Beware fresh snow, drifts and weak layers on shady slopes: prone to triggering
The fresh snow and drifts can trigger medium-sized avalanches even by minimum additional loading. Danger zones occur primarily in steep terrain and in wind-loaded gullies and bowls. Frequency and spread of avalanche prone locations increase with ascending altitude and during the course of the day. If avalanches on high-altitude shady slopes fracture down to deeper weak layers, they can in isolated cases then grow to large size. Such avalanche prone locations occur primarily in spots where the snow is shallow or in transitions from shallow to deep snow. Particularly if there is solar radiation, small-to-medium sized avalanches are possible in steep rocky terrain.
Snowpack
From Saturday until Sunday morning there was about 20cm of fresh snow registered in the Arlberg region, up to 25cm in Rätikon, Verwall and the Silvretta. As a result of brisk westerly winds, later on blowing at strong velocity, fresh snowdrift accumulations will be generated. These will be deposited on top of a loosely-pack layer and are prone to triggering. The mid-level part of the snowpack consists of well-settled, compact layers widespread which on high-altitude shady slopes cover a poorly structured old snowpack fundament.
Tendency
Avalanche danger will slowly diminish overall, however, intermittent N-NW winds will generate new snowdrift accumulations which will be prone to triggering. With solar radiation, the danger of wet-snow avalanches will increase over the course of each day.
Danger level
1800m
Avalanche Problem
Wind slab
1800m
Wind slab
1800m
Beware snowdrifts: prone to triggering
The fresh snow and drifts can trigger medium-sized avalanches even by minimum additional loading. Danger zones occur primarily in steep terrain and in wind-loaded gullies and bowls. Frequency and spread of avalanche prone locations increase with ascending altitude and during the course of the day. If avalanches on high-altitude shady slopes fracture down to deeper weak layers, they can in isolated cases then grow to larger size. Particularly if there is solar radiation, small-to-medium sized avalanches are possible in steep rocky terrain.
Snowpack
From Saturday until Sunday morning there was about 20-30cm of fresh snow registered. As a result of brisk westerly winds, later on blowing at strong velocity, fresh snowdrift accumulations will be generated. These will be deposited on top of a loosely-pack layer and are prone to triggering. The mid-level part of the snowpack consists of well-settled, compact layers widespread which on high-altitude shady slopes cover a poorly structured old snowpack fundament.
Tendency
Avalanche danger will slowly diminish overall, however, intermittent N-NW winds will generate new snowdrift accumulations which will be prone to triggering. With solar radiation, the danger of wet-snow avalanches will increase over the course of each day.
Danger level
1800m
Avalanche Problem
New snow
1800m
Persistent weak layer
1800m
Wind slab
1800m
Wet snow
1600m
New fallen snow, weak layers still deep in the snowpack
Since Saturday, 10-20 cm of New fallen snow has fallen above altitudes of around 1600 m. It snowed with a moderate south-westerly wind, which built up small snowdrift accumulations on the leeward sides. In addition to the new fallen snow, weak layers in the snowpack deeper in the snowpack are a problem. These weak layers are more numerous in the axis above the forest. In particular, a large avalanche can be triggered if the load exceeds the load-bearing capacity of these layers.
Precipitation will occur in the second half of the day on Monday. The snowfall level will be at an altitude of around 1500 m and 20-30 cm of New fallen snow is expected to fall. The danger of avalanches will increase due to new fallen snow in the high alpine regions. Initially, it will rain in the mid-mountains. The rain will stabilise the snowpack and wet snow avalanches may occur.
Snowpack
dp.1: deep persistent weak layer
In an old snow cover, the layers of snow are mostly well connected, with a Crust on top that mostly supports the skier's weight. Deep below the surface, there are several weak layers of shreds and sheared grains.
Since Saturday, 10-20 cm of new fallen snow has fallen on top of the old snow cover above altitudes of about 1600 m. During the snowfall, some localised freshet may also have fallen, which represents a new Weak layer. On Monday, a further 20-30 cm of New fallen snow is expected to fall in the second half of the day.
Tendency
The danger of avalanches will remain the same.
Danger level
treeline
Avalanche Problem
Wind slab
Treeline
Persistent weak layer
2000m
Prone to triggering wind slab during the daytime changes.
The avalanche risk is moderate above the tree line and low below. Fresh wind slab is the main problem. Slab avalanches can be triggered in places with a small additional load. This is possible above all in steep terrain adjacent to ridgelines in the north, east and south aspects as well as in gullies and bowls. The number of avalanche prone locations increases during the day changes.
On shady slopes at high altitudes, avalanches can break through to deeper layers in the persistent weak layer and reach medium size.
With sunlight, the new fallen snow detaches itself from the rocky steep terrain as small loose snow avalanches and slides down on the crusted old snowpack.
Snowpack
Fresh snowdrift accumulations form with winds from north-westerly directions. Some of these come to rest on a soft layer of snow and can be prone to triggering. In shady high altitudes, layers of faceted crystals can be found deep in the otherwise compact old snowpack. At medium altitudes, the snowpack is wet towards the ground.
Tendency
Depending on the amount of new snow, the avalanche risk may increase slightly.
Danger level
2000m
Avalanche Problem
Persistent weak layer
2000m
Wind slab
2000m
Weak layers in persistent weak layer remain the main danger, beware of fresh snowdrift accumulations
The avalanche risk is moderate above around 2000 metres and low below that. In the aspects from west to north to east, medium and occasionally large, dry slab avalanches can still be triggered by individuals in a few places. Such avalanche prone locations are rare but often not recognisable in the terrain. Take particular care at the transitions from little to more snow. In addition, fresh snowdrift accumulations form in the aspects from north-west to south-east, which can easily be temporarily disturbed by individuals. Danger areas are usually adjacent to ridgelines, behind terrain edges and in the entrance areas to steep gullies and bowls.
In sunny conditions, small loose snow avalanches can detach from extremely steep sunny slopes.
Snowpack
Between 5 and 15 cm of new fallen snow has accumulated over the past few days, including the coming night into Monday. New and wind slab snow lies in shady high areas on a soft, faceted snow surface. Otherwise, there is often an equally thin, non-load-bearing melt-freeze crust under the thin layer of fresh snow. Underneath this is a well-set sequence of compact, older drift snow layers, in which a crust is embedded in combination with faceted crystals. The connection at the transition to the old snow foundation, which consists mainly of deep rime, is still poor. Deep and sunny middle layers are largely snowed out.
Tendency
With some snowfall and wind in the night to Tuesday, the avalanche prone locations due to wind slab will increase slightly and the risk of avalanches will rise slightly.
Danger level
treeline
Avalanche Problem
Wind slab
Treeline
Beware snowdrifts: prone to triggering
Avalanche danger above the timberline is moderate, below that altitude danger is low. Fresh snowdrift accumulations can trigger slab avalanches even by minimum additional loading. Danger zones occur primarily in steep terrain and in wind-loaded gullies and bowls. Frequency and spread of avalanche prone locations increase with ascending altitude and during the course of the day. If avalanches on high-altitude shady slopes fracture down to deeper weak layers, they can in isolated cases then grow to larger size. Apart from the risks of being buried in snow masses, the danger of being swept along and forced to take a fall require caution. Particularly if there is solar radiation, small-to-medium sized avalanches are possible in steep rocky terrain.
Snowpack
From Saturday until Sunday morning there was about 15-20cm of fresh snow registered. As a result of brisk westerly winds, later on blowing at strong velocity, fresh snowdrift accumulations will be generated. These will be deposited on top of a loosely-pack layer and are prone to triggering. The mid-level part of the snowpack consists of well-settled, compact layers widespread which on high-altitude shady slopes cover a poorly structured old snowpack fundament.
Tendency
Avalanche danger will slowly diminish overall, however, intermittent N-NW winds will generate new snowdrift accumulations which will be prone to triggering. With solar radiation, the danger of wet-snow avalanches will increase over the course of each day.
Danger level
Low avalanche danger
Avalanche danger remains low. Wet snow slides are possible on steep slopes during the day, which can also be triggered by individual winter sports enthusiasts. Caution is still advised on shady slopes, where small slab avalanches are possible in persistent weak layers.
Snowpack
The clear nights of the last few days have allowed a melt-freeze crust to form, which softens again during the day with rising temperatures and sunlight. In shady locations, it lasts longer.
Depending on the altitude and aspect, the snowpack varies on the surface: sometimes crusted, sometimes less stabilised and often moist up to high altitudes. In gullies and bowls, the wind slab is usually well stabilised. Faceted crystals are partially weakening the snow base, fundament at higher elevations in the northern sector.
As temperatures remain mild, the snow is melting. There is little snow below around 1400 metres and below around 1600 metres on the sunny slopes.
Tendency
The avalanche risk remains unchanged. It will continue to cool down on Tuesday night and there will be isolated unproductive snow showers. The westerly wind will ease temporarily during the night, but will pick up again during the day on Tuesday and then blow increasingly from the north-west.
Danger level
1800m
Avalanche Problem
Persistent weak layer
1800m
Take into account persistent weak layers and avoid small-scale pillows of wind drifted snow
The avalanche risk is low. Medium-sized slab avalanches can still be triggered in a few hard-to-recognise places, especially in the extended northern sector above 1800 m, but usually only with a large additional load. This is in particular at the transitions from little to more snow. Fresh, small-scale pillows of wind drifted snow in the areas adjacent to the ridgeline, crest or summit of the extended northern and eastern exposures are temporarily prone to triggering.
Snowpack
Once again, it is snowing unproductively. The little new and wind slab snow lies in shady high areas on a soft, faceted snow surface. Otherwise, there is often an equally thin, non-load-bearing melt-free crust under the thin layer of fresh snow. Underneath this is a well-set sequence of compact, older drift snow layers, in which a crust is embedded in combination with faceted crystals. The connection at the transition to the old snow foundation, which consists mainly of deep rime, is still poor. Deep and sunny middle layers are largely snowed out.
Tendency
With a brisk westerly wind, it will snow unproductively on Monday, the avalanche danger will not change significantly.
Danger level
2000m
Avalanche Problem
Persistent weak layer
2000m
Be aware of the local persistent weak layer problem!
The avalanche risk is generally low. However, on shady slopes in the higher elevations and transitions from little to more snow still need to be considered in some cases. Only isolated slab avalanches can still be triggered here by large additional loads. The danger of wet snow avalanches is low.
Snowpack
Depending on the altitude and aspect, the snowpack is differently developed on the surface, partly crusted, partly less stabilised and often moist up to high altitudes in the interior and wet towards the ground. The snow base, fundament remains high and weakened on shady slopes. Low and widespread middle elevations are bare, in some places there is only a little snow.
Tendency
Despite some new fallen snow, the avalanche situation hardly changes.
Danger level
treeline
Avalanche Problem
Wind slab
Treeline
Be aware of the risk of falling!
The avalanche risk is low. Fresh wind slabs that develop during the daytime changes can be problematic. Occasionally, smaller slab avalanches can be triggered with little additional load in steep terrain adjacent to ridgelines. On shady slopes at high altitudes, deeper weak layers can be disturbed in isolated cases with large additional loads.
Snowpack
Fresh, small snowdrift accumulations form with winds from north-westerly directions. Some of these come to rest on a soft layer of snow and can be prone to triggering. In shady high altitudes, layers of faceted crystals can be found deep in the otherwise compact old snowpack. At medium altitudes, the snowpack is wet towards the ground.
Tendency
The avalanche danger remains low.
Danger level
2000m
Avalanche Problem
Persistent weak layer
2000m
Persistent weak layer problem.
The avalanche risk is low. Nevertheless, there is still a persistent weak layer problem in the extended northern sector. Occasionally, mainly in very steep gullies and bowls, slab avalanches can be triggered by people. The avalanche prone locations are usually difficult to recognise and are often located in transition areas from a little to a lot of snow.
On sunny slopes, incoming radiation increases the probability of triggering small wet snow avalanches.
In steep terrain, there is a risk of falling on the hard snow surface.
Snowpack
The snowpack is set. As it cools, the snowpack surface becomes hard. In the persistent weak layer, floating snow weakens the snow layering. The snow inside the snowpack is moist to wet, depending on the altitudes.
Tendency
It will continue to cool down on Tuesday night and snow showers will fall on the northern side of the Alps. The risk of avalanches may increase slightly.
Danger level
Low risk of isolated wet snow avalanches
The avalanche risk is low. In the entrance areas of steep gullies on the shady slopes, small snow slabs can still be triggered in exceptional cases with a large additional load. The risk of being swept away and falling on icy surfaces that may be thinly covered with snow and therefore difficult to recognise generally outweighs the risk of burial.
Snowpack
It snows unproductively during the night. Low and sunny mid-altitude areas are snowed out. Where present, the snowpack is moist to wet and well-set right up to the summit areas. Due to the many clouds, the snow surface can hardly outgoing longwave radiation overnight, no stable melt-freeze crust forms. In the higher areas on shady slopes, there are still weak layers of large faceted crystals in the lower part of the snowpack, especially near the ground.
Tendency
With some snowfall and wind, small-scale avalanche prone locations will develop in the night to Tuesday due to fresh wind slab and the avalanche risk will increase slightly.
