Avalanche Forecast

Archived

Apr 17th, 2016–Apr 18th, 2016

Alpine

Below Threshold.

Treeline

Below Threshold.

Below Treeline

Below Threshold.

Alpine

Below Threshold.

Treeline

Below Threshold.

Below Treeline

Below Threshold.

Alpine

Below Threshold.

Treeline

Below Threshold.

Below Treeline

Below Threshold.

Regions

Little Yoho.

A warm and sunny day Sunday with temperatures expected to climb through the night producing NO FREEZE Monday morning. Poor travel and likely an avalanche cycle can be expected as freezing levels reach 3800m Monday and stay there through Tuesday.

Weather Forecast

A weak freeze occurred Sunday morning with calm winds and clear skies allowing strong solar effect combined with freezing levels that are expected to rise steadily into Sunday night. With NO FREEZE forecast Monday or Tuesday expect the heating effects to compound each day as freezing levels reach 3800m.

Snowpack Summary

We are into a spring cycle for most of the Little Yoho area except in high north facing alpine. Occasional pockets of deep instability may still be encountered and triggered from shallow locations during warm periods of the day. 5cm of recent snow sits on crusts found everywhere but above 2600m on North aspects became moist today with solar heating

Avalanche Summary

Loose wet activity to sz 2 on steep solar slopes with the surface snow failing over the melt-freeze crusts has been seen over the last two days with patchy skies. At the time of writing today (14:00) not much new has been seen however crusts are certainly breaking down and activity is expected.

Confidence

Problems

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.

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.