New Zealand Avalanche Advisory forecasters are warning back-country users in the Southern Lakes not to underestimate the "spooky" snowpack conditions.
Back-country users in Queenstown and Wānaka were triggering avalanches daily — something which was not normal — due to what Queenstown avalanche forecasters Chris Cochrane and Will Rowntree described as a "persistent weak layer".
"The snowpack is getting weaker, not stronger, so we ask users for a conservative approach when planning a trip into the back country," Mr Cochrane said.
On Wednesday two back-country skiers triggered a large (size 2.5) avalanche behind The Remarkables ski area.
The 250m-wide avalanche carried one skier, who lost gear, but was uninjured.
Then on Thursday another two large avalanches were triggered by back-country users.
Last Saturday two under-prepared Wānaka climbers were the subject of a 14-hour rescue mission after triggering a small avalanche on the south face of The Remarkables, disoriented in blizzard conditions.
While these events ended without tragedy, they were a timely reminder the current conditions required a high degree of caution and vigilance, Mr Cochrane said.
Mr Cochrane said it was also a good reminder for ice climbers and mountaineers, because triggering even a small pocket of wind-slab avalanche could result in a fall in difficult terrain.
NZ Mountain Safety Council chief executive Mike Daisley said in the past week alone there had been a hive of activity around the Southern Lakes, especially out of bounds from The Remarkables ski area.
"If you’re thinking of heading out of the ski area boundary, it’s essential you are prepared for the back country.
"That means making sure you have checked the avalanche advisory and understand it.
"Ensure you have avalanche rescue equipment and you know how to use it.
"Go with a buddy, and the right mindset. Be mentally prepared to assess the conditions and be prepared to turn back."
Mr Daisley said during the early winter season, data and observations could be scarce and he encouraged people to submit public observations via the advisory’s website, to share knowledge and any activity in the mountains.
"Ski areas and heli-ski operators have only recently started up for the season and with a slow start to the snow arriving we’re still in quite a low-data period."
Forecasters update the 13 regional forecasts at avalanche.net.nz daily, or as conditions change and new information became available.
