Avalanche Forecast
Issued: Jan 4th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
shorton,
Avalanche Canada
Triggering slab avalanches is possible on steep and convex slopes in treeline and alpine terrain.
Summary
Confidence
Moderate
Avalanche Summary
No significant avalanche activity was reported on Tuesday.
Triggering large persistent slab avalanches remains a concern. The most recent report of a persistent slab avalanche was on Monday, when two size 2 persistent slabs were triggered on treeline features in northern parts of the region. These avalanches failed on 30 to 50 cm deep facet layers. Similar avalanches were reported in treeline terrain in southern parts of the region last Thursday and Friday.
Snowpack Summary
Recent storm snow continues to settle, with moist snow and crusts possibly forming on some surfaces. Recent strong wind has left wind slabs on lee terrain features, and some cross-loaded features due to outflow winds in coastal inlets. Several persistent weak layers may be found in the top metre of the snowpack, including a surface hoar layer buried on Dec 28 (20 to 40 cm deep) and a facet layer buried on Dec 23 (40 to 80 cm deep). These layers are increasing in strength, but could still be possible to trigger in specific areas. In alpine terrain, triggering one of these layers is most likely on steep rocky slopes where they present as facets, while in treeline terrain, it is most likely triggered on convex rolls in open trees where they present as preserved surface hoar.
Weather Summary
Wednesday night
Partly cloudy, no precipitation, 30 to 50 km/h wind from the southeast, treeline temperatures drop to -8 °C.
Thursday
Mix of sun and cloud, no precipitation, 20 to 40 km/h wind from the southeast, treeline temperatures warm to -4 °C.
FridayCloudy with flurries increasing in intensity throughout the day, 5 to 15 cm of snow by the late afternoon, 50 to 70 km/h wind from the south, freezing level climbs to 1500 m around Prince Rupert and Kitimat, but stays below 500 m around Shames and Terrace.
SaturdayMix of sun and cloud, no precipitation, 30 to 50 km/h wind from the southeast, freezing level drops to 500 m with treeline temperatures around -2 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Use caution when approaching steep and rocky terrian.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
- Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
Problems
Persistent Slabs
Several persistent weak layers in the top 20 to 80 cm of the snowpack have potential to produce size 2 avalanches if triggered. Facet layers are the primary concern in alpine terrain, while preserved surface hoar layers are the concern in treeline terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Wind slabs are likely gaining strength, but may still be possible to trigger on steep lee features along ridges.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 5th, 2023 4:00PM
