Severe gale wind will continue to add to windslabs above about 2000m on Thursday.
Wet loose avalanches are possible at lower elevations.
There is a high uncertainty about the amount of precipitation and the freezing levels for Thursday. It is best to take a cautious approach until the storm is over.
Gale north-west winds will continue to build windslabs on south, south east and east facing slopes.
With a 2000m-2400m freezing level forecast for Thursday, this problem is confined to the highest terrain in the region.
Take care to identify and avoid recent steep windloaded areas.
Rain is expected below about 2000m throughout the range on Wednesday evening.
The lower mountain could have a very weak saturated snowpack that will further weaken with extra heat during the day.
A good overnight freeze, will go a long way toward strengthening the snow.
Take care to observe the state of the snow and be prepared to avoid steep slopes and runouts if the snowpack loses strength.
Multiple small loose wet avalanches were reported in steep terrain in the Camp Stream and Coal river catchments on 13th and 14th. 1800m -2000m NW facing slope.
Current avalanche observations are limited due to the storm.
If you see any activity on the Two Thumb Range, please make a public observation. It really helps us to produce accurate forecasts.
Severe gale NW winds have stripped snow from windward slopes and deposited it onto south, southeast and east facing terrain. Below about 1800-2000m the snowpack has become wet. A freeze overnight on the 14th has formed a widespread crust.
The north of the range continues to receive new snow above about 1800m, with lower snow fall mid range and nothing at the southern end.
Below about 1800m, the precipitation fell as rain.
Snow depths in the south are about 70cm, tapering to about about 50cm mid range and 40cm in the north.
The snowpack north of Stag Saddle is not well understood, with no direct observations.
Showers on Wednesday night clearing to fine.
Wind at 1000 metres
Westerly gale 65 km/h, easing to 35 km/h in the afternoon.
Wind at 2000 metres
Westerly gale 75 km/h, rising to severe gale 95 km/h for a time in the morning, easing to southwesterly 45 km/h in the afternoon.
Freezing level
2000 metres, lifting to 2400 metres in the evening.
The wind has stripped the soft snow back to exposed crusts.
Below 2000m, the snowpack has gone through a melt, so any overnight freeze will form a slick crust.
Sliding danger will be patchy with lots of rocks in the runouts.
Iceaxe and crampons are recommended.
Low
New Zealand Avalanche Advisory (NZ Mountain Safety Council)
