups and get them safely back into the ski area.
Most avalanches are caused by the victim or someone in the victim's party and in this instance Hobman said the group triggered another avalanche that could have killed many of them.
"By sheer luck, the avalanche process started but did not fully release. We were very close to a huge tragedy."
No one was injured in the snow slides and the upper half of the ski field was closed for the rest of the day.