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 unlikely, human triggered possible.
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
South Columbia.
Very strong winds may have left wind slabs in unexpected places. Sweep your gaze further down start zones than normal.
Confidence
Moderate - Timing or intensity of solar radiation is uncertain
Weather Forecast
A building ridge is expected to bring mainly sunny skies with no precipitation for the next three days. A warm southerly flow causes the freezing level to rise as high as 3000 m.For more details check out https://avalanche.ca/weather.
Avalanche Summary
The recent storm snow became more reactive on Friday, with numerous small natural and skier triggered avalanches. In the north of the region, a skier triggered a size 2 wind slab on a north aspect. Although there haven't been any persistent slab avalanches reported recently, it could still be possible to trigger large destructive avalanches in isolated open, unsupported terrain features at and below treeline.
Snowpack Summary
15-40 cm of storm snow is settling to form a soft slab in sheltered areas. Strong southwesterly winds have formed fresh wind slabs in lee features at treeline and in the alpine. Below about 1900 m, a crust may be found about 50 cm below the surface, although this layer seems to be most prevalent in the Monashees. In the far south of the region, a layer of surface buried at the end of January may be found at around this depth in isolated features at treeline and in the alpine. Deeper in the snow pack, the surface hoar layer from early January is now down 80-120 cm in most places. Although this layer has become harder to trigger and is variably reactive in recent snowpack tests, it still has the potential to produce large avalanches. Forecast warming may increase the sensitivity of the persistent slab.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind 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.