Avalanche Forecast

Issued: Nov 23rd, 2020 4:00PM

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

Jasper Snow Safety,

Fat hard slabs on facets and early season hazards are still a big concern out there, hope for lots of snow Tuesday night!

Summary

Weather Forecast

Tuesday, Flurries: 10 cm. Alpine temperature: High -7 °C. Ridge wind southwest: 20-35 km/h.

Wednesday, Scattered flurries: 5 cm. Alpine temperature: Low -14 °C, High -7 °C. Ridge wind west: 10-30 km/h.

Thursday, Cloudy with sunny periods and isolated flurries: Trace. Alpine temperature: Low -13 °C, High -10 °C. Ridge wind west: 20 km/h.

Snowpack Summary

The snowpack is highly variable depending on location. Height of snow at Parkers is ~100cm at treeline. The Nov.4 crust up to 2600m, and is up to 70cm deep. Test results on this crust have shown a mix of mod sudden/resistent planar results. Continued wind slab develop on N and E aspects ridgetop down into treeline. Basal layers continue to weaken

Avalanche Summary

Several natural wind slab and dry loose avalanches in the alpine on north aspects have been observed in the Icefields, Jasper and Bald hills region over the past few days. Natural avalanche activity has decreased, but there is still significant concern for human triggering.

Confidence

Forecast snowfall amounts are uncertain on Wednesday

Problems

Wind Slabs

An icon showing Wind Slabs

Recent winds and snow have formed wind slabs

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

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

Pockets of previous wind deposited snow overlies the Nov 4 rain crust. Test results are mixed on this layer but appears to be becoming more reactive with increased loads and continued faceting

  • Pockets of persistent slabs linger on alpine lee features.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Nov 24th, 2020 4:00PM