Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Regions
Cariboos.
Snow, wind and warming are a recipe for elevated danger. Storm and wind slabs will be touchy at treeline and above. Conservative terrain use is essential this week!
Confidence
Low - Intensity of incoming weather systems is uncertain
Weather Forecast
We'll have moderate snowfall amounts through to Monday morning, and then it starts to warm up Monday afternoon. MONDAY: Cloudy with another 10-15cm by morning accompanied by moderate to strong SW winds and freezing levels rising as high as 1500m. TUESDAY: Scattered flurries (3-5cm) with moderate southerly winds. Freezing levels remain near 1600m. WEDNESDAY: Cloudy with another 10-15cm of fresh snow throughout the day accompanied by moderate SW winds. Alpine temperatures hovering around -3 C.
Avalanche Summary
No new reported yesterday. Several Size 1 avalanches were reported Friday on steep solar (south) aspects.On Friday morning, skiers were able to trigger a Size 1.5 storm slab (with good propagation) in a cross loaded slope near a shallow rocky area. Aspect was north/northeast. See here for their great MIN report.
Snowpack Summary
We've had 5-15cm of fresh snow (with moderate southerly winds) each of the past three days, which adds to the 40-80cm of settled storm snow from the past week. Touchy storm slabs can be found at all elevations with weaknesses within and under this recent snow. Recent moderate to strong southerly winds have created touchy wind slabs at treeline and above. All this recent snow is bonding poorly to faceted snow, thin sun crust on steep southerly aspects, as well as surface hoar in sheltered areas in some parts of the region. About 80-120 cm below the surface you'll likely find the mid-February persistent weakness, which is composed of a thick rain crust up to about 1700 m, sun crusts on steep solar aspects, and spotty surface hoar on shaded aspects. Professionals in the region have also warned that a 'threshold load' has been reached above this interface, particularly where it presents as a crust.Some lingering surface hoar weaknesses from January are now down over a metre and the weak mid-December facets are down about 1.5 metres. These deep persistent weaknesses still have the potential to react to human triggers or smaller storm slab avalanches.
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.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.