Avalanche Forecast

Issued: Apr 15th, 2014 8:00AM

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

chris gooliaff, Parks Canada

Glacier.

A weak overnight freeze coupled with April showers will destabilize surface crusts at lower elevations.

Summary

Weather Forecast

A weak system rolls through Rogers Pass today/tonight, bringing light precipitation (less than 5cm), light to moderate westerly winds, and freezing levels around 1500m. Tomorrow will see a gradual clearing before the next disturbance on Thursday.

Snowpack Summary

Temperatures did not reach the freezing mark in the alpine until 1-2am, likely preventing a solid freeze of the surface. With light rain on the way, expect the crust to break down earlier in day. The snowpack on solar aspects is warming to near isothermal levels, but it stills awaits a dramatic warming to lose its structural integrity.

Avalanche Summary

Despite the warm alpine temperatures yesterday, only a small cycle of loose moist avalanches to size 2.0 on solar aspects was observed.

Confidence

Problems

Loose Wet

Low elevation areas are relying on a good overnight freeze to keep the snowpack together. There was not a strong freeze last night, so expect the surface crust to break down with light rain and the occasional glimpse of strong April sunshine.

Start and finish early before the surface crusts melt.Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Thin, variable slab is present in the alpine and tree-line. It appears to be bonding with the underlying interface, but some pockets in lee features may surprise a person.

If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Use caution in lee areas. Recent wind loading have created wind slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

Deeper persistent layers will require a large trigger to initiate, or a couple of people hitting a thin, weak spot in the snowpack.

Pay attention to overhead hazards like cornices.Be aware of the potential for full depth avalanches due to deeply buried weak layers.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Apr 16th, 2014 8:00AM