Avalanche Forecast

Issued: Dec 3rd, 2015 7:40AM

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

Avalanche Canada pgoddard, Avalanche Canada

The game is changing quickly as new snow has buried a super-touchy weak layer. Time to reel in your terrain exposure.

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

A series of storms is coming in quick succession over the next few days. Disagreement between weather forecast models is making it hard to pin down specifics, but you can expect snow, south to south-west winds and freezing levels rising to around 1700 m. Today's best guess for snow is around 2cm on Friday, 10-20 cm on Saturday and 15-20 cm on Sunday. I wouldn't bet my house on it. For more details check out http://www.avalanche.ca/weather.

Avalanche Summary

On Thursday, skiers triggered numerous small loose sluffs and soft slabs, even from a distance away. Their reactivity was described as electric. As the snow load builds, I expect a more widespread cycle to kick off. A naturally triggered size 2 slab failed on a SE aspect at 2000 m on Wednesday.

Snowpack Summary

Recent snow (around 25 cm at the time of writing) is building up over a variety of old surfaces including wind-stripped north aspects, hard wind slabs, facets, sun crusts and/or large-sized surface hoar. Of most immediate concern is a crust/surface hoar interface that is already super-reactive. Reports suggest that the surface hoar exists up to about 2000 m and the crust maybe found on all aspects. I certainly wouldn't rule out the possibility of weak interfaces at higher elevations, especially as crusts exist well into the alpine. Storm slabs are likely to develop all over the place with winds and temperature changes affecting the new snow.Deeper in the snowpack, surface hoar interfaces that were key players in November seem to be inactive. In the highest and shadiest spots, a crust/facet interface may be found near the ground, but is not generally considered a major concern at this time.

Problems

Storm Slabs

An icon showing Storm Slabs
Snow is building up over a very touchy weak layer and building storm slabs that are sensitive to human triggering.
Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Dec 4th, 2015 2:00PM