Wednesday looks like a good day to let the dust settle after a pretty windy few days.
Wind slabs formed during this time may still be reactive to light loads.
Evaluate the snow and terrain carefully, avoiding steep, recently loaded features of concern
A few days of gale-force westerly and southerly winds have severely stripped exposed slopes, blown plenty of snow into the atmosphere, and potentially loaded some slopes with wind slabs of various thicknesses that could be reactive in some areas.
Caution is advised on Wednesday where recent loading has occurred.
Most likely above around 1800m on north and east facing slopes.
Nil observed since. Evidence of multiple Sz 2-3 natural storm and wind slab avalanches was observed to have run during the July 30-31st storm. Around the Forbes and Richardson Mountains, these ran on mostly SE aspects between 1900-2100m. Image below shows one on Mt Earnslaw's east aspect.
If you see any recent avalanche occurrences or have any relevant snowpack information or photos, you can share them via the Public Observations link on the NZAA home page.
Up to 50cm of new snow fell between July 30 and 31, and a dusting on the 3rd August. This has since had a good going-over with strong to gale westerly and southerly winds. Exposed slopes, ridgelines and features, mostly west facing, have been stripped back to old layers and rock. Lots of snow has been sublimated off into the atmosphere, large deposits of stiff wind slab formed on lee slopes and large cornices may also be forming along ridgelines above around 1800m.
Before the 30th of July storm the snowpack was still shallow, approximately 60- 70 cm below 1700m and 120cm at 2000m. Crevasses are still very open, and many rock features are still visible, particularly on west-facing aspects.
Although the lower pack appears consolidated, the Aspiring region is very large, and there is still limited data. Caution should still be taken, particularly in steeper, more extreme terrain where unknown weaknesses may exist.
Mt Aspiring National Park ForecastForecast
Fine.
Wind at 1000 metres Light.
Wind at 2000 metres Southerly 30 km/h, dying out before dawn.
Wind at 3000 metres Southerly 30 km/h, dying out in the afternoon.
Freezing level 1400 metres.
Issued: 1:03pm Tue 4 Aug
Exposed areas such as ridgelines on west and south aspects may have been stripped back to old ice layers by recent strong winds. Depending on your objective, an ice axe and crampons could be necessary.
Moderate
New Zealand Avalanche Advisory (NZ Mountain Safety Council)
