Avalanche Forecast

Issued: Jan 18th, 2019 3:51PM

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

Avalanche Canada mconlan, Avalanche Canada

A bunch more precipitation is forecast for Friday night into Saturday, with changing freezing levels. Best to avoid avalanche terrain if you find 30 cm of snow or more accumulated, as the new snow likely won't bond well to underlying surfaces.

Summary

Confidence

Moderate - Freezing levels are uncertain

Weather Forecast

FRIDAY NIGHT: Cloudy with rain below 1500 m and snow above, accumulation 25 mm rain or 25 cm snow, strong to extreme southwest winds, treeline temperature 0 C, freezing level 1500 m.SATURDAY: Cloudy with light snowfall, accumulation 10 to 15 cm, strong southwest winds, treeline temperature -1 C, freezing level 1000 m.SUNDAY: Mostly cloudy, light north winds, treeline temperature -2 C, freezing level 1000 m.MONDAY: A mix of sun and clouds, light northwest winds, treeline temperature -3 C, freezing level 800 m.

Avalanche Summary

No recent avalanche observations were noted in the region. However, it is suspected that a natural avalanche cycle occurred Thursday night during the height of the storm. Another cycle may occur Friday night during the next storm.

Snowpack Summary

Upwards of 70 mm of water equivalent fell on Thursday night!  The freezing level appeared to be around 1300 m, so it is suspected that around 70 cm of snow fell at treeline and alpine elevations and the snowpack is rain-soaked below treeline. More snow is forecasted to fall on Friday night, with a freezing level at 1500 m and peaking around 1800 m but then dropping to 1000 m.At treeline and alpine elevations, all of this snow is falling onto sun and temperature crusts at most elevations and feathery surface hoar in sheltered and shaded areas. The new snow may not bond well to these surfaces. Below this, the snowpack is well-settled.

Problems

Storm Slabs

An icon showing Storm Slabs
Upwards of 70 cm of snow likely fell already above 1300 m, and rain below. More snow is expected Friday night but with rapidly changing freezing levels. Where snow falls, it will fall with strong winds and will likely be touchy to human traffic.
A good day to avoid avalanche terrain, especially if you find 30 cm or more of accumulated snow.At and below treeline, observe for bonding of the new snow before committing to avalanche terrain.At and below treeline, use caution in lee areas. Recent wind loading has created wind slabs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 3

Valid until: Jan 19th, 2019 2:00PM