Avalanche Forecast
Issued: Feb 27th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
rgoddard,
Avalanche Canada
Expect to find wind slabs created this past weekend in exposed areas.
Seek out sheltered and low-consequence terrain but be careful of dry loose avalanches for the best and safest riding.
Triggering a deep persistent slab remains possible, especially in areas with a thin snowpack.
Summary
Confidence
Moderate
Avalanche Summary
Since the weekend there have been numerous reports of storm slab, wind slab, and as well dry loose avalanches.
On Thursday a size 3 deep persistent slab avalanche occurred naturally near Kispiox. It was on a steep, alpine feature, failing near rocks at ridgecrest. On Wednesday at Hudson Bay Mountain, a size 2.5 deep persistent slab avalanche was triggered by a cornice fall. Several size 2-3 explosive-controlled deep persistent slab avalanches also occurred near Ningunsaw.
If you go into the backcountry this weekend, please consider submitting a MIN report.
Snowpack Summary
Although it is calm now, the previous southwest winds have redistributed recent low-density snow. Wind slabs and recent snow may be covering a firm, wind-affected surface in all exposed areas. In sheltered areas, surface faceting due to cold temperatures and/or soft surface snow may remain.
Several crusts, layers of facets, or surface hoar can be found in the top 150 cm of the snowpack. This mid-pack is generally showing good strength.
Weak layers of note are facets near the bottom of the snowpack, 150 to 200 cm below the surface.
The total height of snow at treeline is between 200 and 280 cm.
Weather Summary
Monday Night
Mostly cloudy, trace accumulation, winds southeast 10 km/h, treeline temperatures -12 ºC.
Tuesday
Mostly sunny, trace accumulation, winds northerly 15 km/h, treeline temperatures -10 ºC.
Wednesday
Cloudy, 8 cm accumulation, winds southwest 30 km/h gusting to 50, treeline temperatures hovering around -10 ºC.
Thursday
Mostly sunny, trace to 5 cm accumulation, winds 30 km/h gusting to 70, treeline temperatures -10 to -5 ºC.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Be mindful that deep instabilities are still present and have produced recent large avalanches.
- Avoid areas with a thin or variable snowpack.
- If triggered, loose dry avalanches may step down to deeper layers resulting in large avalanches.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
Problems
Wind Slabs
Stubborn wind slabs are to be expected from our previous storm system and may be found on nearly all aspects at higher elevations.
Where the new snow is not wind-affected, make sure to watch out for dry loose avalanches in extreme terrain.
Although it is forecasted to remain cool, the sun can pack a punch this time of year. Consider slab formation and reactivity to increase with increased solar input.
Aspects: North, North East, East, South East, South, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
We continue to receive reports of large deep persistent slab avalanches, failing on facets (weak sugary crystals) near the base of the snowpack. Although triggering an avalanche on these deeply buried layers is unlikely, the result would be a large destructive avalanche.
Avoid shallow areas, and steep, rocky start zones.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 28th, 2023 4:00PM
