Avalanche Forecast

Issued: Dec 8th, 2015 8:00AM

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

chris gooliaff, Parks Canada

Glacier.

Today's warm storm will overload the Dec 2 weak layer. An avalanche cycle is highly likely. The ski hill will be a better place to head today.

Summary

Weather Forecast

The warm, wet storm has arrived and it is bringing upwards of 35cm of snow. Freezing levels will rise, spiking mid-day between 1500-2000m. Strong W winds will accompany the storm. A smaller pulse is expected for Wednesday, to add one more punch to the snowpack.

Snowpack Summary

The widespread Dec 2 surface hoar layer is down 30-65cm and is reactive to human loading. Early November surface hoar layers were also reactive in snowpack tests yesterday, popping off with heavy loads. These test results suggest with a heavy enough load, avalanches could step-down and become much larger.

Avalanche Summary

A natural cycle is underway, with numerous size 2 to size 3 avalanches observed along the highway corridor last night and this morning. Yesterday, field teams were able to easily ski-cut size 1 soft slabs from unsupported features, especially below 1700m

Confidence

Problems

Storm Slabs

The Dec 2nd surface hoar layer has reached critical load. Expect the storm slab to be reactive to both human and natural triggering.

Minimize overhead exposure during periods of heavy loading from new snow, wind.Watch for whumpfing, hollow sounds, and shooting cracks.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

Wind Slabs

Strong S winds formed wind slabs on N aspects in the alpine and tree-line. In some locations these slabs will be resting on the Dec 2nd surface hoar layer and will be sensitive to human triggering.

Minimize overhead exposure during periods of heavy loading from new snow, wind.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Dec 9th, 2015 8:00AM