Beginning of an avalanche cycle.
12th February 2024
At least seven dry natural avalanches in the environs of Coire Ardair today. Persistent drifting throughout the morning built weak windslab high on most N to E facing lee slopes and gullies. With more snow and wind in prospect overnight and throughout Tuesday, instability is expected to become a little more widespread on lee slopes.
I think all today’s events were new snow avalanches – avalanches that occur during or immediately after snowfall or drifting – and unrelated to the complicated pattern of buried weak layers that seemed to have affected our area recently. It’s entirely possible these persistent weaknesses will become reactive once buried by a relatively heavy overburden of newly drifted snow. We shall see.
If you read the avalanche forecast carefully you’ll see the phrase, ‘Avalanches are likely’ which indicates that we think avalanches will (again) be naturally occurring, being triggered simply by the sustained build up of drifted snow and not by other triggers such as cornice collapse. It’s indicative of very poor stability.
(Below) A sequence of two shots of a dry slab avalanche in the Inner Coire that went airborne down the course of both ‘The Wand’ and ‘Diadem’ at 11.02am today.
(Above) Recent (this morning) avalanche debris below Bellevue Buttress in Coire Ardair. The large chunk of cornice is a relic of a cornice collapse about a week ago and is now a snow-ice ‘boulder’.
(Above) The snowladen rock ledges on the NNE-facing crags in the Inner Coire. Recently covered with a deepening overburden of snow and quite possibly with buried weak layers lurking there.
(Above) Quite bright between the showers. Looking over to Bellevue Buttress and the Pinnacle.
(Above) The Inner Coire. Looking up towards the windslab-laden approach to The Window.
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