Avalanche Forecast

Archived

Dec 13th, 2019–Dec 14th, 2019

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

Sea To Sky.

The recent snow has added load to buried weak layers and may still be reactive to human triggers. Conservative terrain selection is recommended.

Confidence

Moderate -

Weather Forecast

FRIDAY NIGHT - Cloudy with clear periods and isolated flurries / light northeast winds / alpine low temperature near -7

SATURDAY - Mainly cloudy with isolated flurries / light west winds / alpine high temperature near -7

SUNDAY - A mix of sun and cloud / light northwest winds / alpine high temperature near -9

MONDAY - Cloudy with sunny periods / southwest winds, 20-30 km/h / alpine high temperature near -4

Avalanche Summary

On Friday, there were reports of several explosives triggered and natural avalanches up to size 2.

On Thursday, there were several reports of human and explosives triggered avalanches up to size 2. Some of these avalanches stepped down to a weak crust/facet layer that was buried in mid November.

No new avalanches were reported on Wednesday.

Snowpack Summary

15-25 cm of recent fresh snow likely sits on a weak layer of feathery surface hoar in many areas, as well as sugary faceted snow in some areas. There is a crust from mid November that is now down approximately 45-100 cm. Recent snowpack tests have shown that the snow above the crust is weak and could produce avalanches. The snowpack is unusually shallow and weak for the Sea to Sky region. Snowpack depths range between 80-200 cm and taper quickly at lower elevations.

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.