Avalanche Forecast
Issued: Mar 4th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Deep Persistent Slabs and Cornices.
dnylen,
Avalanche Canada
Seek out sheltered terrain and be suspicious of wind affected snow, like hard windslabs, cornices and cross-loaded slopes. Thin rocky areas will remain a concern in this complex snowpack.
Summary
Confidence
Avalanche Summary
Our field team continues to observe numerous natural wind slab and cornice triggered avalanches up to size 2.
Last week, several large deep persistent slab avalanches were reported in the alpine, including a natural size 3 near Kispiox, a cornice-triggered size 2.5 at Hudson Bay and several explosive controlled size 2-3 near Ningunsaw.
Snowpack Summary
Extensive wind effect from all directions characterizes the snow surface at upper elevations. Exposed windward aspects have been scoured, pillows of deep snow and wind slabs may be found sitting unusually low down in start zones and lees. Cornices are large and can be found on a number of aspects from persistent variable winds.
In sheltered areas, 40-50 cm of recent snow may be sitting over a layer of small facets and cold snow that feels upside down
Several other crusts, layers of facets, or surface hoar can be found in the top 150 cm of the snowpack, but have not shown any avalanche activity or tests results yet.
The lower snowpack consists of weak, basal facets which may become active with any rapid change or shock to the snowpack, such as heavy loading or dramatic warming. Snowpack depths range from 60 to 280 cm at treeline.
Weather Summary
Saturday night
Possible flurries. Moderate easterly wind. Alpine low -15 ºC.
Sunday
Mostly sunny. Moderate easterly wind. Inversion up to -10 ºC in the alpine .
Monday
Mix of sun and cloud. Moderate southeasterly wind. Inversion in the morning. Alpine high -10 ºC.
Tuesday
Mix of sun and cloud. Possible flurries. Variable moderate wind. Alpine high -17 ºC.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Seek out wind sheltered terrain below treeline where you can avoid wind slabs and find great riding.
- Be especially cautious as you transition into wind affected terrain.
- Stay off recently wind loaded slopes until they have had a chance to stabilize.
- Be mindful that deep instabilities are still present and have produced recent large avalanches.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Problems
Wind Slabs
Recent winds have hammered the surface at wind-exposed elevations. Wind slabs may be found unusually low on slopes due to recent strong winds and on all aspects due to changes in wind direction.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Weak, sugary crystals at the bottom of the snowpack have produced large avalanches recently. These avalanches are most likely to be triggered by large loads such as cornice falls. However, in shallow snowpack areas they can also be triggered by the weight of a person and could propagate out to deeper snow resulting in large, destructive avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Cornices have seen significant growth recently. Give them a wide berth whether travelling on or below ridgelines. Cornices can be dangerous on their own and they can also act as large triggers to deep slab avalanches on slopes below.
Aspects: North, North East, East, South East, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Mar 5th, 2023 4:00PM
