Avalanche Forecast
Issued: Apr 19th, 2022 4:15PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Loose Dry.
Lisa Paulson,
Recent snow and strong wind Tuesday has bumped up the hazard creating fresh windslabs on underlying crusts. Snow amounts vary across the region and with elevation. Time to take a step back in terrain choices.
Summary
Weather Forecast
Up to 5 cm is forecasted for Tuesday night bringing storm totals to 10-20 cm coupled with strong SW wind. Wednesday, as the system departs, expect cloudy skies with sunny periods and isolated flurries. Temperatures will remain cool (-4C for an alpine high for Wednesday)
Snowpack Summary
5-10 cm of new snow fell on Tuesday with strong SW wind. This overlies the previous surface of 10-20 cm of facetted snow over a varying thickness crust that exists on all aspects except high elevation north (>2500m). There is widespread wind effect in the alpine. Multiple crusts exist within the mid-pack on all aspects/elevations except high north.
Avalanche Summary
Poor visibility today, but we suspect some natural avalanches to have occurred. Ski hill forecasters report ski cutting touchy wind slabs 10-40 cm thick on all aspects that ran far for their size on underlying crusts. Cornices continue to be of concern with several natural and skier triggered cornice failures occurring over the past week.
Confidence
Due to the number of field observations
Problems
Wind Slabs
10-20 cm new with strong SW wind on Tuesday created wind slabs generally 20-30 cm thick, but up to 40 cm in the Lake Louise region. The reactive slabs were found on the lees of features on all aspects running far for their size on underlying crusts.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Dry
The new snow may sluff easily off of hard steep surfaces and knock you off your feet.. We may see loose dry avalanches triggered with solar input as skies clear for Wednesday. This may be enough to trigger the fresh windslabs in alpine terrain.
- Be careful of loose dry power sluffing in steep terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 20th, 2022 4:00PM
