Avalanche Forecast

Issued: Apr 1st, 2012 4:00PM

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

mike.koppang, Alberta Parks

Kananaskis.

A skiers accidental sz 2.5 avalanche on Sunday in the Miners gully stepped down to ground indicating that the warm temps may be waking up some of the deep persistent weaknesses. Stability will decrease quickly when the sun comes out so use caution.

Summary

Confidence

Good

Weather Forecast

Isolated snowfalls are in the forecast for monday but forecasted amounts are not expected to be that significant. Temperatures will remain cool with daytime highs at 3000m around -10C. Strong solar radiation will deteriorate stability on solar aspects on Monday so use caution when travelling in these areas.

Avalanche Summary

Skier accidental sz 2.5 avalanche in the miners peak gully around 10:30am. Start zone was a crossloaded steeper feature on a NE aspect at 2300m. Crown was 100-160cm deep stepping down to ground in a few areas. Skier was carried for 300m but remained on surface. No Injuries.Numerous Na up to size 2.5 on S and SE aspects related to cornice collapses. Appeared the bed surface for the majority of these slides was the March 29th Temperature crust.

Snowpack Summary

Moist snow being encountered on solar aspects by as early at 10:00am. Moist snow on all aspects below 1900m by mid day. March 29th Temperature crust buried down 40-60cm with recent snow and touchy storm slabs are being observed on this layer. Winds spread storm and wind slabs developing in open wind affected terrain at treeline and above. Mainly on N and E aspects. Mid pack well settled. Valentines day surface hoar layer down 140-160cm and producing hard to no results.

Problems

Storm Slabs

Storm slabs up to 60cm deep are being encountered at treeline and above. Isolated natural avalanche up to size 2.5 were observed on Sunday with many avalanches failing on the temperature crust down 40-60cm. Slides may step down to deeper layers.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 5

Cornices

Strong solar radiation combined with recent new snow and strong SW winds were causing cornices to collapse over the past 24hrs. Cornices were triggerring avalanches to sz 2.5 on underlying slopes.

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

Elevations: Alpine.

Likelihood

Likely - Very Likely

Expected Size

1 - 4

Persistent Slabs

The February surface hoar is buried 120-150cm at treeline. This interface has been strengthening and becoming harder to trigger, but shallow snowpack areas are still a concern. Cornices or smaller avalanches could step down to this layer.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 6

Valid until: Apr 2nd, 2012 9:00AM