Avalanche Forecast

Issued: Mar 3rd, 2021 4:00PM

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

Deryl Kelly,

Jasper.

http://www.pc.gc.ca/apps/links/goto_e.asp?destination=http://www.avalanche.ca/spaw/2021-03-03-special-public-avalanche-warning

Increasing temperatures and strong solar effect is forecast. This first big warm-up of the season will destabilize the snowpack.

A Special Avalanche Warning is in effect immediately, through Saturday.

Summary

Weather Forecast

Isolated warming on all solar aspects!

Overnight: Mainly cloudy. Alpine temperature: Low -7 °C. Ridge wind SW15-35 km/h. Fzl valley bottom.

Thursday: Cloudy with sunny periods. Alpine temperature: High -3 °C. Ridge wind SW15 km/h gusting to 45 km/h. Fzl 1900 m

Friday: Flurries. Accumulation: 6 cm. Alpine temperature: Low -6 °C, High -4 °C. Fzl 1800 m

Snowpack Summary

Snowpack morphing from cold/dry, to warm/moist spring conditions. Top 5-15cm moist snow over a supportive mid-pack in the Icefields. Windward aspects have been heavily stripped of snow. Highly variable snowpack across the region, with shallow areas failing at the faceted base, while deeper regions have a strong bridge over a weak base.

Avalanche Summary

Areas surrounding the Sunwapta, Gong, and Mushroom Peak region seem to be the most sensitive to natural triggers. Most natural observations have occurred in that zone.

Confidence

Timing or intensity of solar radiation is uncertain on Friday

Problems

Loose Wet

Afternoon sun is packing a punch on lower elevation, SW through W slopes. Ice climbers: be extremely cautious. Overhead hazards can catch sun early.

If triggered the loose wet sluffs may step down to deeper layers resulting in large avalanches.
Use extra caution on solar slopes or if the snow is moist or wet.

Aspects: South, South West.

Elevations: Treeline, Below Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Wind Slabs

Continued wind slab development is expected with overnight snowfall and moderate SW winds.

Wind slabs in the alpine and exposed treeline features have the potential for wide propagations across connected features.

Be aware of the potential for wide propagations due to the presence of hard windslabs.
If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Deep Persistent Slabs

Caution in thin facetted snowpack areas where triggering is more likely. This is a low probability but high consequence problem.

Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Mar 4th, 2021 4:00PM