Avalanche Bulletin
更新日時: 2025/02/20 05:30
Hakuba
Alpine Fair
Treeline Low Lack of information on wind effects
Below Treeline Fair
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
Dangerous avalanche conditions continue. Careful terrain observation, careful route setting, and conservative decision-making are required. Move along, making good use of ridges, trees, and other safe zones. Proper spacing with your companions is necessary, and communication can be problematic if there are too many people in your group. Consider smaller groups than usual. Due to the continuing low temperatures, fresh snow is very deep in areas unaffected by wind and solar radiation. Even small avalanches can be deadly if there are "terrain traps" such as terrain depressions or gullies that tend to bury them deep. Even if you are in the woods, pay close attention to the terrain.
Avalanche Problem
ウインドスラブ Wind slab
Wind speeds are slowly decreasing, but there are still northerly winds at higher elevations that are strong enough to move the dry snow. As snowfall continues, we need to consider that there is a large amount of snow available for movement.
ストームスラブ Storm slab
Be alert for large open slopes to the south, even at lower elevations, with buried Melt-Freeze crusts from the February 17 burial.
概要
Avalanche
No new avalanche reports came in yesterday (19th). This is due in part to the stormy weather and the fact that fewer people were entering the field.
Snowpack
Below treeline, the snow from the recent stormy weather that began on February 17 is about 70 cm while continuing to settle and consolidate. At lower elevations, settling is progressing due to yesterday's solar radiation, but with continued low temperatures, the vulnerability within the fresh snow at higher elevations still needs to be given due attention. In addition, continuous northerly winds are blowing and wind slabs are forming where they are affecting the area.
Weather
The Japan Meteorological Agency is forecasting northerly winds, cloudy skies, and in places, snow, with a daytime high of 1 °C (418 m elevation) for northern Nagano Prefecture. At Amedas Hakuba (elevation 703 m), the temperature is -6.3 °C (as of 5:00 a.m.), and 11 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 11 m/s and a maximum instantaneous wind speed of 18 m/s. At 4:15 a.m. on February 20, the Nagano Prefectural Meteorological Office forecast 20 cm of snowfall for northern Nagano Prefecture in the 24-hour period ending at 6:00 a.m. on February 21.
