South Columbia

Rising avalanche danger: Time to reel in your terrain exposure.

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

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 fluctuating freezing levels, peaking around 1800 m. Snowfall: 10-15 cm on Saturday, 10-25 cm on Sunday, 20-35 cm on Monday. Locally heavier amounts are quite likely. For more details check out https://avalanche.ca/weather.

On Thursday, numerous small loose sluffs and soft slabs were triggered naturally and by skiers, 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.

Around 20-30 cm recent snow has fallen 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 wouldn't rule out the possibility of weak interfaces at higher elevations, especially crusts. Strong southerly winds are transporting snow onto lee slopes and creating deep wind slabs. 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.