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In the west and in the east a considerable avalanche danger will be encountered in some regions.

Fresh and older wind slabs are in some cases prone to triggering. They are to be evaluated with care and prudence in steep terrain. The prevalence of the avalanche prone locations will increase with altitude. Additionally in isolated cases avalanches can penetrate near-ground layers of the snowpack and reach dangerously large size. Caution is to be exercised in particular in areas where the snow cover is rather shallow on very steep north facing slopes above approximately 2400 m.

As a consequence of warming during the day and solar radiation wet avalanches are to be expected. In some cases these are medium-sized. On steep grassy slopes at any time gliding avalanches are possible. Caution is to be exercised in areas with glide cracks.

Snowpack Fresh fallen snow and freshly generated snowdrift accumulations from Thursday and Friday have been deposited on top of a loosely-packed old snow cover surface on north-facing slopes above approximately 2500 m, in Grisons atop surface hoar in some places. Particularly there, these weakened layers are still prone to triggering in some spots. On north-facing slopes between 2000 and 2500 m the snow cover became wet for the first time this winter and was weakened thereby. Higher up, the top layers were moistened. In Grisons more than anywhere else, numerous large-sized avalanches have triggered from the deeply embedded weakened layers of the old snow cover on north-facing slopes above approximately 2500 m over the last few days. Because the snowpack beneath the prognosticated fresh snowfall remains moist, this danger ongoingly persists. In the southern Valais and on the southern flank of the Alps, such avalanches can also not be excluded. Observed weather review Sunday, 23.04.2023 Following a night of overcast skies it became quite sunny from the west in the northern regions, subsequently cloud cover moved in once again. From place to place, there was precipitation in the form of showers. Fresh snow Above approximately 2200 m there was a few centimetres of fresh snow registered over widespread areas. Temperature At midday at 2000 m, between +6 °C in the northern regions and +2 °C in the southern regions. Wind Winds were frequently blowing at moderate velocity from southerly-to-southwesterly directions, in the foehn-impacted regions of the north at strong velocity in some places during the afternoon. Weather forecast through Monday, 24.04.2023 During the nocturnal hours, precipitation is anticipated in some places in the form of thunderstorms. During the daytime hours in the northern regions, skies will remain predominantly overcast with only a small amount of additional precipitation in the northeastern regions more than anywhere else. In the inneralpine regions it will be partly sunny, in the southern regions predominantly so. Fresh snow The snowfall level is expected to descend from 2200 m down to 1500 m in the northern regions and down to 1800 m in the southern regions. Between Sunday afternoon and Monday afternoon, the following amounts of fresh snow are anticipated above approximately 2500 m:

• furthermost western part of the Lower Valais: 20 to 30 cm;
• in the other regions of Switzerland: 15 to 25 cm over widespread areas; from the southern Upper Valais into the upper valleys of Maggia, less.

Temperature At midday at 2000 m, -1 °C in the northern regions and +1 °C in the southern regions. Wind Winds on the northern flank of the Alps and in general at elevated altitudes will be blowing at strong velocity in some places, in the other regions of Switzerland blowing at moderate velocity, initially from southwesterly, then shifting to northwesterly directions. Outlook through Wednesday, 26.04.2023 Tuesday Skies will be heavily overcast, and above approximately 1200 m snowfall is anticipated. Most of the fresh fallen snow is expected between the eastern Bernese Oberland as far as the Alpstein, with approximately 20 to 30 cm. During the daytime hours there will be bright intervals in the inneralpine regions, in the southern regions it will be predominantly sunny. Northwesterly winds will be blowing predominantly at moderate strength, on the Main Alpine Ridge at strong velocity in some places. The danger of dry-snow avalanches is expected to increase significantly on the northern flank of the Alps from the western Bernese Oberland as far as the Alpstein. In the other regions of Switzerland, avalanche danger is expected to increase slightly. In the southern regions, avalanche danger levels are not expected to change significantly. The danger of wet-snow avalanches will diminish significantly. Wednesday Nighttime skies in the southern regions will be clear. In the western regions, skies will clear up in the early part of the night; in the eastern regions, skies will clear only as of early morning on Wednesday. On Wednesday in the northern regions it will be quite sunny, in the southern regions fine weather conditions are forecast. On Tuesday evening on the Main Alpine Ridge and southwards therefrom, a strong to storm-strength northwesterly wind will be blowing, subsequently the wind will slacken off significantly and shift to westerly. On the Main Alpine Ridge and southwards therefrom, snowdrift accumulations can be generated at high altitudes. In the other regions of Switzerland, the danger of dry-snow avalanches is expected to decrease. During the course of the day, wet-snow avalanches can be expected to trigger from the fresh fallen snow.