Avalanche Forecast

Issued: Nov 15th, 2015 3:00PM

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

mike.koppang, Alberta Parks

Kananaskis.

The winds today were a big issue and have built some touchy windslabs at ridgetop. Any windloaded terrain feature should be treated with great suspicion. We now likely have hard slabs sitting on top of a structurally weak base layer. (PJ)

Summary

Confidence

Fair - Timing of incoming weather systems is uncertain on Tuesday

Weather Forecast

The forecast indicates falling freezing levels to valley bottom for Monday. Winds will diminish to the light/moderate range from the NW and with some possible light flurries.

Avalanche Summary

A medium sized avalanche cycle was observed today in the Kananaskis and Highwood areas today. Strong to extreme winds were seen moving the recent storm snow stripped off of windward south and west facing slopes onto north and east aspects as windslabs. These slabs are overloading the unconsolidated lower pack including facets from November 5th. In one case today, an avalanche up to size 2.5 failed on these facets on the ground and ran full path to the creek

Snowpack Summary

High freezing levels (2300 meters) and warm temperatures are promoting very rapid settlement of the new storm snow into a more cohesive slab at all elevations and aspects The winds were the main culprit today with serious redistribution of the new snow into windslabs on lee features. We found evidence of buried windslabs in exposed features at treeline and the lower structure of the snowpack was typically soft, weak and facetted.

Problems

Wind Slabs

Avoid lee and cross-loaded terrain near ridge crests.>Be careful with wind loaded pockets while approaching and climbing ice routes.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 4

Storm Slabs

Avoid areas with overhead hazard.>Avoid shallow snowpack areas where triggering is more likely.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Nov 16th, 2015 2:00PM