Avalanche Forecast

Issued: Mar 2nd, 2023 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 ahanna, Avalanche Canada

Email

Storm slabs will be most reactive where they continue to build with convective snowfall and where they have been touched by wind. Stick to conservative terrain and watch for signs of instability like shooting cracks, whumfing and recent avalanches.

Summary

Confidence

High

Avalanche Summary

So far, observations since the storm have been low elevation loose dry avalanches up to size 2, reported by our field team on Thursday.

A slew of MINs from the Mt Cain area over the weekend and Monday reported several rider triggered storm/wind slab avalanches up to size 2.

If you head into the backcountry please consider sharing your observations on the Mountain Information Network!

Snowpack Summary

New snow has likely been wind loaded into lee terrain features at wind-exposed elevations, while remaining soft in sheltered areas.

A thick, widespread crust formed in mid February sits 20-40 cm deep. Near Mt Cain, where the crust is glassy, a poor bond exists between it and the overlying snow. Elsewhere it seems to be bonding well. You can check the bond in your local area by performing a simple hand shear test on an isolated block.

The mid and lower snowpack is well consolidated, containing a series of well-bonded crusts.

Weather Summary

A cool, unstable airmass produces convective precipitation over the region. This means localized snowfall amounts that can vary widely.

Thursday night

1-10 cm of new snow. Moderate to strong westerly wind. Alpine low -7 ºC.

Friday

1-10 cm of new snow. Moderate southwest wind. Alpine high -5 ºC.

Saturday

Flurries. Moderate to strong southeast wind. Alpine high -4 ºC.

Sunday

A mix of sun and cloud. Southeast wind easing to light. Alpine high -2 ºC.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.
  • Seek out sheltered terrain where new snow hasn't been wind-affected.
  • Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
  • Keep in mind the crust offers an excellent bed surface for avalanches.
  • Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.

Problems

Storm Slabs

An icon showing Storm Slabs

Storm slabs will likely be reactive, especially where wind has formed deep deposits in leeward terrain features at upper elevations. At lower elevations, new snow gains cohesion and slab property as it settles.

There may remain potential for slabs to fail down to a recently buried crust, propagate widely and run surprisingly far.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 3rd, 2023 4:00PM