Avalanche Forecast

Issued: Feb 3rd, 2023 11:30AM

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

Avalanche Canada ahanna, Avalanche Canada

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New snow and extreme winds are creating very dangerous avalanche conditions.

Avoid all avalanche terrain.

Summary

Confidence

High

Avalanche Summary

We anticipate an ongoing widespread natural storm slab avalanche cycle during the storm Friday and Saturday.

Prior to this storm, recent avalanche observations have been limited to small wind slabs and cornice falls reported by our field team.

If you're heading out into the mountains, please consider sharing your observations on the Mountain Information Network!

Snowpack Summary

Friday's storm and continued snow squalls through Saturday will accumulate 30-60 cm of new snow. Strong to extreme winds will redistribute the new snow into deep slabs on leeward aspects.

The mid snowpack consists of 30-100 cm of recent January snow, sitting poorly bonded to a crusty underlying lower snowpack.

Weather Summary

Friday night

Heavy snowfall tapering. Southwest winds ramping up to 80 km/h, gusts up to 110 km/h. Temperatures plunging to near-20 C.

Saturday

Post-frontal snow squalls bring 25-30 cm to high terrain over the day. Sustained cold temperatures below -15 C and strong, gusting winds 80-110 km/h through the day, easing and warming overnight.

Sunday

Flurries easing in the morning, clearing to a mix of sun and cloud in the afternoon before clouding over in the evening ahead of the next storm. Westerly wind 40-60 km/h. Temperatures rising through the day, peaking near 0 C overnight.

Monday

5-15 cm of new snow overnight, clearing to a mix of sun and cloud. Moderate westerly wind, temperatures near 0 C in the morning dropping to -10 C through the day.

Tuesday

Clear skies, light to moderate northwest wind, temperature around -10 C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
  • Only the most simple non-avalanche terrain free of overhead hazard is appropriate at this time.

Problems

Storm Slabs

An icon showing Storm Slabs

New snow and gale winds are forming deep, reactive storm slabs concentrated in leeward terrain features.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1.5 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

A poorly bonded layer of faceted particles sits over a slippery crust in many areas. This layer was buried 30-100 cm deep prior to this weekend's storm so with the new snow load, it has potential to produce large, destructive avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Feb 4th, 2023 11:30AM