Avalanche Forecast

Issued: Mar 18th, 2017 8:08AM

The alpine rating is high, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Storm Slabs and Persistent Slabs.

Parks Canada chris gooliaff, Parks Canada

Heavy snowfall and rising temperatures today will cause a spike in avalanche danger. Choose a very conservative route with no overhead hazard.

Summary

Weather Forecast

A low pressure system will track across the area today, bringing another 15cm of snow with winds gusting to 80km/h from the SW. Freezing levels are expected to hit 1800m around noon, then drop rapidly tonight with the passage of the storm. Flurries and alpine high's of -11*C on Sunday.

Snowpack Summary

This week's storm brought warm temps, intense precipitation and strong S winds. This has left touchy storm and wind slabs above tree-line and a breakable crust with moist/wet snow below tree-line. Weak interfaces in the upper snowpack are still easily trigged by human loading. The late Feb crust interface is now down 1-1.5m.

Avalanche Summary

One natural avalanche was reported from Cheops North 5 yesterday, while another size 3.5+ in Loop Brook ripped out deep persistent layers on moraines. The powder cloud was observed coming across the normal up-track towards Balu Pass. Several natural avalanches to size 2.5 were also observed in the highway corridor.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Storm Slabs

An icon showing Storm Slabs
Heavy precipitation combined with wind and warm temperatures have formed reactive storm slabs at all elevations. Added snowfall from last night and today will see these slabs become more active once again.
If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.The new snow will require several days to settle and stabilize.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 3

Persistent Slabs

An icon showing Persistent Slabs
Persistent deep layers made a triumphant return during our most recent avalanche cycle and they remain a cause for concern. As surface instabilities fail, avalanches can easily step down to weak layers from late February.
Use conservative route selection, choose moderate angled and supported terrain with low consequence.Watch for whumpfing, hollow sounds, and shooting cracks.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

3 - 4

Valid until: Mar 19th, 2017 8:00AM