Avalanche Forecast

Issued: Jan 22nd, 2017 3:57PM

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

shorton, Avalanche Canada

South Rockies.

The consequence of triggering a deep persistent slab avalanche warrants a cautious approach to steep open terrain.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

MONDAY: Isolated flurries with up to 5 cm by the morning, light north winds, alpine temperatures around -8 C.TUESDAY: Cloudy with sunny periods, light northwest winds, alpine temperatures around -10 C.WEDNESDAY: Mix of sun and cloud, light northwest winds, alpine temperatures around -10 C.

Avalanche Summary

No new avalanches were reported on the weekend. Wind slabs are possible to trigger in isolated locations, but the main concern continues to be the possibility of triggering the weak faceted layers deeper in the snowpack.

Snowpack Summary

A dusting of new snow sits above hard wind-affected surfaces, while a recent melt-freeze cycle has left a hard crust at lower elevations (up to 1400 m in the west and 1900 m in the east). The snowpack is quite variable throughout the region. In deeper snowpack areas, the snowpack appears to be well settled with isolated concerns about the mid-December facet layer buried 50-100 cm deep. In shallow snowpack areas and lower elevations, the snowpack is weak and faceted. In these areas, winds have formed isolated hard slabs above weak facets with the potential for large persistent slab avalanches.

Problems

Deep Persistent Slabs

Triggering deeper weak layers remains possible where hard slabs sit above weak sugary snow.

Be aware of the potential for full depth avalanches due to deeply buried weak layers.Danger exists where denser snow overlies weak, sugary snow below.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Wind Slabs

Watch for wind slabs on lee and cross-loaded features at higher elevations.

Be cautious as you transition into wind affected terrain.Use ridges or ribs to avoid pockets of wind loaded snow.Avoid areas where the surface snow feels stiff or slabby.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 23rd, 2017 2:00PM