11-12
Recently formed surface hoar (frozen dew) was capped by new snow. This means it will survive and become problematic weak layer once a slab forms on top of it. Surface hoar is often destroyed before it is buried. Unfortunately, it doesn't really matter b/c the snow underneath is very faceted and very weak. It will also make a great weak layer and produce avalanches. We found this situation on all slopes in the Southern Madison Range. Photo: GNFAC
GNFAC Avalanche Advisory for Wed Dec 14, 2011
Snowpack and Avalanche Discussion
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone and mountains around Cooke City:
Potato chip sized crystals of surface hoar at Bacon Rind in the southern Madison Range. We found this from the highway to 9,000 feet. Photo GNFAC
Forecast link: GNFAC Avalanche Advisory for Wed Dec 14, 2011
GNFAC Avalanche Advisory for Tue Dec 13, 2011
Snowpack and Avalanche Discussion
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone and mountains around Cooke City:
Surface Hoar is being found in many locations throughout southwest Montana. This picture was taken up Hyalite. If it does not melt or get blown over before the next snowstorm, it can produce avalanches when buried. Photo: W. Shoutis
GNFAC Avalanche Forecast for Mon Dec 12, 2011
Snowpack and Avalanche Discussion
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone and mountains around Cooke City:
Looking at the 6-10 day forecast, it does not appear that any number of pray for snow parties or burned pair skis will pull us out of this dry pattern. If it’s not going to snow at least we can take a small amount of comfort in the fact it’s not 20 below zero.
GNFAC Avalanche Forecast for Sun Dec 11, 2011
Snowpack and Avalanche Discussion
The Bridger, Gallatin and Madison Ranges, the Lionhead area near West Yellowstone and mountains around Cooke City:
It's been over a week since any measurable amount of snow has fallen over southwest Montana. Since then the snowpack has felt the effects of warm days and cold nights, especially in areas with less than two feet of snow.