Churfirsten and Rhine Valley
Flumserberg
Avalanche Problems
Wind slab
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Field notes
Look for fresh snow deposits on Slope facing downwind/ wind sheltered aspect. Snow deposits can attain several times average snow depth.EAWS glossary, in Usually a steep, elongated, eroded trench; typically prone to snowdrift accumulation.EAWS glossary and Rounded or elongated concavity; typically tending to accumulate snowdrift.EAWS glossary, and behind ridgelines and abrupt changes in terrain — these are where the wind has loaded the snow into slabs that are easy to trigger. Recent avalanches, shooting cracks under your weight, and Distinctive noise (resembling a “whumpf” sound) occurring when a weak layer beneath a slab collapses. The air of the weak layer is forced outside the snowpack, with the resulting whumpf sound being heard. The sound usually indicates an unstable situation and can be accompanied by surface cracking. A whumpf is a clear avalanche alert.EAWS glossary sounds are clear confirmations of the problem. The safest move is to avoid wind-loaded terrain entirely. NB wind signs alone don't always mean an avalanche problem exists, and the age of drifted snow is hard to judge.
Wet snow + Gliding snow
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Field notes
Wet snow
Rolling snowballs, deep penetration when you step or ski, and small natural slides are clear signals that the Snow deposited on the ground in a multiplicity of layers.EAWS glossary is losing strength. After a clear, cold night the surface often freezes into a strong supporting Layer of hard-compacted snow resulting from a melt-freeze process or wind.EAWS glossary, and conditions are favourable in the early morning. After a warm, overcast night, the problem may be present from the start of the day. Plan early returns and watch the runout zones below you.
Gliding snow
Almost impossible to predict precisely, even when the warning signs are visible. A crack visible on the snowpack surface formed by snow-gliding on steep, and particularly grass-covered slopes. Areas below slopes with visible glide cracks should be avoided whenever possible due to threat of gliding sluffs or avalanches.EAWS glossary — gaps that open in the Snow deposited on the ground in a multiplicity of layers.EAWS glossary down to the ground — are often precursors to release, but they don't tell you when. A glide avalanche can release minutes after the cracks appear, or weeks later, or not at all. Some release without any visible warning. Avoid lingering anywhere near glide cracks: above them, alongside them, or below in the runout.
Snowpack & Weather
Snowpack
The fresh snow and wind slabs from the past two days are lying on soft layers, especially on slopes that are protected from the wind, and in some places Transparent, frequently flat crystals forming on the snowpack when moist air settles on the surface. It forms most often during cold, clear, humid nights. Once it is blanketed by fresh fallen snow, surface hoar is one of the most critical weak layer. See also: www.snowcrystals.itEAWS glossary has also been covered by snow. With the mild temperatures, the wind slabs are settling and stabilising rapidly. However, it is still possible for avalanches to be triggered at the transition to the Snow layers deposited from earlier precipitation, prior to fresh fallen snow. Old snow layers consist of metamorphosed snow crystals.EAWS glossary.
Up to 2400 m, the Snow deposited on the ground in a multiplicity of layers.EAWS glossary has been soaked by the rain down to around 2100 m. The snowpack will stabilise somewhat during the mostly clear night into Tuesday.
On shady slopes above approximately 2400 m and in the Areas above approximately 3000 m (particularly glaciated areas).EAWS glossary in general, there are faceted Snowpack layer in which the crystals are poorly bonded and the layer has the potential to fail. Typical crystals in dry weak layers causing avalanches are : precipitation particles; surface hoar; faceted crystals; hollow crystals; graupel. Generally >1mm in size, loose grains with few bonds Wet weak layers can be formed by all snow crystal/grain types.EAWS glossary deep in the Snow layers deposited from earlier precipitation, prior to fresh fallen snow. Old snow layers consist of metamorphosed snow crystals.EAWS glossary. With the new and drifted snow of the past two days, fractures are again possible in isolated cases. Avalanches may then become large.
Weather review for Monday
There was still widespread precipitation in the north overnight to Monday. The snowfall level rose to around 2300 m. It was mostly sunny during the day.
Fresh snow
From Saturday night to Monday morning, the following amounts fell above around 2400 m:
- Northern flank of the Alps, northern Valais, northern Prättigau: 20 to 30 cm, locally up to 40 cm
- Rest of Valais, rest of Gotthard region, rest of northern Grisons: 10 to 20 cm
- Elsewhere less than 10 cm across a wide area, dry in the very south
Temperature
At midday at 2000 m, around +4 °C
Wind
From the west:
- Strong during the night in the north and generally at high altitudes, storm force at times
- Light to moderate during the day.
Weather forecast to Tuesday
After a mostly clear night, it will be sunny and very mild.
Fresh snow
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Temperature
At midday at 2000 m, between +8 °C in the north and +4 °C in the south
Wind
Light to moderate southwesterly
Outlook
After mostly clear nights, Wednesday and Thursday will be mostly sunny and mild. The zero-degree level will be around 3100 m on Wednesday and 2700 m on Thursday. There will be a light to moderate southwesterly wind.
The risk of dry avalanches will continue to decrease. The danger of wet avalanches will change over the course of the day and will increase a little during the day. Gliding avalanches are still possible on steep grassy slopes.