südliches Urseren

Slight increase in avalanche danger in the course of the day.

Avalanches can in some cases be released in deep layers and reach medium size. Avalanche prone locations are to be found in particular at transitions from a shallow to a deep snowpack. As a consequence of a gathering strong northwesterly wind, mostly small wind slabs will form from the middle of the day. They are to be evaluated with care and prudence. Backcountry touring and other off-piste activities call for careful route selection.

Snowpack Snow cover layering in the furthermost western part of the Lower Valais is the most favourable. On the northern flank of the Alps the lowermost section of the snow cover is frequently well consolidated; above that sector, however, there are several expansively metamorphosed (faceted) layers embedded inside the snowpack. In the remaining regions of Switzerland there are numerous softened, expansively metamorphosed (faceted) layers evident between the consolidated layers of snow and crusts. These layers are particularly pronounced on slopes where the snow is shallow and where one breaks down to ground level on skis. Also the superficial layers of snow on wind-protected slopes are expansively metamorphosed (faceted) and loosely-packed to an increasing degree; furthermore there is surface hoar on the snowpack surface. On the northern flank of the Alps as well as in ridgeline terrain, in pass areas and in general at high altitudes, the snowpack surface frequently shows pronounced impact from winds. On Monday the northwesterly winds will intensify during the course of the day and snowdrift accumulations which are prone to triggering will be generated. Observed weather review Sunday, 29.01.2023 In the southern regions and in the mountain massifs it was predominantly sunny. Fresh snow - Temperature Temperatures have risen. At midday at 2000 m, -3 °C in the northern regions and -5 °C in the southern regions. Wind Winds were blowing from easterly to northeasterly directions,

• in the northern regions during the nocturnal hours on Saturday night at moderate strength;
• during the daytime hours blowing predominantly at light strength, intermittently at moderate velocity.

Weather forecast through Monday, 30.01.2023 Following a night of clear skies it is expected to be quite sunny to start with on Monday, subsequently it will become increasingly overcast from the northwest during the afternoon. Fresh snow - Temperature At midday at 2000 m, -6 °C in the northern regions and 0 °C in the southern regions. Wind Winds will be northwesterly,

• blowing at light to moderate strength during the nocturnal hours;
• during the daytime hours blowing at moderate to strong velocity, at strong to storm strength on the Main Alpine Ridge and in general at high altitudes;
• in the southern regions, northerly foehn wind is expected to arise during the course of the day.

Outlook through Wednesday, 01.02.2023 Tuesday On Monday evening in the northern regions, light snowfall is expected to set in which will then persist until Tuesday morning. Snowfall will extend down to low lying areas. By Tuesday morning in the Jura region, in the central and eastern sectors of the northern flank of the Alps, in northern Grisons as well as in the northern part of Lower Engadine, approximately 5 cm of fresh snow is anticipated, up to 10 cm from place to place. On Tuesday it will be partly sunny. In the northern and the eastern regions it will be temporarily sunny after the residual clouds have dispersed, in the afternoon it will again become increasingly overcast. In the northern regions, winds will slacken off, in the southern regions a moderate to strong velocity northerly wind will continue blowing. As a consequence of the winds, the small amount of fresh fallen snow as well as the loosely-packed old snow will be transported. Avalanche danger levels are expected to increase somewhat from region to region on Monday night. Wednesday It will be predominantly sunny. In the northern regions a moderate-strength, during the course of the day westerly wind will be blowing and intensifying to an increasing degree. In the southern regions, the northerly wind will persist. Avalanche danger levels are not expected to change significantly.