Light southerly snow on Saturday afternoon may create windslab risk on north-facing slopes.
Beware pockets of stiff new snow on northerly aspects.
Afternoon snow will likely be blown onto firm north-facing slopes and may develop into pockets of wind slab.Watch out for the indicative signs, including snow blowing off ridge lines and changes in the density of snow on slopes lee to the wind-driven snow.
In steep sun-facing terrain it may still be possible to push off a loose wet avalanche if the day warms up.Unlikely doesn't mean impossible. Small doesn't mean inconsequential. Keep you wits about you.
Moderate
A widespread loose wet avalanche cycle has been observed over the last few days, particularly in areas close to the divide.
Park user observations provide important information.
If you see anything, please report it in the public observations section of the NZAA website.
After a thorough rain soaking to ~2200m followed by a good freeze on the night of the 13th, field observations on the 14th confirm that the snowpack is locking up and regaining strength. In most parts of the Park a largely isothermic snowpack is freezing down to a spring structure where concerns exist primarily at surface level. This may not last, but for now it characterises the snowpack. Over the last few weeks winds from all around the compass have stripped higher elevation peaks and ridge lines back to either ice or very firm and now frozen snow. The threshold for avalanches is estimated at around 1500m in the west, tapering east.
Forecast for Saturday 15 August
Some morning cloud about the terrain, otherwise fine. Scattered rain developing in the afternoon, with snow lowering to 500 metres at night.
Wind at 1000 metres
Light, southerly 40 km/h developing late morning, rising to 60 km/h in the evening.
Wind at 2000 metres
Light, southerly 40 km/h developing in the morning, rising to gale 65 km/h developing in the evening.
Freezing level
2100 metres, lowering to 1600 metres in the morning, then to 900 metres in the evening.
Expect areas to be stripped back to hard surfaces from the gale winds at higher elevations. Crampons and an ice axe are a good idea, as many firmer areas now exist.
New Zealand Avalanche Advisory (NZ Mountain Safety Council)
