Avalanche Forecast

Issued: Apr 10th, 2019 4:42PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Loose Wet and Wind Slabs.

ldreier, Avalanche Canada

North Columbia.

As soon as the sun comes out the surface snow will quickly become moist and increase the likelihood of loose wet avalanches. Wind slabs might still be sensitive to human triggering.

Summary

Confidence

High -

Weather Forecast

WEDNESDAY NIGHT: Cloudy with isolated flurries / up to 5 cm accumulation / light northwest wind / freezing level 900 mTHURSDAY: Mix of sun and cloud with isolated flurries / light northerly wind / alpine high temperature -5 C / freezing level 1700 mFRIDAY: Mix of sun and cloud / trace of snow / light westerly wind / alpine high temperature -5 C / freezing level 1700 mSATURDAY: Cloudy / 5-10 cm of snow accumulation / moderate southwest wind / alpine high temperature -5 C / freezing level 1600 m

Avalanche Summary

On Tuesday, several natural, human and remote triggered storm/wind slab avalanches 20-40 cm deep and up to size 2.5 were observed on north and east aspects. Several natural wet slab and loose wet avalanches up to size 2.5 were reported from south and west aspects (see a MIN report from Glacier National Park here). On Monday, several natural and human triggered storm slab avalanches up to size 2.5 were reported on west, north and east aspects in the alpine. A few natural and human triggered wind slabs to size 1.5 were reported from immediate lee features in the alpine. Several natural loose avalanches up to size 2.5 were observed on northerly aspects at treeline and in the alpine.

Snowpack Summary

15 to 40 cm of recent storm snow sits on a melt-freeze crust on all aspects except for north slopes above 2000 m, where it sits on dry snow and surface hoar (feathery crystals) in some areas. On northern aspects the new snow is slowly bonding and humans might still trigger storm slab avalanches. Strong southwest winds on Monday created isolated wind slabs in lee features at treeline and in the alpine. Recent snowfall amounts taper quickly below treeline. Snow is disappearing rapidly at lower elevations.

Problems

Loose Wet

Expect the snow surface to become moist and the likelihood of loose wet avalanches to increase on sun exposed slopes as soon as the sun is coming out.

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, North West.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Wind Slabs

40 cm of storm snow is slowly bonding with the underlying layers. Old wind slabs can be found in immediate lee features. Wet slab avalanches might be triggered by humans on sun affected slopes.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 11th, 2019 2:00PM