Avalanche Forecast

Issued: Apr 12th, 2016 8:20AM

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

triley, Avalanche Canada

South Columbia.

Spring Conditions. Forecast new snow and wind will bring back that winter feeling in the mountains. Watch for new wind slabs that may not bond to the old hard surface.

Summary

Weather Forecast

Strong southwest winds and light snow overnight with freezing levels dropping down to 1500 metres. Light winds on Wednesday with a mix of sun and cloud, and a chance of some convective flurries. Freezing levels rising up to 1800 metres during the day. Freezing down to about 1400 metres by Thursday morning under mostly clear skies. Sunny with light northerly winds on Thursday and freezing levels rising up to 2000 metres. Mostly cloudy on Friday with scattered flurries.

Avalanche Summary

On Monday we had a report of a natural cornice fall size 2.5 from a north aspect at 2350 metres in the Selkirks. One natural size 3.0 avalanche was reported from a southeast aspect in the alpine that released at 2700 metres and ran about 1000 metres; this occurred in the southern Selkirks on Sunday. Most commercial operations have closed for the season, and data is becoming sparse.

Snowpack Summary

The snow surface is currently going through a typical spring melt-freeze cycle on all aspects and at all elevations, except possibly high true-north slopes which could be holding onto cold snow. The strength (thickness) of the surface crust and how quickly it breaks down during the day are important factors to focus on. Forecast wind and snow may bring back a winter feel above treeline for a day or two. Watch for new wind slabs that may not bond to hard old surface crusts.

Problems

Wind Slabs

Forecast new snow and wind may develop new wind slabs in the alpine and at treeline. New wind slabs may not bond well to the old surface crust.

Avoid freshly wind loaded features.>Be cautious as you transition into wind affected terrain.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Cornices

Forecast cloud, light snow, and cooler temperatures may reduce the likelihood of natural cornice falls.

Give cornices a wide berth when travelling on or below ridges.>Cornices become weak with daytime heating, so travel early on exposed slopes.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 4

Loose Wet

Forecast cooler temperatures and cloud cover should reduce the likelihood of loose wet avalanches. Lower elevations may be reactive during the heat of the day.

Be alert to conditions that change with elevation.>Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 13th, 2016 2:00PM