Avalanche Forecast

Issued: Feb 2nd, 2019 8:04AM

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

percy woods, Parks Canada

Glacier.

A widespread natural avalanche cycle is expected to continue through to Saturday evening. Areas that have previously avalanched are reloading.

Summary

Weather Forecast

Light precipitation is forecast to continue through the day accompanied by moderate to strong South through West winds and an alpine high of -7C. Tonight cold air will invade with temperatures dropping into the -22C range accompanied by moderate Easterly winds and a trace of precipitation.

Snowpack Summary

At 1900m upwards of 75cm of storm snow has fallen in the past 48hrs with mod to strong S'ly winds. New snow sits atop hard wind slabs in the alpine and Jan 31 surface hoar at and below treeline. January 17 surface hoar is buried 70cm and is most reactive between 1400-1900m, and where it overlies a crust on steep solar aspects.

Avalanche Summary

A widespread avalanche cycle occurred yesterday and is expected to continue today with more snow and moderate to strong S through W winds. Avalanche control through the highway corridor produced numerous avalanches to size 3. Limited backcountry observations however Frequent Flyer was reported to have released to size 3 in the middle of the storm.

Confidence

Timing, track, or intensity of incoming weather system is uncertain

Problems

Storm Slabs

75cm of storm snow has created a reactive storm slab problem. Strong S winds are now battering the pass reloading areas that have previously avalanched. Rapid loading has turned these slabs into a touchy problem where natural avalanches are certain.

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.The new snow will require several days to settle and stabilize.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

Persistent Slabs

The Jan 17th Surface Hoar layer is now down 100cm+. This layer exists on all aspects, and is most problematic between 1400-1900m and on steep solar aspects where it overlies a crust.

Be aware of the potential for wide propagations.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Likely

Expected Size

2 - 3.5

Valid until: Feb 3rd, 2019 8:00AM