Avalanche Bulletin
更新日時: 2024/03/18 05:30
Hakuba
Alpine Low Snowfall amount unknown
Treeline Low Snowfall amount unknown
Below Treeline Fair
信頼度：○ good □ Fair △ Low
Travel and Terrain Advice
At higher elevations, watch out for slabs that have formed from the snowfall since last night. Uncertainty is high because the amount of snowfall is unknown, but since very strong winds are blowing on the main ridge, it is necessary to assume that the amount of snow is at least enough to form slabs to shed people. Also, due to yesterday's high temperatures and rainfall, the snow surface is hard and frozen in some areas. Be careful of slips and falls. Melting of snow at lower elevations is underway. Careful tour planning and conservative route selection on site are required.
Avalanche Problem
ストームスラブ Storm slab
Very strong northwest winds, averaging 20 m/s, are blowing on the main ridge. Be alert for slab formation on the downwind side.
持続型スラブ Persistent slab
The danger of persistent slabs from ice layers or Melt-Freeze crusts formed by the February 21 rainfall and faceted snow that formed on top of them remains highly uncertain.
概要
Avalanche
Numerous snowballs were observed yesterday (17th) associated with rising temperatures and rainfall.
Snowpack
Yesterday (17th), 12°C was recorded at the foot of the mountain before noon, and positive temperatures were also recorded near the treeline. There was also some light rainfall, which wet the upper snowpack layer, and snowballs were observed. Then, last night, the pressure pattern changed to a winter pressure pattern, and cold air is flowing in. The snowpack at lower elevations is in a spring cycle of repeated Melt-Freeze and Freeze. At higher elevations, we need to keep an eye on the snowfall from last night.
Weather
The Japan Meteorological Agency is forecasting northerly winds, cloudy, sometimes sunny, snowy in places, and a daytime high of 6 °C for northern Nagano Prefecture. At 703 m elevation (Hakuba), the temperature is -0.3 °C (as of 5:00 a.m.), and no new snow has fallen in the past 12 hours. The Nagano District Meteorological Office, at 4:51 a.m. on March 18, is forecasting 15 cm of snowfall for northern Nagano Prefecture in the 24-hour period ending at 6:00 a.m. on March 19.
