Allgäu Alps West

Naturally triggered avalanches expected during course of day

Dangerous avalanche situation widespread during daytime. Main danger: wet snow.

Due to starkly reduced nocturnal outgoing radiation in many places, the snowpack is hardly freezing except in high alpine regions. Below about 2500m the snowpack is softened already in early morning and persons can trigger wet-snow slab avalanches. As a result of daytime warming and solar radiation, frequency of avalanche prone locations rapidly increases so that during afternoon, numerous naturally triggered wet-snow avalanches can be expected in all aspects below about 2600m, above that altitude on sunny slopes. Caution urged above all on steep shady slopes at 2200-2600m, where wet-snow avalanches can fracture in the weak old snow and grow to large size, in isolated cases also in freeriding terrain which has been heavily tracked and skied. Avalanches can plummet into steep gullies down to forested areas. Backcountry tours and ascents to refuges need to be launched early in the day and brought to a close early. In addition, winter sports enthusiasts can in isolated cases trigger avalanches in near-surface weak layers on high-altitude shady slopes. Such danger zones are impossible to recognize.

Following starkly reduced outgoing radiation, the snowpack is hardly freezing at night. At altitudes of 1800-2500m the ground level layer of rotten snow is thoroughly wet, even on north-facing slopes, and is prone to triggering. On high-altitude shady slopes there are unfavorable intermediate layers in the uppermost layer of the snowpack which in places can be triggered. A thick mid-section of compact layers blankets the deep hoar and faceted crystals at the base of the snowpack.

Heavily clouded skies during the night, followed by dispersal in early morning and solar radiation. In afternoon, rain showers from place to place from the residual and convective clouds. Rising temperatures at all altitudes. Temperature at 2000m: 0 - +4 degrees; at 3000m: -5 to +2 degrees. Light winds at high altitudes.

On Wednesday night, reduced outgoing longwave radiation is again anticipated. Gradually, high-pressure front conditions with mild temperatures will prevail. The snowpack surface barely freezes and rapidly softens in the morning. Due to daytime warming and solar radiation, danger of wet-snow avalanches increases during daytime hours.