Avalanche Forecast

Issued: Jan 24th, 2015 9:00AM

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

Avalanche Canada jlammers, Avalanche Canada

Recent snowfall totals vary dramatically across the region. Pay close attention to localized conditions.

Summary

Confidence

Fair - Intensity of incoming weather systems is uncertain

Weather Forecast

A steady pacific moisture stream is aimed at the North Coast, although the track of the system suggests the bulk of the precipitation will initially fall just to the south of the region. Sunday: Between 5 and 10cm of snow at higher elevations / Extreme southwest winds / Freezing levels at 1400m Monday: Up to 15cm of snow at higher elevations / Strong southwest winds / Freezing levels at 1300m Overnight Monday and Tuesday: 10-15cm of snow / Strong southwest winds / Freezing levels at 800m

Avalanche Summary

Periods of heavy snow or rain, strong ridge winds, and warming will probably tip off a natural avalanche cycle in parts of the region. We could see wet activity at lower elevations with storm/wind slabs where snow accumulates. There is also potential for deep persistent weaknesses to be overloaded producing isolated very large and deep slides.

Snowpack Summary

Continued snowfall has contributed to ongoing storm slab development. Warm temperatures have promoted rapid slab settlement, while rain has created wet loose surface snow at lower elevations. Southwest winds continue to build slabs on leeward slopes with cornices overhead in exposed treeline and alpine terrain. A recent report from the Ashman area mentioned whumpfs and other signs of instability associated with roughly 30 cm of recent snow rapidly settling into a slab under warm temperatures and significant wind. A surface hoar layer buried at the start of January may be around 40-70 cm deep now. In the mid-pack, a crust weakness buried in mid-December seems to be unreactive for the time being. Near the base of the snowpack is the crust-facet combination buried in November that could remain problematic, especially in shallower snowpack areas with heavy loading and warming.

Problems

Storm Slabs

An icon showing Storm Slabs
Continued snowfall, warming and extreme winds will add to the destructive potential of a developing storm slab. Storm loading may also trigger persistent weaknesses deeper in the snowpack.
Be alert to conditions that change with elevation.>Stay off recent wind loaded areas until the slope has had a chance to stabilize.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Wet Slabs

An icon showing Wet Slabs
Watch for destructive wet slab avalanches at lower elevations where precipitation has fallen as rain, especially in areas where saturated snow overlies crusts or other weak layers. Loose wet avalanche are also a concern in steep terrain.
Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.>Be alert to conditions that change with elevation.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Heavy loading from snow and/or rain could trigger deep persistent weaknesses and produce isolated very large avalanches.
Be aware of the potential for full depth avalanches due to deeply buried weak layers.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 6

Valid until: Jan 25th, 2015 2:00PM