Avalanche Forecast

Issued: Apr 2nd, 2017 4:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Deep Persistent Slabs and Wind Slabs.

snow safety, Parks Canada

Banff Yoho Kootenay.

Sun effect will dramatically change the avalanche conditions at lower elevations tomorrow.

Summary

Weather Forecast

Convective flurries tomorrow with periods of light rain at lower elevations and snow up high, Overnight temperatures will drop to below -10 as the low and climb to plus 5 as a high tomorrow. Any sun affect will dramatically increase temperatures quickly.

Snowpack Summary

10-20cm of new, plus 20 cm from the past week sits over a firm 100 cm+ slab resting over weak basal facets at all elevations. Tests show easy to moderate sudden collapse results in these facets. A melts free crust is widespread below treeline and specific to steep solar aspects at treeline and above. Windslabs are specific to immediate alpine lees.

Avalanche Summary

No new avalanche activity observed today.

Confidence

Problems

Deep Persistent Slabs

The snowpack throughout the region has a weak base and remains suspect. Approach all avalanche terrain with suspicion and exercise conservative route choices. This problem will persist for the foreseeable future.

Be wary of slopes that did not previously avalanche.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 4

Wind Slabs

New cornice growth and small fresh windslabs have formed with the recent storm specific to immediate lees in the alpine..

Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: North, North East, East, South East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 3rd, 2017 4:00PM