nördliches Prättigau

A generally favourable avalanche situation will prevail.

Single winter sport participants can release avalanches in some places. These can release the weakly bonded old snow as well and reach medium size. The avalanche prone locations are rather rare but are barely recognisable, even to the trained eye. In addition the fresh and older wind slabs are prone to triggering in some cases still. Careful route selection is recommended.

Snowpack Snow depths on flat fields at the measurement stations at high altitudes are recording one-third to two-thirds of otherwise customary snow-depth measurements. With the exception of the northern and the furthermost western parts of the Lower Valais, the snow cover contains expansively metamorphosed (faceted) and loosely-packed layers over widespread areas. On the northern flank of the Alps these layers are frequently located in the uppermost sector of the snow cover; in the southern part of the Valais and in Grisons, the entire snow cover is frequently expansively metamorphosed (faceted) and loosely-packed. The frequency of places where dry-snow slab avalanches can be triggered is diminishing. These places still lie on shady, very steep slopes more than anywhere else. As a consequence of solar radiation and higher daytime temperatures, wet-snow and gliding avalanches are possible on very steep south-facing slopes during the course of the day. In the southern Valais and in Grisons more than anywhere else, wet slab avalanches can in isolated cases also be triggered by persons. Observed weather review Sunday, 19.02.2023 Following a night of predominantly clear skies it was generally sunny on Sunday. Fresh snow - Temperature At midday at 2000 m, between +4 °C in the western and the southern regions and +1 °C in the eastern regions. Wind Winds were westerly to northwesterly,

• blowing predominantly at light strength in the western regions,
• blowing at light to moderate strength in the remaining regions of Switzerland, blowing intermittently at strong velocity at elevated altitudes.

Weather forecast through Monday, 20.02.2023 Skies on Sunday night will be clear for the most part. In the central and eastern sectors of the northern flank of the Alps as well as in Grisons, nocturnal outgoing longwave radiation will be intermittently reduced as a consequence of low lying cloud cover. During the daytime on Monday it will be predominantly sunny and mild. Fresh snow - Temperature Temperatures are rising, at midday at 2000 m, to between +7 °C in the western and the southern regions and +3 °C in the eastern regions. Wind

• Winds will be blowing at moderate to strong velocity at heightened altitudes from northwesterly directions during the night,
• during the daytime hours blowing mostly at light strength from northerly directions.

Outlook through Wednesday, 22.02.2023 Tuesday Following a night of predominantly clear skies it will be sunny on Tuesday, accompanied by light winds. With the zero-degree level at 3000 m it is inordinately mild for this juncture of the season. The danger of dry-snow avalanches is not expected to change significantly. The danger of wet-snow avalanches will increase somewhat on steep sunny slopes during the course of the day. Wednesday On Tuesday night, cloud cover will move in from the west, nighttime skies will be only partly clear. During the daytime hours on Wednesday skies will be overcast by and large and during the afternoon light precipitation is expected to set in from the west. However, also sunny intervals are anticipated. In the eastern regions it will remain sunny for longer. As a consequence of reduced nocturnal outgoing longwave radiation, the danger of wet-snow avalanches will increase somewhat more quickly during the daytime.