Avalanche Forecast

Issued: Apr 14th, 2023 4:00PM

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

TJ, Avalanche Canada

Jasper, Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Maligne, Marmot, Miette Lake, Pyramid.

Dig down and assess the snowpack before committing to terrain.

Summary

Confidence

High

Avalanche Summary

A size 2 skier remote or accidental triggered avalanche was observed on the regular approach to the north glacier on Mt. Athabasca on Thursday. No result from explosive control on Parker Slabs on Friday.

Don't forget to post avalanche observations to the MIN.

Snowpack Summary

Up to 20cm of snow sits on multiple crusts up to 2400m. Snow pit tests are showing results in the weak facet crystals below these crusts on south aspects. Above 2400m the surface snow is dry. The snowpack below 1800m is in a daily melt-freeze cycle. The mid-pack above this elevation consists of multiple layers of sun crusts or facets. Depth hoar and basal facets make up the base of the snowpack.

Weather Summary

Saturday

Cloudy with sunny periods and isolated flurries.

Precipitation: Trace.

Alpine temperature: High -4 °C.

Ridge wind southwest: 15-35 km/h.

Freezing level: 1800 metres.

Sunday

Flurries.

Accumulation: 8 cm.

Alpine temperature: Low -6 °C, High 0 °C.

Ridge wind southwest: 15-30 km/h.

Freezing level: 2300 metres.

Terrain and Travel Advice

Minimize exposure to sun-exposed slopes when the solar radiation is strong.
Remember that the snowpack will be significantly different at higher elevations than lower down.
Pay attention to the wind, once it starts to blow fresh sensitive wind slabs are likely to form.

Problems

Deep Persistent Slabs

The bottom of the snowpack is inherently weak with well-developed Facets and Depth Hoar.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3.5

Wind Slabs

South west winds will pick up through the weekend. Watch for newly developed wind slab in lee features.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Loose Wet

Stronger overnight freezes may keep this problem in check until mid to late afternoons. Watch out if the sun comes out. Wet loose avalanches can step-down to our basal facets in steep terrain resulting in large avalanches.

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

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Apr 15th, 2023 4:00PM