Avalanche Forecast

Issued: Apr 12th, 2014 9:58AM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Loose Wet, Wind Slabs and Deep Persistent Slabs.

mbender, Avalanche Canada

South Columbia.

Summary

Confidence

Fair - Freezing levels are uncertain on Sunday

Weather Forecast

Sunday: Mostly clear and sunny. Light west winds. Freezing level 1700m..Monday: Mix of sun and cloud. Light west winds. Freezing level 2300m.Tuesday: Cloudy with scattered flurries. Light westerly winds. Freezing level 1700m.

Avalanche Summary

Recent reports from Friday indicate natural avalanches running to size 3 from southerly aspects in the alpine and at tree-line.

Snowpack Summary

Warm temperatures resulted in the freezing level reaching to almost 2500m early this week. This has helped to settle out last weeks storm snow, it's reported to be bonding well to the old surface. Strong winds out of both the SW and NW have redistributed what little dry snow still exists at upper elevations into wind slabs immediately lee of ridge crest.Three persistent weak layers exist in the highly variable snowpack of the South Columbia region:The mid-March sun crust/surface hoar layer down 50-80cm seams to have gone dormant for the time being.The early-March crust/facet/surface hoar layer down around 80-120cm has become less susceptible to human triggering, but still has the capacity to produce large avalanches.The mid-February crust/facet/surface hoar combo is typically down 150 - 200cm. Direct triggering of this layer has become unlikely, however, cornice fall, a smaller avalanche in motion or prolonged warming could wake this layer up, which would result in very large and destructive avalanches.

Problems

Loose Wet

Expect to see an increase in avalanche activity on solar aspects with extended periods of solar radiation.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Wind slabs immediately lee of ridge crest may still be sensitive to human triggering.

Assess start zones carefully and use safe travel techniques.>Be careful with wind loaded pockets, especially near ridge crests and roll-overs.>Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Deep Persistent Slabs

The potential for very large deep slab avalanches needs to remain on your radar. Cornice fall, strong solar, warming temperatures or a surface avalanche in motion could wake up these deep persistent weak layers.

Be aware of the potential for very large, deep and destructive avalanches due to the presence of deeply buried persistent weak layers.>Carefully evaluate big terrain features by digging and testing on adjacent, safe slopes.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

4 - 8

Valid until: Apr 13th, 2014 2:00PM