Advisory from January 3, 2003
Advisory from January 4, 2003
Avalanche Conditions:
There were 3 more human triggered avalanches in the backcountry yesterday. A group along the Park City ridge line remotely triggered a 2 foot deep, 150’ wide slide in South Monitor. It was adjacent to the slide that Bruce triggered Wednesday, leaving everyone wondering why on earth it didn’t also slide on Wednesday. Also remotely triggered was a smaller, 50’ wide, 2’ deep slide in the Bear Trap gully. And finally, a snowmobiler triggered 100’ wide slide to the ground in the Snake Creek drainage on a slope that had been previously tracked. Resort control work in Little Cottonwood released numerous hard slabs, 100 to 300’ wide, a few with bizarre patterns incidents that seem to happen when surface hoar or facets are the weak layer.
This scary pattern is not changing - most of these slides are failing on a faceted weak layer near the ground, above 9,500’, on slopes steeper than about 35 degrees and most commonly on north, northeast and easterly facing slopes – but there are exceptions to each of these. All this avalanche activity means that the facets have not adjusted to the load of snow they are supporting, and on many slopes all it’s going to take today is a 150 lbs or a hard turn to tip the balance. The only way to be sure of not getting on the wrong side of a ton of snow rocketing down a slope at 60 mph is to travel on low angle slopes, about 30 degrees or less, that are not connected to steeper slopes.
To further complicate the picture, the unusually warm temperatures and direct sun will also add to the instability today, heating up the snow surface. Wet loose sluffs could pull out deeper slabs. Even the shady slopes may heat up if we get some high, thin clouds this afternoon. So when the roller balls start pin wheeling down the slope or the snow gets mushy, it’s time to get off of and out from under steep slopes.
Failed on facets unless otherwise noted.
- South Monitor (Cowboy) remote triggered
- Beartrap (Hardesty) remote triggered
- Snake Creek- already traveled on slope and then it broke to the ground
January 2, 2003
- Cardiff-remote triggered
- No Name Bowl- remote triggered
- Desolation Lake (Gagne) - remote triggered
- 10,420- remote triggered