Gale winds and new snow is in the forecast for Friday. The freezing level lowers to 700m, bringing snow to lower elevations.
The avalanche danger remains at Considerable.
Wait for weather conditions to improve before heading out into avalanche terrain.
Wind slab development is likely to continue, with new snow and strong winds on Friday. This is most likely near ridgetop, and around terrain features on aspects facing east through to south.
Natural avalanches are possible, especially at higher elevations.
Observations from Milford Track area, Darran's and Routeburn on 20 July -Slick frozen conditions below 17/1800m. Only the highest peaks (North Peak, Talbot, Mt Christina) had some slopes with enough snow to cover terrain features and look wind loaded.
Estimate about 30 - 45cm of snow above 1700m on 24 July, (with rain below) with strong NW wind
From 21 July - Below around 1800m the thin snowpack had a mixture of rain and snow over the week of 13th to 18th July, culminating in rain up to about 1750m on Saturday the 18th. This snowpack is generally thin, with much of it still below avalanche threshold, and rainsoaked and refrozen.
Above about 1800m there has been about 80 or 90 cm fall in northern Fiordland and about 60cm in the south, from a series of westerly fronts over the week of 13th to 18th July. There were warm temperatures on Saturday 18th and this snowpack is now thought to be stable, with possible remaining wind slab at the high elevation areas lee to the west but should be treated cautiously as there have been not observers in the field.
Rain, heavy at times. Thunderstorms and hail possible until evening. Snow to 800 metres in the morning, lowering to 400 metres towards evening.
Wind at 1000 metres - Northwesterly gale 70 km/h. Turning to southwesterly 50 km/h in the afternoon.
Wind at 2000 metres - Northwesterly severe gale 100 km/h easing to gale 70 km/h in the morning. Turning to southwesterly in the evening.
Freezing level - 1200 metres, lowering to 700 metres in the evening.
Some new snow will change surface conditions. At the moment the snowpack below about 1700 is fast and hard. Take an axe and crampons if you're exploring.
Moderate
New Zealand Avalanche Advisory (NZ Mountain Safety Council)
