Avalanche Bulletin
更新日時: 2025/03/17 05:30
Hakuba
Alpine Fair
Treeline Fair
Below Treeline Fair
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
Dangerous avalanche conditions. Hard crusts under fresh snow can be easily triggered, and even small avalanches can cause you to slip and fall if you lose your footing. Careful route setting and conservative decision-making are necessary. Also, consider the possibility that a previous rough, bumpy, hard snow surface may be hidden beneath the fresh snow. At lower elevations, glide avalanche hazards continue due to the previous day's rainfall. Stay away from slopes with glide cracks.
Avalanche Problem
ストームスラブ Storm slab
There is a very hard Melt-Freeze crust under the new snow. Carefully check the bonding between the new snow and the old snow.
全層雪崩 Glide slab
Glide avalanche danger continues at lower elevations where rainfall occurred yesterday. Watch for collapsing unstable snow blocks that remain on cliff-like and other extreme terrain.
概要
Avalanche
Yesterday (16th), several size 1 slab avalanches were observed below treeline. All were human-triggered by ski cuts. Due to poor weather conditions, no information has been received at higher elevations.
Snowpack
Yesterday (16th), as of the morning, it was weak snowfall associated with the passage of a low pressure system, but later changed to rain around noon. The freezing level is generally around 1,300 m. At higher elevations, 20-30 cm of snow has fallen since yesterday. Initially, it was falling with southwesterly winds, but has since shifted to the north with the transition to a winter pressure pattern. There is a very hard Melt-Freeze crust under this new snow, so it is necessary to check the bonding of this crust. Also, at lower elevations, there is a large amount of thawing water within the snowpack due to rainfall, so consider that the risk of glide avalanches continues to be high.
Weather
The Japan Meteorological Agency is forecasting southerly winds, later northerly winds, cloudy, with occasional snow or rain, and a daytime high of 7 °C (418 m elevation) for northern Nagano Prefecture. At AMeDAS Hakuba (elevation 703 m), the temperature is 0.7 °C (as of 5:00 a.m.), with 18 mm of precipitation in the past 24 hours. At the main ridge (elevation 2,400 m), the temperature is -10 °C (as of 5:00), with northerly winds averaging 15 m/s and a maximum instantaneous wind speed of about 18 m/s.
