Avalanche Forecast

Issued: Mar 4th, 2023 4:00PM

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

Avalanche Canada rgoddard, Avalanche Canada

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Recent snow will need time to settle.

Watch out for building wind slabs.

Seek out low-angle sheltered areas for the best riding.

Summary

Confidence

Moderate

Avalanche Summary

Considering the amount of snow that our region has received over the last few days, it should be no surprise that there has been a widespread avalanche cycle. These have been in the form of storm and wind slabs and have reached up to size three. Keep your guard up and expect conditions to continue until the snow settles.

Snowpack Summary

Up to 100 cm have fallen over the last few days. Temperatures remain cool so much of this snow will take some time to settle. Southerly winds redistributed this new snow at higher elevations and in exposed areas creating reactive wind slabs. The new snow may have a poor bond to the underlying stiff wind slabs and faceted snow formed by recent cold temperatures.

A melt-freeze crust formed in mid-January is buried up to 170 to 190 cm deep in the alpine and at treeline. It is still a concern but it seems to be gaining strength.

Weather Summary

Saturday Night

Mostly cloudy with clear periods, no accumulation, winds southeast 30 km/h, treeline temperatures -8 °C, and freezing level down to 300 m.

Sunday

Mostly cloudy with sunny breaks, trace accumulation with potential convective flurries, winds southeast 20 km/h, treeline temperatures -8 °C, and freeing levels to 1000 m.

Monday

A mix of sun and cloud, trace accumulation, winds south southeast 15 km/h, treeline temperatures -10 to -5 °C.

Tuesday

A mix of sun and cloud, trace accumulation winds south 15 km/h, treeline temperatures -8 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for changing conditions today, storm slabs may become increasingly reactive.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Closely monitor how the new snow is bonding to the crust.
  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.
  • Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.

Problems

Storm Slabs

An icon showing Storm Slabs

Heavy snowfall over recent days is expected to form reactive storm slabs, especially if temperatures rise. At this time of year, if the sun makes an appearance will also promote slab formation.

Wind-loaded features should be avoided as they will deeper deposits of redistributed snow.

In many areas, this new snow may be bonding poorly to the underlying surface and storm slab reactivity may persist for longer than is typical.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A crust formed in mid-January can be found down 90 to 130 cm. In areas around the Coquihalla, facets can be found sitting on the crust. This layer is of greatest concern with large triggers, such as a cornice fall, or by first triggering a smaller avalanche that could step down to this interface.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Mar 5th, 2023 4:00PM