Avalanche Forecast

Issued: Dec 14th, 2018 4:57PM

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

jonas hoke, Parks Canada

Jasper.

A significant natural avalanche cycle has just begun to taper off, avoidance of avalanche terrain that hasn't had previous activity is recommended.

Summary

Weather Forecast

A fast moving cold front sweeps across BC into Alberta Friday night (up to 15cm of snow is forecast). This will be followed by a ridge of high pressure giving clearing skies and a cooling trend for the weekend.Click here A detailed mountain weather forecast is available from Avalanche Canada.

Snowpack Summary

Up to 60cm of new snow has fallen since Dec. 11th in the Parkers ridge ridge area (much less to the north), and has been redistributed by moderate to strong S-SW wind. The resulting storm and wind slabs overly several weak interfaces - facets, crusts and isolated surface hoar. Deep persistent weaknesses from early in the season remain a concern.

Avalanche Summary

A natural avalanche cycle triggered by this weeks storm resulted in numerous storm and wind slab avalanches up to size 3.5. Avalanche control work in the Parkers ridge area on Friday (Dec. 14th) produced numerous slab avalanches up to size 2.5 - direct evidence that despite natural triggering having slowed, human triggering remains likely.

Confidence

Problems

Storm Slabs

The new snow will require several days to settle and stabilize.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Wind Slabs

Use caution in lee areas. Recent wind loading has created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1.5 - 3

Deep Persistent Slabs

Be aware of the potential for wide propagations.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3.5

Valid until: Dec 15th, 2018 4:00PM