Avalanche Forecast

Issued: Jan 10th, 2017 3:43PM

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

Avalanche Canada rbuhler, Avalanche Canada

Watch for areas that have recently been affected by the wind. Wind slabs are expected to be lingering in leeward terrain features.

Summary

Confidence

Moderate - Wind speed and direction is uncertain

Weather Forecast

Sunny conditions are expected on Wednesday with treeline temperatures around -15C and light northerly wind in the alpine. Sunny conditions continue for Thursday and Friday with treeline temperatures remaining around -15C during the afternoon and light to moderate alpine wind from the northwest.

Avalanche Summary

On Tuesday, explosives triggered one size 1.5 storm slab on a northeast aspects at 2100 m elevation which was 15-20 cm thick. On Monday, several natural storm slab avalanches up to size 2 were observed on a variety of aspects. Ski cutting also produced several storm slab avalanches up to size 1.5. These slabs were typically 15-20 cm thick and were reported to be very reactive in gulley features.On Wednesday, recently formed wind slabs may still be reactive to human triggering. With the winds recently switching directions, wind slabs should be expected on a variety of aspects.

Snowpack Summary

15-20 cm of new snow has buried a variable snow surface which consists of wind scoured surfaces or old wind slabs in exposed terrain, surface hoar up to 20 mm in sheltered terrain, and/or widespread faceted old snow. Recent moderate winds from a variety of directions is expected to have redistributed some of this new snow in wind exposed terrain. Deeper in the snowpack, the mid-December persistent weak facet layer has been more prominent and reactive in the Corbin area than areas closer to Fernie. The layer is generally considered dormant right now but may wake up during the next storm or period of warming.

Problems

Wind Slabs

An icon showing Wind Slabs
Recently formed wind slabs may still be reactive to human triggering in immediate leeward features in wind exposed terrain. Wind direction has changed recently and wind slabs may exist on all aspects.
Wind direction has changed recently. Watch for slabs on all aspects.Use ridges or ribs to avoid pockets of wind loaded snow.Avoid areas where the surface snow feels stiff or slabby.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 11th, 2017 2:00PM