Avalanche Forecast

Issued: Apr 7th, 2017 8:04AM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is considerable. Known problems include Storm Slabs, Persistent Slabs and Loose Wet.

Parks Canada danyelle magnan, Parks Canada

It's looking warm and wet again today. Warm temps overnight prevented an overnight recovery; as precipitation and winds pick up this afternoon hazard will rise. A cooling trend through the weekend should help to tighten up the snowpack.

Summary

Weather Forecast

Today expect flurries to accumulate to 10cm, with freezing levels hovering around 1800m and rain at low elevations. Winds should shift to S'ly and continue to load lees. Overnight we should see another 10cm snow with freezing levels lowering to 1200m. Saturday and Sunday should be a mix of sun and cloud, with a cooling trend and alpine highs of -6.

Snowpack Summary

Variable winds loaded lee's overnight. ~20cm of moist snow overlies a crust everywhere other than N aspects above 1800m. Below 1900m this slab has been saturated by rain. The upper snowpack is a complex mix of crusts. Deeper in the snowpack, old persistent weak layers that include crusts and facets have been reactive to large triggers like cornices

Avalanche Summary

High elevation N aspects hold dry snow that sluffs with skier traffic. At lower elevations, the wet snow is easily triggered running far and fast on crusts. Yesterday we observed a few size 2 natural storm slab avalanches with moist debris running to the end of the paths. Cornices or smaller avalanches have been triggering deep persistent layers.

Confidence

Timing of incoming weather systems is uncertain

Problems

Storm Slabs

An icon showing Storm Slabs
20cm of moist snow overlies a crust everywhere other than high elevation N'ly aspects. Winds have been shifting directions and will have formed deeper pockets on lee slopes. Rising freezing levels and continued loading will make them more reactive.
Watch for shooting cracks or stiffer feeling snow. Avoid areas that appear wind loaded.Choose well supported terrain without convexities.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Persistent Slabs

An icon showing Persistent Slabs
Cornices dropping and smaller avalanches have recently triggered deep, persistent weak layers. The resulting avalanches have been observed to run well into the valley bottoms. With continued loading during the storm likelihood will increase.
Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.Space out and travel quickly through runout zones of avalanche paths.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Loose Wet

An icon showing Loose Wet
At treeline and below, rain has saturated the snow that overlies a series of crusts. Warm overnight temps are keeping the snow weak. This wet snow will be easily triggered and will run far on the crust. Even if small, wet avalanches are powerful.
Ski short pitches and regroup in safe spots.Use safe ski cutting techniques before entering ski run.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Apr 8th, 2017 8:00AM