Day Risk Profile

Low

Moderate

Later

Avalanche Problems

Dry avalanches, whole day

No distinct problem 1

N, NE, NW

above 2600m

Dry avalanches can in isolated cases be released in near-surface layers. This applies in particular on extremely steep north facing slopes in Areas above approximately 3000 m (particularly glaciated areas).EAWS glossary. Mostly the avalanches are small. 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. The Avalanche Warning Service currently has only a small amount of information that has been collected in the field, so that the avalanche danger should be investigated especially thoroughly in the relevant locality.

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, W

The surface of the Snow deposited on the ground in a multiplicity of layers.EAWS glossary will only just freeze. As a consequence of warming during the day natural wet avalanches are possible. This applies in particular on steep north facing slopes between approximately 2200 and 2600 m, but in isolated cases also on very steep east and west facing slopes between approximately 2500 and 3000 m. Mostly avalanches are medium-sized. Backcountry tours and ascents to alpine cabins should be started early and 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

By Tuesday evening, snowdrift accumulations that are sometimes prone to triggering will have developed at high altitudes on the main Alpine ridge. These will be medium-sized on the main Alpine ridge in Valais while further east they will still mostly be small.

Over the often cloudy night into Tuesday, the surface of the Snow deposited on the ground in a multiplicity of layers.EAWS glossary will barely freeze, even at high altitudes. Despite the slight decrease in temperature, wet avalanches remain possible, especially on north-facing slopes between 2200 and 2600 m, where the snowpack is becoming saturated for the first time.

Weather review for Monday

The night into Monday was mostly cloudy and outgoing longwave radiation was low. Skies were mostly cloudy during the day. In Valais, a little snow fell above approximately 2300 m. In the east, there were sometimes extended bright spells.

Fresh snow

Five to 10 cm on the main Alpine ridge in Valais above approximately 2300 m and a few centimetres locally in the rest of Valais

Temperature

At midday at 2000 m, between +9 °C in the north and +6 °C in the south

Wind

Moderate to strong from the south

Weather forecast to Tuesday

Conditions will be mostly cloudy on the main Alpine ridge and south of there. Snow will fall at times above approximately 2000 m. Otherwise, conditions will be variably cloudy with extended bright spells in central Valais and those regions exposed to the foehn wind in central and eastern Switzerland.

Fresh snow

From Monday afternoon until Tuesday afternoon above approximately 2500 m:

main Alpine ridge in Valais: 15 to 25 cm
Aletsch region, main Alpine ridge from the Nufenen Pass to the Bernina region and south of there: 5 to 10 cm

Temperature

At midday at 2000 m, between +7 °C in the north and +2 °C in the south

Wind

Southerly

strong at times overnight
during the day, moderate to strong in the east, moderate in the west

Outlook to Thursday

On Wednesday and into the night to Thursday, there will be frequent precipitation. The snowfall level will initially be at 2000 m, dropping to 1800 m as the snowfall comes to an end. On Thursday, it will initially still be cloudy in the east and south, and very sunny in the west. Over the course of the day, alongside brighter spells, there is a possibility of cumulus clouds and isolated showers in all regions. On Wednesday, there will be sometimes strong southerly winds at high altitudes; elsewhere winds will be mostly light to moderate from the southwest. By Thursday night, 30 to 50 cm of snow is expected from eastern Ticino to the Bernina region and to the south of there above approximately 2500 m. In the Glarus Alps, in the Gotthard region and in central Grisons, up to 30 cm of fresh snow is expected with up to 20 cm falling in other regions.

There will be a widespread increase in the danger of dry avalanches in high altitudes, the danger rising significantly on Wednesday on the main Alpine ridge from eastern Ticino to the Bernina region. On Thursday, the avalanche situation will remain critical for snow sport participants, especially at high altitudes in those regions exposed to heavier precipitation. In all regions, there is still a possibility of isolated wet avalanches being triggered in deep layers of the Snow deposited on the ground in a multiplicity of layers.EAWS glossary, especially on north-facing slopes between 2200 and 2600 m.

Source

SLF

Issued

4 May 15:00 UTC

Valid until

5 May 15:00 UTC

Next update

5 May 15:00 UTC