Avalanche Forecast

Issued: Dec 3rd, 2020 4:00PM

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

Stephen Holeczi,

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Overall we have had quality observations over the past few days. Watch for areas of wind slab in alpine areas, and be aware it is still possible to initiate a larger avalanche that can step down to the crust/facets. Enjoy the nice temperatures.

Summary

Weather Forecast

Another nice day Friday with inverted temperatures. Alpine temperatures will be just below freezing, and valley bottoms cooler. Alpine winds from the SW will pick up again into the strong range which should keep things relatively cool. No snow in the forecast.

Snowpack Summary

Variable surface conditions exist with hard wind slabs in exposed locations, softer snow in more sheltered areas and a surface crust on some solar aspects. The Nov 5 facet/crust combo is down 50-80 cm and producing hard to no results. This crust extends up to 2500 m on N aspects and higher on solar aspects. Snow depths at treeline are 70-140 cm.

Avalanche Summary

No new avalanches observed or reported in the forecast regions with good visibility.

Confidence

Due to the number and quality of field observations

Problems

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The Nov 5 crust has facets above and below it, and exists up to 2500m on shady aspects and higher on solar aspects. We have seen a few isolated avalanches on this layer so use caution in large steep terrain features during warm sunny periods.

  • Be aware of thin areas that may propogate to deeper instabilites.
  • Pay attention to overhead hazards like cornices which could trigger the deep persistent slab.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Wind Slabs

An icon showing Wind Slabs

These wind slabs are slowly bonding, but may still be a problem in steep alpine terrain where the surface looks wind affected.

  • If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Dec 4th, 2020 4:00PM