Avalanche Forecast Cariboos

Date Issued: Valid Until:

Avalanche Canada kdevine, Avalanche Canada

Avalanche Forecast

Sun Feb. 3rd ยท 4:09PM

Alpine

Danger Ratings Considerable

Treeline

Danger Ratings Considerable

Below Treeline

Danger Ratings Considerable
Wind Slabs Wind Slabs
Persistent Slabs Persistent Slabs

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Considerable

Below Treeline

Danger Ratings Considerable

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Considerable

Below Treeline

Danger Ratings Considerable
Human triggered avalanches remain likely, especially in wind loaded areas and at lower elevations where a buried surface hoar layer has produced avalanches recently.

Confidence

Moderate -

Weather Forecast

SUNDAY NIGHT - Mainly cloudy with isolated flurries / light northeast winds / alpine low temperature near -25MONDAY - Sunny with cloudy periods / northeast winds 10-30 km/h / alpine high temperature near -16TUESDAY - Mainly sunny / northeast winds 15-25 km/h / alpine high temperature near -13WEDNESDAY - A mix of sun and cloud / northwest winds, 15-35 km/h / alpine high temperature near -11

Avalanche Summary

Widespread avalanche activity was reported on Saturday. Natural avalanches to size 3 and human triggered avalanches to size 2 were reported. Many of these failed on a persistent weak layer that was buried in mid January. This layer was the most reactive at treeline and below.There is a great MIN report here detailing the reactivity of the mid January layer in Allen creek on Saturday.Field observations were limited on Friday, but it is likely that a natural avalanche cycle was occurring throughout the day. There were reports of a few human triggered avalanches to size 2 occurring at treeline and below on Friday. Some of these were remote triggered (triggered from a distance), and failed on a persistent weak layer of surface hoar that was buried in mid January.There are two great MIN reports that outline how reactive the mid January persistent weak layer was on Friday. They can be found here and here.

Snowpack Summary

30-50 cm of snow has fallen in the Cariboos since Thursday. This new snow is sitting on surface hoar (feathery crystals), facets (sugary snow) and a crust on sun-exposed slopes. Recent strong winds have redistributed the new snow and formed wind slabs at all elevations.40-80 cm of snow now sits on a persistent weak layer that was buried in mid January. This layer consists of surface hoar and a crust on sun-exposed slopes. It is most prominent at treeline and below, and was very reactive during the recent storm. It remains to be seen how this layer will behave as temperatures drop. It may still be reactive to human triggers.

Problems

Wind Slabs

Wind Slabs

30-50 cm of snow has fallen since Thursday. In many areas, recent winds have formed wind slabs at all elevations and on all aspects due to a shift in wind direction.

If triggered, wind slabs may step down to deeper layers and result in even larger avalanches.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Possible

Expected Size

1 - 2
Persistent Slabs

Persistent Slabs

40-80 cm of snow sits above a weak layer of surface hoar and crust that was buried in mid January. This layer was reactive during the storm, and may still be reactive to human triggers.

Any steep opening in the trees should be treated as suspect right now.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Likely - Possible

Expected Size

1.5 - 3