Avalanche Forecast

Issued: Dec 9th, 2014 7:42AM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

A warm, wet and windy impulse of weather will lead to an increase in danger levels. Avoid all avalanche terrain during times of rain and/or rapid loading by wind and snow.

Summary

Confidence

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

Weather Forecast

Warm, wet and windy for the next couple of days. Freezing levels are expected near 2200m for both Wednesday and Thursday with winds reaching up to 125km/h from the SW. Precipitation is expected to be light, but will fall as rain at mid to lower elevations.

Avalanche Summary

Isolated snowballing and very small loose wet avalanches were observed today at lower elevations.

Snowpack Summary

Light rain fell through the day to an elevation of at least 2300m. The extent of the rain soaked snow is unknown at this time. Blowing snow was observed at ridge top due to extreme SW winds. Settlement of the upper and mid snowpack has caused an increase in the potential for human-triggering due to more dense slab properties above the weak basal layers. The November rain crust is the main culprit here and will remain a serious concern for sometime to come.

Problems

Loose Wet

Rain at lower elevations is making the snowpack very weak and ripe for loose wet slides.

Watch for clues, like sluffing off of cliffs, that the snowpack is warming up. >

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Likely

Expected Size

1 - 2

Deep Persistent Slabs

Slabs are sitting on a weak basal combination of facets overtop of the November rain crust. Wide propagations and more sensitive triggering are now possible due to the recent increase in slab density.

Be aware of the potential for full depth avalanches due to deeply buried weak layers.>Avoid convexities or areas with a thin or variable snowpack.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 4

Wind Slabs

Wind slabs remain dominant in Alpine terrain. These slabs could step down to the November rain crust.

Use caution in lee areas in the alpine. Recent wind loading have created wind slabs.>Avoid cross loaded features.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Valid until: Dec 10th, 2014 2:00PM