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Weak facets about a foot above the ground are the weakest and easiest to find in steep, rocky, avalanche starting zones. It is tricky because they do not appear to be a problem in the snowpack in meadows and other safe areas to dig snowpits. This means we can easily get false indications of stability. We used a rope to safely dig in this location. Photo: GNFAC

On January 17, 2014 a snowmobiler triggered a slide outside Cooke City on a northeast facing slope at 9,700 feet at the northern end of Henderson Ridge near Chimney Rock.  The slide was approximately 500 feet wide, 300 feet vertical and broke 4-12 feet deep. The slope angles at the crown measured 36-50 degrees and the runout angle was 22 degrees. It was a large avalanche for this slope (HS-AM-O-R4-D3). The rider was buried, dug up, given CPR, revived and he rode away on his own sled. He and his machine were located on the right edge of the debris.

From an email: "We observed this snowmobile triggered avalanche minutes after it occurred on Southern Aspect of Miller's Ridge in Sheep Cree Basin (Cooke)." Four sledders were highmarking and triggered this avalanche on Saturday, January, 18.  Photo: B. Norrgard

This surface hoar crystal is huge!  It was found in Teepee Basin.  We are findine surface hoar deposits and other facets forming at the snow surface.  These may be our next avalanche problem when they get buried.  Photo: J. Mom