Avalanche Forecast

Issued: Jan 14th, 2015 4:00PM

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

ian jackson, Parks Canada

Banff Yoho Kootenay.

A classic, weak Rockies snowpack exists and doesn't inspire much confidence. Enjoy the beautiful weather and let's hope for a little new snow to refresh the ski quality for Friday.

Summary

Weather Forecast

A weak system will bring light snow starting Thurs PM. We should see 5-10 cm's by Friday night with a clearing trend for Saturday. With this system, we will also see strong alpine winds from the west. Temperatures will cool over the period but remain -5/-10 range at valley bottom.

Snowpack Summary

Wind slabs are present in many open areas above tree line. Below this, the snow pack is quite weak and facetted in most places. The Dec 18 crust/facet/surface hoar is facetting out but still a concern in deeper snowpack areas. The bottom half of the snow pack consists of facets and depth hoar with the early november crust facetting out.

Avalanche Summary

No new avalanche activity observed on a field trip to the Helen Shoulder area

Confidence

Intensity of incoming weather systems is uncertain on Thursday

Problems

Persistent Slabs

This layer is more touchy in deeper snowpack areas where it is more deeply buried (30 - 50 cm down) and at lower elevations where it is a rain crust/ surface hoar combination.

Choose conservative lines and watch for clues of instability.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Deep Persistent Slabs

In shallower snowpack areas (most of the region) the weak base of the snowpack persists and can be triggered in steep, rocky terrain features. Patience is a virtue with this problem, as bigger terrain may not be available until later this winter.

Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Jan 15th, 2015 4:00PM