Avalanche Forecast

Issued: Mar 4th, 2013 4:26PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Storm Slabs.

brian webster, Parks Canada

Banff Yoho Kootenay.

Storm snow on south aspects may become unstable due to strong solar radiation. Be aware of afternoon heating on sunny aspects.

Summary

Weather Forecast

A ridge of high pressure will develop over the area on Monday. Light southerly winds and seasonal temperatures with high diurnal swings are forecast. The ridge breaks down on Tuesday and a weak front passes through with slightly warmer temperatures and light precipitation.

Snowpack Summary

Up to 60 cm of storm snow since Friday is settling and bonding to previous surfaces. Cool temperatures have tightened the upper pack and has promoted bonding within the storm snow and on the storm snow interface, however we still expect to see some touchy storm slabs, and lingering wind slabs in the alpine.

Avalanche Summary

Explosive control on highway paths in Yoho Park produced only minimal results with little slab propagation. Control work on Sunshine Road produced a Class 3.5 that ran to ground on a slope that previously had not slid this winter. Natural over Cascade waterfall in afternoon withÂ solar heating.

Confidence

Problems

Storm Slabs

60 cm of recent storm snow has created unstable storm snow conditions. The natural cycle is over and cooler temperatures have tightened up the upper pack, however we still expect to see touchy storm slab conditions over the next few days.

Minimize exposure to sun exposed slopes when the solar radiation is strong.Use caution in lee areas in the alpine. Recent wind loading have created wind slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 3

Valid until: Mar 5th, 2013 4:00PM