Avalanche Forecast
Issued: Feb 21st, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
jcoulter,
Avalanche Canada
Reverse loading from moderate to strong northeast winds continues to build potential wind slabs on unusual aspects. With cold temps and significant wind chill, even a small avalanche or accident could have big consequences.
Summary
Confidence
Weather Forecast
MONDAY NIGHT: Partly cloudy, trace of new snow, moderate to strong easterly winds, low of -25.
TUESDAY: Sunny with cloudy periods. Moderate to strong northeast winds and an alpine high of -20 will combine for some uncomfortable wind chill.
WEDNESDAY: Mostly sunny and winds dropping to light from the northeast. Alpine high of -16.
THURSDAY: Partly cloudy, light westerly wind, alpine high of -10.
Avalanche Summary
On Monday skier controlled small (size 1.0) wind slabs were reported in fan features. On Sunday small (size 1.0-1.5) natural, skier and explosives triggered dry loose and slab activity was reported. On Saturday there was a machine triggered avalanche, likely on an old buried surface hoar layer in an open gully feature in the Rolling Hills area.
Snowpack Summary
The most recent 5-15 cm of snow has been getting redistributed by moderate to strong northeast winds and building wind slabs in unusual places. Cornices are being stripped back. In south-facing terrain, new snow sits on top of melt-freeze crusts, and in open terrain recent snow sits over old firm wind-affected surfaces.
A buried surface hoar layer may be found 30-50 cm deep on sheltered, north-facing treeline-type features. This layer has become significantly less reactive and harder to find, but it can still catch riders off guard in isolated areas. Check out this recent MIN from the Rolling Hills area for an example.
The lower snowpack is well consolidated, with a crust/facet layer found near the bottom of the snowpack. It is currently considered dormant, but could become active later this season. Check out the forecaster blog for more information.
Terrain and Travel
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Problems
Wind Slabs
Watch for pockets of wind slab on various aspects in exposed terrain and around ridgelines. The storm initially came in with southwest winds, but with the intrusion of arctic air, winds switched to the northeast potentially building slabs in less common locations.
These slabs have formed on top of old crusts and hard wind-pressed snow and there is uncertainty about how quickly they will bond to old surfaces.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 22nd, 2022 4:00PM
