Confidence
Fair - Forecast snowfall amounts are uncertain
Weather Forecast
A series of waves of Pacific moisture continue to bring precipitation into the interior of BC. Forecast models vary on the timing and intensity of the incoming storms, some locations may see large amounts of precipitation. Southern parts of the forecast area may see warmer temperatures than the north.Friday night: Freezing level around 700m; A wave of Pacific moisture will bring more snow to the region, light to locally moderate amounts of precipitation with continuing strong south west winds at ridge top.Saturday: Freezing level around 1000m; A bit of a break in the weather early on Saturday. Precipitation beginning in the early afternoon and into Sunday, some areas may receive up to 10 cm. Light winds from the south east at ridge top.Sunday: Freezing level at valley bottom; More Pacific moisture with 10 to 20cm in the precipitation forecast. Winds are forecast to be strong at ridge tops.Monday: Freezing level around 9000m; Continued precipitation from Sundays storm and another 5 to 10 cm. Wind calm down a bit, and forecast to be moderate to strong at ridge tops
Avalanche Summary
Reports of numerous size 1 to 2 skier controlled and natural avalanches up to size 2.5 in the past 24 hrs. We expect the number of reported avalanches to increase with the snow loading and strong upper elevation winds.
Snowpack Summary
In recent days many parts of the forecast area have received up to 90cm of snowfall. The combination of new snow, wind and moderate temperature have formed a cohesive and reactive storm slab with deeper, more destructive deposits developing in exposed lee terrain. Significant cornice development is expected to have occurred as well.Below the new snow is a mixed bag of surface hoar, facetted snow and other hard surfaces which formed during the previous cold clear weather. The bond between the new storm slab and these buried surfaces is weak with professional accounts of very easy snowpack test results and widespread destructive avalanche activity. Due to the persistent nature of these buried weaknesses, touchy conditions are likely to exist for some time.For the most part, the mid and lower snowpack are strong and well consolidated. Although basal facets are likely to exist in some areas, triggering has now become unlikely.
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.