Avalanche Forecast

Issued: Apr 6th, 2018 3:27PM

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

mike.koppang, Alberta Parks

Kananaskis.

Freezing levels are forecast to climb to 2400m throughout the day on Saturday with light snowfalls. If the sun does poke through the clouds expect stability to decrease on solar aspects.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain on Saturday

Weather Forecast

Saturdays forecast is calling for flurries beginning in the afternoon and a warming trend with freezing levels climbing to 2400m later in the day.Â Some of this precipitation may fall as rain at lower elevations.Â Winds are forecast to be out of the south at 15-30km/hr.

Avalanche Summary

One thin sz 1 windslab was noted near Mt Chester in a steep crossloaded gully on a NW aspect.Â Otherwise no new avalanche activity was observed.

Snowpack Summary

Winds increased overnight on Thursday and stiffened up the previous windslabs that existed in the upper snowpack.Â These winds were variable so be on guard for these slabs as you approach ridgelines and around crossloaded features on all aspects.Â On friday forecasters encountered these slabs up to 15cm thick in one valley and non-existent in the next valley less than 1km away.Â A thin melt freeze crust also developed earlier in the week and can be found on all aspects except true north below 2000m and as high as 2400m on solar.Â Cornices are large so travel cautiously around them.Â

Problems

Wind Slabs

Wind slabs are being encountered along ridgelines in alpine terrain. These slabs do not extend far downslope but are present in lee terrain.

Evaluate unsupported slopes critically.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

The March 15th melt-freeze crust, buried 30-50cm on solar aspects, could be an issue on bigger slopes, particularly in the Alpine. Evaluate the snowpack for the presence/absence of this problem layer before committing to a terrain feature.

Avoid steep Southerly aspects.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Cornices

Cornices are large and looming over slopes at the moment. If the warm temperatures arrive cornice collapses could be a major concern. Keep an eye on the snow and the temps.

Give cornices a wide berth when travelling on or below ridges.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2.5

Valid until: Apr 7th, 2018 2:00PM