Avalanche Forecast

Issued: Mar 9th, 2018 4:36PM

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.

jsmith, Avalanche Canada

Lizard-Flathead.

Sunshine and warming will increase hazard throughout the weekend. Natural loose wet avalanches are expected on steep south facing slopes and lingering storm slabs reactive to human triggers.

Summary

Confidence

High -

Weather Forecast

SATURDAY: Sunny / Light southwesterly ridgetop winds / Freezing level rising to around 1500 m.SUNDAY: Mostly sunny / Light southwesterly ridgetop winds / Freezing level rising to around 2000 m.MONDAY: Sunny / Light southwesterly ridgetop winds / Freezing level rising to around 2300 m.

Avalanche Summary

Several size 2 natural storm slab avalanches and numerous human triggered storm slabs up to size 1.5 on all aspects and elevations were observed near Fernie on Thursday.

Snowpack Summary

20-30 cm of new snow is sitting on a sun crust on solar aspects. Cornices are large and prone to failure over the weekend caused by forecast sunny skies.In the upper to mid snowpack, a surface hoar or facet layer buried mid-February is now 80 to 110 cm below the surface on sheltered northerly aspects. Deeper in the snowpack, the widespread mid-December and late November weak layers are composed of a combination of crusts and sugary facets which are down 200-300 cm.Â These layers have been dormant but may be awoken by the warm and sunny weather over the weekend or by a large trigger such as a falling cornice.

Problems

Storm Slabs

Storm slabs are expected to still be reactive to human triggers on Saturday.

Use caution when transitioning into wind affected terrain.Use small slopes with low or no consequence to test the bond of the new snow.Avoid terrain traps where small avalanches can have high consequence.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Loose Wet

Forecast sunshine is expected to trigger loose wet avalanches on steep south facing slopes.

Avoid terrain traps such as gullies and cliffs where small avalanches can have high consequence.Watch for signs that the snow is heating up such as pin-wheeling and point-releases below cliffs.Start early to stay off south facing slopes during the heat of the day.

Aspects: North, North East, East, South East, South.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Valid until: Mar 10th, 2018 2:00PM