Avalanche Forecast
Issued: Mar 2nd, 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.
ahanna,
Avalanche Canada
The best snow and safest avalanche conditions can be found in sheltered terrain at lower elevations. If you venture up towards the alpine, watch out for stiff but reactive wind slabs and steer clear of cornices. Also be mindful that deep instabilities still exist and are most likely to be triggered from thin, rocky spots.
Summary
Confidence
Avalanche Summary
On Thursday our field team observed numerous wind slab avalanches up to size 1.5, with crowns up to 50 cm deep at Sinclair.
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 characterizes the snow surface at upper elevations. Exposed windward aspects have been scoured. Wind slabs may be found sitting unusually low down in start zones and lees. In sheltered areas, 40-50 cm of recent snow may be sitting over a layer of small facets.
Several other crusts, layers of facets, or surface hoar can be found in the top 150 cm of the snowpack, but are not of great concern at present.
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
Thursday night
Up to 5 cm new snow. Moderate westerly wind. Alpine low -13 ºC.
Friday
A mix of sun and cloud. Wind easing to light southerly. Alpine high -11 ºC.
Saturday
A mix of sun and cloud. Moderate easterly wind. Alpine high -10 ºC.
Sunday
Mostly sunny. Light to moderate easterly wind. Alpine high -15 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 in start zones due to recent strong winds.
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. But they can also be triggered by the weight of a person from shallow snowpack areas, and 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 3rd, 2023 4:00PM
