Fresh storm and wind slabs are likely deeper and more widespread in the norther part of the region. Deeper persistent weaknesses maintain low probability but high consequence conditions.
Summary
Confidence
Moderate - Wind effect is extremely variable
Weather Forecast
THURSDAY: Mainly sunny with light northeasterly winds. Freezing levels in valley bottoms with alpine temperatures reaching -15 C.FRIDAY: Increasing cloudiness with light snow flurries starting in overnight. Light but gusty southwesterly winds and freezing levels remaining in valley bottoms with alpine temperatures reaching -10 C.SATURDAY: Cloudy with light flurries and light but gusty southwesterly winds. Freezing levels remaining in valley bottoms with alpine temperatures reaching -10 C.
Avalanche Summary
On Monday, several natural wind slab and storm slab avalanches up to size 2.5 were reported. These slabs were typically 30-50 cm thick and failed on a variety of aspects at treeline and in the alpine. Skiers also triggered several size 1 slabs. Fresh wind slabs are expected to remain sensitive to human triggering, especially on steep and unsupported (convex) slopes. Winds have recently switched from south to north and wind slabs should be expected on all aspects in exposed terrain.Persistent slab avalanches also remain a serious concern for the region. Last week there were numerous large human triggered avalanches and several of these avalanches involved multiple people being buried. These avalanches all released on or stepped down to the mid-December persistent weakness down 1-1.5 m in the snowpack.
Check out this list of recent near misses which includes many in the Cariboo region.Snowpack Summary
10-60 cm of recent snow (with the largest amounts in northern parts of the region) and strong shifting winds have resulted in fresh wind slabs on a variety of aspects in wind exposed terrain. The persistent weakness buried mid-January is now down 50-100 cm and consists of buried surface hoar in sheltered areas, and/or widespread faceted old snow. It has generally stabilized but may remain sensitive to triggers in isolated areas where buried surface hoar is preserved. Another surface hoar/facet weakness was buried mid-December and can now be found down 70 cm in shallow snowpack areas, or as much as 1.5 m in deeper snowpack areas. It woke up during the last storm and has remained reactive to human triggers. This weak layer is responsible for several large human-triggered avalanches, including some with multiple burials, and the layer may continue to remain reactive for the foreseeable future.
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Avalanche Canada
