Avalanche Forecast Sea to Sky

Date Issued: Valid Until:

Avalanche Canada dsaly, Avalanche Canada

Avalanche Forecast

Tue Feb. 12th ยท 4:36PM

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Moderate
Storm Slabs Storm Slabs

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Moderate

Alpine

Danger Ratings Considerable

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Moderate
New snow and wind will hide older, recently formed wind slabs and build new slabs over old ones. The largest accumulations of snow, and potentially the most reactive, will be found in wind-loaded terrain.

Confidence

Moderate - Forecast snowfall amounts are uncertain

Weather Forecast

TUESDAY NIGHT: Mostly cloudy with isolated flurries, trace to 10 cm accumulation. Alpine temperature near -12C. Ridgetop winds moderate from the east.WEDNESDAY: Mix of sun and cloud. Alpine temperatures near -10C. Ridgetop winds light from the south-southeast.THURSDAY: Sunny with cloudy periods with flurries starting later in the day, up to 10 cm accumulation. Alpine temperature near -8C, freezing level rising to 600 m. Ridgetop winds moderate from the east-southeast.FRIDAY: Cloudy with flurries, trace to 5 cm. Alpine temperatures near -8. Ridgetop winds light from the south-southwest.

Avalanche Summary

Soft slab development in steep, lee terrain and loose, dry snow sloughing is being reported with the recent new snow.Over the weekend, small pockets of wind slab were reactive to skier traffic in steep and immediate lee features. Of note is a MIN from the Whistler backcounty reporting wind slabs at lower elevations and in more sheltered terrain than usual (see the MIN here).

Snowpack Summary

15-30 cm new snow fell on variable wind-pressed, wind-sculpted, exposed crust and windslab surfaces covering alpine and higher treeline elevations as a result of the recent extreme wind event. Additionally, the extreme winds deposited snow lower in start zones than usual and developed wind slabs in more protected areas and at lower elevations.Due to scouring and wind-loading, anywhere from 0-100 cm of new snow and old, wind-affected snow sits on a crust on all aspects below 2000m and solar aspects into the alpine. Above 1800 m, recent cold temperatures have been working to facet and break down the buried crust. In isolated and sheltered terrain at treeline and below, a layer of weak feathery surface hoar or sugary facets may be identified, but with little reactivity. The remainder of the snowpack is generally well-settled.

Problems

Storm Slabs

Storm Slabs

20-30 cm new snow is being redistributed by light to moderate winds. Deeper and more reactive depositions will be in wind loaded terrain.

The recent snow may now be hiding windslabs that were easily visible before the snow fell.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2