Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Sunshine, West Side 93N.
High elevation winds have been strong to extreme for the last week, so be on the lookout for windslabs if venturing into high, windy spots.
Deep slabs haven't been observed in days, but a weak snowpack persists in shallow areas - ski the thick, avoid the thin.
Confidence
Moderate
Avalanche Summary
No avalanches were observed or reported on Jan 14
Snowpack Summary
Over the past week, ~10cm has accumulated, accompanied by strong to extreme west winds that have formed slabs in exposed high alpine areas. The recent snow rests on a layer of facets and surface hoar, although we haven't seen many avalanches sliding on this layer yet. The middle and bottom of the snowpack are weak, with depth hoar and facets near the ground. An average of 60-100cm of snow can be found at treeline elevations.
Weather Summary
Strong westerly winds at ridgetop with warm temperatures in eastern areas will dominate on Wednesday. This will be accompanied by variable cloud cover and trace snow accumulations.
Thursday, we expect extreme SW winds accompanied by up to 5 cm new snow.
On Friday, we will see cooling temperatures and easing winds as arctic air moves in for the weekend.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Avalanche Problems
Wind Slabs
Recent snow and extreme NW to SW wind have developed small slabs in high alpine terrain that is exposed to the wind. These may run further than expected if they pick up facetted snow in steep gullied terrain.
Aspects: North, North East, East, South East, South.
Elevations: Alpine.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2
Deep Persistent Slabs
Weak facets exist at the base of the snowpack. Although we haven't seen much avalanche activity on this layer in a while, the snowpack structure is weak and large open slopes at treeline and in the alpine remain suspect.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely
Expected Size: 1.5 - 2.5