Wind slabs are present on north and west aspects. Loose wet avalanche hazard may develop as cooling winds back off and solar radiation impacts the surface snow. The weather remains settled over the next 24 hours with clear skies and light winds. Good visibility and fine conditions suit alpine backcountry travel.
Wind slabs exist. South-southeast winds ramped up, becoming gale at times over the previous 24 hours. This has redistributed any loose snow onto north and west aspects. Wind-driven deposits have formed around terrain features acting as catchments. These deposits are high in the paths and stubborn. Loaded start zones lacking support will be areas of concern.
Loose wet avalanche activity is possible on solar aspects. Any evenly distributed snow will react in a negative way once impacted by direct sun. Loose wet activity will be specific to steep sun-affected slopes. The warmest period of the day will be the height for activity. Cooling south winds may limit surface breakdown at some locations. Watch for point release activity and roller ball near and under cliffs and rock bands.
Cornice formation has occurred. Formations will be isolated to south- and east-facing ridgelines. Cornices will be reactive to light loads, as most lack any decent support. Failure will remain a possibility. Triggering a localised wind slab will be possible. Recommend avoidance and maintaining a decent distance even after the storm event.
No human- or natural-triggered avalanche activity has been reported or observed over the past 24 hours.
A minimal amount of loose snow is currently being transported to north- and east-facing aspects. Low-volume slabs are forming but are resistant to light loads. Light winds in the northwest areas with clear skies are prime conditions for surface breakdown. On average, the last storm cycle brought half a metre of new snow to the region at an elevation of 2000 metres. The older, deeper snowpack is consolidated and supportive. No step-down into the older snowpack was observed during testing over the past few days. Snow cover exists on Mt Ngauruhoe and Mt Tongariro. If doing the Tongariro crossing, you will be traveling over snow and ice. Alpine gear and precautions need to be considered. The south-west areas have enough snow cover in start zones above 1600 metres for avalanches to run freely (threshold). In the northern areas, the threshold is at a slightly higher elevation, but this is also changing fast. This recent snowfall has improved snow cover overall and lowered the threshold in the northern areas and east (about 1600 metres elevation). Check photo of the start zone and snow cover at Turoa (photo taken am 28072026), at 1750 metres, with a north-west aspect.
Tomorrow, the 29th of July, will remain settled with fine, clear conditions. The winds will be moderate southerly, tending west / northwest and easing overnight into Wednesday. The freezing level is 2000 metres, lowering to 1200 metres for a time in the morning. A ridge of high pressure over the country moves slowly eastwards tomorrow as a front approaches from the Tasman Sea; meanwhile, a northwest flow builds over the South Island.
Slick rime crusts are present, posing a sliding hazard. Moderate winds are stripping any loose snow, exposing these crusts on ridgelines and windward terrain features. Numerous hazards, such as exposed rocks and cliff bands, remain. Carrying an ice axe and crampons is recommended in the backcountry. It is essential to have strong alpine skills and competence when travelling over slick surfaces with high consequences.
High
New Zealand Avalanche Advisory (NZ Mountain Safety Council)
