Avalanche Forecast

Issued: Jan 23rd, 2016 7:47AM

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

Avalanche Canada pmarshall, Avalanche Canada

A Special Public Avalanche Warning continues for this region. Conservative route selection and cautious decision-making is required.

Summary

Confidence

High

Weather Forecast

Sunday: Cloudy with sunny breaks and a chance of flurries. The freezing level is around 600-1000 m and winds are light from the S-SW. Monday: Cloudy with sunny breaks. The freezing level remains near 600-1000 m and winds are light from the S-SW. Tuesday: Cloudy with light to moderate snow. The freezing level rises to 1500 m and winds increase to moderate from the S-SW.

Avalanche Summary

Widespread natural slab and loose wet avalanches up to size 3 were reported throughout the region on Friday. Large slabs were observed on all aspects at all elevations (despite limited alpine observations due to poor visibility). There were also a report of a size 2 accidently skier-triggered slab that sympathetically released several other slabs up to size 2.5 on nearby slopes. Natural activity should slow down with cooler and drier weather this weekend; however, human triggering remains a concern in many areas (especially slopes between 1500 and 1800 m that didn't release naturally during the storm - even low angle slopes).

Snowpack Summary

This weeks "Pineapple Express Light" brought an average of 60 cm of new snow to the region. The snow line may have gone up to ridge top in the south, but only 1400-1600 m in the north. Expect dense new wind and storm slabs, and fresh cornice growth at upper elevations. Heavy loading from snow and rain, and the resulting avalanche cycle, has helped flush-out the mid- and early-January surface hoar/facet layers now down 80-120 cm deep. However, these layers are likely still intact and reactive in places and it may still be possible to trigger large slabs. The mid and lower snowpack is generally strong, with the exception of shallower snowpack areas that may be more faceted.

Problems

Persistent Slabs

An icon showing Persistent Slabs
Buried surface hoar remains primed for rider triggering, especially in the Northern part of the region where the snow line stayed below treeline during the recent storm. 
Be wary of slopes that did not previously avalanche - even on low angle terrain.>Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 5

Storm Slabs

An icon showing Storm Slabs
Recent storm snow may have settled and strengthened fairly quickly, but triggering soft slabs may still be possible in steep wind-loaded terrain. 
Choose well supported terrain without convexities.>Use ridges or ribs to avoid pockets of wind loaded snow.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Jan 24th, 2016 2:00PM