09-10
Karl Birkeland checks out the layering in a snowpit at Lionhead in the southern Madison Range. New snow is sitting on large, sugary, faceted grains. This pit was 20 feet uphill from an avalanche that released in the storm. It broke on the new snow and facet interface.
Two very small slides were released as a snowmobile drove by. These insignificant sized slides are indicative of a larger problem: a slab sitting on a weak layer. Tiny slides are Mother Nature's message that bigger slopes are likely unstable too. Don't ignore signs of instability, no matter how small. We had an Avalanche Warning out this day and saw avalanches within a few hundred feet of these.
Forecast link: GNFAC Avalanche Advisory for Tue Dec 15, 2009
GNFAC Avalanche Advisory for Mon Dec 14, 2009
Snowpack and Avalanche Discussion
The southern Gallatin and southern Madison Ranges, the Lionhead Area near West Yellowston, the mountains outside Cooke City and the Washburn Range:
GNFAC Avalanche Forecast for Mon Dec 14, 2009
Snowpack and Avalanche Discussion
Hyalite Avalanche Fatality
An avalanche caught and killed an ice climber in Hyalite Canyon in the northern Gallatin Range of southwest Montana. This avalanche was triggered by a separate party of two climbers above the victim.
GNFAC Avalanche Forecast for Sun Dec 13, 2009
Snowpack and Avalanche Discussion
The southern Gallatin and southern Madison Ranges, the Lionhead Area near West Yellowston, the mountains outside Cooke City and the Washburn Range:
A skier triggered this avalanche on his way back to the Mt. Blackmore trailhead. It broke on a NE facing, 38 degree slope. The skier was able to stop himself before getting strained through trees lower on the slope. The avalanche was 1.5 feet deep, 90 feet wide and ran for a few hundred feet.
Mark Staples triggered this small slide near Sunlight Basin in Taylor Fork yesterday (Dec 12). Wind blown snow was failing on a layer of facets.
GNFAC Avalanche Advisory for Sun Dec 13, 2009
Snowpack and Avalanche Discussion