Kootenay Boundary Avalanche Forecast

Issued: Mar 18th, 2021 4:00PM

Fri Mar 19th Current Conditions
Alpine Moderate Treeline Low Below Treeline Low
Sat Mar 20th 2 Day Outlook
Alpine Moderate Treeline Low Below Treeline Low
Sun Mar 21st 3 Day Outlook
Alpine Moderate Treeline Low Below Treeline Low

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

New wind slabs may form over Friday at higher elevations.

Summary

Confidence

High -

Weather Forecast

A weak cold front will bring light amounts of snow and cooler temperatures on Friday.

THURSDAY NIGHT: 5-10 cm of snow with freezing level dropping from 2200 m to 1500 m, 30-50 km/h southwest wind.

FRIDAY: Scattered flurries with up to 5 cm of snow, 30-40 km/h southwest wind, treeline temperatures drop to -4 C and freezing level around 1500 m.

SATURDAY: Mix of sun and cloud, 20-30 km/h southwest wind, treeline temperatures around -5 C.

SUNDAY: Mostly cloudy, 20 km/h southwest wind, treeline temperatures around -5 C.

Avalanche Summary

No new avalanches were observed on Wednesday or Thursday, with the exception of small loose wet avalanches in steep sun-exposed terrain in the afternoon. In the coming days the main concern will be new snow forming isolated wind slabs.

Snowpack Summary

A weak cold front will bring 5-10 cm of new snow that may form new wind slabs at high elevations in lee terrain features. The new snow will overly a widespread melt-freeze crust, with the exception of northerly aspects at high elevations where some surface hoar has formed. Cornices are large and always have the potential of failing, particularly during daytime warming.

Deeper in the snowpack, a persistent weak layer from late January is buried around 80 to 150 cm and is composed of a combination of surface hoar, facets, and crusts. We haven't received a report of avalanche activity on this layer since late February and the likelihood of triggering this layer is currently low.

As always, best to avoid shallow, rocky areas where a weak and faceted snowpack may be found.

Terrain and Travel

  • Carefully evaluate steep lines for wind slabs.
  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Possible

Expected Size

1 - 1.5

New wind slabs may form on Friday as new snow and strong wind impact the region. Assess for the formation of slabs if you venture to steep, leeward terrain. 

Aspects:

North, North East, East, South East, North West.

Elevations:

Alpine, Treeline.

Valid until: Mar 19th, 2021 4:00PM

Forecast Trend

The latest forecast danger ratings, broken down to elevation. See how an elevation is trending.