Avalanche Forecast

Issued: Mar 27th, 2013 3:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

Spring conditions are here. Intense solar radiation and daytime heating will increase avalanche danger each day. It's a good time for longer tours but keep a close eye on overhead terrain.

Summary

Confidence

Good

Weather Forecast

Thursday should be mostly sunny with continued light winds. Alpine temperatures near -8, but freezing levels will climb to at least 2200m. Very slight chance of precipitation on Wednesday night.

Avalanche Summary

Numerous solar triggered sluffs up to size 1.5 were observed today on steep South aspects.

Snowpack Summary

The snowpack continues to settle. Sun crusts are present on solar aspects. These crusts are breakable in the morning and are melting each afternoon with intense solar radiation and warm temperatures. Cornices are large in many areas and are suffering from intense solar radiation. Wind slabs are still a concern in steep, convex and unsupported terrain, especially on northerly aspects at higher elevations.

Problems

Persistent Slabs

Buried wind slabs are a concern in steep, convex and unsupported features. These slabs are hidden under previous snowfalls so take time to dig down and evaluate their presence and sensitivity. Recent compression tests show moderate to hard results.

Choose well supported terrain without convexities.>Avoid open slopes with any steepness over 40 degrees.>Avoid convexities or areas with a thin or variable snowpack.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 5

Cornices

Cornice failures continue to be a theme, with several failures triggering slab avalanches in the past week. Be aware of overhead exposure especially during times of intense solar radiation.

Cornices become weak with daytime heating, so travel early on exposed slopes.>

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 5

Loose Wet

Steep solar aspects have been producing loose wet avalanches in the past several days as intense solar radiation and daytime heating breaks down the sun crust.

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

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

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 4

Valid until: Mar 28th, 2013 2:00PM