Pre Alps

Beware fresh snowdrifts and gliding snow

Beware fresh snowdrifts and gliding snow

Fresh and older snowdrifts at high altitudes require caution, they are often blanketed and hard to recognize. Danger zones occur in ridgeline terrain, behind discontinuities and in wind-loaded gullies and bowls; they increase in both size and frequency with ascending altitude. In high alpine regions the danger zones are more frequent. Due to warmth and radiation, slides and loose-snow avalanches are possible, esp. on sunny slopes. Below 2600 m, glide-snow avalanches continue to be possible.

Due to strong-to-stormy foehn winds, often hard, mostly thin and frequently trigger-prone snowdrift accumulations have been generated since Tuesday. On Thursday, 10-20 cm of fresh snow was registered, now blanketing older snowdrifts which were deposited by strong SW winds atop soft layers or atop graupel, thus, are prone to triggering. Below 2000 m the old snowpack is thoroughly moist, wet down to the ground, this reinforces gliding over smooth ground. Very little snow on the ground below 1500 m.

Nocturnal hours: Scattered clouds, good outgoing longwave radiation. Winds wil arise, which will hamper this effect. Friday daytime: Good Friday will be marked by strong-to-stormy foehn winds. Clear skies and sunshine. At 2000 m: 5 degrees. Strong to stormy SW winds.

Holy Saturday and Easter Sunday will continue the foehn situation. Avalanche danger levels are not expected to change significantly.