With the mild temperatures of the last two weeks, moisture penetration into the snowpackSnow deposited on the ground in a multiplicity of layers.EAWS glossary is already well advanced. At present, it is only increasing slowly. North-facing slopes at altitudes between 2200 and 2500 m are most susceptible to moisture penetration. On east- and west-facing slopes, the critical altitudes are somewhat higher, at approximately between 2500 and 2800 m. On south-facing slopes, moisture penetration into the snowpack extends as far as the high alpine regionsAreas above approximately 3000 m (particularly glaciated areas).EAWS glossary. It is on these aspectsDirection in which a slope faces as indicated by compass direction of the fall line; i.e. a north slope faces in a northerly direction.EAWS glossary and at these altitudes that isolated large or occasionally also very large wet slab avalanchesThe 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 may be triggered naturally.

In Grisons, the weak layersSnowpack 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 old snowpackSnow layers deposited from earlier precipitation, prior to fresh fallen snow. Old snow layers consist of metamorphosed snow crystals.EAWS glossary are the least deeply buried, and it is here that wet slab avalanchesThe 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 are likely also to be triggered by human activity. WhumpfingDistinctive 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 continue to be a possible indication of a weak snowpackSnow deposited on the ground in a multiplicity of layers.EAWS glossary.

At higher altitudes, where the snowpackSnow deposited on the ground in a multiplicity of layers.EAWS glossary is still dry, the weak layersSnowpack 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 old snowpackSnow layers deposited from earlier precipitation, prior to fresh fallen snow. Old snow layers consist of metamorphosed snow crystals.EAWS glossary must continue to be assessed with caution. However, dry avalanches have been rare in recent days.

During the first half of the night, the last precipitation fell in the northeast and in the south. During the day, it was mostly sunny in the west and south, and partly cloudy in the northeast.

Fresh snow

A few centimetres locally above approximately 2400 m

Temperature

At midday at 2000 m, between +5 °C in the southwest and 0 °C in the northeast

Wind

Moderate during the night, mostly light during the day from westerly directions

The night into Tuesday will be mostly clear despite some clouds, with partly cloudy conditions in the northeast. During the day, it will be mostly sunny. On the central and eastern northern flank of the Alps and in the Prättigau, it will be cloudy.

Fresh snow

-

Temperature

At midday at 2000 m, between +4 °C in the southwest and -2 °C in the northeast

Wind

Light to moderate from westerly directions

During the night into Wednesday, it will be cloudy in the far south with some showers, while during the day it will become increasingly sunny. In the north, Wednesday will be mainly sunny after a mostly clear night. The night into Thursday will be clear in many regions. During the day, it will be sunny.

The danger of dry avalanches will not change significantly. The danger of wet avalanches will increase during each day. Off-piste skiing and hut ascents should be completed in good time.