Day Risk Profile

Low

Moderate

Later

Avalanche Problems

Dry avalanches, whole day

No distinct problem 1

N, NE, E, SE, W, NW

above 2200m

Individual Locations delineated by aspect or altitude where avalanches can trigger and people or objects are at risk.EAWS glossary for dry avalanches are to be found in particular in extremely steep terrain. Caution is to be exercised on rather lightly snow-covered shady slopes in little used backcountry terrain. Apart from the danger of being buried, restraint should be exercised as well in view of the danger of avalanches sweeping people along and giving rise to falls.

Field notes

SLF uses this label when no single problem dominates the assessment, often on lower-danger days. It doesn't mean conditions are safe: any avalanche type is still possible, and normal caution applies. On stable days this is usually a signal to enjoy the mountains with general awareness; on less-stable days where the assessment is still inconclusive, it's a signal to be cautious specifically because there's no clear pattern to follow.

Source: SLF Avalanche Bulletin Interpretation Guide

Wet-snow avalanches, as the day progresses

Wet snow 2

N, E, S, W

below 2500m

As the day progresses as a consequence of warming during the day and solar radiation there will be only a slight increase in the danger of wet avalanches. This applies in particular on very steep north facing slopes below approximately 2500 m, as well as on very steep east, south and west facing slopes between approximately 2500 and 3000 m. The wet avalanches can in isolated cases reach large size. Backcountry tours and ascents to alpine cabins should be concluded timely.

Field notes

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.

Source: SLF Avalanche Bulletin Interpretation Guide

Snowpack & Weather

Snowpack

Moisture penetration into the Snow deposited on the ground in a multiplicity of layers.EAWS glossary is well advanced. The most precarious areas are slopes where 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 in the Snow layers deposited from earlier precipitation, prior to fresh fallen snow. Old snow layers consist of metamorphosed snow crystals.EAWS glossary are becoming wet for the first time. At present, this mainly affects north-facing slopes between approximately 2200 and 2500 m, and east- and west-facing slopes between approximately 2500 and 2800 m. On south-facing slopes, the snowpack is thoroughly moist as far as into the Areas above approximately 3000 m (particularly glaciated areas).EAWS glossary. In Grisons, the weak layers in the old snowpack are the least deeply buried, which means that wet The abrupt release of a slab of snow on a mountain slope. After crack initiation and crack propagation in a weak layer the released slab comprises 3 elements: The weak layer, the gliding horizon and the slab. If the slope angle is steep enough, the slab will glide down. If the slope is not steep enough, the slab will settle down on the failed weak layer. Possibly a whumpf sound will follow due to air pressed out of the weak layer. The fracture line will be sharp edged.EAWS glossary can also be triggered by human activity in some places.

Higher up, the Snow deposited on the ground in a multiplicity of layers.EAWS glossary is still dry. There are still 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 in the Snow layers deposited from earlier precipitation, prior to fresh fallen snow. Old snow layers consist of metamorphosed snow crystals.EAWS glossary, but no more dry avalanches have been reported in recent days.

Weather review for Wednesday

In the south, it was very cloudy and a few snowflakes fell locally above 2000 m. There was rain in the Sotto Ceneri. Otherwise, the night was mostly clear and the day sunny.

Fresh snow

Temperature

At midday at 2000 m, around +2 °C

Wind

Often moderate from north to west during the night, mostly light during the day
Bise wind along the Prealps

Weather forecast to Thursday

In the far south, the night into Thursday will be cloudy with some rain; it will become increasingly sunny during the day. In the north, it will be mostly sunny after a mostly clear night.

Fresh snow

Temperature

At midday at 2000 m, around +5 °C

Wind

Light to moderate northeasterly

Outlook to Saturday

The nights will be clear, and with the dry air, the Snow deposited on the ground in a multiplicity of layers.EAWS glossary will freeze at high altitudes to become capable of bearing loads. The days will be sunny and mild; the zero-degree level will be around 3200 m. The winds will be mostly light.

The danger of dry avalanches will not change significantly. This means that in the early morning, touring conditions will be favourable over a wide area. Each day, the danger of wet avalanches will increase appreciably as the day progresses. Ski tours and hut ascents should be completed in good time.

Source

SLF

Issued

22 Apr 15:00 UTC

Valid until

23 Apr 15:00 UTC

Next update

23 Apr 15:00 UTC