Schreckhorn

Considerable avalanche danger will be encountered in some regions.

Snowpack On north facing slopes above approximately 2500 m, fresh snow and snow drift accumulations are lying on loosely bonded layers; in Grisons, surface hoar has been covered with snow in some cases. Here in particular, the near-surface layers are prone to triggering in some instances. On north facing slopes between 2000 and 2500 m, for the first time this winter the snowpack is becoming wet and consequently being weakened. In Grisons in particular, in the last few days large avalanches have been released frequently in the deep, weak old snow on north facing slopes above approximately 2500 m. This danger still persists. In southern Valais and on the southern flank of the Alps, avalanches of this type can likewise not be ruled out. Solar radiation is expected to trigger wet loose snow avalanches in the fresh snow. Observed weather review Tuesday, 25.04.2023 The north was very cloudy, and above approximately 1200 m snow fell over a wide area. As the day progressed there were bright spells in the inneralpine regions. It was quite sunny in the south. Fresh snow From Monday afternoon until Tuesday afternoon the following amounts of snow fell above approximately 2400 m:

• Northern Alpine ridge: 15 to 25 cm
• Rest of the northern flank of the Alps, central Valais and Prättigau: 5 to 15 cm
• Elsewhere: a few centimetres, mostly dry in the south

Since the onset of the precipitation on Sunday afternoon, therefore, approximately 30 to 50 cm of snow has fallen on the northern flank of the Alps. Temperature At midday at 2000 m: about -3°C in the north and +1 °C in the south Wind Moderate from westerly directions Weather forecast through Wednesday, 26.04.2023 In the west and south the night will be mostly clear. In the northeast some final precipitation will have fallen by the morning. During the day it will be mostly sunny in the south and east. In the north it will be quite sunny at first, but in the afternoon cloud will build up from the west. Fresh snow From Tuesday afternoon until Wednesday morning the following amounts of snow will fall above approximately 2400 m:

• Central and eastern parts of the northern flank of the Alps as well as Prättigau: 5 to 10 cm
• Rest of Grisons: a few centimetres

Temperature At midday at 2000 m: between +2°C in the southwest and -1 °C in the northeast Wind From the west to northwest

• On Tuesday night on the main Alpine ridge and to the south, strong
• Otherwise mostly light to moderate

Outlook through Friday, 28.04.2023 Thursday Wednesday night will be partly clear; in the east it will remain overcast until the morning and some precipitation may fall. During the day it will be fairly sunny; in the northeast, extensive residual cloud will persist at first. It will become warmer again. The zero degree level will rise to approximately 2500 m. The wind will be light, moderate at times, from westerly directions. The danger of dry avalanches will continue to decrease. The danger of wet snow avalanches will vary during the day. Friday Thursday night will be overcast and precipitation will commence in the north. During the day it will be cloudy with showery precipitation in the north; the south will be partly sunny. The snowfall level will be between 2200 and 2600 m. The wind will be moderate to strong from the west. The danger of wet snow avalanches will already exist in the early morning because of rain and the absence of outgoing radiation. The danger of dry avalanches may increase a little in the high Alpine regions on the northern flank of the Alps.

As a consequence of new snow and wind from westerly directions, avalanche prone wind slabs formed. Single winter sport participants can release avalanches. Mostly these are medium-sized. The wind slabs are to be avoided in steep terrain. The prevalence of the avalanche prone locations will increase with altitude. Backcountry touring calls for experience in the assessment of avalanche danger and careful route selection.

The surface of the snowpack will cool hardly at all during the overcast night. Already in the early morning wet and gliding avalanches are possible, in particular below approximately 2400 m. Avalanches can reach large size in isolated cases in particular on north facing slopes.