Avalanche Forecast

Issued: Apr 2nd, 2017 3:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs, Cornices and Loose Wet.

rbuhler, Avalanche Canada

South Coast Inland.

Watch for lingering wind slabs in high north facing terrain. Extra caution is needed around all steep sun exposed slopes as well any slopes exposed to large cornices.

Summary

Confidence

Moderate - Timing or intensity of solar radiation is uncertain

Weather Forecast

Mostly sunny conditions are expected on Monday with light to moderate alpine wind from the north. Freezing levels are forecast to drop to around 500 m Sunday overnight and reach around 1500 m on Monday afternoon. Increasing cloud cover is expected on Tuesday with light to moderate alpine wind from the south and freezing levels reaching around 1700 m in the afternoon. Light precipitation is forecast for Wednesday with strong alpine wind from the southwest and freezing levels reaching around 2000 m in the afternoon.

Avalanche Summary

On Saturday, skiers triggered a few size 1 wind slabs in leeward features in the alpine and at treeline in the north of the region. A few natural cornice releases up to size 2.5 were also observed in the north of the region but did not trigger slabs on the slopes below. No new avalanches were reported on Friday. On Monday, wind slabs on northerly aspects in the alpine may still be reactive to human triggering. Natural solar triggered sluffing is expected from steep sun exposed slopes and natural cornice releases are also possible when the sun is shining.

Snowpack Summary

A widespread crust is expected to have formed on all aspects and elevations except for high north facing slopes. Recent strong winds from the south have formed wind slabs in the alpine and have added load to cornices. On sun exposed slopes and at lower elevations, several crusts likely exist in the upper snowpack. In the north of the region, the February persistent weak layers may still be found in the alpine and are down 100-140cm. They include a buried surface hoar layer as well as a crust/facet layer. In the southern parts of the region, the mid and lower snowpack are generally well settled and strong.

Problems

Wind Slabs

Wind slabs have recently formed in north facing terrain in the alpine and are expected to remain reactive to human triggering on Monday.

Use ridges or ribs to avoid pockets of wind loaded snow.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Cornices

Large cornices are expected to become weak with daytime warming or sustained sun exposure. A cornice falling still has the potential to trigger isolated large slab avalanches on the slope below.

Pay attention to overhead hazards like cornices which could potentially trigger deeper weak layersCornices become weak with daytime heating or solar exposure

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Loose Wet

Solar triggered loose wet avalanches should be expected from steep sun exposed slopes during the heat of the day.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.Be cautious of sluffing in steep terrain.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Apr 3rd, 2017 2:00PM