Avalanche Forecast

Issued: Nov 20th, 2020 4:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs, Persistent Slabs and Loose Dry.

Benjamin Firth,

Stay clear of wind loaded lee features and watch for hidden early season hazards. Don't get surprised, we have a long season ahead.

We appreciate your observations, please report on the MIN network if you have the opportunity

Summary

Weather Forecast

Tonight: Accumulation: 4 cm. Alpine temperature: Low -10 C. Ridge wind southwest: 15 km/h gusting to 50 km/h. Freezing level at valley bottom.

Saturday: Cloudy with sunny periods and isolated flurries. Precip: Trace. Alp temp: High -9 C. Ridge wind SW: 15-35 km/h.

Sunday: Precip: Nil. Alp temp: Low -14 C, High -9 C. wind SW: 10 km/h.

Snowpack Summary

Up to 40cm of new low density snow in the past 48 hours.The snowpack is ~100cm at treeline. The Nov. 4th rain crust up to 2600m depending on location, and is up to 55cm deep. Continued wind slab development on N and W aspects ridgetop down into treeline. Old wind slabs buried in exposed terrain that sit on the Nov 4th crust continue to be reactive

Avalanche Summary

Several natural wind slab avalanches in the alpine on north aspects have been observed in the Jasper and Bald hills region over the past 24 hours. No new avalanches observed in the Icefields region today. Observations were limited to treeline and below.

Confidence

Due to the quality of field observations on Friday

Problems

Wind Slabs

An icon showing Wind Slabs

Up to 40cm of new snow with moderate winds at ridge top has produced windslabs in the immediate lee at ridge tops and down into tree line.

  • Use caution in lee areas. Recent wind loading have created wind slabs.
  • Be careful with wind loaded pockets while approaching and climbing ice routes.

Aspects: North, North East, East, South East, North West.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

Pockets of previous wind deposited snow overlies the Nov 4 rain crust and continues to be reactive to skier traffic and large loads such as explosives.

  • Use caution in lee areas. Recent wind loading has created wind slabs.

Aspects: North, North East, East, South East, West, North West.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Loose Dry

An icon showing Loose Dry

Cool temps, winds and recent snowfall promoting loose dry avalanches in steep terrain.

  • Be cautious of sluffing in steep terrain.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Nov 21st, 2020 4:00PM