Avalanche Forecast

Issued: Mar 18th, 2021 4:00PM

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

Avalanche Canada shorton, Avalanche Canada

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Dangerous avalanche conditions will exist on slopes that receive more than 20 cm of new snow, which is most likely at higher elevations.

Summary

Confidence

Moderate - Forecast precipitation (either snow or rain) amounts are uncertain.

Weather Forecast

An offshore low pressure system is bringing cooler temperatures and flurries with highly variable amounts of new snow.

THURSDAY NIGHT: Scattered flurries with highly variable accumulations of new snow (5-15 cm), 40-50 km/h south wind, treeline temperatures around -1 C with freezing level around 1000 m.

FRIDAY: Scattered flurries continue with another 5-15 cm possible, resulting in 24 h accumulations between 5-30 cm, 40-60 km/h south wind, treeline temperatures around -2 C with freezing level around 1000 m.

SATURDAY: Flurries end by the morning then a mix of sun and cloud, 10 to 20 km/h southwest wind, treeline temperatures around -2 C, freezing level 800 m.

SUNDAY: 10-25 cm of snow, 40-50 km/h south wind, treeline temperatures around -4 C, freezing level 500 m.

Avalanche Summary

We haven't received any reports of avalanches in the past few days, but activity is expected to increase in the coming days as a series of storms impact the region.

Snowpack Summary

The current storm will transition from rain to snow on Thursday night as freezing levels drop to 1000 m. Snow accumulations are expected to be highly variable across the region on Friday, and will likely increase dramatically with elevation. Storm slabs will be reactive anywhere sufficient snow accumulates, especially on northerly aspects that will receive extra wind loading. Along ridgelines, cornices are large and always have the potential of failing or being triggered from the weight of a human.

Terrain and Travel

  • Dial back your terrain choices if you are seeing more than 20 cm of new snow.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.

Problems

Storm Slabs

An icon showing Storm Slabs

New snow will form reactive slabs in areas that receive more than 20 cm of new snow, which is most likely at higher elevations and in lee terrain (north and east facing).

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 19th, 2021 4:00PM