Avalanche Forecast
Issued: Nov 29th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Loose Dry and Deep Persistent Slabs.
Timothy Johnson,
On Tuesday afternoon the Icefields Parkway from Athabasca Falls to Saskatchewan Crossing will be closed. A significant winter storm is forecasted for Jasper. Please plan to be out of the closure by 15:00.
Summary
Weather Forecast
Tuesday:
Periods of snow.
Accumulation: 15 cm.
Alpine temperature: High -3 C.
Ridge wind southwest: 25 km/h gusting to 60 km/h.
Freezing level: 1700 metres.
Wednesday:
Snow, heavy at times.
Accumulation: 42 cm.
Alpine temperature: Low -3 C, High -1 C.
Ridge wind southwest: 20 km/h gusting to 65 km/h.
Freezing level: 2000 metres.
Snowpack Summary
Around 25cm of new snow in the last 36 hours. Moderate SW winds are creating new thin wind slabs in alpine lees over old hard wind slab or previous wind scoured rock. The mid-pack is around 80cm thick above a thin crust near the ground in some locations. Rain and warm temperatures are eating away the snowpack at the lower elevations.
Avalanche Summary
Explosive control on Parker Slabs on Monday produced thin wind slabs not propagating far. A few small natural slab avalanches out of steep lee features were also observed. Also a notable large avalanche off Whistler Mountain running to mid path near Jasper.
Confidence
Problems
Wind Slabs
- Avoid steep lee and cross-loaded slopes
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Dry
- Be careful of loose dry sluffing in steep, confined or exposed terrain.
- Be careful with wind loaded pockets while approaching and climbing ice routes.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
The average 1 meter snowpack has a crust near the ground surrounded by weakening large grain facets. This is a layer to watch as our neighbors are experiencing activity on it.
- Avoid thin rocky or unsupported terrain features.
- Use caution on open slopes and convex rolls
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Nov 30th, 2021 4:00PM
