Avalanche Forecast

Issued: Jan 12th, 2018 3:30PM

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

Avalanche Canada jlammers, Avalanche Canada

If the sun comes out on Saturday, the Avalanche Danger may rise to HIGH.

Summary

Confidence

Moderate - Timing or intensity of solar radiation is uncertain

Weather Forecast

Saturday: Overcast with possible sunny breaks in the afternoon / Light and variable winds / Freezing level rising to 2500mSunday: Clear skies / Light and variable winds / Freezing level at 3200mMonday: 10-20mm of precipitation / Moderate southerly winds / Freezing level at 2000m

Avalanche Summary

On Wednesday we received a fantastic MIN report of a size 1.5 skier-triggered wind slab in the alpine. You can see it here. This report shows just how different the conditions are between the North Shore and the Squamish area. On Friday, we received reports of new storm snow failing on older loose, dry storm snow on a crust. The avalanches were relatively small, but were failing in surprisingly low angle terrain and entraining significant mass. Looking forward, expect a new round of storm slab activity in response to new snow and strong winds on Friday night. At elevations where rain falls, loose wet avalanche will also be possible.

Snowpack Summary

Strong southeast winds and snowfall on Friday are expected to form dense storm slabs in exposed high elevation terrain while rain is forecast to saturate the upper snowpack at lower elevations. The newly developed storm slab may be surprisingly touchy as recent reports from the North Shore indicate that it may overly a mix of loose, dry storm snow on top of a thin crust. This combination has proven to be reactive in surprisingly low-angle terrain. About 60cm below the surface you'll also find thick melt-freeze crust that formed as a result of heavy rain at the beginning of the week. The bond at this interface will likely gain strength over time; however, professionals are monitoring this layer as it has the potential to produce large avalanches in isolated terrain.The snowpack depth at 1000 m is about 150 cm and many early season hazards are still present.

Problems

Storm Slabs

An icon showing Storm Slabs
New snow and wind on Friday is expected to form new storm slabs and increase the avalanche danger. The new snow may be especially touchy due to underlying crusts. If the sun comes out on Saturday, expect the avalanche danger to rise significantly.
Be cautious as you transition into wind affected terrain.Be alert to conditions that change with elevation.The new snow may require several days to settle and stabilize.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Loose Wet

An icon showing Loose Wet
At elevations where precipitation falls as rain, the upper snowpack will become saturated and loose wet avalanches may occur in steep terrain. Loose wet avalanches can travel long distances and entrain mass quickly.
Use extra caution on slopes if the snow is moist or wet.Minimize exposure to steep slopes on warm or sunny days.Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Jan 13th, 2018 2:00PM