Avalanche Forecast Northwest Coastal

Date Issued: Valid Until:

Avalanche Canada cgarritty, Avalanche Canada

Avalanche Forecast

Tue Feb. 12th ยท 5:20PM

Alpine

Danger Ratings Low

Treeline

Danger Ratings Low

Below Treeline

Danger Ratings Low
Wind Slabs Wind Slabs

Alpine

Danger Ratings Low

Treeline

Danger Ratings Low

Below Treeline

Danger Ratings Low

Alpine

Danger Ratings Low

Treeline

Danger Ratings Low

Below Treeline

Danger Ratings Low
Winds should ease up a bit on Wednesday, but the damage is done. The snow surface is a wind-abused mess. Maintain normal cautions and watch for small slabs in steep terrain that formed more recently.

Confidence

High -

Weather Forecast

Tuesday night: Clear periods with increasing cloud. Light north winds.Wednesday: Cloudy with sunny periods. Light northwest winds. Alpine high temperatures around -8.Thursday: Cloudy with sunny periods. Light east or northeast winds. Alpine high temperatures around -11.Friday: Sunny with cloudy periods. Light northeast winds. Alpine high temperatures around -16.

Avalanche Summary

No new avalanches have been reported over the past couple of days.Reports from Sunday showed a continuation of small (size 1), thin wind slabs releasing with ski cutting on northwest to west aspects. In the north of the region near Ningunsaw, an older, large (size 3) natural deep persistent slab was observed on a steeper, crossloaded feature at 1700 metres. The slab depth ranged from 50 cm to 2 metres as a shallower wind slab release stepped down to the weaker basal snowpack that exists in this part of the region.

Snowpack Summary

In most areas, the upper snowpack is composed of successive layers of aging, wind affected storm snow layers. The top layer of this snow has been faceting (becoming sugary) under the influence of recent cold temperatures at all elevations. Limited sheltered areas at lower elevations may still hold pockets of around 40 cm of lower density snow which will overlie a thick melt-freeze crust at and below treeline. This crust now presents on the surface in many wind-exposed areas.In the south of the region, the remainder of the snowpack is well-settled.Around Bear Pass and in the north of the region a few weak layers may still be preserved within the middle and lower half of the snowpack. These include layers of surface hoar at around 50 cm deep, 70 to 100 cm deep, and a layer of sugary faceted snow around 200 cm deep. These layers are a concern in thinner snowpack areas at higher elevations where thicker, bridging layers of old storm snow and crust may be absent.

Problems

Wind Slabs

Wind Slabs

Outflow winds from the southeast and northeast have been scouring surface snow and packing it into thin wind slabs on lee slopes. Most slabs have likely stabilized, but small recent slabs may remain reactive to triggering in steep leeward features.

Look for patterns of wind loading as you transition into wind affected terrain.Be careful around wind loaded pockets near ridge crests and roll-overs.

Aspects: North, South, South West, West, North West.

Elevations: Alpine.

Likelihood

Possible - Unlikely

Expected Size

1 - 1.5