Avalanche Bulletin
更新日時: 2025/03/26 05:30
Hakuba
Alpine Fair
Treeline Fair
Below Treeline Fair
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
It is a very warm morning. Temperatures have been on par with the high observed yesterday at the foot of the mountain from dawn until now. During the daytime, the upper layers of snow are melting and losing their bonding strength due to the added effect of solar radiation. Because of the high temperatures, meltwater is also occurring and there is a risk of glide avalanches. Even below treeline, please increase your terrain awareness and be on the lookout for steep gullies in the forest.
Avalanche Problem
全層雪崩 Glide slab
Avoid slopes with glide cracks. Be alert for collapsing snow blocks that remain in cliff-like areas.
点発生湿雪雪崩 Wet Loose snow
On large steep slopes, snow will gather and increase in size. Do not be caught off guard by the small amount of snow that has started to move.
概要
Avalanche
A number of size 1 wet loose snow avalanches were reported yesterday (25th) in the treeline and below treeline. The triggers were caused by ski cuts and riding stimuli. A size 2 glide avalanche was reported below treeline. In addition, a Japanese serow was reported to be swept away by a wet loose snow avalanche below treeline. The serow escaped and survived.
Snowpack
Yesterday, snow below 2,200 m elevation lost strength as it became moist or wet, regardless of slope aspect. Today, since very warm air has been coming in from the southwest since early morning, snow conditions should be considered poor from the morning.
Weather
Extremely high temperatures have been reported since early morning due to warm air moving toward a low pressure system passing over the northeastern part of Japan. The Japan Meteorological Agency is forecasting a southerly wind, later northerly wind, clear skies, and a daytime maximum temperature of 19 °C (418 m elevation) for northern Nagano Prefecture. At AMeDAS Hakuba (elevation 703 m), the temperature is 14.5 °C (as of 5:00 pm) and there has been 1 mm of precipitation in the past 24 hours. At the main ridge (elevation 2,400 m), the temperature is -1 °C (as of 5:00) with winds averaging 13 m/s and a maximum of 27 m/s instantaneously.
