Cold and Crisp to End 2022

31st December 2022

It was a nice cold clear crisp day to end 2022. The snowpack today very much showed the effects of yesterdays weather. During yesterday afternoon the freezing level briefly rose to around the level of the highest summits, possibly accompanied by some freezing rain. The wind also rose significantly. With the return to colder conditions today, the snowpack had formed a hard and icy crust.  There had been a dusting of fresh snow, but deposits were very shallow. Above 1000 metres there was evidence of significant wind redistribution of the snowpack (sastrugi). The combination of wind redistribution and rising temperatures produced a period of instability yesterday afternoon. I saw evidence of a with a number of small to medium sized avalanches which occurred in Coire an Lochan during this period. It looked like many of these had be triggered by collapsing cornices.

Sastrugi (wind eroded snow) indicating wind redistribution of the snowpack had occurred. 

Coire an Lochan of Aonach Mor. Two small crown wall can be seen, one at the back of the gully on the right, and the other just below the crest in the middle distance. These likely occurred yesterday afternoon and looked to be cornice triggered. The previous picture (of the sastrugi) was taken by the posts visible in the middle distance. The the snow eroded from that location would have been deposited in, or just below the cornice, and thus would likely have been involved in these avalanches. 

The top of Easy Gully. Not the best light but two crown wall can be seen, one cutting up diagonally right, the other cutting up diagonally left. These likely occurred yesterday afternoon during the during a slightly milder spell. 

The view over to Carn Dearg and Ben Nevis from the summit of Aonach Mor. 

The view South to Aonach Beag. 

 

Comments on this post

Got something to say? Leave a comment

    Latest Lochaber Avalanche Report
    Archives
    Categories
    RSS Feed
    Keep up to date by subscribing to our RSS feed
Service funded by sportscotland
Forecast data supplied by the Met Office
SAIS Sponsors