Avalanche Bulletin
更新日時: 2025/02/12 07:00
Niseko Yotei Yoichi Shiribeshi
Alpine Fair Hazard will increase as winds intensify and temperatures rise.
Treeline Good Hazard will increase as winds intensify and temperatures rise.
Below Treeline Good Hazard will increase as winds intensify and temperatures rise.
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
Monitor the rapid rise in temperature and changing avalanche conditions as you travel today. A heavy storm is approaching this afternoon so be prepared to finish early if the system arrives sooner than expected.
Avalanche Problem
ウインドスラブ Wind slab
Moderate SW winds will re-distribute storm snow and form slabs on leeward slopes.
ストームスラブ Storm slab
A rapid rise in temperature today will cause the storm snow to form into a slab. The slab is more likely to be reactive or solar aspects where the storm snow overlies the Feb. 8th melt/freeze crust.
点発生乾雪雪崩 Dry Loose snow
Loose dry avalanches are expected in steep terrain today.
概要
Avalanche
Loose dry avalanches were reported in steep terrain yesterday but no slab avalanches have been reported.
Snowpack
5cms of new snow overnight brings the storm snow total to 20-50cms with amounts varying across the region. The storm snow overlies a thin melt freeze crust on solar aspects that formed on Feb. 8th and adds to approximately 1 meter of settled snow on polar aspects. The Jan. 28th PWL still exists and is now buried 1-2 meters deep; however recent tests indicate that it stubborn and unreactive. There has also not been any avalanches reported on this layer in the past week so the persistent slab problem has been removed however the layer will continue to be monitored.
Weather
A SW flow has taken over as a low pressure system develops to the SE of Hokkaido. Snow showers in the morning will become more consistent in the afternoon before heavy snow starts in the late afternoon / evening. 5-10cms of new snow is expected through the day accompanied by moderate SW winds. There is the chance of the occasional sunny break in the morning before the storm arrives in the afternoon. The SW flow alls brings warmer air with freezing levels rising to 350m with a high of +3C in the valley today. This afternoon`s storm will start with moist snow at lower elevations.
