Avalanche Bulletin
更新日時: 2025/01/10 06:00
Hakuba
Alpine Fair
Treeline Fair
Below Treeline Good
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
Dangerous conditions with the potential for very large avalanches. This is a day that requires maximum attention to terrain and a large safety margin. Even if you are in the forest, check for large start zones above you. If you ski the forest north of the Toomi-One, the return river route will expose you to avalanches from the large start zone south of the Happo-One. Consider not only the danger of the slopes you will be skiing, but also whether the ski tour as a whole is an acceptable risk to you. For the less experienced, this is a good day to enjoy the fresh snow within the ski resort.
Avalanche Problem
ストームスラブ Storm slab
Not much snow has fallen since last night, but northerly winds have redistributed the snow.
ウインドスラブ Wind slab
Northerly winds are increasing and newly formed wind slabs require caution!
概要
Avalanche
Yesterday (9th), several size 1 loose snow avalanches were observed in very steep terrain below treeline. Higher elevations were not observed due to poor visibility.
Snowpack
The depth of the snowfall, which has been ongoing since January 6, has exceeded 120 cm in the upper part of the below treeline. This new snow is slowly sintering and settling, and is observed to have a generally rightside-up structure (more dense in the lower layers). At times like this, where the snowpack tends to become unstable is on slopes with an upside-down structure formed by dense slabs that have been redistributed by the wind. Since last night, winds have also been increasing, with average wind speeds of 19 m/s and maximum instantaneous wind speeds of 29 m/s recorded on the main ridge.
Weather
The Japan Meteorological Agency is forecasting northerly winds, snow, occasional cloudiness, and a daytime high of 2 °C (418 m elevation) for northern Nagano Prefecture. At 703 m elevation (Hakuba), the temperature is -6.5 °C (as of 5:00), and 7 cm of snow has fallen in the past 24 hours. Strong cold air has arrived, with an average temperature of -12 °C at 1,570 m elevation and -18 °C at 2,450 m elevation. A heavy snow warning is in effect, and the Nagano District Meteorological Office at 5:35 a.m. on the 10th is forecasting 40 cm of snowfall for the Hakuba and Otari areas in the next 24 hours until 6:00 a.m. on the 11th.
