A Queenstown man killed in an avalanche at Coronet Peak yesterday afternoon has been named.

Ryan Manu Campbell, 31, died after he was swept up by a category 2.5 avalanche that buried him in over two metres of snow.

He had been snowboarding with two relatives when one of the group triggered the avalanche about 5pm, Coronet Peak ski area manager Hamish McCrostie said.

Rescuers spent two hours digging Mr Campbell out of the snow. He was given medical treatment before being airlifted to Lakes District Hospital where he was pronounced dead.

Mr McCrostie said the group had been snowboarding about 1km from the skifield's boundary in a region called the Dirty Four, near the top of the Greengate chairlift.

Queenstown mountaineering instructor and avalanche expert Chris Prudden told The Press the boarders were in an out-of-bounds area.

"Any time you're on uncontrolled terrain out of bounds you've got to have the equipment, training and knowledge of snow stability. Without that, you're just running the gauntlet and taking a real punt."

Mr Prudden said more than 90 per cent of people caught in an avalanche had triggered it themselves.

"There had just been quite a vigorous snowfall and a lot of wind lately, everything depends on how the new snow is bonded to the old snow. He must have found the tension point or overloaded it by going in there."

Mr Prudden said the man had not had a beacon on him.

"With a beacon, you can be found within minutes. Without one, it's going to be a long time before someone finds you.

"The survival rate falls off very quickly. It goes from 90 per cent chance in the first 15 minutes down to about 10 per cent survival not long after that."

Yesterday's avalanche followed one in the Southern Alps' Rugged Range on July 24, which killed an Australian heli-skier and temporarily buried two others.

Last week, the Mountain Safety Council warned people off skiing across back-country terrain, saying it was at high risk of avalanches big enough to bury a house.

The council noted back-country areas of Queenstown, Wanaka, the Arrowsmiths and the Mt Hutt region as being at particularly high risk.