Archived

Avalanche Forecast

Apr 28th, 2017–Apr 29th, 2017

Alpine

Below Threshold

The avalanche danger rating in the alpine will be below threshold

Treeline

Below Threshold

The avalanche danger rating at treeline will be below threshold

Below Treeline

Below Threshold

The avalanche danger rating below treeline will be below threshold

Alpine

Below Threshold

The avalanche danger rating in the alpine will be below threshold

Treeline

Below Threshold

The avalanche danger rating at treeline will be below threshold

Below Treeline

Below Threshold

The avalanche danger rating below treeline will be below threshold

Alpine

Below Threshold

The avalanche danger rating in the alpine will be below threshold

Treeline

Below Threshold

The avalanche danger rating at treeline will be below threshold

Below Treeline

Below Threshold

The avalanche danger rating below treeline will be below threshold

Regions: Glacier.

Get an early start to your day to take advantage of the frozen snowpack in the morning. It rapidly breaks down and becomes unstable with daytime warming, sunshine, or rain.

Weather Forecast

Cloudy with sunny periods today, with clearing tonight and freezing levels dropping to valley-bottom. Flurries are expected on Saturday, bringing up to 10cm to the alpine elevations, and freezing levels may rise to 1800m. Flurries will continue on Sunday, with 5cm in the alpine, freezing levels around 1600m, and winds moderate from the west.

Snowpack Summary

High elevation N aspects still hold a winter snowpack with surface windslab that may be sensitive to human triggering given the right location. On solar aspects expect temp crusts and sun crusts in morning and moist surface as the day warms. Field trip yesterday showed no recovery in surface crusts due to rain overnight.

Avalanche Summary

A size 3.5 natural glide crack avalanche adjacent to the highway released during Thursday morning. No other new activity has been observed.

Confidence

Avalanche Problems

Wind Slabs

Expect to find pockets of windslab on high elevation N aspects formed by recent S-SW winds. Skiers reported triggering windslab to size 2 on Sunday.

Watch for whumpfing, hollow sounds, and shooting cracks.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 3

Loose Wet

Poor overnight crust recovery at low elevations last night. Surface crust breakdown can be expected with daytime warming. Wet slides may occur later in the day.

Use extra caution on solar slopes or if the snow is moist or wet.Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

Cornices

Cornices are huge and hanging over alpine lee slopes in many places. Daytime warming may promote failure of these large triggers. Cornice failure may wake persistent weak layers.

Pay attention to overhead hazards like cornices which could trigger the deep persistent slab.Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 3