Avalanche Forecast

Archived

Nov 5th, 2020–Nov 6th, 2020

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

Glacier.

With the current weather and avalanche conditions, it is not a good day for skiing or riding @ Rogers Pass. Avalanche conditions will improve; however, travel will remain rugged when the rain soaked snow freezes!

Weather Forecast

A cold front is currently passing over Rogers Pass, Winds are extreme, Freezing levels are above ridge top (hoping they start to fall), and it is still raining!

Today: 4cm of new snow, winds gusting to over 100km/ph, and FL dropping to 1800m

Tonight: Fl dropping to Valley bottom, no precipitation, with a general clearing trend.

Snowpack Summary

Alpine: Height of snow is above average where the wind hasn't scoured it back to bare rock. Storm slabs continue to build

Treeline: The snowpack is shrinking with rain on snow conditions. Expect rain soaked snow, and isothermal conditions at this elevation.

Below Treeline: The height of snow varies from 30cm at HWY elevation, to 70cm.

Avalanche Summary

We are in the midst of a decent natural avalanche cycle, with winds reaching over 160km/h, above freezing temperatures to ridge top, and another 20mm of rain last night. We've observed a dozen new avalanches this morning in the Highway Corridor up to size 3, and are expecting the natural avalanche cycle to taper off as temps cool.

Confidence

Due to the quality of field observations

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.