Avalanche Bulletin
更新日時: 2024/12/18 07:00
Niseko Yotei Yoichi Shiribeshi
Alpine Fair Limited observations reduce our confidence in the hazard rating.
Treeline Fair Limited observations reduce our confidence in the hazard rating.
Below Treeline Fair Slab development will be dependent on the amount of day time warming and length of the sunny breaks. Hazard may vary across the region due to these factors
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
Today`s break in the storm will provide the opportunity to travel higher into the mountains, however there is a significant amount of new snow that requires time to bond. Avoid large open slopes and evaluate conditions carefully as you ascend. Pay particular attention if the sun does come out, as this will activate the storm slab. Early season hazards and deep snow immersion continue to be a significant concern particularly at lower elevations.
Avalanche Problem
ストームスラブ Storm slab
Sunny breaks and daytime warming will activate the storm slab
ウインドスラブ Wind slab
Windslab formed during the storm and may be reactive in specific terrain features lee to the WNW winds
点発生乾雪雪崩 Dry Loose snow
Overnight snow arrived very light, dry and without significant wind. Loose dry avalanches can be expected on steep slopes particularly in the Niseko range which has received more recent snow than other areas.
概要
Avalanche
No new avalanches observed.
Snowpack
New snow amounts varied greatly over the past 24 hours with 30-40cms in the Niseko range but 5-15cms in the North and East (Yoichi and Shiribetsu areas) parts of the zone. This new snow overlies a consolidating early season snowpack which steadily increases in density from the surface down to a deteriorating crust at the sassa / ground interface. Tests on a SW aspect of Shiribetsu produced a hard propagating result down 45cm on a layer of preserved precipation particles.
Weather
Snow and winds are expected to taper off this morning with a chance of the occasional sunny break particularly in open areas of the valley. With the clearing skis, valley temperatures are expected to rise to -3C however temperatures higher on the mountain will remain cool as long as they are not exposed to the sun.
