|Eight Snowmobilers Dead in Avalanche Near Fernie #2122|
Back To Discussion List Written: 2008.12.29 by: Frank W. Baumann
See the following link to the CBC story:
The CAA South Rockies Bulletin has been warning for days now about the dangerous presence of a weak buried facet layer created by the long December cold spell.
Starting just before Christmas, that persistent weak layer (PWL) became buried by more and more new snow, often brought in with high winds- the perfect recipe for a disastrous avalanche cycle.
Unfortunately this type of situation is difficult to report given our present Avalanche Danger Scale- which is hazard-based. A hazard-based system only reports the probability of avalanching, and does not adequately report a situation, as existed here, where the snowpack was trigger-ready to slide, even though overall, not many avalanches were occurring. In this case, the CAA Avalanche Danger Rating issued on Saturday, December 27, 2008 (the last forecast issued before the accident) for the South Rockies was only CONSIDERABLE. But the text-based portion of the forecast was warning of the presence of the Persistent Weak Layer, and even reported on one large Size 3 avalanche that had occurred. Given the dangerous early winter conditions, this could be a very bad year for avalanches so please take the time to read up on avalanches here on Bivouac. A good place to start is the article on Persistent Weak Layers (PWL's) in the reference section.
#1131 - 2008.12.29 Scott Nelson - Dec 27th CAC Forecast Spooky isn't it. From what I've read in the newspapers this pretty much describes what happened in the accident.
"Be especially careful at this time to avoid exposure to avalanche slopes from above, particularly when grouping up."
Spooky isn't it. From what I've read in the newspapers this pretty much describes what happened in the accident.