Avalanche Forecast
Issued: Apr 13th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
trettie,
Avalanche Canada
Watch for signs of instability as you move through terrain.
A deeply buried weak layer from early April remains rider triggerable.
Summary
Confidence
Avalanche Summary
Many slab avalanches were observed on Thursday, the majority of these avalanches occurred in the north of the region. The avalanches were triggered naturally and by riders in alpine terrain on all aspects. The avalanches were 40 to 80 cm deep and occurred within the recent storm snow as well as on the weak layer from early April. Remotely triggered avalanches involving this layer have also been reported.
Snowpack Summary
Recent snow and southwest wind formed wind slabs in lee terrain features at higher elevations. A crust exists on or near the surface on south and west facing slopes at treeline and above. Below treeline the snow surface is moist.
Around 50 to 100 cm of snow overlies a hard melt-freeze crust from early April. This snow is slow to bond to the crust where pockets of weak surface hoar or faceted grains rest on the crust, which is most likely on northerly aspects at treeline and alpine elevations.
There are no deeper concerns at this time.
Weather Summary
Saturday Night
Mostly cloudy with up to 5 cm of new snow. 15 to 35 km/h southwest alpine wind. Treeline temperature -4°C.
Sunday
A mix of sun and cloud with 2 to 4 cm of new snow in AM. 20 to 40 km/h southwest alpine wind. Freezing level rising to 1100 m.
Monday
A mix of sun and cloud with 1 to 3 cm of new snow. 10 to 20 km/h west alpine wind. Freezing level rising to 1000 m.
Tuesday
Sunny. 5 to 15 km/h northeast alpine wind. Freezing level rising to 1200 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Carefully evaluate steep lines for wind slabs.
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
- Remote triggering is a concern, watch out for adjacent and overhead slopes.
Problems
Persistent Slabs
A layer of facets over a crust has produced large rider and remotely triggered avalanches over the past few days.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Assess for wind slabs in steep lee terrain features. Small wind slabs could step down to a weak layer over a hard crust buried around 50 to 100 cm deep, forming large avalanches.
Aspects: North, North East, East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 14th, 2024 4:00PM
