Avalanche Forecast
Issued: Feb 4th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Persistent Slabs and Cornices.
ahanna,
Avalanche Canada
In the wake of the storm, stick to simple terrain on Sunday. As fair weather settles in this week and inspires you to explore, be sure to start small and ease into terrain cautiously. Wind slabs are likely to remain triggerable by riders and uncertainty around a buried weak layer (and its potential to produce large avalanches) is on our minds.
Summary
Confidence
High
Avalanche Summary
We expect a widespread natural storm slab avalanche cycle to have occurred during the storm Friday and Saturday. Rider-triggered wind slab avalanches will remain likely for a few days after the storm.
Prior to this storm, recent avalanche observations have been limited to small wind slabs and cornice falls reported by our field team.
If you're heading out into the mountains, please consider sharing your observations on the Mountain Information Network!
Snowpack Summary
30-60 cm of new snow has been redistributed by strong northwesterly to westerly winds. Expect to find deep wind slabs on leeward aspects, and scouring on exposed windward aspects. After a milder storm over Sunday night, wind-ravaged surfaces may be blanketed by 5-15 cm of fresh snow.
The mid snowpack consists of 30-100 cm of recent January snow, poorly bonded to a crusty underlying lower snowpack.
Weather Summary
Saturday night
Intense localized snow squalls 3-5 cm per hour accompanied by strong northwesterly wind gusting 110 km per hour through the evening. Snowfall and wind easing mid night. Temperature -12 to -15 C.
Sunday
Scattered flurries through the day, intensifying in the evening as the next system approaches. Westerly wind 30 km/h switching southwest and increasing in the afternoon. Temperatures rising through the day, peaking around -5 C overnight.
Monday5-15 cm of new snow overnight, clearing to a mix of sun and cloud. Light westerly wind. Alpine temperatures near -5 C in the morning dropping to -12 C through the day.
TuesdaySunny, light easterly wind, alpine high temperature around -10 C.
A quiet stretch of weather until late in the week.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Start with simple terrain and gather information before thinking about more committing features.
- Avoid freshly wind loaded terrain features.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
Problems
Wind Slabs
Recent snow and strong wind have formed wind slabs in leeward terrain features. Identify wind slabs by looking for stiff or drifted snow. Typical places to find them include beneath ridge crests and roll-overs and beside protruding features on cross-loaded slopes. Wind slabs may remain triggerable by riders for several days after natural avalanche activity subsides.
Aspects: North, North East, East, South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
A poorly bonded layer of faceted particles sits over a slippery crust ~50-150 cm deep. It has shown reactivity in recent snowpack tests and if triggered, it has potential to produce large, destructive avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Cornices have grown with the recent snow and wind. Give cornices a wide berth when travelling on or below ridges. Cornice falls can be dangerous on their own and they can trigger slab avalanches on slopes below.
Aspects: North East, East, South East, South, South West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Feb 5th, 2023 4:00PM
