2021-03-29T16:00:00+00:00 avalanche-warnings.eu 2021-03-29T22:00:00+00:00 2021-03-30T22:00:00+00:00 2021-03-29T22:00:00+00:00 2021-03-30T10:00:00+00:00 1 2021-03-30T10:00:00+00:00 2021-03-30T22:00:00+00:00 2 wet snow daytime cycle of naturally triggered avalanches old snow in shady and high-alpine terrain Avalanche danger will increase to moderate during the day In these classic springtime conditions, avalanche danger is subject to fluctuations, known as the daytime danger cycle. Through a combination of daytime warmth and solar radiation, naturally triggered wet-snow avalanches can trigger with increasing frequency in steep terrain as the day unfolds. On steep grass-covered slopes, glide-snow avalanches are possible, ordinarly “announced” prior to release by open glide cracks in the snowpack surface. Beyond that, on shady high-altitude slopes are also avalanche prone locations in the form of older snowdrifts where a slab avalanche can be triggered, primarily by large additional loading of the snowpack. Due to daytime warming combined with intensive solar radiation, the firmness which the snowpack gains during nights of clear skies (through outgoing longwave radiation) is then forfeited swiftly during the daytime. The snowpack becomes moist or wet and thereby loses its stability. Naturally triggered wet-snow avalanches and glide-snow avalanches (due to a slippery ground-level film on grassy slopes) can trigger as a result. In shady high-alpine terrain, in addition, there is a so-called old-snow problem: in this case it is the older snowdrifts which are still prone to triggering. Tuesday skies will have isolated cloudbanks, but be generally sunny during the morning hours. Winds will slacken off, including in the eastern mountain ranges, subsequently be blowing only at light to moderate strength from northerly directions. Temperature at 1500 m at midday: +10 degrees; at 2000 m, +6 degrees, everything at mild springtime level. The high-pressure influence continues to provide us with very mild, sunny weather in Styria. On Wednesday, midday temperatures of +13 degrees at 1500m; +9 degrees at 2000 m, amid light to moderate winds. The firmness which is regained during the nocturnal hours is rapidly lost in the daytime, thereby generating the ongoing daytime cycle of avalanche danger. 2021-03-29T16:00:00+00:00 avalanche-warnings.eu 2021-03-29T22:00:00+00:00 2021-03-30T22:00:00+00:00 2021-03-29T22:00:00+00:00 2021-03-30T10:00:00+00:00 1 2021-03-30T10:00:00+00:00 2021-03-30T22:00:00+00:00 2 2021-03-29T22:00:00+00:00 2021-03-30T10:00:00+00:00 1 2021-03-30T10:00:00+00:00 2021-03-30T22:00:00+00:00 1 wet snow daytime cycle of naturally triggered avalanches Avalanche danger will increase to moderate during the day Avalanche danger increases to moderate during the course of the day at higher altitudes which still have ample snow depths. Through a combination of daytime warmth and solar radiation, naturally triggered wet-snow avalanches can trigger in steep terrain as the day unfolds. The firmness regained during the nocturnal hours (through outgoing longwave radiation) is swiftly lost during the daytime as the snowpack surface becomes moist or wet. Through this destabilisation, naturally triggered wet-snow avalanches or (depending on the ground-level film on steep grassy slopes) glide-snow avalanches become possible. In general, there is little snow at these altitudes and the slopes are becoming ever more bare as the mild springtime weather progresses. Tuesday skies will have isolated cloudbanks, but be generally sunny during the morning hours. Winds will slacken off, including in the eastern mountain ranges, subsequently be blowing only at light to moderate strength from northerly directions. Temperature at 1500 m at midday: +10 degrees; at 2000 m, +6 degrees, everything at mild springtime level. The high-pressure influence continues to provide us with very mild, sunny weather in Styria. On Wednesday, midday temperatures: +13 degrees at 1500m; +9 degrees at 2000 m, amid light to moderate winds. The firmness which is regained during the nocturnal hours is rapidly lost in the daytime, thereby generating the ongoing daytime cycle of avalanche danger.