Avalanche Forecast

Issued: Mar 1st, 2014 8:00AM

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

Parks Canada catherine brown, Parks Canada

Loose, solar triggered avalanches are possible this afternoon on steep solar aspects. Minimize exposure to sun exposed slopes when solar radiation is strong.

Summary

Weather Forecast

A ridge of high pressure over the region gives one more day of sunny skies and cold temperatures.  This AM strong ridge top winds are blowing from the N/E.  Expect alpine temperatures around -18.  An area of low pressure starts to move into the region tonight bringing snow.  Flurries are forecast for Sunday, moderate snow is forecast for Monday.

Snowpack Summary

The Jan 28/Feb 10 PWL down 1-1.4m under a cohesive slab, is becoming more difficult to trigger but has high propagation propensity. Recently avy techs in the Bonney area had a whumph on this layer off the moraines and hard sudden planar results testing it at 2130m on a NE aspect. A surface sun crust has been found on steep solar aspects.

Avalanche Summary

We have observed solar triggered natural avalanche activity occurring from steep solar aspects, producing loose wet avalanches in the afternoon when the sun remains out. Numerous size 1.5-2.5 have been observed daily from steep southerly aspects along the highway corridor daily.

Confidence

Intensity of incoming weather systems is uncertain on Monday

Problems

Persistent Slabs

An icon showing Persistent Slabs
As this weak layer, buried down around 1 m, gains strength human triggered avalanches are still possible. Areas of concern are open, unsupported slopes, convex terrain and thin snowpack areas.
Choose conservative lines and watch for clues of instability.Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 4

Cornices

An icon showing Cornices
Cornices may destabilize by fluctuating temperatures.  If they fail, they could be the big trigger to initiate an avalanche in the deeper layers.
Pay attention to overhead hazards like cornices.Give cornices a wide berth when travelling on or below ridges.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Mar 2nd, 2014 8:00AM