<< ニセコなだれ情報 第90号 Niseko Avalanche Info No.90 | main | ニセコなだれ情報 第92号 Niseko Avalanche Info No.92 >>
ニセコなだれ情報 第91号 Niseko Avalanche Info No.91

山麓-8度降雪わずか、モイワ800m-10.1度西8.6m/s未明17m/s雪庇発達降雪わずか、アンヌプリ1150m-14度北西15m/s風雪視界不良降雪わずか、ヒラフ山頂-13度風雪視界不良降雪わずか、日本海弁慶岬北9m/s、神威岬西北西7m/s気圧1020hPa波高1.5m、

 

気圧の傾きやや強く未明にかけて西寄りの強風、雪の量は少ないが飛雪で発達した雪庇は崩壊しやすい。見返りボウルでは過去に同じ状況で地元の中学生3名が雪庇崩壊による雪崩に埋められる事故が起こっている。標高800m以上の雪庇斜面では注意。雪崩は雪の量にかかわらず条件がそろえば起こりそこに人がいれば事故になる。

 

全体の雪崩リスクは低い。各山頂ゲートは開けられる見込み。パトロールの判断に従うこと。全層雪崩の事故を避けるため谷底を滑る習慣を改めるべき。標高差の大きな急斜面が続くアンヌプリ南東斜面の全層雪崩は時に地形や植生に大きな影響を与える。同様の雪崩は過去に見返り林道付近でも起こっている。今冬の降雪推移から春は厳重な注意が必要。季節は寒暖を繰り返して春に移行している。良い一日を。 

 

Niseko base 6.00am: -8°, trace new snow. Moiwa 800m: -10.1°, W8.6m/s(overnight 17m/s), trace new snow, cornice development. Annupuri 1150m: -14°, NW15m/s snow wind, trace new snow, poor visibility. Hirafu peak: -13°, snow wind, trace new snow, poor visibility. Coastal data: Benkei Cape: N9m/s. Kamui Cape: WNW7m/s, 1020hPa, wave 1.5m.

 

The barometric pressure gradient has steepened and a strong westerly wind blew overnight. Only a small amount of snow has fallen however new cornice development from wind blown snow is collapsing easily. In the past in similar conditions 3 high school students were buried by an avalanche caused by a cornice collapsing in Mikaeri Bowl. Take care on cornice slopes above 800m. An avalanche happens when conditions are right regardless of the amount of snow and only becomes an accident if people are involved.

 

Overall the general avalanche risk is low. Peak gates are expected to be open. Follow the patrol's decisions. To avoid getting caught in a full depth avalanche you should reconsider your habit of riding in the valley bottoms. On the south east side of Annupuri where there are steep slopes with large elevation changes, full depth avalanches can have a major impact on the topography and vegetation. Large avalanches like these have come down onto the forest road in the past. From the snowfall this winter strict precautions are needed for spring. Spring is here now with these freeze/thaw cycles. Have a good day.

| - | 07:45 | - | - | pookmark |