Lawinenlagebericht

Increase in danger of wet-snow+glide-snow avalanches due to fresh snow, storm winds, high-altitude snowdrifts, intense rain this afternoon

Increase in danger of wet-snow+glide-snow avalanches due to fresh snow, storm winds, high-altitude snowdrifts, intense rain this afternoon

Fresh snow and fresh snowdrifts are prone to triggering, can be triggered even by minimum additional loading. Avalanche prone locations are located in steep terrain in all aspects, behind protruberances, in wind-loaded gullies and bowls. Spread and frequency of danger zones will increase during the course of the day and with ascending altitude. 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. Naturally triggered avalanches likeliest in the afternoon. Due to mild temperatures and intensive rain impact this afternoon, the danger of glide-snow and wet-snow avalanches will increase below 2200 m in all aspects during the course of the day.

During the last 24 hours there has been 10-15 cm of fresh snow above 1600 m. By tomorrow morning, another 10-30 cm will be added to it above 2000-2200 m. The new snow will be intensively transported by strong-to-stormy W/NW winds, large-sized snowdrift accumulations will be generated far distant from ridgelines. New snow and drifts will be deposited on wind crusts or melt-freeze crusts and atop the drifts generated on Tuesday, on high-altitude shady slopes often atop loose and powdery layers which are prone to triggering. At intermediate altitudes and on south-facing slopes, bonding to the old snowpack surface is better. Furthermore, on high-altitude very steep shady slopes there are often weak layers at mid-level inside the snowpack or older drifts which are trigger-sensitive. At low and intermediate altitudes the snowpack has been further weakened by higher temperatures and rain influence. As of afternoon, rainfall up to 2200 m will make the snowpack thoroughly wet.

Dry this morning, but clouds will not disperse much. Starting at midday cloud cover will become dense, increasing fog, and gradually heavy precipitation will set in. Rainfall will extend up to 2000 m, snowfall in high alpine regions. Temperature at 2000 m: rising from -3 to +3 degrees. Strong to stormy westerly winds at high altitude, later shifting to northwesterly.

As a result of a warm front the snowfall level will ascend to 2500 m on Wednesday night, so large amounts of fresh snow are only to be expected at high altitudes. The avalanche situation will remain tense.