Avalanche Bulletin
更新日時: 2025/01/16 06:00
Myoko
Alpine Fair
Treeline Low Degree of wind impact unknown.
Below Treeline
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
Hazardous conditions associated with yesterday's strong daytime snowfall are dissipating, but there are still conditions that require extreme caution. Entering large open slopes, even below treeline, is not recommended. Especially on steep south-facing slopes, Melt-Freeze crusts are buried under new snow and have the potential to create large avalanches. The best means of lowering avalanche risk is to choose gentle slopes. However, the large amount of new snow prevents speed. As a result, we tend to head for steep slopes that are ideal for avalanches. Today, as yesterday, is a good day to enjoy powder snow in the ski area. When enjoying new snow areas, use the "buddy system" of skiing with a friend. Some accidents have occurred where people have been buried in deep snow and suffocated, not avalanches.
Avalanche Problem
ストームスラブ Storm slab
Yesterday, a large amount of snow with low cohesion resulted in numerous avalanches of very soft slabs. Today, the snow that made up those soft slabs is sintering and making up more solid slabs. This makes larger avalanches more likely to occur.
ウインドスラブ Wind slab
Extremely strong northwest to north winds were blowing at higher elevations until late yesterday night. A large amount of new snow has been moved downwind by this wind, forming wind slabs. The high density of slabs on top of the less cohesive snow has resulted in the appearance of many areas of inverse structure, which is typical of unstable snowpack.
概要
Avalanche
Yesterday (15th), a number of avalanches and shooting cracks on size 1-1.5 storm slabs were reported during morning safety operations at the ski resort. Due to stormy weather, no information has been received for the Myoko mountain area.
Snowpack
Yesterday, a strong snowfall occurred and the snowpack quickly became unstable. This time, the new snow is about 70 cm below treeline (1,300 m elevation). The stabilization of the new snow is expected to be slower due to the cooler temperatures than yesterday. Also, in Alpine, it was blowing from noon to midnight yesterday. Therefore, although the snowfall itself has subsided somewhat, one must consider that a large amount of new snow is being moved by the wind and forming slabs.
Weather
The winter pressure pattern will gradually loosen, but a cold front extending from a low-pressure system moving over the Sea of Japan is expected to approach during the night. The Japan Meteorological Agency is forecasting northwesterly and westerly winds, with snow or rain, cloudy from early afternoon, and daytime high temperatures of 5 °C (13 m above sea level) for the Joetsu region of Niigata Prefecture. At Sasagamine, Myoko (elevation 1,310 m), the temperature is -8 °C (as of 5:45 a.m.), with 33 cm of snow having fallen in the past 12 hours and 62 cm in the past 24 hours.
