Avalanche Forecast

Issued: Apr 6th, 2014 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.

aaron beardmore, Parks Canada

Banff Yoho Kootenay.

Rising freezing levels should be expected over the next day or two. Keep in mind that rapidly warming conditions are detrimental to the snowpack and increase avalanche risk.

Summary

Weather Forecast

Rising freezing levels over the next two days (possibly to 2300m) will hold the danger rating at considerable. On Tuesday night the forecast could see up to 25cm of snow with warm temperatures and strong wind. This will elevate the danger rating to high on Wednesday.

Snowpack Summary

New wind slabs 15-25 cm thick in the immediate lees. Western areas such as Emerald and Field have a deep and stable snowpack. Contrast this with the Lake Louise, Hwy 93 N, & Sunshine areas, where there is a weaker snowpack with sudden collapse very easy compression results on the basal depth hoar. A crust exists on all but N aspects.

Avalanche Summary

No avalanches were observed or reported today.

Confidence

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

Problems

Deep Persistent Slabs

Thin areas mainly E of the divide are still susceptible to triggering basal layers causing larger avalanches. Big triggers such as cornice failures could be enough load to trigger an avalanche on the ground level.

Avoid shallow snowpack areas where triggering is more likely.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Wind Slabs

Isolated wind slabs in the lees of alpine ridge crests will still be susceptible to human triggering in the short term.

Use caution in lee areas. Recent wind loading have created wind slabs.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 7th, 2014 4:00PM