Avalanche Forecast

Issued: Mar 25th, 2014 9:06AM

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

Avalanche Canada triley, Avalanche Canada

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Wednesday

Weather Forecast

Overnight and Wednesday: Expect 5-10 mm of precipitation overnight that should be 10-15 cm of snow at alpine elevations. Strong South-Southwest winds are forecast that should drop to light in the morning when the snow fall ends. Freezing level should drop down to about 600 metres overnight and rise to about 1300 metres during the day. There is a chance of broken skies and sunny periods in the afternoon.Thursday: Overcast with light Easterly winds, some light flurries, and freezing levels rising to 1400 metres.Friday: Snow starting in the morning as Southwest winds build to moderate values. Freezing levels rising to 1600 metres.

Avalanche Summary

No new reports of avalanches.

Snowpack Summary

10-15 cm of new snow is reported to be settling and bonding to the recent storm snow. The persistent weak layers from early March and early February continue to be a concern. The March weak layer of wind-scoured crusts, melt-freeze crusts, and/or surface hoar is reported to be down 70-80 cm. The February crust/facet/surface hoar layer is now deeply buried down 150-250 cm and may still be triggered by heavy loads like cornice falls or storm slab avalanches in motion. Long fracture propagations resulting in very large avalanches are possible with this layer. Avalanches releasing on these layers may step down to the ground during periods of strong solar radiation or warm spring rain.

Problems

Storm Slabs

An icon showing Storm Slabs
Forecast new snow and strong winds are expected to develop new storm slabs. Watch for pockets of wind transported snow at higher elevations.
Extra caution needed around cornices with current conditions.>Use ridges or ribs to avoid pockets of wind loaded snow.>Minimize exposure during periods of heavy loading from new snow, wind.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 4

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Deeply buried persistent weak layers continue to be a concern. Heavy loads like cornice falls or storm slabs in motion may trigger the PWL resulting in very large avalanches.
Be aware of thin areas that may propogate to deeper instabilites.>Be aware of the potential for full depth avalanches due to deeply buried weak layers.>Give cornices a wide berth when travelling on or below ridges.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Mar 26th, 2014 2:00PM