Quick report
- Cracking
- specific
- Collapsing
- isolated
Multiple test slopes produced D1 wind slab avalanches near treeline on leeward, easterly and southerly aspects. We observed cracking prior to all these slides releasing. Along the corniced ridge of Sun Bowl we noted a single collapse.
Weather
- Air Temp
- 20-25
- Cloud Cover
- obscured
- Wind Loading
- moderate
- Rain Elevation
- 5,000
- Recent Snowfall
- 30
- Snow Avail For Transport
- small smounts
The last bit of precipitation of this passing storm lingered through the night into this afternoon, bringing about two inches of new snow to below and near treeline elevations. Skies were, for the most part, obscured by clouds and snowfall. There were a few brief periods of improved visibility, but the sun never truly broke through the clouds. Temperatures near treeline ranged from 20 to 25°F with light to moderate WNW wind.
Snowpack
The wind slab problem is still active above treeline on Mount Shasta. Test slopes demonstrated easily triggered wind slabs, and recent avalanches nearby confirmed the problem's prevalence. Slabs ranged in depth from 6 inches at the thinnest to nearly two feet at the deepest. With Sun Bowl being one of our most popular zones, it can be easy for folks to fall into the familiarity heuristic trap and mistakenly deem themselves as safe. What today's observations and recent avalanche activity tell us is that recreationalists should express caution on and near wind loaded, steep slopes, especially above treeline. As precipitation exits the region, this wind slab problem will begin to heal over the coming days. For now, play it safe folks.
Avalanche
- Size
- D1.5 R1
- Type
- SS
- Aspect
- SE
- Trigger
- N
- Elevation
- 8500 ft
The weight of a skier near the treeline easily triggered wind slabs up to 44 centimeters (1.5 feet) deep on leeward, southeast aspects.