Avalanche Forecast South Columbia

Date Issued: Valid Until:

Avalanche Canada kdevine, Avalanche Canada

Avalanche Forecast

Wed Mar. 13th ยท 5:03PM

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Moderate

Problems

Storm Slabs Storm Slabs

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low
Storm slabs may be reactive to human triggering, especially in wind loaded areas, and on steep, sun exposed slopes if the sun comes out.

Confidence

Moderate -

Weather Forecast

WEDNESDAY NIGHT - Cloudy with clear periods / northwest wind, 10-20 km/h / alpine low temperature near -10THURSDAY - Mainly cloudy with isolated flurries / southwest wind, 20-40 km/h / alpine high temperature near -8 / freezing level 1400 mFRIDAY - Cloudy with sunny periods / southwest winds 10-25 km/h / alpine high temperature near -6 / freezing level 1600 mSATURDAY - A mix of sun and cloud / southwest winds, 15-30 km/h / alpine high temperature near -3 / freezing level 1800 m

Avalanche Summary

On Tuesday, there were reports of numerous natural and explosives triggered avalanches up to size 2, as well as human triggered storm slab avalanches up to size 1.5. Some of these were remoted triggered (triggered from a distance).There was also a report of a size 2 human triggered persistent slab avalanche on a southeast aspect at treeline. It is suspected that this avalanche failed on the early February persistent weak layer.On Monday, there were reports of numerous human triggered storm slab avalanches up to size 1.5 and several natural storm slab avalanches up to size 2.5.Reports on Saturday and Sunday include several natural and human triggered storm slab, loose dry and wind slab avalanches to size 1.5. Also on Sunday, was a skier triggered size 2 persistent slab avalanche on a west aspect at 2300m in the northern part of the region as well as a remotely triggered (from a distance) size 3 avalanche on a southwest aspect in the alpine. The second avalanche was in the south part of the region. Both of these were suspected to have run on a layer of facets.

Snowpack Summary

30-60 cm of recent storm snow is sitting mainly on facets (sugary snow), as well as surface hoar (feathery crystals) in sheltered areas and a crust on sun exposed slopes. There are two weak layers of surface hoar in the upper snowpack that were buried in late January and early February. They can be found between 60-120 cm below the surface. These layers consist primarily of surface hoar, though they may be associated with crusts on steeper, south facing slopes. These weak layers are most prominent on south facing slopes and all aspects below treeline. Avalanche activity on these layers has declined in recent days, however it may still be possible to trigger an avalanche in isolated areas such as steep cutblocks, large open glades, and steep south facing terrain.The lower snowpack is generally considered to be strong, except for shallow, rocky areas where the cold temperatures continue to facet (weaken) the snowpack.

Problems

Storm Slabs

Storm Slabs

25-50 cm of recent storm snow came in with moderate to strong southwest winds. Storm slabs may continue to be reactive, especially in wind loaded areas.

Use caution around wind loaded pockets near ridge crests and roll-overs.Be cautious of sluffing in steep terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2