Avalanche Bulletin
更新日時: 2025/02/24 05:30
Hakuba
Alpine Low Lack of information due to stormy weather
Treeline Fair
Below Treeline Good
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
This is a day to watch out for unstable snow remaining on certain terrains. At higher elevations, instability has not yet fully resolved, so avoid terrain that is prone to triggering (convex or isolated slopes with no underlying support). Also, the mountain is expected to be crowded today. It is important to move and ski safely, using terrain wisely, taking into account your position relative to other groups. Please continue to stop in safe areas and move at appropriate intervals until you reach the base of the mountain. We can expect strong sunshine, so don't forget your sunscreen. Have a good day.
Avalanche Problem
ウインドスラブ Wind slab
Strong winds on the main ridge have also weakened since yesterday afternoon (23rd). Watch for wind slabs, which increase in hardness over time and are difficult to estimate triggering sensitivity. Be alert for isolated terrain. Also, remember that if strong solar radiation enters the area today, the induced sensitivity may increase during the day in areas that are strongly affected by it.
ストームスラブ Storm slab
Be alert for unstable slabs remaining on certain terrains and slopes. Be especially vigilant on steep northeast to southeast facing slopes near the treeline where cross loading snow is deposited by northerly winds.
概要
Avalanche
Yesterday (23rd), a number of size 1-1.5 slab avalanches were reported below treeline. All were caused by ski cuts or other human stimulation. No reports were received at higher elevations due to stormy weather.
Snowpack
The stormy weather that began on February 17 is over. The snowfall, which has been repeatedly strong and weak, has increased the snowpack, but at the same time, there has been a decrease due to settling. This has resulted in a snow depth of 50-70 cm for the stormy weather below treeline. The lower layers of snow that have been in place for a longer period of time are more stable due to sintering and consolidation. On the other hand, there are still elements of instability in the upper layers. Careful judgment is needed because of the lack of information at higher elevations. Particularly on the steep south-facing slopes, there are still concerns about the potential for large avalanches.
Weather
The Japan Meteorological Agency is forecasting northerly winds, cloudy, snowy at times, and a daytime high of 3 °C (418 m elevation) for northern Nagano Prefecture. At Amedas Hakuba (elevation 703 m), the temperature is -9.3 °C (as of 5:00 a.m.), and 1 cm of snow has fallen in the past 12 hours. At the main ridge (elevation 2,400 m), the temperature is -18 °C (as of 5:00) with northerly winds averaging 8 m/s.
