Avalanche Forecast

Issued: Mar 13th, 2016 8:47AM

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

Avalanche Canada esharp, Avalanche Canada

Ongoing snowfall and southerly winds will add more load to already thick storm slabs and large cornices. Conservative terrain selection remains wise.

Summary

Confidence

Moderate

Weather Forecast

MONDAY: moderate to light snow starting overnight with 5-20cm expected by the end of the day,  mainly light westerly winds, 1200m freezing level. TUESDAY: light snowfall continues, moderate westerly winds, 1200m freezing level. WEDNESDAY: clearing, light and variable winds, 1200m freezing level.

Avalanche Summary

On Friday, two natural cornice triggered storm slabs were reported in the north of the region. One was a size 3 storm slab on a northeast aspect at 2000m and was 100cm thick. It was reported to have run full path to the end of the runout. The other was a size 2 on a northeast aspect at 2200m that was 30-60cm thick. On Thursday, a natural avalanche cycle occurred in the north of the region with storm slabs up to size 2.5 reported. Storm slabs are expected to remain touchy to human-triggering on Saturday and natural activity is possible in freshly wind loaded terrain.

Snowpack Summary

40-70cm of new snowfall has accumulated in sheltered areas with greatest amounts to the north of the region. Weaknesses within or at the base of the new storm snow may need a couple days to settle and strengthen. Southerly winds have created deep and dense slabs in lee terrain, probably well below ridge crests, while scouring windward slopes. This intense loading may have overloaded a weak layer of surface hoar buried at the beginning of February. This layer was primarily a concern in the South Chilcotin Mountains. Where it still exists, it would be 100-150 cm deep now. Ongoing stormy weather has also encouraged extensive cornice growth.

Problems

Storm Slabs

An icon showing Storm Slabs
Widespread storm slabs are expected to remain reactive to human-triggering, especially in wind loaded terrain.
Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain. >The new snow will requires several days to settle and stabilize. >Avoid freshly wind loaded features. >

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 5

Cornices

An icon showing Cornices
Cornices are large and fragile, avoid overhead hazard and venturing to close to ridge crests.
Give cornices a wide berth when travelling on or below ridges.>Extra caution needed around cornices with current conditions.>

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 5

Valid until: Mar 14th, 2016 2:00PM