Avalanche Forecast

Issued: Mar 14th, 2016 9:11AM

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

esharp, Avalanche Canada

Northwest Coastal.

Avoid steep, fat looking slopes and wind loaded features. They could be reactive to human triggering through the storm on Tuesday

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Tuesday

Weather Forecast

TUESDAY: Light snowfall brings up to 15cm overnight and 10 through the day, light to moderate southwesterly winds, 1000m freezing level. WEDNESDAY: Flurries with accumulations of up to 10cm. light westerly winds, 1000m freezing level. THRUSDAY: mainly sunny, light and variable winds, 1000m freezing level.

Avalanche Summary

Wind slab avalanches were triggered by explosive control on Sunday and lingering stubborn wind slabs may still be reactive to human triggering. Several natural and artificially triggered cornice collapses in the last week have caused large avalanches in the alpine. On Thursday of last week, a natural size 3.5 persistent slab avalanche was reported in Bear Pass. This avalanche occurred on a northwest aspect at 1350m elevation and released on the late-February surface hoar layer.

Snowpack Summary

New snow is falling onÂ widely wind effected old surfaces, burying wind pressed snow in exposed terrain and soft or hard slabs in lee features. Moist snow can be found at lower elevations and on solar aspects. A layer of surface hoar or facets down 70-100cm can be found in areas north of Stewart sitting below Marchs accumulated storm snow. Recent avalanche activity suggest that we may be approaching a critical load on this interface. An older crust/facet layer buried in early February can now be found around 80-120 cm below the surface, however, this layer has been dormant recently. Cornices are reported to be large and fragile.

Problems

Storm Slabs

New snow will settle into increasing reactive soft slabs in steep unsupported slopes and lee slopes through the day.

Be cautious as you transition into wind affected terrain.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

A layer of buried surface hoar or facets down 70-100cm has recently been reactive around Stewart and north. An old weak crust layer down over 1m remains a concern in the south of the region.

Dig down to find and test weak layers before committing to a big slope.>Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Mar 15th, 2016 2:00PM