südliches Urseren

Considerable avalanche danger will be encountered over a wide area.

Avalanches can be released in the old snowpack and reach dangerously large size. Caution is to be exercised at transitions from a shallow to a deep snowpack, when entering gullies and bowls for example. Whumpfing sounds can indicate the danger. Remotely triggered avalanches are possible. Fresh and somewhat older wind slabs are in some cases prone to triggering, in particular at elevated altitudes. Backcountry touring and other off-piste activities call for experience in the assessment of avalanche danger and caution.

Snowpack At low and intermediate altitudes the snow cover on flat terrain is well below average for this time of year. At altitudes above 2500 m the snow depths are mostly slightly below average; in Valais they are average over a wide area. At 2500 m, approximately 1 m of snow is lying in northern Valais, Bedretto and the Upper Valle Maggia, and 50 to 80 cm are to be found over a wide area elsewhere; in central Grisons and Engadine 30 to 50 cm are to be found. At altitudes below approximately 2500 m the snowpack has been influenced by warm temperatures and rain; at higher altitudes and in particular in the high alpine regions it has been significantly influenced by the wind from westerly directions. In particular in Valais, the Gotthard region, Ticino and Grisons, above 2200 to 2400 m the deeper snow layers are faceted and soft. They are covered by well bonded layers of various thickness. In particular in the inneralpine regions of both Valais and Grisons, avalanches can be triggered by people in these soft old layers of snow. Especially at elevated altitudes, both a little older and fresh snow drift accumulations can be released as avalanches in some places. Observed weather review Tuesday, 27.12.2022 On Monday night, snow fell on the main Alpine ridge and to the north. In the morning the precipitation ceased in the northeast, whereas in the west and south it was already mostly sunny. In the afternoon the skies cleared in the east as well. Fresh snow The snowfall level dropped from approximately 2000 m towards 1200 m. From Monday evening until Tuesday midday the following amounts of snow fell:

• In the extreme west of Lower Valais on the border to France and in the central and eastern parts of the northern flank of the Alps, excluding the Prealps: 15 to 30 cm
• Otherwise in Valais, on the northern flank of the Alps, in northern and central Grisons and in Lower Engadine: 5 to 15 cm
• Further south: smaller amounts or no precipitation

Temperature At midday at 2000 m: between -4 °C in the north and +2 °C in the south Wind From westerly directions

• During the night in the west and generally at elevated altitudes, moderate to strong
• During the day, light to moderate

Weather forecast through Wednesday, 28.12.2022 After a sometimes clear Tuesday night, it will be quite sunny during the day. Fresh snow - Temperature At midday at 2000 m: between 0 °C in the north and -3 °C in the south Wind From the west to southwest

• Becoming fresher on Tuesday night
• During the day in the inneralpine regions and in the south, mostly moderate; at elevated altitudes and in the west and north, generally strong

Outlook through Friday, 30.12.2022 Thursday During Wednesday night the skies will become overcast from the northwest, but in the east there will still be bright spells in the morning. The south will be partly sunny. A little precipitation will fall in the west and north. With a persistently strong westerly wind it will remain mild. The avalanche danger will not change significantly. Friday On Thursday night a little precipitation will arrive from the northwest and fall over a wide area. During the day there will be brief bright spells in particular in the inneralpine regions. In the afternoon precipitation will recommence in the west. With a persistently strong westerly wind it will remain mild. The avalanche danger may increase a little in the west and north on Thursday night, but it will not change significantly elsewhere.