Winter conditions in the mountains, including possible avalanche danger

Highly variable weather conditions have brought some fresh snow to the mountains since the end of October. The snowfall was particularly heavy during the last few days. The amounts of fresh fallen snow in the regions along the Main Alpine Ridge and southwards therefrom were frequently about 50 cm, significantly more from place to place.

Tux Valley  (Photo: 06.11.2019)

Fresh snow on Stubai Glacier (Photo: 05.11.2019)

 In the interim, the first reports of avalanches have reached us:

27.10.2019: Naturally triggered slab avalanche near the summit of the Ortler
01.11.2019: Slab avalanche in the north face of the Hochferner, which triggered when mountaineers were there. Fracture depth: max. 10 cm.
04.11.2019: Naturally triggered slab avalanche in the Hochfeiler north face. Triggered during snowfall accompanied by wind.
05.11.2019: Successful artificial triggerings with explosives on Pitztal Glacier, including naturally triggered slab avalanches.

Naturally triggered slab avalanches: Hochfeiler north face (Photo: 04.11.2019)

Shady, very steep high alpine terrain (above 3000 m) was struck with particular vehemence recently. Indications point to the beginning of an old-snow problem. We assume that near the melt-freeze / rain crusts a weak layer of faceted crystals has formed. Rainfall on 21 October up to over 3300 m may have been the cause.

Furthermore, the first autumnal snowfall, which was limited to the high alpine zones, also played a part (first time on 8 September).

Review of last month: in October some precipitation with mostly sunny, unseasonably warm phases. As of the end of October, increasing precipitation. The arrow indicates each day when it rained up to over 3300 m.

The situation reminds us of autumn 2016, when the first avalanches of the season took place already in mid-October (Olperer, Hochferner)

Upshot: In high alpine regions the winter has already begun, avalanches are possible as of now. Winter sports fans can trigger slab avalanches even by minimum additional loading, particularly in the indicated aspects and altitudes.

At lower altitudes where there has been ample snowfall and the ground surface is smooth (especially steep grass-covered slopes), increasingly frequent glide-snow avalanches can be expected.

Please note: data of snowpack analysis and observations are still lacking. Thus, an area-wide assessment of avalanche danger is not yet possible.

What’s next?

To start with, tranquil weather conditions will arrive on Thursday. In the evening, a low over Genoa will launch some rainfall and snowfall from the southwest. By Friday morning, the precipitation will spread throughout the Main Alpine Ridge and regions to the south of it. In North Tirol, it will generally remain dry Thursday night, rainfall and snowfall will be launched on Friday. Focal point of the precipitation will clearly be the southern and eastern parts of the Europa Region. This round of precipitation will be accompanied by storm-strength southerly-to-southeasterly winds in places. On Friday night, conditions will quiet down incrementally. On Saturday morning, only isolated rainfall and snowfall are anticipated.

Total precipitation (24 hrs) in mm of the European weather model for all day Friday.

The snowfall level will be at 1000 m on Friday, in some places even lower. According to the latest weather model, the snowfall level will ascend significantly in the Dolomites during the course of the day. The prospective amounts of fresh snow are visible on the map below: 

Fresh snow forecast from Wednesday through Saturday, with settling snow.

The model for fresh snow forecasts will be updated twice daily on our website, so we recommend keeping up to date by consulting this link: https://avalanche.report/weather/map/fresh_snow

Avalanche danger will increase significantly as of this snowfall, particularly in the regions where there is a great deal of fresh snow, in high alpine zones and generally wherever the fresh fallen snow is deposited on top of an old snowpack. On steep grass-covered slopes, glide-snow avalanches can be expected, in high alpine regions naturally triggered or easily-triggered slab avalanches are anticipated. For the weekend, the avalanches risks should not be underestimated.

The next update of the avalanche situation will be published whenever the situation changes significantly.