The following is a press release from the Flathead Avalanche Center:
A skier triggered avalanche was reported to the Flathead Avalanche Center (FAC) Saturday evening (12/14). FAC staff was able to speak with the skier who triggered the avalanche and was subsequently caught in the avalanche that evening. The location was just skier’s left (south) of Picnic Notch and north of Crown Bowl in the Swan Range. The skier triggered the avalanche while ascending the slope after previously descending the slope. There were two members of the party and only one was caught. The skier was caught and carried approximately 200 vertical feet downslope where he came to rest near a tree, fully buried with just one arm sticking out of the debris. He was able to extricate himself using his free arm and was uninjured.
FAC staff investigated the avalanche site today (12/15). The crown depth of the avalanche averaged approximately 12 inches and the maximum was 16-18 inches. The flanks were difficult to see due to overnight wind loading, but the width of the crown was estimated at approximately 200 feet. Debris ran approximately 500 vertical feet. It appears that the avalanche was triggered in a shallow part of the slope near rocks and propagated along a layer of small facets underneath a wind slab.
The avalanche was preliminarily classified as SS-AS-R4-D2-I. This was a soft slab avalanche unintentionally triggered by a skier.
A full incident report will be published tomorrow (12/16/2013) on the FAC website.