Avalanche Forecast

Archived

Feb 9th, 2015–Feb 10th, 2015

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

Little Yoho.

Avalanche control will take place on Mt. Dennis, Mt Field, and Mt. Hector on Tuesday. Please no skiing or climbing in these areas.

Weather Forecast

Isolated flurries with freezing levels rising to 1800m on Tuesday. Little in the way of precipitation through the end of the week.

Snowpack Summary

60-90 cm of recent storm overlies a crust from January 30th. The recent heavy precipitation, wind and warmer temperatures have created storm slabs which will put an enormous amount of stress on the January 30th crust interface. Isothermal conditions exist at treeline and below.

Avalanche Summary

Avalanche control over the past three days have produced numerous slab avalanches up to size 3. Many of the avalanches started dry and turned wet at lower elevations. Also there was evidence of a widespread cycle up to size 3.5 throughout the forecast region. Some avalanches running close to full path.

Confidence

Freezing levels are uncertain

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.