2011-12-08T09:16:00+01:00 Patrick Nairz 2011-12-08+01:00 https://lawine.tirol.gv.at/data/fotos/DELETED.jpg Information on the avalanche situation will next be published at the next heavy bout of precipitation. Full depth snowslides on steep, grassy slopes. Fresh snowdrift in high alpine regions. Weather in general: Tirol continues to be in the path of a powerful air current coming from the west or southwest over the next few days, which bears a series of disturbances in store. Today, a weak intermediate high pressure zone prevails. Mountain weather today: the storm strength winds will slacken off, even in the mountains, but will remain strong. Visibility will improve during the morning hours, by this afternoon the peaks will be bathed in sunshine. In the course of the day at all altitudes, temperatures are expected to rise. Temperature at 2000 m: minus 5 degrees; at 3000 m: minus 11 degrees. This morning, westerly to northwesterly winds will remain stormy in places, this afternoon reducing slightly to strong velocity in the Northern Alps, elsewhere slacken off to moderate velocity. Trend for coming days: highly variable conditions with occasional light showers. Over the last 24 hours, there has been additional snowfall, this time throughout the land. In most cases, there was 20 to 40 cm of fresh fallen snow. Strong northerly winds transported the new fallen snow intensively, creating huge masses of fresh snowdrift above the treeline. As a potential bed surface for these snowdrift masses, a thin, faceted layer of old snow left over from autumnal snowfall is the likeliest candidate; it forms a cohesive, surface-wide body most often in glacial terrain. Otherwise, in some very steep areas near ridge lines above approximately 2000 m where fresh snowdrift has been deposited atop cold, loosely packed new fallen snow, the snow masses will also be trigger sensitive for a short time. Winter has now returned throughout the countryside. That means our sights need to be re-set to prepare for avalanche perils. Currently, the greatest caution is demanded on very steep, grassy slopes, where the new fallen snow can be unleashed in the form of full depth snowslides. This type of avalanche usually forewarns imminent danger through fissures in the snowpack, making it relatively easy to spot the peril. However, the moment when the avalanche will trigger is unpredictable. For that reason, areas beneath such glide cracks should be decisively avoided. In addition, above the treeline, very prominent masses of snowdrift have formed afresh, and their prevalence increases with ascending altitude. In eastern to southern to southwestern expositions, in very steep terrain adjacent to ridge lines above approximately 2000 m, such snowdrift accumulations can be triggered especially easily. In northern expositions, this trigger sensitivity applies generally to terrain above approximately 2600 m, with glaciated areas being particularly hazardous. There, slab avalanches can be triggered even by minor additional loading, e.g. by one single skier. One unusual aspect of this winter is that particularly in shady terrain, the fresh fallen snow has often been deposited atop large sized ice sheets which formed over the extended periods of sunny, dry weather in late autumn. Apart from the hazards of falling, small sized avalanches can also be unleashed from such spots.