Avalog Join
Archived

Avalanche Forecast

Mar 7th, 2019–Mar 8th, 2019
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
1: Low
The avalanche danger rating at treeline will be low
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
1: Low
The avalanche danger rating in the alpine will be low
Treeline
1: Low
The avalanche danger rating at treeline will be low
Below Treeline
1: Low
The avalanche danger rating below treeline will be low

Regions: North Columbia.

Fresh storm slabs may be reactive to human triggering. Watch for signs of instability such as whumphing, cracking and recent avalanches.

Confidence

Moderate -

Weather Forecast

THURSDAY NIGHT - Mainly cloudy with isolated flurries, up to 5 cm / west winds 20-40 km/h / alpine low temperature near -11FRIDAY - Mainly cloudy with isolated flurries, 5 cm / west winds 10-20 km/h / alpine high temperature near -9SATURDAY - A mix of sun and cloud / northwest winds 10-15 km/h / alpine high temperature near -10SUNDAY - Sunny with cloudy periods / west winds 10-20 km/h / alpine high temperature near -8

Avalanche Summary

On Thursday, there were preliminary reports of size 1-1.5 loose avalanches, and size 1 human triggered storm slab avalanches.On Tuesday there was one size 1 human triggered persistent slab avalanche reported on a north aspect at 1100 m. It failed on the late January persistent weak layer, 40 cm deep and was triggered remotely (from a distance).Generally speaking, reports from the past week are mainly of wind slabs reacting to ski cuts, with a trend toward smaller (size 1) releases. Small (size 1-1.5) loose dry avalanches have also been observed releasing naturally from steeper, sun exposed slopes in recent days.Reports of human triggered persistent slab avalanches on the January weak layers have been on the decline, suggesting these layers have evolved into a lower likelihood/high consequence avalanche problem.

Snowpack Summary

10-25 cm of new snow sits on wind slabs, surface hoar (feathery crystals), and facets (sugary snow) and a crust on sun exposed slopes. The buried wind slabs are also sitting on facets and they may continue to be reactive. There are a two prominent weak layers in the upper snowpack that were buried in mid and late January. These can be found approximately 40-80 cm deep. Both layers consist of surface hoar and may be associated with a crust on steep, south facing slopes. These weak layers have been most reactive at lower elevations, and especially below treeline.The lower snowpack is generally considered to be strong, except for shallow, rocky areas where the cold temperatures continue to facet (weaken) the snowpack.

Avalanche Problems

Storm Slabs

Fresh storm slabs may be reactive, especially in wind loaded areas.
Exercise increased caution around wind loaded pockets near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 1.5

Persistent Slabs

Two persistent weak layers are buried approximately 40 cm and 80 cm. These layers have evolved into a lower likelihood/high consequence avalanche problem.
Maintain diligent group management around open and/or sparsely treed slopes at treeline and below.Exercise increased caution around low elevation cut-blocks where this layer has been well preserved.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood: Unlikely

Expected Size: 1 - 2