Avalanche Forecast
Issued: Mar 20th, 2022 4:16PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
Grant Statham,
We have a lot of uncertainty about the sensitivity and distribution of the current windslab problem. Observations from the high alpine are limited, but given our observations of drifting snow at ridge crests, we're concerned about windslab formation.
Summary
Weather Forecast
A weak ridge over the area gives clearing skies overnight Sunday, but on Monday we switch to a SW flow (storm track) and clouds move into the area. No precipitation is expected and light winds; a similar day as was Sunday. Tuesday expect a RAPID warm-up and strong SW winds with FL's exceeding 2000m for Wednesday and snow/rain on the way.
Snowpack Summary
20-50 cm of storm snow forming fresh wind slabs in alpine and some treeline terrain with mod-strong SW winds. On solar aspects a variety of buried sun-crusts down 30-60 cm are producing moderate results in tests. In addition there is a buried temperature crust at lower elevations that exists on all aspects, and has been reactive in Kootenay Park.
Avalanche Summary
No new activity reported Sunday. Explosive control in Kootenay Park on Thursday produced unexpectedly large avalanches at low elevations. On Sunday, Bourgeau-Left waterfall (next to Sunshine gondola) released a large natural avalanche that ran over the waterfall and hit Healy Creek. This may have been triggered by a cornice or strong solar effect.
Confidence
Problems
Wind Slabs
Sunday was windy and we observed much wind effect across the snowpack on open slopes at treeline and especially in the high alpine. These slabs will be quite sensitive initially before they begin to bond.
- Watch for surface cracking and stiffer surface layers of snow. Avoid wind loaded terrain.
- Pay attention to overhead hazards like cornices which could trigger slabs or larger sluffs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Buried crust/facet layers exist in the upper snowpack on solar aspects and all aspects below 1700m. Recent tests show moderate sudden planar results. Exercise caution in areas where these crusts exist, there is uncertainty about how they will react.
- Be aware of the potential for wide propagations.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 21st, 2022 4:00PM
