Avalanche Bulletin
更新日時: 2021/12/25 07:00
Niseko Yotei Yoichi Shiribeshi
Alpine Fair アルパインの不安定性は改善していますが、ウインドスラブが特定斜面に残っています。Alpine stability is improving but wind slab is present on leeward slopes.
Treeline Good 荒天の雪の下層はよく沈降し、結合を強めています。しかし、上層部ではまだ雪崩を発生させうる状態です。Storm snow is settling and bonding to the lower pack but slab avalanches are still possible.
Below Treeline Good この標高帯では、乾雪の点発生雪崩が主な注意事項となります。地形の罠を併せ持つ急斜面での滑走は十分な注意が必要です。Loose dry avalanches are the main concern at lower elevations. Use caution skiing or riding steep slopes above terrain traps.
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
Please approach the leeward terrain carefully, as previous windslabs may be hidden under fresh snow. Take good measures against the cold, and be careful about frostbite etc. Merry Christmas! Approach Leeward features with caution as windslab may be buried just beneath the surface of the most recent snowfall. Bring extra warm layers and beware of cold Injuries through this cold snap. Merry Christmas!
Avalanche Problem
点発生乾雪雪崩 Dry Loose snow
とても急な斜面で乾雪の点発生雪崩がありえます。Loose dry avalanches can be expected on steep slopes
ストームスラブ Storm slab
低温はストームスラブをとても軟らかい状態に保っています。Cold temperatures will keep storm slabs very soft.
ウインドスラブ Wind slab
強風に曝されない、稜線より下がった場所にあるウインドスラブに注意してください。Look for windslab on protected features and just below ridge crest.
概要
Avalanche
No the new avalanche have been reported. No avalanche observations have been reported
Snowpack
There has been a 5 -15 cm snowfall in some areas since Friday night. The lower layer of this fresh snow is due to the snow of the previous stormy weather, and is sintered according to the lower layer. Koshimo rough snow has been observed beneath the thawing and freezing crust on December 14, and we are tracking it. This layer is located deep in the snow cover, so it needs significant stimulation to generate an avalanche. The layer below this crust is stable due to the effects of rainfall, etc. 5-15cms of light dry snow fell overnight Friday night in some parts of the zone. This sits on ~1 meter of storm snow that is rounding and bonding to the lower pack. A thin layer of facets has been found in the lower pack below the December 14 Melt/Freeze crust This layer is now buried deep in the pack and would require a heavy trigger to initiate an Avalanche. Below this layer the base is a well consolidated re-frozen rain crust.
Weather
It is forecast that the temperature will drop significantly, and the highest temperature at the foot will drop to -8℃, and the Alpine will drop to -20℃. During the day on Saturday, weak snowfall and moderate southerly winds are forecast, and it is said that wind and snow will intensify at night. The temperature is also low on Sunday, and there is a forecast that weak winds and snowfall will continue until Monday night. Temperatures have dropped significantly with a high of -8C expected in the valley and alpine temperatures as low as -20C. Light snowfall with light to moderate SW wind is expected through the day Saturday with Heavier snow Saturday night. Temperatures will remain cold Sunday with continued light wind and snowfall through until Monday night.
