Poor vis, soft slab & developing cornices.
4th January 2026
Cold and wintry today again with persistent light snow showers throughout the morning meant poor visibility above 600m and a full-on ‘white room’ experience above 800m.
We have an ongoing windslab problem and a developing cornice problem at Creag Meagaidh. The soft slab has several weaknesses within it however crack propogation is modest. Had the windslab been significantly firmer the formal avalanche hazard level would have been elevated to Considerable since stiffer slabs – in the event of weak layer failure – mean longer crownwalls. In general, soft windslab = comparatively smaller avalanches.
Potential triggers for soft slab avalanches at the moment would be: additional loading due to drifting (which we’re expecting overnight), humans, and cornice collapse. The cornices on our patch are surprisingly modest but they’re soft (aka weak) and likely to grow a bit and become weaker over the course of the forecast period.
So. Noticeably deeper soft windslab is present on our lee slopes (check the ‘Meggie forecast for exact details) above 900m and this is also where the developing cornices are also hanging out (pun intended). Not a great combo.
Access up the track was OK today but skis or snow shoes would be best option if venturing away from it. Skiing conditions are somewhat compromised by a preponderance of partially exposed heather. Skinning up hill is OK but only the best exponents of combat skiing are likely to get (any?) satisfaction out of the descents. I measured 18cm of undrifted snow at Aberarder farmhouse this afternoon but wind meant there had been cheek-by-jowl scouring and drifting in the usual Scottish way at higher altitudes.
(Above) Minor build up of drifted snow across the main Coire Ardair path this morning. Elsewhere, the path was OK for foot traffic and skis would definitely have worked well too.
(Above) A view towards the crags of the Post Face at the top end of Coire Ardair from high in Coire Chriochairein. Above this altitude visibility declined to a few dozen metres for the whole morning.
(Above) 12.30pm. The steeper part of the main Coire Ardair just above Aberarder. Some brief but welcome sunshine.
(Above) The East-facing side of Sron a Ghoire. Centre summit at 830m The broad NE shoulder over on the right quite often has well-developed accumulations of windslab when we have snowfall/drifting and the winds come from anywhere with West on it. Not today. We can get slab avalanche activity from this shoulder, anywhere from 550m (starting at the birch treeline, extreme right) up to 750m. Also the site of a massive full depth avalanche in 1994 (or ’95?). The brightly lit windslab to the left of the 830m summit – leading down to the col – will get a visit tomorrow.
(Above) Coire Dubh, a SE-facing coire viewed from the A86 this afternoon. Note the cornice line, small but expected to grow a little overnight.
(Above) Coire nan Gall, E and SE-facing, very close to Coire Dubh and part of the Carn Liath massif.
(Above) The Big Picture this afternoon. Puist Coire Ardair, Sron a Ghoire and in the distance the crags of the Post Face of Coire Ardair all looking quite wintry.
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