Avalanche Forecast

Issued: Apr 6th, 2013 3:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

Concern remains for instabilities related to the effects of solar radiation, warm daytime temperatures and rain at lower elevations. Also, watch for thin storm slabs in the alpine.

Summary

Confidence

Fair - Freezing levels are uncertain

Weather Forecast

Light flurries/rain showers will taper off Saturday night adding only a few cm's of new snow up high. Sunday may begin with a brief sunny period and then unsettled convective flurries are expected with no significant accumulations. Freezing levels on Sunday will be near 1800m, but cloudy conditions overnight Saturday will prevent a strong freeze.

Avalanche Summary

Very limited observations, but nothing new to report.

Snowpack Summary

Up to 15cm of recent snow at higher elevations has formed soft slabs in lee and cross-loaded terrain. Crusts remain widespread and vary considerably in thickness depending on aspect and elevation. Poor to little overnight recovery at lower elevations.

Problems

Loose Wet

As crusts melt with solar radiation, daytime heating and/or rain, wet avalanches are occurring. Be especially cautious in areas that have had little or no overnight freeze. Many slides are failing on the ground and involve the entire snowpack.

Watch for wet loose or slab activity with forecast rain and/or warm temperatures.>Avoid travelling on slopes which are becoming wet due to rain, warm temperatures, or sun.>

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

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 5

Cornices

Cornices are large and sagging. Cornice failures have triggered slabs on the underlying slopes in the two weeks. Be aware of overhead exposure especially during times of intense solar radiation or rain.

Extra caution needed around cornices with current conditions.>Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 5

Storm Slabs

Thin storm slabs are present in lee and cross-loaded features at higher elevations. The bond with the underlying layer is highly variable.

Avoid freshly wind loaded features.>Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Apr 7th, 2013 2:00PM