Avalanche Forecast

Issued: Apr 25th, 2014 9:25AM

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

mbender, Avalanche Canada

South Columbia.

Avalanche danger can rise quickly with daytime warming and solar radiation. Be aware of changing conditions and overhead hazards.

Summary

Confidence

Poor - Due to the number of field observations

Weather Forecast

Saturday: Flurries / Light southerly winds / Freezing levels 1800m.Sunday: Flurries /Light southwesterly winds / Freezing levels 1800-2000m.Monday: Mix of sun and cloud with isolated flurries / Light southwest winds / Freezing Level 1800m.

Avalanche Summary

Expect loose wet avalanches in steep terrain if it is raining or during sunny periods, especially if the sun or rain is affecting fresh snow. Spring squalls may bring locally heavy precipitation and new storm or wind slabs may develop in higher terrain if you see significant new snow accumulation. Cornices collapses have been reported during periods of daytime warming. Occasionally these heavy triggers have caused large deep slab avalanches on the slopes below.

Snowpack Summary

This is a broad summary of conditions is based on limited field data and should be supplemented with local observations to help assess avalanche danger.Over the past week or so the Columbias have seen moderate amounts of new snow mixed with showers or periods of rain below 1600-1800 m. Southerly winds have likely formed pockets of wind slab at higher elevations in lee of ridges and terrain features. The upper snowpack generally consists of layers of moist and/or dry snow mixed with several well bonded crusts. Below 1300-1500 m most areas are likely below threshold for avalanches depending on aspect. The mid-March sun crust/surface hoar layer down 50-80cm and the early-March crust/facet/surface hoar layer down around 80-120cm seem to be inactive. The mid-February crust/facet/surface hoar combo is typically down 150 - 200cm. Human triggered avalanches on this layer are unlikely. Larger triggers such as cornice fall, a smaller avalanche in motion or prolonged warming could wake this layer up, resulting in very large and destructive avalanche.

Problems

Wind Slabs

Moderate winds have redistributed recent snow and wind slabs may be found in lee 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

Loose Wet

Expect loose wet avalanches in steep terrain if it is raining or during sunny periods, especially if the sun or rain is affecting fresh snow.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Apr 26th, 2014 2:00PM