Avalanche Bulletin
更新日時: 2025/03/18 06:30
Myoko
Alpine Fair
Treeline Fair
Below Treeline Fair
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
Even with good weather, this is not a day to relax your avalanche precautions. Assuming that the instability of the previous day's stormy weather continues, avoid large open slopes and start the day on slower, smaller terrain. As you do so, be sure to check the instability within the new snow and the bonding of the new snow with the old snow. Please consider whether there are any "terrain traps" below the slope and choose your slopes carefully. In addition, steep south-facing slopes have the potential for avalanches of significant magnitude if the solar radiation causes the new snow to develop slab tendencies.
Avalanche Problem
ウインドスラブ Wind slab
Extremely strong northwest winds have been blowing since yesterday afternoon. Look for traces of wind slab formation on the snow surface and act accordingly to avoid any hazards. Be alert for steep slopes deposited by cross loading as well as just below the ridge line.
ストームスラブ Storm slab
As the new snow intensifies its slab characteristics due to solar radiation and elevated temperatures, avalanches are more likely to occur in combination with the hard Melt-Freeze crusts in the underlying layers. Be vigilant on steep south-facing slopes.
概要
Avalanche
No information was received yesterday (17th) in the mountain area. In the adjacent Hakuba area, a number of avalanches with storm slabs of size 1-1.5 were reported near the treeline.
Snowpack
The stormy weather that began with the passage of a low pressure system (March 16) appears to have resulted in 40-50 cm of snowfall at higher elevations than in the upper part of the below treeline area. While snowfall observation data in the Myoko area is limited, numerous avalanches and shooting cracks have been reported in the adjacent Hakuba area due to vulnerabilities in the fresh snow. Tenperature gradients have also been reported for bonding with the old snow, the Melt-Freeze crust.
Weather
The Japan Meteorological Agency is forecasting southerly winds, daytime, northerly winds, cloudy, before to after noon, sunny, with a daytime high of 8 °C (13 m elevation) for the Joetsu region of Niigata Prefecture. At Sasagamine, Myoko (elevation 1,310 m), the temperature is -8 °C (as of 4:45 a.m.), with 28 cm of snow having fallen in the past 24 hours.
