{ "bulletins": [ { "regions": [ { "regionID": "AT-05-18" }, { "regionID": "AT-05-17" }, { "regionID": "AT-05-16" }, { "regionID": "AT-05-08" }, { "regionID": "AT-05-04" }, { "regionID": "AT-05-05" }, { "regionID": "AT-05-15" }, { "regionID": "AT-05-09" }, { "regionID": "AT-05-10" }, { "regionID": "AT-05-11" }, { "regionID": "AT-05-07" }, { "regionID": "AT-05-06" } ], "validTime": { "startTime": "2021-04-20T22:00:00+00:00", "endTime": "2021-04-21T22:00:00+00:00" }, "source": {}, "dangerRatings": [ { "elevation": {}, "customData": [], "mainValue": "moderate" } ], "avalancheProblems": [ { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "S", "SW", "W", "NW" ] }, "problemType": "wet_snow", "comment": "Daytime cycle of naturally triggered avalanches, on sunny slopes up to 2400m" }, { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "W", "NW" ] }, "problemType": "persistent_weak_layers", "comment": "above 2000m, triggerable in transitions from shallow to deeper snow" } ], "tendency": { "validTime": {}, "tendencyComment": "On Thursday, delayed cycle of naturally triggered avalanche activity due to cloud cover and lower temperatures. And danger of small-to-medium wet-snow avalanches due to rainfall up to intermediate altitudes." }, "bulletinID": "RID910RGR1", "publicationTime": "2021-04-20T16:00:00+00:00", "avalancheActivityHighlights": "Naturally triggered avalanches more frequent starting in mid-morning", "wxSynopsisComment": "Following a night of clear skies, Wednesday will begin with brilliant sunshine and outstanding visibility. As of midday, convective cloud build-up will intensify, peaks and high alpine terrain will disappear in fog. Rain showers are possible in isolated cases, snowfall above 1600-2000m. Light to moderate W/NW winds. Temperatures at 2000 m: from -2 to +3 degrees; at 3000 m, -7 degrees.On Thursday following a night of clear skies, sunshine and clouds will alternate accompanied by showers, snowfall level 1400-1800m. Amid strong NW winds, temperatures on the northern flank of the Alps will drop somewhat.", "avalancheActivityComment": "Avalanche danger will rise to MODERATE already during the morning.\r\nWet-snow problem: numerous small-to-medium (isolated large-sized) naturally triggered wet loose-snow avalanches in very-steep to extremely-steep terrain, on sunny slopes up to 2400m. Wherever it snowed last week, isolated medium-sized glide-snow avalanches are possible on slopes which were previously bare.\r\nDry-snow avalanches: above 2200m in isolated spots in extremely steep and ridgeline terrain where a medium-to-large dry-snow slab avalanche can be triggered (old-snow problem, large additional loading, transitions from shallow to deeper snow). In steep ridgeline terrain at high altitude, in addition, caution urged toards fresh, thin snowdrifts: danger of falling.", "snowpackStructureComment": "Atop a well settled old snowpack there has been 10-20 cm of fresh snow deposited over widespread areas, which up to intermediate altitudes is moistened. Thin, superficial crusts on sunny slopes soften rapidly in the daytime due to solar radiation, and the snowpack moistening process continues. On very steep grass-covered slopes the snowpack can glide across the ground. Potential fracture points for slab avalanches exist only in isolated cases in the uppermost melt-freeze crusts of the old snowpack above 2000 m. In exposed high-alpine ridgeline terrain there are thin snowdrift patches generated by strong N/W winds." }, { "regions": [ { "regionID": "AT-05-20" }, { "regionID": "AT-05-19" }, { "regionID": "AT-05-21" }, { "regionID": "AT-05-13" }, { "regionID": "AT-05-14" }, { "regionID": "AT-05-12" } ], "validTime": { "startTime": "2021-04-20T22:00:00+00:00", "endTime": "2021-04-21T22:00:00+00:00" }, "source": {}, "dangerRatings": [ { "elevation": {}, "customData": [], "mainValue": "moderate" } ], "avalancheProblems": [ { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "S", "SW", "W", "NW" ] }, "problemType": "wet_snow", "comment": "Daytime cycle of naturally triggered avalanche activity starting in mid-morning in extended eastern aspects" }, { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "S", "SW", "W", "NW" ] }, "problemType": "gliding_snow", "comment": "in extremely steep grass-covered terrain" } ], "tendency": { "validTime": {}, "tendencyComment": "On Thursday following a night of clear skies, sunshine and clouds will alternate, with some showers (snowfall level 1400-1800m). Strong NW winds will lower temperatures somewhat." }, "bulletinID": "RID910RGR2", "publicationTime": "2021-04-20T16:00:00+00:00", "avalancheActivityHighlights": "Naturally triggered avalanches increasing starting in mid-morning", "wxSynopsisComment": "Following a night of clear skies, Wednesday will begin with brilliant sunshine and outstanding visibility. As of midday, convective cloud build-up will intensify, peaks and high alpine terrain will disappear in fog. Rain showers are possible in isolated cases, snowfall above 1600-2000m. Light to moderate W/NW winds. Temperatures at 1500m, 0 to 7 degrees; at 2000 m: from -2 to +3 degrees.On Thursday following a night of clear skies, sunshine and clouds will alternate accompanied by showers, snowfall level 1400-1800m. Amid strong NW winds, temperatures on the northern flank of the Alps will drop somewhat.", "avalancheActivityComment": "Avalanche danger will increase to MODERATE already in mid-morning\r\nMain danger: numerous small-to-medium naturally triggered wet-snow avalanches in very-steep to extremely-steep terrain up to summit zones. From the Chiemgau Alps to the Gamsfeld Massif, isolated medium-sized glide-snow avalanches are possibe in terrain where the ground was previously bare.", "snowpackStructureComment": "Atop a well settled old snowpack there has been 5-10 cm of fresh snow deposited over widespread areas, which up to intermediate altitudes is moistened. Thin, superficial crusts on sunny slopes soften rapidly in the daytime due to solar radiation, and the snowpack moistening process continues. On very steep grass-covered slopes the snowpack can glide across the ground. " }, { "regions": [ { "regionID": "AT-05-03" }, { "regionID": "AT-05-02" } ], "validTime": { "startTime": "2021-04-20T22:00:00+00:00", "endTime": "2021-04-21T22:00:00+00:00" }, "source": {}, "dangerRatings": [ { "elevation": {}, "customData": [], "mainValue": "moderate" } ], "avalancheProblems": [ { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "S", "SW", "W", "NW" ] }, "problemType": "wet_snow", "comment": "Daytime cycle of naturally triggered avalanches, on sunny slopes up to 2400m" }, { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "S", "SW", "W", "NW" ] }, "problemType": "wind_drifted_snow", "comment": "thin ridgeline snowdrift patches, above 2000 m superficial old-snow problem" } ], "tendency": { "validTime": {}, "tendencyComment": "On Thursday, delayed cycle of naturally triggered avalanche activity due to cloud cover and lower temperatures. And danger of small-to-medium wet-snow avalanches due to rainfall up to intermediate altitudes." }, "bulletinID": "RID910RGR3", "publicationTime": "2021-04-20T16:00:00+00:00", "avalancheActivityHighlights": "Naturally triggered avalanches, danger of falling due to ridgeline snowdrift patches", "wxSynopsisComment": "Following a night of clear skies, Wednesday will begin with brilliant sunshine and outstanding visibility. As of midday, convective cloud build-up will intensify, peaks and high alpine terrain will disappear in fog. Rain showers are possible in isolated cases, snowfall above 1600-2000m. Light to moderate W/NW winds. Temperatures at 2000 m: from -2 to +3 degrees; at 3000 m, -7 degrees.\r\nOn Thursday following a night of clear skies, sunshine and clouds will alternate, with some showers, snowfall level at 1600-2000m. Strong NW winds.", "avalancheActivityComment": "Avalanche danger will rise to MODERATE already in the morning hours.\r\nWet-snow problem: numerous small-to-medium (isolated large-sized) naturally triggered wet loose-snow avalanches in very-steep to extremely-steep terrain, on sunny slopes up to 2400m. \r\nDry-snow avalanches: above 2200m in isolated spots in extremely steep and ridgeline terrain where a medium-to-large dry-snow slab avalanche can be triggered (old-snow problem, large additional loading, transitions from shallow to deeper snow). In steep ridgeline terrain at high altitude, in addition, caution urged toards fresh, thin snowdrifts: danger of falling.", "snowpackStructureComment": "Atop a well settled old snowpack there has been 10-20 cm of fresh snow deposited over widespread areas, which up to intermediate altitudes is moistened. Thin, superficial crusts on sunny slopes soften rapidly in the daytime due to solar radiation, and the snowpack moistening process continues. On very steep grass-covered slopes the snowpack can glide across the ground. Potential fracture points for slab avalanches exist only in isolated cases in the uppermost melt-freeze crusts of the old snowpack above 2000 m. In exposed high-alpine ridgeline terrain there are thin snowdrift patches generated by strong N/W winds." }, { "regions": [ { "regionID": "AT-05-01" } ], "validTime": { "startTime": "2021-04-20T22:00:00+00:00", "endTime": "2021-04-21T22:00:00+00:00" }, "source": {}, "dangerRatings": [ { "elevation": {}, "customData": [], "mainValue": "low" } ], "avalancheProblems": [ { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "N", "NE", "E", "SE", "S", "SW", "W", "NW" ] }, "problemType": "wet_snow", "comment": "Wet-snow avalanches during daytime, mostly small" }, { "dangerRating": { "elevation": {}, "customData": [], "aspect": [ "E", "SE", "S", "SW", "W" ] }, "problemType": "persistent_weak_layers", "comment": "Old ridgeline snowdrifts, small, very few spots in extremely-steep terrain" } ], "tendency": { "validTime": {}, "tendencyComment": "No significant change is expected." }, "bulletinID": "RID910RGR4", "publicationTime": "2021-04-20T16:00:00+00:00", "avalancheActivityHighlights": "Isolated avalanche prone locations for slab, small wet-snow avalanches", "wxSynopsisComment": "Following a night of clear skies, Wednesday will begin with brilliant sunshine and outstanding visibility. As of midday, convective cloud build-up will intensify, peaks and high alpine terrain will disappear in fog. Rain showers are possible in isolated cases, snowfall above 1600-2000m. Light to moderate W/NW winds. Temperatures at 2000 m: from -2 to +3 degrees.\r\nOn Thursday following a night of clear skies, sunshine and clouds will alternate, with some showers, snowfall level at 1600-2000m. Strong NW winds.", "avalancheActivityComment": "Danger of avalanches is LOW. In extremely-steep ridgeline terrain there are isolated avalanche prone locations for dry slab avalanches up to medium size. Triggering points are most likely in E-S-W aspects above 2000 m. Triggering generally requires large additional loading. Transitions from shallow to deep snow (or vice versa) are particularly treacherous. On sun-drenched slopes, superficial wet-snow avalanches are possible, mostly small-sized.", "snowpackStructureComment": "Compact surfaces dominate, often breakable crustss. Particularly on steep sunny slopes the snow softens up during the daytime. Bonding to the compact old snowpack is generally good. Near ridgelines there are older, mostly compact snowdrift accumulations generated by northerly winds." } ] }