Avalanche Forecast

Issued: Jan 18th, 2017 4:00PM

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

jonas hoke, Parks Canada

Waterton Lakes.

While deep persistent layers may be stubborn to initiate, the consequences of finding the sweet spot would be substantial. It might not yet be time to ski big open terrain.

Summary

Weather Forecast

The ongoing effects of a strong south west flow will continue to give strong SW winds, scattered precipitation and warm temps through Thursday. On Friday the flow begins to shift to more of a weak Westerly, giving clearing skies, tapering winds and cooling temps in to the weekend.

Snowpack Summary

Warm temps have moistened the upper snowpack below treeline. Strong to Extreme SW winds have created hard Wind Slabs and/or sastrugi in all open areas. Faceted layers in the mid and lower snowpack remain a concern, particularly in shallow snowpack areas where facetting is more pronounced and triggering is more likely.

Avalanche Summary

No recent avalanche activity has been observed. A Large (Size 3) Deep Persistent slab avalanche was observed in Alpine terrain last Friday, at 2250m on a North aspect. Triggered by a small Wind Slab hitting a shallow spot, this propagated across the slope into the adjacent deeper snowpack and was up to 2m thick in places.

Confidence

Due to the number of field observations

Problems

Deep Persistent Slabs

Use caution on open slopes and convex rolls Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3

Loose Wet

Use caution above cliffs where small avalanches may have severe consequences.Use extra caution on slopes if the snow is moist or wet.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 1

Valid until: Jan 21st, 2017 4:00PM