Assess start zones carefully for signs of storm or wind slabs at higher elevations.
Confidence
High - Due to the number and quality of field observations
Weather Forecast
SUNDAY: Cloudy with isolated flurries, light winds, alpine temperatures around -5.MONDAY: Cloudy with isolated flurries, light winds, alpine temperatures around -7.TUESDAY: Cloudy with sunny periods, light winds, alpine temperatures around -10.
Avalanche Summary
No new avalanches were reported on Saturday. On Friday, explosive control produced several size 1.5-2.5 storm slabs on north and east alpine slopes. Human triggering avalanches in the storm snow may remain possible at higher elevations.
Snowpack Summary
A warm wet storm delivered 20-40 cm of heavy snow on Thursday with freezing levels up to 1600 m. Storm slabs exist at higher elevations, particularly on wind-loaded northeast slopes. Crusts near the surface can be found on solar aspects at high elevations and on all aspects below 1600 m. The lower snowpack appears to be well settled. There have been isolated reports of surface hoar layers that formed in early January that may still exist about 40 cm deep in sheltered areas.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.