Avalanche Forecast

Issued: Nov 27th, 2011 4:00PM

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

max darrah, Parks Canada

Jasper.

Recent snowfall has increased the avalanche danger and will take time to stabilize - avoid avalanche terrain until the cooler temps arrive and strengthen the snowpack.

Summary

Weather Forecast

Snowpack Summary

Avalanche Summary

Confidence

Timing of incoming weather systems is uncertain on Monday

Problems

Storm Slabs

15-20cm of new snow fell on Sunday along with moderate to strong SW winds. Steady rain fell below 1400m. Widespread storm slabs will be very touchy until the arrival of colder temps later in the week.

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 3

Wind Slabs

Gusty and variable winds have formed wind slabs on all aspects at upper elevations, especially in exposed areas. These slabs will be more sensitive to triggering with the latest storm snow.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 4

Deep Persistent Slabs

Early season wind slabs that sit above weak basal facets have received significant load with the recent wet and heavy snow. This new load has the potential to cause full depth releases and wide propagations.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

3 - 4

Valid until: Nov 28th, 2011 4:00PM