Avalanche Forecast

Issued: Mar 25th, 2018 4:00PM

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

aaron beardmore, Parks Canada

Banff Yoho Kootenay.

Conditions will change very little Monday. Tuesday expect precipitation and wind. Danger ratings Tuesday and beyond will depend on actual snowfall amounts and wind transport. Stay tuned.

Summary

Weather Forecast

Cooler temps will remain on Monday. Expect to see cloud cover and very light accumulations of snow (trace). Up to 20cm is expected to arrive on Tuesday. Wind will also be increasing into the moderate range from the SW.

Snowpack Summary

Cooler temps this weekend will keep lower elevation melt free crusts intact. On solar aspects this crust is present to ridgetop. Small wind slabs found in the high alpine. Concern still exists for last weeks storm snow where it sits on a buried suncrust (down 20-30 cm) on south and west aspects. Shallow snowpack areas are also still a concern.

Avalanche Summary

An ice triggered avalanche on the highway path on Mt. Stephen buried the highway Saturday night. This large piece of ice did not trigger a slab, the ice mass and snow that it entrained created the volume of debris.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Tuesday

Problems

Wind Slabs

Wind slabs and wind effect can be found in the alpine. Wind slabs are unlikely to release naturally but can be triggered by skiers and climbers, especially near ridge crest.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

Concern still exists for last weeks storm snow (20-30 cm) where it overlies a crust on solar aspects. Some recent avalanches have been observed on this interface.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Mar 26th, 2018 4:00PM