Avalanche Forecast
Issued: Mar 13th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
jsmith,
Avalanche Canada
New snow and moderate south wind may form reactive wind slabs at treeline and above.
Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Summary
Confidence
Moderate
Avalanche Summary
A few small (size 1) naturally triggered wind slabs on steep northwest aspects at treeline and above were reported on Sunday.
Snowpack Summary
10-15 cm new snow and moderate south wind has formed small wind slabs on lee aspects at treeline and above.
Below the new snow, is generally hard surfaces from extensive wind effect or a thin sun crust on steep, sunny slopes.
The middle of the snowpack is generally well settled and strong.
A weak layer of large and weak facets is found near the base of the snowpack. This layer is of greatest concern in shallow snowpack areas in the north and east of the region.
Weather Summary
Monday Night
Partly cloudy with isolated flurries; 0-3 cm / 30 km/h southwest ridgetop wind / Low temperature at treeline around -16 C
Tuesday
Mix of sun and cloud / 30 km/h southwest ridgetop wind / High temperature at treeline around -10 C
Wednesday
Mostly cloudy with isolated flurries; 0-5 cm / 30 km/h southwest ridgetop wind / High temperature at treeline around -9 C
Thursday
Sunny / 30 km/h southwest ridgetop wind / High temperature at treeline around -6 C
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.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
- Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
- Sheltered low elevation terrain will likely offer the best and safest riding today.
Problems
Wind Slabs
10-15 cm new snow and moderate south wind has formed small wind slabs on lee aspects at treeline and above.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
A weak layer of facets exists near the base of the snowpack. The likelihood of human triggering is low given the layer's depth, but large triggers such as cornice failures or smaller avalanches in motion have the potential to produce very large avalanches with surprisingly wide propagation. Suspect terrain for human triggering includes steep, shallow, and rocky terrain where the snowpack transitions from thin to thick.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 14th, 2023 4:00PM
