Avalanche Forecast

Issued: Nov 27th, 2014 3:00PM

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

Alberta Parks matt.mueller, Alberta Parks

Unpredictable. That is the best word to describe the snowpack right now. Patience and conservative terrain choices are very important while we wait to see how the snow adjusts to the new load.

Summary

Confidence

Good

Weather Forecast

Today's weather matched the forecast almost exactly. Temps were warm (0 @ 2300m), winds were strong and the snowfall was moderate. The next 48 hours are expected to bring even more snow (up to 58cm's) in three distinct pulses. Tomorrow's pulse will be more sustained in terms of snowfall. As the storm fades overnight friday, the current westerly flow will turn into a northerly. As expected, the snow and wind will stop, and the temperatures will fall to -27.

Avalanche Summary

Skies were partially obscured today so there were no avalanches directly observed. However there was one audible avalanche during our weather observations. Whumphing and cracking was also noted in various locations.

Snowpack Summary

We received an average of 12cm's in the last 24hrs with more on the way. In the alpine, storm snow has had widespread wind effect and redistribution. Alpine storm slabs are widespread, and building fast. At treeline elevations the wind is less powerful, but still a major factor in storm slab development. The relatively warm incoming snow at treeline is prime for windslab development. The Nov 6th crust is now down 40-50cm's and likely to become reactive as the weight of the new snow stresses it. The general feeling with the snowpack is that it's  in a time of change and can't be trusted just yet. Snow depths are: Burstall Pass 83, Highwood 53,  Aster Lake 87

Problems

Storm Slabs

An icon showing Storm Slabs
The warm incoming snow will form slabs of various types. We can expect to see wind slabs (redistribution), wind pressing and even settlement slabs in alpine or wind exposed areas. Watch for "cakey" snow texture and choose small, supported terrain.
Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>Avoid areas with overhead hazard.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Wind Slabs

An icon showing Wind Slabs
The storm slabs will likely step down to this layer. The poor bond with the Nov 6th crust is the concern.
Dig down to find and test weak layers before committing to a line.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Loose Dry

An icon showing Loose Dry
Very steep terrain will produce small loose dry slides. Be aware that these may be a trigger for something much bigger.
Be cautious of sluffing in steep terrain.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Nov 28th, 2014 2:00PM