Avalanche Forecast

Issued: Jan 19th, 2020 4:00PM

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

Avalanche Canada mconlan, Avalanche Canada

Email

A warming trend on Monday may make the recent snow touchier, with the deepest deposits found in lee terrain features near ridges.

Summary

Confidence

High -

Weather Forecast

SUNDAY NIGHT: Cloudy, moderate southwest wind, alpine temperature -2 C, freezing level rising to 1100 m.

MONDAY: Mix of sun and cloud with isolated flurries, accumulation 1 to 3 cm, moderate to strong southwest wind, alpine temperature -2 C, freezing level 1400 m.

TUESDAY: Cloudy with snowfall, accumulation 5 cm, light to moderate south wind, alpine temperature -5 C, freezing level 700 m.

WEDNESDAY: Morning snowfall then a mix of sun and cloud, accumulation 2 to 5 cm, light southwest wind, alpine temperature -7 C, freezing level 600 m.

Avalanche Summary

Many small to large (size 1 to 1.5) wind and storm slab avalanches were triggered by humans on Saturday. They occurred on all aspects and were generally 10 to 20 cm deep.

Persistent slab activity has tapered off in the past week, although there have been about one or two reports per week of large (size 3) explosive-triggered avalanches in alpine terrain.

Snowpack Summary

Strong southwest wind and around 10 to 20 cm of recent snow has formed new slabs, with the most reactive slabs being in lee terrain features at higher elevations. The slabs may become reactive at all elevations due to relatively warm air temperature on Sunday night into Monday.

A layer of surface hoar may still be found roughly 80-120 cm deep in the Selkirks and 120-160 cm deep in the Monashees. A facet/crust layer from late November may be found near the bottom of the snowpack. These layers appear to be unreactive at the moment, but could reappear as problems in the future.

Terrain and Travel

  • Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
  • Extra caution for areas experiencing rapidly warming temperatures for the first time.

Problems

Storm Slabs

An icon showing Storm Slabs

Around 10 to 20 cm of recent snowfall along with strong southwest wind and a warming trend will all work together to form new slabs. They will be deepest and potentially touchiest in lee terrain features in exposed terrain, particularly near ridges.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 20th, 2020 5:00PM