Lawinenlagebericht

Fresh snowdrift accumulations and weak layers at high altitude. Wet-snow, glide-snow avalanches at intermediatae altitudes due to rain+warmth.

Fresh snowdrift accumulations and weak layers at high altitude. Wet-snow, glide-snow avalanches at intermediatae altitudes due to rain+warmth.

The freshly generated snowdrift accumulations above 1800 m are prone to triggering and can be released even by minimum loading and grow to medium size. Spread and frequency of danger zones increase with ascending altitude. Due to new snow and winds, they continue to spread and deepen. On high altitude very steep shady slopes and in extremely steep terrain isolated small-sized slab avalanches can be triggered by large additional loading in transition zones from shallow to deep snow, e.g. at entries into gullies and bowls or in spots where the snow is shallow. Particularly on steep grass-covered slopes and hillsides which have not yet discharged, small-to-medium glide-snow avalanches are possible. Cracks in the snowpack surface are red flags. Due to rainfall and higher temperatures, the danger of wet-snow avalanches increases below 1800 m during the daytime.

Yesterday foehn wind was blowing in exposed terrain at moderate to strong velocity as of midday, in gusts reaching strong to very strong velocity and thus transporting the loose snow. During the night there was 5-10 cm of new snow registered (snowfall level 1200-1500m). During the day an additional 15-20 cm will be added to it above 1700 m. This will be transported by strong-to-stormy westerly winds. The new snow and snowdrifts sill be deposited on top of wind crusts or melt-freeze crusts, sometimes at high altitudes atop still loose, powdery snow or layers which are blanketed with surface hoar and thus, prone to triggering. At intermediate altitudes and on south-facing slopes, bonding to the old snowpack is better. Furthermore, on high-altitude very steep shady slopes there are weak layers at mid-level in the snowpack in some places which are prone to triggering, as are some older snowdrift accumulations. At low and intermediate altitudes the snowpack has been weakened by mild temperatures and minor rain impact. Last night a breakable melt-freeze crust formed which will soften during the day.

The mountains will soon be covered in clouds coming from the west, visibility will deteriorate, accompanied by a few windows of sunshine. Light rainfall will come in repeated bouts during the day, above 1700 m as snowfall. Very windy in ridgeline zones. Temperature at 2000 m: -3 to +1 degree. Strong to stormy westerly winds.

Between Wednesday and Thursday, lots of rainfall extending up to high altitudes is expected. Winds will be blowing at strong-to-storm strength from W/NW directions, transporting the new snow at high altitude. Danger of wet-snow and dry-snow avalanches could increase strikingly.