Avalanche Forecast

Issued: Mar 4th, 2016 8:01AM

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

andrew jones, Parks Canada

Glacier.

Human triggered avalanches are likely in areas with wind slabs.

Summary

Weather Forecast

Cloudy periods mixed with sunny breaks and freezing levels climbing to 1800m. Ridge winds south 20km/hr gusting to 50km/hr. Another pacific front arrives early Saturday morning with up to 8cm of accumulation, strong southerly winds and freezing levels reaching 1800m. Precipitation intensifies Sunday with another front packing 20cm by Monday.

Snowpack Summary

60cm of storm snow overlies the Feb 27 layer, which is a variable crust on SE-W aspects, widespread surface hoar/stellars on shaded aspects, and in some areas a combination of both. Strong southerly winds have created additional loading and wind slabs on lee features. The Feb 10 surface hoar/ crust layer is down 100cm and is unreactive in tests.

Avalanche Summary

We received a report of a skier accidental size 1.5 avalanche on the moraines of The Dome Glacier, failing on a rapidly formed wind slab. 2 large size 3 natural avalanches were observed in the highway corridor, likely triggered during an strong wind even yesterday morning.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Wind Slabs

Ongoing strong southerly winds have created reactive slabs on lee features. Likely locations for these slabs are northerly aspects near ridge line and crossloaded ribs in valleys that channel the winds.

Use caution in lee areas. Recent wind loading has created wind slabs.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 - 2

Persistent Slabs

The Feb 27 crust/ surface hoar layer is down 50-60cm and is producing moderate results in stability tests. When triggered, this layer could propagate into a large avalanche. Dig down and test this layer before committing. It is easy to identify.

Ski short pitches and regroup in safe spots.Use caution on open slopes and convex rolls

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 3

Cornices

New snow and strong winds have contributed to cornice development. Warm temperatures and periods of sun may be enough to cause cornices to fail today. Cornice failures have potential to trigger persistent slabs on slopes below, with big consequences.

Minimize overhead exposure to cornices above.Extra caution needed around cornices with current conditions.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Mar 5th, 2016 8:00AM