Avalanche Forecast

Issued: Nov 22nd, 2017 4:16PM

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

rupert wedgwood, Parks Canada

Jasper.

Stay out of avalanche terrain as its dangerous times,

Summary

Weather Forecast

The Pineapple Express is tracking over the region bring warm wet conditions until Thursday PM. Tonight 22cm new snow in the alp with another 9cm on Thur. Expect rain at lower elevations. Freezing levels will remain at treeline until late Thursday. Ridge wind west: 30 km/h gusting to 75 km/h.

Snowpack Summary

A persistent slab of between 40cm - 200cm sits over the Halloween Crust. This crust can be found up to 2,700m in the Icefields and depending on its location is between 20cm - 40cm above the ground. Moist or wet snow, from rain during the past 24hrs, extends to 2,200m. Thinner wind slabs in the higher alpine can be expected on lee features

Avalanche Summary

Numerous persistent slab avalanches to size 2.5 observed from field teams today. These are failing at treeline and upper elevations as a result of warm temperatures, rain and additional snow loading. At treeline and below point release moist or wet snow avalanches are occurring. A field team remote triggered a size 2 persistent slab from 60m.

Confidence

Problems

Persistent Slabs

An avalanche cycle is ongoing. Remote triggering at treeline has occurred in the Hilda Creek area which speaks to the sensitivity. Debris is running into the valley bottom where snow depths are much thinner and this problem layer may not exist.

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 3

Loose Wet

The distribution of this problem will be tied to the freezing levels. Rain is expected to continue near and below treeline tonight and tomorrow morning.

Avoid terrain traps, such as gullies, where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Valid until: Nov 23rd, 2017 4:00PM