Avalanche Forecast

Issued: Nov 17th, 2020 8:00AM

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

Chris Gooliaff,

A dramatic warm-up accompanied by strong S'ly winds may trigger a natural avalanche cycle today.

Choose conservative lines with limited exposure to overhead start zones.

Summary

Weather Forecast

WARM and WINDY today, then snowy Wed-Fri.

Today: rapid warming with Alp high of +5*C, FZL rising to 3000m, strong/extreme S'ly winds

Tonight: snow, 15-20cm, FZL dropping to 1500m, mod/strong SW winds

Wed: flurries, 10cm, FZL 1500m, light/mod SW winds

Thurs: flurries, 7cm, FZL 1100m, light/mod SW winds

Fri: flurries, 7cm, FZL 900m, mod SW winds

Snowpack Summary

30-60cm of snow overlies a widespread Nov 5 crust. This crust complex has weaker snow crystals (facets) above, below, and sandwiched in the middle...yes, ugly! Snowpack tests yesterday had sudden planar and/or collapses in these facets. The Nov 5th rain crust reaches as high as 2500m, while a sun crust is found higher on steep solar aspects.

Avalanche Summary

Natural avalanche activity has decreased, with a few isolated storm slabs noted from Tupper and Macdonald. However, a skier accidental with a full burial occurred Saturday up Connaught Creek, where the storm slab was initiated on the Nov 5th crust. If you observe an avalanche or notable conditions, consider sharing on the AvCan MIN site.

Confidence

Freezing levels are uncertain

Problems

Persistent Slabs

An icon showing Persistent Slabs

Wind and warmth will stiffen up the surface slabs, causing them to become more sensitive to human triggering.

  • 1011
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Valid until: Nov 18th, 2020 8:00AM