Avalanche Forecast

Issued: Mar 27th, 2021 4:00PM

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

Avalanche Canada kdevine, Avalanche Canada

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Fresh snow is expected to accumulate during the day, with strong southwest wind. The timing of the storm's arrival is uncertain, so watch for changing conditions and look for clues of instability such as whumpfing, cracking, or recent avalanches. 

Summary

Confidence

Moderate - Uncertainty is due to the timing of the incoming weather system.

Weather Forecast

SATURDAY NIGHT - Mainly cloudy with a few flurries / strong southwest wind / alpine low temperature near -2 / freezing level 1700 m

SUNDAY - Snow, 10-20 cm, with another 15-20 cm overnight / strong southwest wind / alpine high temperature near -1 / freezing level 1800 m

MONDAY - Mainly cloudy with scattered flurries / moderate west wind / alpine high temperature near -7 

TUESDAY - A mix of sun and cloud / light to moderate west wind / alpine high temperature near -5 / freezing level 1500 m

Avalanche Summary

Fresh storm slabs are expected to build and become increasingly reactive throughout the day on Sunday. Wet loose avalanches are possible at lower elevations where rain is expected.

On Friday, there were a few reports of size 1 human triggered storm slab avalanches on north aspects in the alpine.

On Thursday there were a few reports of natural size 1.5-2 storm slab avalanches, as well as a size 1.5 explosive-triggered cornice.

A large (size 2) glide slab occurred overnight last Friday on a lower elevation slope on Mt. Fernie. It may have been coaxed into action by overnight rainfall. This serves as a great reminder to avoid slopes with glide cracks on them at all times. They are inherently unstable and can release at any time.

Snowpack Summary

10-20 cm of snow is expected to accumulate during the day on Sunday with strong southwest wind. The precipitation may fall as rain below treeline.

Fresh storm slabs are expected to build throughout the day. This new snow will fall on a variety of old surfaces, such as a crust below about 1700 m and on solar aspects, and onto wind affected snow at upper elevations.

 The mid and lower snowpack is generally well settled and strong.

Terrain and Travel

  • Storm slab size and sensitivity to triggering will likely increase through the day.
  • Avoid steep slopes when air temperatures are warm, it is raining, or solar radiation is strong.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Storm Slabs

An icon showing Storm Slabs

Fresh storm slabs are expected to become increasingly reactive throughout the day, especially in wind loaded terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Loose Wet

An icon showing Loose Wet

Wet loose avalanches are possible at lower elevations where rain is expected.

Aspects: All aspects.

Elevations: Below Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Mar 28th, 2021 4:00PM