Monte Rosa

As a consequence of new snow and a gathering strong southerly wind, avalanche prone wind slabs will form. They can in some places be released by people and reach medium size. The number and size of avalanche prone locations will increase as the day progresses. In the afternoon danger level 3 (considerable) will be reached. Fresh wind slabs are to be avoided. As the day progresses as a consequence of the rain there will be an increase in the danger of wet avalanches. In particular on north facing slopes small and, in isolated cases, medium-sized wet avalanches are to be expected below approximately 2200 m. Meticulous route selection is recommended.

As a consequence of new fallen snow and winds, fresh snowdrift accumulations will be generated at high altitudes during the course of the day. These snowdrift accumulations are prone to triggering in some places. Prior to the current round of snowfall the snowpack showed pronounced effects from sunshine over widespread areas. Thus, the bonding to the layers of fresh snow and fresh snowdrifts is generally favourable. Only on north-facing slopes in high alpine regions was the snowpack surface still loosely packed, thus, it forms a weak base. South-facing slopes are thoroughly wet far up into high alpine regions; west-facing and east-facing slopes are wet below approximately 3000 m; north-facing slopes below approximately 2400 m. As a result of rainfall up to 2200 m, wet-snow and gliding avalanches are possible; however, since the snowpack at this altitude belt is already wet, no large-sized avalanches are anticipated.

Nocturnal skies on Thursday were partly clear in the northern regions, in the southern and eastern regions skies were overcast. During the daytime hours on Friday it was partly sunny in the northern regions in spite of some cloudbanks; in the southern regions and in Grisons, skies were predominantly overcast. From place to place during the afternoon, a small bit of snowfall was registered above 2400 m. Fresh snow: - Temperature: At midday at 2000 m, approximately +5 °C. Wind: Winds were blowing at light strength. During Friday night, precipitation is expected to set in from the southwest. During the daytime hours on Saturday, skies in the southern regions will be heavily overcast, in the northern regions variably cloudy accompanied by brief sunny intervals. In the southern regions more than anywhere else, yet also in the western regions, intermittent precipitation is expected in the morning, becoming heavier in the afternoon. Fresh snow: Between Friday afternoon and Saturday afternoon the following amounts of fresh snow are expected above 2200 m:

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

Sunday: On Saturday night the precipitation is expected to intensify, the snowfall level will descend to 1600 m. During the daytime hours on Sunday, skies will be variably cloudy on both northern and southern flanks of the Alps and precipitation is expected from the south. On the Main Alpine Ridge and in the Upper Valais, 20 to 40 cm of fresh snow is expected over widespread areas, up to 60 cm of fresh snow on the Main Alpine Ridge from Monte Rosa into the Bernina region. Winds on Saturday night will be blowing at storm strength in some places at high altitudes, during the daytime hours on Sunday at moderate to strong velocity, from southerly directions. The danger of dry-snow avalanches is expected to increase significantly along the Main Alpine Ridge, at high altitudes Danger Level 4 (high) can be reached from place to place. In the remaining regions of Switzerland the danger will stem from freshly generated snowdrift accumulations more than anything else. The danger of wet-snow avalanches will tend to decrease as temperatures drop. Monday: On Monday, skies will range from variably cloudy to heavily overcast. Precipitation will continue to fall intermittently, particularly on the northern flank of the Alps. The danger of dry-snow avalanches will remain upright, and are assessed as treacherous in the areas where there is precipitation. As a result of the precipitation gradually slackening off and the southerly winds easing, naturally triggered avalanche activity is expected to diminish. In regions where there is solar radiation, moist slides can be expected to release from the fresh fallen snow.