Avalanche Forecast

Issued: Feb 11th, 2016 4:00PM

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

Ian Jackson, Parks Canada

Banff Yoho Kootenay.

The conditions remain tricky. Conservative terrain choices are essential to manage the hazard. The quality of the overnight freeze and amount of solar radiation are big factors to watch for right now.

Summary

Weather Forecast

The warm weather we have been seeing the last few days is slowly coming to an end. We should get a better freeze Thursday night with temperatures dropping to -5 / -10 at valley bottom. On Friday, we should get a small pulse of snow (5-10cm's) with moderate SW winds and freezing levels to ~1800m. Saturday looks cooler with light precipitation.

Snowpack Summary

A 50-100 cm slab overlies the January 6th weak layer of surface hoar, facets and sun crust and snowpack tests indicate an unstable bond between the two. The lower snowpack is facetted and quite weak. Warm temperatures over the past 72 hours have triggered an avalanche cycle and left the surface snow affected by sun, temperature & wind crusts.

Avalanche Summary

There have been many large natural and explosive triggered avalanches in the last few days triggered by warm temperatures and solar radiation. A very close call on Twin Cairns in the Sunshine backcountry yesterday - a size 2.5 accidentally triggered took a skiier for a ride and partially buried the skiier.

Confidence

Freezing levels are uncertain on Friday

Problems

Persistent Slabs

Widespread natural and explosive triggered avalanche activity on this layer in the past few days. In thinner areas, avalanches are scrubbing down to ground. With the cooling temps, this should become less reactive, but is still worthy of respect.

Avoid areas with overhead hazard.Avoid paths that have not avalanched recently.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Loose Wet

If the forecasted overnight freeze and cloudy skies materialize, this may not be an issue. But if the temperatures are warm and the sun is shining, watch out!

Avoid ice climbs exposed to steep rocky terrain on solar aspects during the middle of the day.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Feb 12th, 2016 4:00PM