Avalanche Forecast

Issued: Mar 14th, 2018 4:36PM

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

Avalanche Canada mconlan, Avalanche Canada

Variable snow amounts are forecasted across the region, with the most expected on the eastern slopes.  Treat the hazard as higher if local snow amounts are substantially more than forecasted.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

THURSDAY:  Cloudy with snowfall, accumulation 10 to 20 cm, light westerly winds, alpine temperature -4 C, freezing level 1400 m.FRIDAY:  Cloudy with light snowfall, accumulation 5 cm, light easterly winds, alpine temperature -6 C, freezing level 1400 m.SATURDAY: Cloudy with snowfall, accumulation 10 to 15 cm, light to moderate northeasterly winds, alpine temperature -8 C, freezing level 1000 m.

Avalanche Summary

Widespread loose wet avalanches were noted on solar aspects to size 2 on Tuesday.  There was evidence of slab activity from sometime over the past week.  Some of the slabs stepped down to deep basal weaknesses.

Snowpack Summary

New snow will fall on a thick melt-freeze crust that exists on all aspects from recent warm temperatures and rain, except for possibly high elevation north.  On shady aspects at high elevations, new snow will likely fall on lingering wind slabs in lee features and loose dry in sheltered features.A weak layer of surface hoar buried mid-February exists in parts of the region around 50 to 80 cm deep.  The lower snowpack is weak with a combination of crusts and facets near the bottom of the snowpack that are widespread.

Problems

Storm Slabs

An icon showing Storm Slabs
Forecasted snowfall amounts are variable across the region, with the most expected on the eastern slopes.  Assess the snow accumulation and treat the hazard as higher if local amounts exceed 20 cm.
Keep an eye out for localized areas of enhanced snowfall, particularly on eastern slopes.Use caution in lee areas in the alpine and treeline. Storm snow may form touchy slabs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Deeply buried weak layers linger in the snowpack. These layers are most likely to be triggered from thin snowpack areas.
Pay attention to overhead hazards like cornices which could trigger deep persistent slabs.Avoid steep, rocky, and shallow snowpack areas where triggering deeper layers is more likely.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3.5

Valid until: Mar 15th, 2018 2:00PM