Aoraki/Mt Cook avalanche a reminder to plan ahead - expert

Aoraki avalanche
The debris was found by a ski touring group yesterday after the avalanche likely occurred earlier this week. Photo credit: RNZ

Back country enthusiasts are reminded to take care in spring after the largest publicly reported avalanche of the year was sighted at Aoraki/Mt Cook.

The size four avalanche was large enough to destroy large buildings or a forest, spreading approximately two kilometres in length and 600 metres across.

The debris was found by a ski touring group yesterday after the avalanche likely occurred earlier this week.

Mountain Safety Council chief executive Mike Daisley said it was a spring-time reminder for back country enthusiasts that the avalanche danger remained.

The avalanche was the largest reported as a public observation via the Avalanche Advisory this year - it's the second largest in terms of the destructive scale.

Typically avalanches of this size would have a mass of about 10,000 tonnes.

Avalanches this size were rarely observed in New Zealand.

"Large avalanches like this are powerful enough to travel far below the snowline in some cases," Daisley said.

"So make sure to check the avalanche forecast at www.avalanche.net.nz and keep avalanche hazard a part of your planning this spring, and for those in Aoraki/Mt Cook all year."

Aoraki/Mt Cook has a year-round avalanche forecast due to the continued risk. There is a current alert for heightened avalanche conditions in high alpine areas with several wet, loose avalanches sighted on steep slopes that are large enough to bury, injure or kill a person.

The Avalanche Advisory has issued warnings for dangerous conditions for high alpine areas in Fiordland over the weekend as a storm is forecast to hit.

Alerts for heightened avalanche conditions are in place for Arthur's Pass, Craigieburn Range, Mt Hutt and Wanaka.

RNZ