Avalanche Forecast

Issued: Mar 29th, 2021 4:00PM

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

snow safety,

Banff Yoho Kootenay.

Wind and available snow for transport will continue to build wind slabs. Also, there is some uncertainty as to whether storm slabs exist in isolated areas.

Summary

Weather Forecast

Sub zero temperatures will persist at valley bottom until Wednesday, it could drop to -20 at the ridge during the same period. Only a few cm's of snow is expected over the next few days. The wind will be strong from the West on Tuesday increasing to extreme late on Wednesday.

Snowpack Summary

15-35cm of settled storm snow at treeline with the higher amounts up 93N. New wind slabs in alpine and exposed treeline areas with strong to extreme S-SW winds. 20-50+ cm now sits over the March 19 interface of crust on solar aspects and facets on north aspects. Nov basal facets still prominent in shallow areas east of the divide.

Avalanche Summary

Sunshine patrol reported observing a natural size 2.5 windslab in Eagle Basin close to the ski area today. A Gaz-Ex controlled wind slab size 2 was triggered last night in the Bourgeau 5 slide path. Otherwise dry loose avalanches were observed that ran in gully features during the storm.

Confidence

Wind speed and direction is uncertain on Tuesday

Problems

Wind Slabs

Widespread wind slab development in alpine and some exposed treeline areas from strong to extreme SW winds and 15 to 35cm of new snow. Use caution in any steep or loaded terrain until you have a sense for how reactive the new snow is.

Use caution in lee areas. Recent wind loading have created wind slabs.
Be careful with wind loaded pockets, especially in steep confined alpine terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Loose Dry

There is still potential for the recent storm snow to sluff in steep terrain, especially in areas that received the largest amounts over the past 24 hours.

Be careful of loose dry power sluffing in steep, confined or exposed terrain.
On steep slopes, pull over periodically or cut into a new line to manage sluffing.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Mar 30th, 2021 4:00PM