Avalanche Bulletin
更新日時: 2025/01/01 07:00
Myoko
Alpine Fair
Treeline Fair
Below Treeline Fair
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
Even as the weather improves, the instability of the snowpack will not dissipate anytime soon. Be especially wary of large steep slopes opening to the south today. The bulk of the snow from yesterday is on top of crusts that formed on the 30th, and the snow is being redistributed and heavily loaded by stronger westerly to northerly winds. Even if there are trees around you, consider whether there are any large start zones above you. Please use conservative route setting and a principled course of action while looking for where the wind-driven snow has shifted.
Avalanche Problem
ウインドスラブ Wind slab
Extremely strong northerly winds in excess of 25 m/s are blowing in Alpine. This is a day to be very careful not only for simple downwind, but also for wind slabs that will form around the terrain and on the sides of the branch ridges.
ストームスラブ Storm slab
Be alert for steep slopes with crusts formed by solar radiation.
概要
Avalanche
Yesterday (31st), glide avalanches and block collapses were reported at very low elevations. No reports were received at higher elevations. On the other hand, several storm slab and wind slab avalanches were reported in nearby Hakuba.
Snowpack
The crust formed by the sunny weather of the 30th is on a steep slope that is affected by solar radiation, and the snow from this storm is on top of it. As of yesterday, it was reported that the bonding conditions on this boundary surface were not good. Most of the avalanches reported in the Hakuba area are of this type. And in the middle layer of snow accumulation, there is snow from the stormy weather that lasted from the 26th to the 29th, but is gaining strength. At very low elevations, it is reported that in some places the high temperatures have not stopped the movement of glide cracks.
Weather
The winter pressure pattern is expected to loosen in the afternoon, but cold air and a pressure trough are still expected. The Japan Meteorological Agency is forecasting westerly winds, slightly strong, snow or rain, cloudy from midday, and daytime high temperatures of 7 °C (13 m elevation) for the Joetsu region of Niigata Prefecture. At Sasagamine, Myoko (elevation 1,310 m), the temperature is -7 °C (as of 5:45 a.m.), and 20 cm of snow has fallen in the past 12 hours and 44 cm in the past 24 hours.
