Avalanche Forecast
Issued: Mar 30th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
rgoddard,
Avalanche Canada
Snow and wind arrive on Friday. Amounts will vary widely throughout our region.
Seek out sheltered areas free of wind slabs and be wary of how the new snow is bonding to old surfaces.
Summary
Confidence
Avalanche Summary
On Tuesday there was a skier-triggered wind slab avalanche in our area. It was size 0.5 and partially buried the person but there were no injuries.
Two size-one wind slab avalanches were reported on Monday. These were skier controlled and naturally caused. They were on north-facing aspects and were at a depth of 5 cm failing on the recent snow.
Snowpack Summary
New snow falling Friday will be redistributed by southwest winds.
Below the new snow is a melt-freeze crust that exists on all aspects at treeline and below, and on solar aspects to the mountain top. On high north aspects is a mixture of decomposing dry snow and small surface hoar in isolated locations.
The mid-snowpack is generally strong but the lower snowpack is a different story.
A weak layer of sugary facets is still prominent at the base of the snowpack. Small surface avalanches and cornice falls are the most likely things to trigger this layer. However, there remains a concern for human triggering in rocky, shallow, or thin-to-thick snowpack areas at treeline and above.
Weather Summary
Thursday Night
Cloudy, trace accumulation, winds southwest 15 to 20 km/h, freezing level dropping down to valley bottom.
Friday
Cloudy, 5 to 10 cm accumulation, winds southwest 20 to 30 km/h gusting to 50, freezing level up to 1300 m.
Saturday
Cloudy, 5 to 10 cm accumulation overnight and potentially another 5 to 10 during the day, winds southwest 15 to 25 km/h, freezing levels at the valley bottom.
Sunday
Cloudy, up to 10 cm accumulation, winds variable and light, freezing level at the valley bottom.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Make observations and assess conditions continually as you travel.
- Carefully evaluate steep lines for wind slabs.
- In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
Problems
Wind Slabs
Snow that will start falling Friday will be redistributed by southwest winds. Expect reactive wind slabs. Winds from earlier this week were predominantly from the northeast, therefore you may find wind slabs on all aspects.
There is a potential for more than expected snow to fall in our region. In areas where you see more than 15 cm accumulate, be suspect of storm slabs as their reactivity could be increased by the lack of cohesion of the surfaces that they will bury.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 31st, 2023 4:00PM
