Avalanche Forecast

Issued: Mar 9th, 2016 4:00PM

The alpine rating is high, 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.

Expect a small avalanche cycle Thursday if a significant storm arrives. The weak midpack is still causing problems in isolated areas.

Summary

Weather Forecast

Forecast snowfall amounts for the next day and a half range from 10-40 cms depending on the model chosen. Deeper amounts are the basis for the danger rating.

Snowpack Summary

10-20 cm of new snow over the last couple days, becoming moist below 1700m. Buried sun crusts on solar aspects. Recent West winds have formed soft slabs in lee areas of the alpine. A firm upper snow pack sits over a generally weak mid-pack of facets and depth hoar. In shallow areas snowpack tests results are typically collapses near the ground.

Avalanche Summary

No new avalanches were reported today. A couple of recent close calls are worth noting however: Monday a skier accidental size 2.5 on the Collie Glacier and on Sunday a skier accidental size 2.5 near Bow Summit.

Confidence

Track of incoming weather systems is uncertain

Problems

Deep Persistent Slabs

The mid-pack facets remain weak, especially in thin or rocky areas. Avoid steep or unsupported terrain, and watch for signs of instability such as whumphing and cracking. This weakness will be present for some time.

Be aware of thin areas that may propogate to deeper instabilites.Caution around convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Wind Slabs

Recent W winds and new snow have created soft slabs in leeward ares near ridge crests. Pay attention to the snow surface conditions while touring - you can usually detect wind slabs easily and avoid these spots.

If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Mar 10th, 2016 4:00PM