Avalanche Bulletin
更新日時: 2025/02/28 05:00
Niseko Yotei Yoichi Shiribeshi
Alpine Fair
Treeline Good
Below Treeline Good Expect a light overnight surface freeze and a rapid rise in temperatures during the day.
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
The rise in temperatures and the freezing level will be the dominant factor for the day. We expect a light overnight freeze, which will break down and become moist early in the day on solar aspects. Expect heavy conditions at lower elevations and look for signs of roller balling in steep terrain to indicate the onset of wet loose activity. Glide avalanches are also a concern and hard to predict, avoidance of spending any time below these features is required today. Pockets of wind slab remain on easterly aspects around ridgeline.
Avalanche Problem
ウインドスラブ Wind slab
Pockets of wind slab can still be found on eastly aspects at higher elevations. Previous westerly winds have created slabs on lee protected slopes near ridgeline and in protected areas.
点発生湿雪雪崩 Wet Loose snow
Lower elevations are expected to lose cohesion in the heat of the day today. The freezing level is expected to rise to 1000 meters combined with clear skies which will result in loose wet activity in steep terrain starting on solar aspects before effecting all aspects.
全層雪崩 Glide slab
A rapid rise in temperature and the possibility of free water moving through the snowpack at lower elevations may result in high consequence glide avalanches today. Avoid spending time below these features.
概要
Avalanche
No new activity has been reported across the region on the 27th. Recently, a natural size one avalanche was observed on an easterly aspect at 950 metres in the Niseko region on the 26th.
Snowpack
On the 26th, snowfall, which was heavier in the south and west combined with westerly winds creating wind slabs on easterly aspects. Windward slopes have been stripped and are firm in exposed areas. At lower elevations a sun crust now lies under the latest new snow with multiple curst found in the upper pack. Fresh cornice formations are brittle.
Weather
A high pressure system over the country today will bring a southerly flow resulting in clear skies, sunshine and the freezing level rising to 1000 meters. Winds will remain light to moderate throughout the day.
