Avalanche Forecast

Issued: Apr 3rd, 2018 4:46PM

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

Avalanche Canada simonhorton, Avalanche Canada

Watch for areas where the surface snow feels stiff or slabby, especially in open wind-affected terrain.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain on Thursday

Weather Forecast

WEDNESDAY: Cloudy with scattered flurries, moderate west wind, freezing level up to 1400 m with alpine high temperatures near -4 C.THURSDAY: Light flurries with 10-15 cm of low density snow, moderate west wind, freezing level up to 1000 m with alpine high temperatures near -7 C.FRIDAY: Morning flurries then clearing in the afternoon, moderate west wind, freezing level up to 1500 m with alpine high temperatures near -2 C.

Avalanche Summary

Numerous small avalanches were reported in the top 10-20 cm of snow on Monday and Tuesday. They included size 1 slab avalanches in wind-affected terrain and loose dry avalanches in steep sheltered terrain. A few size 2 wind slabs were observed in alpine terrain after Sunday night's storm.On Sunday, a size 2 wind slab avalanche was triggered with explosives on a north aspect at 2100 m. On Saturday, a large storm slab avalanche (size 2.5) was triggered on a treeline feature. See this MIN post for a photo and more details.

Snowpack Summary

Roughly 15 cm of snow sits above a variety of crusts on all but high north aspects. Wind has formed isolated slabs in lee features, and in some cases snow may be poorly bonded to the crusts.There are some reports of a surface hoar layer roughly 80 cm deep on north aspects at treeline, but no recent avalanche activity on this layer. A layer of sugary facets around a crust exists near the bottom of the snowpack, but this layer has been inactive for some time.Cornices are large along ridgetops and were actively failing last week.

Problems

Wind Slabs

An icon showing Wind Slabs
Shifting winds have formed slabs on lee features on a variety of aspects.
Pay attention to overhead hazards like cornices which could easily trigger slabs.Use ridges or ribs to avoid pockets of wind loaded snow.Caution around convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 4th, 2018 2:00PM