nördliches Urseren

Moderate avalanche danger will be encountered over a wide area. Wind slabs and weakly bonded old snow require caution.

In some places avalanches can be released in the old snowpack and reach dangerously large size. The prevalence of the avalanche prone locations will increase with altitude. They are difficult to recognise. In high Alpine regions these avalanche prone locations are to be found in all aspects. In addition the mostly small wind slabs of Thursday are prone to triggering in some cases still. They are to be evaluated with care and prudence in steep terrain. Backcountry touring and other off-piste activities call for defensive route selection.

Snowpack Below approximately 2200 m there is extraordinarily little snow on the ground for this juncture of the season, at low altitudes there is no snow whatsoever. 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 average values. The generally shallow snowpack below 2200 to 2400 m shows pronounced effects from higher temperatures and rainfall and, as a result of melt-freeze crusts, is also riddled with expansively metamorphosed (faceted) layers. At higher altitudes the more deeply embedded layers inside the snowpack are frequently faceted and loosely-packed. This is the case on west-facing, north-facing and east-facing slopes above 2200 to 2400 m and on south-facing slopes above approximately 2700 m. In the northern regions on Thursday at elevated altitudes, the small amounts of fresh fallen snow, and the somewhat more loosely-packed old snow on the Main Alpine Ridge and southwards therefrom, were transported. Observed weather review Thursday, 05.01.2023 In the Engadine there were more extensive bright intervals, in the remaining regions of Switzerland skies were frequently overcast. In the northern regions more than anywhere else there was precipitation registered until midday. The snowfall level lay at approximately 2000 m for the most part, in the western regions at about 2500 m from place to place. During the afternoon in the western regions it became sunny in the high alpine zones. Fresh snow Between Wednesday evening and Thursday midday, the following amounts of fresh snow were registered above approximately 2400 m:

• northern flank of the Alps: 5 to 10 cm over widespread areas;
• in the other regions of Switzerland, less; or else it remained dry.

Temperature At midday at 2000 m, between +1 °C in the northern regions and +4 °C in the southern regions. Wind

• Winds during the nocturnal hours were blowing at moderate to strong velocity from westerly directions, slackening off during the daytime hours;
• on the Main Alpine Ridge and southwards therefrom, moderate to (from place to place) strong-velocity northwesterly winds were blowing during the course of the day.

Weather forecast through Friday, 06.01.2023 Following a night of clear skies it will be sunny and mild in the mountains on Friday. Fresh snow - Temperature At midday at 2000 m, between +5 °C in the northern regions and +3 °C in the southern regions. Wind

• Winds on Thursday evening in the southern regions and at elevated altitudes also in the eastern regions will be blowing at strong velocity from northerly directions;
• on Friday, westerly to southwesterly winds will be blowing at light to moderate strength.

Outlook through Sunday, 08.01.2023 Saturday On Saturday it will be predominantly sunny in the mountains. In the northern regions it will be very mild and in the eastern Alpine valleys, foehn winds are expected to arise. On the Main Alpine Ridge and in the foehn-impacted regions of the north, small-sized snowdrift accumulations are expected to form. In the remaining regions of Switzerland, the avalanche danger levels are not expected to change significantly. Sunday Skies will be heavily overcast and above approximately 1400 m snowfall is anticipated in the western and the southeastern regions more than anywhere else. The amounts of anticipated fresh fallen snow are still uncertain. Avalanche danger levels are expected to increase somewhat, particularly in the western regions and in the eastern sector of the Main Alpine Ridge.