Avalanche Forecast

Issued: Dec 21st, 2017 3:23PM

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

Avalanche Canada jfloyer, Avalanche Canada

Watch for wind slabs forming on the downwind side of ridges and terrain breaks in exposed areas.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

Friday: Dry and sunny. Winds moderate from the northeast. Treeline temperatures around -20C.Saturday: Dry and sunny. Winds moderate from the east. Treeline temperatures around -22C.Sunday: Dry with some sun and cloud. Winds moderate from the southeast. Treeline temperatures around -23C.

Avalanche Summary

No recent avalanches observed. If you're out in the mountains and see recent avalanches please snap a photo and submit your information to the Mountain Information Network.

Snowpack Summary

Relatively light recent snow amounts have been accompanied by westerly and northwesterly winds. 20-ish cm below the surface, a highly variable weak layer exists. It comprises of facets in cold areas, crusts on solar aspects, and in protected areas below 1500m, feathery surface hoar. In most places, insufficient snow has fallen above this layer for it to be reactive, but it should be considered in deep snow areas, or where the wind has blown additional snow over the top of it.Two crusts, which formed near the end of November, are found approximately 30 to 50cm below the surface. These crusts are widespread and extend into the alpine. Previous snowpack tests produced hard results on these crusts, but we have not seen any recent information about their sensitivity to triggering. Below these crusts, a well settled mid-pack overlies the late October crust which is down near the ground. The October crust is widespread and has not been reactive to human triggering since the end of November. Average snowpack depths in the region are between 80 and 140cm at treeline.

Problems

Wind Slabs

An icon showing Wind Slabs
Wind slabs are most likely to be found immediately lee of ridge crest in exposed terrain. While relatively small, they could be problematic in complex terrain.
Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Use ridges or ribs to avoid pockets of wind loaded snow.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Dec 22nd, 2017 2:00PM