Avalanche Forecast

Issued: Mar 19th, 2016 8:00AM

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

andrew jones, Parks Canada

Glacier.

There are several complex avalanche problems that very with aspect and elevation. Be aware of changing hazards as you move through terrain.

Summary

Weather Forecast

A mix of sun and cloud today with freezing levels reaching 1800m. Alpine temperature high of -1, although expect warmer temps on solar aspects if the sun shines through. Winds remain light form the south. Freezing levels continue to rise this weekend, peaking at 2700m on Sunday with light rain.

Snowpack Summary

Expect a surface crust on solar aspects. 30 to 50 cm of settling storm snow remains unconsolidated in shaded areas and sits over a crust on solar aspects. Weak layers from February are down 70-120cm and are of most concern on solar aspects. Touchy winds slabs and deep loading exist on lee features in the alpine. Cornices are large and touchy.

Avalanche Summary

We received reports of several natural avalanches in the Rogers Pass backcountry. Avalanches were triggered on solar aspects and ranged from loose point releases to storm slab releases.

Confidence

Timing or intensity of solar radiation is uncertain

Problems

Cornices

Occurrences of cornice failures triggering persistent weak layers are on the rise. Daytime warming and solar radiation increase the sensitivity of this avalanche problem. Avoid slopes (and run-out zones) that are subject to overhead hazard.

Even small cornice falls may trigger larger avalanches.Give cornices a wide berth when traveling on ridges.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

2 - 3

Persistent Slabs

Buried crusts are creating persistent instabilities on solar aspects. Storm snow sits on a crust down 30-50cm. February crust is down 80-120cm and still has surface hoar crystals on top in some places. Locate and test these layers before committing.

Minimize exposure to steep, planer south facing Alpine slopesChoose well supported terrain without convexities.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Loose Wet

Intense spring sun coupled with rising freezing levels can trigger loose wet avalanches with the potential to run far. This is a classic "step-down" scenario where a small releases could trigger storm slabs and buried persistent weak layers.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: North, North East, East.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Mar 20th, 2016 8:00AM