Avalanche Forecast

Issued: Apr 2nd, 2013 8:12AM

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

ali haeri, Parks Canada

Glacier.

Positive overnight temperatures to 2200m will have prevented a crust from forming keeping the snow more unstable today with added sunshine.

Summary

Weather Forecast

The ridge of high pressure is slowly weakening, cloud cover is expected to increase this evening bringing very light precipitation into Wednesday morning. Brief clearing on Thursday before a more significant system arrives Thursday night.

Snowpack Summary

Multiple crusts and moist snow in the upper one meter of the snow pack on south, east and west aspects. On due north aspects there may still be dry snow to be found at tree line and above.

Avalanche Summary

4 loose natural avalanches from size 1.5 to 2.5 along the highway corridor.Numerous loose wet avalanches to size 2.5 on the west face of Mt Mcgill.

Confidence

on Tuesday

Problems

Loose Wet

With no refreeze overnight at 2100m, it will not take long for direct solar radiation to trigger avalanches on sunny aspects.

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

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Deep Persistent Slabs

Glide cracks, gaping cracks in the snowpack, exist on many slopes and have been failing with the warm temps. They can fail unpredictably, and release the entire snowpack to the ground.

Be aware of thin areas that may propogate to deeper instabilites.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 4

Cornices

Cornices are large and unsupported. They are more likely to fail with solar warming, and may trigger deeper slabs.

Extra caution needed around cornices with current conditions.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Apr 3rd, 2013 8:00AM