Avalanche Forecast

Issued: Jan 1st, 2016 4:00PM

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

Lisa Paulson, Parks Canada

Banff Yoho Kootenay.

Ice climbers be aware of the warmer temperatures aloft. There is potential for the hazard to rise quickly with increased avalanche activity mid-day on steep solar aspects.

Summary

Weather Forecast

A strong ridge of high pressure will dominate the region through the weekend bringing lots of sunshine and calm winds. Some models are not handling the inversion well, check our weather stations for current temperatures. Alpine temperatures will remain warm through the weekend with freezing levels up to 2300 m. Temperatures will drop Sunday night.

Snowpack Summary

A well settled snowpack with few weaknesses exists throughout the region. There is moist surface snow on steep solar aspects. Isolated wind slabs up to size 1.5 exist on leeward slopes at treeline and above from recent wind effect. Below 2000m, the Dec 3 layer of surface hoar and facets remains visible (down 35-70 cm), but is currently dormant.

Avalanche Summary

On Friday, loose snow avalanches to size 2 were observed on steep cliffy/gullied terrain with the sun affect. In the past few days, there have been a few natural and skier triggered windslabs up to size 1.5 at and above tree line, several natural cornice failures to size 2, and a rockslide triggered size 3 over Home Brew Ice Climb on Mt. Stephen.

Confidence

Timing or intensity of solar radiation is uncertain

Problems

Loose Wet

Ice climbers and skiers be mindful of loose snow avalanches to size 2 in steep cliffs/gullied terrain. The sun is triggering moist snow sluffs that entrain the dry facets or moist surface snow in its path.

Watch for clues, like sluffing off of cliffs, that the snowpack is warming up.

Aspects: North, North East, East.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Wind Slabs

Isolated windslabs exist at treeline and in alpine areas. It's hard to pin down exactly where these are, but several natural and skier triggered avalanches (up to size 1.5) have been reported in the past week.

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

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Jan 2nd, 2016 4:00PM