Avalanche Forecast

Issued: Mar 27th, 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 Cornices.

grant statham, Parks Canada

Banff Yoho Kootenay.

Avalanche conditions are slowly improving. Today was the first day with no new avalanches observed, so the natural cycle is over, but human triggering remains likely. Continue to minimize your exposure to avalanche terrain unless it has already slid.

Summary

Weather Forecast

Snowfall expected over the next few days, with 5 cm on Tuesday, 10 cm on Wednesday and 3 cm on Thursday. Freezing levels should reach 1800m each day, with alpine temperatures ranging from -1 to -12. Winds are generally moderate but will pick up to strong through Tuesday night.

Snowpack Summary

10 cm of snow sits over a solid 100cm+ slab which rests precariously over the weak basal facets at treeline and above. Tests produce consistent sudden collapse results in the facets, and this will not become stronger soon. The surface snow is of a mix of soft snow in the shade, melt-freeze snow below treeline, and sun crust on sun exposed slopes.

Avalanche Summary

No new avalanches were reported or observed today. This is the first day in about two weeks that we have not seen, or heard of a fresh avalanche in our forecast region.

Confidence

Due to the number of field observations

Problems

Deep Persistent Slabs

Natural activity has decreased, but the snowpack has a weak base and remains quite suspect. Continue to approach avalanche terrain with suspicion and avoid most large slopes steep enough to slide. Human triggering remains likely in specific areas.

Be wary of slopes that did not previously avalanche.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Cornices

There has been an increasing frequency of cornice failures this past week. Be wary of this as we transition into spring (cornice season). They are a hazard underfoot on ridge crests, and from overhead if you travel below one. GIve them a wide berth.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Mar 28th, 2017 4:00PM