Avalanche Forecast

Issued: Feb 16th, 2016 4:00PM

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

Avalanche Canada ian jackson, Avalanche Canada

Many close calls in neighboring bulletin regions over the past few days give pause for thought. Stick to conservative terrain and there is some great skiing to be had right now!

Summary

Weather Forecast

The jet stream is over us so expect to get regular snow throughout the week. The next storm will come in on Wed PM and we should see continuous light snow accumulating to 10-20 cms by Friday PM. Freezing levels are warming to 1500m on Wed and spiking to 2000m on Thursday before lowering on Friday. Alpine winds will be moderate to strong W/SW.

Snowpack Summary

Fresh windslab and rapid cornice growth is occurring with 20- 40 cm of recent snow and moderate to strong W winds. A 60-130 cm slab overlies the January 6th weak layer of surface hoar (below 2000m), facets and sun crust. This layer is slowly breaking down but still giving hard sudden planar results in test pits. The lower snowpack is well settled.

Avalanche Summary

No new avalanches observed or reported on Tues in Little Yoho. Forecasters on Mt Field on Tuesday saw evidence of a cycle 2-4 days old. Multiple size 2-3 avalanches failing on the Jan 6th layer in steep alpine terrain, often with a cornice trigger. Additionally, the Monarch slide path on Mt Field ran naturally size 2.5 within the last 48 hours.

Confidence

Freezing levels are uncertain on Thursday

Problems

Persistent Slabs

An icon showing Persistent Slabs

60-130 cm of snow overlies the Jan 6th layer of surface hoar, sun crust and facets and there have been many avalanches on this layer over the last week. Snowpack tests are giving hard sudden planar results and it has been less reactive below treeline

  • Avoid paths that have not avalanched recently.
  • Dig down to find and test weak layers before committing to a line.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

An icon showing Wind Slabs

Be mindful of cross loaded features and the lees of ridges where fresh windslabs 30-60 cm thick have recently formed. If triggered, there is potential to step down to the persistent weak layer and to ground in thin areas.

  • Use caution in lee areas. Recent wind loading has created wind slabs.
  • If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Feb 17th, 2016 4:00PM