Navigation mit Access Keys

SLF HomeAvalanche bulletin and snow situation

Main menu

 

Avalanche bulletin through Monday, 23 April 2018

Full-depth and wet avalanches as the day progresses

Edition: Su. 22.04., 17:00 Next update: Mo. 23.04., 17:00 Validity

Avalanche bulletin through Monday, 23 April 2018

Full-depth and wet avalanches as the day progresses

Edition Su. 22.04., 17:00 Next update Mo. 23.04., 18:00 Validity

Avalanche bulletin through Monday, 23 April 2018

Full-depth and wet avalanches as the day progresses

Edition Su. 22.04., 17:00 Next update Mo. 23.04., 17:00 Validity

Avalanche bulletin through Monday, 23 April 2018

Full-depth and wet avalanches as the day progresses

Edition Su. 22.04., 17:00 Next update Mo. 23.04., 17:00 Validity

 
Level 1, low

Dry avalanches:

Individual avalanche prone locations for dry avalanches are to be found in particular in extremely steep terrain and adjacent to the ridge line. Caution is to be exercised in particular on north facing slopes in high Alpine regions. Restraint should be exercised because avalanches can sweep people along and give rise to falls.

Wet avalanches as day progresses

Danger map Wet

see also snowpack and weather

Level 2, moderate

Wet avalanches as day progresses

Outgoing longwave radiation during the night will be reduced. The danger of full-depth and wet avalanches will already be elevated in the early morning. In the late morning as a consequence of warming during the day there will be an additional increase in the danger of wet and full-depth avalanches. From origins in starting zones where no previous releases have taken place full-depth and wet avalanches are to be expected, including quite large ones. The avalanche prone locations are to be found in all aspects. Backcountry tours should be started very early and concluded timely. Caution is to be exercised in areas with glide cracks.

Dry avalanches

Danger map Dry

see also snowpack and weather

Level 3, considerable

Wet avalanches as day progresses

Outgoing longwave radiation during the night will be reduced. The danger of full-depth and wet avalanches will already be elevated in the early morning. In the late morning as a consequence of warming during the day there will be an additional increase in the danger of wet and full-depth avalanches. Full-depth and wet avalanches are to be expected. The avalanche prone locations are to be found in particular in east to south to west facing aspects below approximately 3000 m and on north facing slopes below approximately 2500 m. Large avalanches are possible in starting zones where no previous releases have taken place. In avalanche paths that are already filled with snow in particular these can in some cases reach intermediate altitudes. Exposed parts of transportation routes can be endangered. Backcountry tours, off-piste skiing and ascents to alpine cabins should be started very early and concluded timely. Areas with glide cracks are to be avoided as far as possible.

Dry avalanches

Danger map Dry

see also snowpack and weather

Full-depth and wet avalanches as the day progresses
Edition: 22.4.2018, 17:00 / Next update: 23.4.2018, 18:00
Snowpack
The snow cover on steep, south-facing slopes is thoroughly wet up as far as high alpine regions. On north-facing slopes the snowpack is becoming increasingly wet as high up as approximately 2500 m. In the next few days the nights will not be as clear as in recent days; for that reason, only a thin crust at best will be able to form. Below approximately 2000 m, the snowpack surface can hardly freeze at night. As a result of solar radiation and daytime warming, the snowpack subsequently forfeits much of its stability quite rapidly during the course of the morning. Wet-snow and gliding-snow avalanches can be expected. Due to the extraordinary snow depths in many places, these avalanches can in isolated cases grow to large size.
Avalanche prone locations for dry-snow avalanches are found on north-facing slopes in high alpine regions more than anywhere else, however they occur seldom.
The snow line on north-facing slopes of the northern flank of the Alps is at 1200 to 1400 m; in other regions of Switzerland it is at 1600 to 1800 m. On south-facing slopes it is approximately 400 m higher.
Observed weather on Sunday, 22.04.2018
Following a night of clear skies it was sunny and quite mild. During the afternoon there was some convective cloud build-up in northern regions more than anywhere else.
Fresh snow
-
Temperature
At midday at 2000 m, between +8 °C and +12 °C. The zero-degree level will be between 3300 and 3700 m.
Wind
Winds were predominantly light.
Weather forecast through Monday, 23.04.2018
Nighttime skies will be only partially clear, with high altitude cloudbanks. The nocturnal outgoing radiation of the snowpack will be reduced. During the daytime it will be quite sunny, in spite of extensive high-altitude cloudbanks; it will even be predominantly sunny in the Valais, Ticino, central and southern Grisons. During the course of the afternoon, cloud cover will move in from the northwest and as evening approaches showers will set in.
Fresh snow
During the afternoon in high alpine regions on the northern flank of the Alps, a few centimeters of fresh snow are possible.
Temperature
At midday at 2000 m, +8 °C. The zero-degree level will be at 3200 m.
Wind
The southwesterly winds will intensify during the course of the day, blowing at moderate to strong velocity in high alpine regions on the northern flank of the Alps during the afternoon. In the other regions of Switzerland, winds will be predominantly light.
Outlook through Wednesday, 25.04.2018
Tuesday
On Monday night, skies will initially be overcast accompanied by a small amount of precipitation, subsequently skies will clear from the west. The nocturnal outgoing radiation will be reduced, particularly in eastern regions. During the daytime, following the withdrawal of residual cloud in eastern regions, it will be quite sunny despite high-altitude cloudbanks.
Due to the reduced nocturnal outgoing radiation, the danger of wet-snow and gliding-snow avalanches will be heightened even in the morning hours, particularly in northern and in eastern regions. In western and in southern regions, the avalanche situation will be more favourable in the mornings. The danger of dry-snow avalanches is not expected to change significantly.
Wednesday
On Wednesday, following a night of partially clear skies, it is expected to be quite sunny. During the course of the day, showers are anticipated in northern regions more than anywhere else. The danger of wet-snow and gliding-snow avalanches will be somewhat heightened already during the morning hours, subsequently the danger levels will increase rapidly over the course of the day. The danger of dry-snow avalanches is not expected to change significantly.
 

Your observations can improve the quality of the avalanche bulletin. We are very grateful for any reports and photos received.

Please report your observations of avalanches or alarm signs, or your estimation of the avalanche danger, or simply send us a picture illustrating the current situation. Your report from the field will be considered along with all the other information when we assess the avalanche danger. It is impossible, however, to reflect the exact content of each individual report in the avalanche bulletin.

The best way to file a report is by completing the interactive form on this page. If your report is to be used in the 5 pm avalanche bulletin, it should be submitted before 2:30 pm if possible. Reports received later will normally be given consideration in the next assessment.

Other reporting options:

Full-depth and wet avalanches as the day progresses
Edition: 22.4.2018, 17:00 / Next update: 23.4.2018, 18:00
Snowpack
The snow cover on steep, south-facing slopes is thoroughly wet up as far as high alpine regions. On north-facing slopes the snowpack is becoming increasingly wet as high up as approximately 2500 m. In the next few days the nights will not be as clear as in recent days; for that reason, only a thin crust at best will be able to form. Below approximately 2000 m, the snowpack surface can hardly freeze at night. As a result of solar radiation and daytime warming, the snowpack subsequently forfeits much of its stability quite rapidly during the course of the morning. Wet-snow and gliding-snow avalanches can be expected. Due to the extraordinary snow depths in many places, these avalanches can in isolated cases grow to large size.
Avalanche prone locations for dry-snow avalanches are found on north-facing slopes in high alpine regions more than anywhere else, however they occur seldom.
The snow line on north-facing slopes of the northern flank of the Alps is at 1200 to 1400 m; in other regions of Switzerland it is at 1600 to 1800 m. On south-facing slopes it is approximately 400 m higher.
Observed weather on Sunday, 22.04.2018
Following a night of clear skies it was sunny and quite mild. During the afternoon there was some convective cloud build-up in northern regions more than anywhere else.
Fresh snow
-
Temperature
At midday at 2000 m, between +8 °C and +12 °C. The zero-degree level will be between 3300 and 3700 m.
Wind
Winds were predominantly light.
Weather forecast through Monday, 23.04.2018
Nighttime skies will be only partially clear, with high altitude cloudbanks. The nocturnal outgoing radiation of the snowpack will be reduced. During the daytime it will be quite sunny, in spite of extensive high-altitude cloudbanks; it will even be predominantly sunny in the Valais, Ticino, central and southern Grisons. During the course of the afternoon, cloud cover will move in from the northwest and as evening approaches showers will set in.
Fresh snow
During the afternoon in high alpine regions on the northern flank of the Alps, a few centimeters of fresh snow are possible.
Temperature
At midday at 2000 m, +8 °C. The zero-degree level will be at 3200 m.
Wind
The southwesterly winds will intensify during the course of the day, blowing at moderate to strong velocity in high alpine regions on the northern flank of the Alps during the afternoon. In the other regions of Switzerland, winds will be predominantly light.
Outlook through Wednesday, 25.04.2018
Tuesday
On Monday night, skies will initially be overcast accompanied by a small amount of precipitation, subsequently skies will clear from the west. The nocturnal outgoing radiation will be reduced, particularly in eastern regions. During the daytime, following the withdrawal of residual cloud in eastern regions, it will be quite sunny despite high-altitude cloudbanks.
Due to the reduced nocturnal outgoing radiation, the danger of wet-snow and gliding-snow avalanches will be heightened even in the morning hours, particularly in northern and in eastern regions. In western and in southern regions, the avalanche situation will be more favourable in the mornings. The danger of dry-snow avalanches is not expected to change significantly.
Wednesday
On Wednesday, following a night of partially clear skies, it is expected to be quite sunny. During the course of the day, showers are anticipated in northern regions more than anywhere else. The danger of wet-snow and gliding-snow avalanches will be somewhat heightened already during the morning hours, subsequently the danger levels will increase rapidly over the course of the day. The danger of dry-snow avalanches is not expected to change significantly.

Latest avalanche bulletins

 

Have you observed alarm signs or an avalanche?

Your observations can improve the quality of the avalanche bulletin. We are very grateful for any reports and photos received.

 

More information about observations

Please report your observations of avalanches or alarm signs, or your estimation of the avalanche danger, or simply send us a picture illustrating the current situation. Your report from the field will be considered along with all the other information when we assess the avalanche danger. It is impossible, however, to reflect the exact content of each individual report in the avalanche bulletin.

The best way to file a report is by completing the interactive form on this page. If your report is to be used in the 5 pm avalanche bulletin, it should be submitted before 2:30 pm if possible. Reports received later will normally be given consideration in the next assessment.

Other reporting options:

 

No avalanche bulletins are being published at the moment. Nevertheless, you should still stay up to date with the avalanche situation in the mountains, especially if there is fresh snow.

However, the SLF will, by way of exception, also issue avalanche bulletins in the summer in case of heavy snowfall. There are different ways you can be notified when these bulletins based on the snow situation are published:

  • by push alert on SLF's free White Risk mobile app: appearing in four languages (English, German, French and Italian), this can be downloaded from iTunes App Store (for iPhones) or Google Play Store (for Android);
  • by mobile text message (SMS): please send an SMS with the message START SLF SOMMER to the phone number 9234 – you can cancel this service at any time by sending an SMS with the message STOP SLF SOMMER; cost: CHF 0.20 per SMS;
  • via an RSS feed which informs you whenever an avalanche bulletin is published.

Depending on the snow and avalanche situation, the regular publication of avalanche bulletin recommences in November/December.

Latest avalanche bulletins

 

Have you observed alarm signs or an avalanche?

Your observations can improve the quality of the avalanche bulletin. We are very grateful for any reports and photos received.

 

More information about observations

Please report your observations of avalanches or alarm signs, or your estimation of the avalanche danger, or simply send us a picture illustrating the current situation. Your report from the field will be considered along with all the other information when we assess the avalanche danger. It is impossible, however, to reflect the exact content of each individual report in the avalanche bulletin.

The best way to file a report is by completing the interactive form on this page. If your report is to be used in the 5 pm avalanche bulletin, it should be submitted before 2:30 pm if possible. Reports received later will normally be given consideration in the next assessment.

Other reporting options:

Europäische Lawinengefahrenskala mit Empfehlungen