Avalanche Forecast

Issued: Apr 20th, 2024 4:00PM

The alpine rating is low, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs.

mconlan, Avalanche Canada

Purcells, South Rockies, Dogtooth, East Purcell, Bull, Crowsnest North, Crowsnest South, Elkford East, Elkford West.

Isolated pockets of wind slabs may linger in steep terrain in the alpine.

Summary

Confidence

Moderate

Avalanche Summary

Riders triggered small loose and wind slab avalanches on Friday in steep northerly alpine terrain. Looking forward, it may remain possible for humans to trigger similar avalanches as the recent snow slowly bonds to the snowpack.

Snowpack Summary

Northerly alpine slopes hold 10 to 20 cm of settled storm snow that overlies a hard melt-freeze crust. Isolated wind slabs may linger in steep northerly alpine terrain. All other aspects and everywhere below treeline have a hard surface crust. A dusting of snow at high elevations Saturday night will fall onto these surfaces.

The remainder of the upper snowpack is a mix of hard snow and crusts. The lower snowpack contains old weak layers that are currently dormant.

Weather Summary

Saturday Night

Cloudy with 2 to 5 cm of snow or rain at lower elevations. 20 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1700 m.

Sunday

Mostly cloudy. 20 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1600 m.

Monday

A mix of sun and cloud. 10 km/h northwest ridgetop wind. Treeline temperature 0 °C. Freezing level rising to 2000 m.

Tuesday

Mostly sunny. 10 km/h southwest ridgetop wind. Treeline temperature 4 °C. Freezing level rising to 2500 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Carefully evaluate steep lines for wind slabs.
Wind slabs may be poorly bonded to the underlying crust.
When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.

Problems

Wind Slabs

Wind slabs may linger on shaded aspects in steep, alpine terrain. Assess for slabs prior to entering high-consequence terrain.

Aspects: North, North East, East, North West.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 1.5

Valid until: Apr 21st, 2024 4:00PM