Avalanche Forecast

Issued: Jan 13th, 2017 7:52AM

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

Parks Canada Ian Gale, Parks Canada

Variable wind slabs lurk in alpine and tree-line lee features.  Pay attention to changes in terrain and loading patterns.

Summary

Weather Forecast

The Arctic ridge of high pressure will remain in place today keeping the weather cold and dry. Today expect a mix of sun and cloud, light Southwest winds and an Alpine high of -16*C. The Arctic ridge is expected to slowly start to shift over the weekend allowing slightly warmer temps through the weekend and significant snow next week.

Snowpack Summary

SW winds have created windslabs along exposed alpine ridges and cross-loaded features. These sit on a variety of old surfaces, from hard windslab to faceted soft snow in protected areas. The very cold temps and generally low snow have created a weak facetted snowpack. Field tests are producing mod-hard resistant planar results in the upper 60cm.

Avalanche Summary

Numerous loose and slab avalanches were observed earlier in the week from Mt Macdonald and Mt Tupper on steep extreme terrain. A few natural size 1-1.5 slab avalanches, likely from Monday, were observed from steep N-facing terrain on Avalanche Crest aswell.

Confidence

Wind effect is extremely variable

Problems

Wind Slabs

An icon showing Wind Slabs
Stubborn windslabs exist on alpine features(ridge-crests, cross-loading gullies) from mod SW winds. These slabs are variable in distribution so assess each slope independently. They will be most reactive on convex rolls and in unsupported terrain.
Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Watch for whumpfing, hollow sounds, and shooting cracks.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Jan 14th, 2017 8:00AM