{ "bulletins": [ { "regions": [ { "regionID": "AT-05-19" }, { "regionID": "AT-05-21" } ], "validTime": { "startTime": "2021-12-16T23:00:00+00:00", "endTime": "2021-12-17T23:00:00+00:00" }, "source": {}, "dangerRatings": [ { "elevation": { "lowerBound": "Treeline" }, "customData": [], "mainValue": "moderate" }, { "elevation": { "upperBound": "Treeline" }, "customData": [], "mainValue": "low" } ], "avalancheProblems": [ { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "NW" ] }, "problemType": "persistent_weak_layers", "comment": "in gullies, steep bowls, behind protruberances, above 1400 m" }, { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "S", "SW", "W", "NW" ] }, "problemType": "gliding_snow", "comment": "extremely steep or seldom used terrain" } ], "tendency": { "validTime": {}, "tendencyComment": "Little change." }, "bulletinID": "RID1139RGR1", "publicationTime": "2021-12-16T17:00:00+00:00", "avalancheActivityHighlights": "Isolated naturally triggered glide-snow avalanches", "wxSynopsisComment": "On Friday, skies will initially be gloomy due to high fog extending up to 1300 m. Starting at midday the high fog can disperse here or there. Milder: at 1500 m: +2 degrees.\r\nOn Saturday above the high fog the visibility will be adequate. The high-fog border will descend, compared to previous days. Winds will be no disturbance. Temperatures will drop slightly, the zero-degree level will lie at about 1500 m.", "avalancheActivityComment": "\r\nThe danger of avalanches above the timberline is MODERATE, below that altitude danger is low. Avalanche prone locations focus on gullies and wind-loaded steep slopes in NW/E/S aspects. Triggering a small-to-medium slab is possible there by large additional loading. In very steep zones, small-to-medium sized glide-snow avalanches can trigger naturally.", "snowpackStructureComment": "The moistened snowpack due to rainfall on Monday has swiftly re-gained firmness and is superficially melt-freeze encrusted, due to nighttime cooling. However, at low altitudes the snowpack is often soft. At higher altitudes of the Gamsfeld Massif, there is a few centimetres of fresh snow deposited atop thin crusts, beneath which faceted crystals have formed in places. On steep, smooth grass-covered slopes the snowpack is currently gliding over the ground. Above the timberline there are compact older snowdrifts in gullies and bowls." }, { "regions": [ { "regionID": "AT-05-17" }, { "regionID": "AT-05-20" }, { "regionID": "AT-05-16" }, { "regionID": "AT-05-14" }, { "regionID": "AT-05-15" }, { "regionID": "AT-05-18" }, { "regionID": "AT-05-13" }, { "regionID": "AT-05-12" }, { "regionID": "AT-05-08" }, { "regionID": "AT-05-04" } ], "validTime": { "startTime": "2021-12-16T23:00:00+00:00", "endTime": "2021-12-17T23:00:00+00:00" }, "source": {}, "dangerRatings": [ { "elevation": { "lowerBound": "Treeline" }, "customData": [], "mainValue": "moderate" }, { "elevation": { "upperBound": "Treeline" }, "customData": [], "mainValue": "low" } ], "avalancheProblems": [ { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "S", "NW" ] }, "problemType": "wind_drifted_snow", "comment": "above the treeline, in gullies and steep bowls, rimlines of snowdrifts are especially treacherous" }, { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "E", "SE", "S", "SW", "W" ] }, "problemType": "gliding_snow", "comment": "in extremely steep grass-covered terrain below 2300 m" } ], "tendency": { "validTime": {}, "tendencyComment": "Little change." }, "bulletinID": "RID1139RGR2", "publicationTime": "2021-12-16T17:00:00+00:00", "avalancheActivityHighlights": "Older snowdrifts in gullies", "wxSynopsisComment": "On Friday, visibility above the valley fog will be adequate. On the Main Tauern Ridge the northerly wind will intensify during the daytime and reach storm strength; in the Northern Alps the wind will disturb only in exposed summmit terrain. At 3000 m: -4 degrees; at 1500 m: +2 degrees.Similar weather conditions to Saturday: on Sunday, good visibility above the high fog. On the Main Ridge, stormy NW winds. At 3000 m: -5 degrees; at 2000 m: -2 degrees.", "avalancheActivityComment": "Danger of avalanches is MODERATE above the timberline, LOW below that altitude. In very steep terrain below 2200 m, isolated naturally triggered glide-snow avalanches up to medium size are possible. Above the treeline there is moderate danger of slab avalanches. Avalanche prone locations focus on gullies in all aspects and wind-loaded steep slopes, increasingly in NW/E/S aspects. Triggering a small-to-medium sized slab avalanche there is possible especially by large additional loading, e.g. by a fall or stamping in the snow.", "snowpackStructureComment": "\r\nWarmth, rainfall (light drizzle up to 2700 m in places) and the subsequent cooling of the snowpack have led to a re-gain in firmness up to intermediate altitudes, the moistened snowpack is now superficially melt-freeze encrusted. The snowpack is gliding over steep, smooth grass-covered slopes over the ground, however, Above the treeline there are older snowdrifts in gullies and bowls which is now blanketed by a few centimetres of settled new snow (at high altitudes of the Tennen Massif and Gosaukamm, up to 10-20 cm). At higher altitudes in wind-protected terrain the loose old snow can serve as a weak layer beneath the lightly bonded fresh snow which has recently been deposited on top of it." }, { "regions": [ { "regionID": "AT-05-06" }, { "regionID": "AT-05-10" }, { "regionID": "AT-05-07" }, { "regionID": "AT-05-09" }, { "regionID": "AT-05-05" }, { "regionID": "AT-05-11" } ], "validTime": { "startTime": "2021-12-16T23:00:00+00:00", "endTime": "2021-12-17T23:00:00+00:00" }, "source": {}, "dangerRatings": [ { "elevation": { "lowerBound": "1800" }, "customData": [], "mainValue": "moderate" }, { "elevation": { "upperBound": "1800" }, "customData": [], "mainValue": "low" } ], "avalancheProblems": [ { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "E", "SE", "S", "SW" ] }, "problemType": "wind_drifted_snow", "comment": "wide-ranging snowdrifts above timberline, in gullies, steep bowls" }, { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "S", "SW", "W", "NW" ] }, "problemType": "gliding_snow", "comment": "glide-snow avalanches on steep grassy slopes below 2300 m" } ], "tendency": { "validTime": {}, "tendencyComment": "Little change on Saturday. Freshly generated trigger-sensitive snowdrifts in high alpine regions remain the main problem. Plus: danger of naturally triggered glide-snow avalanches." }, "bulletinID": "RID1139RGR3", "publicationTime": "2021-12-16T17:00:00+00:00", "avalancheActivityHighlights": "Fresh snowdrifts, esp. in high alpine regions", "wxSynopsisComment": "On Friday, little change. Sunshine above the valley fog. On the Main Tauern Ridge, northerly winds will intensify and become stormy. At 3000 m: -4 degrees; at 1500 m: +2 degrees.\r\nSimilar conditions on Saturday. Strong winds, storm-strength NW winds on the Main Tauern Ridge. Sunny and good visibility. At 3000 m: -5 degrees; at 2000 m: -2 degrees.", "avalancheActivityComment": "Danger of avalanches is MODERATE above 1800 m, LOW below that altitude. In very steep terrain below 2200 m, isolated naturally triggered glide-snow avalanches up to medium size are possible. Above the treeline, avalanche prone locations tend to increase with ascending altitude, due to snowdrift accumulations. Avalanche prone locations focus on gullies in all aspects, especially E/S aspects. Triggering a small-to-medium sized slab avalanche there is possible even by minimum additional loading. Transitions zones from shallow to deeper snow can be treacherous; the weak layers in the old snowpack can be triggered and fracture.", "snowpackStructureComment": "\r\nWarmth, rainfall (light drizzle up to 2700 m in places) and the subsequent cooling of the snowpack have led to a re-gain in firmness up to intermediate altitudes, the moistened snowpack is now superficially melt-freeze encrusted. The snowpack beneath 2300 m is gliding over steep, smooth grass-covered slopes over the ground, however. In high alpine regions, fresh thin snowdrift accumulations ar being generated by NW winds. In exposed zones, wind-crusts dominate. In high alpine regions, particularly on shady slopes above about 2200 m, weak soft layers of faceted crystals are weakening the snowpack fundament." }, { "regions": [ { "regionID": "AT-05-01" }, { "regionID": "AT-05-02" }, { "regionID": "AT-05-03" } ], "validTime": { "startTime": "2021-12-16T23:00:00+00:00", "endTime": "2021-12-17T23:00:00+00:00" }, "source": {}, "dangerRatings": [ { "elevation": { "lowerBound": "1800" }, "customData": [], "mainValue": "moderate" }, { "elevation": { "upperBound": "1800" }, "customData": [], "mainValue": "low" } ], "avalancheProblems": [ { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "E", "SE", "S", "SW", "W" ] }, "problemType": "wind_drifted_snow", "comment": "thin, small-area snowdrift masses behind protruberances, exposed terrain windblown, gullies and bowls lots of snow" }, { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "W", "NW" ] }, "problemType": "persistent_weak_layers", "comment": "in shady terrain above 2300 m, triggerable in transitions from shallow to deeper snow" } ], "tendency": { "validTime": {}, "tendencyComment": "On Saturday, avalanche prone locations due to trigger-sensitive snowdrifts (generated by northerly foehn wind) in expanded southern aspects and in gullies. Depending on the magnitude of the drifts, possible rise in avalanche danger to CONSIDERABLE at high altitudes.\r\n" }, "bulletinID": "RID1139RGR4", "publicationTime": "2021-12-16T17:00:00+00:00", "avalancheActivityHighlights": "Fresh drifts generated by northerly foehn winds", "wxSynopsisComment": "On Friday, increasingly stormy northerly foehn wind (50-70 km/hr) amid mostly sunny weather and good visibility. Temperature at 2000 m: -2 degrees.\r\nAlso on Saturday, sunny and icy-cold northerly foehn wind. Temperatures will barely change.", "avalancheActivityComment": "Danger of avalanches is MODERATE above 1800 m, LOW below that altitude. Avalanche prone locations focus on gullies in all aspects, especially E/S/W aspects. The drifts are still thin, not area-wide, but are prone to triggering. Triggering a small-to-medium sized slab avalanche there is possible even by minimum additional loading in some places. ", "snowpackStructureComment": "Increasingly strong northerly foehn wind starting on Friday, new in high alpine regions. Potential fracture point: faceted crystals below the thin melt-freeze cdrust which formed through the higher temperatures and minor rainfall up to high alpine regions at the beginning of the week. Proneness to triggering of older snowdrift masses from last week in all aspects has diminished. Ground-level soft layers of faceted-crystal riddled layers are weakening the fundament on shady slopes above 2300 m." } ] }