südliches Urseren

In Valais a considerable avalanche danger will be encountered in some regions. Wind slabs and weakly bonded old snow require caution.

In some places avalanches can be triggered in the weakly bonded old snow and reach medium size in some cases. The fresh wind slabs are mostly small but in some cases prone to triggering. They are to be evaluated with care and prudence in steep terrain. Defensive route selection is recommended.

Snowpack At altitudes below approximately 2200 m there is extraordinarily little snow on the ground for this juncture of the season, at lower altitudes there is no snow whatsover on the ground. Even above 2200 m the snow depths are below average over widespread areas. Only in the Valais do the snow depths correspond to long-term averages in some places. The generally shallow snowpack below 2200 to 2400 m shows pronounced effects from higher temperatures and rainfall and, as a consequence of the melt-freeze crusts, is also riddled with expansively metamorphosed (faceted) layers. At elevated altitudes the more deeply embedded layers inside the snowpack are often faceted and loosely-packed. This applies to west-facing, north-facing and east-facing slopes above 2200 to 2400 m and to south-facing slopes above approximately 2700 m. As a consequence of the southwesterly winds and southerly foehn wind over the last few days, snowdrift accumulations have been generated at heightened altitudes. These snowdrift masses are still prone to triggering in some places. As a result of the daytime rise in temperatures and solar radiation, the snowpack on very steep south-facing slopes will become weakened during the course of the day. In the western and the northern regions more than anywhere else, moist slides and gliding avalanches are possible. Observed weather review Sunday, 01.01.2023 On the southern flank of the Alps skies were overcast, in the remaining regions of Switzerland it was predominantly sunny. Fresh snow - Temperature At midday at 2000 m, between +7 °C in the northern regions and +1 °C in the southern regions. Wind Winds were blowing predominantly at moderate strength, intermittently at strong velocity, from southerly to southerwesterly directions. Weather forecast through Monday, 02.01.2023 On the southern flank of the Alps skies will be overcast. Above approximately 1700 m a small amount of snowfall is possible. In the remaining regions of Switzerland it will be predominantly sunny following a night of clear skies. During the afternoon, cloud cover will move in from the northwest. Fresh snow In the southern regions, a small amount of snowfall is possible above approximately 1700 m. Temperature At midday at 2000 m, 0 °C in the southern regions and +5 °C in the northern regions; temperatures are expected to drop there as well during the afternoon. Wind Winds will be southerly to southwesterly,

• in the northern regions and in general at elevated altitudes, blowing at moderate to strong velocity;
• in the other regions of Switzerland blowing at light to moderate strength.

Outlook through Wednesday, 04.01.2023 On Monday night, light precipitation is expected to set in from the north above approximately 1500 m. During the daytime hours on Tuesday, a small amount of snowfall is anticipated in the northern regions, in the Valais and the southern regions it is expected to clear up to an increasing degree. On Wednesday it will be rather sunny. Winds will slacken off, on both days they will be blowing at light to moderate strength from westerly directions. The danger of dry-snow avalanches is expected to incrementally diminish.