Avalanche Forecast

Issued: Dec 24th, 2021 4:00PM

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

Avalanche Canada wlewis, Avalanche Canada

Variable winds will load unusual terrain features throughout the day. Avoid recently loaded slopes, and approach ridge crests carefully on all aspects. 

Summary

Confidence

High - We have a good understanding of the snowpack structure and confidence in the weather forecast

Weather Forecast

Arctic air pushes south into the interior, bringing frigid winter conditions that will see the Cariboos through Christmas.

FRIDAY NIGHT: Flurries with trace accumulations. Light east/northeast winds. Low of -22.

SATURDAY: Partly cloudy with light snowfall, up to 3cm over the day. Winds increase to moderate northeasterlies, gusting strong. Alpine high of -20. 

SUNDAY: Cloudy with isolated flurries. Moderate northeasterly winds, and alpine highs of -25. 

MONDAY: A mix of sun and cloud, with increasing westerly winds. No precipitation. Alpine high of -25.

Avalanche Summary

Few avalanches observations have been reported due to poor visibility and limited industry operators over the holiday season.

A natural avalanche cycle is expected to have occurred throughout the heavy snowfall received on Wednesday, at alpine and upper treeline elevations. The storm snow will take time to bond with the snowpack, and will continue to be reactive to human triggers. 

Nearby in the North Rockies several size storm slabs were observed on north and east facing slopes at treeline. Shooting cracks (a sure sign of instability) were observed on steep convex rolls.

If head into the mountains, please submit your findings and photos through a Mountain Information Network report.

Snowpack Summary

25-40cm of very light new snow has accumulated this week. Recent strong winds have created deeper deposits in wind loaded features at treeline and above. 

On the western side of the Cariboos, a thin crust sits 5cm deep in the snow snow. This will limit the extent of wind transport possible, but may also create reactivity as winds build slabs above this layer. 

The crust formed by the early December rain event sits 60-100cm deep and is found up to 1800m in the southern Cariboos. In most terrain the snow above is well bonded to the crust. In areas where the crust is buried deeper than one meter, it has begun to decompose and show limited reactivity. The most recent reactivity was located in treeline terrain west of Blue River. 

Terrain and Travel

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Loose avalanches may start small but they can grow and push you into dangerous terrain.

Problems

Wind Slabs

An icon showing Wind Slabs

Expect deeper deposits and reactivity as you move into wind effected terrain. Avoid ridge crests and cross loaded features. 

Previous southerly winds will have loaded north facing slopes, however as winds switch to the northeast expect loading on all aspects as reverse loading may occur. 

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1.5 - 2.5

Valid until: Dec 25th, 2021 4:00PM