Avalanche Forecast

Issued: Dec 18th, 2016 4:00PM

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

deryl kelly, Parks Canada

Jasper.

Summary

Weather Forecast

Monday should see a continuation of the flurries we are expecting overnight. Accumulations are uncertain but could be as much as 10cm by morning with a further 6-10cm over the day on Monday. Sw winds continuing to blow, with gusts into the strong range. Warming up to -11 in the alpine which should feel downright balmy after the deep freeze.

Snowpack Summary

Wind press and scouring on the surface. Cold temps faceted the snowpack breaking down internal cohesion, especially below 2100ms. Where shallow, expect to be standing on the ground. Deeper HS areas have faceted above and below the Nov12 crust (45-90cm deep). Look for isolated buried SH layer down 10 to 15cms on E through N asp. in sheltered areas.

Avalanche Summary

1 x sz 2 Slab (-24hrs) on east aspect, 2100ms. Bottom 1/3 of feature called Snowboarder Slope on Parkers Ridge. Several size 1 to 1.5 loose snow avalanches observed at TL and above from steep rocky terrain.

Confidence

Intensity of incoming weather systems is uncertain on Monday

Problems

Loose Dry

Snow clinging to the mountain sides continues to shed from the steep terrain and sluffing and entrainment should be expected.

Avoid travelling on ledges and cliffs where sluffing may have severe consequences.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Wind Slabs

It's windy. So, expect to find windslab developing in the immediate Lee of slopes and ridge tops.

Use caution in lee areas. Recent wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

Although this layer has been dormant, it is still a concern and is widespread between 2100-2600m.

Be cautious in shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1 - 3

Valid until: Dec 19th, 2016 4:00PM