Fatal avalanche near Mt Cook likely to be triggered by climbers

The avalanche near Mt Cook that killed a person yesterday is likely to have been ruptured by the climbers involved.

Mid-South Canterbury Area Commander Inspector Dave Gaskin said it was difficult to say why the avalanche was set off but it was more than probable the group triggered it while crossing the snow field as the snow conditions were pretty unstable.

Two other people were climbing with the person who died - one had minor injuries and the other was uninjured.

Gaskin said police had no details of the climbers but understood they were reasonably proficient and experienced.

The tragic incident occurred around 1.30pm yesterday on the Eugenie Glacier, just below the Footstool mountain peak.

Gaskin said the climber who was uninjured had stayed behind at the Sefton Bivouac hut because they were sick.

The climber who suffered minor injuries was transported to Twizel for medical treatment.

Police say they hope to be in a position to release a name of the person who died, today.

MetService reports Mt Cook's weather for today was fine spells, with a chance of a shower or two with light winds and a high of 18C.

Gaskin said there was a risk for loose wet avalanches at the time above 12,000m.

"There's various types of snowpack conditions, so loose and wet is as it sounds,' he said.

"It's quite a slushy, icy mixture, that condition can mean that sort of avalanche can run a lot further than a typical slab avalanche which is nicely bound together."

The latest tragedy comes after two mountain guides were killed last month in an avalanche on Mt Hicks that also buried adventurer and philanthropist Jo Morgan.

Jo Morgan is the only survivor of an avalanche that killed her two climbing partners on Mt Hicks last month. Photo / Facebook

Morgan was lucky to escape with her life and told media at the time she was "gobsmacked" to be alive after digging herself out.

Her climbing partners Martin Hess and Wolfgang Maier - who are both originally from Germany but had become New Zealand residents – died.

Morgan had been roped to the two experienced mountain guides when the avalanche hit, but she was unable to find them after being sent tumbling up to 200m down the mountain.

"None of us had any control over it."

Morgan was rescued after setting off a personal locator beacon.

- More to come.