Avalanche Forecast

Issued: Apr 11th, 2015 8:09AM

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

mike.koppang, Alberta Parks

Kananaskis.

Spring Avalanche Danger is variable and can range from Low to High. Travel early in the day is recommended as conditions can change rapidly due to daytime warming. Pay attention to the integrity of crusts formed overnight and rising temps. Synopsis

Summary

Confidence

Fair - Timing or intensity of solar radiation is uncertain on Sunday

Weather Forecast

Sunday will be a mix of sun and cloud with a chance of some convective flurries throughout the day. Alpine temperatures will be around -9C and winds will be moderate out of the west. Freezing levels should be around 1900m. When the sun does come out, stability will decrease quickly so pay close attention the the aspect you are travelling on or underneath on your way home.

Avalanche Summary

A few loose dry avalanches were observed from steeper terrain on Saturday. Also there was a report of a sz 2.5 on a N aspect near the "Sharks tooth" peak in the commonwealth area. This avalanche was likely triggered by a cornice collapse.

Snowpack Summary

Over the past 24hrs up to 15cm of new snow has fallen with moderate NW winds. This new snow will form thin new storm slabs and bury the previous windslabs that we were talking about. Cornices are also large and there have been reported failures of late with the large loads triggering slabs on the underlying slopes. The basal facets have not been active in some time but as temperatures warm up, we may start to see them become more active. Temperature, Aspect and time of day are all relevant at this time. The quality of the freeze overngiht will play a large role in regards to stability. When the snowpack is in its frozen state, the avalanche danger is relatively low-moderate. As it begins to melt, it will become less stable and eventually, the danger may increase to high. Solar aspects will see the biggest changes, especially in steeper, thin, rocky terrain. Northern aspects still have dry powder snow and a generally winter snowpack. Evaluate the terrain and overhead hazard as you travel. To review common spring avalanche problems go here

Problems

Storm Slabs

Watch for these new slabs in immediate lees in Alpine terrain.

Caution in lee and cross-loaded terrain near ridge crests.>

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

Elevations: Alpine.

Likelihood

Likely

Expected Size

1 - 2

Wind Slabs

Buried windslabs in alpine terrain. These developed earlier in the week when winds increased out of the SW.

Be cautious as you transition into wind affected terrain.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Cornices

Cornices may fail with daytime warming and trigger slabs on underlying slopes or possibly awaken the basal facets that haven't been active in a long time causing a full depth avalanche.

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

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Apr 12th, 2015 2:00PM