Detailed Accident Report
Submitted By: AAA
Place: Snoqualmie Pass, Granite Mountain, south side
Summary: 1 backcountry skier caught, buried and killed
From the NWAC's Monday morning (3/24) report: Around 4:45 PM on Saturday afternoon 2 skiers and a dog descending the looker's left (or skier's right) avalanche path on the south side of Granite Mt (visible from I-90) triggered a slab avalanche that stepped down to a deeper slab. Upon review of crown photos (below) and conversations with local avalanche professionals from Snoqualmie Pass it seems most likely that the initial slab failure on this cross loaded path included the Wed/Thu storm snow and the second slab of similar depth included last Sun/Mon storm snow with the bonds between these layers weakened by strong solar input and potential melt water in the upper snowpack during the afternoon. The best estimate right now is that both slabs were at least 1 foot in depth.
The skier caught and eventually killed in the slide left the ridgeline at about 5200 ft in elevation and skied onto a steep (40+ degrees) slope. The avalanche became a large and destructive wet slab funneling down to around 2300', entraining increasingly saturated snow lower in the avalanche path and at times gouging to the ground. Initial size estimates are at least D3/R3. The other person was in a safe zone and not affected. The skier who was caught was buried under 20 feet of debris but was recovered Sunday morning by local search and rescue efforts. Another party of two lower on Granite was not caught and aided in the preliminary search efforts.
We don't believe the upper snowpack structure that led to this accident is common throughout the west slopes. However, we are increasingly concerned about wet snow avalanches on Monday, including those in isolated areas that could lead to wet slab avalanches.
Posted 24 March 2014 at 0900 MDT