The New Zealand Avalanche Advisory (NZAA) is warning of very dangerous avalanche conditions for Tongariro.
The level 4 (high risk) alert is in place for high alpine areas (above 2300 metres), while a considerable danger warning has been issued for alpine terrain elevations (1800m - 2300m).
The advisory said multiple avalanches, mostly small, had been triggered by explosive testing at Whakapapa.
The New Zealand Avalanche Danger Scale, which runs from 1 (low risk) to 5 (extreme risk), shows that under a level 4 alert natural avalanches are likely and human-triggered avalanches are very likely.
At level 3 - considerable risk - natural avalanches are possible and human-triggered avalanches are likely.
NZAA said the avalanche problem at Tongariro was primarily located in the southern areas of the region, around Turoa.
The advisory, which is owned and managed by the New Zealand Mountain Safety Council (MSC) provides avalanche forecasts for 13 locations across New Zealand during the relevant avalanche seasons.
NZAA has also issued a considerable risk (level 3) alert for Taranaki at elevations above 1200m.
It said areas of wind slab existed above 1600m on north to northeast aspects and there was potential for new snow instabilities to have developed with the changing wind speed and weather conditions.
