Avalanche Forecast
Issued: Apr 3rd, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Loose Wet and Cornices.
JSmith,
Avalanche Canada
Lingering wind slabs may remain reactive to human triggers and wet loose avalanches are likely if the sun comes out. Avoid large south facing slopes and slopes with cornices overhead during the heat of the day.
Summary
Confidence
Weather Forecast
SATURDAY NIGHT: Partly cloudy / Light, north ridgetop wind / alpine low temperature -6 / Freezing level valley bottom.
SUNDAY: Mix of sun and cloud / Light, northwest ridgetop wind / alpine high temperature 0 / Freezing level 900 m.
MONDAY: Mostly cloudy / Strong, northwest ridgetop wind / alpine high temperature 1 / Freezing level 1000 m.
TUESDAY: Snow flurries/rain; 5-10 cm. / Moderate, southwest ridgetop wind / alpine high temperature 0 / Freezing level 1000 m.
Avalanche Summary
On Friday, explosive triggered wet loose avalanches up to size 2 and a naturally triggered size 2 storm slab were reported.
On Wednesday, naturally triggered glide slab avalanches were reported up to size 3. Glide cracks releasing as full depth glide slab avalanches are extremely difficult to predict. Best practice is to avoid slopes with glide cracks.
Snowpack Summary
40+ cm. of snow has accumulated at upper elevations over the past few days and will be most reactive in wind affected areas at treeline and above. Sunshine may trigger wet loose avalanches on solar aspects. Cornices are large, looming, and capable of triggering large avalanches when they fail.
At lower elevations, the snow was mixed with rain, soaking the snow surface, which then formed a hard crust.
At higher elevations, the new snow has added significant load to a couple of deeply buried weak layers. The first persistent weak layer was buried in mid-March and is around 100-180 cm. deep. It consists of surface hoar on sheltered northerly aspects around treeline and down between 150 to 250 cm. is another layer of surface hoar and facets, buried in mid-February. At this time, these layers linger in the snowpack but haven't recently been a reactive avalanche problem.
The lower snowpack is well settled and strong in most areas.
Terrain and Travel
- A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
- Back off slopes as the surface becomes moist or wet with rising temperatures.
- Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
- Avoid exposure to slopes that have cornices overhead.
Problems
Wind Slabs
Lingering wind slabs may remain reactive to human triggers. Use caution when transitioning into wind affected terrain.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Wet
Sunshine may trigger wet loose avalanches on steep solar aspects.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Cornices are large and looming along many ridgelines, and have likely grown with the recent snow and wind. They are capable of triggering very large avalanches when they fail.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 4th, 2021 4:00PM
