Avalanche danger trending up over the next few days due to another warm storm moving in from the Southwest.
Confidence
Fair - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
Cloudy with light snowfall overnight and Thursday morning combined with light Southwest winds and freezing levels at valley bottoms. Southwest winds increasing Thursday night as a pulse of moisture arrives on the South coast. Expect 5-10 cm of new snow by Friday morning. Unsettled with moderate Southerly winds during the day on Friday, expect 3-5 cm of new snow. Southwest winds developing overnight as a strong system approaches the coast, expect 15-20 cm of new snow by Saturday afternoon. Freezing levels are expected to climb up to near 2000 metres elevation.
Avalanche Summary
No new avalanches have been reported.
Snowpack Summary
Current surfaces include a mix of stubborn wind slabs and settled storm snow in the alpine, and a hard rain crust at lower elevations. Surface hoar growth has been reported in sheltered areas. There is still concern for a buried crust/facet layer which formed in November. This woke up with the recent storm snow loading and has the potential for deep slabs and wide propagations. The likelihood of triggering this beast has dropped; however, if an avalanche released at this interface it would be highly destructive.
Problems
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.