Archived

Avalanche Forecast

Apr 10th, 2019–Apr 11th, 2019

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Kootenay Boundary.

As soon as the sun comes out the surface snow will quickly become moist and increase the likelihood of loose wet avalanches.

Confidence

High -

Weather Forecast

WEDNESDAY NIGHT: Cloudy with clear periods / up to 10 cm snow accumulation / moderate northwest wind / freezing level 1100 mTHURSDAY: Mix of sun and cloud / light northwest wind / alpine high temperature -5 C / freezing level 1800 mFRIDAY: Mix of sun and cloud / light north wind / alpine high temperature -4 C / freezing level 1900 mSATURDAY: Cloudy / up to 10 cm snow accumulation / moderate southwest wind / alpine high temperature -4 C / freezing level 1700 m

Avalanche Summary

On Tuesday, a few human triggered wind/storm slabs up to size 1 were observed on sun affected slopes in the alpine. On Monday, only a few human triggered loose wet avalanches to size 1 were reported.On Sunday, there were reports of numerous natural, human and explosive triggered storm slab avalanches up to size 2.5 at treeline and in the alpine on all aspects (see this MIN report).

Snowpack Summary

10-35 cm of recent storm snow that fell over the weekend sits on a melt-freeze crust on all aspects, but on north facing slopes above 2000 m, where the recent new snow sits on dry snow and surface hoar (feathery crystals). The recent snow is bonding well with the underlying layers. Wind slabs can still be found in immediate lee features along ridge crests. Recent snowfall amounts taper quickly below treeline.

Avalanche Problems

Loose Wet

Warm temperatures and sun exposure will increase the likelihood of wet slab and loose wet avalanches.

Minimize overhead exposure to cornices above.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

Aspects: East, South East, South, South West, West.

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 1.5

Wind Slabs

Moderate northwest winds overnight might create shallow wind slabs in immediate lee features along ridge crests. Older wind slabs can still be found on northerly aspects in alpine lee features.

Use caution in lee areas and cross-loaded terrain near ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 1.5