Avalanche Forecast

Issued: Jan 23rd, 2018 4:00PM

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

Lisa Paulson, Parks Canada

Little Yoho.

The snow and wind in the forecast may enough to overload one of the several weak layers in some locations, minimize your exposure to overhead hazard. Great skiing can be found in conservative terrain.

Summary

Weather Forecast

We are in the influence of a SW flow with a series of storms moving in off the coast. Expect light snow ~ 5-10 cm per day for the next three days. Temps will be cool in the -5 to -15 range with Wednesday being the warmest and winds generally light to moderate from the SW.

Snowpack Summary

Recent winds have developed windslabs on alpine lee slopes. In sheltered areas, 25- 40 cm of snow overlies the Jan 16 layer (the first of 3 weak layers). The Jan 6 is below this and is 40 -60 cm down and the Dec. 15 is deeper yet at 60-80 cm down. Each of these layers are a mix of surface hoar, facets and sun crust depending on aspect and elevation

Avalanche Summary

No new avalanche activity reported in this forecast region.

Confidence

Problems

Wind Slabs

Recent snow and wind are have created new windslabs on lee slopes in the alpine.

Use caution in lee areas. Recent wind loading has created wind slabs.If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: North, North East, East, South East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

There are 3 weak layers in the upper snowpack: Jan. 16, Jan 6 and Dec. 15. They are a mix of sun crust, facets and surface hoar depending on aspect and elevation. Avalanches initiated in any of these layers will likely step down to the Dec. 15 layer

Avoid open slopes and convex rolls at treeline where buried surface hoar may be preserved.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Jan 24th, 2018 4:00PM