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Report
Sun. 21.01.2018
update today 7:30 (Bernhard Niedermoser - translated by Jeffrey McCabe)

Danger increasing further, will reach HIGH with storm, also naturally triggered avalanches

Afternoon

Morning

Fresh snow by evening (20-40 cm, 50 cm in barrier cloud regions), zero visibility and from midday storm winds above 1800 m. New drifts and those of Friday trigger-sensitive. On many steep slopes in all aspects, near to and distant from ridgelines, one person can trigger an avalanche. In heavily wind-loaded zones (NE to S) above 2000 m isolated larged-sized releases can trigger naturally.

Avalanche Danger

Avalanche danger in the Northern Alps above 2000 m is HIGH (4) right from the start today. In the other mountain ranges it is initially CONSIDERABLE (3) but will increase to HIGH (4) as of midday. In the Lungau Nockberge, danger will remain CONSIDERABLE (3).

In the Lungau Nockberge the danger zones focus on gullies and bowls in all aspects. The remaining terrain is much windblown.

In the other mountain ranges the situation is critical or soon will become critical as a result of storm winds. The snowdrift accumulations which will form can be triggered in all aspects above the treeline by the weight of one sole person. Moreover, visibility is zero.

Naturally triggered avalanches: NW winds are transporting the snow massively, both fresh and snowfall from Friday. In leeward zones (east and south) snowdrift accumulations are massive and deep. Naturally triggered avalanches can discharge. Numerous medium-sized, in isolated cases also large-sized releases from high altitude avalanche starting zones are possible, particularly in the Northern Alps. Isolated gliding avalanches also continue to be possible on extremely steep, grass-covered slopes below 2100 m. These could have huge fracture breadths.

Snow Layering

Yesterday, Saturday, wide ranging snowdrift accumulations which have formed since Tuesday settled somewhat, their trigger-sensitivity diminished slightly. However, during the night in the Hohe Tauern, foehn wind raged. With the arrival of a cold front, winds this morning shifted to northwesterly and an additional 25-50 cm of fresh snow will still be added to it. As of about midday, storm-strength winds will set in, which will massively transport the entire fresh snow which has fallen since Friday.

The trigger sensitivity of the snowdrifts varies. Today’s drifts and those formed on Friday are quite prone to triggering. Those from Wednesday and Thursday, less so. The most threatening potential fracture points are currently found in transitions from drifted zones and in blanketed loosely-packed powder. More deeply embedded fracture points are found at the borderline to the old snow.

The old snowpack beneath this is stable. However, the ground-level layers are drawing moisture from the warm ground. This keeps the danger of gliding avalanches alive.

Alpine Weather Forecast (ZAMG Salzburg)

Today, Sunday, dense fog. Winds to begin with will be moderate, as of midday will intensify to storm strength above the treeline (80-100 km/hr) accompanied by heavy snowfall from the north. Overall, 25-50 cm of fresh snow is anticipated in the Northern Alps in the next 24 hours. Temperatures will drop: at 2000 m from -9 to -13 degrees.

Tomorrow, Monday, the peaks will be hidden in dense cloud, snowfall will persist. About 15-30 cm of fresh snow is anticipated. Strong W/NW winds (40 km/hr). At 2000 m temperatures will rise from -7 to -1 degree; at 3000 m from -10 to -7 degrees.

Short Term Development

On Monday/Tuesday a warm front will arrive. Strong warming impulses are expected. Plus, compacted fresh snow will be deposited atop the loosely-packed, cold snowfall of today. It will be highly prone to triggering (naturally triggered avalanches!). On Monday, in all likelihood, HIGH AVALANCHE DANGER over widespread areas. As of mid-week, conditions will be stabler.





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